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Sample records for airborne vehicles uavs

  1. Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument

    SciTech Connect

    1998-12-01

    Using VLF frequencies, transmitted by the Navy`s network, for airborne remote sensing of the earth`s electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. The first VLF system was designed and developed by the USGS for installation and operation on a single engine, fixed wing aircraft used by the Branch of Geophysics for geophysical surveying. The system consisted of five channels. Two E-field channels with sensors consisting of a fixed vertical loaded dipole antenna with pre-amp mounted on top of the fuselage and a gyro stabilized horizontal loaded dipole antenna with pre-amp mounted on a tail boom. The three channel magnetic sensor consisted of three orthogonal coils mounted on the same gyro stabilized platform as the horizontal E-field antenna. The main features of the VLF receiver were: narrow band-width frequency selection using crystal filters, phase shifters for zeroing out system phase variances, phase-lock loops for generating real and quadrature gates, and synchronous detectors for generating real and quadrature outputs. In the mid 1990s the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas. Later the system was modified for installation on a Unmanned Airborne Vehicle (UAV). A series of three field trips were made to Easton, Maryland for testing and evaluating the system performance.

  2. The ARM unpiloted aerospace vehicle (UAV) program

    SciTech Connect

    Sowle, D.

    1995-09-01

    Unmanned aerospace vehicles (UAVs) are an important complement to the DOE`s Atmospheric Radiation Measurement (ARM) Program. ARM is primarily a ground-based program designed to extensively quantify the radiometric and meteorological properties of an atmospheric column. There is a need for airborne measurements of radiative profiles, especially flux at the tropopause, cloud properties, and upper troposphere water vapor. There is also a need for multi-day measurements at the tropopause; for example, in the tropics, at 20 km for over 24 hours. UAVs offer the greatest potential for long endurance at high altitudes and may be less expensive than piloted flights. 2 figs.

  3. Autonomous unmanned air vehicles (UAV) techniques

    NASA Astrophysics Data System (ADS)

    Hsu, Ming-Kai; Lee, Ting N.

    2007-04-01

    The UAVs (Unmanned Air Vehicles) have great potentials in different civilian applications, such as oil pipeline surveillance, precision farming, forest fire fighting (yearly), search and rescue, boarder patrol, etc. The related industries of UAVs can create billions of dollars for each year. However, the road block of adopting UAVs is that it is against FAA (Federal Aviation Administration) and ATC (Air Traffic Control) regulations. In this paper, we have reviewed the latest technologies and researches on UAV navigation and obstacle avoidance. We have purposed a system design of Jittering Mosaic Image Processing (JMIP) with stereo vision and optical flow to fulfill the functionalities of autonomous UAVs.

  4. Sandia Multispectral Airborne Lidar for UAV Deployment

    SciTech Connect

    Daniels, J.W.; Hargis,Jr. P.J.; Henson, T.D.; Jordan, J.D.; Lang, A.R.; Schmitt, R.L.

    1998-10-23

    Sandia National Laboratories has initiated the development of an airborne system for W laser remote sensing measurements. System applications include the detection of effluents associated with the proliferation of weapons of mass destruction and the detection of biological weapon aerosols. This paper discusses the status of the conceptual design development and plans for both the airborne payload (pointing and tracking, laser transmitter, and telescope receiver) and the Altus unmanned aerospace vehicle platform. Hardware design constraints necessary to maintain system weight, power, and volume limitations of the flight platform are identified.

  5. Atmospheric radiation measurement unmanned aerospace vehicle (ARM-UAV) program

    SciTech Connect

    Bolton, W.R.

    1996-11-01

    ARM-UAV is part of the multi-agency U.S. Global Change Research Program and is addressing the largest source of uncertainty in predicting climatic response: the interaction of clouds and the sun`s energy in the Earth`s atmosphere. An important aspect of the program is the use of unmanned aerospace vehicles (UAVs) as the primary airborne platform. The ARM-UAV Program has completed two major flight series: The first series conducted in April, 1994, using an existing UAV (the General Atomics Gnat 750) consisted of eight highly successful flights at the DOE climate site in Oklahoma. The second series conducted in September/October, 1995, using two piloted aircraft (Egrett and Twin Otter), featured simultaneous measurements above and below clouds and in clear sky. Additional flight series are planned to continue study of the cloudy and clear sky energy budget in the Spring and Fall of 1996 over the DOE climate site in Oklahoma. 3 refs., 4 figs., 1 tab.

  6. Earthbound Unmanned Autonomous Vehicles (UAVS) As Planetary Science Testbeds

    NASA Astrophysics Data System (ADS)

    Pieri, D. C.; Bland, G.; Diaz, J. A.; Fladeland, M. M.

    2014-12-01

    Recent advances in the technology of unmanned vehicles have greatly expanded the range of contemplated terrestrial operational environments for their use, including aerial, surface, and submarine. The advances have been most pronounced in the areas of autonomy, miniaturization, durability, standardization, and ease of operation, most notably (especially in the popular press) for airborne vehicles. Of course, for a wide range of planetary venues, autonomy at high cost of both money and risk, has always been a requirement. Most recently, missions to Mars have also featured an unprecedented degree of mobility. Combining the traditional planetary surface deployment operational and science imperatives with emerging, very accessible, and relatively economical small UAV platforms on Earth can provide flexible, rugged, self-directed, test-bed platforms for landed instruments and strategies that will ultimately be directed elsewhere, and, in the process, provide valuable earth science data. While the most direct transfer of technology from terrestrial to planetary venues is perhaps for bodies with atmospheres (and oceans), with appropriate technology and strategy accommodations, single and networked UAVs can be designed to operate on even airless bodies, under a variety of gravities. In this presentation, we present and use results and lessons learned from our recent earth-bound UAV volcano deployments, as well as our future plans for such, to conceptualize a range of planetary and small-body missions. We gratefully acknowledge the assistance of students and colleagues at our home institutions, and the government of Costa Rica, without which our UAV deployments would not have been possible. This work was carried out, in part, at the Jet Propulsion Laboratory of the California Institute of Technology under contract to NASA.

  7. Briefing to University of Porto on NASA Airborne Science Program and Ames UAVs

    NASA Technical Reports Server (NTRS)

    Fladeland, Matthew

    2015-01-01

    NASA Ames is exploring a partnership with the University of Portugal to jointly develop and test new autonomous vehicle technologies. As part of the discussions I will be briefing the University of Portugal faculty on the NASA Airborne Science Program (ASP) and associated activities at NASA Ames Research Center. The presentation will communicate the requirements that drive the program, the assets available to NASA researchers, and discuss research projects that have used unmanned aircraft systems including MIZOPEX, Surprise Valley, and Florida Keys Coral Reef assessment. Other topics will include the SIERRA and Dragon Eye UAV projects operated at Ames.

  8. Challenges in collecting hyperspectral imagery of coastal waters using Unmanned Aerial Vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    English, D. C.; Herwitz, S.; Hu, C.; Carlson, P. R., Jr.; Muller-Karger, F. E.; Yates, K. K.; Ramsewak, D.

    2013-12-01

    Airborne multi-band remote sensing is an important tool for many aquatic applications; and the increased spectral information from hyperspectral sensors may increase the utility of coastal surveys. Recent technological advances allow Unmanned Aerial Vehicles (UAVs) to be used as alternatives or complements to manned aircraft or in situ observing platforms, and promise significant advantages for field studies. These include the ability to conduct programmed flight plans, prolonged and coordinated surveys, and agile flight operations under difficult conditions such as measurements made at low altitudes. Hyperspectral imagery collected from UAVs should allow the increased differentiation of water column or shallow benthic communities at relatively small spatial scales. However, the analysis of hyperspectral imagery from airborne platforms over shallow coastal waters differs from that used for terrestrial or oligotrophic ocean color imagery, and the operational constraints and considerations for the collection of such imagery from autonomous platforms also differ from terrestrial surveys using manned aircraft. Multispectral and hyperspectral imagery of shallow seagrass and coral environments in the Florida Keys were collected with various sensor systems mounted on manned and unmanned aircrafts in May 2012, October 2012, and May 2013. The imaging systems deployed on UAVs included NovaSol's Selectable Hyperspectral Airborne Remote-sensing Kit (SHARK), a Tetracam multispectral imaging system, and the Sunflower hyperspectal imager from Galileo Group, Inc. The UAVs carrying these systems were Xtreme Aerial Concepts' Vision-II Rotorcraft UAV, MLB Company's Bat-4 UAV, and NASA's SIERRA UAV, respectively. Additionally, the Galileo Group's manned aircraft also surveyed the areas with their AISA Eagle hyperspectral imaging system. For both manned and autonomous flights, cloud cover and sun glint (solar and viewing angles) were dominant constraints on retrieval of quantitatively

  9. A new stratospheric sounding platform based on unmanned aerial vehicle (UAV) droppable from meteorological balloon

    NASA Astrophysics Data System (ADS)

    Efremov, Denis; Khaykin, Sergey; Lykov, Alexey; Berezhko, Yaroslav; Lunin, Aleksey

    High-resolution measurements of climate-relevant trace gases and aerosols in the upper troposphere and stratosphere (UTS) have been and remain technically challenging. The high cost of measurements onboard airborne platforms or heavy stratospheric balloons results in a lack of accurate information on vertical distribution of atmospheric constituents. Whereas light-weight instruments carried by meteorological balloons are becoming progressively available, their usage is constrained by the cost of the equipment or the recovery operations. The evolving need in cost-efficient observations for UTS process studies has led to development of small airborne platforms - unmanned aerial vehicles (UAV), capable of carrying small sensors for in-situ measurements. We present a new UAV-based stratospheric sounding platform capable of carrying scientific payload of up to 2 kg. The airborne platform comprises of a latex meteorological balloon and detachable flying wing type UAV with internal measurement controller. The UAV is launched on a balloon to stratospheric altitudes up to 20 km, where it can be automatically released by autopilot or by a remote command sent from the ground control. Having been released from the balloon the UAV glides down and returns to the launch position. Autopilot using 3-axis gyro, accelerometer, barometer, compas and GPS navigation provides flight stabilization and optimal way back trajectory. Backup manual control is provided for emergencies. During the flight the onboard measurement controller stores the data into internal memory and transmits current flight parameters to the ground station via telemetry. Precise operation of the flight control systems ensures safe landing at the launch point. A series of field tests of the detachable stratospheric UAV has been conducted. The scientific payload included the following instruments involved in different flights: a) stratospheric Lyman-alpha hygrometer (FLASH); b) backscatter sonde; c) electrochemical

  10. Measuring orthometric water heights from lightweight Unmanned Aerial Vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    Bandini, Filippo; Olesen, Daniel; Jakobsen, Jakob; Reyna-Gutierrez, Jose Antonio; Bauer-Gottwein, Peter

    2016-04-01

    A better quantitative understanding of hydrologic processes requires better observations of hydrological variables, such as surface water area, water surface level, its slope and its temporal change. However, ground-based measurements of water heights are restricted to the in-situ measuring stations. Hence, the objective of remote sensing hydrology is to retrieve these hydraulic variables from spaceborne and airborne platforms. The forthcoming Surface Water and Ocean Topography (SWOT) satellite mission will be able to acquire water heights with an expected accuracy of 10 centimeters for rivers that are at least 100 m wide. Nevertheless, spaceborne missions will always face the limitations of: i) a low spatial resolution which makes it difficult to separate water from interfering surrounding areas and a tracking of the terrestrial water bodies not able to detect water heights in small rivers or lakes; ii) a limited temporal resolution which limits the ability to determine rapid temporal changes, especially during extremes. Unmanned Aerial Vehicles (UAVs) are one technology able to fill the gap between spaceborne and ground-based observations, ensuring 1) high spatial resolution; 2) tracking of the water bodies better than any satellite technology; 3) timing of the sampling which only depends on the operator 4) flexibility of the payload. Hence, this study focused on categorizing and testing sensors capable of measuring the range between the UAV and the water surface. The orthometric height of the water surface is then retrieved by subtracting the height above water measured by the sensors from the altitude above sea level retrieved by the onboard GPS. The following sensors were tested: a) a radar, b) a sonar c) a laser digital-camera based prototype developed at Technical University of Denmark. The tested sensors comply with the weight constraint of small UAVs (around 1.5 kg). The sensors were evaluated in terms of accuracy, maximum ranging distance and beam

  11. UAVs in climate research: The ARM Unmanned Aerospace Vehicle Program

    SciTech Connect

    Bolton, W.R.

    1994-05-01

    In the last year, a Department of Energy/Strategic Environmental Research and Development Program project known as ``ARM-UAV`` has made important progress in developing and demonstrating the utility of unmanned aerospace vehicles as platforms for scientific measurements. Recent accomplishments include a series of flights using an atmospheric research payload carried by a General Atomics Gnat UAV at Edwards AFB, California, and over ground instruments located in north-central Oklahoma. The reminder of this discussion will provide background on the program and describe the recent flights.

  12. Unmanned aerial vehicles (UAV) in atmospheric research and satellite validation

    NASA Astrophysics Data System (ADS)

    Sitnikov, Nikolay; Borisov, Yuriy; Akmulin, Dimitry; Chekulaev, Igor; Efremov, Denis; Sitnikova, Vera; Ulanovsky, Alexey; Popovicheva, Olga

    The perspectives of the development of methods and facilities based on UAV for atmospheric investigations are considered. Some aspects of these methods applications are discussed. Developments of the experimental samples of UAV onboard equipment for measurements of atmospheric parameters carried out in Central Aerological Observatory are presented. Hardware system for the UAV is developed. The results of measurements of the spatial distributions of the thermodynamic parameters and the concentrations of some gas species onboard of remotely piloted and unmanned aerial vehicles obtained in field tests are presented. The development can be used for satellite data validation, as well as operative environmental monitoring of contaminated areas in particular, chemical plants, natural and industrial disasters territories, areas and facilities for space purposes , etc.

  13. Autonomous Navigation of Small Uavs Based on Vehicle Dynamic Model

    NASA Astrophysics Data System (ADS)

    Khaghani, M.; Skaloud, J.

    2016-03-01

    This paper presents a novel approach to autonomous navigation for small UAVs, in which the vehicle dynamic model (VDM) serves as the main process model within the navigation filter. The proposed method significantly increases the accuracy and reliability of autonomous navigation, especially for small UAVs with low-cost IMUs on-board. This is achieved with no extra sensor added to the conventional INS/GNSS setup. This improvement is of special interest in case of GNSS outages, where inertial coasting drifts very quickly. In the proposed architecture, the solution to VDM equations provides the estimate of position, velocity, and attitude, which is updated within the navigation filter based on available observations, such as IMU data or GNSS measurements. The VDM is also fed with the control input to the UAV, which is available within the control/autopilot system. The filter is capable of estimating wind velocity and dynamic model parameters, in addition to navigation states and IMU sensor errors. Monte Carlo simulations reveal major improvements in navigation accuracy compared to conventional INS/GNSS navigation system during the autonomous phase, when satellite signals are not available due to physical obstruction or electromagnetic interference for example. In case of GNSS outages of a few minutes, position and attitude accuracy experiences improvements of orders of magnitude compared to inertial coasting. It means that during such scenario, the position-velocity-attitude (PVA) determination is sufficiently accurate to navigate the UAV to a home position without any signal that depends on vehicle environment.

  14. NASA UAV Airborne Science Capabilities in Support of Water Resource Management

    NASA Technical Reports Server (NTRS)

    Fladeland, Matthew

    2015-01-01

    This workshop presentation focuses on potential uses of unmanned aircraft observations in support of water resource management and agriculture. The presentation will provide an overview of NASA Airborne Science capabilities with an emphasis on past UAV missions to provide context on accomplishments as well as technical challenges. I will also focus on recent NASA Ames efforts to assist in irrigation management and invasive species management using airborne and satellite datasets.

  15. Unmanned air vehicle (UAV) ultra-persitence research

    SciTech Connect

    Dron, S. B.

    2012-03-01

    Sandia National Laboratories and Northrop Grumman Corporation Integrated Systems, Unmanned Systems (NGIS UMS) collaborated to further ultra-persistence technologies for unmanned air vehicles (UAVs). The greatest shortfalls in UAV capabilities have been repeatedly identified as (1) insufficient flight persistence or 'hang time,' (2) marginal electrical power for running higher power avionics and payload systems, and (3) inadequate communications bandwidth and reach. NGIS UMS requested support from Sandia to develop an ultra-persistent propulsion and power system (UP3S) for potential incorporation into next generation UAV systems. The team members tried to determine which energy storage and power generation concepts could most effectively push UAV propulsion and electrical power capabilities to increase UAV sortie duration from days to months while increasing available electrical power at least two-fold. Primary research and development areas that were pursued included these goals: perform general system engineering and integration analyses; develop initial thermal and electrical power estimates; provide mass, volume, dimensional, and balance estimates; conduct preliminary safety assessments; assess logistics support requirements; perform, preliminary assessments of any security and safeguards; evaluate options for removal, replacement, and disposition of materials; generally advance the potential of the UP3S concept. The effort contrasted and compared eight heat sources technologies, three power conversion, two dual cycle propulsion system configurations, and a single electrical power generation scheme. Overall performance, specific power parameters, technical complexities, security, safety, and other operational features were successfully investigated. Large and medium sized UAV systems were envisioned and operational flight profiles were developed for each concept. Heat source creation and support challenges for domestic and expeditionary operations were

  16. Unmanned Aerial Vehicles (UAVs): a new tool in counterterrorism operations?

    NASA Astrophysics Data System (ADS)

    Dörtbudak, Mehmet F.

    2015-05-01

    Terrorism is not a new phenomenon to the world, yet it remains difficult to define and counter. Countering terrorism requires several measures that must be taken simultaneously; however, counterterrorism strategies of many countries mostly depend on military measures. In the aftermath of the 2001 terrorist attack on the Twin Towers of the World Trade Center, the United States (U.S.) has started and led the campaign of Global War on Terrorism. They have invaded Afghanistan and Iraq and have encountered insurgencies run by terrorist organizations, such as al-Qaeda and its affiliates. The U.S. made the utilization of Air and Space Power very intensively during these operations. In order to implement operations; Intelligence, Surveillance, and Reconnaissance (ISR) assets were used to collect the necessary information. Before the successful insertion of a small number of U.S. Special Operation Force (SOF) teams into Afghanistan, the U.S. Air Force attacked al-Qaeda and Taliban's targets such as infrastructure, airfields, ground forces, command-control facilities etc. As soon as the U.S. troops got on the ground and started to marshal to Kabul, the Air Force supported them by attacking jointly determined targets. The Air Force continued to carry out the missions and played a significant role to achieve the objective of operation during all the time. This is not the only example of utilization of Air and Space Power in counterterrorism and counterinsurgency operations. All around the world, many countries have also made the utilization of Air Power in different missions ranging from ISR to attacking. Thinking that terrorism has a psychological dimension and losing a pilot during operations may result in decreasing the population support to operations, Unmanned Aerial Vehicles (UAVs) started to be used by practitioners and took priority over other assets. Although UAVs have been on the theatre for a long time used for ISR mission in conventional conflicts, with the advent

  17. Spectrum correction algorithm for detectors in airborne radioactivity monitoring equipment NH-UAV based on a ratio processing method

    NASA Astrophysics Data System (ADS)

    Cao, Ye; Tang, Xiao-Bin; Wang, Peng; Meng, Jia; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2015-10-01

    The unmanned aerial vehicle (UAV) radiation monitoring method plays an important role in nuclear accidents emergency. In this research, a spectrum correction algorithm about the UAV airborne radioactivity monitoring equipment NH-UAV was studied to measure the radioactive nuclides within a small area in real time and in a fixed place. The simulation spectra of the high-purity germanium (HPGe) detector and the lanthanum bromide (LaBr3) detector in the equipment were obtained using the Monte Carlo technique. Spectrum correction coefficients were calculated after performing ratio processing techniques about the net peak areas between the double detectors on the detection spectrum of the LaBr3 detector according to the accuracy of the detection spectrum of the HPGe detector. The relationship between the spectrum correction coefficient and the size of the source term was also investigated. A good linear relation exists between the spectrum correction coefficient and the corresponding energy (R2=0.9765). The maximum relative deviation from the real condition reduced from 1.65 to 0.035. The spectrum correction method was verified as feasible.

  18. Wetland Assessment Using Unmanned Aerial Vehicle (uav) Photogrammetry

    NASA Astrophysics Data System (ADS)

    Boon, M. A.; Greenfield, R.; Tesfamichael, S.

    2016-06-01

    The use of Unmanned Arial Vehicle (UAV) photogrammetry is a valuable tool to enhance our understanding of wetlands. Accurate planning derived from this technological advancement allows for more effective management and conservation of wetland areas. This paper presents results of a study that aimed at investigating the use of UAV photogrammetry as a tool to enhance the assessment of wetland ecosystems. The UAV images were collected during a single flight within 2½ hours over a 100 ha area at the Kameelzynkraal farm, Gauteng Province, South Africa. An AKS Y-6 MKII multi-rotor UAV and a digital camera on a motion compensated gimbal mount were utilised for the survey. Twenty ground control points (GCPs) were surveyed using a Trimble GPS to achieve geometrical precision and georeferencing accuracy. Structure-from-Motion (SfM) computer vision techniques were used to derive ultra-high resolution point clouds, orthophotos and 3D models from the multi-view photos. The geometric accuracy of the data based on the 20 GCP's were 0.018 m for the overall, 0.0025 m for the vertical root mean squared error (RMSE) and an over all root mean square reprojection error of 0.18 pixel. The UAV products were then edited and subsequently analysed, interpreted and key attributes extracted using a selection of tools/ software applications to enhance the wetland assessment. The results exceeded our expectations and provided a valuable and accurate enhancement to the wetland delineation, classification and health assessment which even with detailed field studies would have been difficult to achieve.

  19. Photovoltaic electric power applied to Unmanned Aerial Vehicles (UAV)

    SciTech Connect

    Geis, J.; Arnold, J.H.

    1994-09-01

    Photovoltaic electric-powered flight is receiving a great deal of attention in the context of the United States` Unmanned Aerial Vehicle (UAV) program. This paper addresses some of the enabling technical areas and their potential solutions. Of particular interest are the long-duration, high-altitude class of UAV`s whose mission it is to achieve altitudes between 60,000 and 100,000 feet, and to remain at those altitudes for prolonged periods performing various mapping and surveillance activities. Addressed herein are studies which reveal the need for extremely light-weight and efficient solar cells, high-efficiency electric motor-driven propeller modules, and power management and distribution control elements. Since the potential payloads vary dramatically in their power consumption and duty cycles, a typical load profile has been selected to provide commonality for the propulsion power comparisons. Since missions vary widely with respect to ground coverage requirements, from repeated orbiting over a localized target to long-distance routes over irregular terrain, the authors have also averaged the power requirements for on-board guidance and control power, as well as ground control and communication link utilization. In the context of the national technology reinvestment program, wherever possible they modeled components and materials which have been qualified for space and defense applications, yet are compatible with civilian UAV activities. These include, but are not limited to, solar cell developments, electric storage technology for diurnal operation, local and ground communications, power management and distribution, and control servo design. And finally, the results of tests conducted by Wright Laboratory on ultralight, highly efficient MOCVD GaAs solar cells purchased from EPI Materials Ltd. (EML) of the UK are presented. These cells were also used for modeling the flight characteristics of UAV aircraft.

  20. Real-time people and vehicle detection from UAV imagery

    NASA Astrophysics Data System (ADS)

    Gaszczak, Anna; Breckon, Toby P.; Han, Jiwan

    2011-01-01

    A generic and robust approach for the real-time detection of people and vehicles from an Unmanned Aerial Vehicle (UAV) is an important goal within the framework of fully autonomous UAV deployment for aerial reconnaissance and surveillance. Here we present an approach for the automatic detection of vehicles based on using multiple trained cascaded Haar classifiers with secondary confirmation in thermal imagery. Additionally we present a related approach for people detection in thermal imagery based on a similar cascaded classification technique combining additional multivariate Gaussian shape matching. The results presented show the successful detection of vehicle and people under varying conditions in both isolated rural and cluttered urban environments with minimal false positive detection. Performance of the detector is optimized to reduce the overall false positive rate by aiming at the detection of each object of interest (vehicle/person) at least once in the environment (i.e. per search patter flight path) rather than every object in each image frame. Currently the detection rate for people is ~70% and cars ~80% although the overall episodic object detection rate for each flight pattern exceeds 90%.

  1. Analysis of Unmanned Aerial Vehicle (UAV) hyperspectral remote sensing monitoring key technology in coastal wetland

    NASA Astrophysics Data System (ADS)

    Ma, Yi; Zhang, Jie; Zhang, Jingyu

    2016-01-01

    The coastal wetland, a transitional zone between terrestrial ecosystems and marine ecosystems, is the type of great value to ecosystem services. For the recent 3 decades, area of the coastal wetland is decreasing and the ecological function is gradually degraded with the rapid development of economy, which restricts the sustainable development of economy and society in the coastal areas of China in turn. It is a major demand of the national reality to carry out the monitoring of coastal wetlands, to master the distribution and dynamic change. UAV, namely unmanned aerial vehicle, is a new platform for remote sensing. Compared with the traditional satellite and manned aerial remote sensing, it has the advantage of flexible implementation, no cloud cover, strong initiative and low cost. Image-spectrum merging is one character of high spectral remote sensing. At the same time of imaging, the spectral curve of each pixel is obtained, which is suitable for quantitative remote sensing, fine classification and target detection. Aimed at the frontier and hotspot of remote sensing monitoring technology, and faced the demand of the coastal wetland monitoring, this paper used UAV and the new remote sensor of high spectral imaging instrument to carry out the analysis of the key technologies of monitoring coastal wetlands by UAV on the basis of the current situation in overseas and domestic and the analysis of developing trend. According to the characteristic of airborne hyperspectral data on UAV, that is "three high and one many", the key technology research that should develop are promoted as follows: 1) the atmosphere correction of the UAV hyperspectral in coastal wetlands under the circumstance of complex underlying surface and variable geometry, 2) the best observation scale and scale transformation method of the UAV platform while monitoring the coastal wetland features, 3) the classification and detection method of typical features with high precision from multi scale

  2. Complementing airborne laser bathymetry with UAV-based lidar for capturing alluvial landscapes

    NASA Astrophysics Data System (ADS)

    Mandlburger, Gottfried; Pfennigbauer, Martin; Riegl, Ursula; Haring, Alexander; Wieser, Martin; Glira, Philipp; Winiwarter, Lukas

    2015-10-01

    In this paper we report on a flight experiment employing airborne laser bathymetry (ALB) and unmanned aerial vehicle (UAV) based laser scanning (ULS) for capturing very high resolution topography of shallow water areas and the surrounding littoral zone at the pre-alpine Pielach River in Austria. The aim of the research is to assess how information gained from non-bathymetric, ultra-high resolution ULS can support the ALB data. We focus first on the characterization of the water surface of a lowland river and provide validation results using the data of a topographic airborne laser scanning (ALS) sensor and a low flying ULS system. By repeat ULS survey of a the meandering river reach we are able to quantify short-term water level changes due to surface waves in high resolution. Based on a hydrodynamic-numerical (HN) model we assess the accuracy of the water surface derived from a water penetrating ALB sensor. In the second part of the paper we investigate the ability of ALB, ALS, and ULS to describe the complex topography and vegetation structure of the alluvial area. This is carried out by comparing the Digital Terrain Models (DTM) derived from different sensor configurations. Finally we demonstrate the potential of ULS for estimating single tree positions and stem diameters for detailed floodplain roughness characterization in HN simulations. The key findings are: (i) NIR scan data from ALS or ULS provide more precise water level height estimates (no bias, 1σ: 2 cm) compared to ALB (bias: 3 cm, 1σ: 4 cm), (ii) within the studied reach short-term water level dynamics irrelevant for ALB data acquisition considering a 60 cm footprint diameter, and (iii) stem diameters can be estimated based on ULS point clouds but not from ALS and ALB.

  3. Unmanned aerial vehicles (UAVs) in pest management: Progress in the development of a UAV-deployed mating disruption system for Wisconsin cranberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) represent a powerful new tool for agriculture. Currently, UAVs are used almost exclusively as crop reconnaissance devices (“eyes in the sky”), not as pest control delivery systems. Research in Wisconsin cranberries is taking UAVs in a new direction. The Steffan and Lu...

  4. Unmanned aerial vehicles (UAVs) in pest management: Progress in the development of a UAV-deployed mating disruption system for Wisconsin cranberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) hold significant promise for agriculture. Currently, UAVs are being employed for various reconnaissance purposes (“eyes in the sky”), but not as pest control delivery systems. Research in Wisconsin cranberries is taking UAVs in a new direction. The Steffan and Luck La...

  5. Photovoltaic electric power applied to Unmanned Aerial Vehicles (UAV)

    NASA Technical Reports Server (NTRS)

    Geis, Jack; Arnold, Jack H.

    1994-01-01

    Photovoltaic electric-powered flight is receiving a great deal of attention in the context of the United States' Unmanned Aerial Vehicle (UAV) program. This paper addresses some of the enabling technical areas and their potential solutions. Of particular interest are the long-duration, high-altitude class of UAV's whose mission it is to achieve altitudes between 60,000 and 100,000 feet, and to remain at those altitudes for prolonged periods performing various mapping and surveillance activities. Addressed herein are studies which reveal the need for extremely light-weight and efficient solar cells, high-efficiency electric motor-driven propeller modules, and power management and distribution control elements. Since the potential payloads vary dramatically in their power consumption and duty cycles, a typical load profile has been selected to provide commonality for the propulsion power comparisons. Since missions vary widely with respect to ground coverage requirements, from repeated orbiting over a localized target to long-distance routes over irregular terrain, we have also averaged the power requirements for on-board guidance and control power, as well as ground control and communication link utilization. In the context of the national technology reinvestment program, wherever possible we modeled components and materials which have been qualified for space and defense applications, yet are compatible with civilian UAV activities. These include, but are not limited to, solar cell developments, electric storage technology for diurnal operation, local and ground communications, power management and distribution, and control servo design. And finally, the results of tests conducted by Wright Laboratory on ultralight, highly efficient MOCVD GaAs solar cells purchased from EPI Materials Ltd. (EML) of the UK are presented. These cells were also used for modeling the flight characteristics of UAV aircraft.

  6. Mapping Geomagnetic Field Variations in the Cretaceous Quiet Zone with Unmanned Airborne Vehicles

    NASA Astrophysics Data System (ADS)

    Gee, J. S.; Cande, S. C.; Kent, D. V.

    2007-12-01

    About one quarter of the present seafloor was generated during the constant normal polarity interval from 121 to 83 Ma (Cretaceous Quiet Zone or KQZ), and the lack of temporal markers limits tectonic reconstructions in these areas. Although magnetostratigraphic studies provide strong evidence that the KQZ formed during predominantly normal polarity, there are nonetheless relatively large amplitude variations in many sea surface magnetic anomaly profiles crossing KQZ crust. To evaluate the relative importance of geomagnetic and crustal variables (thickness, geochemistry) in generating these anomalies, we collected multibeam bathymetry and magnetic data on 19 profiles crossing anomaly 34 and extending 500 km into the KQZ in the southwest Pacific. The relatively fast spreading (60 km/m.y. half rate), minimal sediment cover and high paleolatitude of formation make this area ideal for evaluating the magnetic anomaly pattern. An additional 10,000 km of magnetic anomaly data were acquired using an autonomous unmanned airborne vehicle (UAV). Although land-launched UAVs have been used in a variety of research applications, the nine successful flights during our cruise represent the first deployment from a UNOLS research vessel. The UAV (operated by Fugro Airborne) was launched from a pneumatic catapult and captured by a wingtip clip that attaches to a rope suspended from a retractable boom on the fantail. The Cs-vapor magnetometer data from the UAV compare favorably with results from the surface-towed magnetometer, with minor differences related primarily to the higher elevation (120m above sea level) of the UAV. The resulting magnetic coverage indicates that, as with younger seafloor, quasi-linear short wavelength anomalies are present within the KQZ. These anomalies can vary on spatial scales smaller than the multibeam swath width, highlighting the utility of obtaining additional coverage with the UAVs.

  7. Evaluation of unmanned airborne vehicles and mobile robotic telesurgery in an extreme environment.

    PubMed

    Harnett, Brett M; Doarn, Charles R; Rosen, Jacob; Hannaford, Blake; Broderick, Timothy J

    2008-08-01

    As unmanned extraction vehicles become a reality in the military theater, opportunities to augment medical operations with telesurgical robotics become more plausible. This project demonstrated an experimental surgical robot using an unmanned airborne vehicle (UAV) as a network topology. Because battlefield operations are dynamic and geographically challenging, the installation of wireless networks is not a feasible option at this point. However, to utilize telesurgical robotics to assist in the urgent medical care of wounded soldiers, a robust, high bandwidth, low latency network is requisite. For the first time, a mobile surgical robotic system was deployed to an austere environment and surgeons were able to remotely operate the systems wirelessly using a UAV. Two University of Cincinnati surgeons were able to remotely drive the University of Washington's RAVEN robot's end effectors. The network topology demonstrated a highly portable, quickly deployable, bandwidth-sufficient and low latency wireless network required for battlefield use.

  8. Fault detection and multiclassifier fusion for unmanned aerial vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    Yan, Weizhong

    2001-03-01

    UAVs demand more accurate fault accommodation for their mission manager and vehicle control system in order to achieve a reliability level that is comparable to that of a pilot aircraft. This paper attempts to apply multi-classifier fusion techniques to achieve the necessary performance of the fault detection function for the Lockheed Martin Skunk Works (LMSW) UAV Mission Manager. Three different classifiers that meet the design requirements of the fault detection of the UAAV are employed. The binary decision outputs from the classifiers are then aggregated using three different classifier fusion schemes, namely, majority vote, weighted majority vote, and Naieve Bayes combination. All of the three schemes are simple and need no retraining. The three fusion schemes (except the majority vote that gives an average performance of the three classifiers) show the classification performance that is better than or equal to that of the best individual. The unavoidable correlation between the classifiers with binary outputs is observed in this study. We conclude that it is the correlation between the classifiers that limits the fusion schemes to achieve an even better performance.

  9. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV.

  10. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    PubMed

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. PMID:26773821

  11. Cost and effectiveness analysis on unmanned aerial vehicle (UAV) use at border security

    NASA Astrophysics Data System (ADS)

    Yilmaz, Bahadır.

    2013-06-01

    Drones and Remotely Piloted Vehicles are types of Unmanned Aerial Vehicles. UAVs began to be used with the war of Vietnam, they had a great interest when Israel used them in Bekaa Valley Operations of 1982. UAVs have been used by different countries with different aims with the help of emerging technology and investments. In this article, in the context of areas of UAV usage in national security, benefits and disadvantages of UAVs are put forward. Particularly, it has been evaluated on the basis of cost-effectiveness by focusing the use of UAV in the border security. UAVs have been studied by taking cost analysis, procurement and operational costs into consideration. Analysis of effectiveness has been done with illegal passages of people and drugs from flight times of UAVs. Although the procurement cost of the medium-level UAVs is low, its operational costs are high. For this reason, the idea of less costly alternative systems have been revealed for the border security. As the costs are reduced to acceptable level involving national security and border security in future with high-technology products in their structure, it will continue to be used in an increasing proportion.

  12. Selectable Hyperspectral Airborne Remote-sensing Kit (SHARK) on the Vision II turbine rotorcraft UAV over the Florida Keys

    NASA Astrophysics Data System (ADS)

    Holasek, R. E.; Nakanishi, K.; Swartz, B.; Zacaroli, R.; Hill, B.; Naungayan, J.; Herwitz, S.; Kavros, P.; English, D. C.

    2013-12-01

    As part of the NASA ROSES program, the NovaSol Selectable Hyperspectral Airborne Remote-sensing Kit (SHARK) was flown as the payload on the unmanned Vision II helicopter. The goal of the May 2013 data collection was to obtain high resolution visible and near-infrared (visNIR) hyperspectral data of seagrasses and coral reefs in the Florida Keys. The specifications of the SHARK hyperspectral system and the Vision II turbine rotorcraft will be described along with the process of integrating the payload to the vehicle platform. The minimal size, weight, and power (SWaP) specifications of the SHARK system is an ideal match to the Vision II helicopter and its flight parameters. One advantage of the helicopter over fixed wing platforms is its inherent ability to take off and land in a limited area and without a runway, enabling the UAV to be located in close proximity to the experiment areas and the science team. Decisions regarding integration times, waypoint selection, mission duration, and mission frequency are able to be based upon the local environmental conditions and can be modified just prior to take off. The operational procedures and coordination between the UAV pilot, payload operator, and scientist will be described. The SHARK system includes an inertial navigation system and digital elevation model (DEM) which allows image coordinates to be calculated onboard the aircraft in real-time. Examples of the geo-registered images from the data collection will be shown. SHARK mounted below VTUAV. SHARK deployed on VTUAV over water.

  13. Multi-Unmanned Aerial Vehicle (UAV) Cooperative Fault Detection Employing Differential Global Positioning (DGPS), Inertial and Vision Sensors.

    PubMed

    Heredia, Guillermo; Caballero, Fernando; Maza, Iván; Merino, Luis; Viguria, Antidio; Ollero, Aníbal

    2009-01-01

    This paper presents a method to increase the reliability of Unmanned Aerial Vehicle (UAV) sensor Fault Detection and Identification (FDI) in a multi-UAV context. Differential Global Positioning System (DGPS) and inertial sensors are used for sensor FDI in each UAV. The method uses additional position estimations that augment individual UAV FDI system. These additional estimations are obtained using images from the same planar scene taken from two different UAVs. Since accuracy and noise level of the estimation depends on several factors, dynamic replanning of the multi-UAV team can be used to obtain a better estimation in case of faults caused by slow growing errors of absolute position estimation that cannot be detected by using local FDI in the UAVs. Experimental results with data from two real UAVs are also presented.

  14. Multi-Unmanned Aerial Vehicle (UAV) Cooperative Fault Detection Employing Differential Global Positioning (DGPS), Inertial and Vision Sensors

    PubMed Central

    Heredia, Guillermo; Caballero, Fernando; Maza, Iván; Merino, Luis; Viguria, Antidio; Ollero, Aníbal

    2009-01-01

    This paper presents a method to increase the reliability of Unmanned Aerial Vehicle (UAV) sensor Fault Detection and Identification (FDI) in a multi-UAV context. Differential Global Positioning System (DGPS) and inertial sensors are used for sensor FDI in each UAV. The method uses additional position estimations that augment individual UAV FDI system. These additional estimations are obtained using images from the same planar scene taken from two different UAVs. Since accuracy and noise level of the estimation depends on several factors, dynamic replanning of the multi-UAV team can be used to obtain a better estimation in case of faults caused by slow growing errors of absolute position estimation that cannot be detected by using local FDI in the UAVs. Experimental results with data from two real UAVs are also presented. PMID:22400008

  15. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images.

    PubMed

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-08-19

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles' in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians.

  16. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images.

    PubMed

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-01-01

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles' in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians. PMID:27548179

  17. Airborne Dust in Space Vehicles and Habitats

    NASA Technical Reports Server (NTRS)

    James, John

    2006-01-01

    Airborne dust, suspended inside a space vehicle or in future celestial habitats, can present a serious threat to crew health if it is not controlled. During the Apollo missions to the moon, lunar dust brought inside the capsule caused eye irritation and breathing difficulty to the crew when they launched from the moon and re-acquired "microgravity." During Shuttle flights reactive and toxic dusts such as lithium hydroxide have created a risk to crew health, and fine particles from combustion events can be especially worrisome. Under nominal spaceflight conditions, airborne dusts and particles tend to be larger than on earth because of the absence of gravity settling. Aboard the ISS, dusts are effectively managed by HEPA filters, although floating dust in newly-arrived modules can be a nuisance. Future missions to the moon and to Mars will present additional challenges because of the possibility that external dust will enter the breathing atmosphere of the habitat and reach the crew's respiratory system. Testing with simulated lunar and Martian dust has shown that these materials are toxic when placed into the lungs of test animals. Defining and evaluating the physical and chemical properties of Martian dusts through robotic missions will challenge our ability to prepare better dust simulants and to determine the risk to crew health from exposure to such dusts.

  18. A Hybrid Vehicle Detection Method Based on Viola-Jones and HOG + SVM from UAV Images

    PubMed Central

    Xu, Yongzheng; Yu, Guizhen; Wang, Yunpeng; Wu, Xinkai; Ma, Yalong

    2016-01-01

    A new hybrid vehicle detection scheme which integrates the Viola-Jones (V-J) and linear SVM classifier with HOG feature (HOG + SVM) methods is proposed for vehicle detection from low-altitude unmanned aerial vehicle (UAV) images. As both V-J and HOG + SVM are sensitive to on-road vehicles’ in-plane rotation, the proposed scheme first adopts a roadway orientation adjustment method, which rotates each UAV image to align the roads with the horizontal direction so the original V-J or HOG + SVM method can be directly applied to achieve fast detection and high accuracy. To address the issue of descending detection speed for V-J and HOG + SVM, the proposed scheme further develops an adaptive switching strategy which sophistically integrates V-J and HOG + SVM methods based on their different descending trends of detection speed to improve detection efficiency. A comprehensive evaluation shows that the switching strategy, combined with the road orientation adjustment method, can significantly improve the efficiency and effectiveness of the vehicle detection from UAV images. The results also show that the proposed vehicle detection method is competitive compared with other existing vehicle detection methods. Furthermore, since the proposed vehicle detection method can be performed on videos captured from moving UAV platforms without the need of image registration or additional road database, it has great potentials of field applications. Future research will be focusing on expanding the current method for detecting other transportation modes such as buses, trucks, motors, bicycles, and pedestrians. PMID:27548179

  19. Displays for future intermediate UAV

    NASA Astrophysics Data System (ADS)

    Desjardins, Daniel; Metzler, James; Blakesley, David; Rister, Courtney; Nuhu, Abdul-Razak

    2008-04-01

    The Dedicated Autonomous Extended Duration Airborne Long-range Utility System (DAEDALUS) is a prototype Unmanned Aerial Vehicle (UAV) that won the 2007 AFRL Commander's Challenge. The purpose of the Commander's Challenge was to find an innovative solution to urgent warfighter needs by designing a UAV with increased persistence for tactical employment of sensors and communication systems. DAEDALUS was chosen as a winning prototype by AFRL, AFMC and SECAF. Follow-on units are intended to fill an intermediate role between currently fielded Tier I and Tier II UAV's. The UAV design discussed in this paper, including sensors and displays, will enter Phase II for Rapid Prototype Development with the intent of developing the design for eventual production. This paper will discuss the DAEDALUS UAV prototype system, with particular focus on its communications, to include the infrared sensor and electro-optical camera, but also displays, specifically man-portable.

  20. Small Whiskbroom Imager for atmospheric compositioN monitorinG (SWING) from an Unmanned Aerial Vehicle (UAV): Results from the 2014 AROMAT campaign

    NASA Astrophysics Data System (ADS)

    Merlaud, Alexis; Tack, Frederik; Constantin, Daniel; Fayt, Caroline; Maes, Jeroen; Mingireanu, Florin; Mocanu, Ionut; Georgescu, Lucian; Van Roozendael, Michel

    2015-04-01

    The Small Whiskbroom Imager for atmospheric compositioN monitorinG (SWING) is an instrument dedicated to atmospheric trace gas retrieval from an Unmanned Aerial Vehicle (UAV). The payload is based on a compact visible spectrometer and a scanning mirror to collect scattered sunlight. Its weight, size, and power consumption are respectively 920 g, 27x12x12 cm3, and 6 W. The custom-built 2.5 m flying wing UAV is electrically powered, has a typical airspeed of 100 km/h, and can operate at a maximum altitude of 3 km. Both the payload and the UAV were developed in the framework of a collaboration between the Belgian Institute for Space Aeronomy (BIRA-IASB) and the Dunarea de Jos University of Galati, Romania. We present here SWING-UAV test flights dedicated to NO2 measurements and performed in Romania on 10 and 11 September 2014, during the Airborne ROmanian Measurements of Aerosols and Trace gases (AROMAT) campaign. The UAV performed 5 flights in the vicinity of the large thermal power station of Turceni (44.67° N, 23.4° E). The UAV was operated in visual range during the campaign, up to 900 m AGL , downwind of the plant and crossing its exhaust plume. The spectra recorded on flight are analyzed with the Differential Optical Absorption Spectroscopy (DOAS) method. The retrieved NO2 Differential Slant Column Densities (DSCDs) are up to 1.5e17 molec/cm2 and reveal the horizontal gradients around the plant. The DSCDs are converted to vertical columns and compared with coincident car-based DOAS measurements. We also present the near-future perspective of the SWING-UAV observation system, which includes flights in 2015 above the Black Sea to quantify ship emissions, the addition of SO2 as a target species, and autopilot flights at higher altitudes to cover a typical satellite pixel extent (10x10 km2).

  1. Balancing search and target response in cooperative unmanned aerial vehicle (UAV) teams.

    PubMed

    Jin, Yan; Liao, Yan; Minai, Ali A; Polycarpou, Marios M

    2006-06-01

    This paper considers a heterogeneous team of cooperating unmanned aerial vehicles (UAVs) drawn from several distinct classes and engaged in a search and action mission over a spatially extended battlefield with targets of several types. During the mission, the UAVs seek to confirm and verifiably destroy suspected targets and discover, confirm, and verifiably destroy unknown targets. The locations of some (or all) targets are unknown a priori, requiring them to be located using cooperative search. In addition, the tasks to be performed at each target location by the team of cooperative UAVs need to be coordinated. The tasks must, therefore, be allocated to UAVs in real time as they arise, while ensuring that appropriate vehicles are assigned to each task. Each class of UAVs has its own sensing and attack capabilities, so the need for appropriate assignment is paramount. In this paper, an extensive dynamic model that captures the stochastic nature of the cooperative search and task assignment problems is developed, and algorithms for achieving a high level of performance are designed. The paper focuses on investigating the value of predictive task assignment as a function of the number of unknown targets and number of UAVs. In particular, it is shown that there is a tradeoff between search and task response in the context of prediction. Based on the results, a hybrid algorithm for switching the use of prediction is proposed, which balances the search and task response. The performance of the proposed algorithms is evaluated through Monte Carlo simulations.

  2. A meta-analysis of human-system interfaces in unmanned aerial vehicle (UAV) swarm management.

    PubMed

    Hocraffer, Amy; Nam, Chang S

    2017-01-01

    A meta-analysis was conducted to systematically evaluate the current state of research on human-system interfaces for users controlling semi-autonomous swarms composed of groups of drones or unmanned aerial vehicles (UAVs). UAV swarms pose several human factors challenges, such as high cognitive demands, non-intuitive behavior, and serious consequences for errors. This article presents findings from a meta-analysis of 27 UAV swarm management papers focused on the human-system interface and human factors concerns, providing an overview of the advantages, challenges, and limitations of current UAV management interfaces, as well as information on how these interfaces are currently evaluated. In general allowing user and mission-specific customization to user interfaces and raising the swarm's level of autonomy to reduce operator cognitive workload are beneficial and improve situation awareness (SA). It is clear more research is needed in this rapidly evolving field.

  3. Aerial surveys and tagging of free-drifting icebergs using an unmanned aerial vehicle (UAV)

    NASA Astrophysics Data System (ADS)

    McGill, P. R.; Reisenbichler, K. R.; Etchemendy, S. A.; Dawe, T. C.; Hobson, B. W.

    2011-06-01

    Ship-based observations of free-drifting icebergs are hindered by the dangers of calving ice. To improve the efficacy and safety of these studies, new unmanned aerial vehicles (UAVs) were developed and then deployed in the Southern Ocean. These inexpensive UAVs were launched and recovered from a ship by scientific personal with a few weeks of flight training. The UAVs sent real-time video back to the ship, allowing researchers to observe conditions in regions of the icebergs not visible from the ship. In addition, the UAVs dropped newly developed global positioning system (GPS) tracking tags, permitting researchers to record the precise position of the icebergs over time. The position reports received from the tags show that the motion of free-drifting icebergs changes rapidly and is a complex combination of both translation and rotation.

  4. A meta-analysis of human-system interfaces in unmanned aerial vehicle (UAV) swarm management.

    PubMed

    Hocraffer, Amy; Nam, Chang S

    2017-01-01

    A meta-analysis was conducted to systematically evaluate the current state of research on human-system interfaces for users controlling semi-autonomous swarms composed of groups of drones or unmanned aerial vehicles (UAVs). UAV swarms pose several human factors challenges, such as high cognitive demands, non-intuitive behavior, and serious consequences for errors. This article presents findings from a meta-analysis of 27 UAV swarm management papers focused on the human-system interface and human factors concerns, providing an overview of the advantages, challenges, and limitations of current UAV management interfaces, as well as information on how these interfaces are currently evaluated. In general allowing user and mission-specific customization to user interfaces and raising the swarm's level of autonomy to reduce operator cognitive workload are beneficial and improve situation awareness (SA). It is clear more research is needed in this rapidly evolving field. PMID:27633199

  5. Survey on the novel hybrid aquatic-aerial amphibious aircraft: Aquatic unmanned aerial vehicle (AquaUAV)

    NASA Astrophysics Data System (ADS)

    Yang, Xingbang; Wang, Tianmiao; Liang, Jianhong; Yao, Guocai; Liu, Miao

    2015-04-01

    The aquatic unmanned aerial vehicle (AquaUAV), a kind of vehicle that can operate both in the air and the water, has been regarded as a new breakthrough to broaden the application scenario of UAV. Wide application prospects in military and civil field are more than bright, therefore many institutions have focused on the development of such a vehicle. However, due to the significant difference of the physical properties between the air and the water, it is rather difficult to design a fully-featured AquaUAV. Until now, majority of partially-featured AquaUAVs have been developed and used to verify the feasibility of an aquatic-aerial vehicle. In the present work, we classify the current partially-featured AquaUAV into three categories from the scope of the whole UAV field, i.e., the seaplane UAV, the submarine-launched UAV, and the submersible UAV. Then the recent advancements and common characteristics of the three kinds of AquaUAVs are reviewed in detail respectively. Then the applications of bionics in the design of AquaUAV, the transition mode between the air and the water, the morphing wing structure for air-water adaptation, and the power source and the propulsion type are summarized and discussed. The tradeoff analyses for different transition methods between the air and the water are presented. Furthermore, it indicates that applying the bionics into the design and development of the AquaUAV will be essential and significant. Finally, the significant technical challenges for the AquaUAV to change from a conception to a practical prototype are indicated.

  6. Assessment of lightweight mobile nuclear power systems. [for airborne vehicles

    NASA Technical Reports Server (NTRS)

    Anderson, J. L.; Rom, F. E.

    1973-01-01

    A review was made of lightweight mobile nuclear power systems (LMNPS). Data cover technical feasibility studies of LMNPS and airborne vehicles, mission studies, and non-technical conditions that are required to develop and use LMNPS.

  7. Offutt Air Force Base, Looking Glass Airborne Command Post, Vehicle ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Offutt Air Force Base, Looking Glass Airborne Command Post, Vehicle Refueling Station, Northeast of AGE Storage Facility at far northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  8. Acquisition, orthorectification, and object-based classification of unmanned aerial vehicle (UAV) imagery for rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we examine the potential of using a small unmanned aerial vehicle (UAV) for rangeland inventory, assessment and monitoring. Imagery with 8-cm resolution was acquired over 290 ha in southwestern Idaho. We developed a semi-automated orthorectification procedure suitable for handling lar...

  9. First results for an image processing workflow for hyperspatial imagery acquired with a low-cost unmanned aerial vehicle (UAV).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Very high-resolution images from unmanned aerial vehicles (UAVs) have great potential for use in rangeland monitoring and assessment, because the imagery fills the gap between ground-based observations and remotely sensed imagery from aerial or satellite sensors. However, because UAV imagery is ofte...

  10. Moments of Inertia: Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID)

    NASA Technical Reports Server (NTRS)

    Haro, Helida C.

    2010-01-01

    The objective of this research effort is to determine the most appropriate, cost efficient, and effective method to utilize for finding moments of inertia for the Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID). A moment is a measure of the body's tendency to turn about its center of gravity (CG) and inertia is the resistance of a body to changes in its momentum. Therefore, the moment of inertia (MOI) is a body's resistance to change in rotation about its CG. The inertial characteristics of an UAV have direct consequences on aerodynamics, propulsion, structures, and control. Therefore, it is imperative to determine the precise inertial characteristics of the DROID.

  11. Moments of Inertia - Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID)

    NASA Technical Reports Server (NTRS)

    Haro, Helida C.

    2010-01-01

    The objective of this research effort is to determine the most appropriate, cost efficient, and effective method to utilize for finding moments of inertia for the Uninhabited Aerial Vehicle (UAV) Dryden Remotely Operated Integrated Drone (DROID). A moment is a measure of the body's tendency to turn about its center of gravity (CG) and inertia is the resistance of a body to changes in its momentum. Therefore, the moment of inertia (MOI) is a body's resistance to change in rotation about its CG. The inertial characteristics of an UAV have direct consequences on aerodynamics, propulsion, structures, and control. Therefore, it is imperative to determine the precise inertial characteristics of the DROID.

  12. GPS navigation algorithms for Autonomous Airborne Refueling of Unmanned Air Vehicles

    NASA Astrophysics Data System (ADS)

    Khanafseh, Samer Mahmoud

    Unmanned Air Vehicles (UAVs) have recently generated great interest because of their potential to perform hazardous missions without risking loss of life. If autonomous airborne refueling is possible for UAVs, mission range and endurance will be greatly enhanced. However, concerns about UAV-tanker proximity, dynamic mobility and safety demand that the relative navigation system meets stringent requirements on accuracy, integrity, and continuity. In response, this research focuses on developing high-performance GPS-based navigation architectures for Autonomous Airborne Refueling (AAR) of UAVs. The AAR mission is unique because of the potentially severe sky blockage introduced by the tanker. To address this issue, a high-fidelity dynamic sky blockage model was developed and experimentally validated. In addition, robust carrier phase differential GPS navigation algorithms were derived, including a new method for high-integrity reacquisition of carrier cycle ambiguities for recently-blocked satellites. In order to evaluate navigation performance, world-wide global availability and sensitivity covariance analyses were conducted. The new navigation algorithms were shown to be sufficient for turn-free scenarios, but improvement in performance was necessary to meet the difficult requirements for a general refueling mission with banked turns. Therefore, several innovative methods were pursued to enhance navigation performance. First, a new theoretical approach was developed to quantify the position-domain integrity risk in cycle ambiguity resolution problems. A mechanism to implement this method with partially-fixed cycle ambiguity vectors was derived, and it was used to define tight upper bounds on AAR navigation integrity risk. A second method, where a new algorithm for optimal fusion of measurements from multiple antennas was developed, was used to improve satellite coverage in poor visibility environments such as in AAR. Finally, methods for using data-link extracted

  13. Q-learning approach to automated unmanned air vehicle (UAV) demining

    NASA Astrophysics Data System (ADS)

    Ferrari, Silvia; Daugherty, Greyson

    2010-04-01

    This paper develops a Q-learning approach to Unmanned Air Vehicle (UAV) navigation, or path planning, for sensing applications in which an infrared (IR) sensor or camera is installed onboard the UAV for the purpose of detecting and classifying multiple, stationary ground targets. The problem can be considered as a geometric sensor-path planning problem, because the geometry and position of the sensor's field of view (FOV) determines what targets can be detected and classified at any given time. The advantage of this approach over existing path planning techniques is that the optimal guidance policy is learned via the Q-function, without explicit knowledge of the system models and environmental conditions. The approach is demonstrated through a demining application in which a UAV-based IR sensor is capable of determining the optimal altitude for properly detecting and classifying targets buried in a complex region of interest.

  14. Vehicle tracking in wide area motion imagery from an airborne platform

    NASA Astrophysics Data System (ADS)

    van Eekeren, Adam W. M.; van Huis, Jasper R.; Eendebak, Pieter T.; Baan, Jan

    2015-10-01

    Airborne platforms, such as UAV's, with Wide Area Motion Imagery (WAMI) sensors can cover multiple square kilometers and produce large amounts of video data. Analyzing all data for information need purposes becomes increasingly labor-intensive for an image analyst. Furthermore, the capacity of the datalink in operational areas may be inadequate to transfer all data to the ground station. Automatic detection and tracking of people and vehicles enables to send only the most relevant footage to the ground station and assists the image analysts in effective data searches. In this paper, we propose a method for detecting and tracking vehicles in high-resolution WAMI images from a moving airborne platform. For the vehicle detection we use a cascaded set of classifiers, using an Adaboost training algorithm on Haar features. This detector works on individual images and therefore does not depend on image motion stabilization. For the vehicle tracking we use a local template matching algorithm. This approach has two advantages. In the first place, it does not depend on image motion stabilization and it counters the inaccuracy of the GPS data that is embedded in the video data. In the second place, it can find matches when the vehicle detector would miss a certain detection. This results in long tracks even when the imagery is of low frame-rate. In order to minimize false detections, we also integrate height information from a 3D reconstruction that is created from the same images. By using the locations of buildings and roads, we are able to filter out false detections and increase the performance of the tracker. In this paper we show that the vehicle tracks can also be used to detect more complex events, such as traffic jams and fast moving vehicles. This enables the image analyst to do a faster and more effective search of the data.

  15. Data Acquisition (DAQ) system dedicated for remote sensing applications on Unmanned Aerial Vehicles (UAV)

    NASA Astrophysics Data System (ADS)

    Keleshis, C.; Ioannou, S.; Vrekoussis, M.; Levin, Z.; Lange, M. A.

    2014-08-01

    Continuous advances in unmanned aerial vehicles (UAV) and the increased complexity of their applications raise the demand for improved data acquisition systems (DAQ). These improvements may comprise low power consumption, low volume and weight, robustness, modularity and capability to interface with various sensors and peripherals while maintaining the high sampling rates and processing speeds. Such a system has been designed and developed and is currently integrated on the Autonomous Flying Platforms for Atmospheric and Earth Surface Observations (APAESO/NEA-YΠOΔOMH/NEKΠ/0308/09) however, it can be easily adapted to any UAV or any other mobile vehicle. The system consists of a single-board computer with a dual-core processor, rugged surface-mount memory and storage device, analog and digital input-output ports and many other peripherals that enhance its connectivity with various sensors, imagers and on-board devices. The system is powered by a high efficiency power supply board. Additional boards such as frame-grabbers, differential global positioning system (DGPS) satellite receivers, general packet radio service (3G-4G-GPRS) modems for communication redundancy have been interfaced to the core system and are used whenever there is a mission need. The onboard DAQ system can be preprogrammed for automatic data acquisition or it can be remotely operated during the flight from the ground control station (GCS) using a graphical user interface (GUI) which has been developed and will also be presented in this paper. The unique design of the GUI and the DAQ system enables the synchronized acquisition of a variety of scientific and UAV flight data in a single core location. The new DAQ system and the GUI have been successfully utilized in several scientific UAV missions. In conclusion, the novel DAQ system provides the UAV and the remote-sensing community with a new tool capable of reliably acquiring, processing, storing and transmitting data from any sensor integrated

  16. Evaluation of unmanned aerial vehicle (UAV) imagery to model vegetation heights in Hulun Buir grassland ecosystem

    NASA Astrophysics Data System (ADS)

    Wang, D.; Xin, X.; Li, Z.

    2015-12-01

    Vertical vegetation structure in grassland ecosystem is needed to assess grassland health and monitor available forage for livestock and wildlife habitat. Traditional ground-based field methods for measuring vegetation heights are time consuming. Most emerging airborne remote sensing techniques capable of measuring surface and vegetation height (e.g., LIDAR) are too expensive to apply at broad scales. Aerial or spaceborne stereo imagery has the cost advantage for mapping height of tall vegetation, such as forest. However, the accuracy and uncertainty of using stereo imagery for modeling heights of short vegetation, such as grass (generally lower than 50cm) needs to be investigated. In this study, 2.5-cm resolution UAV stereo imagery are used to model vegetation heights in Hulun Buir grassland ecosystem. Strong correlations were observed (r > 0.9) between vegetation heights derived from UAV stereo imagery and those field-measured ones at individual and plot level. However, vegetation heights tended to be underestimated in the imagery especially for those areas with high vegetation coverage. The strong correlations between field-collected vegetation heights and metrics derived from UAV stereo imagery suggest that UAV stereo imagery can be used to estimate short vegetation heights such as those in grassland ecosystem. Future work will be needed to verify the extensibility of the methods to other sites and vegetation types.

  17. High Resolution Airborne Laser Scanning and Hyperspectral Imaging with a Small Uav Platform

    NASA Astrophysics Data System (ADS)

    Gallay, Michal; Eck, Christoph; Zgraggen, Carlo; Kaňuk, Ján; Dvorný, Eduard

    2016-06-01

    The capabilities of unmanned airborne systems (UAS) have become diverse with the recent development of lightweight remote sensing instruments. In this paper, we demonstrate our custom integration of the state-of-the-art technologies within an unmanned aerial platform capable of high-resolution and high-accuracy laser scanning, hyperspectral imaging, and photographic imaging. The technological solution comprises the latest development of a completely autonomous, unmanned helicopter by Aeroscout, the Scout B1-100 UAV helicopter. The helicopter is powered by a gasoline two-stroke engine and it allows for integrating 18 kg of a customized payload unit. The whole system is modular providing flexibility of payload options, which comprises the main advantage of the UAS. The UAS integrates two kinds of payloads which can be altered. Both payloads integrate a GPS/IMU with a dual GPS antenna configuration provided by OXTS for accurate navigation and position measurements during the data acquisition. The first payload comprises a VUX-1 laser scanner by RIEGL and a Sony A6000 E-Mount photo camera. The second payload for hyperspectral scanning integrates a push-broom imager AISA KESTREL 10 by SPECIM. The UAS was designed for research of various aspects of landscape dynamics (landslides, erosion, flooding, or phenology) in high spectral and spatial resolution.

  18. Unmanned aerial vehicle (UAV) operated megapixel spectral camera

    NASA Astrophysics Data System (ADS)

    Mäkynen, Jussi; Holmlund, Christer; Saari, Heikki; Ojala, Kai; Antila, Tapani

    2011-11-01

    VTT Technical Research Centre of Finland has developed a lightweight Fabry-Perot interferometer based hyperspectral imager weighting only 400 g which makes it compatible with various small UAV platforms. The concept of the hyperspectral imager has been published in SPIE Proc. 74741 and 76682. This UAV spectral imager is capable of recording 5 Mpix multispectral data in the wavelength range of 500 - 900 nm at resolutions of 10-40 nm, Full-Width-Half-Maximum (FWHM). An internal memory buffer allows 16 Mpix of image data to be stored during one image burst. The user can configure the system to take either three 5 Mpix images or up to 54 VGA resolution images with each triggering. Each image contains data from one, two or three wavelength bands which can be separated during post processing. This allows a maximum of 9 spectral bands to be stored in high spatial resolution mode or up to 162 spectral bands in VGA-mode during each image burst. Image data is stored in a compact flash memory card which provides the mass storage for the imager. The field of view of the system is 26° × 36° and the ground pixel size at 150 m flying altitude is around 40 mm in high-resolution mode. The design, calibration and test flight results will be presented.

  19. Configuration and specifications of an Unmanned Aerial Vehicle (UAV) for early site specific weed management.

    PubMed

    Torres-Sánchez, Jorge; López-Granados, Francisca; De Castro, Ana Isabel; Peña-Barragán, José Manuel

    2013-01-01

    A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches).

  20. Unmanned aerial vehicles (UAVs) for surveying marine fauna: a dugong case study.

    PubMed

    Hodgson, Amanda; Kelly, Natalie; Peel, David

    2013-01-01

    Aerial surveys of marine mammals are routinely conducted to assess and monitor species' habitat use and population status. In Australia, dugongs (Dugong dugon) are regularly surveyed and long-term datasets have formed the basis for defining habitat of high conservation value and risk assessments of human impacts. Unmanned aerial vehicles (UAVs) may facilitate more accurate, human-risk free, and cheaper aerial surveys. We undertook the first Australian UAV survey trial in Shark Bay, western Australia. We conducted seven flights of the ScanEagle UAV, mounted with a digital SLR camera payload. During each flight, ten transects covering a 1.3 km(2) area frequently used by dugongs, were flown at 500, 750 and 1000 ft. Image (photograph) capture was controlled via the Ground Control Station and the capture rate was scheduled to achieve a prescribed 10% overlap between images along transect lines. Images were manually reviewed post hoc for animals and scored according to sun glitter, Beaufort Sea state and turbidity. We captured 6243 images, 627 containing dugongs. We also identified whales, dolphins, turtles and a range of other fauna. Of all possible dugong sightings, 95% (CI = 90%, 98%) were subjectively classed as 'certain' (unmistakably dugongs). Neither our dugong sighting rate, nor our ability to identify dugongs with certainty, were affected by UAV altitude. Turbidity was the only environmental variable significantly affecting the dugong sighting rate. Our results suggest that UAV systems may not be limited by sea state conditions in the same manner as sightings from manned surveys. The overlap between images proved valuable for detecting animals that were masked by sun glitter in the corners of images, and identifying animals initially captured at awkward body angles. This initial trial of a basic camera system has successfully demonstrated that the ScanEagle UAV has great potential as a tool for marine mammal aerial surveys.

  1. Unmanned aerial vehicles (UAVs) for surveying marine fauna: a dugong case study.

    PubMed

    Hodgson, Amanda; Kelly, Natalie; Peel, David

    2013-01-01

    Aerial surveys of marine mammals are routinely conducted to assess and monitor species' habitat use and population status. In Australia, dugongs (Dugong dugon) are regularly surveyed and long-term datasets have formed the basis for defining habitat of high conservation value and risk assessments of human impacts. Unmanned aerial vehicles (UAVs) may facilitate more accurate, human-risk free, and cheaper aerial surveys. We undertook the first Australian UAV survey trial in Shark Bay, western Australia. We conducted seven flights of the ScanEagle UAV, mounted with a digital SLR camera payload. During each flight, ten transects covering a 1.3 km(2) area frequently used by dugongs, were flown at 500, 750 and 1000 ft. Image (photograph) capture was controlled via the Ground Control Station and the capture rate was scheduled to achieve a prescribed 10% overlap between images along transect lines. Images were manually reviewed post hoc for animals and scored according to sun glitter, Beaufort Sea state and turbidity. We captured 6243 images, 627 containing dugongs. We also identified whales, dolphins, turtles and a range of other fauna. Of all possible dugong sightings, 95% (CI = 90%, 98%) were subjectively classed as 'certain' (unmistakably dugongs). Neither our dugong sighting rate, nor our ability to identify dugongs with certainty, were affected by UAV altitude. Turbidity was the only environmental variable significantly affecting the dugong sighting rate. Our results suggest that UAV systems may not be limited by sea state conditions in the same manner as sightings from manned surveys. The overlap between images proved valuable for detecting animals that were masked by sun glitter in the corners of images, and identifying animals initially captured at awkward body angles. This initial trial of a basic camera system has successfully demonstrated that the ScanEagle UAV has great potential as a tool for marine mammal aerial surveys. PMID:24223967

  2. Configuration and specifications of an Unmanned Aerial Vehicle (UAV) for early site specific weed management.

    PubMed

    Torres-Sánchez, Jorge; López-Granados, Francisca; De Castro, Ana Isabel; Peña-Barragán, José Manuel

    2013-01-01

    A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches). PMID:23483997

  3. Unmanned Aerial Vehicles (UAVs) for Surveying Marine Fauna: A Dugong Case Study

    PubMed Central

    Hodgson, Amanda; Kelly, Natalie; Peel, David

    2013-01-01

    Aerial surveys of marine mammals are routinely conducted to assess and monitor species’ habitat use and population status. In Australia, dugongs (Dugong dugon) are regularly surveyed and long-term datasets have formed the basis for defining habitat of high conservation value and risk assessments of human impacts. Unmanned aerial vehicles (UAVs) may facilitate more accurate, human-risk free, and cheaper aerial surveys. We undertook the first Australian UAV survey trial in Shark Bay, western Australia. We conducted seven flights of the ScanEagle UAV, mounted with a digital SLR camera payload. During each flight, ten transects covering a 1.3 km2 area frequently used by dugongs, were flown at 500, 750 and 1000 ft. Image (photograph) capture was controlled via the Ground Control Station and the capture rate was scheduled to achieve a prescribed 10% overlap between images along transect lines. Images were manually reviewed post hoc for animals and scored according to sun glitter, Beaufort Sea state and turbidity. We captured 6243 images, 627 containing dugongs. We also identified whales, dolphins, turtles and a range of other fauna. Of all possible dugong sightings, 95% (CI = 90%, 98%) were subjectively classed as ‘certain’ (unmistakably dugongs). Neither our dugong sighting rate, nor our ability to identify dugongs with certainty, were affected by UAV altitude. Turbidity was the only environmental variable significantly affecting the dugong sighting rate. Our results suggest that UAV systems may not be limited by sea state conditions in the same manner as sightings from manned surveys. The overlap between images proved valuable for detecting animals that were masked by sun glitter in the corners of images, and identifying animals initially captured at awkward body angles. This initial trial of a basic camera system has successfully demonstrated that the ScanEagle UAV has great potential as a tool for marine mammal aerial surveys. PMID:24223967

  4. Configuration and Specifications of an Unmanned Aerial Vehicle (UAV) for Early Site Specific Weed Management

    PubMed Central

    Torres-Sánchez, Jorge; López-Granados, Francisca; De Castro, Ana Isabel; Peña-Barragán, José Manuel

    2013-01-01

    A new aerial platform has risen recently for image acquisition, the Unmanned Aerial Vehicle (UAV). This article describes the technical specifications and configuration of a UAV used to capture remote images for early season site- specific weed management (ESSWM). Image spatial and spectral properties required for weed seedling discrimination were also evaluated. Two different sensors, a still visible camera and a six-band multispectral camera, and three flight altitudes (30, 60 and 100 m) were tested over a naturally infested sunflower field. The main phases of the UAV workflow were the following: 1) mission planning, 2) UAV flight and image acquisition, and 3) image pre-processing. Three different aspects were needed to plan the route: flight area, camera specifications and UAV tasks. The pre-processing phase included the correct alignment of the six bands of the multispectral imagery and the orthorectification and mosaicking of the individual images captured in each flight. The image pixel size, area covered by each image and flight timing were very sensitive to flight altitude. At a lower altitude, the UAV captured images of finer spatial resolution, although the number of images needed to cover the whole field may be a limiting factor due to the energy required for a greater flight length and computational requirements for the further mosaicking process. Spectral differences between weeds, crop and bare soil were significant in the vegetation indices studied (Excess Green Index, Normalised Green-Red Difference Index and Normalised Difference Vegetation Index), mainly at a 30 m altitude. However, greater spectral separability was obtained between vegetation and bare soil with the index NDVI. These results suggest that an agreement among spectral and spatial resolutions is needed to optimise the flight mission according to every agronomical objective as affected by the size of the smaller object to be discriminated (weed plants or weed patches). PMID:23483997

  5. Automated UAV-based mapping for airborne reconnaissance and video exploitation

    NASA Astrophysics Data System (ADS)

    Se, Stephen; Firoozfam, Pezhman; Goldstein, Norman; Wu, Linda; Dutkiewicz, Melanie; Pace, Paul; Naud, J. L. Pierre

    2009-05-01

    Airborne surveillance and reconnaissance are essential for successful military missions. Such capabilities are critical for force protection, situational awareness, mission planning, damage assessment and others. UAVs gather huge amount of video data but it is extremely labour-intensive for operators to analyse hours and hours of received data. At MDA, we have developed a suite of tools towards automated video exploitation including calibration, visualization, change detection and 3D reconstruction. The on-going work is to improve the robustness of these tools and automate the process as much as possible. Our calibration tool extracts and matches tie-points in the video frames incrementally to recover the camera calibration and poses, which are then refined by bundle adjustment. Our visualization tool stabilizes the video, expands its field-of-view and creates a geo-referenced mosaic from the video frames. It is important to identify anomalies in a scene, which may include detecting any improvised explosive devices (IED). However, it is tedious and difficult to compare video clips to look for differences manually. Our change detection tool allows the user to load two video clips taken from two passes at different times and flags any changes between them. 3D models are useful for situational awareness, as it is easier to understand the scene by visualizing it in 3D. Our 3D reconstruction tool creates calibrated photo-realistic 3D models from video clips taken from different viewpoints, using both semi-automated and automated approaches. The resulting 3D models also allow distance measurements and line-of- sight analysis.

  6. Unmanned Aerial Vehicle (UAV) associated DTM quality evaluation and hazard assessment

    NASA Astrophysics Data System (ADS)

    Huang, Mei-Jen; Chen, Shao-Der; Chao, Yu-Jui; Chiang, Yi-Lin; Chang, Kuo-Jen

    2014-05-01

    Taiwan, due to the high seismicity and high annual rainfall, numerous landslides triggered every year and severe impacts affect the island. Concerning to the catastrophic landslides, the key information of landslide, including range of landslide, volume estimation and the subsequent evolution are important when analyzing the triggering mechanism, hazard assessment and mitigation. Thus, the morphological analysis gives a general overview for the landslides and been considered as one of the most fundamental information. We try to integrate several technologies, especially by Unmanned Aerial Vehicle (UAV) and multi-spectral camera, to decipher the consequence and the potential hazard, and the social impact. In recent years, the remote sensing technology improves rapidly, providing a wide range of image, essential and precious information. Benefited of the advancing of informatics, remote-sensing and electric technologies, the Unmanned Aerial Vehicle (UAV) photogrammetry mas been improve significantly. The study tries to integrate several methods, including, 1) Remote-sensing images gathered by Unmanned Aerial Vehicle (UAV) and by aerial photos taken in different periods; 2) field in-situ geologic investigation; 3) Differential GPS, RTK GPS and Ground LiDAR field in-site geoinfomatics measurements; 4) Construct the DTMs before and after landslide, as well as the subsequent periods using UAV and aerial photos; 5) Discrete element method should be applied to understand the geomaterial composing the slope failure, for predicting earthquake-induced and rainfall-induced landslides displacement. First at all, we evaluate the Microdrones MD4-1000 UAV airphotos derived Digital Terrain Model (DTM). The ground resolution of the DSM point cloud of could be as high as 10 cm. By integrated 4 ground control point within an area of 56 hectares, compared with LiDAR DSM and filed RTK-GPS surveying, the mean error is as low as 6cm with a standard deviation of 17cm. The quality of the

  7. Small UAV Research and Evolution in Long Endurance Electric Powered Vehicles

    NASA Technical Reports Server (NTRS)

    Logan, Michael J.; Chu, Julio; Motter, Mark A.; Carter, Dennis L.; Ol, Michael; Zeune, Cale

    2007-01-01

    This paper describes recent research into the advancement of small, electric powered unmanned aerial vehicle (UAV) capabilities. Specifically, topics include the improvements made in battery technology, design methodologies, avionics architectures and algorithms, materials and structural concepts, propulsion system performance prediction, and others. The results of prototype vehicle designs and flight tests are discussed in the context of their usefulness in defining and validating progress in the various technology areas. Further areas of research need are also identified. These include the need for more robust operating regimes (wind, gust, etc.), and continued improvement in payload fraction vs. endurance.

  8. Weed mapping in early-season maize fields using object-based analysis of unmanned aerial vehicle (UAV) images.

    PubMed

    Peña, José Manuel; Torres-Sánchez, Jorge; de Castro, Ana Isabel; Kelly, Maggi; López-Granados, Francisca

    2013-01-01

    The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was developed on a series of UAV images using a six-band multispectral camera (visible and near-infrared range) with the ultimate objective of generating a weed map in an experimental maize field in Spain. The OBIA procedure combines several contextual, hierarchical and object-based features and consists of three consecutive phases: 1) classification of crop rows by application of a dynamic and auto-adaptive classification approach, 2) discrimination of crops and weeds on the basis of their relative positions with reference to the crop rows, and 3) generation of a weed infestation map in a grid structure. The estimation of weed coverage from the image analysis yielded satisfactory results. The relationship of estimated versus observed weed densities had a coefficient of determination of r(2)=0.89 and a root mean square error of 0.02. A map of three categories of weed coverage was produced with 86% of overall accuracy. In the experimental field, the area free of weeds was 23%, and the area with low weed coverage (<5% weeds) was 47%, which indicated a high potential for reducing herbicide application or other weed operations. The OBIA procedure computes multiple data and statistics derived from the classification outputs, which permits calculation of herbicide requirements and estimation of the overall cost of weed management operations in advance.

  9. Weed mapping in early-season maize fields using object-based analysis of unmanned aerial vehicle (UAV) images.

    PubMed

    Peña, José Manuel; Torres-Sánchez, Jorge; de Castro, Ana Isabel; Kelly, Maggi; López-Granados, Francisca

    2013-01-01

    The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was developed on a series of UAV images using a six-band multispectral camera (visible and near-infrared range) with the ultimate objective of generating a weed map in an experimental maize field in Spain. The OBIA procedure combines several contextual, hierarchical and object-based features and consists of three consecutive phases: 1) classification of crop rows by application of a dynamic and auto-adaptive classification approach, 2) discrimination of crops and weeds on the basis of their relative positions with reference to the crop rows, and 3) generation of a weed infestation map in a grid structure. The estimation of weed coverage from the image analysis yielded satisfactory results. The relationship of estimated versus observed weed densities had a coefficient of determination of r(2)=0.89 and a root mean square error of 0.02. A map of three categories of weed coverage was produced with 86% of overall accuracy. In the experimental field, the area free of weeds was 23%, and the area with low weed coverage (<5% weeds) was 47%, which indicated a high potential for reducing herbicide application or other weed operations. The OBIA procedure computes multiple data and statistics derived from the classification outputs, which permits calculation of herbicide requirements and estimation of the overall cost of weed management operations in advance. PMID:24146963

  10. Weed Mapping in Early-Season Maize Fields Using Object-Based Analysis of Unmanned Aerial Vehicle (UAV) Images

    PubMed Central

    Peña, José Manuel; Torres-Sánchez, Jorge; de Castro, Ana Isabel; Kelly, Maggi; López-Granados, Francisca

    2013-01-01

    The use of remote imagery captured by unmanned aerial vehicles (UAV) has tremendous potential for designing detailed site-specific weed control treatments in early post-emergence, which have not possible previously with conventional airborne or satellite images. A robust and entirely automatic object-based image analysis (OBIA) procedure was developed on a series of UAV images using a six-band multispectral camera (visible and near-infrared range) with the ultimate objective of generating a weed map in an experimental maize field in Spain. The OBIA procedure combines several contextual, hierarchical and object-based features and consists of three consecutive phases: 1) classification of crop rows by application of a dynamic and auto-adaptive classification approach, 2) discrimination of crops and weeds on the basis of their relative positions with reference to the crop rows, and 3) generation of a weed infestation map in a grid structure. The estimation of weed coverage from the image analysis yielded satisfactory results. The relationship of estimated versus observed weed densities had a coefficient of determination of r2=0.89 and a root mean square error of 0.02. A map of three categories of weed coverage was produced with 86% of overall accuracy. In the experimental field, the area free of weeds was 23%, and the area with low weed coverage (<5% weeds) was 47%, which indicated a high potential for reducing herbicide application or other weed operations. The OBIA procedure computes multiple data and statistics derived from the classification outputs, which permits calculation of herbicide requirements and estimation of the overall cost of weed management operations in advance. PMID:24146963

  11. Airborne Simulation of Launch Vehicle Dynamics

    NASA Technical Reports Server (NTRS)

    Gilligan, Eric T.; Miller, Christopher J.; Hanson, Curtis E.; Orr, Jeb S.

    2014-01-01

    In this paper we present a technique for approximating the short-period dynamics of an exploration-class launch vehicle during flight test with a high-performance surrogate aircraft in relatively benign endoatmospheric flight conditions. The surrogate vehicle relies upon a nonlinear dynamic inversion scheme with proportional-integral feedback to drive a subset of the aircraft states into coincidence with the states of a time-varying reference model that simulates the unstable rigid body dynamics, servodynamics, and parasitic elastic and sloshing dynamics of the launch vehicle. The surrogate aircraft flies a constant pitch rate trajectory to approximate the boost phase gravity-turn ascent, and the aircraft's closed-loop bandwidth is sufficient to simulate the launch vehicle's fundamental lateral bending and sloshing modes by exciting the rigid body dynamics of the aircraft. A novel control allocation scheme is employed to utilize the aircraft's relatively fast control effectors in inducing various failure modes for the purposes of evaluating control system performance. Sufficient dynamic similarity is achieved such that the control system under evaluation is optimized for the full-scale vehicle with no changes to its parameters, and pilot-control system interaction studies can be performed to characterize the effects of guidance takeover during boost. High-fidelity simulation and flight test results are presented that demonstrate the efficacy of the design in simulating the Space Launch System (SLS) launch vehicle dynamics using NASA Dryden Flight Research Center's Full-scale Advanced Systems Testbed (FAST), a modified F/A-18 airplane, over a range of scenarios designed to stress the SLS's adaptive augmenting control (AAC) algorithm.

  12. Airborne Simulation of Launch Vehicle Dynamics

    NASA Technical Reports Server (NTRS)

    Miller, Christopher J.; Orr, Jeb S.; Hanson, Curtis E.; Gilligan, Eric T.

    2015-01-01

    In this paper we present a technique for approximating the short-period dynamics of an exploration-class launch vehicle during flight test with a high-performance surrogate aircraft in relatively benign endoatmospheric flight conditions. The surrogate vehicle relies upon a nonlinear dynamic inversion scheme with proportional-integral feedback to drive a subset of the aircraft states into coincidence with the states of a time-varying reference model that simulates the unstable rigid body dynamics, servodynamics, and parasitic elastic and sloshing dynamics of the launch vehicle. The surrogate aircraft flies a constant pitch rate trajectory to approximate the boost phase gravity turn ascent, and the aircraft's closed-loop bandwidth is sufficient to simulate the launch vehicle's fundamental lateral bending and sloshing modes by exciting the rigid body dynamics of the aircraft. A novel control allocation scheme is employed to utilize the aircraft's relatively fast control effectors in inducing various failure modes for the purposes of evaluating control system performance. Sufficient dynamic similarity is achieved such that the control system under evaluation is configured for the full-scale vehicle with no changes to its parameters, and pilot-control system interaction studies can be performed to characterize the effects of guidance takeover during boost. High-fidelity simulation and flight-test results are presented that demonstrate the efficacy of the design in simulating the Space Launch System (SLS) launch vehicle dynamics using the National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center Fullscale Advanced Systems Testbed (FAST), a modified F/A-18 airplane (McDonnell Douglas, now The Boeing Company, Chicago, Illinois), over a range of scenarios designed to stress the SLS's Adaptive Augmenting Control (AAC) algorithm.

  13. Airborne tracking resolution requirements for urban vehicles

    NASA Astrophysics Data System (ADS)

    Robinson, Aaron L.; Miller, Brian; Richardson, Phil; Ra, Chun

    2008-04-01

    This paper details the development, experimentation, collected data and the results of research designed to gain an understanding of the temporal and spatial image collection guidelines for tracking urban vehicles. More specifically, a quantitative understanding of the relationship between human observer performance and the spatial and temporal resolution is sought. Performance is measured as a function of the number of video frames per second, imager spatial resolution and the ability of the observer to accurately determine the destination of a moving vehicle target. The research is restricted to data and imagery collected from altitudes typical of modern low to mid altitude persistent surveillance platforms using a wide field of view. The ability of the human observer to perform an unaided track of the vehicle was determined by their completion of carefully designed perception experiments. In these experiments, the observers were presented with simulated imagery from Night Vision's EOSim urban terrain simulator. The details of the simulated targets and backgrounds, the design of the experiments and their associated results are included in this treatment.

  14. Lessons Learned from NASA UAV Science Demonstration Program Missions

    NASA Technical Reports Server (NTRS)

    Wegener, Steven S.; Schoenung, Susan M.

    2003-01-01

    During the summer of 2002, two airborne missions were flown as part of a NASA Earth Science Enterprise program to demonstrate the use of uninhabited aerial vehicles (UAVs) to perform earth science. One mission, the Altus Cumulus Electrification Study (ACES), successfully measured lightning storms in the vicinity of Key West, Florida, during storm season using a high-altitude Altus(TM) UAV. In the other, a solar-powered UAV, the Pathfinder Plus, flew a high-resolution imaging mission over coffee fields in Kauai, Hawaii, to help guide the harvest.

  15. Effectiveness of bomber deployed autonomous airborne vehicles in finding rail mobile SS-24s

    SciTech Connect

    Abey, A.E.; Erickson, S.A.; Norquist, P.D.

    1990-08-01

    Computer simulation predictions of the effectiveness of autonomous airborne vehicles in finding rail mobile SS-24s are presented. Effectiveness is discussed for several autonomous airborne vehicle endurances and survivabilities for the search area southwest of Moscow. The effect of where the Soviets place the SS-24s on the rail network was also investigated. The simulation predicts significant variations in the ability of a multi-autonomous airborne vehicle system to find SS-24s with these parameters. 12 figs., 1 tab.

  16. A procedure for orthorectification of sub-decimeter resolution imagery obtained with an unmanned aerial vehicle (UAV)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Digital aerial photography acquired with unmanned aerial vehicles (UAVs) has great value for resource management due to the flexibility and relatively low cost for image acquisition, and very high resolution imagery (5 cm) which allows for mapping bare soil and vegetation types, structure and patter...

  17. Fiber Bragg Grating Sensor/Systems for In-Flight Wing Shape Monitoring of Unmanned Aerial Vehicles (UAVs)

    NASA Technical Reports Server (NTRS)

    Parker, Allen; Richards, Lance; Ko, William; Piazza, Anthony; Tran, Van

    2006-01-01

    A viewgraph presentation describing an in-flight wing shape measurement system based on fiber bragg grating sensors for use in Unmanned Aerial Vehicles (UAV) is shown. The topics include: 1) MOtivation; 2) Objective; 3) Background; 4) System Design; 5) Ground Testing; 6) Future Work; and 7) Conclusions

  18. Using an Unmanned Aerial Vehicle (UAV) to capture ancient seismic offsets along the Altyn Tagh fault

    NASA Astrophysics Data System (ADS)

    Gao, M.; Xu, X.; Tapponnier, P.; van der Woerd, J.; Klinger, Y.; Derrien, A.; Bradley, K. E.

    2015-12-01

    High resolution topographic data is a key ingredient to assess the amplitude of seismic displacements along strike-slip fault. For faults that slip during earthquakes with centennial to millennial recurrence time, erosion smoothes out the sharpness of both geomorphic markers and surface breaks. Co-registred, high resolution digital elevation models and ground images are thus necessary to reconstruct past displacements and deformations along faults. The recent explosion in centimeter resolution topographic data obtained by unmanned aerial vehicle (UAV) raises the possibility of mapping geomorphic offsets of active faults with unprecedented accuracy. Here we tested the technique to obtain high-resolution images and generate topographic data along the Altyn Tagh fault, main active strike-slip fault along the northern edge of Tibet. The existence of spectacular scarps, combined with the low level of instrumental seismicity and lack of well documented historical events requires especialy detailed studies of surface faulting. At several sites along the Altun segment of the fault we reconstruct well preserved offsets based on both 2D-orthophotos and 3D-views of the landscape. The results show that the UAV data provides centimeter resolution, allowing accurate mapping of past ruptures. We determine a co-seismic offset of 5.6 m for the last event south of Annanba. We also reconstruct cumulative offsets of 11±0.5 m, 22±1 m and 32±2 m. The horizontal offsets obtained suggest that last and penultimate events had similar slip amounts locally. The larger slip values deduced from the other offsets may also result from repeated 5-5.5 m co-seismic slip but more data is needed to confirm such a characteristic slip behavior. Clearly, UAV-based imagery shows great potential for high-resolution seismotectonic research and seismic hazard assessment.

  19. Mapping of traditional settlements by unmanned airborne vehicles towards architectural restoration

    NASA Astrophysics Data System (ADS)

    Partsinevelos, Panagiotis; Skoutelis, Nikolaos; Tripolitsiotis, Achilleas; Tsatsarounos, Stelios; Tsitonaki, Anna; Zervos, Panagiotis

    2015-06-01

    Conservation and restoration of traditional settlements are amongst the actions that international directives proclaim in order to protect our cultural heritage. Towards this end, a mandatory base step in all archaeological and historical practices includes the surveying and mapping of the study area. Often, new, unexplored or abandoned settlements are considered, where dense vegetation, damaged structures and ruins, incorporation of newer structures and renovation characteristics make the precise surveying procedure a labor intensive and time consuming procedure. Unmanned airborne vehicles (UAVs) have been effectively incorporated into several cultural heritage projects mainly for mapping archeological sites. However, the majority of relevant publications lack of quantitative evaluation of their results and when such a validation is provided it is rather a procedural error estimation readily available from the software used, without independent ground truth verification. In this study, a low-cost custom-built hexacopter prototype was employed to deliver accurate mapping of the traditional settlement of Kamariotis in east Crete, Greece. The case of Kamariotis settlement included highly dense urban structures with continuous building forms, curved walls and missing terraces, while wild vegetation made classic geodetic surveying unfeasible. The resulting maps were qualitatively compared against the ones derived using Google Earth and the Greek Cadastral Orthophoto Viewing platforms to evaluate their applicability for architectural mapping. Moreover, the overall precision of the photogrammetric procedure was compared against geodetic surveying.

  20. Small UAV-Acquired, High-resolution, Georeferenced Still Imagery

    SciTech Connect

    Ryan Hruska

    2005-09-01

    Currently, small Unmanned Aerial Vehicles (UAVs) are primarily used for capturing and down-linking real-time video. To date, their role as a low-cost airborne platform for capturing high-resolution, georeferenced still imagery has not been fully utilized. On-going work within the Unmanned Vehicle Systems Program at the Idaho National Laboratory (INL) is attempting to exploit this small UAV-acquired, still imagery potential. Initially, a UAV-based still imagery work flow model was developed that includes initial UAV mission planning, sensor selection, UAV/sensor integration, and imagery collection, processing, and analysis. Components to support each stage of the work flow are also being developed. Critical to use of acquired still imagery is the ability to detect changes between images of the same area over time. To enhance the analysts’ change detection ability, a UAV-specific, GIS-based change detection system called SADI or System for Analyzing Differences in Imagery is under development. This paper will discuss the associated challenges and approaches to collecting still imagery with small UAVs. Additionally, specific components of the developed work flow system will be described and graphically illustrated using varied examples of small UAV-acquired still imagery.

  1. Object-based detection of vehicles in airborne data

    NASA Astrophysics Data System (ADS)

    Schilling, Hendrik; Bulatov, Dimitri; Middelmann, Wolfgang

    2015-10-01

    Robust detection of vehicles in airborne data is a challenging task since a high variation in the object signatures - depending on data resolution - and often a small contrast between objects and background lead to high false classification rates and missed detections. Despite these facts, many applications require reliable results which can be obtained in a short time. In this paper, an object-based approach for vehicle detection in airborne laser scans (ALS) and photogrammetrically reconstructed 2.5D data is described. The focus of this paper lies on a robust object segmentation algorithm as well as the identification of features for a reliable separation between vehicles and background (all nonevehicle objects) on different scenes. The described method is based on three consecutive steps, namely, object segmentation, feature extraction and supervised classification. In the first step, the 2.5D data is segmented and possible targets are identified. The segmentation progress is based on the morphological top-hat filtering, which leaves areas that are smaller than a given filter size and higher (brighter) than their surroundings. The approach is chosen due to the low computational effort of this filter, which allows a fast computation even for large areas. The next step is feature extraction. Based on the initial segmentation, features for every identified object are extracted. In addition to frequently used features like height above ground, object area, or point distribution, more complex features like object planarity, entropy in the intensity image, and lineness measures are used. The last step contains classification of each object. For this purpose, a random forest classifier (RF) using the normalized features extracted in the previous step is chosen. RFs are suitable for high dimensional and nonlinear problems. In contrast to other approaches (e.g. maximum likelihood classifier), RFs achieves good results even with relatively small training samples.

  2. Land cover/use mapping using multi-band imageries captured by Cropcam Unmanned Aerial Vehicle Autopilot (UAV) over Penang Island, Malaysia

    NASA Astrophysics Data System (ADS)

    Fuyi, Tan; Boon Chun, Beh; Mat Jafri, Mohd Zubir; Hwee San, Lim; Abdullah, Khiruddin; Mohammad Tahrin, Norhaslinda

    2012-11-01

    The problem of difficulty in obtaining cloud-free scene at the Equatorial region from satellite platforms can be overcome by using airborne imagery. Airborne digital imagery has proved to be an effective tool for land cover studies. Airborne digital camera imageries were selected in this present study because of the airborne digital image provides higher spatial resolution data for mapping a small study area. The main objective of this study is to classify the RGB bands imageries taken from a low-altitude Cropcam UAV for land cover/use mapping over USM campus, penang Island, Malaysia. A conventional digital camera was used to capture images from an elevation of 320 meter on board on an UAV autopilot. This technique was cheaper and economical compared with other airborne studies. The artificial neural network (NN) and maximum likelihood classifier (MLC) were used to classify the digital imageries captured by using Cropcam UAV over USM campus, Penang Islands, Malaysia. The supervised classifier was chosen based on the highest overall accuracy (<80%) and Kappa statistic (<0.8). The classified land cover map was geometrically corrected to provide a geocoded map. The results produced by this study indicated that land cover features could be clearly identified and classified into a land cover map. This study indicates the use of a conventional digital camera as a sensor on board on an UAV autopilot can provide useful information for planning and development of a small area of coverage.

  3. Development of 3D electromagnetic modeling tools for airborne vehicles

    NASA Technical Reports Server (NTRS)

    Volakis, John L.

    1992-01-01

    The main goal of this report is to advance the development of methodologies for scattering by airborne composite vehicles. Although the primary focus continues to be the development of a general purpose computer code for analyzing the entire structure as a single unit, a number of other tasks are also being pursued in parallel with this effort. One of these tasks discussed within is on new finite element formulations and mesh termination schemes. The goal here is to decrease computation time while retaining accuracy and geometric adaptability.The second task focuses on the application of wavelets to electromagnetics. Wavelet transformations are shown to be able to reduce a full matrix to a band matrix, thereby reducing the solutions memory requirements. Included within this document are two separate papers on finite element formulations and wavelets.

  4. Using Unmanned Aerial Vehicle (UAV) for spatio-temporal monitoring of soil erosion and roughness in Chania, Crete, Greece

    NASA Astrophysics Data System (ADS)

    Alexakis, Dimitrios; Seiradakis, Kostas; Tsanis, Ioannis

    2016-04-01

    This article presents a remote sensing approach for spatio-temporal monitoring of both soil erosion and roughness using an Unmanned Aerial Vehicle (UAV). Soil erosion by water is commonly known as one of the main reasons for land degradation. Gully erosion causes considerable soil loss and soil degradation. Furthermore, quantification of soil roughness (irregularities of the soil surface due to soil texture) is important and affects surface storage and infiltration. Soil roughness is one of the most susceptible to variation in time and space characteristics and depends on different parameters such as cultivation practices and soil aggregation. A UAV equipped with a digital camera was employed to monitor soil in terms of erosion and roughness in two different study areas in Chania, Crete, Greece. The UAV followed predicted flight paths computed by the relevant flight planning software. The photogrammetric image processing enabled the development of sophisticated Digital Terrain Models (DTMs) and ortho-image mosaics with very high resolution on a sub-decimeter level. The DTMs were developed using photogrammetric processing of more than 500 images acquired with the UAV from different heights above the ground level. As the geomorphic formations can be observed from above using UAVs, shadowing effects do not generally occur and the generated point clouds have very homogeneous and high point densities. The DTMs generated from UAV were compared in terms of vertical absolute accuracies with a Global Navigation Satellite System (GNSS) survey. The developed data products were used for quantifying gully erosion and soil roughness in 3D as well as for the analysis of the surrounding areas. The significant elevation changes from multi-temporal UAV elevation data were used for estimating diachronically soil loss and sediment delivery without installing sediment traps. Concerning roughness, statistical indicators of surface elevation point measurements were estimated and various

  5. Does the Data Resolution/origin Matter? Satellite, Airborne and Uav Imagery to Tackle Plant Invasions

    NASA Astrophysics Data System (ADS)

    Müllerová, Jana; Brůna, Josef; Dvořák, Petr; Bartaloš, Tomáš; Vítková, Michaela

    2016-06-01

    Invasive plant species represent a serious threat to biodiversity and landscape as well as human health and socio-economy. To successfully fight plant invasions, new methods enabling fast and efficient monitoring, such as remote sensing, are needed. In an ongoing project, optical remote sensing (RS) data of different origin (satellite, aerial and UAV), spectral (panchromatic, multispectral and color), spatial (very high to medium) and temporal resolution, and various technical approaches (object-, pixelbased and combined) are tested to choose the best strategies for monitoring of four invasive plant species (giant hogweed, black locust, tree of heaven and exotic knotweeds). In our study, we address trade-offs between spectral, spatial and temporal resolutions required for balance between the precision of detection and economic feasibility. For the best results, it is necessary to choose best combination of spatial and spectral resolution and phenological stage of the plant in focus. For species forming distinct inflorescences such as giant hogweed iterative semi-automated object-oriented approach was successfully applied even for low spectral resolution data (if pixel size was sufficient) whereas for lower spatial resolution satellite imagery or less distinct species with complicated architecture such as knotweed, combination of pixel and object based approaches was used. High accuracies achieved for very high resolution data indicate the possible application of described methodology for monitoring invasions and their long-term dynamics elsewhere, making management measures comparably precise, fast and efficient. This knowledge serves as a basis for prediction, monitoring and prioritization of management targets.

  6. Application of Vehicle Dynamic Modeling in Uavs for Precise Determination of Exterior Orientation

    NASA Astrophysics Data System (ADS)

    Khaghani, M.; Skaloud, J.

    2016-06-01

    Advances in unmanned aerial vehicles (UAV) and especially micro aerial vehicle (MAV) technology together with increasing quality and decreasing price of imaging devices have resulted in growing use of MAVs in photogrammetry. The practicality of MAV mapping is seriously enhanced with the ability to determine parameters of exterior orientation (EO) with sufficient accuracy, in both absolute and relative senses (change of attitude between successive images). While differential carrier phase GNSS satisfies cm-level positioning accuracy, precise attitude determination is essential for both direct sensor orientation (DiSO) and integrated sensor orientation (ISO) in corridor mapping or in block configuration imaging over surfaces with low texture. Limited cost, size, and weight of MAVs represent limitations on quality of onboard navigation sensors and puts emphasis on exploiting full capacity of available resources. Typically short flying times (10-30 minutes) also limit the possibility of estimating and/or correcting factors such as sensor misalignment and poor attitude initialization of inertial navigation system (INS). This research aims at increasing the accuracy of attitude determination in both absolute and relative senses with no extra sensors onboard. In comparison to classical INS/GNSS setup, novel approach is presented here to integrated state estimation, in which vehicle dynamic model (VDM) is used as the main process model. Such system benefits from available information from autopilot and physical properties of the platform in enhancing performance of determination of trajectory and parameters of exterior orientation consequently. The navigation system employs a differential carrier phase GNSS receiver and a micro electro-mechanical system (MEMS) grade inertial measurement unit (IMU), together with MAV control input from autopilot. Monte-Carlo simulation has been performed on trajectories for typical corridor mapping and block imaging. Results reveal

  7. Lidar-equipped uav for building information modelling

    NASA Astrophysics Data System (ADS)

    Roca, D.; Armesto, J.; Lagüela, S.; Díaz-Vilariño, L.

    2014-06-01

    The trend to minimize electronic devices in the last decades accounts for Unmanned Airborne Vehicles (UAVs) as well as for sensor technologies and imaging devices, resulting in a strong revolution in the surveying and mapping industries. However, only within the last few years the LIDAR sensor technology has achieved sufficiently reduction in terms of size and weight to be considered for UAV platforms. This paper presents an innovative solution to capture point cloud data from a Lidar-equipped UAV and further perform the 3D modelling of the whole envelope of buildings in BIM format. A mini-UAV platform is used (weigh less than 5 kg and up to 1.5 kg of sensor payload), and data from two different acquisition methodologies is processed and compared with the aim at finding the optimal configuration for the generation of 3D models of buildings for energy studies

  8. Telesurgery via Unmanned Aerial Vehicle (UAV) with a field deployable surgical robot.

    PubMed

    Lum, Mitchell J H; Rosen, Jacob; King, Hawkeye; Friedman, Diana C W; Donlin, Gina; Sankaranarayanan, Ganesh; Harnett, Brett; Huffman, Lynn; Doarn, Charles; Broderick, Timothy; Hannaford, Blake

    2007-01-01

    Robotically assisted surgery stands to further revolutionize the medical field and provide patients with more effective healthcare. Most robotically assisted surgeries are teleoperated from the surgeon console to the patient where both ends of the system are located in the operating room. The challenge of surgical teleoperation across a long distance was already demonstrated through a wired communication network in 2001. New development has shifted towards deploying a surgical robot system in mobile settings and/or extreme environments such as the battlefield or natural disaster areas with surgeons operating wirelessly. As a collaborator in the HAPs/MRT (High Altitude Platform/Mobile Robotic Telesurgery) project, The University of Washington surgical robot was deployed in the desert of Simi Valley, CA for telesurgery experiments on an inanimate model via wireless communication through an Unmanned Aerial Vehicle (UAV). The surgical tasks were performed telerobotically with a maximum time delay between the surgeon's console (master) and the surgical robot (slave) of 20 ms for the robotic control signals and 200 ms for the video stream. This was our first experiment in the area of Mobile Robotic Telesurgery (MRT). The creation and initial testing of a deployable surgical robot system will facilitate growth in this area eventually leading to future systems saving human lives in disaster areas, on the battlefield or in other remote environments.

  9. Unmanned Aerial Vehicles (UAVs) and Artificial Intelligence Revolutionizing Wildlife Monitoring and Conservation.

    PubMed

    Gonzalez, Luis F; Montes, Glen A; Puig, Eduard; Johnson, Sandra; Mengersen, Kerrie; Gaston, Kevin J

    2016-01-14

    Surveying threatened and invasive species to obtain accurate population estimates is an important but challenging task that requires a considerable investment in time and resources. Estimates using existing ground-based monitoring techniques, such as camera traps and surveys performed on foot, are known to be resource intensive, potentially inaccurate and imprecise, and difficult to validate. Recent developments in unmanned aerial vehicles (UAV), artificial intelligence and miniaturized thermal imaging systems represent a new opportunity for wildlife experts to inexpensively survey relatively large areas. The system presented in this paper includes thermal image acquisition as well as a video processing pipeline to perform object detection, classification and tracking of wildlife in forest or open areas. The system is tested on thermal video data from ground based and test flight footage, and is found to be able to detect all the target wildlife located in the surveyed area. The system is flexible in that the user can readily define the types of objects to classify and the object characteristics that should be considered during classification.

  10. Unmanned Aerial Vehicles (UAVs) and Artificial Intelligence Revolutionizing Wildlife Monitoring and Conservation.

    PubMed

    Gonzalez, Luis F; Montes, Glen A; Puig, Eduard; Johnson, Sandra; Mengersen, Kerrie; Gaston, Kevin J

    2015-01-01

    Surveying threatened and invasive species to obtain accurate population estimates is an important but challenging task that requires a considerable investment in time and resources. Estimates using existing ground-based monitoring techniques, such as camera traps and surveys performed on foot, are known to be resource intensive, potentially inaccurate and imprecise, and difficult to validate. Recent developments in unmanned aerial vehicles (UAV), artificial intelligence and miniaturized thermal imaging systems represent a new opportunity for wildlife experts to inexpensively survey relatively large areas. The system presented in this paper includes thermal image acquisition as well as a video processing pipeline to perform object detection, classification and tracking of wildlife in forest or open areas. The system is tested on thermal video data from ground based and test flight footage, and is found to be able to detect all the target wildlife located in the surveyed area. The system is flexible in that the user can readily define the types of objects to classify and the object characteristics that should be considered during classification. PMID:26784196

  11. Small unmanned aerial vehicles (micro-UAVs, drones) in plant ecology1

    PubMed Central

    Cruzan, Mitchell B.; Weinstein, Ben G.; Grasty, Monica R.; Kohrn, Brendan F.; Hendrickson, Elizabeth C.; Arredondo, Tina M.; Thompson, Pamela G.

    2016-01-01

    Premise of the study: Low-elevation surveys with small aerial drones (micro–unmanned aerial vehicles [UAVs]) may be used for a wide variety of applications in plant ecology, including mapping vegetation over small- to medium-sized regions. We provide an overview of methods and procedures for conducting surveys and illustrate some of these applications. Methods: Aerial images were obtained by flying a small drone along transects over the area of interest. Images were used to create a composite image (orthomosaic) and a digital surface model (DSM). Vegetation classification was conducted manually and using an automated routine. Coverage of an individual species was estimated from aerial images. Results: We created a vegetation map for the entire region from the orthomosaic and DSM, and mapped the density of one species. Comparison of our manual and automated habitat classification confirmed that our mapping methods were accurate. A species with high contrast to the background matrix allowed adequate estimate of its coverage. Discussion: The example surveys demonstrate that small aerial drones are capable of gathering large amounts of information on the distribution of vegetation and individual species with minimal impact to sensitive habitats. Low-elevation aerial surveys have potential for a wide range of applications in plant ecology. PMID:27672518

  12. Small unmanned aerial vehicles (micro-UAVs, drones) in plant ecology1

    PubMed Central

    Cruzan, Mitchell B.; Weinstein, Ben G.; Grasty, Monica R.; Kohrn, Brendan F.; Hendrickson, Elizabeth C.; Arredondo, Tina M.; Thompson, Pamela G.

    2016-01-01

    Premise of the study: Low-elevation surveys with small aerial drones (micro–unmanned aerial vehicles [UAVs]) may be used for a wide variety of applications in plant ecology, including mapping vegetation over small- to medium-sized regions. We provide an overview of methods and procedures for conducting surveys and illustrate some of these applications. Methods: Aerial images were obtained by flying a small drone along transects over the area of interest. Images were used to create a composite image (orthomosaic) and a digital surface model (DSM). Vegetation classification was conducted manually and using an automated routine. Coverage of an individual species was estimated from aerial images. Results: We created a vegetation map for the entire region from the orthomosaic and DSM, and mapped the density of one species. Comparison of our manual and automated habitat classification confirmed that our mapping methods were accurate. A species with high contrast to the background matrix allowed adequate estimate of its coverage. Discussion: The example surveys demonstrate that small aerial drones are capable of gathering large amounts of information on the distribution of vegetation and individual species with minimal impact to sensitive habitats. Low-elevation aerial surveys have potential for a wide range of applications in plant ecology.

  13. Unmanned Aerial Vehicles (UAVs) and Artificial Intelligence Revolutionizing Wildlife Monitoring and Conservation

    PubMed Central

    Gonzalez, Luis F.; Montes, Glen A.; Puig, Eduard; Johnson, Sandra; Mengersen, Kerrie; Gaston, Kevin J.

    2016-01-01

    Surveying threatened and invasive species to obtain accurate population estimates is an important but challenging task that requires a considerable investment in time and resources. Estimates using existing ground-based monitoring techniques, such as camera traps and surveys performed on foot, are known to be resource intensive, potentially inaccurate and imprecise, and difficult to validate. Recent developments in unmanned aerial vehicles (UAV), artificial intelligence and miniaturized thermal imaging systems represent a new opportunity for wildlife experts to inexpensively survey relatively large areas. The system presented in this paper includes thermal image acquisition as well as a video processing pipeline to perform object detection, classification and tracking of wildlife in forest or open areas. The system is tested on thermal video data from ground based and test flight footage, and is found to be able to detect all the target wildlife located in the surveyed area. The system is flexible in that the user can readily define the types of objects to classify and the object characteristics that should be considered during classification. PMID:26784196

  14. Unmanned Aerial Vehicle (UAV) Dynamic-Tracking Directional Wireless Antennas for Low Powered Applications that Require Reliable Extended Range Operations in Time Critical Scenarios

    SciTech Connect

    Scott G. Bauer; Matthew O. Anderson; James R. Hanneman

    2005-10-01

    The proven value of DOD Unmanned Aerial Vehicles (UAVs) will ultimately transition to National and Homeland Security missions that require real-time aerial surveillance, situation awareness, force protection, and sensor placement. Public services first responders who routinely risk personal safety to assess and report a situation for emergency actions will likely be the first to benefit from these new unmanned technologies. ‘Packable’ or ‘Portable’ small class UAVs will be particularly useful to the first responder. They require the least amount of training, no fixed infrastructure, and are capable of being launched and recovered from the point of emergency. All UAVs require wireless communication technologies for real- time applications. Typically on a small UAV, a low bandwidth telemetry link is required for command and control (C2), and systems health monitoring. If the UAV is equipped with a real-time Electro-Optical or Infrared (EO/Ir) video camera payload, a dedicated high bandwidth analog/digital link is usually required for reliable high-resolution imagery. In most cases, both the wireless telemetry and real-time video links will be integrated into the UAV with unity gain omni-directional antennas. With limited on-board power and payload capacity, a small UAV will be limited with the amount of radio-frequency (RF) energy it transmits to the users. Therefore, ‘packable’ and ‘portable’ UAVs will have limited useful operational ranges for first responders. This paper will discuss the limitations of small UAV wireless communications. The discussion will present an approach of utilizing a dynamic ground based real-time tracking high gain directional antenna to provide extend range stand-off operation, potential RF channel reuse, and assured telemetry and data communications from low-powered UAV deployed wireless assets.

  15. Wildlife Multispecies Remote Sensing Using Visible and Thermal Infrared Imagery Acquired from AN Unmanned Aerial Vehicle (uav)

    NASA Astrophysics Data System (ADS)

    Chrétien, L.-P.; Théau, J.; Ménard, P.

    2015-08-01

    Wildlife aerial surveys require time and significant resources. Multispecies detection could reduce costs to a single census for species that coexist spatially. Traditional methods are demanding for observers in terms of concentration and are not adapted to multispecies censuses. The processing of multispectral aerial imagery acquired from an unmanned aerial vehicle (UAV) represents a potential solution for multispecies detection. The method used in this study is based on a multicriteria object-based image analysis applied on visible and thermal infrared imagery acquired from a UAV. This project aimed to detect American bison, fallow deer, gray wolves, and elks located in separate enclosures with a known number of individuals. Results showed that all bison and elks were detected without errors, while for deer and wolves, 0-2 individuals per flight line were mistaken with ground elements or undetected. This approach also detected simultaneously and separately the four targeted species even in the presence of other untargeted ones. These results confirm the potential of multispectral imagery acquired from UAV for wildlife census. Its operational application remains limited to small areas related to the current regulations and available technology. Standardization of the workflow will help to reduce time and expertise requirements for such technology.

  16. The payload bay in the nose of NASA's Altair unmanned aerial vehicle (UAV) will be able to carry up

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The payload bay in the nose of NASA's Altair unmanned aerial vehicle (UAV), shown here during final construction at General Atomics Aeronautical Systems, Inc., (GA-ASI) facility at Adelanto, Calif., will be able to carry up to 700 lbs. of sensors, imaging equipment and other instruments for Earth science missions. General Atomics Aeronautical Systems, Inc., is developing the Altair version of its Predator B unmanned reconnaissance aircraft under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project. NASA plans to use the Altair as a technology demonstrator to validate a variety of command and control technologies for UAVs, as well as demonstrate the capability to perform a variety of Earth science missions. The Altair is designed to carry an 700-lb. payload of scientific instruments and imaging equipment for as long as 32 hours at up to 52,000 feet altitude. Eleven-foot extensions have been added to each wing, giving the Altair an overall wingspan of 86 feet with an aspect ratio of 23. It is powered by a 700-hp. rear-mounted TPE-331-10 turboprop engine, driving a three-blade propeller. Altair is scheduled to begin flight tests in the fourth quarter of 2002, and be acquired by NASA following successful completion of basic airworthiness tests in early 2003 for evaluation of over-the-horizon control, detect, see and avoid and other technologies required to allow UAVs to operate safely with other aircraft in the national airspace.

  17. Technical Note: Advances in flash flood monitoring using unmanned aerial vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    Perks, Matthew T.; Russell, Andrew J.; Large, Andrew R. G.

    2016-10-01

    Unmanned aerial vehicles (UAVs) have the potential to capture information about the earth's surface in dangerous and previously inaccessible locations. Through image acquisition of flash flood events and subsequent object-based analysis, highly dynamic and oft-immeasurable hydraulic phenomena may be quantified at previously unattainable spatial and temporal resolutions. The potential for this approach to provide valuable information about the hydraulic conditions present during dynamic, high-energy flash floods has until now not been explored. In this paper we adopt a novel approach, utilizing the Kande-Lucas-Tomasi (KLT) algorithm to track features present on the water surface which are related to the free-surface velocity. Following the successful tracking of features, a method analogous to the vector correction method has enabled accurate geometric rectification of velocity vectors. Uncertainties associated with the rectification process induced by unsteady camera movements are subsequently explored. Geo-registration errors are relatively stable and occur as a result of persistent residual distortion effects following image correction. The apparent ground movement of immobile control points between measurement intervals ranges from 0.05 to 0.13 m. The application of this approach to assess the hydraulic conditions present in the Alyth Burn, Scotland, during a 1 : 200 year flash flood resulted in the generation of an average 4.2 at a rate of 508 measurements s-1. Analysis of these vectors provides a rare insight into the complexity of channel-overbank interactions during flash floods. The uncertainty attached to the calculated velocities is relatively low, with a spatial average across the area of ±0.15 m s-1. Little difference is observed in the uncertainty attached to out-of-bank velocities (±0.15 m s-1), and within-channel velocities (±0.16 m s-1), illustrating the consistency of the approach.

  18. Looking Inward to the Use of Unmanned Aerial Vehicle (UAV) for Rice Production Assessment in Indonesia

    NASA Astrophysics Data System (ADS)

    Komaladara, A. A. S. P.; Ambarawati, I. G. A. A.; Wijaya, I. M. A. S.; Hongo, C.; Mirah Adi, A. A. A.

    2015-12-01

    Rice is the main source of carbohydrate for most Indonesians. Rice production has been very dynamic due to improved infrastructure, research and development, and better farm management. However, rice production is susceptible to loss caused by drought, pest and disease attack and climate change. With the growing concern on sustainable and self-reliance food production in the country, there is an urgency to encourage research and efforts to increase rice productivity. Attempts to provide spatial distribution of rice fields on high resolution optical remote sensing data have been employed to some extent, however this technology could be costly. The use of UAV has been introduced to estimate damage ratio in rice crop recently in Indonesia. This technology is one of the ways to estimate rice production quicker, cost-saving and before harvesting time. This study aims to analyze spatio temporal and damage ratio of rice crop using UAV in Indonesia. The study empirically presents the use of UAV (Phantom 2 Vision +) on rice fields to the soil condition and development of management zone map in Bali as an example. The study concludes that the use of UAV allows researchers to pin point characteristics of crop and land in a specific area of a farm. This will then allow researchers to assist farmers in implementing specific and appropriate solutions to production issues. Key words: UAV, rice production, damage ratio

  19. Remote Sensing of Arctic Environmental Conditions and Critical Infrastructure using Infra-Red (IR) Cameras and Unmanned Air Vehicles (UAVs)

    NASA Astrophysics Data System (ADS)

    Hatfield, M. C.; Webley, P.; Saiet, E., II

    2014-12-01

    Remote Sensing of Arctic Environmental Conditions and Critical Infrastructure using Infra-Red (IR) Cameras and Unmanned Air Vehicles (UAVs) Numerous scientific and logistical applications exist in Alaska and other arctic regions requiring analysis of expansive, remote areas in the near infrared (NIR) and thermal infrared (TIR) bands. These include characterization of wild land fire plumes and volcanic ejecta, detailed mapping of lava flows, and inspection of lengthy segments of critical infrastructure, such as the Alaska pipeline and railroad system. Obtaining timely, repeatable, calibrated measurements of these extensive features and infrastructure networks requires localized, taskable assets such as UAVs. The Alaska Center for Unmanned Aircraft Systems Integration (ACUASI) provides practical solutions to these problem sets by pairing various IR sensors with a combination of fixed-wing and multi-rotor air vehicles. Fixed-wing assets, such as the Insitu ScanEagle, offer long reach and extended duration capabilities to quickly access remote locations and provide enduring surveillance of the target of interest. Rotary-wing assets, such as the Aeryon Scout or the ACUASI-built Ptarmigan hexcopter, provide a precision capability for detailed horizontal mapping or vertical stratification of atmospheric phenomena. When included with other ground capabilities, we will show how they can assist in decision support and hazard assessment as well as giving those in emergency management a new ability to increase knowledge of the event at hand while reducing the risk to all involved. Here, in this presentation, we illustrate how UAV's can provide the ideal tool to map and analyze the hazardous events and critical infrastructure under extreme environmental conditions.

  20. UAV field demonstration of social media enabled tactical data link

    NASA Astrophysics Data System (ADS)

    Olson, Christopher C.; Xu, Da; Martin, Sean R.; Castelli, Jonathan C.; Newman, Andrew J.

    2015-05-01

    This paper addresses the problem of enabling Command and Control (C2) and data exfiltration functions for missions using small, unmanned, airborne surveillance and reconnaissance platforms. The authors demonstrated the feasibility of using existing commercial wireless networks as the data transmission infrastructure to support Unmanned Aerial Vehicle (UAV) autonomy functions such as transmission of commands, imagery, metadata, and multi-vehicle coordination messages. The authors developed and integrated a C2 Android application for ground users with a common smart phone, a C2 and data exfiltration Android application deployed on-board the UAVs, and a web server with database to disseminate the collected data to distributed users using standard web browsers. The authors performed a mission-relevant field test and demonstration in which operators commanded a UAV from an Android device to search and loiter; and remote users viewed imagery, video, and metadata via web server to identify and track a vehicle on the ground. Social media served as the tactical data link for all command messages, images, videos, and metadata during the field demonstration. Imagery, video, and metadata were transmitted from the UAV to the web server via multiple Twitter, Flickr, Facebook, YouTube, and similar media accounts. The web server reassembled images and video with corresponding metadata for distributed users. The UAV autopilot communicated with the on-board Android device via on-board Bluetooth network.

  1. MaNIAC-UAV - a methodology for automatic pavement defects detection using images obtained by Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Henrique Castelo Branco, Luiz; César Lima Segantine, Paulo

    2015-09-01

    Intelligent Transportation Systems - ITS is a set of integrated technologies (Remote Sensing, Image Processing, Communications Systems and others) that aim to offer services and advanced traffic management for the several transportation modes (road, air and rail). Collect data on the characteristics and conditions of the road surface and keep them update is an important and difficult task that needs to be currently managed in order to reduce accidents and vehicle maintenance costs. Nowadays several roads and highways are paved, but usually there is insufficient updated data about current condition and status. There are different types of pavement defects on the roads and to keep them in good condition they should be constantly monitored and maintained according to pavement management strategy. This paper presents a methodology to obtain, automatically, information about the conditions of the highway asphalt pavement. Data collection was done through remote sensing using an UAV (Unmanned Aerial Vehicle) and the image processing and pattern recognition techniques through Geographic Information System.

  2. Development of 3D electromagnetic modeling tools for airborne vehicles

    NASA Technical Reports Server (NTRS)

    Volakis, John L.

    1992-01-01

    The main goal of this project is to develop methodologies for scattering by airborne composite vehicles. Although our primary focus continues to be the development of a general purpose code for analyzing the entire structure as a single unit, a number of other tasks are also pursued in parallel with this effort. These tasks are important in testing the overall approach and in developing suitable models for materials coatings, junctions and, more generally, in assessing the effectiveness of the various parts comprising the final code. Here, we briefly discuss our progress on the five different tasks which were pursued during this period. Our progress on each of these tasks is described in the detailed reports (listed at the end of this report) and the memoranda included. The first task described below is, of course, the core of this project and deals with the development of the overall code. Undoubtedly, it is the outcome of the research which was funded by NASA-Ames and the Navy over the past three years. During this year we developed the first finite element code for scattering by structures of arbitrary shape and composition. The code employs a new absorbing boundary condition which allows termination of the finite element mesh only 0.3 lambda from the outer surface of the target. This leads to a remarkable reduction of the mesh size and is a unique feature of the code. Other unique features of this code include capabilities to model resistive sheets, impedance sheets and anisotropic materials. This last capability is the latest feature of the code and is still under development. The code has been extensively validated for a number of composite geometries and some examples are given. The validation of the code is still in progress for anisotropic and larger non-metallic geometries and cavities. The developed finite element code is based on a Galerkin's formulation and employs edge-based tetrahedral elements for discretizing the dielectric sections and the region

  3. Observing changes at Santiaguito Volcano, Guatemala with an Unmanned Aerial Vehicle (UAV)

    NASA Astrophysics Data System (ADS)

    von Aulock, Felix W.; Lavallée, Yan; Hornby, Adrian J.; Lamb, Oliver D.; Andrews, Benjamin J.; Kendrick, Jackie E.

    2016-04-01

    Santiaguito Volcano (Guatemala) is one of the most active volcanoes in Central America, producing several ash venting explosions per day for almost 100 years. Lahars, lava flows and dome and flank collapses that produce major pyroclastic density currents also present a major hazard to nearby farms and communities. Optical observations of both the vent as well as the lava flow fronts can provide scientists and local monitoring staff with important information on the current state of volcanic activity and hazard. Due to the strong activity, and difficult terrain, unmanned aerial vehicles can help to provide valuable data on the activities of the volcano at a safe distance. We collected a series of images and video footage of A.) The active vent of Caliente and B.) The flow front of the active lava flow and its associated lahar channels, both in May 2015 and in December 2015- January 2016. Images of the crater and the lava flows were used for the reconstruction of 3D terrain models using structure-from-motion. These were supported by still frames from the video recording. Video footage of the summit crater (during two separate ash venting episodes) and the lava flow fronts indicate the following differences in activity during those two field campaigns: A.) - A new breach opened on the east side of the crater rim, possibly during the collapse in November 2015. - The active lava dome is now almost completely covered with ash, only leaving the largest blocks and faults exposed in times without gas venting - A recorded explosive event in December 2015 initiates at subparallel linear faults near the centre of the dome, rather than arcuate or ring faults, with a later, separate, and more ash-laden burst occurring from an off-centre fracture, however, other explosions during the observation period were seen to persist along the ring fault system observed on the lava dome since at least 2007 - suggesting a diversification of explosive activity. B.) - The lava flow fronts did

  4. Spatial distribution of water stress and evapotranspiration estimates using an unmanned aerial vehicle (UAV)

    NASA Astrophysics Data System (ADS)

    Rauneker, P.; Lischeid, G.

    2012-04-01

    The estimation of spatial distribution of evapotranspiration poses a particular challenge in quantitative hydrology. Conventional methods provide punctual measurements of evapotranspiration rates which may be transformed into aggregated mean values by extrapolation or the application of empirical models. The influence of spatial structures (heterogeneity of the landscape) in relevant small spatial scales is captured insufficiently by these methods. Modern optical remote sensors aboard an unmanned aerial vehicle (UAV) provide the basis for the generation of high spatial resolution data. Spectral data in the optical, near infrared and thermal infrared domain will be used as input into a surface energy balance (SEB) model to produce evapotranspiration maps. The spectral properties of vegetation are of particular importance for the calculation, since plants are the link between soil and atmosphere and thus have major impact on evapotranspiration rates of land surfaces. First estimates of plant status and indicators of transpiration behavior will be obtained by applying and combining water stress parameters of different wavelengths. As opposed to satellite data, time-series of self-determined spatial and temporal resolution may be created by varying flight altitude and turnaround times. Thus it is possible to analyze the influence of landscape structures, as well as the chronological development of the observed parameters. Located at the interface between hydrology and remote sensing this work utilizes an innovative remote sensing platform to gain distributed spectral information. This information will be used to visualize evapotranspiration patterns in hydrological heterogeneous areas. Particular attention will be paid to the analysis of transition zones of varying water supply and under the influence of selected environmental parameters (e.g. soil moisture, depth of GW-table). To reach that goal it is essential to generate a robust processing chain, involving all

  5. Long-term monitoring of a large landslide by using an Unmanned Aerial Vehicle (UAV)

    NASA Astrophysics Data System (ADS)

    Lindner, Gerald; Schraml, Klaus; Mansberger, Reinfried; Hübl, Johannes

    2015-04-01

    Currently UAVs become more and more important in various scientific areas, including forestry, precision farming, archaeology and hydrology. Using these drones in natural hazards research enables a completely new level of data acquisition being flexible of site, invariant in time, cost-efficient and enabling arbitrary spatial resolution. In this study, a rotary-wing Mini-UAV carrying a DSLR camera was used to acquire time series of overlapping aerial images. These photographs were taken as input to extract Digital Surface Models (DSM) as well as orthophotos in the area of interest. The "Pechgraben" area in Upper Austria has a catchment area of approximately 2 km². Geology is mainly dominated by limestone and sandstone. Caused by heavy rainfalls in the late spring of 2013, an area of about 70 ha began to move towards the village in the valley. In addition to the urgent measures, the slow-moving landslide was monitored approximately every month over a time period of more than 18 months. A detailed documentation of the change process was the result. Moving velocities and height differences were quantified and validated using a dense network of Ground Control Points (GCP). For further analysis, 14 image flights with a total amount of 10.000 photographs were performed to create multi-temporal geodata in in sub-decimeter-resolution for two depicted areas of the landslide. Using a UAV for this application proved to be an excellent choice, as it allows short repetition times, low flying heights and high spatial resolution. Furthermore, the UAV acts almost weather independently as well as highly autonomously. High-quality results can be expected within a few hours after the photo flight. The UAV system performs very well in an alpine environment. Time series of the assessed geodata detect changes in topography and provide a long-term documentation of the measures taken in order to stop the landslide and to prevent infrastructure from damage.

  6. Parallax visualization of UAV FMV and WAMI imagery

    NASA Astrophysics Data System (ADS)

    Mayhew, Christopher A.; Mayhew, Craig M.

    2012-06-01

    The US Military is increasingly relying on the use of unmanned aerial vehicles (UAV) for intelligence, surveillance, and reconnaissance (ISR) missions. Complex arrays of Full-Motion Video (FMV), Wide-Area Motion Imaging (WAMI) and Wide Area Airborne Surveillance (WAAS) technologies are being deployed on UAV platforms for ISR applications. Nevertheless, these systems are only as effective as the Image Analyst's (IA) ability to extract relevant information from the data. A variety of tools assist in the analysis of imagery captured with UAV sensors. However, until now, none has been developed to extract and visualize parallax three-dimensional information. Parallax Visualization (PV) is a technique that produces a near-three-dimensional visual response to standard UAV imagery. The overlapping nature of UAV imagery lends itself to parallax visualization. Parallax differences can be obtained by selecting frames that differ in time and, therefore, points of view of the area of interest. PV is accomplished using software tools to critically align a common point in two views while alternately displaying both views in a square-wave manner. Humans produce an autostereoscopic response to critically aligned parallax information presented alternately on a standard unaided display at frequencies between 3 and 6 Hz. This simple technique allows for the exploitation of spatial and temporal differences in image sequences to enhance depth, size, and spatial relationships of objects in areas of interest. PV of UAV imagery has been successfully performed in several US Military exercises over the last two years.

  7. Using Unmanned Aerial Vehicle (UAV) Imagery to Investigate Surface Displacements and Surface Features of the Super-Sauze Earthflow (France)

    NASA Astrophysics Data System (ADS)

    James, M. R.; Tizzard, S.; Niethammer, U.

    2014-12-01

    We present the result of using imagery collected with a small rotary wing UAV (unmanned aerial vehicle) to investigate surface displacements and fissures on the Super-Sauze earthflow (France); a slow moving earthflow with the potential to develop into rapid and highly destructive mud flows. UAV imagery acquired in October 2009 was processed using a structure-from-motion and multi-view stereo (SfM-MVS) approach in PhotoScan software. Identification of ~200 ground control points throughout the image set was facilitated by automated image matching in SfM_georef software[1] and the data incorporated into PhotoScan for network optimisation and georeferencing. The completed 2009 model enabled an ~5 cm spatial resolution orthoimage to be generated with an expected accuracy (based on residuals on control) of ~0.3 m. This was supported by comparison to a previously created 2008 model, which gave standard deviations on tie points (located on stationary terrain) of 0.27 m and 0.43 m in Easting and Northing respectively. The high resolution of the orthoimage allowed an investigation into surface displacements and geomorphology of surface features (compared to the 2008 model). The results have produced a comprehensive surface displacement map of the Super-Sauze earthflow, as well as highlighting interesting variations in fissure geomorphology and density between the 2008 and 2009 models. This study underscored the capability for UAV imagery and SfM-MVS to generate highly detailed orthographic imagery and DEMs with a low cost approach that offers significant potential for landslide hazard assessments. [1] http://www.lancaster.ac.uk/staff/jamesm/software/sfm_georef.htm

  8. Height Gradient Approach for Occlusion Detection in Uav Imagery

    NASA Astrophysics Data System (ADS)

    Oliveira, H. C.; Habib, A. F.; Dal Poz, A. P.; Galo, M.

    2015-08-01

    The use of Unmanned Aerial Vehicle (UAV) significantly increased in the last years. It is used for several different applications, such as mapping, publicity, security, natural disasters assistance, environmental monitoring, 3D building model generation, cadastral survey, etc. The imagery obtained by this kind of system has a great potential. To use these images in true orthophoto generation projects related to urban scenes or areas where buildings are present, it is important to consider the occlusion caused by surface height variation, platform attitude, and perspective projection. Occlusions in UAV imagery are usually larger than in conventional airborne dataset due to the low-altitude and excessive change in orientation due to the low-weight and wind effects during the flight mission. Therefore, this paper presents a method for occlusion detection together with some obtained results for images acquired by a UAV platform. The proposed method shows potential in occlusion detection and true orthophoto generation.

  9. Systematic observations of Volcán Turrialba, Costa Rica, with small unmanned aircraft and aerostats (UAVs): the Costa Rican Airborne Research and Technology Applications (CARTA) missions

    NASA Astrophysics Data System (ADS)

    Pieri, D. C.; Diaz, J. A.; Bland, G.; Fladeland, M. M.; Abtahi, A.; Alan, A., Jr.; Alegria, O.; Azofeifa, S.; Berthold, R.; Corrales, E.; Fuerstenau, S.; Gerardi, J.; Herlth, D.; Hickman, G.; Hunter, G.; Linick, J.; Madrigal, Y.; Makel, D.; Miles, T.; Realmuto, V. J.; Storms, B.; Vogel, A.; Kolyer, R.; Weber, K.

    2014-12-01

    For several years, the University of Costa Rica, NASA Centers (e.g., JPL, ARC, GSFC/WFF, GRC) & NASA contractors-partners have made regular in situ measurements of aerosols & gases at Turrialba Volcano in Costa Rica, with aerostats (e.g., tethered balloons & kites), & free-flying fixed wing UAVs (e.g., Dragon Eye, Vector Wing 100, DELTA 150), at altitudes up to 12.5Kft ASL within 5km of the summit. Onboard instruments included gas detectors (e.g., SO2, CO2), visible & thermal IR cameras, air samplers, temperature pressure & humidity sensors, particle counters, & a nephelometer. Deployments are timed to support bimonthly overflights of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) onboard the NASA Terra satellite (26 deployments to date). In situ observations of dilute plume SO2 concentrations (~1-20ppmv), plume dimensions, and associated temperature, pressure, & humidity profiles, validate detailed radiative transfer-based SO2 retrievals, as well as archive-wide ASTER band-ratio SO2 algorithms. Our recent UAV-based CO2 observations confirm high concentrations (e.g., ~3000ppmv max at summit jet), with 1000-1500ppmv flank values, and essentially global background CO2 levels (400ppmv) over distal surroundings. Transient Turrialba He detections (up to 20ppmv) were obtained with a small (~10kg) airborne mass spectrometer on a light aircraft—a UAV version (~3kg) will deploy there soon on the UCR DELTA 500. Thus, these platforms, though small (most payloads <500gm), can perform valuable systematic measurements of potential eruption hazards, as well as of volcano processes. Because they are economical, flexible, and effective, such platforms promise unprecedented capabilities for researchers and responders throughout Central and South America, undertaking volcanic data acquisitions uniquely suited to such small aircraft in close proximity to known hazards, or that were previously only available using full-sized manned aircraft. This work was

  10. High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology.

    PubMed

    Torres-Sánchez, Jorge; López-Granados, Francisca; Serrano, Nicolás; Arquero, Octavio; Peña, José M

    2015-01-01

    The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications.

  11. Quantifying efficacy and limits of unmanned aerial vehicle (UAV) technology for weed seedling detection as affected by sensor resolution.

    PubMed

    Peña, José M; Torres-Sánchez, Jorge; Serrano-Pérez, Angélica; de Castro, Ana I; López-Granados, Francisca

    2015-03-06

    In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera), spatial (flight altitude) and temporal (the date of the study) resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2), when plants had 5-6 true leaves, had the highest weed detection accuracy (up to 91%). At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing) because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations.

  12. Quantifying efficacy and limits of unmanned aerial vehicle (UAV) technology for weed seedling detection as affected by sensor resolution.

    PubMed

    Peña, José M; Torres-Sánchez, Jorge; Serrano-Pérez, Angélica; de Castro, Ana I; López-Granados, Francisca

    2015-01-01

    In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera), spatial (flight altitude) and temporal (the date of the study) resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2), when plants had 5-6 true leaves, had the highest weed detection accuracy (up to 91%). At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing) because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations. PMID:25756867

  13. High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology.

    PubMed

    Torres-Sánchez, Jorge; López-Granados, Francisca; Serrano, Nicolás; Arquero, Octavio; Peña, José M

    2015-01-01

    The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications. PMID:26107174

  14. High-Throughput 3-D Monitoring of Agricultural-Tree Plantations with Unmanned Aerial Vehicle (UAV) Technology

    PubMed Central

    Torres-Sánchez, Jorge; López-Granados, Francisca; Serrano, Nicolás; Arquero, Octavio; Peña, José M.

    2015-01-01

    The geometric features of agricultural trees such as canopy area, tree height and crown volume provide useful information about plantation status and crop production. However, these variables are mostly estimated after a time-consuming and hard field work and applying equations that treat the trees as geometric solids, which produce inconsistent results. As an alternative, this work presents an innovative procedure for computing the 3-dimensional geometric features of individual trees and tree-rows by applying two consecutive phases: 1) generation of Digital Surface Models with Unmanned Aerial Vehicle (UAV) technology and 2) use of object-based image analysis techniques. Our UAV-based procedure produced successful results both in single-tree and in tree-row plantations, reporting up to 97% accuracy on area quantification and minimal deviations compared to in-field estimations of tree heights and crown volumes. The maps generated could be used to understand the linkages between tree grown and field-related factors or to optimize crop management operations in the context of precision agriculture with relevant agro-environmental implications. PMID:26107174

  15. Quantifying Efficacy and Limits of Unmanned Aerial Vehicle (UAV) Technology for Weed Seedling Detection as Affected by Sensor Resolution

    PubMed Central

    Peña, José M.; Torres-Sánchez, Jorge; Serrano-Pérez, Angélica; de Castro, Ana I.; López-Granados, Francisca

    2015-01-01

    In order to optimize the application of herbicides in weed-crop systems, accurate and timely weed maps of the crop-field are required. In this context, this investigation quantified the efficacy and limitations of remote images collected with an unmanned aerial vehicle (UAV) for early detection of weed seedlings. The ability to discriminate weeds was significantly affected by the imagery spectral (type of camera), spatial (flight altitude) and temporal (the date of the study) resolutions. The colour-infrared images captured at 40 m and 50 days after sowing (date 2), when plants had 5–6 true leaves, had the highest weed detection accuracy (up to 91%). At this flight altitude, the images captured before date 2 had slightly better results than the images captured later. However, this trend changed in the visible-light images captured at 60 m and higher, which had notably better results on date 3 (57 days after sowing) because of the larger size of the weed plants. Our results showed the requirements on spectral and spatial resolutions needed to generate a suitable weed map early in the growing season, as well as the best moment for the UAV image acquisition, with the ultimate objective of applying site-specific weed management operations. PMID:25756867

  16. Airborne Wireless Optical Communication System in Low Altitude Using an Unmanned Aerial Vehicle and LEDs

    NASA Astrophysics Data System (ADS)

    Kong, Meiwei; Tong, Zheng; Yu, Xiangyu; Song, Yuhang; Lin, Aobo; Xu, Jing

    2016-02-01

    In this paper, we demonstrate the feasibility of airborne wireless optical communication system using an unmanned aerial vehicle and LEDs. Monte Carlo simulation method is used to evaluate the performance of the communication channel. Considering OOK modulation, we illustrate how the BER performance is affected by the link distance, the divergence angel and the deflection angel of the light source.

  17. Techniques for inferring terrain parameters related to ground vehicle mobility using UAV born IFSAR and lidar data

    NASA Astrophysics Data System (ADS)

    Durst, Phillip J.; Baylot, Alex; McKinley, Burney

    2011-05-01

    Predicting ground vehicle performance requires in-depth knowledge, captured as numeric parameters, of the terrain on which the vehicles will be operating. For off-road performance, predictions are based on rough terrain ride comfort, which is described using a parameter entitled root-mean-square (RMS) surface roughness. Likewise, on-road vehicle performance depends heavily on the slopes of the individual road segments. Traditional methods of computing RMS and road slope values call for high-resolution (inch-scale) surface elevation data. At this scale, surface elevation data is both difficult and time consuming to collect. Nevertheless, a current need exists to attribute large geographic areas with RMS and road slope values in order to better support vehicle mobility predictions, and high-resolution surface data is neither available nor collectible for many of these regions. On the other hand, meter scale data can be quickly and easily collected for these areas using unmanned aerial vehicle (UAV) based IFSAR and LIDAR sensors. A statistical technique for inferring RMS values for large areas using a combination of fractal dimension and spectral analysis of five-meter elevation data is presented. Validation of the RMS prediction technique was based on 43 vehicle ride courses with 30-centimeter surface elevation data. Also presented is a model for classifying road slopes for long road sections using five-meter elevation data. The road slope model was validated against one-meter LIDAR surface elevation profiles. These inference algorithms have been successfully implemented for regions of northern Afghanistan, and some initial results are presented.

  18. Uav Onboard Photogrammetry and GPS Positionning for Earthworks

    NASA Astrophysics Data System (ADS)

    Daakir, M.; Pierrot-Deseilligny, M.; Bosser, P.; Pichard, F.; Thom, C.

    2015-08-01

    Over the last decade, Unmanned Airbone Vehicles (UAVs) have been largely used for civil applications. Airborne photogrammetry has found place in these applications not only for 3D modeling but also as a measurement tool. Vinci-Construction-Terrassement is a private company specialized in public works sector and uses airborn photogrammetry as a mapping solution and metrology investigation tool on its sites. This technology is very efficient for the calculation of stock volumes for instance, or for time tracking of specific areas with risk of landslides. The aim of the present work is to perform a direct georeferencing of images acquired by the camera leaning on an embedded GPS receiver. UAV, GPS receiver and camera used are low-cost models and therefore data processing is adapted to this particular constraint.

  19. Thermal Imaging of Subsurface Coal Fires by means of an Unmanned Aerial Vehicle (UAV) in the Autonomous Province Xinjiang, PRC

    NASA Astrophysics Data System (ADS)

    Vasterling, Margarete; Schloemer, Stefan; Fischer, Christian; Ehrler, Christoph

    2010-05-01

    Spontaneous combustion of coal and resulting coal fires lead to very high temperatures in the subsurface. To a large amount the heat is transferred to the surface by convective and conductive transport inducing a more or less pronounced thermal anomaly. During the past decade satellite-based infrared-imaging (ASTER, MODIS) was the method of choice for coal fire detection on a local and regional scale. However, the resolution is by far too low for a detailed analysis of single coal fires which is essential prerequisite for corrective measures (i.e. fire fighting) and calculation of carbon dioxide emission based on a complex correlation between energy release and CO2 generation. Consequently, within the framework of the Sino-German research project "Innovative Technologies for Exploration, Extinction and Monitoring of Coal Fires in Northern China", a new concept was developed and successfully tested. An unmanned aerial vehicle (UAV) was equipped with a lightweight camera for thermografic (resolution 160 by 120 pixel, dynamic range -20 to 250°C) and for visual imaging. The UAV designed as an octocopter is able to hover at GPS controlled waypoints during predefined flight missions. The application of a UAV has several advantages. Compared to point measurements on the ground the thermal imagery quickly provides the spatial distribution of the temperature anomaly with a much better resolution. Areas otherwise not accessible (due to topography, fire induced cracks, etc.) can easily be investigated. The results of areal surveys on two coal fires in Xinjiang are presented. Georeferenced thermal and visual images were mosaicked together and analyzed. UAV-born data do well compared to temperatures measured directly on the ground and cover large areas in detail. However, measuring surface temperature alone is not sufficient. Simultaneous measurements made at the surface and in roughly 15cm depth proved substantial temperature gradients in the upper soil. Thus the temperature

  20. Long-Term Tracking of a Specific Vehicle Using Airborne Optical Camera Systems

    NASA Astrophysics Data System (ADS)

    Kurz, F.; Rosenbaum, D.; Runge, H.; Cerra, D.; Mattyus, G.; Reinartz, P.

    2016-06-01

    In this paper we present two low cost, airborne sensor systems capable of long-term vehicle tracking. Based on the properties of the sensors, a method for automatic real-time, long-term tracking of individual vehicles is presented. This combines the detection and tracking of the vehicle in low frame rate image sequences and applies the lagged Cell Transmission Model (CTM) to handle longer tracking outages occurring in complex traffic situations, e.g. tunnels. The CTM model uses the traffic conditions in the proximities of the target vehicle and estimates its motion to predict the position where it reappears. The method is validated on an airborne image sequence acquired from a helicopter. Several reference vehicles are tracked within a range of 500m in a complex urban traffic situation. An artificial tracking outage of 240m is simulated, which is handled by the CTM. For this, all the vehicles in the close proximity are automatically detected and tracked to estimate the basic density-flow relations of the CTM model. Finally, the real and simulated trajectories of the reference vehicles in the outage are compared showing good correspondence also in congested traffic situations.

  1. Building Information Modelling (BIM) and Unmanned Aerial Vehicle (UAV) technologies in infrastructure construction project management and delay and disruption analysis

    NASA Astrophysics Data System (ADS)

    Vacanas, Yiannis; Themistocleous, Kyriacos; Agapiou, Athos; Hadjimitsis, Diofantos

    2015-06-01

    Time in infrastructure construction projects has always been a fundamental issue as early as from the inception of a project, during the construction process and often after the completion and delivery. In a typical construction contract time related matters such as the completion date and possible delays are among the most important issues that are dealt with by the contract provisions. In the event of delay there are usually provisions for extension of time award to the contractor with possible reimbursement for the extra cost and expenses caused by this extension of time to the contract duration. In the case the contractor is not entitled to extension of time, the owner will be possibly entitled to amounts as compensation for the time prohibited from using his development. Even in the event of completion within the time agreed, under certain circumstances a contractor may have claims for reimbursement for extra costs incurred due to induced acceleration measures he had to take in order to mitigate disruption effects caused to the progress of the works by the owner or his representatives. Depending on the size of the project and the agreement amount, these reimbursement sums may be extremely high. Therefore innovative methods with the exploitation of new technologies for effective project management for the avoidance of delays, delay analysis and mitigation measures are essential; moreover, methods for collecting efficiently information during the construction process so that disputes regarding time are avoided or resolved in a quick and fair manner are required. This paper explores the state of art for existing use of Building Information Modelling (BIM) and Unmanned Aerial Vehicles (UAV) technologies in the construction industry in general. Moreover the paper considers the prospect of using BIM technology in conjunction with the use of UAV technology for efficient and accurate as-built data collection and illustration of the works progress during an

  2. Clutter effects on airborne tracking resolution requirements for urban vehicles

    NASA Astrophysics Data System (ADS)

    Robinson, Aaron L.; Miller, Brian; Richardson, Phillip; Ra, Chun

    2010-04-01

    This paper details the development, experimentation, collected data and the results of research designed to gain an understanding of the effects of clutter on the temporal and spatial image collection guidelines for tracking urban vehicles. More specifically, a quantitative understanding of the relationship between human observer performance and the spatial and temporal resolution is sought. Performance is measured as a function of the number of video frames per second, imager spatial resolution and the ability of the observer to accurately determine the destination of a moving vehicle target as it encounters vehicles with similar infrared signatures. The research is restricted to data and imagery collected from altitudes typical of modern low to mid altitude persistent surveillance platforms using a wide field of view. The ability of the human observer to perform an unaided track of the vehicle was determined by their completion of carefully designed perception experiments. In these experiments, the observers were presented with simulated imagery from Night Vision's EOSim urban terrain simulator. The details of the simulated targets and backgrounds, the design of the experiments and their associated results are included in this treatment.

  3. UNMANNED AERIAL VEHICLE (UAV) HYPERSPECTRAL REMOTE SENSING FOR DRYLAND VEGETATION MONITORING

    SciTech Connect

    Nancy F. Glenn; Jessica J. Mitchell; Matthew O. Anderson; Ryan C. Hruska

    2012-06-01

    UAV-based hyperspectral remote sensing capabilities developed by the Idaho National Lab and Idaho State University, Boise Center Aerospace Lab, were recently tested via demonstration flights that explored the influence of altitude on geometric error, image mosaicking, and dryland vegetation classification. The test flights successfully acquired usable flightline data capable of supporting classifiable composite images. Unsupervised classification results support vegetation management objectives that rely on mapping shrub cover and distribution patterns. Overall, supervised classifications performed poorly despite spectral separability in the image-derived endmember pixels. Future mapping efforts that leverage ground reference data, ultra-high spatial resolution photos and time series analysis should be able to effectively distinguish native grasses such as Sandberg bluegrass (Poa secunda), from invasives such as burr buttercup (Ranunculus testiculatus) and cheatgrass (Bromus tectorum).

  4. UAV visual signature suppression via adaptive materials

    NASA Astrophysics Data System (ADS)

    Barrett, Ron; Melkert, Joris

    2005-05-01

    Visual signature suppression (VSS) methods for several classes of aircraft from WWII on are examined and historically summarized. This study shows that for some classes of uninhabited aerial vehicles (UAVs), primary mission threats do not stem from infrared or radar signatures, but from the amount that an aircraft visually stands out against the sky. The paper shows that such visual mismatch can often jeopardize mission success and/or induce the destruction of the entire aircraft. A psycho-physioptical study was conducted to establish the definition and benchmarks of a Visual Cross Section (VCS) for airborne objects. This study was centered on combining the effects of size, shape, color and luminosity or effective illumance (EI) of a given aircraft to arrive at a VCS. A series of tests were conducted with a 6.6ft (2m) UAV which was fitted with optically adaptive electroluminescent sheets at altitudes of up to 1000 ft (300m). It was shown that with proper tailoring of the color and luminosity, the VCS of the aircraft dropped from more than 4,200cm2 to less than 1.8cm2 at 100m (the observed lower limit of the 20-20 human eye in this study). In laypersons terms this indicated that the UAV essentially "disappeared". This study concludes with an assessment of the weight and volume impact of such a Visual Suppression System (VSS) on the UAV, showing that VCS levels on this class UAV can be suppressed to below 1.8cm2 for aircraft gross weight penalties of only 9.8%.

  5. Water level observations from Unmanned Aerial Vehicles (UAVs) for improving probabilistic estimations of interaction between rivers and groundwater

    NASA Astrophysics Data System (ADS)

    Bandini, Filippo; Butts, Michael; Vammen Jacobsen, Torsten; Bauer-Gottwein, Peter

    2016-04-01

    Integrated hydrological models are generally calibrated against observations of river discharge and piezometric head in groundwater aquifers. Integrated hydrological models are rarely calibrated against spatially distributed water level observations measured by either in-situ stations or spaceborne platforms. Indeed in-situ observations derived from ground-based stations are generally spaced too far apart to capture spatial patterns in the water surface. On the other hand spaceborne observations have limited spatial resolution. Additionally satellite observations have a temporal resolution which is not ideal for observing the temporal patterns of the hydrological variables during extreme events. UAVs (Unmanned Aerial Vehicles) offer several advantages: i) high spatial resolution; ii) tracking of the water body better than any satellite technology; iii) timing of the sampling merely depending on the operators. In this case study the Mølleåen river (Denmark) and its catchment have been simulated through an integrated hydrological model (MIKE 11-MIKE SHE). This model was initially calibrated against observations of river discharge retrieved by in-situ stations and against piezometric head of the aquifers. Subsequently the hydrological model has been calibrated against dense spatially distributed water level observations, which could potentially be retrieved by UAVs. Error characteristics of synthetic UAV water level observations were taken from a recent proof-of-concept study. Since the technology for ranging water level is under development, UAV synthetic water level observations were extracted from another model of the river with higher spatial resolution (cross sections located every 10 m). This model with high resolution is assumed to be absolute truth for the purpose of this work. The river model with the coarser resolution has been calibrated against the synthetic water level observations through Differential Evolution Adaptive Metropolis (DREAM) algorithm, an

  6. UAV Cooperation Architectures for Persistent Sensing

    SciTech Connect

    Roberts, R S; Kent, C A; Jones, E D

    2003-03-20

    With the number of small, inexpensive Unmanned Air Vehicles (UAVs) increasing, it is feasible to build multi-UAV sensing networks. In particular, by using UAVs in conjunction with unattended ground sensors, a degree of persistent sensing can be achieved. With proper UAV cooperation algorithms, sensing is maintained even though exceptional events, e.g., the loss of a UAV, have occurred. In this paper a cooperation technique that allows multiple UAVs to perform coordinated, persistent sensing with unattended ground sensors over a wide area is described. The technique automatically adapts the UAV paths so that on the average, the amount of time that any sensor has to wait for a UAV revisit is minimized. We also describe the Simulation, Tactical Operations and Mission Planning (STOMP) software architecture. This architecture is designed to help simulate and operate distributed sensor networks where multiple UAVs are used to collect data.

  7. Research for new UAV capabilities

    SciTech Connect

    Canavan, G.H.; Leadabrand, R.

    1996-07-01

    This paper discusses research for new Unmanned Aerial Vehicles (UAV) capabilities. Findings indicate that UAV performance could be greatly enhanced by modest research. Improved sensors and communications enhance near term cost effectiveness. Improved engines, platforms, and stealth improve long term effectiveness.

  8. The combined use of Building Information Modelling (BIM) and Unmanned Aerial Vehicle (UAV) technologies for the 3D illustration of the progress of works in infrastructure construction projects

    NASA Astrophysics Data System (ADS)

    Vacanas, Yiannis; Themistocleous, Kyriacos; Agapiou, Athos; Hadjimitsis, Diofantos

    2016-08-01

    Building Information Modelling (BIM) technology is already part of the construction industry and is considered by professionals as a very useful tool for all phases of a construction project. BIM technology, with the particularly useful 3D illustrations which it provides, can be used to illustrate and monitor the progress of works effectively through the entire lifetime of the project. Unmanned Aerial Vehicles (UAVs) have undergone significant advances in equipment capabilities and now have the capacity to acquire high resolution imagery from different angles in a cost effective and efficient manner. By using photogrammetry, characteristics such as distances, areas, volumes, elevations, object sizes, and object shape can be determined within overlapping areas. This paper explores the combined use of BIM and UAV technologies in order to achieve efficient and accurate as-built data collection and 3D illustrations of the works progress during an infrastructure construction project.

  9. Unmanned Aerial Vehicle (UAV) operated spectral camera system for forest and agriculture applications

    NASA Astrophysics Data System (ADS)

    Saari, Heikki; Pellikka, Ismo; Pesonen, Liisa; Tuominen, Sakari; Heikkilä, Jan; Holmlund, Christer; Mäkynen, Jussi; Ojala, Kai; Antila, Tapani

    2011-11-01

    VTT Technical Research Centre of Finland has developed a Fabry-Perot Interferometer (FPI) based hyperspectral imager compatible with the light weight UAV platforms. The concept of the hyperspectral imager has been published in the SPIE Proc. 7474 and 7668. In forest and agriculture applications the recording of multispectral images at a few wavelength bands is in most cases adequate. The possibility to calculate a digital elevation model of the forest area and crop fields provides means to estimate the biomass and perform forest inventory. The full UAS multispectral imaging system will consist of a high resolution false color imager and a FPI based hyperspectral imager which can be used at resolutions from VGA (480 x 640 pixels) up to 5 Mpix at wavelength range 500 - 900 nm at user selectable spectral resolutions in the range 10...40 nm @ FWHM. The resolution is determined by the order at which the Fabry- Perot interferometer is used. The overlap between successive images of the false color camera is 70...80% which makes it possible to calculate the digital elevation model of the target area. The field of view of the false color camera is typically 80 degrees and the ground pixel size at 150 m flying altitude is around 5 cm. The field of view of the hyperspectral imager is presently is 26 x 36 degrees and ground pixel size at 150 m flying altitude is around 3.5 cm. The UAS system has been tried in summer 2011 in Southern Finland for the forest and agricultural areas. During the first test campaigns the false color camera and hyperspectral imager were flown over the target areas at separate flights. The design and calibration of the hyperspectral imager will be shortly explained. The test flight campaigns on forest and crop fields and their preliminary results are also presented in this paper.

  10. Behaviour recognition of ground vehicle using airborne monitoring of unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Oh, Hyondong; Kim, Seungkeun; Shin, Hyo-Sang; Tsourdos, Antonios; White, Brian A.

    2014-12-01

    This paper proposes a behaviour recognition methodology for ground vehicles moving within road traffic using unmanned aerial vehicles in order to identify suspicious or abnormal behaviour. With the target information acquired by unmanned aerial vehicles and estimated by filtering techniques, ground vehicle behaviour is first classified into representative driving modes, and then a string pattern matching theory is applied to detect suspicious behaviours in the driving mode history. Furthermore, a fuzzy decision-making process is developed to systematically exploit all available information obtained from a complex environment and confirm the characteristic of behaviour, while considering spatiotemporal environment factors as well as several aspects of behaviours. To verify the feasibility and benefits of the proposed approach, numerical simulations on moving ground vehicles are performed using realistic car trajectory data from an off-the-shelf traffic simulation software.

  11. Uav Data Processing for Rapid Mapping Activities

    NASA Astrophysics Data System (ADS)

    Tampubolon, W.; Reinhardt, W.

    2015-08-01

    During disaster and emergency situations, geospatial data plays an important role to serve as a framework for decision support system. As one component of basic geospatial data, large scale topographical maps are mandatory in order to enable geospatial analysis within quite a number of societal challenges. The increasing role of geo-information in disaster management nowadays consequently needs to include geospatial aspects on its analysis. Therefore different geospatial datasets can be combined in order to produce reliable geospatial analysis especially in the context of disaster preparedness and emergency response. A very well-known issue in this context is the fast delivery of geospatial relevant data which is expressed by the term "Rapid Mapping". Unmanned Aerial Vehicle (UAV) is the rising geospatial data platform nowadays that can be attractive for modelling and monitoring the disaster area with a low cost and timely acquisition in such critical period of time. Disaster-related object extraction is of special interest for many applications. In this paper, UAV-borne data has been used for supporting rapid mapping activities in combination with high resolution airborne Interferometric Synthetic Aperture Radar (IFSAR) data. A real disaster instance from 2013 in conjunction with Mount Sinabung eruption, Northern Sumatra, Indonesia, is used as the benchmark test for the rapid mapping activities presented in this paper. On this context, the reliable IFSAR dataset from airborne data acquisition in 2011 has been used as a comparable dataset for accuracy investigation and assessment purpose in 3 D reconstructions. After all, this paper presents a proper geo-referencing and feature extraction method of UAV data to support rapid mapping activities.

  12. Quantitative Measurement of Soil Erosion from Tls and Uav Data

    NASA Astrophysics Data System (ADS)

    Eltner, A.; Mulsow, C.; Maas, H.-G.

    2013-08-01

    Soil erosion is a major issue concerning crop land degradation. Understanding these complex erosion processes is necessary for effective soil conservation. Herein, high resolution modelling of relief changes caused by run-off from precipitation events is an essential research matter. For non-invasive field measurements the combination of unmanned airborne vehicle (UAV) image data and terrestrial laser scanning (TLS) may be especially suitable. The study's objective is to measure high precision digital terrain models (DTM) of the soil surface at two selected research areas with the extent of at least 500 square meters. The used UAV is integrated with GPS and inertial measurement unit (IMU). Furthermore, an active stabilizing camera mount equipped with a customary compact camera is implemented. For multi-temporal comparison of measured soil surfaces and for aligning UAV and TLS data a stable local reference system consisting of signalized points is defined by total station measurements. Two different software packages are applied for DTM generation from UAV images and compared to the corresponding DTM captured by TLS. Differences between the point clouds are minimal six millimeters and generally within TLS accuracy range. First multi-temporal comparisons are made and illustrate interesting surface changes.

  13. Evaluating the accuracy of orthophotos and 3D models from UAV photogrammetry

    NASA Astrophysics Data System (ADS)

    Julge, Kalev; Ellmann, Artu

    2015-04-01

    Rapid development of unmanned aerial vehicles (UAV) in recent years has made their use for various applications more feasible. This contribution evaluates the accuracy and quality of different UAV remote sensing products (i.e. orthorectified image, point cloud and 3D model). Two different autonomous fixed wing UAV systems were used to collect the aerial photographs. One is a mass-produced commercial UAV system, the other is a similar state-of-the-art UAV system. Three different study areas with varying sizes and characteristics (including urban areas, forests, fields, etc.) were surveyed. The UAV point clouds, 3D models and orthophotos were generated with three different commercial and free-ware software. The performance of each of these was evaluated. The effect of flying height on the accuracy of the results was explored, as well as the optimum number and placement of ground control points. Also the achieved results, when the only georeferencing data originates from the UAV system's on-board GNSS and inertial measurement unit, are investigated. Problems regarding the alignment of certain types of aerial photos (e.g. captured over forested areas) are discussed. The quality and accuracy of UAV photogrammetry products are evaluated by comparing them with control measurements made with GNSS-measurements on the ground, as well as high-resolution airborne laser scanning data and other available orthophotos (e.g. those acquired for large scale national mapping). Vertical comparisons are made on surfaces that have remained unchanged in all campaigns, e.g. paved roads. Planar comparisons are performed by control surveys of objects that are clearly identifiable on orthophotos. The statistics of these differences are used to evaluate the accuracy of UAV remote sensing. Some recommendations are given on how to conduct UAV mapping campaigns cost-effectively and with minimal time-consumption while still ensuring the quality and accuracy of the UAV data products. Also the

  14. Development and Evaluation of a Uav Based Mapping System for Remote Sensing and Surveying Applications

    NASA Astrophysics Data System (ADS)

    Eling, C.; Wieland, M.; Hess, C.; Klingbeil, L.; Kuhlmann, H.

    2015-08-01

    In recent years, unmanned aerial vehicles (UAVs) have increasingly been used in various application areas, such as in the remote sensing or surveying. For these applications the UAV has to be equipped with a mapping sensor, which is mostly a camera. Furthermore, a georeferencing of the UAV platform and/or the acquired mapping data is required. The most efficient way to realize this georeferencing is the direct georeferencing, which is based on an onboard multi-sensor system. In recent decades, direct georeferencing systems have been researched and used extensively in airborne, ship and land vehicle applications. However, these systems cannot easily be adapted to UAV platforms, which is mainly due to weight and size limitations. In this paper a direct georeferencing system for micro- and mini-sized UAVs is presented, which consists of a dual-frequency geodetic grade OEM GPS board, a low-cost single-frequency GPS chip, a tactical grade IMU and a magnetometer. To allow for cm-level position and sub-degree attitude accuracies, RTK GPS (real-time kinematic) and GPS attitude (GPS compass) determination algorithms are running on this system, as well as a GPS/IMU integration. Beside the direct georeferencing, also the precise time synchronization of the camera, which acts as the main sensor for mobile mapping applications, and the calibration of the lever arm between the camera reference point and the direct georeferencing reference point are explained in this paper. Especially the high accurate time synchronization of the camera is very important, to still allow for high surveying accuracies, when the images are taken during the motion of the UAV. Results of flight tests demonstrate that the developed system, the camera synchronization and the lever arm calibration make directly georeferenced UAV based single point measurements possible, which have cm-level accuracies on the ground.

  15. Developing a fixed-wing UAV aeromagnetic system

    NASA Astrophysics Data System (ADS)

    Ziqi, G.

    2013-12-01

    This invention relates to a fixed-wing unmanned aerial vehicle (UAV) aeromagnetic system which is suitable for geophysical prospecting using earth magnetic fields and to develop a low cost, easy operation, reliable performance of aerial magnetic detection system. This system depends mainly upon the measurement of the magnetic properties of the underlying ground. This big project contained unmanned aerial vehicle system, battery system for power source, navigation and flight control system, magnetometer, the magnetic compensation and data processing system and compare with the ground demonstration area. Each of them is a complex engineer system. We made two kind of fixed-wing UAV which designed for different magnetometers such as Helium airborne optical pumping magnetometer and SQUID magnetometer. The battery designed to endure large range temperature varied from -30 to 60 Celsius degree with a dual-redundancy system. A primary object of the invention to provide a fixed-wing UAV for deep exploration using natural magneto-telluric fields as an energy source and operating in a frequency of 20Hz, the System integrated precision of 2nT ranged from 19000 nT to 74000 nT, Meeting the demand of global resources exploration. Another object is it can operate at much higher terrain to 5000km. Yet another object of the invention is providing a system that can explore for mineral deposits with mountain and some other terrain. This paper Sponsored by the project of Chinese deep explorations (SinoProbe09-03)

  16. Hyperspectral imaging system for UAV

    NASA Astrophysics Data System (ADS)

    Zhang, Da; Zheng, Yuquan

    2015-10-01

    Hyperspectral imaging system for Unmanned Aerial Vehicle (UAV) is proposed under airborne remote sensing application background. By the application of Offner convex spherical grating spectral imaging system and using large area array detector push-broom imaging, hyperspectral imaging system with the indicators of 0.4μm to 1.0μm spectral range, 120 spectral bands, 5nm spectral resolution and 1m ground sampling interval (flight altitude 5km) is developed and completed. The Offner convex grating spectral imaging system is selected to achieve non-spectral line bending and colorless distortion design results. The diffraction efficiency is 15%-30% in the range of 0.4μm to 1.0μm wavelength. The system performances are tested by taking spectral and radiometric calibration methods in the laboratory. Based on monochromatic collimated light method for spectral performance parameters calibration of hyperspectral optical remote sensor, the analysis results of spectral calibration data show that the calibration test repeatability is less than 0.2 nm within one hour. The spectral scaling results show that the average spectral resolution of hyperspectral optical remote sensor is 4.94 nm, and the spatial dimension of the high-spectral optical remote sensor spectral resolution is less than 5 nm, the average of the typical spectral bandwidth is about 6 nm, the system average signal-to-noise ratio (SNR) is up to 43dB under typical operating conditions. Finally the system functionalities and performance indicators are verified by the aviation flight tests, which it's equipped on UAV. The actual image quality is good, and the spectral position is stable.

  17. Object-Based Change Detection Using Georeferenced Uav Images

    NASA Astrophysics Data System (ADS)

    Shi, J.; Wang, J.; Xu, Y.

    2011-09-01

    Unmanned aerial vehicles (UAV) have been widely used to capture and down-link real-time videos/images. However, their role as a low-cost airborne platform for capturing high-resolution, geo-referenced still imagery has not been fully utilized. The images obtained from UAV are advantageous over remote sensing images as they can be obtained at a low cost and potentially no risk to human life. However, these images are distorted due to the noise generated by the rotary wings which limits the usefulness of such images. One potential application of such images is to detect changes between the images of the same area which are collected over time. Change detection is of widespread interest due to a large number of applications, including surveillance and civil infrastructure. Although UAVs can provide images with high resolution in a portable and easy way, such images only cover small parts of the entire field of interest and are often with high deformation. Until now, there is not much application of change detection for UAV images. Also the traditional pixel-based change detection method does not give satisfactory results for such images. In this paper, we have proposed a novel object-based method for change detection using UAV images which can overcome the effect of deformation and can fully utilize the high resolution capability of UAV images. The developed method can be divided into five main blocks: pre-processing, image matching, image segmentation and feature extraction, change detection and accuracy evaluation. The pre-processing step is further divided into two sub-steps: the first sub-step is to geometrically correct the bi-temporal image based on the geo-reference information (GPS/INS) installed on the UAV system, and the second sub-step is the radiometric normalization using a histogram method. The image matching block uses the well-known scale-invariant feature transform (SIFT) algorithm to match the same areas in the images and then resample them. The

  18. Landing strategies in honeybees, and possible applications to autonomous airborne vehicles.

    PubMed

    Srinivasan, M V; Zhang, S; Chahl, J S

    2001-04-01

    Insects, being perhaps more reliant on image motion cues than mammals or higher vertebrates, are proving to be an excellent organism in which to investigate how information on optic flow is exploited to guide locomotion and navigation. This paper describes one example, illustrating how bees perform grazing landings on a flat surface. A smooth landing is achieved by a surprisingly simple and elegant strategy: image velocity is held constant as the surface is approached, thus automatically ensuring that flight speed is close to zero at touchdown. No explicit knowledge of flight speed or height above the ground is necessary. The feasibility of this landing strategy is tested by implementation in a robotic gantry, and its applicability to autonomous airborne vehicles is discussed. PMID:11341587

  19. Landing strategies in honeybees, and possible applications to autonomous airborne vehicles.

    PubMed

    Srinivasan, M V; Zhang, S; Chahl, J S

    2001-04-01

    Insects, being perhaps more reliant on image motion cues than mammals or higher vertebrates, are proving to be an excellent organism in which to investigate how information on optic flow is exploited to guide locomotion and navigation. This paper describes one example, illustrating how bees perform grazing landings on a flat surface. A smooth landing is achieved by a surprisingly simple and elegant strategy: image velocity is held constant as the surface is approached, thus automatically ensuring that flight speed is close to zero at touchdown. No explicit knowledge of flight speed or height above the ground is necessary. The feasibility of this landing strategy is tested by implementation in a robotic gantry, and its applicability to autonomous airborne vehicles is discussed.

  20. [Retrieval of crown closure of moso bamboo forest using unmanned aerial vehicle (UAV) remotely sensed imagery based on geometric-optical model].

    PubMed

    Wang, Cong; Du, Hua-qiang; Zhou, Guo-mo; Xu, Xiao-jun; Sun, Shao-bo; Gao, Guo-long

    2015-05-01

    This research focused on the application of remotely sensed imagery from unmanned aerial vehicle (UAV) with high spatial resolution for the estimation of crown closure of moso bamboo forest based on the geometric-optical model, and analyzed the influence of unconstrained and fully constrained linear spectral mixture analysis (SMA) on the accuracy of the estimated results. The results demonstrated that the combination of UAV remotely sensed imagery and geometric-optical model could, to some degrees, achieve the estimation of crown closure. However, the different SMA methods led to significant differentiation in the estimation accuracy. Compared with unconstrained SMA, the fully constrained linear SMA method resulted in higher accuracy of the estimated values, with the coefficient of determination (R2) of 0.63 at 0.01 level, against the measured values acquired during the field survey. Root mean square error (RMSE) of approximate 0.04 was low, indicating that the usage of fully constrained linear SMA could bring about better results in crown closure estimation, which was closer to the actual condition in moso bamboo forest.

  1. [Retrieval of crown closure of moso bamboo forest using unmanned aerial vehicle (UAV) remotely sensed imagery based on geometric-optical model].

    PubMed

    Wang, Cong; Du, Hua-qiang; Zhou, Guo-mo; Xu, Xiao-jun; Sun, Shao-bo; Gao, Guo-long

    2015-05-01

    This research focused on the application of remotely sensed imagery from unmanned aerial vehicle (UAV) with high spatial resolution for the estimation of crown closure of moso bamboo forest based on the geometric-optical model, and analyzed the influence of unconstrained and fully constrained linear spectral mixture analysis (SMA) on the accuracy of the estimated results. The results demonstrated that the combination of UAV remotely sensed imagery and geometric-optical model could, to some degrees, achieve the estimation of crown closure. However, the different SMA methods led to significant differentiation in the estimation accuracy. Compared with unconstrained SMA, the fully constrained linear SMA method resulted in higher accuracy of the estimated values, with the coefficient of determination (R2) of 0.63 at 0.01 level, against the measured values acquired during the field survey. Root mean square error (RMSE) of approximate 0.04 was low, indicating that the usage of fully constrained linear SMA could bring about better results in crown closure estimation, which was closer to the actual condition in moso bamboo forest. PMID:26571671

  2. Airborne brake wear debris: size distributions, composition, and a comparison of dynamometer and vehicle tests.

    PubMed

    Sanders, Paul G; Xu, Ning; Dalka, Tom M; Maricq, M Matti

    2003-09-15

    Particle size distributions of light-duty vehicle brake wear debris are reported with careful attention paid to avoid sampling biases. Electrical low-pressure impactor and micro-orifice uniform deposit impactor measurements yield consistent size distributions, and the net particulate matter mass from each method is in good agreement with gravimetric filter measurements. The mass mean diameter of wear debris from braking events representative of urban driving is 6 microm, and the number-weighted mean is 1-2 microm for three currently used classes of lining materials: low metallic, semimetallic, and non-asbestos organic (NAO). In contrast, the wear rates are very material dependent, both in number and mass of particles, with 3-4 times higher emissions observed from the low metallic linings as compared to the semimetallic and NAO linings. Wind tunnel and test track measurements demonstrate the appearance of micron size particles that correlate with braking events, with approximately 50% of the wear debris being airborne for the test vehicle in this study. Elemental analysis of the wear debris reveals a consistent presence of the elements Fe, Cu, and Ba in both dynamometer and test track samples. PMID:14524436

  3. Environmental effects on composite airframes: A study conducted for the ARM UAV Program (Atmospheric Radiation Measurement Unmanned Aerospace Vehicle)

    SciTech Connect

    Noguchi, R.A.

    1994-06-01

    Composite materials are affected by environments differently than conventional airframe structural materials are. This study identifies the environmental conditions which the composite-airframe ARM UAV may encounter, and discusses the potential degradation processes composite materials may undergo when subjected to those environments. This information is intended to be useful in a follow-on program to develop equipment and procedures to prevent, detect, or otherwise mitigate significant degradation with the ultimate goal of preventing catastrophic aircraft failure.

  4. Direct Georeferencing of Uav Data Based on Simple Building Structures

    NASA Astrophysics Data System (ADS)

    Tampubolon, W.; Reinhardt, W.

    2016-06-01

    Unmanned Aerial Vehicle (UAV) data acquisition is more flexible compared with the more complex traditional airborne data acquisition. This advantage puts UAV platforms in a position as an alternative acquisition method in many applications including Large Scale Topographical Mapping (LSTM). LSTM, i.e. larger or equal than 1:10.000 map scale, is one of a number of prominent priority tasks to be solved in an accelerated way especially in third world developing countries such as Indonesia. As one component of fundamental geospatial data sets, large scale topographical maps are mandatory in order to enable detailed spatial planning. However, the accuracy of the products derived from the UAV data are normally not sufficient for LSTM as it needs robust georeferencing, which requires additional costly efforts such as the incorporation of sophisticated GPS Inertial Navigation System (INS) or Inertial Measurement Unit (IMU) on the platform and/or Ground Control Point (GCP) data on the ground. To reduce the costs and the weight on the UAV alternative solutions have to be found. This paper outlines a direct georeferencing method of UAV data by providing image orientation parameters derived from simple building structures and presents results of an investigation on the achievable results in a LSTM application. In this case, the image orientation determination has been performed through sequential images without any input from INS/IMU equipment. The simple building structures play a significant role in such a way that geometrical characteristics have been considered. Some instances are the orthogonality of the building's wall/rooftop and the local knowledge of the building orientation in the field. In addition, we want to include the Structure from Motion (SfM) approach in order to reduce the number of required GCPs especially for the absolute orientation purpose. The SfM technique applied to the UAV data and simple building structures additionally presents an effective tool

  5. AVIATR - Aerial Vehicle for In-situ and Airborne Titan Reconnaissance A Titan Airplane Mission Concept

    NASA Technical Reports Server (NTRS)

    Barnes, Jason W.; Lemke, Lawrence; Foch, Rick; McKay, Christopher P.; Beyer, Ross A.; Radebaugh, Jani; Atkinson, David H.; Lorenz, Ralph D.; LeMouelic, Stephane; Rodriguez, Sebastien; Gundlach, Jay; Giannini, Francesco; Bain, Sean; Flasar, F. Michael; Hurford, Terry; Anderson, Carrie M.; Merrison, Jon; Adamkovics, Mate; Kattenhorn, Simon A.; Mitchell, Jonathan; Burr, Devon M.; Colaprete, Anthony; Schaller, Emily; Friedson, A. James; Edgett, Kenneth S.; Coradini, Angioletta; Adriani, Alberto; Sayanagi, Kunio M.; Malaska, Michael J.; Morabito, David; Reh, Kim

    2011-01-01

    We describe a mission concept for a stand-alone Titan airplane mission: Aerial Vehicle for In-situ and Airborne Titan Reconnaissance (AVIATR). With independent delivery and direct-to-Earth communications, AVIATR could contribute to Titan science either alone or as part of a sustained Titan Exploration Program. As a focused mission, AVIATR as we have envisioned it would concentrate on the science that an airplane can do best: exploration of Titan's global diversity. We focus on surface geology/hydrology and lower-atmospheric structure and dynamics. With a carefully chosen set of seven instruments-2 near-IR cameras, 1 near-IR spectrometer, a RADAR altimeter, an atmospheric structure suite, a haze sensor, and a raindrop detector-AVIATR could accomplish a significant subset of the scientific objectives of the aerial element of flagship studies. The AVIATR spacecraft stack is composed of a Space Vehicle (SV) for cruise, an Entry Vehicle (EV) for entry and descent, and the Air Vehicle (AV) to fly in Titan's atmosphere. Using an Earth-Jupiter gravity assist trajectory delivers the spacecraft to Titan in 7.5 years, after which the AVIATR AV would operate for a 1-Earth-year nominal mission. We propose a novel 'gravity battery' climb-then-glide strategy to store energy for optimal use during telecommunications sessions. We would optimize our science by using the flexibility of the airplane platform, generating context data and stereo pairs by flying and banking the AV instead of using gimbaled cameras. AVIATR would climb up to 14 km altitude and descend down to 3.5 km altitude once per Earth day, allowing for repeated atmospheric structure and wind measurements all over the globe. An initial Team-X run at JPL priced the AVIATR mission at FY10 $715M based on the rules stipulated in the recent Discovery announcement of opportunity. Hence we find that a standalone Titan airplane mission can achieve important science building on Cassini's discoveries and can likely do so within

  6. Analysis of material entrainment with an unmanned aerial vehicle (UAV) and simulation of the debris-flow event at the Sattelbach torrent - Austria, 2013.

    NASA Astrophysics Data System (ADS)

    Scheidl, Christian; Schraml, Klaus; Moser, Markus; Hübl, Johannes

    2014-05-01

    In summer 2013, a disastrous debris-flow destroyed several houses and infrastructure facilities on the fan of the Sattelbach catchment located in the district of St. Johann im Pongau, Salzburg (Austria). Fortunately, no damage to persons could be registered. The debris flow was triggered by shallow landslides within the upper catchment, mobilizing in total approximately 4,000 m3 of debris. However, the volume of the debris-flow event at the fan was documented with 12,000 m3, whereas a maximum discharge of 380 m3/s was estimated near the fan apex. Witnesses reported only one big wave passing the fan area, which seems to be out of character for a typical Alpine debris-flow event showing such high discharge. For the later, one would suppose multiple smaller waves. Due to the fact of evolving material entrainment resulted in one big wave, the debris-flow event at the Sattelbach catchment was chosen as case study to analyze mass bulking. For this reason, an unmanned aerial vehicle (UAV) was used to establish a digital terrain model (DTM) of the whole reach after the event. This terrain model was then compared to a LiDAR DTM, showing the topographical situation before the event. Based on the analyzed mass bulking along the whole reach, numerical simulations were performed using the DAN3D (Dynamic Analysis of Landslides in Three Dimensions) code. The DAN3D model allows selection between different rheologies as well as the implementation of entrainment. The study will show the applicability of UAV's in small and steep catchments and will test DAN 3D a debris-flow simulation tool with an implemented mass-bulking model.

  7. Bringing UAVs to the fight: recent army autonomy research and a vision for the future

    NASA Astrophysics Data System (ADS)

    Moorthy, Jay; Higgins, Raymond; Arthur, Keith

    2008-04-01

    The Unmanned Autonomous Collaborative Operations (UACO) program was initiated in recognition of the high operational burden associated with utilizing unmanned systems by both mounted and dismounted, ground and airborne warfighters. The program was previously introduced at the 62nd Annual Forum of the American Helicopter Society in May of 20061. This paper presents the three technical approaches taken and results obtained in UACO. All three approaches were validated extensively in contractor simulations, two were validated in government simulation, one was flight tested outside the UACO program, and one was flight tested in Part 2 of UACO. Results and recommendations are discussed regarding diverse areas such as user training and human-machine interface, workload distribution, UAV flight safety, data link bandwidth, user interface constructs, adaptive algorithms, air vehicle system integration, and target recognition. Finally, a vision for UAV As A Wingman is presented.

  8. Geomorphological mapping of shallow landslides using UAVs

    NASA Astrophysics Data System (ADS)

    Fiorucci, Federica; Giordan, Daniele; Dutto, Furio; Rossi, Mauro; Guzzetti, Fausto

    2015-04-01

    The mapping of event shallow landslides is a critical activity, due to the large number of phenomena, mostly with small dimension, affecting extensive areas. This is commonly done through aerial photo-interpretation or through field surveys. Nowadays, landslide maps can be realized exploiting other methods/technologies: (i) airborne LiDARs, (ii) stereoscopic satellite images, and (iii) unmanned aerial vehicles (UAVs). In addition to the landslide maps, these methods/technologies allow the generation of updated Digital Terrain Models (DTM). In December 2013, in the Collazzone area (Umbria, Central Italy), an intense rainfall event triggered a large number of shallow landslides. To map the landslides occurred in the area, we exploited data and images obtained through (A) an airborne LiDAR survey, (B) a remote controlled optocopter (equipped with a Canon EOS M) survey, and (C) a stereoscopic satellite WorldView II MS. To evaluate the mapping accuracy of these methods, we select two landslides and we mapped them using a GPS RTK instrumentation. We consider the GPS survey as the benchmark being the most accurate system. The results of the comparison allow to highlight pros and cons of the methods/technologies used. LiDAR can be considered the most accurate system and in addition it allows the extraction and the classification of the digital surface models from the surveyed point cloud. Conversely, LiDAR requires additional time for the flight planning, and specific data analysis user capabilities. The analysis of the satellite WorldView II MS images facilitates the landslide mapping over large areas, but at the expenses of a minor resolution to detect the smaller landslides and their boundaries. UAVs can be considered the cheapest and fastest solution for the acquisition of high resolution ortho-photographs on limited areas, and the best solution for a multi-temporal analysis of specific landslide phenomena. Limitations are due to (i) the needs of optimal climatic

  9. Final Report: High Spectral Resolution Atmospheric Emitted Radiance Studies with the ARM UAV

    SciTech Connect

    Revercomb, Henry E.

    1999-12-31

    The active participation in the Atmospheric Radiation Measurement (ARM) Unmanned Airborne Vehicle (UAV) science team that was anticipated in the grant proposal was indefinitely delayed after the first year due to a programmatic decision to exclude the high spectral resolution observations from the existing ARM UAV program. However, this report shows that substantial progress toward the science objectives of this grant have made with the help of separate funding from NASA and other agencies. In the four year grant period (including time extensions), a new high spectral resolution instrument has been flown and has successfully demonstrated the ability to obtain measurements of the type needed in the conduct of this grant. In the near term, the third water vapor intensive observing period (WVIOP-3) in October 2000 will provide an opportunity to bring the high spectral resolution observations of upwelling radiance into the ARM program to complement the downwelling radiance observations from the existing ARM AERI instruments. We look forward to a time when the ARM-UAV program is able to extend its scope to include the capability for making these high spectral resolution measurements from a UAV platform.

  10. Technology development of UAV recovery system based on laser detection

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi-wei; Lv, Hua

    2011-06-01

    The recovery technology of unmanned aerial vehicle (UAV) is one of the difficulties of UAV development. This paper presents an automatic UAV recovery guide system, which is based on laser detection technology. The guide system overcomes the problem that the small-sized UAV is not suitable for accurate-point recovery. Comparing to traditional recovery system, this system has some advantage, such as high precision, round-the-clock, flexible and easy testing. Especially, it improved the application level of UAV recovery system with corresponding orientation guide model and accurate orientation tracking technology. High requirements are needed for UAV near field distance measurement with this method. This paper provides a method for UAV close quarters navigation based on laser detection technology. It is a new application for computer vision and photoelectric technology, with fast safe secret and nil interference. UAV recovery system can lead the UAV to tackle net safely. According to current UAV technology development, using laser tracking as terminal guide sensor measure equipment is feasible. The distribution of UAV collision network callback system put the laser recovery guide system behind the tackle net. When the UAV enter the callback phase, laser call back system made the UAV slide down follow the direct orbit by way of searching tracking and orientation. The UAV recovery system setups biaxial automatic turntable, measure the horizontal angle and pitch angle change, provide the deviation of current flight path and destine flight path, also provides the distance information between UAV recovery system by the way of laser measurement. This thesis analyzes the feasibility of this technology, provides the workflow of the UAV when entering the call back process. This paper also presents the correction method of laser error. The simulation result shows this distance measure system can lead the UAV call back safely.

  11. Wireless Command-and-Control of UAV-Based Imaging LANs

    NASA Technical Reports Server (NTRS)

    Herwitz, Stanley; Dunagan, S. E.; Sullivan, D. V.; Slye, R. E.; Leung, J. G.; Johnson, L. F.

    2006-01-01

    Dual airborne imaging system networks were operated using a wireless line-of-sight telemetry system developed as part of a 2002 unmanned aerial vehicle (UAV) imaging mission over the USA s largest coffee plantation on the Hawaiian island of Kauai. A primary mission objective was the evaluation of commercial-off-the-shelf (COTS) 802.11b wireless technology for reduction of payload telemetry costs associated with UAV remote sensing missions. Predeployment tests with a conventional aircraft demonstrated successful wireless broadband connectivity between a rapidly moving airborne imaging local area network (LAN) and a fixed ground station LAN. Subsequently, two separate LANs with imaging payloads, packaged in exterior-mounted pressure pods attached to the underwing of NASA's Pathfinder-Plus UAV, were operated wirelessly by ground-based LANs over independent Ethernet bridges. Digital images were downlinked from the solar-powered aircraft at data rates of 2-6 megabits per second (Mbps) over a range of 6.5 9.5 km. An integrated wide area network enabled payload monitoring and control through the Internet from a range of ca. 4000 km during parts of the mission. The recent advent of 802.11g technology is expected to boost the system data rate by about a factor of five.

  12. Towards FAA Certification of UAVs

    NASA Technical Reports Server (NTRS)

    Nelson, Stacy

    2003-01-01

    As of June 30, 2003, all Unmanned Aerial Vehicles (UAV), no matter how small, must adhere to the same FAA regulations as human-piloted aircraft. These regulations include certification for flying in controlled airspace and certification of flight software based on RTCA DO-178B. This paper provides an overview of the steps necessary to obtain certification, as well as a discussion about the challenges UAV's face when trying to meet these requirements. It is divided into two parts: 1) Certifications for Flying in Controlled Airspace; 2) Certification of Flight Software per RTCA DO-178B.

  13. Towards a Biosynthetic UAV

    NASA Technical Reports Server (NTRS)

    Block, Eli; Byemerwa, Jovita; Dispenza, Ross; Doughty, Benjamin; Gillyard, KaNesha; Godbole, Poorwa; Gonzales-Wright, Jeanette; Hull, Ian; Kannappan, Jotthe; Levine, Alexander; Nelakanti, Raman; Ruffner, Lydia; Shumate, Alaina; Sorayya, Aryo; Ugwu, Kyla

    2014-01-01

    We are currently working on a series of projects towards the construction of a fully biological unmanned aerial vehicle (UAV) for use in scientific and humanitarian missions. The prospect of a biologically-produced UAV presents numerous advantages over the current manufacturing paradigm. First, a foundational architecture built by cells allows for construction or repair in locations where it would be difficult to bring traditional tools of production. Second, a major limitation of current research with UAVs is the size and high power consumption of analytical instruments, which require bulky electrical components and large fuselages to support their weight. By moving these functions into cells with biosensing capabilities - for example, a series of cells engineered to report GFP, green fluorescent protein, when conditions exceed a certain threshold concentration of a compound of interest, enabling their detection post-flight - these problems of scale can be avoided. To this end, we are working to engineer cells to synthesize cellulose acetate as a novel bioplastic, characterize biological methods of waterproofing the material, and program this material's systemic biodegradation. In addition, we aim to use an "amberless" system to prevent horizontal gene transfer from live cells on the material to microorganisms in the flight environment.

  14. UAV magnetometry in mineral exploration and infrastructure detection

    NASA Astrophysics Data System (ADS)

    Braun, A.; Parvar, K.; Burns, M.

    2015-12-01

    Magnetic surveys are critical tools in mineral exploration and UAVs have the potential to carry magnetometers. UAV surveys can offer higher spatial resolution than traditional airborne surveys, and higher coverage than terrestrial surveys. However, the main advantage is their ability to sense the magnetic field in 3-D, while most airborne or terrestrial surveys are restricted to 2-D acquisition. This study compares UAV magnetic data from two different UAVs (JIB drone, DJI Phantom 2) and three different magnetometers (GEM GSPM35, Honeywell HMR2300, GEM GST-19). The first UAV survey was conducted using a JIB UAV with a GSPM35 flying at 10-15 m above ground. The survey's goal was to detect intrusive Rhyolite bodies for primary mineral exploration. The survey resulted in a better understanding of the validity/resolution of UAV data and led to improved knowledge about the geological structures in the area. The results further drove the design of a following terrestrial survey. Comparing the UAV data with an available airborne survey (upward continued to 250 m) reveals that the UAV data has superior spatial resolution, but exhibits a higher noise level. The magnetic anomalies related to the Rhyolite intrusions is about 109 nT and translates into an estimated depth of approximately 110 meters. The second survey was conducted using an in-house developed UAV magnetometer system equipped with a DJI Phantom 2 and a Honeywell HMR2300 fluxgate magnetometer. By flying the sensor in different altitudes, the vertical and horizontal gradients can be derived leading to full 3-D magnetic data volumes which can provide improved constraints for source depth/geometry characterization. We demonstrate that a buried steam pipeline was detectable with the UAV magnetometer system and compare the resulting data with a terrestrial survey using a GEM GST-19 Proton Precession Magnetometer.

  15. Cooperative UAV-Based Communications Backbone for Sensor Networks

    SciTech Connect

    Roberts, R S

    2001-10-07

    The objective of this project is to investigate the use of unmanned air vehicles (UAVs) as mobile, adaptive communications backbones for ground-based sensor networks. In this type of network, the UAVs provide communication connectivity to sensors that cannot communicate with each other because of terrain, distance, or other geographical constraints. In these situations, UAVs provide a vertical communication path for the sensors, thereby mitigating geographic obstacles often imposed on networks. With the proper use of UAVs, connectivity to a widely disbursed sensor network in rugged terrain is readily achieved. Our investigation has focused on networks where multiple cooperating UAVs are used to form a network backbone. The advantage of using multiple UAVs to form the network backbone is parallelization of sensor connectivity. Many widely spaced or isolated sensors can be connected to the network at once using this approach. In these networks, the UAVs logically partition the sensor network into sub-networks (subnets), with one UAV assigned per subnet. Partitioning the network into subnets allows the UAVs to service sensors in parallel thereby decreasing the sensor-to-network connectivity. A UAV services sensors in its subnet by flying a route (path) through the subnet, uplinking data collected by the sensors, and forwarding the data to a ground station. An additional advantage of using multiple UAVs in the network is that they provide redundancy in the communications backbone, so that the failure of a single UAV does not necessarily imply the loss of the network.

  16. A study to identify and compare airborne systems for in-situ measurements of launch vehicle effluents

    NASA Technical Reports Server (NTRS)

    Thomas, T. J.; Chace, A. S.

    1974-01-01

    An in-situ system for monitoring the concentration of HCl, CO, CO2, and Al2O3 in the cloud of reaction products that form as a result of a launch of solid propellant launch vehicle is studied. A wide array of instrumentation and platforms are reviewed to yield the recommended system. An airborne system suited to monitoring pollution concentrations over urban areas for the purpose of calibrating remote sensors is then selected using a similar methodology to yield the optimal configuration.

  17. Development of Micro UAV Swarms

    NASA Astrophysics Data System (ADS)

    Bürkle, Axel; Leuchter, Sandro

    Some complex application scenarios for micro UAVs (Unmanned Aerial Vehicles) call for the formation of swarms of multiple drones. In this paper a platform for the creation of such swarms is presented. It consists of modified commercial quadrocopters and a self-made ground control station software architecture. Autonomy of individual drones is generated through a micro controller equipped video camera. Currently it is possible to fly basic maneuvers autonomously, such as take-off, fly to position, and landing. In the future the camera's image processing capabilities will be used to generate additional control information. Different co-operation strategies for teams of UAVs are currently evaluated with an agent based simulation tool. Finally complex application scenarios for multiple micro UAVs are presented.

  18. The Evaluation of GPS techniques for UAV-based Photogrammetry in Urban Area

    NASA Astrophysics Data System (ADS)

    Yeh, M. L.; Chou, Y. T.; Yang, L. S.

    2016-06-01

    The efficiency and high mobility of Unmanned Aerial Vehicle (UAV) made them essential to aerial photography assisted survey and mapping. Especially for urban land use and land cover, that they often changes, and need UAVs to obtain new terrain data and the new changes of land use. This study aims to collect image data and three dimensional ground control points in Taichung city area with Unmanned Aerial Vehicle (UAV), general camera and Real-Time Kinematic with positioning accuracy down to centimetre. The study area is an ecological park that has a low topography which support the city as a detention basin. A digital surface model was also built with Agisoft PhotoScan, and there will also be a high resolution orthophotos. There will be two conditions for this study, with or without ground control points and both were discussed and compared for the accuracy level of each of the digital surface models. According to check point deviation estimate, the model without ground control points has an average two-dimension error up to 40 centimeter, altitude error within one meter. The GCP-free RTK-airborne approach produces centimeter-level accuracy with excellent to low risk to the UAS operators. As in the case of the model with ground control points, the accuracy of x, y, z coordinates has gone up 54.62%, 49.07%, and 87.74%, and the accuracy of altitude has improved the most.

  19. Optical design of high resolution and large format CCD airborne remote sensing camera on unmanned aerial vehicle

    NASA Astrophysics Data System (ADS)

    Qian, Yixian; Cheng, Xiaowei; Shao, Jie

    2010-11-01

    Unmanned aerial vehicle remote sensing (UAVRS) is lower in cost, flexible on task arrangement and automatic and intelligent in application, it has been used widely for mapping, surveillance, reconnaissance and city planning. Airborne remote sensing missions require sensors with both high resolution and large fields of view, large format CCD digital airborne imaging systems are now a reality. A refractive system was designed to meet the requirements with the help of code V software, It has a focal length of 150mm, F number of 5.6, waveband of 0.45~0.7um, and field of view reaches 20°. It is shown that the value of modulation transfer function is higher than 0.5 at 55lp/mm, distortion is less than 0.1%, image quality reaches the diffraction limit. The system with large format CCD and wide field can satisfy the demand of the wide ground overlay area and high resolution. The optical system with simpler structure, smaller size and lighter weight, can be used in airborne remote sensing.

  20. An emergency response UAV Surveillance System.

    PubMed

    Rodriguez, Pedro A; Geckle, William J; Barton, Jeffrey D; Samsundar, John; Gao, Tia; Brown, Myron Z; Martin, Sean R

    2006-01-01

    A system using Unmanned Air Vehicles (UAVs), equipped for real time telemetry of video imagery, sensor support data, and GPS/INS navigation, is being developed to provide situational awareness (SA) to the central command of mass casualty incident response. UAVs provide an inexpensive and safe means of acquiring video surveillance in chaotic disaster scenes, while being durable and non-intrusive. The system provides autonomous surveillance of defined perimeters, video tracking and active following of targets of interest, and real time cueing to other imaging UAVs.

  1. Change Detection Experiments Using Low Cost UAVs

    NASA Technical Reports Server (NTRS)

    Logan, Michael J.; Vranas, Thomas L.; Motter, Mark; Hines, Glenn D.; Rahman, Zia-ur

    2005-01-01

    This paper presents the progress in the development of a low-cost change-detection system. This system is being developed to provide users with the ability to use a low-cost unmanned aerial vehicle (UAV) and image processing system that can detect changes in specific fixed ground locations using video provided by an autonomous UAV. The results of field experiments conducted with the US Army at Ft. A.P.Hill are presented.

  2. Evaluation of unmanned aerial vehicles (UAVs) for detection of cattle in the Cattle Fever Tick Permanent Quarantine Zone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An unmanned aerial vehicle was used to capture videos of cattle in pastures to determine the efficiency of this technology for use by Mounted Inspectors in the Permanent Quarantine zone (PQZ) of the Cattle Fever Tick Eradication Program in south Texas along the U.S.-Mexico Border. These videos were ...

  3. Airborne system for testing multispectral reconnaissance technologies

    NASA Astrophysics Data System (ADS)

    Schmitt, Dirk-Roger; Doergeloh, Heinrich; Keil, Heiko; Wetjen, Wilfried

    1999-07-01

    There is an increasing demand for future airborne reconnaissance systems to obtain aerial images for tactical or peacekeeping operations. Especially Unmanned Aerial Vehicles (UAVs) equipped with multispectral sensor system and with real time jam resistant data transmission capabilities are of high interest. An airborne experimental platform has been developed as testbed to investigate different concepts of reconnaissance systems before their application in UAVs. It is based on a Dornier DO 228 aircraft, which is used as flying platform. Great care has been taken to achieve the possibility to test different kinds of multispectral sensors. Hence basically it is capable to be equipped with an IR sensor head, high resolution aerial cameras of the whole optical spectrum and radar systems. The onboard equipment further includes system for digital image processing, compression, coding, and storage. The data are RF transmitted to the ground station using technologies with high jam resistance. The images, after merging with enhanced vision components, are delivered to the observer who has an uplink data channel available to control flight and imaging parameters.

  4. Demonstrating Acquisition of Real-Time Thermal Data over Fires Utilizing UAVs

    NASA Technical Reports Server (NTRS)

    Wegener, Steven S.; Ambrosia, Vincent G.; Stoneburner, Jay; Sullivan, Donald V.; Brass, James A.; Buechel, Sally W.; Higgins, Robert G.; Hildum, Edward A.; Schoenung, Susan M.; Peterson, David L. (Technical Monitor)

    2002-01-01

    NASA-Ames Research Center, in collaboration with General Atomics Aeronautical Systems, Inc. has been developing real-time data acquisition and information delivery systems employing uninhabited aerial vehicle (UAV) technology for disaster mitigation and assessment demonstrations. Working in conjunction with the US Forest Service, a disaster community agency responsible for wildfire management and mitigation, we developed a large-scale wildfire demonstration called the First Response Experiment (FIRE). During that experiment in late summer 2001, the participants demonstrated the melding of innovative technologies such as UAV platforms, real-time data processing, and data telemetry for quick analysis of a disaster event. The General Atomics ALTUS UAV, the Airborne Infrared Disaster Assessment System (AIRDAS) and Over-The-Horizon (OTH) satellite data telemetry equipment were employed over a controlled burn to test the feasibility of a disaster monitoring and mitigation platform for hazardous duty. The ALTUS UAV was employed to demonstrate the long duration, altitude, and payload capability of unmanned platforms for acquiring disaster related data. The ALTUS has an operational altitude to 45,000 feet (13,700 in), with a flight duration of twenty-four hours and a payload capacity of over 300 lbs. (148.5 kg). This allows the platform to operate under the conditions that would be necessary for monitoring and mitigating disaster events throughout the Unites States. The four channel AIRDAS data (calibrated thermal infrared digital imagery of the fire event) was sent from the ALTUS UAV via a satellite communications system (NERA transponder and INMARSAT satellite) to a data archive server and an image processing work station at NASA-Ames Research Center, 400 miles away.

  5. Automated UAV-based video exploitation using service oriented architecture framework

    NASA Astrophysics Data System (ADS)

    Se, Stephen; Nadeau, Christian; Wood, Scott

    2011-05-01

    Airborne surveillance and reconnaissance are essential for successful military missions. Such capabilities are critical for troop protection, situational awareness, mission planning, damage assessment, and others. Unmanned Aerial Vehicles (UAVs) gather huge amounts of video data but it is extremely labour-intensive for operators to analyze hours and hours of received data. At MDA, we have developed a suite of tools that can process the UAV video data automatically, including mosaicking, change detection and 3D reconstruction, which have been integrated within a standard GIS framework. In addition, the mosaicking and 3D reconstruction tools have also been integrated in a Service Oriented Architecture (SOA) framework. The Visualization and Exploitation Workstation (VIEW) integrates 2D and 3D visualization, processing, and analysis capabilities developed for UAV video exploitation. Visualization capabilities are supported through a thick-client Graphical User Interface (GUI), which allows visualization of 2D imagery, video, and 3D models. The GUI interacts with the VIEW server, which provides video mosaicking and 3D reconstruction exploitation services through the SOA framework. The SOA framework allows multiple users to perform video exploitation by running a GUI client on the operator's computer and invoking the video exploitation functionalities residing on the server. This allows the exploitation services to be upgraded easily and allows the intensive video processing to run on powerful workstations. MDA provides UAV services to the Canadian and Australian forces in Afghanistan with the Heron, a Medium Altitude Long Endurance (MALE) UAV system. On-going flight operations service provides important intelligence, surveillance, and reconnaissance information to commanders and front-line soldiers.

  6. Use of UAV to monitor and manage the territory during geo-hydrological hazards

    NASA Astrophysics Data System (ADS)

    Facello, Anna; Giordan, Daniele; Allasia, Paolo; Manconi, Andrea; Baldo, Marco; Dell'Anese, Federico

    2014-05-01

    In the last decades, the people and the societies are becoming more vulnerable; although the frequency of natural events may be constant, human activities contribute to their increased intensity. The demographic pressures and territory management have also largely contributed to an increase in natural disasters and environmental emergencies to society. Every year, millions of people are affected by natural disasters globally and more than 80% of all disaster-related deaths were caused by natural hazards. The use remote sensing has become a standard practice to monitor and analyze the evolution of the territory, mainly due to the wide development and availability of several sensors, which can operate on ground-based, airborne and space-borne platforms. In this context, Unmanned Aerial Vehicles (UAVs) have been increasingly considered also for remote sensing operations in civilian contexts and they play an important role in emergency management since they are capable of gathering valuable image information from low altitude for emergency management. In this work, we aim at detecting and simulating a relevant framework related to geo-hydrological risks, based on both real operational scenarios and on research and development in progress. In addition, we define strategies depending on UAV types (category, size, fixed or mobile wing) as well different sensors (Lidar, Radar, Hyperspectral, Digital Camera, Near Infrared) applied in different scenarios and area of investigation. We focus on the use of UAVs during geohazard emergencies, such as earthquake events, floods, and landslides. In particular, we present the results of theoretical context are applied to a real case, the "Cinque Terre" flood event (25 October 2011). We simulate the potential use of UAV platform in a real operating scenario, by using as reference the Cinque Terre Flood data and information. For this event we discuss and consider the main aspects relevant, highlighting the advantages and disadvantages

  7. The use of UAV platforms for remote sensing applications: case studies in Cyprus

    NASA Astrophysics Data System (ADS)

    Themistocleous, K.

    2014-08-01

    The use of cost-effective Unmanned Aerial Vehicles (UAVs) are becoming common tools for researchers for numerous applications. Since UAVs vary in size and payload capacity, various sensors can be installed onto the platform. UAVs can be a efficient and low cost resource for remote sensing applications. Different remote sensing techniques can be used with UAVs, such as field spectroscopy, multi-spectral cameras, infrared cameras and thermal cameras. This paper examines several UAV platforms that were used by the Cyprus University of Technology for remote sensing applications in Cyprus. Using these UAV systems for different applications, the advantages and disadvantages were examined and discussed.

  8. UAV Research, Operations, and Flight Test at the NASA Dryden Flight Research Center

    NASA Technical Reports Server (NTRS)

    Cosentino, Gary B.

    2009-01-01

    This slide presentation reviews some of the projects that have extended NASA Dryden's capabilities in designing, testing, and using Unmanned Aerial Vehicles (UAV's). Some of the UAV's have been for Science and experimental applications, some have been for flight research and demonstration purposes, and some have been small UAV's for other customers.

  9. Research on UAV Intelligent Obstacle Avoidance Technology During Inspection of Transmission Line

    NASA Astrophysics Data System (ADS)

    Wei, Chuanhu; Zhang, Fei; Yin, Chaoyuan; Liu, Yue; Liu, Liang; Li, Zongyu; Wang, Wanguo

    Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.

  10. Radical advancement in multi-spectral imaging for autonomous vehicles (UAVs, UGVs, and UUVs) using active compensation.

    SciTech Connect

    Clark, Brian F.; Bagwell, Brett E.; Wick, David Victor

    2007-01-01

    The purpose of this LDRD was to demonstrate a compact, multi-spectral, refractive imaging systems using active optical compensation. Compared to a comparable, conventional lens system, our system has an increased operational bandwidth, provides for spectral selectivity and, non-mechanically corrects aberrations induced by the wavelength dependent properties of a passive refractive optical element (i.e. lens). The compact nature and low power requirements of the system lends itself to small platforms such as autonomous vehicles. In addition, the broad spectral bandwidth of our system would allow optimized performance for both day/night use, and the multi-spectral capability allows for spectral discrimination and signature identification.

  11. Networking Multiple Autonomous Air and Ocean Vehicles for Oceanographic Research and Monitoring

    NASA Astrophysics Data System (ADS)

    McGillivary, P. A.; Borges de Sousa, J.; Rajan, K.

    2013-12-01

    Autonomous underwater and surface vessels (AUVs and ASVs) are coming into wider use as components of oceanographic research, including ocean observing systems. Unmanned airborne vehicles (UAVs) are now available at modest cost, allowing multiple UAVs to be deployed with multiple AUVs and ASVs. For optimal use good communication and coordination among vehicles is essential. We report on the use of multiple AUVs networked in communication with multiple UAVs. The UAVs are augmented by inferential reasoning software developed at MBARI that allows UAVs to recognize oceanographic fronts and change their navigation and control. This in turn allows UAVs to automatically to map frontal features, as well as to direct AUVs and ASVs to proceed to such features and conduct sampling via onboard sensors to provide validation for airborne mapping. ASVs can also act as data nodes for communication between UAVs and AUVs, as well as collecting data from onboard sensors, while AUVs can sample the water column vertically. This allows more accurate estimation of phytoplankton biomass and productivity, and can be used in conjunction with UAV sampling to determine air-sea flux of gases (e.g. CO2, CH4, DMS) affecting carbon budgets and atmospheric composition. In particular we describe tests in July 2013 conducted off Sesimbra, Portugal in conjunction with the Portuguese Navy by the University of Porto and MBARI with the goal of tracking large fish in the upper water column with coordinated air/surface/underwater measurements. A thermal gradient was observed in the infrared by a low flying UAV, which was used to dispatch an AUV to obtain ground truth to demonstrate the event-response capabilities using such autonomous platforms. Additional field studies in the future will facilitate integration of multiple unmanned systems into research vessel operations. The strength of hardware and software tools described in this study is to permit fundamental oceanographic measurements of both ocean

  12. UAV applications for thermodynamic profiling: Emphasis on ice fog research

    NASA Astrophysics Data System (ADS)

    Gultepe, Ismail; Heymsfield, Andrew J.; Fernando, Harindra J. S.; Hoch, Sebastian W.; Ware, Randolph

    2016-04-01

    Ice fog occurs often over the Arctic, cold climatic, and mountainous regions for about 30% of time where temperature (T) can go down to -10°C or below. Ice Nucleation (IN) and cooling processes play an important role by the controlling the intensity of ice fog conditions that affect aviation application, transportation, and local climate. Ice fog can also occur at T above -10°C but close to 0°C it occurs due to freezing of supercooled droplets that include an IN. To better document ice fog conditions, observations from the ice fog events of the Indirect and Semi-Direct Aerosol effects on Climate (ISDAC) project, Barrow, Alaska, Fog Remote Sensing And Modeling (FRAM) project Yellowknife, Northwest Territories, and the Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) project, Heber City, Utah, were analyzed.. Measurements difficulties of small ice fog particles at cold temperatures and low-level flying restrictions prevent observations from aircraft within the surface boundary layer. However, unmanned Aerial Vehicles (UAVs) can be operated safely to measure IN number concentration, Relative Humidity with respect to ice (RHi), T, horizontal wind speed (Uh) and direction, and ice crystal spectra less than about 500 micron. Thermodynamic profiling by a Radiometrics Profiling Microwave Radiometer (PMWR) and Vaisala CL51 ceilometer was used to describe ice fog conditions in the vertical and its time development. In this presentation, ice fog characteristics and its thermodynamic environment will be presented using both ground-based and airborne platforms such as a UAV with new sensors. Some examples of measurements from the UAV for future research, and challenges related to both ice fog measurements and visibility parameterization will also be presented.

  13. Road surveillance using a team of small UAVs

    NASA Astrophysics Data System (ADS)

    Kingston, Derek

    2009-05-01

    Monitoring roads is an important task for missions such as base security. This paper describes a road monitoring system composed of a team of small UAVs equipped with gimballed cameras. Given a fine description of the target road, algorithms for waypoint approximation, sensor steering, and UAV spacing are developed to allow N UAVs to survey stretches of road for activity. By automating the route generation and road tracking, human operators are freed to study the sensor returns from the vehicles to detect anomalous behavior. The spacing algorithm is robust to retasking and insertion/deletion of UAVs. Hardware results are presented that demonstrate the applicability of the solution.

  14. Adaptive information interactive mechanism for multi-UAV visual navigation

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Dai, Qionghai

    2012-06-01

    Multi-unmanned aerial vehicle (UAV) cooperative communication for visual navigation has recently generated significant concern. It has large amounts of visual information to be transmitted and processed among UAVs with realtime requirements. And the UAV clusters have self-organized, time-varying and high dynamic characteristics. Considering the above conditions, we propose an adaptive information interactive mechanism (AIIM) for multi-UAV visual navigation. In the mechanism, the function modules for UAV inter-communication interface are designed, the mobility-based link lifetime is established and the information interactive protocol is presented. Thus we combine the mobility of UAVs with the corresponding communication requirements to make effective information interaction for UAVs. Task-oriented distributed control is adopted to improve the collaboration flexibility in the multi-UAV visual navigation system. In order to timely obtain the necessary visual information, each UAV can cooperate with other relevant UAVs which meet some certain terms such as situation, task or environmental conditions. Simulation results are presented to show the validity of the proposed mechanism in terms of end-to-end delay and links stability.

  15. Assessing the Feasibility of Uav-Based LIDAR for High Resolution Forest Change Detection

    NASA Astrophysics Data System (ADS)

    Wallace, L. O.; Lucieer, A.; Watson, C. S.

    2012-08-01

    Airborne LiDAR data has become an important tool for both the scientific and industry based investigation of forest structure. The uses of discrete return observations have now reached a maturity level such that the operational use of this data is becoming increasingly common. However, due to the cost of data collection, temporal studies into forest change are often not feasible or completed at infrequent and at uneven intervals. To achieve high resolution temporal LiDAR surveys, this study has developed a micro-Unmanned Aerial Vehicle (UAV) equipped with a discrete return 4-layer LiDAR device and miniaturised positioning sensors. This UAV has been designed to be low-cost and to achieve maximum flying time. In order to achieve these objectives and overcome the accuracy restrictions presented by miniaturised sensors a novel processing strategy based on a Kalman smoother algorithm has been developed. This strategy includes the use of the structure from motion algorithm in estimating camera orientation, which is then used to restrain IMU drift. The feasibility of such a platform for monitoring forest change is shown by demonstrating that the pointing accuracy of this UAV LiDAR device is within the accuracy requirements set out by the Australian Intergovernmental Committee on Surveying and Mapping (ICSM) standards.

  16. Orientation and Calibration Requirements for Hyperpectral Imaging Using UAVs: a Case Study

    NASA Astrophysics Data System (ADS)

    Tommaselli, A. M. G.; Berveglieri, A.; Oliveira, R. A.; Nagai, L. Y.; Honkavaara, E.

    2016-03-01

    Flexible tools for photogrammetry and remote sensing using unmanned airborne vehicles (UAVs) have been attractive topics of research and development. The lightweight hyperspectral camera based on a Fabry-Pérot interferometer (FPI) is one of the highly interesting tools for UAV based remote sensing for environmental and agricultural applications. The camera used in this study acquires images from different wavelengths by changing the FPI gap and using two CMOS sensors. Due to the acquisition principle of this camera, the interior orientation parameters (IOP) of the spectral bands can vary for each band and sensor and changing the configuration also would change these sets of parameters posing an operational problem when several bands configurations are being used. The objective of this study is to assess the impact of use IOPs estimated for some bands in one configuration for other bands of different configuration the FPI camera, considering different IOP and EOP constraints. The experiments were performed with two FPI-hyperspectral camera data sets: the first were collected 3D terrestrial close-range calibration field and the second onboard of an UAV in a parking area in the interior of São Paulo State.

  17. Camera Calibration for Uav Application Using Sensor of Mobile Camera

    NASA Astrophysics Data System (ADS)

    Takahashi, Y.; Chikatsu, H.

    2015-05-01

    Recently, 3D measurements using small unmanned aerial vehicles (UAVs) have increased in Japan, because small type UAVs is easily available at low cost and the analysis software can be created the easily 3D models. However, small type UAVs have a problem: they have very short flight times and a small payload. In particular, as the payload of a small type UAV increases, its flight time decreases. Therefore, it is advantageous to use lightweight sensors in small type UAVs. A mobile camera is lightweight and has many sensors such as an accelerometer, a magnetic field, and a gyroscope. Moreover, these sensors can be used simultaneously. Therefore, the authors think that the problems of small UAVs can be solved using the mobile camera. The authors executed camera calibration using a test target for evaluating sensor values measured using a mobile camera. Consequently, the authors confirmed the same accuracy with normal camera calibration.

  18. Airborne change detection system for the detection of route mines

    NASA Astrophysics Data System (ADS)

    Donzelli, Thomas P.; Jackson, Larry; Yeshnik, Mark; Petty, Thomas E.

    2003-09-01

    The US Army is interested in technologies that will enable it to maintain the free flow of traffic along routes such as Main Supply Routes (MSRs). Mines emplaced in the road by enemy forces under cover of darkness represent a major threat to maintaining a rapid Operational Tempo (OPTEMPO) along such routes. One technique that shows promise for detecting enemy mining activity is Airborne Change Detection, which allows an operator to detect suspicious day-to-day changes in and around the road that may be indicative of enemy mining. This paper presents an Airborne Change Detection that is currently under development at the US Army Night Vision and Electronic Sensors Directorate (NVESD). The system has been tested using a longwave infrared (LWIR) sensor on a vertical take-off and landing unmanned aerial vehicle (VTOL UAV) and a midwave infrared (MWIR) sensor on a fixed wing aircraft. The system is described and results of the various tests conducted to date are presented.

  19. Real time UAV autonomy through offline calculations

    NASA Astrophysics Data System (ADS)

    Jung, Sunghun

    Two or three dimensional mission plans for a single or a group of hover or fixed wing UAVs are generated. The mission plans can largely be separated into seven main parts. Firstly, the Region Growing algorithm is used to generate a map from 2D or 3D images. Secondly, the map is analyzed to separate each blocks using vertices of blocks and seven filtering steps. Thirdly, the Trapezoidal map algorithm is used to convert the map into a traversability graph. Fourthly, this process also filters out paths that are not traversable. That is, nodes located inside the blocks and too closely located nodes are filtered out. Fifthly, the Dijkstra algorithm is used to calculate the shortest path from a starting point to a goal point. Sixthly, the 1D Optimal Control algorithm is applied to manipulate the velocity and acceleration of the UAVs efficiently. Basically, the UAVs accelerates at one graph node and maintains a constant velocity and decelerates before reaching the next graph node. Lastly, Traveling Salesman Problem Method (TSP) algorithm is used to calculate the shortest path to search the whole region. After this discretization of space and time, it becomes possible to solve several autonomous mission planning problems. We focus on one of the most difficult problems: coordinated search. This is a multiple Traveling Salesman Problem (mTSP). We solve it by decomposing the search region and solving TSPs for each vehicle searching a sub-region. The mTSP is generally used when there are more than one salesman is used. In addition to the four main parts, there are three minor parts which support the main parts. Firstly, Target Detection algorithm is generated to detect a target located near the UAVs' path. A picture of the desired target is inserted into the algorithm before UAVs launch. Using the Scale-Invariant Transform Feature (SIFT) algorithm, a target with a specific shape can be detected. Secondly, Tracking algorithm is generated to manipulate UAVs to follow targets

  20. Uav Photogrammetry with Oblique Images: First Analysis on Data Acquisition and Processing

    NASA Astrophysics Data System (ADS)

    Aicardi, I.; Chiabrando, F.; Grasso, N.; Lingua, A. M.; Noardo, F.; Spanò, A.

    2016-06-01

    In recent years, many studies revealed the advantages of using airborne oblique images for obtaining improved 3D city models (e.g. including façades and building footprints). Expensive airborne cameras, installed on traditional aerial platforms, usually acquired the data. The purpose of this paper is to evaluate the possibility of acquire and use oblique images for the 3D reconstruction of a historical building, obtained by UAV (Unmanned Aerial Vehicle) and traditional COTS (Commercial Off-the-Shelf) digital cameras (more compact and lighter than generally used devices), for the realization of high-level-of-detail architectural survey. The critical issues of the acquisitions from a common UAV (flight planning strategies, ground control points, check points distribution and measurement, etc.) are described. Another important considered aspect was the evaluation of the possibility to use such systems as low cost methods for obtaining complete information from an aerial point of view in case of emergency problems or, as in the present paper, in the cultural heritage application field. The data processing was realized using SfM-based approach for point cloud generation: different dense image-matching algorithms implemented in some commercial and open source software were tested. The achieved results are analysed and the discrepancies from some reference LiDAR data are computed for a final evaluation. The system was tested on the S. Maria Chapel, a part of the Novalesa Abbey (Italy).

  1. Enabling America's Next Generation of Aviation Vehicles

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Viewgraphs o America's Next Generation of Aviation Vehicles are presented. The topics include: 1) UAV's- Unlimited Applications; 2) Global Challenges; 3) UAV/CNS Overview; 4) Communications; 5) Navigation; and 6) Surveillance.

  2. Salient object detection approach in UAV video

    NASA Astrophysics Data System (ADS)

    Zhang, Yueqiang; Su, Ang; Zhu, Xianwei; Zhang, Xiaohu; Shang, Yang

    2013-10-01

    The automatic detection of visually salient information from abundant video imagery is crucial, as it plays an important role in surveillance and reconnaissance tasks for Unmanned Aerial Vehicle (UAV). A real-time approach for the detection of salient objects on road, e.g. stationary and moving vehicle or people, is proposed, which is based on region segmentation and saliency detection within related domains. Generally, the traditional method specifically depends upon additional scene information and auxiliary thermal or IR sensing for secondary confirmation. However, this proposed approach can detect the interesting objects directly from video imagery captured by optical camera fixed on the small level UAV platform. To validate this proposed salient object detection approach, the 25 Hz video data from our low speed small UAV are tested. The results have demonstrated the proposed approach performs excellently in isolated rural environments.

  3. Application of a Very-Low-Cost Unmanned Aerial Vehicle (UAV) and Consumer Grade Camera for the Collection of Research Grade Data: Preliminary Findings

    NASA Astrophysics Data System (ADS)

    Christian, P.; Davis, J. D.; Blesius, L.

    2013-12-01

    The use of UAV technology in the field of geoscience research has grown almost exponentially in the last decade. UAVs have been utilized as a sensor platform in many fields including geology, biology, climatology, geomorphology and archaeology. A UAV's ability to fly frequently, at very low altitude, and at relatively little cost makes them a perfect compromise between free, low temporal and spatial resolution satellite data and terrestrial based survey when there are insufficient funds to purchase custom satellite or manned aircraft data. Unfortunately, many available UAVs for research are still relatively expensive and often have predetermined imaging systems. However, the proliferation of hobbyist grade UAVs and consumer point and shoot cameras may provide many research projects with an alternative that is both cost-effective and efficient in data collection. This study therefore seeks to answer the question, can these very low cost, hobby-grade UAVs be used to produce research grade data. To achieve this end, in December of 2012 a small grant was obtained (<$6500) to set up a complete UAV system and to employ it in a diverse range of research. The system is comprised of a 3D Robotics hexacopter, Ardupilot automated flight hardware and software, spare parts and tool kit, two Canon point-and-shoot cameras including one modified for near infrared imagery, and a field laptop. To date, successful research flights have been flown for geomorphic research in degraded and restored montane meadows to study stream channel formation using both visible and near infrared imagery as well as for the creation of digital elevation models of large hillslope gullies using structure from motion (SFM). Other applications for the hexacopter, in progress or planned, include landslide monitoring, vegetation monitoring and mapping using the normalized difference vegetation index, archaeological survey, and bird nest identification on small rock islands. An analysis of the results

  4. UAV formation control design with obstacle avoidance in dynamic three-dimensional environment.

    PubMed

    Chang, Kai; Xia, Yuanqing; Huang, Kaoli

    2016-01-01

    This paper considers the artificial potential field method combined with rotational vectors for a general problem of multi-unmanned aerial vehicle (UAV) systems tracking a moving target in dynamic three-dimensional environment. An attractive potential field is generated between the leader and the target. It drives the leader to track the target based on the relative position of them. The other UAVs in the formation are controlled to follow the leader by the attractive control force. The repulsive force affects among the UAVs to avoid collisions and distribute the UAVs evenly on the spherical surface whose center is the leader-UAV. Specific orders or positions of the UAVs are not required. The trajectories of avoidance obstacle can be obtained through two kinds of potential field with rotation vectors. Every UAV can choose the optimal trajectory to avoid the obstacle and reconfigure the formation after passing the obstacle. Simulations study on UAV are presented to demonstrate the effectiveness of proposed method.

  5. Uav Onboard GPS in Positioning Determination

    NASA Astrophysics Data System (ADS)

    Tahar, K. N.; Kamarudin, S. S.

    2016-06-01

    The establishment of ground control points is a critical issue in mapping field, especially for large scale mapping. The fast and rapid technique for ground control point's establishment is very important for small budget projects. UAV onboard GPS has the ability to determine the point positioning. The objective of this research is to assess the accuracy of unmanned aerial vehicle onboard global positioning system in positioning determination. Therefore, this research used UAV onboard GPS as an alternative to determine the point positioning at the selected area. UAV is one of the powerful tools for data acquisition and it is used in many applications all over the world. This research concentrates on the error contributed from the UAV onboard GPS during observation. There are several points that have been used to study the pattern of positioning error. All errors were analyzed in world geodetic system 84- coordinate system, which is the basic coordinate system used by the global positioning system. Based on this research, the result of UAV onboard GPS positioning could be used in ground control point establishment with the specific error. In conclusion, accurate GCP establishment could be achieved using UAV onboard GPS by applying a specific correction based on this research.

  6. Nano-based chemical sensor array systems for uninhabited ground and airborne vehicles

    NASA Astrophysics Data System (ADS)

    Brantley, Christina; Ruffin, Paul B.; Edwards, Eugene

    2009-03-01

    In a time when homemade explosive devices are being used against soldiers and in the homeland security environment, it is becoming increasingly evident that there is an urgent need for high-tech chemical sensor packages to be mounted aboard ground and air vehicles to aid soldiers in determining the location of explosive devices and the origin of bio-chemical warfare agents associated with terrorist activities from a safe distance. Current technologies utilize relatively large handheld detection systems that are housed on sizeable robotic vehicles. Research and development efforts are underway at the Army Aviation & Missile Research, Development, and Engineering Center (AMRDEC) to develop novel and less expensive nano-based chemical sensors for detecting explosives and chemical agents used against the soldier. More specifically, an array of chemical sensors integrated with an electronics control module on a flexible substrate that can conform to and be surface-mounted to manned or unmanned vehicles to detect harmful species from bio-chemical warfare and other explosive devices is being developed. The sensor system under development is a voltammetry-based sensor system capable of aiding in the detection of any chemical agent and in the optimization of sensor microarray geometry to provide nonlinear Fourier algorithms to characterize target area background (e.g., footprint areas). The status of the research project is reviewed in this paper. Critical technical challenges associated with achieving system cost, size, and performance requirements are discussed. The results obtained from field tests using an unmanned remote controlled vehicle that houses a CO2/chemical sensor, which detects harmful chemical agents and wirelessly transmits warning signals back to the warfighter, are presented. Finally, the technical barriers associated with employing the sensor array system aboard small air vehicles will be discussed.

  7. Preservation potential of subtle glacial landforms based on detailed mapping of recently exposed proglacial areas: application of unmanned aerial vehicle (UAV) and structure-from-motion (SfM)

    NASA Astrophysics Data System (ADS)

    Ewertowski, Marek; Evans, David; Roberts, David; Tomczyk, Aleksandra; Ewertowski, Wojciech

    2016-04-01

    Ongoing glacier retreat results in the continuous exposure of proglacial areas. Such areas contain invaluable information about glacial process-form relationships manifest in specific landform assemblages. However, preservation potential of freshly exposed glacial landforms is very low, as proglacial terrains are one of the most dynamic parts of the landscape. Therefore, rapid mapping and geomorphological characterisation of such areas is important from a glaciological and geomorphological point of view for proper understanding and reconstruction of glacier-landform dynamics and chronology of glacial events. Annual patterns of recession and relatively small areas exposed every year, mean that the performing of regular aerial or satellite survey is expensive and therefore impractical. Recent advances in technology enables the development of low-cost alternatives for traditional aerial surveys. Small unmanned aerial vehicles (UAV) can be used to acquire high-resolution (several cm) low-altitude photographs. The UAV-based photographs can be subsequently processed through the structure-from-motion process to generate detailed orthophotomaps and digital elevation models. In this study we present case studies from the forelands of various glaciers on Iceland and Svalbard representing different types of proglacial landscapes: Fláajökull (annual push moraines); Hofellsjökul (bedrock bedforms and push moraines); Fjallsjökull (marginal drainage network); Rieperbreen (crevasse squeeze ridges and longitudinal debris stripes); Ayerbreen (transverse debris ridges); Foxfonna (longitudinal debris stripes);Hørbyebreen (geometric ridge network); Nordenskiöldbreen (fluted till surface); Ebbabreen (controlled moraine complex). UAV campaigns were conducted using a low-cost quadcopter platform. Resultant orthophotos and DEMs enabled mapping and assessment of recent glacial landscape development in different types of glacial landsystems. Results of our study indicate that

  8. Classical Photogrammetry and Uav - Selected Ascpects

    NASA Astrophysics Data System (ADS)

    Mikrut, S.

    2016-06-01

    The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical) height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km2) for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle). Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy). After initial pre-processing of data, the images were put together, and shown side by side

  9. AVIATR—Aerial Vehicle for In-situ and Airborne Titan Reconnaissance. A Titan airplane mission concept

    NASA Astrophysics Data System (ADS)

    Barnes, Jason W.; Lemke, Lawrence; Foch, Rick; McKay, Christopher P.; Beyer, Ross A.; Radebaugh, Jani; Atkinson, David H.; Lorenz, Ralph D.; Le Mouélic, Stéphane; Rodriguez, Sebastien; Gundlach, Jay; Giannini, Francesco; Bain, Sean; Flasar, F. Michael; Hurford, Terry; Anderson, Carrie M.; Merrison, Jon; Ádámkovics, Máté; Kattenhorn, Simon A.; Mitchell, Jonathan; Burr, Devon M.; Colaprete, Anthony; Schaller, Emily; Friedson, A. James; Edgett, Kenneth S.; Coradini, Angioletta; Adriani, Alberto; Sayanagi, Kunio M.; Malaska, Michael J.; Morabito, David; Reh, Kim

    2012-03-01

    We describe a mission concept for a stand-alone Titan airplane mission: Aerial Vehicle for In-situ and Airborne Titan Reconnaissance (AVIATR). With independent delivery and direct-to-Earth communications, AVIATR could contribute to Titan science either alone or as part of a sustained Titan Exploration Program. As a focused mission, AVIATR as we have envisioned it would concentrate on the science that an airplane can do best: exploration of Titan's global diversity. We focus on surface geology/hydrology and lower-atmospheric structure and dynamics. With a carefully chosen set of seven instruments—2 near-IR cameras, 1 near-IR spectrometer, a RADAR altimeter, an atmospheric structure suite, a haze sensor, and a raindrop detector—AVIATR could accomplish a significant subset of the scientific objectives of the aerial element of flagship studies. The AVIATR spacecraft stack is composed of a Space Vehicle (SV) for cruise, an Entry Vehicle (EV) for entry and descent, and the Air Vehicle (AV) to fly in Titan's atmosphere. Using an Earth-Jupiter gravity assist trajectory delivers the spacecraft to Titan in 7.5 years, after which the AVIATR AV would operate for a 1-Earth-year nominal mission. We propose a novel `gravity battery' climb-then-glide strategy to store energy for optimal use during telecommunications sessions. We would optimize our science by using the flexibility of the airplane platform, generating context data and stereo pairs by flying and banking the AV instead of using gimbaled cameras. AVIATR would climb up to 14 km altitude and descend down to 3.5 km altitude once per Earth day, allowing for repeated atmospheric structure and wind measurements all over the globe. An initial Team-X run at JPL priced the AVIATR mission at FY10 715M based on the rules stipulated in the recent Discovery announcement of opportunity. Hence we find that a standalone Titan airplane mission can achieve important science building on Cassini's discoveries and can likely do so

  10. Insights and recommendations of use of UAV platforms in precision agriculture in Brazil

    NASA Astrophysics Data System (ADS)

    Jorge, Lúcio A. C.; Brandão, Ziany N.; Inamasu, Ricardo Y.

    2014-10-01

    The Interest in Unmanned Aerial Vehicles (UAVs) has grown around the world and several efforts are underway to integrate UAV operations routinely and safely into remote sensing applications, specially applied in precision agriculture. Reviewing the use of UAV in agriculture it shows limitations and opportunities. So the challenges of UAV platforms for remote sensing and precision agriculture were identified during a real case studied at a citrus area to monitor the HLB (Huanglongbing) infestation. Recommended actions for moving forward were identified and showed that is possible to use UAVs for detection of crop diseases with high precision.

  11. Structurally Integrated Antenna Concepts for HALE UAVs

    NASA Technical Reports Server (NTRS)

    Cravey, Robin L.; Vedeler, Erik; Goins, Larry; Young, W. Robert; Lawrence, Roland W.

    2006-01-01

    This technical memorandum describes work done in support of the Multifunctional Structures and Materials Team under the Vehicle Systems Program's ITAS (Integrated Tailored Aero Structures) Project during FY 2005. The Electromagnetics and Sensors Branch (ESB) developed three ultra lightweight antenna concepts compatible with HALE UAVs (High Altitude Long Endurance Unmanned Aerial Vehicles). ESB also developed antenna elements that minimize the interaction between elements and the vehicle to minimize the impact of wing flexure on the EM (electromagnetic) performance of the integrated array. In addition, computer models were developed to perform phase correction for antenna arrays whose elements are moving relative to each other due to wing deformations expected in HALE vehicle concepts. Development of lightweight, conformal or structurally integrated antenna elements and compensating for the impact of a lightweight, flexible structure on a large antenna array are important steps in the realization of HALE UAVs for microwave applications such as passive remote sensing and communications.

  12. Design of an airborne launch vehicle for an air launched space booster

    NASA Astrophysics Data System (ADS)

    Chao, Chin; Choi, Rich; Cohen, Scott; Dumont, Brian; Gibin, Mauricius; Jorden, Rob; Poth, Stefan

    1993-12-01

    A conceptual design is presented for a carrier vehicle for an air launched space booster. This airplane is capable of carrying a 500,000 pound satellite launch system to an altitude over 40,000 feet for launch. The airplane features a twin fuselage configuration for improved payload and landing gear integration, a high aspect ratio wing for maneuverability at altitude, and is powered by six General Electric GE-90 engines. The analysis methods used and the systems employed in the airplane are discussed. Launch costs are expected to be competitive with existing launch systems.

  13. Design of an airborne launch vehicle for an air launched space booster

    NASA Technical Reports Server (NTRS)

    Chao, Chin; Choi, Rich; Cohen, Scott; Dumont, Brian; Gibin, Mauricius; Jorden, Rob; Poth, Stefan

    1993-01-01

    A conceptual design is presented for a carrier vehicle for an air launched space booster. This airplane is capable of carrying a 500,000 pound satellite launch system to an altitude over 40,000 feet for launch. The airplane features a twin fuselage configuration for improved payload and landing gear integration, a high aspect ratio wing for maneuverability at altitude, and is powered by six General Electric GE-90 engines. The analysis methods used and the systems employed in the airplane are discussed. Launch costs are expected to be competitive with existing launch systems.

  14. HTS machines as enabling technology for all-electric airborne vehicles

    NASA Astrophysics Data System (ADS)

    Masson, P. J.; Brown, G. V.; Soban, D. S.; Luongo, C. A.

    2007-08-01

    Environmental protection has now become paramount as evidence mounts to support the thesis of human activity-driven global warming. A global reduction of the emissions of pollutants into the atmosphere is therefore needed and new technologies have to be considered. A large part of the emissions come from transportation vehicles, including cars, trucks and airplanes, due to the nature of their combustion-based propulsion systems. Our team has been working for several years on the development of high power density superconducting motors for aircraft propulsion and fuel cell based power systems for aircraft. This paper investigates the feasibility of all-electric aircraft based on currently available technology. Electric propulsion would require the development of high power density electric propulsion motors, generators, power management and distribution systems. The requirements in terms of weight and volume of these components cannot be achieved with conventional technologies; however, the use of superconductors associated with hydrogen-based power plants makes possible the design of a reasonably light power system and would therefore enable the development of all-electric aero-vehicles. A system sizing has been performed both for actuators and for primary propulsion. Many advantages would come from electrical propulsion such as better controllability of the propulsion, higher efficiency, higher availability and less maintenance needs. Superconducting machines may very well be the enabling technology for all-electric aircraft development.

  15. UAVs Being Used for Environmental Surveying

    ScienceCinema

    Chung, Sandra

    2016-07-12

    e Arcturus unmanned aerial vehicles, or UAVs, are much more sophisticated than your typical remote-controlled plane. INL robotics and remote sensing experts have added state-of-the-art imaging and wireless technology to the UAVs to create intelligent remote surveillance craft that can rapidly survey a wide area for damage and track down security threats. But these robot planes aren't just for security anymore. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

  16. Common Operating Picture: UAV Security Study

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This initial communication security study is a top-level assessment of basic security issues related to the operation of Unmanned Aerial Vehicles (UAVs) in the National Airspace System (NAS). Security considerations will include information relating to the use of International Civil Aviation Organization (ICAO) Aeronautical Telecommunications Network (ATN) protocols and applications identifying their maturity, as well as the use of IPV4 and a version of mobile IPV6. The purpose of this assessment is to provide an initial analysis of the security implications of introducing UAVs into the NAS.

  17. UAVs Being Used for Environmental Surveying

    SciTech Connect

    Chung, Sandra

    2010-01-01

    e Arcturus unmanned aerial vehicles, or UAVs, are much more sophisticated than your typical remote-controlled plane. INL robotics and remote sensing experts have added state-of-the-art imaging and wireless technology to the UAVs to create intelligent remote surveillance craft that can rapidly survey a wide area for damage and track down security threats. But these robot planes aren't just for security anymore. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

  18. Geophex Airborne Unmanned Survey System (GAUSS). Topical report, October 1993--September 1996

    SciTech Connect

    1998-12-31

    This document is a Final Technical Report that describes the results of the Geophex Airborne Unmanned Survey System (GAUSS) research project. The objectives were to construct a geophysical data acquisition system that uses a remotely operated unmanned aerial vehicle (UAV) and to evaluate its effectiveness for characterization of hazardous environmental sites. The GAUSS is a data acquisition system that mitigates the potential risk to personnel during geophysical characterization of hazardous or radioactive sites. The fundamental basis of the GAUSS is as follows: (1) an unmanned survey vehicle carries geophysical sensors into a hazardous location, (2) the pilot remains outside the hazardous site and operates the vehicle using radio control, (3) geophysical measurements and their spatial locations are processed by an automated data-acquisition system which displays data on an off-site monitor in real-time, and (4) the pilot uses the display to direct the survey vehicle for complete site coverage. The objective of our Phase I research was to develop a data acquisition and processing (DAP) subsystem and geophysical sensors suitable for UAV deployment. We integrated these two subsystems to produce an automated, hand-held geophysical surveying system. The objective of the Phase II effort was to modify the subsystems and integrate them into an airborne prototype. The completed GAUSS DAP system consists of a UAV platform, a laser tracking and ranging subsystem, a telemetry subsystem, light-weight geophysical sensors, a base-station computer (BC), and custom-written survey control software (SCS). We have utilized off-the-shelf commercial products, where possible, to reduce cost and design time.

  19. Techniques of UAV system land use changes detection application

    NASA Astrophysics Data System (ADS)

    Zhang, Youying; Cui, Hongxia

    2011-02-01

    The unmanned aerial vehicle( UAV) was able to acquire remote sensing images with low cost, precise and high spatial resolution information needed by management of Land use at desired time. The aim of this paper was to present an overview of the ongoing research on the potential and techniques of low-altitude UAV system for land use applications. The development of crucial subsystems consisting of the UAV platforms, multiple camera system, camera calibration and photogrammetric production, was introduced together. A procedure of images acquisition and photogrammetric processing was proposed. To detect land use changes, methods based on DSMs and DLG were discussed and adopted in this paper. Finally, analysis of land use research based UAVs was realized on real flight experiments of two study areas. The results of this study show that UAVs can be used successfully for land use change detection.

  20. UAVs for Glacier Mapping: Lessons Learned

    NASA Astrophysics Data System (ADS)

    McKinnon, T.; McKinnon, K. A.; Anderson, B.

    2014-12-01

    Using two different unmanned aerial vehicles (UAVs) mounted with cameras, we created a digital elevation model (DEM) of the lower 12 km^2 of Tasman Glacier, South Island, New Zealand in March 2014. The project served primarily as a proof-of-concept, and here we discuss the lessons learned, emphasizing the practical, logistical, and flight issues. We tested two different fixed-wing airframes -- a twin-boom tradition and flying wing; two different camera types, both consumer-grade RGB; and various combinations of RC and telemetry radios. We used both commercial and open-source photogrammetry software to create the mosaic and DEM imagery. Some of the most critical UAV-specific issues are: access to a launch/landing site, adequate landing zones, range, airspace contention with manned aircraft, and hardware reliability. While UAVs provide a lower-cost method for photogrammetry access, it also comes with a unique set of challenges.

  1. Airborne Hyperspectral Imaging of Seagrass and Coral Reef

    NASA Astrophysics Data System (ADS)

    Merrill, J.; Pan, Z.; Mewes, T.; Herwitz, S.

    2013-12-01

    This talk presents the process of project preparation, airborne data collection, data pre-processing and comparative analysis of a series of airborne hyperspectral projects focused on the mapping of seagrass and coral reef communities in the Florida Keys. As part of a series of large collaborative projects funded by the NASA ROSES program and the Florida Fish and Wildlife Conservation Commission and administered by the NASA UAV Collaborative, a series of airborne hyperspectral datasets were collected over six sites in the Florida Keys in May 2012, October 2012 and May 2013 by Galileo Group, Inc. using a manned Cessna 172 and NASA's SIERRA Unmanned Aerial Vehicle. Precise solar and tidal data were used to calculate airborne collection parameters and develop flight plans designed to optimize data quality. Two independent Visible and Near-Infrared (VNIR) hyperspectral imaging systems covering 400-100nm were used to collect imagery over six Areas of Interest (AOIs). Multiple collections were performed over all sites across strict solar windows in the mornings and afternoons. Independently developed pre-processing algorithms were employed to radiometrically correct, synchronize and georectify individual flight lines which were then combined into color balanced mosaics for each Area of Interest. The use of two different hyperspectral sensor as well as environmental variations between each collection allow for the comparative analysis of data quality as well as the iterative refinement of flight planning and collection parameters.

  2. Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing.

    PubMed

    Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan

    2015-07-17

    To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system.

  3. UAV Photogrammetry Implementation to Enhance Land Surveying, Comparisons and Possibilities

    NASA Astrophysics Data System (ADS)

    El Meouche, R.; Hijazi, I.; Poncet, P. A.; Abunemeh, M.; Rezoug, M.

    2016-10-01

    The use of Unmanned Aerial Vehicles (UAVs) for surveying is now widespread and operational for several applications - quarry monitoring, archeological site surveys, forest management and 3D modeling for buildings, for instance. UAV is increasingly used by land surveyors especially for those kinds of projects. It is still ambiguous whether UAV can be applicable for smaller sites and property division. Therefore, the objective of this research is to extract a vectorized plan utilizing a UAV for a small site and investigate the possibility of an official land surveyor exploiting and certificating it. To do that, two plans were created, one using a UAV and another utilizing classical land surveyor instruments (Total Station). A comparison was conducted between the two plans to evaluate the accuracy of the UAV technique compared to the classical one. Moreover, other parameters were also considered such as execution time and the surface covered. The main problems associated with using a UAV are the level of precision and the visualization of the whole area. The results indicated that the precision is quite satisfactory with a maximum error of 1.0 cm on ground control points, and 4 cm for the rest of the model. On the other hand, the results showed that it is not possible to represent the whole area of interest utilizing a UAV, due to vegetation.

  4. Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing

    PubMed Central

    Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan

    2015-01-01

    To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system. PMID:26193281

  5. New approaches to the development and employment of the UAV

    NASA Astrophysics Data System (ADS)

    Pikner, Ivo

    2012-11-01

    The article is dealing with the future of the Unmanned Aerial Vehicles (UAVs), shows the current trends and characterizes the major tendency for future operational employment of the UAVs. The UAVs proved their technical feasibility, military applicability and operational value. Focal point of activities of the UAVs, until recently, consisted in performing the tasks aimed to gathering the important information for the planning process support. Reconnaissance UAVs can perform their missions both by day and by night, practically at any weather conditions on the range according to the command level. Combat UAVs, on top of that, are capable perform their missions against ground targets by jamming or to destroy them. Analyses of trends of operational employment of UAVs show to new possibilities for introduction of new types of UAVs (miniaturization) to armed forces structures. These new means will play the decisive role not only in the preparatory phases but also during the crisis situations resolution process. This article is part of the "Operational Concepts of the Armed Forms of the Czech Republic in Joint Operations", a defence research project that is being solved at the University of Defence in Brno (CZ).

  6. Formation Flight of Multiple UAVs via Onboard Sensor Information Sharing.

    PubMed

    Park, Chulwoo; Cho, Namhoon; Lee, Kyunghyun; Kim, Youdan

    2015-01-01

    To monitor large areas or simultaneously measure multiple points, multiple unmanned aerial vehicles (UAVs) must be flown in formation. To perform such flights, sensor information generated by each UAV should be shared via communications. Although a variety of studies have focused on the algorithms for formation flight, these studies have mainly demonstrated the performance of formation flight using numerical simulations or ground robots, which do not reflect the dynamic characteristics of UAVs. In this study, an onboard sensor information sharing system and formation flight algorithms for multiple UAVs are proposed. The communication delays of radiofrequency (RF) telemetry are analyzed to enable the implementation of the onboard sensor information sharing system. Using the sensor information sharing, the formation guidance law for multiple UAVs, which includes both a circular and close formation, is designed. The hardware system, which includes avionics and an airframe, is constructed for the proposed multi-UAV platform. A numerical simulation is performed to demonstrate the performance of the formation flight guidance and control system for multiple UAVs. Finally, a flight test is conducted to verify the proposed algorithm for the multi-UAV system. PMID:26193281

  7. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition.

    PubMed

    McEvoy, John F; Hall, Graham P; McDonald, Paul G

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys.

  8. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition

    PubMed Central

    Hall, Graham P.; McDonald, Paul G.

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys. PMID:27020132

  9. Detection of surface elevation changes using an unmanned aerial vehicle on the debris-free Storbreen glacier in Norway

    NASA Astrophysics Data System (ADS)

    Kraaijenbrink, Philip; Andreassen, Liss; Immerzeel, Walter

    2016-04-01

    Recent studies have shown that the application of unmanned aerial vehicles (UAVs) has great potential to investigate the dynamic behavior of glaciers. The studies have successfully deployed UAVs over generally contrast-rich surfaces of debris-covered glaciers and highly crevassed bare ice glaciers. In this study, the potential of UAVs in glaciology is further exploited, as we use a fixed-wing UAV over the largely snow-covered Storbreen glacier in Norway in September 2015. The acquired UAV-imagery was processed into accurate digital elevation models and image mosaics using a Structure from Motion workflow. Georeferencing of the data was obtained by ingesting ground control points into the workflow that were accurately measured with a differential global navigation satellite system (DGNSS). Geodetic accuracy was determined by comparison with DGNSS surface profiles and stake positions that were measured on the same day. The processed data were compared with a LIDAR survey and airborne imagery acquisition from September and October 2009 to examine mass loss patterns and glacier retreat. Results show that the UAV is capable of producing high-quality elevation models and image mosaics for the low-contrast snow-covered Storbreen at unprecedented detail. The accuracy of the output product is lower when compared to contrast-rich debris-covered glaciers, but still considerably more accurate than spaceborne data products. Comparison with LIDAR data shows a spatially heterogeneous downwasting pattern of about 0.75 m a-1 over 2009-2015 for the upper part of Storbreen. The lower part exhibits considerably more downwasting in the range of 0.9-2.1 m a-1. We conclude that UAVs can be valuable for surveys of snow-covered glaciers to provide sufficient accurate elevation models and image mosaics, and we recommend the use of UAVs for the routine monitoring of benchmark glaciers such as Storbreen.

  10. Detection of surface elevation changes using an unmanned aerial vehicle on the debris-free Storbreen glacier in Norway

    NASA Astrophysics Data System (ADS)

    Kraaijenbrink, Philip; Andreassen, Liss; Immerzeel, Walter

    2016-04-01

    Recent studies have shown that the application of unmanned aerial vehicles (UAVs) has great potential to investigate the dynamic behavior of glaciers. The studies have successfully deployed UAVs over generally contrast-rich surfaces of debris-covered glaciers and highly crevassed bare ice glaciers. In this study, the potential of UAVs in glaciology is further exploited, as we use a fixed-wing UAV over the largely snow-covered Storbreen glacier in Norway in September 2015. The acquired UAV-imagery was processed into accurate digital elevation models and image mosaics using a Structure from Motion workflow. Georeferencing of the data was obtained by ingesting ground control points into the workflow that were accurately measured with a differential global navigation satellite system (DGNSS). Geodetic accuracy was determined by comparison with DGNSS surface profiles and stake positions that were measured on the same day. The processed data were compared with a LIDAR survey and airborne imagery acquisition from September and October 2009 to examine mass loss patterns and glacier retreat. Results show that the UAV is capable of producing high-quality elevation models and image mosaics for the low-contrast snow-covered Storbreen at unprecedented detail. The accuracy of the output product is lower when compared to contrast-rich debris-covered glaciers, but still considerably more accurate than spaceborne data products. Comparison with LIDAR data shows a spatially heterogeneous downwasting pattern of about 0.75 m a‑1 over 2009-2015 for the upper part of Storbreen. The lower part exhibits considerably more downwasting in the range of 0.9-2.1 m a‑1. We conclude that UAVs can be valuable for surveys of snow-covered glaciers to provide sufficient accurate elevation models and image mosaics, and we recommend the use of UAVs for the routine monitoring of benchmark glaciers such as Storbreen.

  11. Evaluation of unmanned aerial vehicle shape, flight path and camera type for waterfowl surveys: disturbance effects and species recognition.

    PubMed

    McEvoy, John F; Hall, Graham P; McDonald, Paul G

    2016-01-01

    The use of unmanned aerial vehicles (UAVs) for ecological research has grown rapidly in recent years, but few studies have assessed the disturbance impacts of these tools on focal subjects, particularly when observing easily disturbed species such as waterfowl. In this study we assessed the level of disturbance that a range of UAV shapes and sizes had on free-living, non-breeding waterfowl surveyed in two sites in eastern Australia between March and May 2015, as well as the capability of airborne digital imaging systems to provide adequate resolution for unambiguous species identification of these taxa. We found little or no obvious disturbance effects on wild, mixed-species flocks of waterfowl when UAVs were flown at least 60m above the water level (fixed wing models) or 40m above individuals (multirotor models). Disturbance in the form of swimming away from the UAV through to leaving the water surface and flying away from the UAV was visible at lower altitudes and when fixed-wing UAVs either approached subjects directly or rapidly changed altitude and/or direction near animals. Using tangential approach flight paths that did not cause disturbance, commercially available onboard optical equipment was able to capture images of sufficient quality to identify waterfowl and even much smaller taxa such as swallows. Our results show that with proper planning of take-off and landing sites, flight paths and careful UAV model selection, UAVs can provide an excellent tool for accurately surveying wild waterfowl populations and provide archival data with fewer logistical issues than traditional methods such as manned aerial surveys. PMID:27020132

  12. Characteristic analysis on UAV-MIMO channel based on normalized correlation matrix.

    PubMed

    Gao, Xi jun; Chen, Zi li; Hu, Yong Jiang

    2014-01-01

    Based on the three-dimensional GBSBCM (geometrically based double bounce cylinder model) channel model of MIMO for unmanned aerial vehicle (UAV), the simple form of UAV space-time-frequency channel correlation function which includes the LOS, SPE, and DIF components is presented. By the methods of channel matrix decomposition and coefficient normalization, the analytic formula of UAV-MIMO normalized correlation matrix is deduced. This formula can be used directly to analyze the condition number of UAV-MIMO channel matrix, the channel capacity, and other characteristic parameters. The simulation results show that this channel correlation matrix can be applied to describe the changes of UAV-MIMO channel characteristics under different parameter settings comprehensively. This analysis method provides a theoretical basis for improving the transmission performance of UAV-MIMO channel. The development of MIMO technology shows practical application value in the field of UAV communication.

  13. UAV photogrammetry for topographic monitoring of coastal areas

    NASA Astrophysics Data System (ADS)

    Gonçalves, J. A.; Henriques, R.

    2015-06-01

    Coastal areas suffer degradation due to the action of the sea and other natural and human-induced causes. Topographical changes in beaches and sand dunes need to be assessed, both after severe events and on a regular basis, to build models that can predict the evolution of these natural environments. This is an important application for airborne LIDAR, and conventional photogrammetry is also being used for regular monitoring programs of sensitive coastal areas. This paper analyses the use of unmanned aerial vehicles (UAV) to map and monitor sand dunes and beaches. A very light plane (SwingletCam) equipped with a very cheap, non-metric camera was used to acquire images with ground resolutions better than 5 cm. The Agisoft Photoscan software was used to orientate the images, extract point clouds, build a digital surface model and produce orthoimage mosaics. The processing, which includes automatic aerial triangulation with camera calibration and subsequent model generation, was mostly automated. To achieve the best positional accuracy for the whole process, signalised ground control points were surveyed with a differential GPS receiver. Two very sensitive test areas on the Portuguese northwest coast were analysed. Detailed DSMs were obtained with 10 cm grid spacing and vertical accuracy (RMS) ranging from 3.5 to 5.0 cm, which is very similar to the image ground resolution (3.2-4.5 cm). Where possible to assess, the planimetric accuracy of the orthoimage mosaics was found to be subpixel. Within the regular coastal monitoring programme being carried out in the region, UAVs can replace many of the conventional flights, with considerable gains in the cost of the data acquisition and without any loss in the quality of topographic and aerial imagery data.

  14. The Potential of Light Laser Scanners Developed for Unmanned Aerial Vehicles - The Review and Accuracy

    NASA Astrophysics Data System (ADS)

    Pilarska, M.; Ostrowski, W.; Bakuła, K.; Górski, K.; Kurczyński, Z.

    2016-10-01

    Modern photogrammetry and remote sensing have found small Unmanned Aerial Vehicles (UAVs) to be a valuable source of data in various branches of science and industry (e.g., agriculture, cultural heritage). Recently, the growing role of laser scanning in the application of UAVs has also been observed. Laser scanners dedicated to UAVs consist of four basic components: a laser scanner (LiDAR), an Inertial Measurement Unit (IMU), a Global Navigation Satellite System (GNSS) receiver and an on-board computer. The producers of the system provide users with detailed descriptions of the accuracies separately for each component. However, the final measurement accuracy is not given. This paper reviews state-of-the-art of laser scanners developed specifically for use on a UAV, presenting an overview of several constructions that are available nowadays. The second part of the paper is focussed on analysing the influence of the sensor accuracies on the final measurement accuracy. Mathematical models developed for Airborne Laser Scanning (ALS) accuracy analyses are used to estimate the theoretical accuracies of different scanners with conditions typical for UAV missions. Finally, the theoretical results derived from the mathematical simulations are compared with an experimental use case.

  15. Using an Unmanned Arial Vehicle (UAV) and a thermal infrared camera to estimate temperature differences on a lake surface, revealing incoming groundwater seepage.

    NASA Astrophysics Data System (ADS)

    Hoffmann, Helene; Müller, Sascha; Friborg, Thomas

    2014-05-01

    UAVs are at the budding stage of becoming efficient tools in geosciences due to their fast coverage of large areas, creating opportunities to collect comprehensive amounts of spatially distributed data. In this survey a fixed-wing UAV is equipped with a thermal infrared camera (Optris PI 450) conducting spatially distributed measurements of radiometric surface temperature, from a small groundwater-fed lake. We hypothesis that larger temperature differences in the lake surface will reveal locations of incoming groundwater seepage. During wintertime, warmer groundwater will have great incentive to rise to the lake surface without significant mixing with colder lake water and hence enable detection of incoming groundwater seepage with surface measurements. The investigated area is a 300x150 m section of Lake Vaeng in southern Jutland, Denmark. Detecting areas of groundwater seepage into lakes and quantifying these fluxes are of great importance not only for water budgets but also in relation to lake environments. Incoming groundwater might be a large nutrient source in lakes. GPS coordinates from the UAV are correlated with each thermal image based on UTC time stamps. Geo-reference is further improved with ground control points in the form of 0.2x0.2 m aluminum foil rectangles. Aluminum stands out clearly in thermal images and using seven of these ground control points, evenly distributed in the investigated area, led to an accuracy of 0.3 m. Using the Structure from Motion photogrammetric technique, a point cloud model is produced and camera positions along with intrinsic and extrinsic properties are established. Distinct temperature differences of 1.5 C have been detected along the south-eastern shore of Lake Vaeng. The location of these hotspots is in agreement with temperature differences measured with Distributed Temperature Sensing (DTS) system - indicating zones of groundwater seepage into the lake. In addition to faster execution of large spatially distributed

  16. Introducing a Low-Cost Mini-Uav for - and Multispectral-Imaging

    NASA Astrophysics Data System (ADS)

    Bendig, J.; Bolten, A.; Bareth, G.

    2012-07-01

    The trend to minimize electronic devices also accounts for Unmanned Airborne Vehicles (UAVs) as well as for sensor technologies and imaging devices. Consequently, it is not surprising that UAVs are already part of our daily life and the current pace of development will increase civil applications. A well known and already wide spread example is the so called flying video game based on Parrot's AR.Drone which is remotely controlled by an iPod, iPhone, or iPad (http://ardrone.parrot.com). The latter can be considered as a low-weight and low-cost Mini-UAV. In this contribution a Mini-UAV is considered to weigh less than 5 kg and is being able to carry 0.2 kg to 1.5 kg of sensor payload. While up to now Mini-UAVs like Parrot's AR.Drone are mainly equipped with RGB cameras for videotaping or imaging, the development of such carriage systems clearly also goes to multi-sensor platforms like the ones introduced for larger UAVs (5 to 20 kg) by Jaakkolla et al. (2010) for forestry applications or by Berni et al. (2009) for agricultural applications. The problem when designing a Mini-UAV for multi-sensor imaging is the limitation of payload of up to 1.5 kg and a total weight of the whole system below 5 kg. Consequently, the Mini-UAV without sensors but including navigation system and GPS sensors must weigh less than 3.5 kg. A Mini-UAV system with these characteristics is HiSystems' MK-Okto (www.mikrokopter.de). Total weight including battery without sensors is less than 2.5 kg. Payload of a MK-Okto is approx. 1 kg and maximum speed is around 30 km/h. The MK-Okto can be operated up to a wind speed of less than 19 km/h which corresponds to Beaufort scale number 3 for wind speed. In our study, the MK-Okto is equipped with a handheld low-weight NEC F30IS thermal imaging system. The F30IS which was developed for veterinary applications, covers 8 to 13 μm, weighs only 300 g

  17. Toward a General Nonlinear Model of Reduced Scale UAVs

    NASA Astrophysics Data System (ADS)

    Chriette, A.; Cheviron, T.; Plestan, F.

    2009-03-01

    This paper proposes, through a survey of models of several UAV-Structures, a generic nonlinear model for reduced scale aerial robotic vehicles (6 DOF)*. Dynamics of an aircraft and some VTOL UAV (quadricopter, ducted fan and classical helicopter) are illustrated. This generic model focuses only on the key physical efforts acting on the dynamics in order to be sufficiently simple to design a controller. The Small Body Forces expression which can introduce a zero dynamics is then discussed.

  18. An UAV scheduling and planning method for post-disaster survey

    NASA Astrophysics Data System (ADS)

    Li, G. Q.; Zhou, X. G.; Yin, J.; Xiao, Q. Y.

    2014-11-01

    Annually, the extreme climate and special geological environments lead to frequent natural disasters, e.g., earthquakes, floods, etc. The disasters often bring serious casualties and enormous economic losses. Post-disaster surveying is very important for disaster relief and assessment. As the Unmanned Aerial Vehicle (UAV) remote sensing with the advantage of high efficiency, high precision, high flexibility, and low cost, it is widely used in emergency surveying in recent years. As the UAVs used in emergency surveying cannot stop and wait for the happening of the disaster, when the disaster happens the UAVs usually are working at everywhere. In order to improve the emergency surveying efficiency, it is needed to track the UAVs and assign the emergency surveying task for each selected UAV. Therefore, a UAV tracking and scheduling method for post-disaster survey is presented in this paper. In this method, Global Positioning System (GPS), and GSM network are used to track the UAVs; an emergency tracking UAV information database is built in advance by registration, the database at least includes the following information, e.g., the ID of the UAVs, the communication number of the UAVs; when catastrophe happens, the real time location of all UAVs in the database will be gotten using emergency tracking method at first, then the traffic cost time for all UAVs to the disaster region will be calculated based on the UAVs' the real time location and the road network using the nearest services analysis algorithm; the disaster region is subdivided to several emergency surveying regions based on DEM, area, and the population distribution map; the emergency surveying regions are assigned to the appropriated UAV according to shortest cost time rule. The UAVs tracking and scheduling prototype is implemented using SQLServer2008, ArcEnginge 10.1 SDK, Visual Studio 2010 C#, Android, SMS Modem, and Google Maps API.

  19. Intelligent Control Approaches for UAVs

    NASA Technical Reports Server (NTRS)

    KrisnaKumar, Kalmanje

    2003-01-01

    This talk will present overviews of various intelligent control technologies currently being developed and studied at the NASA Ames Research Center as applicable to Unmanned Aerial Vehicles (UAVs), Mars flyers, and to the next generation of flight controllers for manned aircraft. The approaches being examined include: (a) direct adaptive dynamic inverse controller, (b) adaptive critic-based optimal trajectory generator; (c) optimal allocation technique based on linear programming; (4) immunized maneuvering using autopilot building blocks. These approaches can utilize, but do not require, fault detection and isolation information. Piloted and unmanned simulation studies are performed to examine if the intelligent flight control techniques adequately: 1) match flying qualities of modem fly-by-wire flight controllers under nominal conditions; 2) improve performance under failure conditions when sufficient control authority is available; and 3) achieve intelligent maneuvering capabilities for unmanned vehicles. Results obtained so far will be presented and discussed.

  20. Demonstration of UAV deployment and control of mobile wireless sensing networks for modal analysis of structures

    NASA Astrophysics Data System (ADS)

    Zhou, Hao; Hirose, Mitsuhito; Greenwood, William; Xiao, Yong; Lynch, Jerome; Zekkos, Dimitrios; Kamat, Vineet

    2016-04-01

    Unmanned aerial vehicles (UAVs) can serve as a powerful mobile sensing platform for assessing the health of civil infrastructure systems. To date, the majority of their uses have been dedicated to vision and laser-based spatial imaging using on-board cameras and LiDAR units, respectively. Comparatively less work has focused on integration of other sensing modalities relevant to structural monitoring applications. The overarching goal of this study is to explore the ability for UAVs to deploy a network of wireless sensors on structures for controlled vibration testing. The study develops a UAV platform with an integrated robotic gripper that can be used to install wireless sensors in structures, drop a heavy weight for the introduction of impact loads, and to uninstall wireless sensors for reinstallation elsewhere. A pose estimation algorithm is embedded in the UAV to estimate the location of the UAV during sensor placement and impact load introduction. The Martlet wireless sensor network architecture is integrated with the UAV to provide the UAV a mobile sensing capability. The UAV is programmed to command field deployed Martlets, aggregate and temporarily store data from the wireless sensor network, and to communicate data to a fixed base station on site. This study demonstrates the integrated UAV system using a simply supported beam in the lab with Martlet wireless sensors placed by the UAV and impact load testing performed. The study verifies the feasibility of the integrated UAV-wireless monitoring system architecture with accurate modal characteristics of the beam estimated by modal analysis.

  1. Tracking the Creation of Tropical Forest Canopy Gaps with UAV Computer Vision Remote Sensing

    NASA Astrophysics Data System (ADS)

    Dandois, J. P.

    2015-12-01

    The formation of canopy gaps is fundamental for shaping forest structure and is an important component of ecosystem function. Recent time-series of airborne LIDAR have shown great promise for improving understanding of the spatial distribution and size of forest gaps. However, such work typically looks at gap formation across multiple years and important intra-annual variation in gap dynamics remains unknown. Here we present findings on the intra-annual dynamics of canopy gap formation within the 50 ha forest dynamics plot of Barro Colorado Island (BCI), Panama based on unmanned aerial vehicle (UAV) remote sensing. High-resolution imagery (7 cm GSD) over the 50 ha plot was obtained regularly (≈ every 10 days) beginning October 2014 using a UAV equipped with a point and shoot camera. Imagery was processed into three-dimensional (3D) digital surface models (DSMs) using automated computer vision structure from motion / photogrammetric methods. New gaps that formed between each UAV flight were identified by subtracting DSMs between each interval and identifying areas of large deviation. A total of 48 new gaps were detected from 2014-10-02 to 2015-07-23, with sizes ranging from less than 20 m2 to greater than 350 m2. The creation of new gaps was also evaluated across wet and dry seasons with 4.5 new gaps detected per month in the dry season (Jan. - May) and 5.2 per month outside the dry season (Oct. - Jan. & May - July). The incidence of gap formation was positively correlated with ground-surveyed liana stem density (R2 = 0.77, p < 0.001) at the 1 hectare scale. Further research will consider the role of climate in predicting gap formation frequency as well as site history and other edaphic factors. Future satellite missions capable of observing vegetation structure at greater extents and frequencies than airborne observations will be greatly enhanced by the high spatial and temporal resolution bridging scale made possible by UAV remote sensing.

  2. Without gaps - 3D photo-reconstruction of gully headcuts by combined utilisation of UAV and close-range photogrammetry

    NASA Astrophysics Data System (ADS)

    Stöcker, Claudia; Karrasch, Pierre; Eltner, Anette

    2015-04-01

    Gully erosion is a worldwide phenomenon causing permanent degradation of fertile land. Especially in the Mediterranean, gullies contribute to high soil loss rates which necessitate multi-temporal and high resolution monitoring. Gullies naturally exhibit complex surface morphologies and hence are difficult to measure. Images acquired airborne or terrestrial are possible data sources for digital gully modelling due to availing of photogrammetric methods to achieve 3D models. In this regard unmanned airborne vehicles (UAVs) allow for low cost, flexible and frequent areal gully monitoring, but exhibit limitations as a result of the birds-eye view - i.e. at steep sidewalls and overhanging areas. Terrestrial images offer advantages at local assessments and can be obtained spontaneously as needed. However, images acquired from ground are not able to ensure areal coverage. To integrate the advantages of both data sources and to overcome the above mentioned limitations, this study introduces a methodological approach of combined utilisation of nadir UAV data and oblique terrestrial images for 3D photo reconstruction. Two gully headcuts in Andalusia (Spain) are analysed to confirm the suitability of the synergetic data usage. The results show that the UAV model of the gully, generated from images from flying heights of 15 m, implies inconsistency of data at slope gradients of 50 to 60 °. To eliminate these gaps additional terrestrial images can be integrated, which are geo-referenced solely using information of the already calculated 3D model and orthophoto from the UAV images. Referencing errors of the terrestrial point clouds are fixed by applying fine registration. The final merged digital gully model reveals a resolution of 0.5 cm and an accuracy of 1 cm. Concluding, high density point clouds based on the fusion of UAV and terrestrial image data show a significant improvement of 3D photo-reconstruction of two gully headcuts compared to detached processing of single data

  3. Automatic Single Tree Detection in Plantations using UAV-based Photogrammetric Point clouds

    NASA Astrophysics Data System (ADS)

    Kattenborn, T.; Sperlich, M.; Bataua, K.; Koch, B.

    2014-08-01

    For reasons of documentation, management and certification there is a high interest in efficient inventories of palm plantations on the single plant level. Recent developments in unmanned aerial vehicle (UAV) technology facilitate spatial and temporal flexible acquisition of high resolution 3D data. Common single tree detection approaches are based on Very High Resolution (VHR) satellite or Airborne Laser Scanning (ALS) data. However, VHR data is often limited to clouds and does commonly not allow for height measurements. VHR and in particualar ALS data are characterized by high relatively high acquisition costs. Sperlich et al. (2013) already demonstrated the high potential of UAV-based photogrammetric point clouds for single tree detection using pouring algorithms. This approach was adjusted and improved for an application on palm plantation. The 9.4ha test site on Tarawa, Kiribati, comprised densely scattered growing palms, as well as abundant undergrowth and trees. Using a standard consumer grade camera mounted on an octocopter two flight campaigns at 70m and 100m altitude were performed to evaluate the effect Ground Sampling Distance (GSD) and image overlap. To avoid comission errors and improve the terrain interpolation the point clouds were classified based on the geometric characteristics of the classes, i.e. (1) palm, (2) other vegetation (3) and ground. The mapping accuracy amounts for 86.1 % for the entire study area and 98.2 % for dense growing palm stands. We conclude that this flexible and automatic approach has high capabilities for operational use.

  4. Corn and sorghum phenotyping using a fixed-wing UAV-based remote sensing system

    NASA Astrophysics Data System (ADS)

    Shi, Yeyin; Murray, Seth C.; Rooney, William L.; Valasek, John; Olsenholler, Jeff; Pugh, N. Ace; Henrickson, James; Bowden, Ezekiel; Zhang, Dongyan; Thomasson, J. Alex

    2016-05-01

    Recent development of unmanned aerial systems has created opportunities in automation of field-based high-throughput phenotyping by lowering flight operational cost and complexity and allowing flexible re-visit time and higher image resolution than satellite or manned airborne remote sensing. In this study, flights were conducted over corn and sorghum breeding trials in College Station, Texas, with a fixed-wing unmanned aerial vehicle (UAV) carrying two multispectral cameras and a high-resolution digital camera. The objectives were to establish the workflow and investigate the ability of UAV-based remote sensing for automating data collection of plant traits to develop genetic and physiological models. Most important among these traits were plant height and number of plants which are currently manually collected with high labor costs. Vegetation indices were calculated for each breeding cultivar from mosaicked and radiometrically calibrated multi-band imagery in order to be correlated with ground-measured plant heights, populations and yield across high genetic-diversity breeding cultivars. Growth curves were profiled with the aerial measured time-series height and vegetation index data. The next step of this study will be to investigate the correlations between aerial measurements and ground truth measured manually in field and from lab tests.

  5. Automatic Searching Radioactive Sources by Airborne Radioactive Survey Using Multicopter

    NASA Astrophysics Data System (ADS)

    Rim, H.; Eun, S. B.; Kim, K.; Park, S.; Jung, H. K.

    2015-12-01

    In order to prepare emergency situation lost a dangerous radioelement source in advance and to search a radioactive source automatically, we develop airborne radioelement survey system by multicopter. This multicopter radioelement survey system consists of a small portable customized BGO (Bismuth Germanate Oxide) detector, video recording part, wireless connecting part to ground pilot, GPS, and several equipments for automatic flight. This system is possible to search flight by preprogramed lines. This radioactive detecting system are tested to find intentional hidden source, The performance of detecting a source is well proved with very low flight altitude in spite of depending on the magnitude of radioelement sources. The advantage of multicopter system, one of UAV (Unmanned Aerial Vehicle), is to avoid the potential of close access to a dangerous radioactive source by using fully automatic searching capability. In this paper, we introduce our multicopter system for detecting radioactive source and synthetic case history for demonstrating this system.

  6. Output feedback control of a quadrotor UAV using neural networks.

    PubMed

    Dierks, Travis; Jagannathan, Sarangapani

    2010-01-01

    In this paper, a new nonlinear controller for a quadrotor unmanned aerial vehicle (UAV) is proposed using neural networks (NNs) and output feedback. The assumption on the availability of UAV dynamics is not always practical, especially in an outdoor environment. Therefore, in this work, an NN is introduced to learn the complete dynamics of the UAV online, including uncertain nonlinear terms like aerodynamic friction and blade flapping. Although a quadrotor UAV is underactuated, a novel NN virtual control input scheme is proposed which allows all six degrees of freedom (DOF) of the UAV to be controlled using only four control inputs. Furthermore, an NN observer is introduced to estimate the translational and angular velocities of the UAV, and an output feedback control law is developed in which only the position and the attitude of the UAV are considered measurable. It is shown using Lyapunov theory that the position, orientation, and velocity tracking errors, the virtual control and observer estimation errors, and the NN weight estimation errors for each NN are all semiglobally uniformly ultimately bounded (SGUUB) in the presence of bounded disturbances and NN functional reconstruction errors while simultaneously relaxing the separation principle. The effectiveness of proposed output feedback control scheme is then demonstrated in the presence of unknown nonlinear dynamics and disturbances, and simulation results are included to demonstrate the theoretical conjecture.

  7. Orthorectification, mosaicking, and analysis of sub-decimeter resolution UAV imagery for rangeland monitoring

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAVs) offer an attractive platform for acquiring imagery for rangeland monitoring. UAVs can be deployed quickly and repeatedly, and they can obtain sub-decimeter resolution imagery at lower image acquisition costs than with piloted aircraft. Low flying heights result in ima...

  8. Development of an operational UAV / remote sensing capability for rangeland management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland comprises approximately 70% of the Earth’s land surface area. Much of this vast space is in very remote areas with difficult access. Unmanned Aerial Vehicles (UAVs) have great potential for rangeland management applications. UAVs have several advantages over satellites and piloted aircr...

  9. The development of a UGV-mounted automated refueling system for VTOL UAVs

    NASA Astrophysics Data System (ADS)

    Wills, Mike; Burmeister, Aaron; Nelson, Travis; Denewiler, Thomas; Mullens, Kathy

    2006-05-01

    This paper describes the latest efforts to develop an Automated UAV Mission System (AUMS) for small vertical takeoff and landing (VTOL) unmanned air vehicles (UAVs). In certain applications such as force protection, perimeter security, and urban surveillance a VTOL UAV can provide far greater utility than fixed-wing UAVs or ground-based sensors. The VTOL UAV can operate much closer to an object of interest and can provide a hover-and-stare capability to keep its sensors trained on an object, while the fixed wing UAV would be forced into a higher altitude loitering pattern where its sensors would be subject to intermittent blockage by obstacles and terrain. The most significant disadvantage of a VTOL UAV when compared to a fixed-wing UAV is its reduced flight endurance. AUMS addresses this disadvantage by providing forward staging, refueling, and recovery capabilities for the VTOL UAV through a host unmanned ground vehicle (UGV), which serves as a launch/recovery platform and service station. The UGV has sufficient payload capacity to carry UAV fuel for multiple launch, recovery, and refuel iterations. The UGV also provides a highly mobile means of forward deploying a small UAV into hazardous areas unsafe for personnel, such as chemically or biologically contaminated areas. Teaming small UAVs with large UGVs can decrease risk to personnel and expand mission capabilities and effectiveness. There are numerous technical challenges being addressed by these development efforts. Among the challenges is the development and integration of a precision landing system compact and light enough to allow it to be mounted on a small VTOL UAV while providing repeatable landing accuracy to safely land on the AUMS. Another challenge is the design of a UGV-transportable, expandable, self-centering landing pad that contains hardware and safety devices for automatically refueling the UAV. A third challenge is making the design flexible enough to accommodate different types of VTOL UAVs

  10. Performance Evaluation of 3d Modeling Software for Uav Photogrammetry

    NASA Astrophysics Data System (ADS)

    Yanagi, H.; Chikatsu, H.

    2016-06-01

    UAV (Unmanned Aerial Vehicle) photogrammetry, which combines UAV and freely available internet-based 3D modeling software, is widely used as a low-cost and user-friendly photogrammetry technique in the fields such as remote sensing and geosciences. In UAV photogrammetry, only the platform used in conventional aerial photogrammetry is changed. Consequently, 3D modeling software contributes significantly to its expansion. However, the algorithms of the 3D modelling software are black box algorithms. As a result, only a few studies have been able to evaluate their accuracy using 3D coordinate check points. With this motive, Smart3DCapture and Pix4Dmapper were downloaded from the Internet and commercial software PhotoScan was also employed; investigations were performed in this paper using check points and images obtained from UAV.

  11. Ground-based visual guidance in autonomous UAV landing

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Shen, Lincheng; Cong, Yirui; Zhou, Dianle; Zhang, Daibing

    2013-12-01

    Visual guidance has attracted more and more attention in the navigation field thanks to its accuracy and robustness. This paper presents a ground-based visual guidance system for the autonomous Unmanned Aerial Vehicles (UAV) landing. The system consists of two cameras and pan-tilt units (PTU) that mounted on both sides of the runway. In this system, computer vision is adopted for UAV detection and tracking. To be more specific, triangulation, a geometric method in binocular vision, is employed to calculate the 3D coordinates of the UAV in order to provide landing guidance parameters and finally achieve autonomous UAV landing. The 3D positioning principles adopted in ground-based measurement are simulated and verified. The results show that the accuracy can be achieved and relevant requirements are satisfied by ground-based visual guidance.

  12. Critical infrastructure monitoring using UAV imagery

    NASA Astrophysics Data System (ADS)

    Maltezos, Evangelos; Skitsas, Michael; Charalambous, Elisavet; Koutras, Nikolaos; Bliziotis, Dimitris; Themistocleous, Kyriacos

    2016-08-01

    The constant technological evolution in Computer Vision enabled the development of new techniques which in conjunction with the use of Unmanned Aerial Vehicles (UAVs) may extract high quality photogrammetric products for several applications. Dense Image Matching (DIM) is a Computer Vision technique that can generate a dense 3D point cloud of an area or object. The use of UAV systems and DIM techniques is not only a flexible and attractive solution to produce accurate and high qualitative photogrammetric results but also is a major contribution to cost effectiveness. In this context, this study aims to highlight the benefits of the use of the UAVs in critical infrastructure monitoring applying DIM. A Multi-View Stereo (MVS) approach using multiple images (RGB digital aerial and oblique images), to fully cover the area of interest, is implemented. The application area is an Olympic venue in Attica, Greece, at an area of 400 acres. The results of our study indicate that the UAV+DIM approach respond very well to the increasingly greater demands for accurate and cost effective applications when provided with, a 3D point cloud and orthomosaic.

  13. UAV for landslide mapping and deformation analysis

    NASA Astrophysics Data System (ADS)

    Shi, Beiqi; Liu, Chun

    2015-12-01

    Unmanned aerial vehicle (UAV) can be a flexible, cost-effective, and accurate method to monitor landslides with high resolution aerial images. Images acquired on 05 May 2013 and 13 December 2014 of the Xishan landslide, China, have been used to produce a high-resolution ortho-mosaic of the entire landslide and digital elevation model (DEM). The UAV capability for imaging detection and displacements on the landslide surface has been evaluated, and the subsequent image processing approaches for suitably georectifying the data have been assessed. Objects derived from the segmentation of a multispectral image were used as classifying units for landslide object-oriented analysis. Spectral information together with various morphometric characteristics was applied for recognizing landslides from false positives. Digital image correlation technique was evaluated to quantify and map terrain displacements. The magnitude and direction of the displacement vectors derived from correlating two temporal UAV images corresponded to a visual interpretation of landslide change. Therefore, the UAV can demonstrate its capability for producing valuable landslide mapping data and deformation information.

  14. Optimal Path Planning and Control of Quadrotor Unmanned Aerial Vehicle for Area Coverage

    NASA Astrophysics Data System (ADS)

    Fan, Jiankun

    An Unmanned Aerial Vehicle (UAV) is an aircraft without a human pilot on board. Its flight is controlled either autonomously by computers onboard the vehicle, or remotely by a pilot on the ground, or by another vehicle. In recent years, UAVs have been used more commonly than prior years. The example includes areo-camera where a high speed camera was attached to a UAV which can be used as an airborne camera to obtain aerial video. It also could be used for detecting events on ground for tasks such as surveillance and monitoring which is a common task during wars. Similarly UAVs can be used for relaying communication signal during scenarios when regular communication infrastructure is destroyed. The objective of this thesis is motivated from such civilian operations such as search and rescue or wildfire detection and monitoring. One scenario is that of search and rescue where UAV's objective is to geo-locate a person in a given area. The task is carried out with the help of a camera whose live feed is provided to search and rescue personnel. For this objective, the UAV needs to carry out scanning of the entire area in the shortest time. The aim of this thesis to develop algorithms to enable a UAV to scan an area in optimal time, a problem referred to as "Coverage Control" in literature. The thesis focuses on a special kind of UAVs called "quadrotor" that is propelled with the help of four rotors. The overall objective of this thesis is achieved via solving two problems. The first problem is to develop a dynamic control model of quadrtor. In this thesis, a proportional-integral-derivative controller (PID) based feedback control system is developed and implemented on MATLAB's Simulink. The PID controller helps track any given trajectory. The second problem is to design a trajectory that will fulfill the mission. The planed trajectory should make sure the quadrotor will scan the whole area without missing any part to make sure that the quadrotor will find the lost

  15. Experiences of Uav Surveys Applied to Environmental Risk Management

    NASA Astrophysics Data System (ADS)

    Caprioli, M.; Trizzino, R.; Mazzone, F.; Scarano, M.

    2016-06-01

    In this paper the results of some surveys carried out in an area of Apulian territory affected by serious environmental hazard are presented. Unmanned Aerial Vehicles (UAV) are emerging as a key engineering tool for future environmental survey tasks. UAVs are increasingly seen as an attractive low-cost alternative or supplement to aerial and terrestrial photogrammetry due to their low cost, flexibility, availability and readiness for duty. In addition, UAVs can be operated in hazardous or temporarily inaccessible locations, that makes them very suitable for the assessment and management of environmental risk conditions. In order to verify the reliability of these technologies an UAV survey and A LIDAR survey have been carried outalong about 1 km of coast in the Salento peninsula, near the towns of San Foca, Torre dellOrso and SantAndrea( Lecce, Southern Italy). This area is affected by serious environmental risks due to the presence of dangerous rocky cliffs named falesie. The UAV platform was equipped with a photogrammetric measurement system that allowed us to obtain a mobile mapping of the fractured fronts of dangerous rocky cliffs. UAV-images data have been processed using dedicated software (AgisoftPhotoscan). The point clouds obtained from both the UAV and LIDAR surveys have been processed using Cloud Compare software, with the aim of testing the UAV results with respect to the LIDAR ones. The total error obtained was of centimeter-order that is a very satisfactory result. The environmental information has been arranged in an ArcGIS platform in order to assess the risk levels. The possibility to repeat the survey at time intervals more or less close together depending on the measured levels of risk and to compare the output allows following the trend of the dangerous phenomena. In conclusion, for inaccessible locations of dangerous rocky bodies the UAV survey coupled with GIS methodology proved to be a key engineering tool for the management of environmental

  16. Illumination-invariant image matching for autonomous UAV localisation based on optical sensing

    NASA Astrophysics Data System (ADS)

    Wan, Xue; Liu, Jianguo; Yan, Hongshi; Morgan, Gareth L. K.

    2016-09-01

    This paper presents an UAV (Unmanned Aerial Vehicle) localisation algorithm for its autonomous navigation based on matching between on-board UAV image sequences to a pre-installed reference satellite image. As the UAV images and the reference image are not necessarily taken under the same illumination condition, illumination-invariant image matching is essential. Based on the investigation of illumination-invariant property of Phase Correlation (PC) via mathematical derivation and experiments, we propose a PC based fast and robust illumination-invariant localisation algorithm for UAV navigation. The algorithm accurately determines the current UAV position as well as the next UAV position even the illumination condition of UAV on-board images is different from the reference satellite image. A Dirac delta function based registration quality assessment together with a risk alarming criterion is introduced to enable the UAV to perform self-correction in case the UAV deviates from the planned route. UAV navigation experiments using simulated terrain shading images and remote sensing images have demonstrated a robust high performance of the proposed PC based localisation algorithm under very different illumination conditions resulted from solar motion. The superiority of the algorithm, in comparison with two other widely used image matching algorithms, MI (Mutual Information) and NCC (Normalised Correlation Coefficient), is significant for its high matching accuracy and fast processing speed.

  17. Stochastic control of light UAV at landing with the aid of bearing-only observations

    NASA Astrophysics Data System (ADS)

    Miller, Alexander; Miller, Boris

    2015-12-01

    This work considers the tracking of the UAV (unmanned aviation vehicle) at landing on unprepared field. Despite the advantages in UAV guidance the autonomous landing remains to be one of most serious problems. The principal difficulties are the absence of the precise UAV position measurements with respect to the landing field and the action of external atmospheric perturbations (turbulence and wind). So the control problem for UAV landing is the nonlinear stochastic one with incomplete information. The aim of the article is the development of stochastic control algorithms based on pseudomeasurement Kalman filter in the problem of the UAV autonomous landing with the aid of ground-based optical/radio radars in the case of strong wind and large initial error of the UAV entrance into the area covered by radars. The novelty of the article is the joint control-observation algorithm based on unbiased pseudomeasurement Kalman filter which provides the quadratic characteristics of the estimation errors. The later property is highly important for the UAV control based on the data fusion from INS (inertial navigation system) and the bearing observations obtained from external terrain based locators. The principal difficulty in the UAV landing control is the absence of the direct control tools at the terrain end, so the possible control can be based on the angular-range data obtained by terrain locators which must be transmitted from terrain location station to the UAV control unit. Thus the stochastic approach looks very effective in this challenging problem of the UAV landing.

  18. Autonomous landing of a helicopter UAV with a ground-based multisensory fusion system

    NASA Astrophysics Data System (ADS)

    Zhou, Dianle; Zhong, Zhiwei; Zhang, Daibing; Shen, Lincheng; Yan, Chengping

    2015-02-01

    In this study, this paper focus on the vision-based autonomous helicopter unmanned aerial vehicle (UAV) landing problems. This paper proposed a multisensory fusion to autonomous landing of an UAV. The systems include an infrared camera, an Ultra-wideband radar that measure distance between UAV and Ground-Based system, an PAN-Tilt Unit (PTU). In order to identify all weather UAV targets, we use infrared cameras. To reduce the complexity of the stereovision or one-cameral calculating the target of three-dimensional coordinates, using the ultra-wideband radar distance module provides visual depth information, real-time Image-PTU tracking UAV and calculate the UAV threedimensional coordinates. Compared to the DGPS, the test results show that the paper is effectiveness and robustness.

  19. Persistent unmanned airborne network support for cooperative sensors

    NASA Astrophysics Data System (ADS)

    Verma, Ajay; Fernandes, Ronald

    2013-05-01

    In future we expect that UAV platoon based military / civilian missions would require persistent airborne network support for command, control and communication needs for the mission. Highly-dynamic mobile-wireless sensor networks operating in a large region present unique challenges in end-to-end communication for sensor data sharing and data fusion, particularly caused by the time varying connectivity of high-velocity nodes combined with the unreliability of the wireless communication channel. To establish an airborne communication network, a UAV must maintain a link(s) with other UAV(s) and/or base stations. A link between two UAVs is deemed to be established when the linked UAVs are in line of sight as well as within the transmission range of each other. Ideally, all the UAVs as well as the ground stations involved in command, control and communication operations must be fully connected. However, the continuous motion of UAVs poses a challenge to ensure full connectivity of the network. In this paper we explore the dynamic topological network configuration control under mission-related constraints in order to maintain connectivity among sensors enabling data sharing.

  20. Energy-Efficient Systems Eliminate Icing Danger for UAVs

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Ames Research Center engineer Leonard Haslim invented an anti-icing t echnology called an electroexpulsive separation system, which uses m echanical force to shatter potentially dangerous ice buildup on an ai rcraft surface. Temecula, California-based Ice Management Systems (no w known as IMS-ESS) licensed the technology from Ames and has discov ered a niche market for the lightweight, energy-efficient technology: unmanned aerial vehicles (UAVs). IMS-ESS systems now prevent damagi ng ice accumulation on military UAVs, allowing the vehicles to carry out crucial missions year round.

  1. NASA Earth Science Research and Applications Using UAVs

    NASA Technical Reports Server (NTRS)

    Guillory, Anthony R.

    2003-01-01

    The NASA Earth Science Enterprise sponsored the UAV Science Demonstration Project, which funded two projects: the Altus Cumulus Electrification Study (ACES) and the UAV Coffee Harvest Optimization experiment. These projects were intended to begin a process of integrating UAVs into the mainstream of NASA s airborne Earth Science Research and Applications programs. The Earth Science Enterprise is moving forward given the positive science results of these demonstration projects to incorporate more platforms with additional scientific utility into the program and to look toward a horizon where the current piloted aircraft may not be able to carry out the science objectives of a mission. Longer duration, extended range, slower aircraft speed, etc. all have scientific advantages in many of the disciplines within Earth Science. The challenge we now face are identifying those capabilities that exist and exploiting them while identifying the gaps. This challenge has two facets: the engineering aspects of redesigning or modifying sensors and a paradigm shift by the scientists.

  2. COCAP - A compact carbon dioxide analyser for airborne platforms

    NASA Astrophysics Data System (ADS)

    Kunz, Martin; Lavrič, Jošt V.; Jeschag, Wieland; Bryzgalov, Maksym; Hök, Bertil; Heimann, Martin

    2014-05-01

    Airborne platforms are a valuable tool for atmospheric trace gas measurements due to their capability of movement in three dimensions, covering spatial scales from metres to thousands of kilometres. Although crewed research aircraft are flexible in payload and range, their use is limited by high initial and operating costs. Small unmanned aerial vehicles (UAV) have the potential for substantial cost reduction, but require lightweight, miniaturized and energy-efficient scientific equipment. We are developing a COmpact Carbon dioxide analyser for Airborne Platforms (COCAP). It contains a non-dispersive infrared CO2sensor with a nominal full scale of 3000 μmol/mol. Sampled air is dried with magnesium perchlorate before it enters the sensor. This enables measurement of the dry air mole fraction of CO2, as recommended by the World Meteorological Organization. During post-processing, the CO2 measurement is corrected for temperature and pressure variations in the gas line. Allan variance analysis shows that we achieve a precision of better than 0.4 μmol/mol for 10 s averaging time. We plan to monitor the analyser's stability during flight by measuring reference air from a miniature gas tank in regular intervals. Besides CO2, COCAP measures relative humidity, temperature and pressure of ambient air. An on-board GPS receiver delivers accurate timestamps and allows georeferencing. Data is both stored on a microSD card and simultaneously transferred over a wireless serial interface to a ground station for real-time review. The target weight for COCAP is less than 1 kg. We deploy COCAP on a commercially available fixed-wing UAV (Bormatec Explorer) with a wingspan of 2.2 metres. The UAV has high payload capacity (2.5 kg) as well as sufficient space in the fuselage (80x80x600 mm3). It is built from a shock-resistant foam material, which allows quick repair of minor damages in the field. In case of severe damage spare parts are readily available. Calculations suggest that the

  3. Thermal Infrared Spectral Imager for Airborne Science Applications

    NASA Technical Reports Server (NTRS)

    Johnson, William R.; Hook, Simon J.; Mouroulis, Pantazis; Wilson, Daniel W.; Gunapala, Sarath D.; Hill, Cory J.; Mumolo, Jason M.; Eng, Bjorn T.

    2009-01-01

    An airborne thermal hyperspectral imager is under development which utilizes the compact Dyson optical configuration and quantum well infrared photo detector (QWIP) focal plane array. The Dyson configuration uses a single monolithic prism-like grating design which allows for a high throughput instrument (F/1.6) with minimal ghosting, stray-light and large swath width. The configuration has the potential to be the optimal imaging spectroscopy solution for lighter-than-air (LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The planned instrument specifications are discussed as well as design trade-offs. Calibration testing results (noise equivalent temperature difference, spectral linearity and spectral bandwidth) and laboratory emissivity plots from samples are shown using an operational testbed unit which has similar specifications as the final airborne system. Field testing of the testbed unit was performed to acquire plots of apparent emissivity for various known standard minerals (such as quartz). A comparison is made using data from the ASTER spectral library.

  4. Geometric and Reflectance Signature Characterization of Complex Canopies Using Hyperspectral Stereoscopic Images from Uav and Terrestrial Platforms

    NASA Astrophysics Data System (ADS)

    Honkavaara, E.; Hakala, T.; Nevalainen, O.; Viljanen, N.; Rosnell, T.; Khoramshahi, E.; Näsi, R.; Oliveira, R.; Tommaselli, A.

    2016-06-01

    Light-weight hyperspectral frame cameras represent novel developments in remote sensing technology. With frame camera technology, when capturing images with stereoscopic overlaps, it is possible to derive 3D hyperspectral reflectance information and 3D geometric data of targets of interest, which enables detailed geometric and radiometric characterization of the object. These technologies are expected to provide efficient tools in various environmental remote sensing applications, such as canopy classification, canopy stress analysis, precision agriculture, and urban material classification. Furthermore, these data sets enable advanced quantitative, physical based retrieval of biophysical and biochemical parameters by model inversion technologies. Objective of this investigation was to study the aspects of capturing hyperspectral reflectance data from unmanned airborne vehicle (UAV) and terrestrial platform with novel hyperspectral frame cameras in complex, forested environment.

  5. Multi-UAV Routing for Area Coverage and Remote Sensing with Minimum Time.

    PubMed

    Avellar, Gustavo S C; Pereira, Guilherme A S; Pimenta, Luciano C A; Iscold, Paulo

    2015-11-02

    This paper presents a solution for the problem of minimum time coverage of ground areas using a group of unmanned air vehicles (UAVs) equipped with image sensors. The solution is divided into two parts: (i) the task modeling as a graph whose vertices are geographic coordinates determined in such a way that a single UAV would cover the area in minimum time; and (ii) the solution of a mixed integer linear programming problem, formulated according to the graph variables defined in the first part, to route the team of UAVs over the area. The main contribution of the proposed methodology, when compared with the traditional vehicle routing problem's (VRP) solutions, is the fact that our method solves some practical problems only encountered during the execution of the task with actual UAVs. In this line, one of the main contributions of the paper is that the number of UAVs used to cover the area is automatically selected by solving the optimization problem. The number of UAVs is influenced by the vehicles' maximum flight time and by the setup time, which is the time needed to prepare and launch a UAV. To illustrate the methodology, the paper presents experimental results obtained with two hand-launched, fixed-wing UAVs.

  6. Multi-UAV Routing for Area Coverage and Remote Sensing with Minimum Time.

    PubMed

    Avellar, Gustavo S C; Pereira, Guilherme A S; Pimenta, Luciano C A; Iscold, Paulo

    2015-01-01

    This paper presents a solution for the problem of minimum time coverage of ground areas using a group of unmanned air vehicles (UAVs) equipped with image sensors. The solution is divided into two parts: (i) the task modeling as a graph whose vertices are geographic coordinates determined in such a way that a single UAV would cover the area in minimum time; and (ii) the solution of a mixed integer linear programming problem, formulated according to the graph variables defined in the first part, to route the team of UAVs over the area. The main contribution of the proposed methodology, when compared with the traditional vehicle routing problem's (VRP) solutions, is the fact that our method solves some practical problems only encountered during the execution of the task with actual UAVs. In this line, one of the main contributions of the paper is that the number of UAVs used to cover the area is automatically selected by solving the optimization problem. The number of UAVs is influenced by the vehicles' maximum flight time and by the setup time, which is the time needed to prepare and launch a UAV. To illustrate the methodology, the paper presents experimental results obtained with two hand-launched, fixed-wing UAVs. PMID:26540055

  7. Uav Borne Low Altitude Photogrammetry System

    NASA Astrophysics Data System (ADS)

    Lin, Z.; Su, G.; Xie, F.

    2012-07-01

    In this paper,the aforementioned three major aspects related to the Unmanned Aerial Vehicles (UAV) system for low altitude aerial photogrammetry, i.e., flying platform, imaging sensor system and data processing software, are discussed. First of all, according to the technical requirements about the least cruising speed, the shortest taxiing distance, the level of the flight control and the performance of turbulence flying, the performance and suitability of the available UAV platforms (e.g., fixed wing UAVs, the unmanned helicopters and the unmanned airships) are compared and analyzed. Secondly, considering the restrictions on the load weight of a platform and the resolution pertaining to a sensor, together with the exposure equation and the theory of optical information, the principles of designing self-calibration and self-stabilizing combined wide-angle digital cameras (e.g., double-combined camera and four-combined camera) are placed more emphasis on. Finally, a software named MAP-AT, considering the specialty of UAV platforms and sensors, is developed and introduced. Apart from the common functions of aerial image processing, MAP-AT puts more effort on automatic extraction, automatic checking and artificial aided adding of the tie points for images with big tilt angles. Based on the recommended process for low altitude photogrammetry with UAVs in this paper, more than ten aerial photogrammetry missions have been accomplished, the accuracies of Aerial Triangulation, Digital orthophotos(DOM)and Digital Line Graphs(DLG) of which meet the standard requirement of 1:2000, 1:1000 and 1:500 mapping.

  8. Technologies Advance UAVs for Science, Military

    NASA Technical Reports Server (NTRS)

    2010-01-01

    A Space Act Agreement with Goddard Space Flight Center and West Virginia University enabled Aurora Flight Sciences Corporation, of Manassas, Virginia, to develop cost-effective composite manufacturing capabilities and open a facility in West Virginia. The company now employs 160 workers at the plant, tasked with crafting airframe components for the Global Hawk unmanned aerial vehicle (UAV) program. While one third of the company's workforce focuses on Global Hawk production, the rest of the company develops advanced UAV technologies that are redefining traditional approaches to unmanned aviation. Since the company's founding, Aurora s cutting-edge work has been supported with funding from NASA's Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs.

  9. Two-Step Camera Calibration Method Developed for Micro UAV'S

    NASA Astrophysics Data System (ADS)

    Gašparović, M.; Gajski, D.

    2016-06-01

    The development of unmanned aerial vehicles (UAVs) and continuous price reduction of unmanned systems attracted us to this research. Professional measuring systems are dozens of times more expensive and often heavier than "amateur", non-metric UAVs. For this reason, we tested the DJI Phantom 2 Vision Plus UAV. Phantom's smaller mass and velocity can develop less kinetic energy in relation to the professional measurement platforms, which makes it potentially less dangerous for use in populated areas. In this research, we wanted to investigate the ability of such non-metric UAV and find the procedures under which this kind of UAV may be used for the photogrammetric survey. It is important to emphasize that UAV is equipped with an ultra wide-angle camera with 14MP sensor. Calibration of such cameras is a complex process. In the research, a new two-step process is presented and developed, and the results are compared with standard one-step camera calibration procedure. Two-step process involves initially removed distortion on all images, and then uses these images in the phototriangulation with self-calibration. The paper presents statistical indicators which proved that the proposed two-step process is better and more accurate procedure for calibrating those types of cameras than standard one-step calibration. Also, we suggest two-step calibration process as the standard for ultra-wideangle cameras for unmanned aircraft.

  10. A Natural Interaction Interface for UAVs Using Intuitive Gesture Recognition

    NASA Technical Reports Server (NTRS)

    Chandarana, Meghan; Trujillo, Anna; Shimada, Kenji; Allen, Danette

    2016-01-01

    The popularity of unmanned aerial vehicles (UAVs) is increasing as technological advancements boost their favorability for a broad range of applications. One application is science data collection. In fields like Earth and atmospheric science, researchers are seeking to use UAVs to augment their current portfolio of platforms and increase their accessibility to geographic areas of interest. By increasing the number of data collection platforms UAVs will significantly improve system robustness and allow for more sophisticated studies. Scientists would like be able to deploy an available fleet of UAVs to fly a desired flight path and collect sensor data without needing to understand the complex low-level controls required to describe and coordinate such a mission. A natural interaction interface for a Ground Control System (GCS) using gesture recognition is developed to allow non-expert users (e.g., scientists) to define a complex flight path for a UAV using intuitive hand gesture inputs from the constructed gesture library. The GCS calculates the combined trajectory on-line, verifies the trajectory with the user, and sends it to the UAV controller to be flown.

  11. Videometric terminal guidance method and system for UAV accurate landing

    NASA Astrophysics Data System (ADS)

    Zhou, Xiang; Lei, Zhihui; Yu, Qifeng; Zhang, Hongliang; Shang, Yang; Du, Jing; Gui, Yang; Guo, Pengyu

    2012-06-01

    We present a videometric method and system to implement terminal guidance for Unmanned Aerial Vehicle(UAV) accurate landing. In the videometric system, two calibrated cameras attached to the ground are used, and a calibration method in which at least 5 control points are applied is developed to calibrate the inner and exterior parameters of the cameras. Cameras with 850nm spectral filter are used to recognize a 850nm LED target fixed on the UAV which can highlight itself in images with complicated background. NNLOG (normalized negative laplacian of gaussian) operator is developed for automatic target detection and tracking. Finally, 3-D position of the UAV with high accuracy can be calculated and transfered to control system to direct UAV accurate landing. The videometric system can work in the rate of 50Hz. Many real flight and static accuracy experiments demonstrate the correctness and veracity of the method proposed in this paper, and they also indicate the reliability and robustness of the system proposed in this paper. The static accuracy experiment results show that the deviation is less-than 10cm when target is far from the cameras and lessthan 2cm in 100m region. The real flight experiment results show that the deviation from DGPS is less-than 20cm. The system implement in this paper won the first prize in the AVIC Cup-International UAV Innovation Grand Prix, and it is the only one that achieved UAV accurate landing without GPS or DGPS.

  12. Airborne polybrominated diphenyl ethers (PBDEs), polybrominated dibenzo-p-dioxins/furans (PBDD/Fs), and dechlorane plus (DP) in concentrated vehicle parking areas.

    PubMed

    Li, Huiru; Liu, Hehuan; Mo, Ligui; Sheng, Guoying; Fu, Jiamo; Peng, Ping'an

    2016-06-01

    This study investigated polybrominated diphenyl ethers (PBDEs), polybrominated dibenzo-p-dioxins/furans (PBDD/Fs), and dechlorane plus (DP) in air around three concentrated vehicle parking areas (underground, indoor, and outdoor) in a metropolitan of South China. The parking areas showed higher concentrations of PBDEs, PBDD/Fs, and DP than their adjacent urban area or distinct congener/isomer profiles, which indicate their local emission sources. The highest PBDE and DP concentrations were found in the outdoor parking lot, which might be related to the heating effect of direct sunlight exposure. Multi-linear regression analysis results suggest that deca-BDEs without noticeable transformation contributed most to airborne PBDEs in all studied areas, followed by penta-BDEs. The statistically lower anti-DP fractions in the urban area than that of commercial product signified its degradation/transformation during transportation. Neither PBDEs nor vehicle exhaust contributed much to airborne PBDD/Fs in the parking areas. There were 68.1-100 % of PBDEs, PBDD/Fs, and DP associated with particles. Logarithms of gas-particle distribution coefficients (K ps) of PBDEs were significantly linear-correlated with those of their sub-cooled vapor pressures (p Ls) and octanol-air partition coefficients (K OAs) in all studied areas. The daily inhalation doses of PBDEs, DP, and PBDD/Fs were individually estimated as 89.7-10,741, 2.05-39.4, and 0.12-4.17 pg kg(-1) day(-1) for employees in the parking areas via Monte Carlo simulation.

  13. Path planning and Ground Control Station simulator for UAV

    NASA Astrophysics Data System (ADS)

    Ajami, A.; Balmat, J.; Gauthier, J.-P.; Maillot, T.

    In this paper we present a Universal and Interoperable Ground Control Station (UIGCS) simulator for fixed and rotary wing Unmanned Aerial Vehicles (UAVs), and all types of payloads. One of the major constraints is to operate and manage multiple legacy and future UAVs, taking into account the compliance with NATO Combined/Joint Services Operational Environment (STANAG 4586). Another purpose of the station is to assign the UAV a certain degree of autonomy, via autonomous planification/replanification strategies. The paper is organized as follows. In Section 2, we describe the non-linear models of the fixed and rotary wing UAVs that we use in the simulator. In Section 3, we describe the simulator architecture, which is based upon interacting modules programmed independently. This simulator is linked with an open source flight simulator, to simulate the video flow and the moving target in 3D. To conclude this part, we tackle briefly the problem of the Matlab/Simulink software connection (used to model the UAV's dynamic) with the simulation of the virtual environment. Section 5 deals with the control module of a flight path of the UAV. The control system is divided into four distinct hierarchical layers: flight path, navigation controller, autopilot and flight control surfaces controller. In the Section 6, we focus on the trajectory planification/replanification question for fixed wing UAV. Indeed, one of the goals of this work is to increase the autonomy of the UAV. We propose two types of algorithms, based upon 1) the methods of the tangent and 2) an original Lyapunov-type method. These algorithms allow either to join a fixed pattern or to track a moving target. Finally, Section 7 presents simulation results obtained on our simulator, concerning a rather complicated scenario of mission.

  14. 3D Modelling of Inaccessible Areas using UAV-based Aerial Photography and Structure from Motion

    NASA Astrophysics Data System (ADS)

    Obanawa, Hiroyuki; Hayakawa, Yuichi; Gomez, Christopher

    2014-05-01

    In hardly accessible areas, the collection of 3D point-clouds using TLS (Terrestrial Laser Scanner) can be very challenging, while airborne equivalent would not give a correct account of subvertical features and concave geometries like caves. To solve such problem, the authors have experimented an aerial photography based SfM (Structure from Motion) technique on a 'peninsular-rock' surrounded on three sides by the sea at a Pacific coast in eastern Japan. The research was carried out using UAS (Unmanned Aerial System) combined with a commercial small UAV (Unmanned Aerial Vehicle) carrying a compact camera. The UAV is a DJI PHANTOM: the UAV has four rotors (quadcopter), it has a weight of 1000 g, a payload of 400 g and a maximum flight time of 15 minutes. The camera is a GoPro 'HERO3 Black Edition': resolution 12 million pixels; weight 74 g; and 0.5 sec. interval-shot. The 3D model has been constructed by digital photogrammetry using a commercial SfM software, Agisoft PhotoScan Professional®, which can generate sparse and dense point-clouds, from which polygonal models and orthophotographs can be calculated. Using the 'flight-log' and/or GCPs (Ground Control Points), the software can generate digital surface model. As a result, high-resolution aerial orthophotographs and a 3D model were obtained. The results have shown that it was possible to survey the sea cliff and the wave cut-bench, which are unobservable from land side. In details, we could observe the complexity of the sea cliff that is nearly vertical as a whole while slightly overhanging over the thinner base. The wave cut bench is nearly flat and develops extensively at the base of the cliff. Although there are some evidences of small rockfalls at the upper part of the cliff, there is no evidence of very recent activity, because no fallen rock exists on the wave cut bench. This system has several merits: firstly lower cost than the existing measuring methods such as manned-flight survey and aerial laser

  15. Development of Open source-based automatic shooting and processing UAV imagery for Orthoimage Using Smart Camera UAV

    NASA Astrophysics Data System (ADS)

    Park, J. W.; Jeong, H. H.; Kim, J. S.; Choi, C. U.

    2016-06-01

    Recently, aerial photography with unmanned aerial vehicle (UAV) system uses UAV and remote controls through connections of ground control system using bandwidth of about 430 MHz radio Frequency (RF) modem. However, as mentioned earlier, existing method of using RF modem has limitations in long distance communication. The Smart Camera equipments's LTE (long-term evolution), Bluetooth, and Wi-Fi to implement UAV that uses developed UAV communication module system carried out the close aerial photogrammetry with the automatic shooting. Automatic shooting system is an image capturing device for the drones in the area's that needs image capturing and software for loading a smart camera and managing it. This system is composed of automatic shooting using the sensor of smart camera and shooting catalog management which manages filmed images and information. Processing UAV imagery module used Open Drone Map. This study examined the feasibility of using the Smart Camera as the payload for a photogrammetric UAV system. The open soure tools used for generating Android, OpenCV (Open Computer Vision), RTKLIB, Open Drone Map.

  16. Fuzzy decision trees for planning and autonomous control of a coordinated team of UAVs

    NASA Astrophysics Data System (ADS)

    Smith, James F., III; Nguyen, ThanhVu H.

    2007-04-01

    A fuzzy logic resource manager that enables a collection of unmanned aerial vehicles (UAVs) to automatically cooperate to make meteorological measurements will be discussed. Once in flight no human intervention is required. Planning and real-time control algorithms determine the optimal trajectory and points each UAV will sample, while taking into account the UAVs' risk, risk tolerance, reliability, mission priority, fuel limitations, mission cost, and related uncertainties. The control algorithm permits newly obtained information about weather and other events to be introduced to allow the UAVs to be more effective. The approach is illustrated by a discussion of the fuzzy decision tree for UAV path assignment and related simulation. The different fuzzy membership functions on the tree are described in mathematical detail. The different methods by which this tree is obtained are summarized including a method based on using a genetic program as a data mining function. A second fuzzy decision tree that allows the UAVs to automatically collaborate without human intervention is discussed. This tree permits three different types of collaborative behavior between the UAVs. Simulations illustrating how the tree allows the different types of collaboration to be automated are provided. Simulations also show the ability of the control algorithm to allow UAVs to effectively cooperate to increase the UAV team's likelihood of success.

  17. Multi-UAV Routing for Area Coverage and Remote Sensing with Minimum Time

    PubMed Central

    Avellar, Gustavo S. C.; Pereira, Guilherme A. S.; Pimenta, Luciano C. A.; Iscold, Paulo

    2015-01-01

    This paper presents a solution for the problem of minimum time coverage of ground areas using a group of unmanned air vehicles (UAVs) equipped with image sensors. The solution is divided into two parts: (i) the task modeling as a graph whose vertices are geographic coordinates determined in such a way that a single UAV would cover the area in minimum time; and (ii) the solution of a mixed integer linear programming problem, formulated according to the graph variables defined in the first part, to route the team of UAVs over the area. The main contribution of the proposed methodology, when compared with the traditional vehicle routing problem’s (VRP) solutions, is the fact that our method solves some practical problems only encountered during the execution of the task with actual UAVs. In this line, one of the main contributions of the paper is that the number of UAVs used to cover the area is automatically selected by solving the optimization problem. The number of UAVs is influenced by the vehicles’ maximum flight time and by the setup time, which is the time needed to prepare and launch a UAV. To illustrate the methodology, the paper presents experimental results obtained with two hand-launched, fixed-wing UAVs. PMID:26540055

  18. Project Stork UAV/UGV collaborative initiative

    NASA Astrophysics Data System (ADS)

    Schulteis, Timothy M.; Price, John G.

    2004-09-01

    One of the key issues in military urban operations is the ability to obtain timely situational awareness of the target area. One solution utilizes Unmanned Ground Vehicles (UGVs) to provide this information but challenges remain as to how to accurately emplace and control these vehicles from extended ranges. This research and development project, Stork, demonstrated the capability to aerially insert a UGV from a UAV into an area of operations and then use a communications relay pod on the UAV to extend the range of control of UGVs. The UGV insertion was done using a parachute delivery system from after an altitude of 400 feet. The communications relay pod effectively increased the tele-operated control range of the UGV from typical 1-2 km line-of-sight limitation. Tele-operated control was demonstrated out to a distance of 26 km. Transparent to the physical elements of the demonstration was the integration of the Joint Architecture for Unmanned Systems (JAUS) on the UGVs which allows a single operator control unit (OCU) to control multiple disparate UGVs simply by selecting a particular UGV from a drop-down menu. The ability to control multiple vehicles on the ground at the extended range and switch control from one vehicle to the next and back was also successfully demonstrated.

  19. Mapping Glacier Dynamics and Proglacial Wetlands with a Multispectral UAV at 5000m in the Cordillera Blanca, Peru

    NASA Astrophysics Data System (ADS)

    Wigmore, O.; Mark, B. G.

    2015-12-01

    The glaciers of the Cordillera Blanca, Peru are rapidly retreating as a result of rising temperatures, transforming the hydrology and impacting the socio-economic and environmental systems of the Rio Santa basin. Documenting the heterogeneous spatial patterns of these changes to understand processes of water storage and flow is hindered by technologic and logistic challenges. Highly complex topography, cloud cover and coarse spatial resolution limit the application of satellite data while airborne data collection remains costly and potentially dangerous. However, recent developments have made Unmanned Aerial Vehicle (UAV) technology a viable and potentially transformative method for studying glacier dynamics and proglacial hydrology. The extreme altitudes (4000-6700m) of the Cordillera Blanca limit the use of 'off the shelf' UAVs. Therefore we developed a low cost multispectral (visible, near-infrared and thermal infrared) multirotor UAV capable of conducting fully autonomous aerial surveys at elevations over 5000m within the glacial valleys of the Cordillera Blanca. Using this platform we have completed repeat aerial surveys (in 2014 and 2015) of the debris covered Llaca Glacier, generating highly accurate 10-20cm DEM's and 5cm orthomosaics using a structure from motion workflow. Analysis of these data reveals a highly dynamic system with some areas of the glacier losing as much as 16m of vertical elevation, while other areas have gained up to 5m of elevation over one year. The magnitude and direction of these changes appears to be associated with the presence of debris free ice faces and meltwater ponds. Additionally, we have mapped proglacial meadow and wetland systems. Thermal mosaics at 10-20cm resolution are providing novel insights into the hydrologic pathways of glacier meltwater including mapping the distribution of artesian springs that feed these wetland systems. The high spatial resolution of these UAV datasets facilitates a better understanding of the

  20. Synthesis and validation of flight control for UAV

    NASA Astrophysics Data System (ADS)

    Paw, Yew Chai

    Unmanned Aerial Vehicles (UAVs) are widely used worldwide for a board range of civil and military applications. There continues to be a growing demand for reliable and low cost UAV systems. This is especially true for small-size mini UAV systems where majority of systems are still deployed as prototypes due to their lack of reliability. Improvement in the modeling, testing and flight control for the small UAVs would increase their reliability during autonomous flight. The traditional approach used in manned aircraft and large UAV system synthesizing, implementing and validating the flight control system to achieve desired objectives is time consuming and resource intensive. This thesis aims to provide an integrated framework with systematic procedures to synthesize and validate flight controllers. This will help in the certification of UAV system and provide rapid development cycle from simulation to real system flight testing. The effectiveness of the approach is demonstrated by applying the developed framework on a small UAV system that was developed at the University of Minnesota. The thesis is divided into four main parts. The first part is mathematical modeling of the UAV nonlinear simulation model using first principle theory. Flight test system identification technique is used to extract model and model uncertainty parameters to update the nonlinear simulation model. The nonlinear simulation model developed must be able to simulate the actual UAV flight dynamics accurately for real-time simulation and robust control design purposes. Therefore it is important to include model uncertainties into the nonlinear simulation model developed, especially in small UAV system where its dynamics is less well understood than the full-size aircraft. The second part of the work provides the approach and procedures for uncertainty modeling into the nonlinear simulation model such that realization of linear uncertain model is possible. The third part of work describes the

  1. Latest Advancement In Airborne Relative Gravity Instrumentation.

    NASA Astrophysics Data System (ADS)

    Brady, N.

    2011-12-01

    new system are: - Reduce the size of the system to approximately one third of the volume of the original TAGS and reduce the weight by one half. - Use slip ring technology to eliminate cable drag on the sensor and gimbal platform. - Use a double oven system to further isolate the gravity sensor from large external temperature variations commonly experienced in airborne survey operations. - Completely redesign both the platform control system and data acquisition and recording system to eliminate reliance on standard computer and windows software enhancing reliability and data throughput. - Increase data recording rate to 20 hertz to assist in making GPS corrections to platform levelling. - Use an advanced force feedback system to increase system resolution in turbulent conditions, eliminate dependence on the spring tension counter and the need to clamp the beam during turns. - Enable the system to be used for drape flying and remove the requirement for an operator and hence be suitable for unmanned aerial vehicle (UAV) operations. Prototype testing of the mechanical and electronic components has been ongoing through the first half of 2011. Ground testing and airborne testing began in May of 2011 and will continue through until October of 2011. This paper will present the results of the full hardware testing in different environments and confirmation of the capabilities of the system.

  2. UAV-based NDVI calculation over grassland: An alternative approach

    NASA Astrophysics Data System (ADS)

    Mejia-Aguilar, Abraham; Tomelleri, Enrico; Asam, Sarah; Zebisch, Marc

    2016-04-01

    The Normalised Difference Vegetation Index (NDVI) is one of the most widely used indicators for monitoring and assessing vegetation in remote sensing. The index relies on the reflectance difference between the near infrared (NIR) and red light and is thus able to track variations of structural, phenological, and biophysical parameters for seasonal and long-term monitoring. Conventionally, NDVI is inferred from space-borne spectroradiometers, such as MODIS, with moderate resolution up to 250 m ground resolution. In recent years, a new generation of miniaturized radiometers and integrated hyperspectral sensors with high resolution became available. Such small and light instruments are particularly adequate to be mounted on airborne unmanned aerial vehicles (UAV) used for monitoring services reaching ground sampling resolution in the order of centimetres. Nevertheless, such miniaturized radiometers and hyperspectral sensors are still very expensive and require high upfront capital costs. Therefore, we propose an alternative, mainly cheaper method to calculate NDVI using a camera constellation consisting of two conventional consumer-grade cameras: (i) a Ricoh GR modified camera that acquires the NIR spectrum by removing the internal infrared filter. A mounted optical filter additionally obstructs all wavelengths below 700 nm. (ii) A Ricoh GR in RGB configuration using two optical filters for blocking wavelengths below 600 nm as well as NIR and ultraviolet (UV) light. To assess the merit of the proposed method, we carry out two comparisons: First, reflectance maps generated by the consumer-grade camera constellation are compared to reflectance maps produced with a hyperspectral camera (Rikola). All imaging data and reflectance maps are processed using the PIX4D software. In the second test, the NDVI at specific points of interest (POI) generated by the consumer-grade camera constellation is compared to NDVI values obtained by ground spectral measurements using a

  3. Design of a hybrid rocket / inflatable wing UAV

    NASA Astrophysics Data System (ADS)

    Sudduth, Cory

    This paper discusses the design challenges and development of a UAV that transitions from a rocket, which allows the aircraft to reach a target altitude rapidly, and then deploys an inflatable wing from an enclosed shell in midflight to allow for loitering and surveillance. The wing deployment and transition is tested in static and dynamic environments, while the performance and stability of both the aircraft mode and rocket mode are examined analytically. An in-depth discussion of key components, including the design, analysis and testing, is also included. Designing an UAV that transitions from a high velocity rocket, to a slow velocity UAV provides many difficult and unique design challenges. For example, the incorporation of deployable wing technology into a full UAV system results in many design constraints. In this particular design inflatable wings are used to generate lift during aircraft mode, and the stabilizing fins for the main wing also acted as the fins for the vehicle during its rocket phase. This required the balancing of the two different vehicle configurations to ensure that the aircraft would be able to fly stably in both modes, and transition between them without catastrophic failure. Significant research, and testing went into the finding the best method of storing the inflatable wing, as well as finding the required inflation rate to minimize unsteady aerodynamic affects. Design work was also invested in the development of an inflation system, as it had to be highly reliable, and yet very light weight for use in this small UAV. This paper discusses how these design challenges were overcome, the development and testing of individual sub-components and how they are incorporated into the overall vehicle. The analysis that went into this UAV, as well as methods used to optimize the design in order to minimize weight and maximize the aircraft performance and loitering time is also discussed.

  4. Precision wildlife monitoring using unmanned aerial vehicles

    PubMed Central

    Hodgson, Jarrod C.; Baylis, Shane M.; Mott, Rowan; Herrod, Ashley; Clarke, Rohan H.

    2016-01-01

    Unmanned aerial vehicles (UAVs) represent a new frontier in environmental research. Their use has the potential to revolutionise the field if they prove capable of improving data quality or the ease with which data are collected beyond traditional methods. We apply UAV technology to wildlife monitoring in tropical and polar environments and demonstrate that UAV-derived counts of colony nesting birds are an order of magnitude more precise than traditional ground counts. The increased count precision afforded by UAVs, along with their ability to survey hard-to-reach populations and places, will likely drive many wildlife monitoring projects that rely on population counts to transition from traditional methods to UAV technology. Careful consideration will be required to ensure the coherence of historic data sets with new UAV-derived data and we propose a method for determining the number of duplicated (concurrent UAV and ground counts) sampling points needed to achieve data compatibility. PMID:26986721

  5. Precision wildlife monitoring using unmanned aerial vehicles.

    PubMed

    Hodgson, Jarrod C; Baylis, Shane M; Mott, Rowan; Herrod, Ashley; Clarke, Rohan H

    2016-03-17

    Unmanned aerial vehicles (UAVs) represent a new frontier in environmental research. Their use has the potential to revolutionise the field if they prove capable of improving data quality or the ease with which data are collected beyond traditional methods. We apply UAV technology to wildlife monitoring in tropical and polar environments and demonstrate that UAV-derived counts of colony nesting birds are an order of magnitude more precise than traditional ground counts. The increased count precision afforded by UAVs, along with their ability to survey hard-to-reach populations and places, will likely drive many wildlife monitoring projects that rely on population counts to transition from traditional methods to UAV technology. Careful consideration will be required to ensure the coherence of historic data sets with new UAV-derived data and we propose a method for determining the number of duplicated (concurrent UAV and ground counts) sampling points needed to achieve data compatibility.

  6. Precision wildlife monitoring using unmanned aerial vehicles.

    PubMed

    Hodgson, Jarrod C; Baylis, Shane M; Mott, Rowan; Herrod, Ashley; Clarke, Rohan H

    2016-01-01

    Unmanned aerial vehicles (UAVs) represent a new frontier in environmental research. Their use has the potential to revolutionise the field if they prove capable of improving data quality or the ease with which data are collected beyond traditional methods. We apply UAV technology to wildlife monitoring in tropical and polar environments and demonstrate that UAV-derived counts of colony nesting birds are an order of magnitude more precise than traditional ground counts. The increased count precision afforded by UAVs, along with their ability to survey hard-to-reach populations and places, will likely drive many wildlife monitoring projects that rely on population counts to transition from traditional methods to UAV technology. Careful consideration will be required to ensure the coherence of historic data sets with new UAV-derived data and we propose a method for determining the number of duplicated (concurrent UAV and ground counts) sampling points needed to achieve data compatibility. PMID:26986721

  7. Airborne laser systems for atmospheric sounding in the near infrared

    NASA Astrophysics Data System (ADS)

    Sabatini, Roberto; Richardson, Mark A.; Jia, Huamin; Zammit-Mangion, David

    2012-06-01

    This paper presents new techniques for atmospheric sounding using Near Infrared (NIR) laser sources, direct detection electro-optics and passive infrared imaging systems. These techniques allow a direct determination of atmospheric extinction and, through the adoption of suitable inversion algorithms, the indirect measurement of some important natural and man-made atmospheric constituents, including Carbon Dioxide (CO2). The proposed techniques are suitable for remote sensing missions performed by using aircraft, satellites, Unmanned Aerial Vehicles (UAV), parachute/gliding vehicles, Roving Surface Vehicles (RSV), or Permanent Surface Installations (PSI). The various techniques proposed offer relative advantages in different scenarios. All are based on measurements of the laser energy/power incident on target surfaces of known geometric and reflective characteristics, by means of infrared detectors and/or infrared cameras calibrated for radiance. Experimental results are presented relative to ground and flight trials performed with laser systems operating in the near infrared (NIR) at λ = 1064 nm and λ = 1550 nm. This includes ground tests performed with 10 Hz and 20 KHz PRF NIR laser systems in a variety of atmospheric conditions, and flight trials performed with a 10 Hz airborne NIR laser system installed on a TORNADO aircraft, flying up to altitudes of 22,000 ft above ground level. Future activities are planned to validate the atmospheric retrieval algorithms developed for CO2 column density measurements, with emphasis on aircraft related emissions at airports and other high air-traffic density environments.

  8. Unmanned Aerospace Vehicle Workshop

    SciTech Connect

    Vitko, J. Jr.

    1995-04-01

    The Unmanned Aerospace Vehicle (UAV) Workshop concentrated on reviewing and refining the science experiments planned for the UAV Demonstration Flights (UDF) scheduled at the Oklahoma Cloud and Radiation Testbed (CART) in April 1994. These experiments were focused around the following sets of parameters: Clear sky, daylight; Clear-sky, night-to-day transition; Clear sky - improve/validate the accuracy of radiative fluxes derived from satellite-based measurements; Daylight, clouds of opportunity; and, Daylight, broken clouds.

  9. Cloud Water Content Sensor for Sounding Balloons and Small UAVs

    NASA Technical Reports Server (NTRS)

    Bognar, John A.

    2009-01-01

    A lightweight, battery-powered sensor was developed for measuring cloud water content, which is the amount of liquid or solid water present in a cloud, generally expressed as grams of water per cubic meter. This sensor has near-zero power consumption and can be flown on standard sounding balloons and small, unmanned aerial vehicles (UAVs). The amount of solid or liquid water is important to the study of atmospheric processes and behavior. Previous sensing techniques relied on strongly heating the incoming air, which requires a major energy input that cannot be achieved on sounding balloons or small UAVs.

  10. Tls Models Generation Assisted by Uav Survey

    NASA Astrophysics Data System (ADS)

    Chiabrando, F.; Di Pietra, V.; Lingua, A.; Maschio, P.; Noardo, F.; Sammartano, G.; Spanò, A.

    2016-06-01

    (TLS, Terrestrial Laser Scanning), and large scale mapping derived by UAV (Unmanned Aerial Vehicle) survey. This paper refers an example of 3D survey and reality based modelling applied on landscape and architectural assets. The choice of methods for documentation, in terms of survey techniques, depends primarily on issues and features of the area. The achieved experience, allow to consider that the easy handling of TLS has enabled the use in limited spaces among buildings and collapsed roofs, but the topographic measure of GCPs (Ground Control Points), neither by total station nor by GPS/RTK technique, was easily feasible. Even more than proving the ability of the integration of TLS and UAV photogrammetry to achieve a multi-source and multi-scale whole model of a village, the experience has been a test to experiment the registration of terrestrial clouds with the support of control points derived by UAV survey and finally, a comparison among different strategies of clouds registration is reported. Analysing for each approach a number of parameters (number of clouds registration, number of needed points, processing time, overall accuracy) the further comparisons have been achieved. The test revealed that it is possible to decrease the large number of terrestrial control points when their determination by topographical measures is difficult, and it is possible to combine the techniques not only for the integration of the final 3Dmodel, but also to solve and make the initial stage of the drafting process more effective.

  11. Prognostics Applied to Electric Propulsion UAV

    NASA Technical Reports Server (NTRS)

    Goebel, Kai; Saha, Bhaskar

    2013-01-01

    Health management plays an important role in operations of UAV. If there is equipment malfunction on critical components, safe operation of the UAV might possibly be compromised. A technology with particular promise in this arena is equipment prognostics. This technology provides a state assessment of the health of components of interest and, if a degraded state has been found, it estimates how long it will take before the equipment will reach a failure threshold, conditional on assumptions about future operating conditions and future environmental conditions. This chapter explores the technical underpinnings of how to perform prognostics and shows an implementation on the propulsion of an electric UAV. A particle filter is shown as the method of choice in performing state assessment and predicting future degradation. The method is then applied to the batteries that provide power to the propeller motors. An accurate run-time battery life prediction algorithm is of critical importance to ensure the safe operation of the vehicle if one wants to maximize in-air time. Current reliability based techniques turn out to be insufficient to manage the use of such batteries where loads vary frequently in uncertain environments.

  12. GPS Remote Sensing Measurements Using Aerosonde UAV

    NASA Technical Reports Server (NTRS)

    Grant, Michael S.; Katzberg, Stephen J.; Lawrence, R. W.

    2005-01-01

    In February 2004, a NASA-Langley GPS Remote Sensor (GPSRS) unit was flown on an Aerosonde unmanned aerial vehicle (UAV) from the Wallops Flight Facility (WFF) in Virginia. Using direct and surface-reflected 1.575 GHz coarse acquisition (C/A) coded GPS signals, remote sensing measurements were obtained over land and portions of open water. The strength of the surface-reflected GPS signal is proportional to the amount of moisture in the surface, and is also influenced by surface roughness. Amplitude and other characteristics of the reflected signal allow an estimate of wind speed over open water. In this paper we provide a synopsis of the instrument accommodation requirements, installation procedures, and preliminary results from what is likely the first-ever flight of a GPS remote sensing instrument on a UAV. The correct operation of the GPSRS unit on this flight indicates that Aerosonde-like UAV's can serve as platforms for future GPS remote sensing science missions.

  13. Comparison of Digital Surface Models for Snow Depth Mapping with Uav and Aerial Cameras

    NASA Astrophysics Data System (ADS)

    Boesch, R.; Bühler, Y.; Marty, M.; Ginzler, C.

    2016-06-01

    Photogrammetric workflows for aerial images have improved over the last years in a typically black-box fashion. Most parameters for building dense point cloud are either excessive or not explained and often the progress between software releases is poorly documented. On the other hand, development of better camera sensors and positional accuracy of image acquisition is significant by comparing product specifications. This study shows, that hardware evolutions over the last years have a much stronger impact on height measurements than photogrammetric software releases. Snow height measurements with airborne sensors like the ADS100 and UAV-based DSLR cameras can achieve accuracies close to GSD * 2 in comparison with ground-based GNSS reference measurements. Using a custom notch filter on the UAV camera sensor during image acquisition does not yield better height accuracies. UAV based digital surface models are very robust. Different workflow parameter variations for ADS100 and UAV camera workflows seem to have only random effects.

  14. Multi-eye input experiments for UAV image navigation and control

    NASA Astrophysics Data System (ADS)

    Baer, Wolfgang

    2010-04-01

    Real time Unmanned Arial Vehicle (UAV) image registration is achieved by stimulating one eye with a live video image from a flying UAV while stimulating the other eye with calculated images. The calculated image is initialized by telemetry signals from the UAV and corrected using the Perspective View Nascent Technology (PVNT) software package model-image feedback algorithm. Live and registered calculated images are superimposed allowing command functions including target geo-location, UAV sensor slewing, tracking, and way point flight control. When the same equipment is used with the naked eye the forward observer function can be implemented to produce accurate target coordinates. The paper will then discuss UAV mission control and forward observer target tracking experiments conducted at Camp Roberts, California.

  15. Accuracy analysis of direct georeferenced UAV images utilising low-cost navigation sensors

    NASA Astrophysics Data System (ADS)

    Briese, Christian; Wieser, Martin; Verhoeven, Geert; Glira, Philipp; Doneus, Michael; Pfeifer, Norbert

    2014-05-01

    Unmanned aerial vehicles (UAVs), also known as unmanned airborne systems (UAS) or remotely piloted airborne systems (RPAS), are an established platform for close range airborne photogrammetry. Compared to manned platforms, the acquisition of local remote sensing data by UAVs is a convenient and very flexible option. For the application in photogrammetry UAVs are typically equipped with an autopilot and a lightweight digital camera. The autopilot includes several navigation sensors, which might allow an automated waypoint flight and offer a systematic data acquisition of the object resp. scene of interest. Assuming a sufficient overlap between the captured images, the position (3 coordinates: x, y, z) and the orientation (3 angles: roll, pitch, yaw) of the images can be estimated within a bundle block adjustment. Subsequently, coordinates of observed points that appear in at least two images, can be determined by measuring their image coordinates or a dense surface model can be generated from all acquired images by automated image matching. For the bundle block adjustment approximate values of the position and the orientation of the images are needed. To gather this information, several methods exist. We introduce in this contribution one of them: the direct georeferencing of images by using the navigation sensors (mainly GNSS and INS) of a low-cost on-board autopilot. Beside automated flights, the autopilot offers the possibility to record the position and the orientation of the platform during the flight. These values don't correspond directly to those of the images. To compute the position and the orientation of the images two requirements must be fulfilled. First the misalignment angles and the positional differences between the camera and the autopilot must be determined (mounting calibration). Second the synchronization between the camera and the autopilot has to be established. Due to the limited accuracy of the navigation sensors, a small number of ground

  16. Uav Application in POST - Seismic Environment

    NASA Astrophysics Data System (ADS)

    Baiocchi, V.; Dominici, D.; Mormile, M.

    2013-08-01

    On April 6, 2009, an earthquake of 6.3 magnitude struck central Italy with its epicentre near L'Aquila, at 42.3502° N, 13.3762° E. The earthquake damaged 3000 to 11 000 buildings in the medieval city of L'Aquila. Several buildings totally collapsed, 308 people were killed. The post emergency phase till now is just at its beginning step. Conventional surveying techniques using high precision total stations, GNSS receivers and laser scanners for investigations on damaged buildings are always becoming more automated, accurate and operative and even much more fast. Even if these techniques represent instruments of extreme operability there are still many evident limits on their use, especially regarding the survey of both the roofs and the facades of tall buildings or dangerous places, typical on post earthquake situations. So using micro UAVs for surveying in such particular cases, many of these problems can be easily bypassed. In fact, the present work aims on experimenting using multi-rotor micro UAVs, that will allow high quality image capturing on roofs and facades of structures in the old city center of L'Aquila. To obtain actual stereoscopic acquisitions of buildings some conditions on the geometry of acquisition have to be observed, for this reason, taking as a guideline classic flight photogrammetric, a flight planning software was developed. Accurate planning for UAVs acquisitions is very important also considering the reduced autonomy of such vehicles. This can be a strategic point if we want to use UAVs for early damage assessment and also for post event reconstruction planning.

  17. Swarms of UAVs and fighter aircraft

    SciTech Connect

    Trahan, M.W.; Wagner, J.S.; Stantz, K.M.; Gray, P.C.; Robinett, R.

    1998-11-01

    This paper describes a method of modeling swarms of UAVs and/or fighter aircraft using particle simulation concepts. Recent investigations into the use of genetic algorithms to design neural networks for the control of autonomous vehicles (i.e., robots) led to the examination of methods of simulating large collections of robots. This paper describes the successful implementation of a model of swarm dynamics using particle simulation concepts. Several examples of the complex behaviors achieved in a target/interceptor scenario are presented.

  18. X-Band Radar for Studies of Tropical Storms from High Altitude UAV Platform

    NASA Technical Reports Server (NTRS)

    Rodriquez, Shannon; Heymsfield, Gerald; Li, Lihua; Bradley, Damon

    2007-01-01

    The increased role of unmanned aerial vehicles (UAV) in NASA's suborbital program has created a strong interest in the development of instruments with new capabilities, more compact sizes and reduced weights than the instruments currently operated on manned aircrafts. There is a strong demand and tremendous potential for using high altitude UAV (HUAV) to carry weather radars for measurements of reflectivity and wind fields from tropical storms. Tropical storm genesis frequently occurs in ocean regions that are inaccessible to piloted aircraft due to the long off shore range and the required periods of time to gather significant data. Important factors of interest for the study of hurricane genesis include surface winds, profiled winds, sea surface temperatures, precipitation, and boundary layer conditions. Current satellite precipitation and surface wind sensors have resolutions that are too large and revisit times that are too infrequent to study this problem. Furthermore, none of the spaceborne sensors measure winds within the storm itself. A dual beam X-band Doppler radar, UAV Radar (URAD), is under development at the NASA Goddard Space Flight Center for the study of tropical storms from HUAV platforms, such as a Global Hawk. X-band is the most desirable frequency for airborne weather radars since these can be built in a relatively compact size using off-the-shelf components which cost significantly less than other higher frequency radars. Furthermore, X-band radars provide good sensitivity with tolerable attenuation in storms. The low-cost and light-weight URAD will provide new capabilities for studying hurricane genesis by analyzing the vertical structure of tropical cyclones as well as 3D reflectivity and wind fields in clouds. It will enable us to measure both the 3D precipitation structure and surface winds by using two antenna beams: fixed nadir and conical scanning each produced by its associated subsystem. The nadir subsystem is a magnetron based radar

  19. Establishing a disruptive new capability for NASA to fly UAV's into hazardous conditions

    NASA Astrophysics Data System (ADS)

    Ely, Jay; Nguyen, Truong; Wilson, Jennifer; Brown, Robert; Laughter, Sean; Teets, Ed; Parker, Allen; Chan, Hon M.; Richards, Lance

    2015-05-01

    A 2015 NASA Aeronautics Mission "Seedling" Proposal is described for a Severe-Environment UAV (SE-UAV) that can perform in-situ measurements in hazardous atmospheric conditions like lightning, volcanic ash and radiation. Specifically, this paper describes the design of a proof-of-concept vehicle and measurement system that can survive lightning attachment during flight operations into thunderstorms. Elements from three NASA centers draw together for the SE-UAV concept. 1) The NASA KSC Genesis UAV was developed in collaboration with the DARPA Nimbus program to measure electric field and X-rays present within thunderstorms. 2) A novel NASA LaRC fiber-optic sensor uses Faraday-effect polarization rotation to measure total lightning electric current on an air vehicle fuselage. 3) NASA AFRC's state-of-the-art Fiber Optics and Systems Integration Laboratory is envisioned to transition the Faraday system to a compact, light-weight, all-fiber design. The SE-UAV will provide in-flight lightning electric-current return stroke and recoil leader data, and serve as a platform for development of emerging sensors and new missions into hazardous environments. NASA's Aeronautics and Science Missions are interested in a capability to perform in-situ volcanic plume measurements and long-endurance UAV operations in various weather conditions. (Figure 1 shows an artist concept of a SE-UAV flying near a volcano.) This paper concludes with an overview of the NASA Aeronautics Strategic Vision, Programs, and how a SE-UAV is envisioned to impact them. The SE-UAV concept leverages high-value legacy research products into a new capability for NASA to fly a pathfinder UAV into hazardous conditions, and is presented in the SPIE DSS venue to explore teaming, collaboration and advocacy opportunities outside NASA.

  20. Establishing a Disruptive New Capability for NASA to Fly UAV's into Hazardous Conditions

    NASA Technical Reports Server (NTRS)

    Ely, Jay; Nguyen, Truong; Wilson, Jennifer; Brown, Robert; Laughter, Sean; Teets, Ed; Parker, Allen; Chan, Patrick Hon Man; Richards, Lance

    2015-01-01

    A 2015 NASA Aeronautics Mission "Seedling" Proposal is described for a Severe-Environment UAV (SE-UAV) that can perform in-situ measurements in hazardous atmospheric conditions like lightning, volcanic ash and radiation. Specifically, this paper describes the design of a proof-of-concept vehicle and measurement system that can survive lightning attachment during flight operations into thunderstorms. Elements from three NASA centers draw together for the SE-UAV concept. 1) The NASA KSC Genesis UAV was developed in collaboration with the DARPA Nimbus program to measure electric field and X-rays present within thunderstorms. 2) A novel NASA LaRC fiber-optic sensor uses Faraday-effect polarization rotation to measure total lightning electric current on an air vehicle fuselage. 3) NASA AFRC's state-of-the-art Fiber Optics and Systems Integration Laboratory is envisioned to transition the Faraday system to a compact, light-weight, all-fiber design. The SE-UAV will provide in-flight lightning electric-current return stroke and recoil leader data, and serve as a platform for development of emerging sensors and new missions into hazardous environments. NASA's Aeronautics and Science Missions are interested in a capability to perform in-situ volcanic plume measurements and long-endurance UAV operations in various weather conditions. (Figure 1 shows an artist concept of a SE-UAV flying near a volcano.) This paper concludes with an overview of the NASA Aeronautics Strategic Vision, Programs, and how a SE-UAV is envisioned to impact them. The SE-UAV concept leverages high-value legacy research products into a new capability for NASA to fly a pathfinder UAV into hazardous conditions, and is presented in the SPIE DSS venue to explore teaming, collaboration and advocacy opportunities outside NASA.

  1. 3D model generation using an airborne swarm

    NASA Astrophysics Data System (ADS)

    Clark, R. A.; Punzo, G.; Dobie, G.; MacLeod, C. N.; Summan, R.; Pierce, G.; Macdonald, M.; Bolton, G.

    2015-03-01

    Using an artificial kinematic field to provide co-ordination between multiple inspection UAVs, the authors herein demonstrate full 3D modelling capability based on a photogrammetric system. The operation of the system is demonstrated by generating a full 3D surface model of an intermediate level nuclear waste storage drum. Such drums require periodic inspection to ensure that drum distortion or corrosion is carefully monitored. Performing this inspection with multiple airborne platforms enables rapid inspection of structures that are inaccessible to on-surface remote vehicles and are in human-hazardous environments. A three-dimensional surface-meshed model of the target can then be constructed in post-processing through photogrammetry analysis of the visual inspection data. The inspection environment uses a tracking system to precisely monitor the position of each aerial vehicle within the enclosure. The vehicles used are commercially available Parrot AR. Drone quadcopters, controlled through a computer interface connected over an IEEE 802.11n (WiFi) network, implementing a distributed controller for each vehicle. This enables the autonomous and distributed elements of the control scheme to be retained, while alleviating the vehicles of the control algorithm's computational load. The control scheme relies on a kinematic field defined with the target at its centre. This field defines the trajectory for all the drones in the volume relative to the central target, enabling the drones to circle the target at a set radius while avoiding drone collisions. This function enables complete coverage along the height of the object, which is assured by transitioning to another inspection band only after completing circumferential coverage. Using a swarm of vehicles, the time until complete coverage can be significantly reduced.

  2. 3D model generation using an airborne swarm

    SciTech Connect

    Clark, R. A.; Punzo, G.; Macdonald, M.; Dobie, G.; MacLeod, C. N.; Summan, R.; Pierce, G.; Bolton, G.

    2015-03-31

    Using an artificial kinematic field to provide co-ordination between multiple inspection UAVs, the authors herein demonstrate full 3D modelling capability based on a photogrammetric system. The operation of the system is demonstrated by generating a full 3D surface model of an intermediate level nuclear waste storage drum. Such drums require periodic inspection to ensure that drum distortion or corrosion is carefully monitored. Performing this inspection with multiple airborne platforms enables rapid inspection of structures that are inaccessible to on-surface remote vehicles and are in human-hazardous environments. A three-dimensional surface-meshed model of the target can then be constructed in post-processing through photogrammetry analysis of the visual inspection data. The inspection environment uses a tracking system to precisely monitor the position of each aerial vehicle within the enclosure. The vehicles used are commercially available Parrot AR. Drone quadcopters, controlled through a computer interface connected over an IEEE 802.11n (WiFi) network, implementing a distributed controller for each vehicle. This enables the autonomous and distributed elements of the control scheme to be retained, while alleviating the vehicles of the control algorithm’s computational load. The control scheme relies on a kinematic field defined with the target at its centre. This field defines the trajectory for all the drones in the volume relative to the central target, enabling the drones to circle the target at a set radius while avoiding drone collisions. This function enables complete coverage along the height of the object, which is assured by transitioning to another inspection band only after completing circumferential coverage. Using a swarm of vehicles, the time until complete coverage can be significantly reduced.

  3. Applications of UAVs for Remote Sensing of Critical Infrastructure

    NASA Technical Reports Server (NTRS)

    Wegener, Steve; Brass, James; Schoenung, Susan

    2003-01-01

    The surveillance of critical facilities and national infrastructure such as waterways, roadways, pipelines and utilities requires advanced technological tools to provide timely, up to date information on structure status and integrity. Unmanned Aerial Vehicles (UAVs) are uniquely suited for these tasks, having large payload and long duration capabilities. UAVs also have the capability to fly dangerous and dull missions, orbiting for 24 hours over a particular area or facility providing around the clock surveillance with no personnel onboard. New UAV platforms and systems are becoming available for commercial use. High altitude platforms are being tested for use in communications, remote sensing, agriculture, forestry and disaster management. New payloads are being built and demonstrated onboard the UAVs in support of these applications. Smaller, lighter, lower power consumption imaging systems are currently being tested over coffee fields to determine yield and over fires to detect fire fronts and hotspots. Communication systems that relay video, meteorological and chemical data via satellite to users on the ground in real-time have also been demonstrated. Interest in this technology for infrastructure characterization and mapping has increased dramatically in the past year. Many of the UAV technological developments required for resource and disaster monitoring are being used for the infrastructure and facility mapping activity. This paper documents the unique contributions from NASA;s Environmental Research Aircraft and Sensor Technology (ERAST) program to these applications. ERAST is a UAV technology development effort by a consortium of private aeronautical companies and NASA. Details of demonstrations of UAV capabilities currently underway are also presented.

  4. Collaborative mission planning for UAV cluster to optimize relay distance

    NASA Astrophysics Data System (ADS)

    Tanil, Cagatay; Warty, Chirag; Obiedat, Esam

    Unmanned Aerial Vehicles (UAVs) coordinated path planning and intercommunication for visual exploration of a geographical region has recently become crucial. Multiple UAVs cover larger area than a single UAV and eliminate blind spots. To improve the surveillance, survivability and quality of the communication, we propose two algorithms for the route planning of UAV cluster operated in obstacle rich environment: (i) Multiple Population Genetic Algorithm (MPGA) (ii) Relay Selection Criteria (RSC). The main objective of MPGA is to minimize the total mission time while maintaining an optimal distance for communication between the neighboring nodes. MPGA utilizes evolutionary speciation techniques with a novel Feasible Population Creation Method (FPCM) and enhanced Inter-species Crossover Mechanism (ISCM) to obtain diversified routes in remarkably short time. In obtaining collision-free optimum paths, UAVs are subjected to constraints such as limited communication range, maximum maneuverability and fuel capacity. In addition to the path planning, RSC is developed for selection of UAVs relay nodes that is based on the location of the relay relative to source and destination. It is crucial since the Bit Error Rate (BER) performance of the link significantly depends on the location of the selected relay. In this paper, path planning and relay allocation algorithms are combined to have a seamless high quality monitoring of the region and to provide superior Quality of Service (QoS) for audio-video applications. Also, simulations in different operation zones with a cluster of up to six UAVs are performed to verify the feasibility of the proposed algorithms both in optimality and computation time.

  5. Low cost infrared and near infrared sensors for UAVs

    NASA Astrophysics Data System (ADS)

    Aden, S. T.; Bialas, J. P.; Champion, Z.; Levin, E.; McCarty, J. L.

    2014-11-01

    Thermal remote sensing has a wide range of applications, though the extent of its use is inhibited by cost. Robotic and computer components are now widely available to consumers on a scale that makes thermal data a readily accessible resource. In this project, thermal imagery collected via a lightweight remote sensing Unmanned Aerial Vehicle (UAV) was used to create a surface temperature map for the purpose of providing wildland firefighting crews with a cost-effective and time-saving resource. The UAV system proved to be flexible, allowing for customized sensor packages to be designed that could include visible or infrared cameras, GPS, temperature sensors, and rangefinders, in addition to many data management options. Altogether, such a UAV system could be used to rapidly collect thermal and aerial data, with a geographic accuracy of less than one meter.

  6. Electric Power System for High Altitude UAV Technology Survey

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Electric powertrain technologies with application to high altitude Unmanned Aerial Vehicles (UAV) are assessed. One hundred twenty five solar electric UAV configurations and missions were simulated. Synergistic design opportunities were investigated with the premise that specific benefits may be realized, for example, if a single component can serve multiple functions, such as a battery being used for energy storage as well as for a structural component of the aircraft. For each UAV mission simulation, the airframe structure, powertrain configuration (type of solar cells, energy storage options) and performance baseline (1997 or 2001) were specified. It has been found that the use of the high efficiency (multijunction) solar cells or the use of the synergistic amorphous silicon solar cell configuration yields aircraft that can accomplish the majority of the missions of interest for any latitude between 0 deg and 55 deg, hence, a single versatile aircraft can be constructed and implemented to accomplish these missions.

  7. Uav Photogrammetry: a Practical Solution for Challenging Mapping Projects

    NASA Astrophysics Data System (ADS)

    Saadatseresht, M.; Hashempour, A. H.; Hasanlou, M.

    2015-12-01

    We have observed huge attentions to application of unmanned aerial vehicle (UAV) in aerial mapping since a decade ago. Though, it has several advantages for handling time/cost/quality issues, there are a dozen of challenges in working with UAVs. In this paper, we; as the Robotic Photogrammetry Research Group (RPRG), will firstly review these challenges then show its advantages in three special practical projects. For each project, we will share our experiences through description of the UAV specifications, flight settings and processing steps. At the end, we will illustrate final result of each project and show how this technology could make unbelievable benefits to clients including 3D city realistic model in decimetre level, ultra high quality map production in several centimetre level, and accessing to a high risk and rough relief area for mapping aims.

  8. Autonomous mission management for UAVs using soar intelligent agents

    NASA Astrophysics Data System (ADS)

    Gunetti, Paolo; Thompson, Haydn; Dodd, Tony

    2013-05-01

    State-of-the-art unmanned aerial vehicles (UAVs) are typically able to autonomously execute a pre-planned mission. However, UAVs usually fly in a very dynamic environment which requires dynamic changes to the flight plan; this mission management activity is usually tasked to human supervision. Within this article, a software system that autonomously accomplishes the mission management task for a UAV will be proposed. The system is based on a set of theoretical concepts which allow the description of a flight plan and implemented using a combination of Soar intelligent agents and traditional control techniques. The system is capable of automatically generating and then executing an entire flight plan after being assigned a set of objectives. This article thoroughly describes all system components and then presents the results of tests that were executed using a realistic simulation environment.

  9. Automatic target detection in UAV imagery using image formation conditions

    NASA Astrophysics Data System (ADS)

    Lin, Huibao; Si, Jennie; Abousleman, Glen P.

    2003-09-01

    This paper is about automatic target detection (ATD) in unmanned aerial vehicle (UAV) imagery. Extracting reliable features under all conditions from a 2D projection of a target in UAV imagery is a difficult problem. However, since the target size information is usually invariant to the image formation proces, we propose an algorithm for automatically estimating the size of a 3D target by using its 2D projection. The size information in turn becomes an important feature to be used in a knowledge-driven, multi-resolution-based algorithm for automatically detecting targets in UAV imagery. Experimental results show that our proposed ATD algorithm provides outstanding detection performance, while significantly reducing the false alarm rate and the computational complexity.

  10. UAV-based Radar Sounding of Antarctic Ice

    NASA Astrophysics Data System (ADS)

    Leuschen, Carl; Yan, Jie-Bang; Mahmood, Ali; Rodriguez-Morales, Fernando; Hale, Rick; Camps-Raga, Bruno; Metz, Lynsey; Wang, Zongbo; Paden, John; Bowman, Alec; Keshmiri, Shahriar; Gogineni, Sivaprasad

    2014-05-01

    We developed a compact radar for use on a small UAV to conduct measurements over the ice sheets in Greenland and Antarctica. It operates at center frequencies of 14 and 35 MHz with bandwidths of 1 MHz and 4 MHz, respectively. The radar weighs about 2 kgs and is housed in a box with dimensions of 20.3 cm x 15.2 cm x 13.2 cm. It transmits a signal power of 100 W at a pulse repletion frequency of 10 kHz and requires average power of about 20 W. The antennas for operating the radar are integrated into the wings and airframe of a small UAV with a wingspan of 5.3 m. We selected the frequencies of 14 and 35 MHz based on previous successful soundings of temperate ice in Alaska with a 12.5 MHz impulse radar [Arcone, 2002] and temperate glaciers in Patagonia with a 30 MHz monocycle radar [Blindow et al., 2012]. We developed the radar-equipped UAV to perform surveys over a 2-D grid, which allows us to synthesize a large two-dimensional aperture and obtain fine resolution in both the along- and cross-track directions. Low-frequency, high-sensitivity radars with 2-D aperture synthesis capability are needed to overcome the surface and volume scatter that masks weak echoes from the ice-bed interface of fast-flowing glaciers. We collected data with the radar-equipped UAV on sub-glacial ice near Lake Whillans at both 14 and 35 MHz. We acquired data to evaluate the concept of 2-D aperture synthesis and successfully demonstrated the first successful sounding of ice with a radar on an UAV. We are planning to build multiple radar-equipped UAVs for collecting fine-resolution data near the grounding lines of fast-flowing glaciers. In this presentation we will provide a brief overview of the radar and UAV, as well as present results obtained at both 14 and 35 MHz. Arcone, S. 2002. Airborne-radar stratigraphy and electrical structure of temperate firn: Bagley Ice Field, Alaska, U.S.A. Journal of Glaciology, 48, 317-334. Blindow, N., C. Salat, and G. Casassa. 2012. Airborne GPR sounding of

  11. An Application of UAV Attitude Estimation Using a Low-Cost Inertial Navigation System

    NASA Technical Reports Server (NTRS)

    Eure, Kenneth W.; Quach, Cuong Chi; Vazquez, Sixto L.; Hogge, Edward F.; Hill, Boyd L.

    2013-01-01

    Unmanned Aerial Vehicles (UAV) are playing an increasing role in aviation. Various methods exist for the computation of UAV attitude based on low cost microelectromechanical systems (MEMS) and Global Positioning System (GPS) receivers. There has been a recent increase in UAV autonomy as sensors are becoming more compact and onboard processing power has increased significantly. Correct UAV attitude estimation will play a critical role in navigation and separation assurance as UAVs share airspace with civil air traffic. This paper describes attitude estimation derived by post-processing data from a small low cost Inertial Navigation System (INS) recorded during the flight of a subscale commercial off the shelf (COTS) UAV. Two discrete time attitude estimation schemes are presented here in detail. The first is an adaptation of the Kalman Filter to accommodate nonlinear systems, the Extended Kalman Filter (EKF). The EKF returns quaternion estimates of the UAV attitude based on MEMS gyro, magnetometer, accelerometer, and pitot tube inputs. The second scheme is the complementary filter which is a simpler algorithm that splits the sensor frequency spectrum based on noise characteristics. The necessity to correct both filters for gravity measurement errors during turning maneuvers is demonstrated. It is shown that the proposed algorithms may be used to estimate UAV attitude. The effects of vibration on sensor measurements are discussed. Heuristic tuning comments pertaining to sensor filtering and gain selection to achieve acceptable performance during flight are given. Comparisons of attitude estimation performance are made between the EKF and the complementary filter.

  12. UAV formation control design with obstacle avoidance in dynamic three-dimensional environment.

    PubMed

    Chang, Kai; Xia, Yuanqing; Huang, Kaoli

    2016-01-01

    This paper considers the artificial potential field method combined with rotational vectors for a general problem of multi-unmanned aerial vehicle (UAV) systems tracking a moving target in dynamic three-dimensional environment. An attractive potential field is generated between the leader and the target. It drives the leader to track the target based on the relative position of them. The other UAVs in the formation are controlled to follow the leader by the attractive control force. The repulsive force affects among the UAVs to avoid collisions and distribute the UAVs evenly on the spherical surface whose center is the leader-UAV. Specific orders or positions of the UAVs are not required. The trajectories of avoidance obstacle can be obtained through two kinds of potential field with rotation vectors. Every UAV can choose the optimal trajectory to avoid the obstacle and reconfigure the formation after passing the obstacle. Simulations study on UAV are presented to demonstrate the effectiveness of proposed method. PMID:27478741

  13. Improving automatic cooperation between UAVs through co-evolution

    NASA Astrophysics Data System (ADS)

    Smith, James F., III

    2008-04-01

    A fuzzy logic resource manager (RM) that enables a collection of unmanned aerial vehicles (UAVs) to automatically cooperate to make meteorological measurements will be discussed. The RM renders the UAVs autonomous allowing them to change paths and cooperate without human intervention. Innovations related to the "priority for helping" (PH) fuzzy decision tree (FDT) used by the RM will be discussed. The PH FDT permits three types of automatic cooperation between the UAVs. A subroutine of the communications routing algorithm (CRA) used by the RM is also examined. The CRA allows the UAVs to reestablish communications if needed by changing their behavior. A genetic program (GP) based procedure for automatically creating FDTs is briefly described. A GP is an algorithm based on the theory of evolution that automatically evolves mathematical expressions or computer algorithms. The GP data mines a scenario database to automatically create the FDTs. A recently invented co-evolutionary process that allows improvement of the initially data mined FDT will be discussed. Co-evolution uses a genetic algorithm (GA) to evolve scenarios to augment the GP's scenario database. The GP data mines the augmented database to discover an improved FDT. The process is iterated ultimately evolving a very robust FDT. Improvements to the PH FDT offered through co-evolution are discussed. UAV simulations using the improved PH FDT and CRA are provided.

  14. A Behavior Based Control System for Surveillance UAVs

    NASA Astrophysics Data System (ADS)

    Oyekan, John; Lu, Bowen; Li, Bo; Gu, Dongbing; Hu, Huosheng

    Unmanned Aerial Vehicles (UAVs) is required to carry out duties such as surveillance, reconnaissance, search and rescue and security patrol missions. Autonomous operation of UAVs is a key to the success of these missions. In this chapter, we propose to use a behavior based control architecture to implement autonomous operation for UAV surveillance missions. This control architecture consists of two layers: a low level control layer and a behavior layer. The low level control layer decomposes 3D motion of UAVs into several atomic actions, such as yaw, roll, pitch, altitude, and 2D position control. These atomic actions together serve as a basis for the behavior layer. The behavior layer consists of a number of necessary behaviors used for surveillance missions, including take-off, object tracking, hovering, landing, trajectory following, obstacle avoidance amongst other behaviors. These behaviors can be instantiated individually or collectively to fulfill the required missions issued by human operators. To evaluate the proposed control architecture, the commercially available DraganFlyer QuadRotor was used as the UAV platform. With the aid of an indoor positioning system, several atomic actions and a group of behaviors were developed for the DraganFlyer. Real testing experiments were conducted to demonstrate the feasibility and performance of the proposed system.

  15. Sense and avoid technology for Global Hawk and Predator UAVs

    NASA Astrophysics Data System (ADS)

    McCalmont, John F.; Utt, James; Deschenes, Michael; Taylor, Michael J.

    2005-05-01

    The Sensors Directorate at the Air Force Research Laboratory (AFRL) along with Defense Research Associates, Inc. (DRA) conducted a flight demonstration of technology that could potentially satisfy the Federal Aviation Administration's (FAA) requirement for Unmanned Aerial Vehicles (UAVs) to sense and avoid local air traffic sufficient to provide an "...equivalent level of safety, comparable to see-and-avoid requirements for manned aircraft". This FAA requirement must be satisfied for autonomous UAV operation within the national airspace. The real-time on-board system passively detects approaching aircraft, both cooperative and non-cooperative, using imaging sensors operating in the visible/near infrared band and a passive moving target indicator algorithm. Detection range requirements for RQ-4 and MQ-9 UAVs were determined based on analysis of flight geometries, avoidance maneuver timelines, system latencies and human pilot performance. Flight data and UAV operating parameters were provided by the system program offices, prime contractors, and flight-test personnel. Flight demonstrations were conducted using a surrogate UAV (Aero Commander) and an intruder aircraft (Beech Bonanza). The system demonstrated target detection ranges out to 3 nautical miles in nose-to-nose scenarios and marginal visual meteorological conditions. (VMC) This paper will describe the sense and avoid requirements definition process and the system concept (sensors, algorithms, processor, and flight rest results) that has demonstrated the potential to satisfy the FAA sense and avoid requirements.

  16. Reproducibility of UAV-based photogrammetric surface models

    NASA Astrophysics Data System (ADS)

    Anders, Niels; Smith, Mike; Cammeraat, Erik; Keesstra, Saskia

    2016-04-01

    Soil erosion, rapid geomorphological change and vegetation degradation are major threats to the human and natural environment in many regions. Unmanned Aerial Vehicles (UAVs) and Structure-from-Motion (SfM) photogrammetry are invaluable tools for the collection of highly detailed aerial imagery and subsequent low cost production of 3D landscapes for an assessment of landscape change. Despite the widespread use of UAVs for image acquisition in monitoring applications, the reproducibility of UAV data products has not been explored in detail. This paper investigates this reproducibility by comparing the surface models and orthophotos derived from different UAV flights that vary in flight direction and altitude. The study area is located near Lorca, Murcia, SE Spain, which is a semi-arid medium-relief locale. The area is comprised of terraced agricultural fields that have been abandoned for about 40 years and have suffered subsequent damage through piping and gully erosion. In this work we focused upon variation in cell size, vertical and horizontal accuracy, and horizontal positioning of recognizable landscape features. The results suggest that flight altitude has a significant impact on reconstructed point density and related cell size, whilst flight direction affects the spatial distribution of vertical accuracy. The horizontal positioning of landscape features is relatively consistent between the different flights. We conclude that UAV data products are suitable for monitoring campaigns for land cover purposes or geomorphological mapping, but special care is required when used for monitoring changes in elevation.

  17. Development of a UAV system for VNIR-TIR acquisitions in precision agriculture

    NASA Astrophysics Data System (ADS)

    Misopolinos, L.; Zalidis, Ch.; Liakopoulos, V.; Stavridou, D.; Katsigiannis, P.; Alexandridis, T. K.; Zalidis, G.

    2015-06-01

    Adoption of precision agriculture techniques requires the development of specialized tools that provide spatially distributed information. Both flying platforms and airborne sensors are being continuously evolved to cover the needs of plant and soil sensing at affordable costs. Due to restrictions in payload, flying platforms are usually limited to carry a single sensor on board. The aim of this work is to present the development of a vertical take-off and landing autonomous unmanned aerial vehicle (VTOL UAV) system for the simultaneous acquisition of high resolution vertical images at the visible, near infrared (VNIR) and thermal infrared (TIR) wavelengths. A system was developed that has the ability to trigger two cameras simultaneously with a fully automated process and no pilot intervention. A commercial unmanned hexacopter UAV platform was optimized to increase reliability, ease of operation and automation. The designed systems communication platform is based on a reduced instruction set computing (RISC) processor running Linux OS with custom developed drivers in an efficient way, while keeping the cost and weight to a minimum. Special software was also developed for the automated image capture, data processing and on board data and metadata storage. The system was tested over a kiwifruit field in northern Greece, at flying heights of 70 and 100m above the ground. The acquired images were mosaicked and geo-corrected. Images from both flying heights were of good quality and revealed unprecedented detail within the field. The normalized difference vegetation index (NDVI) was calculated along with the thermal image in order to provide information on the accurate location of stressors and other parameters related to the crop productivity. Compared to other available sources of data, this system can provide low cost, high resolution and easily repeatable information to cover the requirements of precision agriculture.

  18. UAV-guided navigation for ground robot tele-operation in a military reconnaissance environment.

    PubMed

    Chen, Jessie Y C

    2010-08-01

    A military reconnaissance environment was simulated to examine the performance of ground robotics operators who were instructed to utilise streaming video from an unmanned aerial vehicle (UAV) to navigate his/her ground robot to the locations of the targets. The effects of participants' spatial ability on their performance and workload were also investigated. Results showed that participants' overall performance (speed and accuracy) was better when she/he had access to images from larger UAVs with fixed orientations, compared with other UAV conditions (baseline- no UAV, micro air vehicle and UAV with orbiting views). Participants experienced the highest workload when the UAV was orbiting. Those individuals with higher spatial ability performed significantly better and reported less workload than those with lower spatial ability. The results of the current study will further understanding of ground robot operators' target search performance based on streaming video from UAVs. The results will also facilitate the implementation of ground/air robots in military environments and will be useful to the future military system design and training community. PMID:20658388

  19. UAV-guided navigation for ground robot tele-operation in a military reconnaissance environment.

    PubMed

    Chen, Jessie Y C

    2010-08-01

    A military reconnaissance environment was simulated to examine the performance of ground robotics operators who were instructed to utilise streaming video from an unmanned aerial vehicle (UAV) to navigate his/her ground robot to the locations of the targets. The effects of participants' spatial ability on their performance and workload were also investigated. Results showed that participants' overall performance (speed and accuracy) was better when she/he had access to images from larger UAVs with fixed orientations, compared with other UAV conditions (baseline- no UAV, micro air vehicle and UAV with orbiting views). Participants experienced the highest workload when the UAV was orbiting. Those individuals with higher spatial ability performed significantly better and reported less workload than those with lower spatial ability. The results of the current study will further understanding of ground robot operators' target search performance based on streaming video from UAVs. The results will also facilitate the implementation of ground/air robots in military environments and will be useful to the future military system design and training community.

  20. Positional quality assessment of orthophotos obtained from sensors onboard multi-rotor UAV platforms.

    PubMed

    Mesas-Carrascosa, Francisco Javier; Rumbao, Inmaculada Clavero; Berrocal, Juan Alberto Barrera; Porras, Alfonso García-Ferrer

    2014-11-26

    In this study we explored the positional quality of orthophotos obtained by an unmanned aerial vehicle (UAV). A multi-rotor UAV was used to obtain images using a vertically mounted digital camera. The flight was processed taking into account the photogrammetry workflow: perform the aerial triangulation, generate a digital surface model, orthorectify individual images and finally obtain a mosaic image or final orthophoto. The UAV orthophotos were assessed with various spatial quality tests used by national mapping agencies (NMAs). Results showed that the orthophotos satisfactorily passed the spatial quality tests and are therefore a useful tool for NMAs in their production flowchart.

  1. Using Uav to Detect Shoreline Changes: Case Study - Pohranov Pond, Czech Republic

    NASA Astrophysics Data System (ADS)

    Čermáková, I.; Komárková, J.; Sedlák, P.

    2016-06-01

    The paper describes utilization of an unmanned aerial vehicle (UAV) for detection of changes of shorelines. UAV is used as a cheep and on-demand available possibility how to collect remotely sensed data. Its utilization is limited by legal regulations and weather conditions. Paper deals with utilization of UAV for monitoring small water area and particularly study of changes of shorelines. Study contains other methods of classification. After classification will be data processed for next calculations. Indices regarding shoreline changes are in the study also. In conclusion, study contains obtainment findings and encouragement for the future.

  2. Positional Quality Assessment of Orthophotos Obtained from Sensors Onboard Multi-Rotor UAV Platforms

    PubMed Central

    Mesas-Carrascosa, Francisco Javier; Rumbao, Inmaculada Clavero; Berrocal, Juan Alberto Barrera; Porras, Alfonso García-Ferrer

    2014-01-01

    In this study we explored the positional quality of orthophotos obtained by an unmanned aerial vehicle (UAV). A multi-rotor UAV was used to obtain images using a vertically mounted digital camera. The flight was processed taking into account the photogrammetry workflow: perform the aerial triangulation, generate a digital surface model, orthorectify individual images and finally obtain a mosaic image or final orthophoto. The UAV orthophotos were assessed with various spatial quality tests used by national mapping agencies (NMAs). Results showed that the orthophotos satisfactorily passed the spatial quality tests and are therefore a useful tool for NMAs in their production flowchart. PMID:25587877

  3. Positional quality assessment of orthophotos obtained from sensors onboard multi-rotor UAV platforms.

    PubMed

    Mesas-Carrascosa, Francisco Javier; Rumbao, Inmaculada Clavero; Berrocal, Juan Alberto Barrera; Porras, Alfonso García-Ferrer

    2014-01-01

    In this study we explored the positional quality of orthophotos obtained by an unmanned aerial vehicle (UAV). A multi-rotor UAV was used to obtain images using a vertically mounted digital camera. The flight was processed taking into account the photogrammetry workflow: perform the aerial triangulation, generate a digital surface model, orthorectify individual images and finally obtain a mosaic image or final orthophoto. The UAV orthophotos were assessed with various spatial quality tests used by national mapping agencies (NMAs). Results showed that the orthophotos satisfactorily passed the spatial quality tests and are therefore a useful tool for NMAs in their production flowchart. PMID:25587877

  4. Autonomous soaring and surveillance in wind fields with an unmanned aerial vehicle

    NASA Astrophysics Data System (ADS)

    Gao, Chen

    Small unmanned aerial vehicles (UAVs) play an active role in developing a low-cost, low-altitude autonomous aerial surveillance platform. The success of the applications needs to address the challenge of limited on-board power plant that limits the endurance performance in surveillance mission. This thesis studies the mechanics of soaring flight, observed in nature where birds utilize various wind patterns to stay airborne without flapping their wings, and investigates its application to small UAVs in their surveillance missions. In a proposed integrated framework of soaring and surveillance, a bird-mimicking soaring maneuver extracts energy from surrounding wind environment that improves surveillance performance in terms of flight endurance, while the surveillance task not only covers the target area, but also detects energy sources within the area to allow for potential soaring flight. The interaction of soaring and surveillance further enables novel energy based, coverage optimal path planning. Two soaring and associated surveillance strategies are explored. In a so-called static soaring surveillance, the UAV identifies spatially-distributed thermal updrafts for soaring, while incremental surveillance is achieved through gliding flight to visit concentric expanding regions. A Gaussian-process-regression-based algorithm is developed to achieve computationally-efficient and smooth updraft estimation. In a so-called dynamic soaring surveillance, the UAV performs one cycle of dynamic soaring to harvest energy from the horizontal wind gradient to complete one surveillance task by visiting from one target to the next one. A Dubins-path-based trajectory planning approach is proposed to maximize wind energy extraction and ensure smooth transition between surveillance tasks. Finally, a nonlinear trajectory tracking controller is designed for a full six-degree-of-freedom nonlinear UAV dynamics model and extensive simulations are carried to demonstrate the effectiveness of

  5. Detection of Verticillium wilt of olive trees and downy mildew of opium poppy using hyperspectral and thermal UAV imagery

    NASA Astrophysics Data System (ADS)

    Calderón Madrid, Rocío; Navas Cortés, Juan Antonio; Montes Borrego, Miguel; Landa del Castillo, Blanca Beatriz; Lucena León, Carlos; Jesús Zarco Tejada, Pablo

    2014-05-01

    The present study explored the use of high-resolution thermal, multispectral and hyperspectral imagery as indicators of the infections caused by Verticillium wilt (VW) in olive trees and downy mildew (DM) in opium poppy fields. VW, caused by the soil-borne fungus Verticillium dahliae, and DM, caused by the biotrophic obligate oomycete Peronospora arborescens, are the most economically limiting diseases of olive trees and opium poppy, respectively, worldwide. V. dahliae infects the plant by the roots and colonizes its vascular system, blocking water flow and eventually inducing water stress. P. arborescens colonizes the mesophyll, appearing the first symptoms as small chlorotic leaf lesions, which can evolve to curled and thickened tissues and systemic infections that become deformed and necrotic as the disease develops. The work conducted to detect VW and DM infection consisted on the acquisition of time series of airborne thermal, multispectral and hyperspectral imagery using 2-m and 5-m wingspan electric Unmanned Aerial Vehicles (UAVs) in spring and summer of three consecutive years (2009 to 2011) for VW detection and on three dates in spring of 2009 for DM detection. Two 7-ha commercial olive orchards naturally infected with V. dahliae and two opium poppy field plots artificially infected by P. arborescens were flown. Concurrently to the airborne campaigns, olive orchards and opium poppy fields were assessed "in situ" to assess actual VW severity and DM incidence. Furthermore, field measurements were conducted at leaf and crown level. The field results related to VW detection showed a significant increase in crown temperature (Tc) minus air temperature (Ta) and a decrease in leaf stomatal conductance (G) as VW severity increased. This reduction in G was associated with a significant increase in the Photochemical Reflectance Index (PRI570) and a decrease in chlorophyll fluorescence. DM asymptomatic leaves showed significantly higher NDVI and lower green/red index

  6. STOMP: A Software Architecture for the Design and Simulation UAV-Based Sensor Networks

    SciTech Connect

    Jones, E D; Roberts, R S; Hsia, T C S

    2002-10-28

    This paper presents the Simulation, Tactical Operations and Mission Planning (STOMP) software architecture and framework for simulating, controlling and communicating with unmanned air vehicles (UAVs) servicing large distributed sensor networks. STOMP provides hardware-in-the-loop capability enabling real UAVs and sensors to feedback state information, route data and receive command and control requests while interacting with other real or virtual objects thereby enhancing support for simulation of dynamic and complex events.

  7. Rangeland resource assessment, monitoring, and management using unmanned aerial vehicle-based remote sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Civilian applications of Unmanned Aerial Vehicles (UAV) have rapidly been expanding recently. Thanks to military development many civil UAVs come via the defense sector. Although numerous UAVs can perform civilian tasks, the regulations imposed by FAA in the national airspace system and military e...

  8. BgCut: automatic ship detection from UAV images.

    PubMed

    Xu, Chao; Zhang, Dongping; Zhang, Zhengning; Feng, Zhiyong

    2014-01-01

    Ship detection in static UAV aerial images is a fundamental challenge in sea target detection and precise positioning. In this paper, an improved universal background model based on Grabcut algorithm is proposed to segment foreground objects from sea automatically. First, a sea template library including images in different natural conditions is built to provide an initial template to the model. Then the background trimap is obtained by combing some templates matching with region growing algorithm. The output trimap initializes Grabcut background instead of manual intervention and the process of segmentation without iteration. The effectiveness of our proposed model is demonstrated by extensive experiments on a certain area of real UAV aerial images by an airborne Canon 5D Mark. The proposed algorithm is not only adaptive but also with good segmentation. Furthermore, the model in this paper can be well applied in the automated processing of industrial images for related researches.

  9. BgCut: automatic ship detection from UAV images.

    PubMed

    Xu, Chao; Zhang, Dongping; Zhang, Zhengning; Feng, Zhiyong

    2014-01-01

    Ship detection in static UAV aerial images is a fundamental challenge in sea target detection and precise positioning. In this paper, an improved universal background model based on Grabcut algorithm is proposed to segment foreground objects from sea automatically. First, a sea template library including images in different natural conditions is built to provide an initial template to the model. Then the background trimap is obtained by combing some templates matching with region growing algorithm. The output trimap initializes Grabcut background instead of manual intervention and the process of segmentation without iteration. The effectiveness of our proposed model is demonstrated by extensive experiments on a certain area of real UAV aerial images by an airborne Canon 5D Mark. The proposed algorithm is not only adaptive but also with good segmentation. Furthermore, the model in this paper can be well applied in the automated processing of industrial images for related researches. PMID:24977182

  10. BgCut: Automatic Ship Detection from UAV Images

    PubMed Central

    Zhang, Zhengning; Feng, Zhiyong

    2014-01-01

    Ship detection in static UAV aerial images is a fundamental challenge in sea target detection and precise positioning. In this paper, an improved universal background model based on Grabcut algorithm is proposed to segment foreground objects from sea automatically. First, a sea template library including images in different natural conditions is built to provide an initial template to the model. Then the background trimap is obtained by combing some templates matching with region growing algorithm. The output trimap initializes Grabcut background instead of manual intervention and the process of segmentation without iteration. The effectiveness of our proposed model is demonstrated by extensive experiments on a certain area of real UAV aerial images by an airborne Canon 5D Mark. The proposed algorithm is not only adaptive but also with good segmentation. Furthermore, the model in this paper can be well applied in the automated processing of industrial images for related researches. PMID:24977182

  11. [In-flight absolute radiometric calibration of UAV multispectral sensor].

    PubMed

    Chen, Wei; Yan, Lei; Gou, Zhi-Yang; Zhao, Hong-Ying; Liu, Da-Ping; Duan, Yi-Ni

    2012-12-01

    Based on the data of the scientific experiment in Urad Front Banner for UAV Remote Sensing Load Calibration Field project, with the help of 6 hyperspectral radiometric targets with good Lambertian property, the wide-view multispectral camera in UAV was calibrated adopting reflectance-based method. The result reveals that for green, red and infrared channel, whose images were successfully captured, the linear correlation coefficients between the DN and radiance are all larger than 99%. In final analysis, the comprehensive error is no more than 6%. The calibration results demonstrate that the hyperspectral targets equipped by the calibration field are well suitable for air-borne multispectral load in-flight calibration. The calibration result is reliable and could be used in the retrieval of geophysical parameters.

  12. A sensor management framework for autonomous UAV surveillance

    NASA Astrophysics Data System (ADS)

    Ulvklo, Morgan; Nygards, Jonas; Karlholm, Jorgen; Skoglar, Per; Ahlberg, Jorgen; Nilsson, Jonas

    2005-05-01

    This paper presents components of a sensor management architecture for autonomous UAV systems equipped with IR and video sensors, focusing on two main areas. Firstly, a framework inspired by optimal control and information theory is presented for concurrent path and sensor planning. Secondly, a method for visual landmark selection and recognition is presented. The latter is intended to be used within a SLAM (Simultaneous Localization and Mapping) architecture for visual navigation. Results are presented on both simulated and real sensor data, the latter from the MASP system (Modular Airborne Sensor Platform), an in-house developed UAV surrogate system containing a gimballed IR camera, a video sensor, and an integrated high performance navigation system.

  13. Evaluation of a Metric Camera System Tailored for High Precision Uav Applications

    NASA Astrophysics Data System (ADS)

    Kraft, T.; Geßner, M.; Meißner, H.; Cramer, M.; Gerke, M.; Przybilla, H. J.

    2016-06-01

    In this paper we present the further evaluation of DLR's modular airborne camera system MACS-Micro for small unmanned aerial vehicle (UAV). The main focus is on standardized calibration procedures and on photogrammetric workflows. The current prototype consists of an industrial grade frame imaging camera with 12 megapixel resolutions and a compact GNSS/IMU solution which are operated by an embedded computing unit (CPU). The camera was calibrated once pre-flight and several times post-flight over a period of 5 month using a three dimensional test field. The verification of the radiometric quality of the acquired images has been done under controlled static conditions and kinematic conditions testing different demosaicing methods. The validation of MACS-Micro is done by comparing a traditional photogrammetric evaluation with the workflows of Agisoft Photoscan and Pix4D Mapper. The analyses are based on an aerial survey of an urban environment using precise ground control points and acquired GNSS observations. Aerial triangulations with different configuratrions of ground control points (GCP's) had been calculated, comparing the results of using a camera self-calibration and introducing fixed interior orientation parameters for Agisoft and Pix4D. The results are promising concerning the metric characteristics of the used camera and achieved accuracies in this test case. Further aspects have to be evaluated by further expanded test scenarios.

  14. Status of a UAV SAR Designed for Repeat Pass Interferometry for Deformation Measurements

    NASA Technical Reports Server (NTRS)

    Hensley, Scott; Wheeler, Kevin; Hoffman, Jim; Miller, Tim; Lou, Yunling; Muellerschoen, Ron; Zebker, Howard; Madsen, Soren; Rosen, Paul

    2004-01-01

    Under the NASA ESTO sponsored Instrument Incubator Program we have designed a lightweight, reconfigurable polarimetric L-band SAR designed for repeat pass deformation measurements of rapidly deforming surfaces of geophysical interest such as volcanoes or earthquakes. This radar will be installed on an unmanned airborne vehicle (UAV) or a lightweight, high-altitude, and long endurance platform such as the Proteus. After a study of suitable available platforms we selected the Proteus for initial development and testing of the system. We want to control the repeat track capability of the aircraft to be within a 10 m tube to support the repeat deformation capability. We conducted tests with the Proteus using real-time GPS with sub-meter accuracy to see if pilots could fly the aircraft within the desired tube. Our results show that pilots are unable to fly the aircraft with the desired accuracy and therefore an augmented autopilot will be required to meet these objectives. Based on the Proteus flying altitude of 13.7 km (45,000 ft), we are designing a fully polarimetric L-band radar with 80 MHz bandwidth and 16 km range swath. This radar will have an active electronic beam steering antenna to achieve Doppler centroid stability that is necessary for repeat-pass interferometry (RPI). This paper will present are design criteria, current design and expected science applications.

  15. Development of a bio-inspired UAV perching system

    NASA Astrophysics Data System (ADS)

    Xie, Pu

    Although technologies of unmanned aerial vehicles (UAVs) including micro air vehicles (MAVs) have been greatly advanced in the recent years, it is still very difficult for a UAV to perform some very challenging tasks such as perching to any desired spot reliably and agilely like a bird. Unlike the UAVs, the biological control mechanism of birds has been optimized through millions of year evolution and hence, they can perform many extremely maneuverability tasks, such as perching or grasping accurately and robustly. Therefore, we have good reason to learn from the nature in order to significantly improve the capabilities of UAVs. The development of a UAV perching system is becoming feasible, especially after a lot of research contributions in ornithology which involve the analysis of the bird's functionalities. Meanwhile, as technology advances in many engineering fields, such as airframes, propulsion, sensors, batteries, micro-electromechanical-system (MEMS), and UAV technology is also advancing rapidly. All of these research efforts in ornithology and the fast growing development technologies in UAV applications are motivating further interests and development in the area of UAV perching and grasping research. During the last decade, the research contributions about UAV perching and grasping were mainly based on fixed-wing, flapping-wing, and rotorcraft UAVs. However, most of the current researches in UAV systems with perching and grasping capability are focusing on either active (powered) grasping and perching or passive (unpowered) perching. Although birds do have both active and passive perching capabilities depending on their needs, there is no UAV perching system with both capabilities. In this project, we focused on filling this gap. Inspired by the anatomy analysis of bird legs and feet, a novel perching system has been developed to implement the bionics action for both active grasping and passive perching. In addition, for developing a robust and

  16. Hydrology with unmanned aerial vehicles (UAVs)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrologic remote sensing currently depends on expensive and infrequent aircraft observations for validation of operational satellite products, typically conducted during field campaigns that also include ground-based measurements. With the advent of new, hydrologically-relevant satellite missions, ...

  17. Accuracy assessment of topographic mapping using UAV image integrated with satellite images

    NASA Astrophysics Data System (ADS)

    Azmi, S. M.; Ahmad, Baharin; Ahmad, Anuar

    2014-02-01

    Unmanned Aerial Vehicle or UAV is extensively applied in various fields such as military applications, archaeology, agriculture and scientific research. This study focuses on topographic mapping and map updating. UAV is one of the alternative ways to ease the process of acquiring data with lower operating costs, low manufacturing and operational costs, plus it is easy to operate. Furthermore, UAV images will be integrated with QuickBird images that are used as base maps. The objective of this study is to make accuracy assessment and comparison between topographic mapping using UAV images integrated with aerial photograph and satellite image. The main purpose of using UAV image is as a replacement for cloud covered area which normally exists in aerial photograph and satellite image, and for updating topographic map. Meanwhile, spatial resolution, pixel size, scale, geometric accuracy and correction, image quality and information contents are important requirements needed for the generation of topographic map using these kinds of data. In this study, ground control points (GCPs) and check points (CPs) were established using real time kinematic Global Positioning System (RTK-GPS) technique. There are two types of analysis that are carried out in this study which are quantitative and qualitative assessments. Quantitative assessment is carried out by calculating root mean square error (RMSE). The outputs of this study include topographic map and orthophoto. From this study, the accuracy of UAV image is ± 0.460 m. As conclusion, UAV image has the potential to be used for updating of topographic maps.

  18. Visual navigation of the UAVs on the basis of 3D natural landmarks

    NASA Astrophysics Data System (ADS)

    Karpenko, Simon; Konovalenko, Ivan; Miller, Alexander; Miller, Boris; Nikolaev, Dmitry

    2015-12-01

    This work considers the tracking of the UAV (unmanned aviation vehicle) on the basis of onboard observations of natural landmarks including azimuth and elevation angles. It is assumed that UAV's cameras are able to capture the angular position of reference points and to measure the angles of the sight line. Such measurements involve the real position of UAV in implicit form, and therefore some of nonlinear filters such as Extended Kalman filter (EKF) or others must be used in order to implement these measurements for UAV control. Recently it was shown that modified pseudomeasurement method may be used to control UAV on the basis of the observation of reference points assigned along the UAV path in advance. However, the use of such set of points needs the cumbersome recognition procedure with the huge volume of on-board memory. The natural landmarks serving as such reference points which may be determined on-line can significantly reduce the on-board memory and the computational difficulties. The principal difference of this work is the usage of the 3D reference points coordinates which permits to determine the position of the UAV more precisely and thereby to guide along the path with higher accuracy which is extremely important for successful performance of the autonomous missions. The article suggests the new RANSAC for ISOMETRY algorithm and the use of recently developed estimation and control algorithms for tracking of given reference path under external perturbation and noised angular measurements.

  19. Autonomous target tracking of UAVs based on low-power neural network hardware

    NASA Astrophysics Data System (ADS)

    Yang, Wei; Jin, Zhanpeng; Thiem, Clare; Wysocki, Bryant; Shen, Dan; Chen, Genshe

    2014-05-01

    Detecting and identifying targets in unmanned aerial vehicle (UAV) images and videos have been challenging problems due to various types of image distortion. Moreover, the significantly high processing overhead of existing image/video processing techniques and the limited computing resources available on UAVs force most of the processing tasks to be performed by the ground control station (GCS) in an off-line manner. In order to achieve fast and autonomous target identification on UAVs, it is thus imperative to investigate novel processing paradigms that can fulfill the real-time processing requirements, while fitting the size, weight, and power (SWaP) constrained environment. In this paper, we present a new autonomous target identification approach on UAVs, leveraging the emerging neuromorphic hardware which is capable of massively parallel pattern recognition processing and demands only a limited level of power consumption. A proof-of-concept prototype was developed based on a micro-UAV platform (Parrot AR Drone) and the CogniMemTMneural network chip, for processing the video data acquired from a UAV camera on the y. The aim of this study was to demonstrate the feasibility and potential of incorporating emerging neuromorphic hardware into next-generation UAVs and their superior performance and power advantages towards the real-time, autonomous target tracking.

  20. The Processing of Image Data Collected by Light UAV Systems for GIS Data Capture and Updating

    NASA Astrophysics Data System (ADS)

    Yastikli, N.; Bagci, I.; Beser, C.

    2013-10-01

    The collection and updating of 3D data is the one of the important steps for GIS applications which require fast and efficient data collection methods. The photogrammetry has been used for many years as a data collection method for GIS application in larger areas. The Unmanned Aerial Vehicles (UAV) Systems gained increasing attraction in geosciences for cost effective data capture and updating at high spatial and temporal resolution during the last years. These autonomously flying UAV systems are usually equipped with different sensors such as GPS receiver, microcomputers, gyroscopes and miniaturized sensor systems for navigation, positioning, and mapping purposes. The UAV systems can be used for data collection for digital elevation model DEM and orthoimages generation in GIS application at small areas. In this study, data collection and processing by light UAV system will be evaluated for GIS data capture and updating for small areas where not feasible for traditional photogrammetry. The main aim of this study is to design the low cost light UAV system for GIS data capture and update. The investigation was based on the aerial images which recorded during the flights performed with UAV system over the test site in Davutpasa Campus of Yildiz Technical University, Istanbul. The quality of generated DEM and ortho-images from UAV flights was discussed for GIS data capture and updating for small areas.

  1. A novel method of EMC test at the system level of UAV

    NASA Astrophysics Data System (ADS)

    Li, Bo; Huang, Daqing; Nie, Riurui

    2006-11-01

    The purport of EMC (Electromagnetic Compatibility) is that the electric and electronic equipments or subsystems can work normally according to the advanced project requirements in the intentional electromagnetic environments. Nowadays, design for EMC has played a more and more important role in system plan. The UAV (Unmanned Aerial Vehicle) devisers have cognizance of this point too. But it is regretful that the importance of EMC test is often ignored in the design of UAV, especially the test at the system level, to the detriment of total UAV performance. Complete EMC test at the systems level is often a difficult goal, since system is often too large to adequately or efficiently test, or complete UAV is not for test available until initial customer installation, where test could be impractical. And it is more serious that there are no ready-made UAV standards of EMC test at the system level to be complied with. Following a review of definition and background of systems EMC of UAV, along with the relationships between the EMC test at the subsystem level and the test at the system level, the author describes an novel and effective method of EMC test at the system level, continues with the details of the testing items and their academic bases and some noticeable proceedings of the test. Finally, some conclusions of the EMC test at the system level of UAV are given.

  2. 3D Tree Dimensionality Assessment Using Photogrammetry and Small Unmanned Aerial Vehicles.

    PubMed

    Gatziolis, Demetrios; Lienard, Jean F; Vogs, Andre; Strigul, Nikolay S

    2015-01-01

    Detailed, precise, three-dimensional (3D) representations of individual trees are a prerequisite for an accurate assessment of tree competition, growth, and morphological plasticity. Until recently, our ability to measure the dimensionality, spatial arrangement, shape of trees, and shape of tree components with precision has been constrained by technological and logistical limitations and cost. Traditional methods of forest biometrics provide only partial measurements and are labor intensive. Active remote technologies such as LiDAR operated from airborne platforms provide only partial crown reconstructions. The use of terrestrial LiDAR is laborious, has portability limitations and high cost. In this work we capitalized on recent improvements in the capabilities and availability of small unmanned aerial vehicles (UAVs), light and inexpensive cameras, and developed an affordable method for obtaining precise and comprehensive 3D models of trees and small groups of trees. The method employs slow-moving UAVs that acquire images along predefined trajectories near and around targeted trees, and computer vision-based approaches that process the images to obtain detailed tree reconstructions. After we confirmed the potential of the methodology via simulation we evaluated several UAV platforms, strategies for image acquisition, and image processing algorithms. We present an original, step-by-step workflow which utilizes open source programs and original software. We anticipate that future development and applications of our method will improve our understanding of forest self-organization emerging from the competition among trees, and will lead to a refined generation of individual-tree-based forest models.

  3. Launch of a Vehicle from a Ramp

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2011-10-01

    Avehicle proceeding up an inclined ramp will become airborne if the ramp comes to a sudden end and if the vehicle fails to stop before it reaches the end of the ramp. A vehicle may also become airborne if it passes over the top of a hill at sufficient speed. In both cases, the vehicle becomes airborne if the point of support underneath the vehicle falls below the trajectory that would be followed by the vehicle in the presence of gravity alone. When the vehicle becomes airborne, the normal reaction force exerted by the ramp or the hill drops to zero, first on the front wheels and then on the rear wheels. Just prior to the vehicle's becoming airborne, the normal reaction force on the rear wheels acts to exert a torque on the vehicle, causing the vehicle to rotate. After the rear wheels become airborne, the vehicle will continue to rotate until it lands some distance from the launch point.

  4. Roadside IED detection using subsurface imaging radar and rotary UAV

    NASA Astrophysics Data System (ADS)

    Qin, Yexian; Twumasi, Jones O.; Le, Viet Q.; Ren, Yu-Jiun; Lai, C. P.; Yu, Tzuyang

    2016-05-01

    Modern improvised explosive device (IED) and mine detection sensors using microwave technology are based on ground penetrating radar operated by a ground vehicle. Vehicle size, road conditions, and obstacles along the troop marching direction limit operation of such sensors. This paper presents a new conceptual design using a rotary unmanned aerial vehicle (UAV) to carry subsurface imaging radar for roadside IED detection. We have built a UAV flight simulator with the subsurface imaging radar running in a laboratory environment and tested it with non-metallic and metallic IED-like targets. From the initial lab results, we can detect the IED-like target 10-cm below road surface while carried by a UAV platform. One of the challenges is to design the radar and antenna system for a very small payload (less than 3 lb). The motion compensation algorithm is also critical to the imaging quality. In this paper, we also demonstrated the algorithm simulation and experimental imaging results with different IED target materials, sizes, and clutters.

  5. Uav for Geodata Acquisition in Agricultureal and Forestal Applications

    NASA Astrophysics Data System (ADS)

    Reidelstürz, P.; Schrenk, L.; Littmann, W.

    2011-09-01

    In the field of precision-farming research, solutions are worked out to combine ecological and economical requirements in a harmonic way. Integrating hightech in agricultural machinery, natural differences in the fields (biodiversity) can be detected and considered to economize agricultural resources and to give respect to natural ecological variability at the same time. Using precision farming resources, machining - and labour time can be economized, productivness can be improved, environmental burden can be discharged and documentation of production processes can be improved. To realize precision farming it is essential to make contemporary large scale data of the biodiversity in the field available. In the last years effectual traktor based equipment for real time precision farming applications was developed. Using remote sensing, biomass diversity of the field can be considered while applicating operating ressources economicly. Because these large scale data aquisition depends on expensive tractor based inspections, capable Unmanned Aerial Vehicles (UAVs) could complement or in special situations even replace such tractor based data aquisition needed for the realization of precision farming strategies. The specific advantages and application slots of UAVs seems to be ideal for the usage in the field of precision farming. For example the size of even large agricultural fields in germany can be managed even by smaller UAVs. Data can be captured spontaneously, promptly, in large scale, with less respect of weather conditions. In agricultural regions UAV flights can be arranged in visual range as actually the legislator requires in germany, especially because the use of autopilotsystems in fact is nessecary to assure regular area-wide data without gaps but not to fly in non-visible regions. Also a minimized risk of hazard is given, flying UAVs over deserted agricultural areas. In a first stage CIS GmbH cooperated with "Institute For Flightsystems" of the University

  6. Wavelength-adaptive dehazing using histogram merging-based classification for UAV images.

    PubMed

    Yoon, Inhye; Jeong, Seokhwa; Jeong, Jaeheon; Seo, Doochun; Paik, Joonki

    2015-03-19

    Since incoming light to an unmanned aerial vehicle (UAV) platform can be scattered by haze and dust in the atmosphere, the acquired image loses the original color and brightness of the subject. Enhancement of hazy images is an important task in improving the visibility of various UAV images. This paper presents a spatially-adaptive dehazing algorithm that merges color histograms with consideration of the wavelength-dependent atmospheric turbidity. Based on the wavelength-adaptive hazy image acquisition model, the proposed dehazing algorithm consists of three steps: (i) image segmentation based on geometric classes; (ii) generation of the context-adaptive transmission map; and (iii) intensity transformation for enhancing a hazy UAV image. The major contribution of the research is a novel hazy UAV image degradation model by considering the wavelength of light sources. In addition, the proposed transmission map provides a theoretical basis to differentiate visually important regions from others based on the turbidity and merged classification results.

  7. Optimization of a Turboprop UAV for Maximum Loiter and Specific Power Using Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Dinc, Ali

    2016-09-01

    In this study, a genuine code was developed for optimization of selected parameters of a turboprop engine for an unmanned aerial vehicle (UAV) by employing elitist genetic algorithm. First, preliminary sizing of a UAV and its turboprop engine was done, by the code in a given mission profile. Secondly, single and multi-objective optimization were done for selected engine parameters to maximize loiter duration of UAV or specific power of engine or both. In single objective optimization, as first case, UAV loiter time was improved with an increase of 17.5% from baseline in given boundaries or constraints of compressor pressure ratio and burner exit temperature. In second case, specific power was enhanced by 12.3% from baseline. In multi-objective optimization case, where previous two objectives are considered together, loiter time and specific power were increased by 14.2% and 9.7% from baseline respectively, for the same constraints.

  8. Compact hyperspectral camera in the mid-infrared for small UAVs

    NASA Astrophysics Data System (ADS)

    Pola Fossi, Armande; Ferrec, Yann; Coudrain, Christophe; Roux, Nicolas; Kling, Emmanuel; Guérineau, Nicolas

    2016-05-01

    Hyperspectral imaging from small unmanned aerial vehicles (UAVs) arouses a growing interest, as well for military applications as for civilian applications like agriculture management, pollution monitoring or mining. This paper establishes a quick state of the art of cameras of which the capabilities in small-UAVs embedded campaigns have been demonstrated. We also introduce a novel compact hyperspectral camera operating in mid-infrared spectral range embeddable on small UAVs. This camera combines birefringent interferometer for size reduction and cooled imaging optics for a better signal noise ratio. The design of a first prototype and first results from a ground-based measurement campaign, of which the goal was an optical concept validation, is also discussed. Finally, we present the design modifications for the small-UAVs-embeddable version.

  9. It's about time; Repeated field sampling and flexible UAV platforms for a changing globe

    NASA Astrophysics Data System (ADS)

    Crutsinger, G.

    2015-12-01

    Unmanned Aerial Vehicles (UAVs) are quickly being adopted across the field sciences and will revolutionizing the speed and spatial scale of data collection. As a result, UAVs will alleviate much of the burden placed on boots-on-the-ground researchers as they seek to address fundamental scientific questionsa ssociated with global change. Concurrently, UAVs will initiate a rapid rise in time-series data, whether from monitoring weather patterns, measuring shifts in phenology due to a warming temperatures, or tracking range expansion and contraction of species. The challenges within the scientific community will be in the standardization of data collection, protocol sharing, and data management. The emergence of flexible aerial platforms within the commercial UAV space with multiple sensor configurations, open software application development, and cloud-based services should do much to address these challenges, but only if there is close collaboration between the industry and academic research partners.

  10. Wavelength-Adaptive Dehazing Using Histogram Merging-Based Classification for UAV Images

    PubMed Central

    Yoon, Inhye; Jeong, Seokhwa; Jeong, Jaeheon; Seo, Doochun; Paik, Joonki

    2015-01-01

    Since incoming light to an unmanned aerial vehicle (UAV) platform can be scattered by haze and dust in the atmosphere, the acquired image loses the original color and brightness of the subject. Enhancement of hazy images is an important task in improving the visibility of various UAV images. This paper presents a spatially-adaptive dehazing algorithm that merges color histograms with consideration of the wavelength-dependent atmospheric turbidity. Based on the wavelength-adaptive hazy image acquisition model, the proposed dehazing algorithm consists of three steps: (i) image segmentation based on geometric classes; (ii) generation of the context-adaptive transmission map; and (iii) intensity transformation for enhancing a hazy UAV image. The major contribution of the research is a novel hazy UAV image degradation model by considering the wavelength of light sources. In addition, the proposed transmission map provides a theoretical basis to differentiate visually important regions from others based on the turbidity and merged classification results. PMID:25808767

  11. Wavelength-adaptive dehazing using histogram merging-based classification for UAV images.

    PubMed

    Yoon, Inhye; Jeong, Seokhwa; Jeong, Jaeheon; Seo, Doochun; Paik, Joonki

    2015-01-01

    Since incoming light to an unmanned aerial vehicle (UAV) platform can be scattered by haze and dust in the atmosphere, the acquired image loses the original color and brightness of the subject. Enhancement of hazy images is an important task in improving the visibility of various UAV images. This paper presents a spatially-adaptive dehazing algorithm that merges color histograms with consideration of the wavelength-dependent atmospheric turbidity. Based on the wavelength-adaptive hazy image acquisition model, the proposed dehazing algorithm consists of three steps: (i) image segmentation based on geometric classes; (ii) generation of the context-adaptive transmission map; and (iii) intensity transformation for enhancing a hazy UAV image. The major contribution of the research is a novel hazy UAV image degradation model by considering the wavelength of light sources. In addition, the proposed transmission map provides a theoretical basis to differentiate visually important regions from others based on the turbidity and merged classification results. PMID:25808767

  12. Cooperative control of UAVs for localization of intermittently emitting mobile targets.

    PubMed

    Pack, Daniel J; Delima, Pedro; Toussaint, Gregory J; York, George

    2009-08-01

    Compared with a single platform, cooperative autonomous unmanned aerial vehicles (UAVs) offer efficiency and robustness in performing complex tasks. Focusing on ground mobile targets that intermittently emit radio frequency signals, this paper presents a decentralized control architecture for multiple UAVs, equipped only with rudimentary sensors, to search, detect, and locate targets over large areas. The proposed architecture has in its core a decision logic which governs the state of operation for each UAV based on sensor readings and communicated data. To support the findings, extensive simulation results are presented, focusing primarily on two success measures that the UAVs seek to minimize: overall time to search for a group of targets and the final target localization error achieved. The results of the simulations have provided support for hardware flight tests. PMID:19473935

  13. Autonomous UAV persistent surveillance using bio-inspired strategies

    NASA Astrophysics Data System (ADS)

    Burman, Jerry; Hespanha, Joao; Madhow, Upamanyu; Isaacs, Jason; Venkateswaran, Sriram; Pham, Tien

    2012-06-01

    A team consisting of Teledyne Scientific Company, the University of California at Santa Barbara, the Army Research Laboratory, the Engineer Research and Development Center, and IBM UK is developing technologies in support of automated data exfiltration from heterogeneous battlefield sensor networks to enhance situational awareness for dismounts and command echelons. Unmanned aerial vehicles (UAV) provide an effective means to autonomously collect data from a sparse network of unattended ground sensors (UGSs) that cannot communicate with each other. UAVs are used to reduce the system reaction time by generating autonomous collection routes that are data-driven. Bioinspired techniques for autonomous search provide a novel strategy to detect, capture and fuse data from heterogeneous sensor networks. The bio-inspired algorithm is based on chemotaxis or the motion of bacteria seeking nutrients in their environment. Field tests of a bio-inspired system that routed UAVs were conducted in June 2011 at Camp Roberts, CA. The field test results showed that such a system can autonomously detect and locate the source of terrestrial events with very high accuracy and visually verify the event. In June 2011, field tests of the system were completed and include the use of multiple autonomously controlled UAVs, detection and disambiguation of multiple acoustic events occurring in short time frames, optimal sensor placement based on local phenomenology and the use of the International Technology Alliance (ITA) Sensor Network Fabric. The system demonstrated TRL 6 performance in the field at Camp Roberts.

  14. The future of structural fieldwork - UAV assisted aerial photogrammetry

    NASA Astrophysics Data System (ADS)

    Vollgger, Stefan; Cruden, Alexander

    2015-04-01

    Unmanned aerial vehicles (UAVs), commonly referred to as drones, are opening new and low cost possibilities to acquire high-resolution aerial images and digital surface models (DSM) for applications in structural geology. UAVs can be programmed to fly autonomously along a user defined grid to systematically capture high-resolution photographs, even in difficult to access areas. The photographs are subsequently processed using software that employ SIFT (scale invariant feature transform) and SFM (structure from motion) algorithms. These photogrammetric routines allow the extraction of spatial information (3D point clouds, digital elevation models, 3D meshes, orthophotos) from 2D images. Depending on flight altitude and camera setup, sub-centimeter spatial resolutions can be achieved. By "digitally mapping" georeferenced 3D models and images, orientation data can be extracted directly and used to analyse the structural framework of the mapped object or area. We present UAV assisted aerial mapping results from a coastal platform near Cape Liptrap (Victoria, Australia), where deformed metasediments of the Palaeozoic Lachlan Fold Belt are exposed. We also show how orientation and spatial information of brittle and ductile structures extracted from the photogrammetric model can be linked to the progressive development of folds and faults in the region. Even though there are both technical and legislative limitations, which might prohibit the use of UAVs without prior commercial licensing and training, the benefits that arise from the resulting high-resolution, photorealistic models can substantially contribute to the collection of new data and insights for applications in structural geology.

  15. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation.

    PubMed

    Nitti, Davide O; Bovenga, Fabio; Chiaradia, Maria T; Greco, Mario; Pinelli, Gianpaolo

    2015-07-28

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system.

  16. UAV Monitoring for Enviromental Management in Galapagos Islands

    NASA Astrophysics Data System (ADS)

    Ballari, D.; Orellana, D.; Acosta, E.; Espinoza, A.; Morocho, V.

    2016-06-01

    In the Galapagos Islands, where 97% of the territory is protected and ecosystem dynamics are highly vulnerable, timely and accurate information is key for decision making. An appropriate monitoring system must meet two key features: on one hand, being able to capture information in a systematic and regular basis, and on the other hand, to quickly gather information on demand for specific purposes. The lack of such a system for geographic information limits the ability of Galapagos Islands' institutions to evaluate and act upon environmental threats such as invasive species spread and vegetation degradation. In this context, the use of UAVs (unmanned aerial vehicles) for capturing georeferenced images is a promising technology for environmental monitoring and management. This paper explores the potential of UAV images for monitoring degradation of littoral vegetation in Puerto Villamil (Isabela Island, Galapagos, Ecuador). Imagery was captured using two camera types: Red Green Blue (RGB) and Infrarred Red Green (NIR). First, vegetation presence was identified through NDVI. Second, object-based classification was carried out for characterization of vegetation vigor. Results demonstrates the feasibility of UAV technology for base-line studies and monitoring on the amount and vigorousness of littoral vegetation in the Galapagos Islands. It is also showed that UAV images are not only useful for visual interpretation and object delineation, but also to timely produce useful thematic information for environmental management.

  17. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation

    PubMed Central

    Nitti, Davide O.; Bovenga, Fabio; Chiaradia, Maria T.; Greco, Mario; Pinelli, Gianpaolo

    2015-01-01

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimate UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system. PMID:26225977

  18. An automated 3D reconstruction method of UAV images

    NASA Astrophysics Data System (ADS)

    Liu, Jun; Wang, He; Liu, Xiaoyang; Li, Feng; Sun, Guangtong; Song, Ping

    2015-10-01

    In this paper a novel fully automated 3D reconstruction approach based on low-altitude unmanned aerial vehicle system (UAVs) images will be presented, which does not require previous camera calibration or any other external prior knowledge. Dense 3D point clouds are generated by integrating orderly feature extraction, image matching, structure from motion (SfM) and multi-view stereo (MVS) algorithms, overcoming many of the cost, time limitations of rigorous photogrammetry techniques. An image topology analysis strategy is introduced to speed up large scene reconstruction by taking advantage of the flight-control data acquired by UAV. Image topology map can significantly reduce the running time of feature matching by limiting the combination of images. A high-resolution digital surface model of the study area is produced base on UAV point clouds by constructing the triangular irregular network. Experimental results show that the proposed approach is robust and feasible for automatic 3D reconstruction of low-altitude UAV images, and has great potential for the acquisition of spatial information at large scales mapping, especially suitable for rapid response and precise modelling in disaster emergency.

  19. Mapping Snowfields in the High Arctic by UAV

    NASA Astrophysics Data System (ADS)

    Klump, Jens; Leya, Thomas; Fuhr, Günter

    2014-05-01

    Plant habitats are often influenced by small scale factors of substrate composition, topography and water sources that influence the availability of water and nutrients. In our lomg-term study to investigate the the distribution and dispersal strategies as well as the life cycle of psychrophilic algae (snow algae) it was necessary to get a better understanding of the structure of the snowfields where these algae live. Previous attempts to map snowfields using tethered platforms, such as kites or balloons, had proven to be difficult due to the very unstable weather conditions in the extreme environment of the High Arctic. The inherent problems of tethered platforms could be overcome with unmanned aerial vehicles (UAV). During the August 2013 field campaign on the Svalbard archipelago we used an Asctec Falcon 8 UAV to map snowfields and glacier surfaces in the visible and thermal infra-red spectrum. The georeferenced images were assembled into photo mosaic maps which were also converted into digital elevation models. The photo mosaic maps and digital elevation models gave new insights into small-scale factors that influence the physical and chemical conditions of the snow algae habitat. This presentation gives an overview of our results from the use of UAV for the mapping of snowfields in the High Arctic and discusses the risks and limitations of UAV in this extreme environment.

  20. a Light-Weight Laser Scanner for Uav Applications

    NASA Astrophysics Data System (ADS)

    Tommaselli, A. M. G.; Torres, F. M.

    2016-06-01

    Unmanned Aerial Vehicles (UAV) have been recognized as a tool for geospatial data acquisition due to their flexibility and favourable cost benefit ratio. The practical use of laser scanning devices on-board UAVs is also developing with new experimental and commercial systems. This paper describes a light-weight laser scanning system composed of an IbeoLux scanner, an Inertial Navigation System Span-IGM-S1, from Novatel, a Raspberry PI portable computer, which records data from both systems and an octopter UAV. The performance of this light-weight system was assessed both for accuracy and with respect to point density, using Ground Control Points (GCP) as reference. Two flights were performed with the UAV octopter carrying the equipment. In the first trial, the flight height was 100 m with six strips over a parking area. The second trial was carried out over an urban park with some buildings and artificial targets serving as reference Ground Control Points. In this experiment a flight height of 70 m was chosen to improve target response. Accuracy was assessed based on control points the coordinates of which were measured in the field. Results showed that vertical accuracy with this prototype is around 30 cm, which is acceptable for forest applications but this accuracy can be improved using further refinements in direct georeferencing and in the system calibration.

  1. Marine object detection in UAV full-motion video

    NASA Astrophysics Data System (ADS)

    Parameswaran, Shibin; Lane, Corey; Bagnall, Bryan; Buck, Heidi

    2014-06-01

    Recent years have seen an increased use of Unmanned Aerial Vehicles (UAV) with video-recording capability for Maritime Domain Awareness (MDA) and other surveillance operations. In order for these e orts to be effective, there is a need to develop automated algorithms to process the full-motion videos (FMV) captured by UAVs in an efficient and timely manner to extract meaningful information that can assist human analysts and decision makers. This paper presents a generalizeable marine object detection system that is specifically designed to process raw video footage streaming from UAVs in real-time. Our approach does not make any assumptions about the object and/or background characteristics because, in the MDA domain, we encounter varying background and foreground characteristics such as boats, bouys and ships of varying sizes and shapes, wakes, white caps on water, glint from the sun, to name but a few. Our efforts rely on basic signal processing and machine learning approaches to develop a generic object detection system that maintains a high level of performance without making prior assumptions about foreground-background characteristics and does not experience abrupt performance degradation when subjected to variations in lighting, background characteristics, video quality, abrupt changes in video perspective, size, appearance and number of the targets. In the following report, in addition to our marine object detection system, we present representative object detection results on some real-world UAV full-motion video data.

  2. Hierarchical scheduling method of UAV resources for emergency surveying

    NASA Astrophysics Data System (ADS)

    Zhang, Junxiao; Zhu, Qing; Shen, Fuqiang; Miao, Shuangxi; Cao, Zhenyu; Weng, Qiqiang

    2015-12-01

    Traditional mission scheduling methods are unable to meet the timeliness requirements of emergency surveying. Different size and overlaps of different missions lead to inefficient scheduling and poor mission returns. Especially for UAVs, based on their agile and flexible ability, the scheduling result becomes diversiform; as affected by environment and unmanned aerial vehicle performance, different scheduling will lead to different time costs and mission payoffs. An effective scheduling solution is to arrange the UAVs reasonably to complete as many as missions possible with better quality and satisfaction of different demands. This paper proposes a method for mission decomposition or aggregation to generate a mission unit for specific UAVs based on the spatio-temporal constraints of different missions and UAV observation ability demands. In this way, the problems of lack or redundancy of resource scheduling, which can be caused by mission overload, various information demands and spatial overlapping will be effectively reduced. Furthermore, the global efficiency evaluation function is built by considering typical scheduling objectives, such as mission returns, priority and load balancing of resources. Then, an improved ant colony algorithm is designed to acquire an optimal scheduling scheme and the dynamic adjustment strategy is employed. Finally, the correctness and validity are demonstrated by the simulation experiment.

  3. Enhancements in Uav Flight Control and Sensor Orientation

    NASA Astrophysics Data System (ADS)

    Bäumker, M.; Przybilla, H.-J.; Zurhorst, A.

    2013-08-01

    The acquisition of photogrammetric image data by means of Unmanned Aerial Vehicles (UAV) has developed in recent years to an interesting new measurement method especially for small to medium sizes of objects. In addition the latest developments in the field of navigation systems (GNSS), of inertial sensors and other sensors in combination with powerful and easy to program microcontrollers have made a major contribution to this. In particular, the development of MEMS sensors has triggered the boom of the UAV and has given decisively influence and it is still going on. The integration of sensors on a single board not only enables a cost-effective manufacturing and mass production, but also the use in accordance with small, lightweight UAV. The latest developments on a 50 mm × 50 mm-sized circuit board combine the sensors and the microcontroller for the flight control and flight navigation. Both the board and the microcontroller are easy to program and maintain several interfaces for connecting additional sensors, such as GNSS, ultrasonic sensors and telemetry. This article presents the UAV system of the Bochum University of Applied Sciences, the used sensors and the obtained results for accurate georeferencing.

  4. Feasibility of Using Synthetic Aperture Radar to Aid UAV Navigation.

    PubMed

    Nitti, Davide O; Bovenga, Fabio; Chiaradia, Maria T; Greco, Mario; Pinelli, Gianpaolo

    2015-01-01

    This study explores the potential of Synthetic Aperture Radar (SAR) to aid Unmanned Aerial Vehicle (UAV) navigation when Inertial Navigation System (INS) measurements are not accurate enough to eliminate drifts from a planned trajectory. This problem can affect medium-altitude long-endurance (MALE) UAV class, which permits heavy and wide payloads (as required by SAR) and flights for thousands of kilometres accumulating large drifts. The basic idea is to infer position and attitude of an aerial platform by inspecting both amplitude and phase of SAR images acquired onboard. For the amplitude-based approach, the system navigation corrections are obtained by matching the actual coordinates of ground landmarks with those automatically extracted from the SAR image. When the use of SAR amplitude is unfeasible, the phase content can be exploited through SAR interferometry by using a reference Digital Terrain Model (DTM). A feasibility analysis was carried out to derive system requirements by exploring both radiometric and geometric parameters of the acquisition setting. We showed that MALE UAV, specific commercial navigation sensors and SAR systems, typical landmark position accuracy and classes, and available DTMs lead to estimated UAV coordinates with errors bounded within ±12 m, thus making feasible the proposed SAR-based backup system. PMID:26225977

  5. Geometric calibration and accuracy assessment of a multispectral imager on UAVs

    NASA Astrophysics Data System (ADS)

    Zheng, Fengjie; Yu, Tao; Chen, Xingfeng; Chen, Jiping; Yuan, Guoti

    2012-11-01

    The increasing developments in Unmanned Aerial Vehicles (UAVs) platforms and associated sensing technologies have widely promoted UAVs remote sensing application. UAVs, especially low-cost UAVs, limit the sensor payload in weight and dimension. Mostly, cameras on UAVs are panoramic, fisheye lens, small-format CCD planar array camera, unknown intrinsic parameters and lens optical distortion will cause serious image aberrations, even leading a few meters or tens of meters errors in ground per pixel. However, the characteristic of high spatial resolution make accurate geolocation more critical to UAV quantitative remote sensing research. A method for MCC4-12F Multispectral Imager designed to load on UAVs has been developed and implemented. Using multi-image space resection algorithm to assess geometric calibration parameters of random position and different photogrammetric altitudes in 3D test field, which is suitable for multispectral cameras. Both theoretical and practical accuracy assessments were selected. The results of theoretical strategy, resolving object space and image point coordinate differences by space intersection, showed that object space RMSE were 0.2 and 0.14 pixels in X direction and in Y direction, image space RMSE were superior to 0.5 pixels. In order to verify the accuracy and reliability of the calibration parameters,practical study was carried out in Tianjin UAV flight experiments, the corrected accuracy validated by ground checkpoints was less than 0.3m. Typical surface reflectance retrieved on the basis of geo-rectified data was compared with ground ASD measurement resulting 4% discrepancy. Hence, the approach presented here was suitable for UAV multispectral imager.

  6. Multi-temporal UAV-borne LiDAR point clouds for vegetation analysis - a case study

    NASA Astrophysics Data System (ADS)

    Mandlburger, Gottfried; Wieser, Martin; Hollaus, Markus; Pfennigbauer, Martin; Riegl, Ursula

    2016-04-01

    In the recent past the introduction of compact and lightweight LiDAR (Light Detection And Ranging) sensors together with progress in UAV (Unmanned Aerial Vehicle) technology allowed the integration of laser scanners on remotely piloted multicopter, helicopter-type and even fixed-wing platforms. The multi-target capabilities of state-of-the-art time-of-flight full-waveform laser sensors operated from low flying UAV-platforms has enabled capturing of the entire 3D structure of semi-transparent objects like deciduous forests under leaf-off conditions in unprecedented density and completeness. For such environments it has already been demonstrated that UAV-borne laser scanning combines the advantages of terrestrial laser scanning (high point density, short range) and airborne laser scanning (bird's eye perspective, homogeneous point distribution). Especially the oblique looking capabilities of scanners with a large field of view (>180°) enable capturing of vegetation from different sides resulting in a constantly high point density also in the sub canopy domain. Whereas the findings stated above were drawn based on a case study carried out in February 2015 with the Riegl VUX-1UAV laser scanner system mounted on a Riegl RiCopter octocopter UAV-platform over an alluvial forest at the Pielach River (Lower Austria), the site was captured a second time with the same sensor system and mission parameters at the end of the vegetation period on October 28th, 2015. The main goal of this experiment was to assess the impact of the late autumn foliage on the achievable 3D point density. Especially the entire understory vegetation and certain tree species (e.g. willow) were still in full leaf whereas the bigger trees (poplar) where already partly defoliated. The comparison revealed that, although both campaigns featured virtually the same laser shot count, the ground point density dropped from 517 points/m2 in February (leaf-off) to 267 points/m2 end of October (leaf-on). The

  7. Comprehensive UAV agricultural remote-sensing research at Texas A M University

    NASA Astrophysics Data System (ADS)

    Thomasson, J. Alex; Shi, Yeyin; Olsenholler, Jeffrey; Valasek, John; Murray, Seth C.; Bishop, Michael P.

    2016-05-01

    Unmanned aerial vehicles (UAVs) have advantages over manned vehicles for agricultural remote sensing. Flying UAVs is less expensive, is more flexible in scheduling, enables lower altitudes, uses lower speeds, and provides better spatial resolution for imaging. The main disadvantage is that, at lower altitudes and speeds, only small areas can be imaged. However, on large farms with contiguous fields, high-quality images can be collected regularly by using UAVs with appropriate sensing technologies that enable high-quality image mosaics to be created with sufficient metadata and ground-control points. In the United States, rules governing the use of aircraft are promulgated and enforced by the Federal Aviation Administration (FAA), and rules governing UAVs are currently in flux. Operators must apply for appropriate permissions to fly UAVs. In the summer of 2015 Texas A&M University's agricultural research agency, Texas A&M AgriLife Research, embarked on a comprehensive program of remote sensing with UAVs at its 568-ha Brazos Bottom Research Farm. This farm is made up of numerous fields where various crops are grown in plots or complete fields. The crops include cotton, corn, sorghum, and wheat. After gaining FAA permission to fly at the farm, the research team used multiple fixed-wing and rotary-wing UAVs along with various sensors to collect images over all parts of the farm at least once per week. This article reports on details of flight operations and sensing and analysis protocols, and it includes some lessons learned in the process of developing a UAV remote-sensing effort of this sort.

  8. Applications for mini VTOL UAV for law enforcement

    NASA Astrophysics Data System (ADS)

    Murphy, Douglas W.; Cycon, James

    1999-01-01

    Remotely operated vehicle systems, ground and air, have great potential for supporting law enforcement operations. These systems with their onboard sensors, can assist in collecting evidence, performing long-term surveillance or in assessing hazardous situations prior to committing personnel. Remote ground vehicles are presently used by many police departments for ordnance clearing missions. Unmanned ground vehicles (UGVs) typically offer long endurance, and are intuitive to operate, but can be severely limited in where they can go by terrain and obstacles. Unmanned air vehicles (UAVs) have 3-D mobility, but have landing and takeoff restrictions, mission time limitations, and typically are demanding to operate. A new capability has been demonstrated for the U.S. military that shows great promise for aiding police agencies. This concept uses a shrouded rotor, vertical take off and landing (VTOL), an unmanned air vehicle to provide mobility to sensors and other payloads. This system can either perform surveillance from the air or travel to a remote location and land to position onboard sensors to perform long-term surveillance from the ground. This mobility platform concept can also be used to position packages (e.g., communications repeaters) or deliver and deploy non-lethal agents. This paper presents the concept of a small, UAV, VTOL, sensor mobility system for support of law enforcement operations. It then discusses operational feasibility and briefly reviews demonstrations of surveillance and sensor placement operations in military urban terrain scenarios performed by the Space and Naval Warfare (SPAWAR) Systems Center San Diego (SSCSD) and Sikorsky Aircraft with their full-size Cypher UAV. We then discuss the practicality of reducing the size of this capability to a system small enough to be transported in standard police vehicles and which can be easily operated by law enforcement personnel.

  9. A system-of-systems perspective for simultaneous UAV sizing and allocation using design of experiments and simulation

    NASA Astrophysics Data System (ADS)

    Bociaga, Michael L.

    Traditional approaches to aircraft sizing focus on maximizing the performance of the individual airframe as a standalone system. Customers, such as the Department of Defense, have recently looked more towards all-encompassing solutions to large problems by using a System-of-Systems approach instead of maximizing capability from a single aircraft or similar monolithic system. Shrinking budgets call for making the most efficient use of existing assets and addressing capability gaps in broad frameworks. The result is that optimizing the aircraft alone may not provide the customer with needed capabilities. Unmanned Aerial Vehicles (UAVs) performing Intelligence, Surveillance, and Reconnaissance (ISR) missions provide an example of systems designed to operate with other independent systems as part of a system-of-systems. In this research, a fleet of UAVs will provide wildfire detection in high terrain. The research investigates how to allocate existing systems along with a number of yet-to-be-defined UAVs. In this manner, the new UAVs may not be optimal for individual aircraft-based performance metrics, but they will enhance the capabilities of the fleet. Such a large, complex problem requires decomposition into a resource allocation problem using a Design of Experiments (DoE) to select configurations of UAV fleets to test by simulation using STK's Aircraft Mission Modeler software package at the System-of-Systems level, and an aircraft sizing sub-problem using an SQP algorithm and the Breguet endurance equation to size the new UAV. The STK output is modeled using main effects and a response surface that shows the tradeoff between cost and coverage, enabling the customer to select the optimal allocation of existing and new UAVs and determine the key characteristics of the new UAVs that fit into this fleet. The new UAV sized for this specific mission, but from a System-of-Systems perspective, complements the UAV fleet, enhancing the capabilities of the System

  10. New distributed radar technology based on UAV or UGV application

    NASA Astrophysics Data System (ADS)

    Molchanov, Pavlo A.; Contarino, Vincent M.

    2013-05-01

    Regular micro and nano radars cannot provide reliable tracking of low altitude low profile aerial targets in urban and mountain areas because of reflection and re-reflections from buildings and terrain. They become visible and vulnerable to guided missiles if positioned on a tower or blimp. Doppler radar cannot distinguish moving cars and small low altitude aerial targets in an urban area. A new concept of pocket size distributed radar technology based on the application of UAV (Unmanned Air Vehicles), UGV (Unmanned Ground Vehicles) is proposed for tracking of low altitude low profile aerial targets at short and medium distances for protection of stadium, camp, military facility in urban or mountain areas.

  11. Integrated RF modules for cooperative UGV/UAV tandems

    NASA Astrophysics Data System (ADS)

    Mitra, Atindra K.; Westbrook, Lamar; Corgan, Johnathan; Young, Sean; Nagar, Jogender; Bariagaber, Tedros

    2008-04-01

    This paper addresses a number of design issues that are associated with integrating lightweight and low-cost RF (Radio Frequency) sensors onto small UGV's (Unmanned Ground Vehicles) and UAV's (Unmanned Aerial Vehicles). Modularintegrated RF sub-systems functions that are discussed include lightweight software programmable radar (or software radar) using COTS software radio components and compact microstrip antenna design concepts for low-frequency surface penetration radars. A discussion on the potential for implementing lightweight multi-function RF systems as well as a discussion on novel futuristic concepts that explore the limits of sensor/platform integration is included.

  12. Simulation study of unmanned aerial vehicle communication networks addressing bandwidth disruptions

    NASA Astrophysics Data System (ADS)

    Wei, Sixiao; Ge, Linqiang; Yu, Wei; Chen, Genshe; Pham, Khanh; Blasch, Erik; Shen, Dan; Lu, Chao

    2014-06-01

    To date, Unmanned Aerial Vehicles (UAVs) have been widely used for numerous applications. UAVs can directly connect to ground stations or satellites to transfer data. Multiple UAVs can communicate and cooperate with each other and then construct an ad-hoc network. Multi-UAV systems have the potential to provide reliable and timely services for end users in addition to satellite networks. In this paper, we conduct a simulation study for evaluating the network performance of multi-UAV systems and satellite networks using the ns-2 networking simulation tool. Our simulation results show that UAV communication networks can achieve better network performance than satellite networks and with a lower cost and increased timeliness. We also investigate security resiliency of UAV networks. As a case study, we simulate false data injection attacks against UAV communication networks in ns-2 and demonstrate the impact of false data injection attacks on network performance.

  13. Volcanic Plume Measurements with UAV (Invited)

    NASA Astrophysics Data System (ADS)

    Shinohara, H.; Kaneko, T.; Ohminato, T.

    2013-12-01

    Volatiles in magmas are the driving force of volcanic eruptions and quantification of volcanic gas flux and composition is important for the volcano monitoring. Recently we developed a portable gas sensor system (Multi-GAS) to quantify the volcanic gas composition by measuring volcanic plumes and obtained volcanic gas compositions of actively degassing volcanoes. As the Multi-GAS measures variation of volcanic gas component concentrations in the pumped air (volcanic plume), we need to bring the apparatus into the volcanic plume. Commonly the observer brings the apparatus to the summit crater by himself but such measurements are not possible under conditions of high risk of volcanic eruption or difficulty to approach the summit due to topography etc. In order to overcome these difficulties, volcanic plume measurements were performed by using manned and unmanned aerial vehicles. The volcanic plume measurements by manned aerial vehicles, however, are also not possible under high risk of eruption. The strict regulation against the modification of the aircraft, such as installing sampling pipes, also causes difficulty due to the high cost. Application of the UAVs for the volcanic plume measurements has a big advantage to avoid these problems. The Multi-GAS consists of IR-CO2 and H2O gas analyzer, SO2-H2O chemical sensors and H2 semiconductor sensor and the total weight ranges 3-6 kg including batteries. The necessary conditions of the UAV for the volcanic plumes measurements with the Multi-GAS are the payloads larger than 3 kg, maximum altitude larger than the plume height and installation of the sampling pipe without contamination of the exhaust gases, as the exhaust gases contain high concentrations of H2, SO2 and CO2. Up to now, three different types of UAVs were applied for the measurements; Kite-plane (Sky Remote) at Miyakejima operated by JMA, Unmanned airplane (Air Photo Service) at Shinomoedake, Kirishima volcano, and Unmanned helicopter (Yamaha) at Sakurajima

  14. Use of the RoboFlag synthetic task environment to investigate workload and stress responses in UAV operation.

    PubMed

    Guznov, Svyatoslav; Matthews, Gerald; Funke, Gregory; Dukes, Allen

    2011-09-01

    Use of unmanned aerial vehicles (UAVs) is an increasingly important element of military missions. However, controlling UAVs may impose high stress and workload on the operator. This study evaluated the use of the RoboFlag simulated environment as a means for profiling multiple dimensions of stress and workload response to a task requiring control of multiple vehicles (robots). It tested the effects of two workload manipulations, environmental uncertainty (i.e., UAV's visual view area) and maneuverability, in 64 participants. The findings confirmed that the task produced substantial workload and elevated distress. Dissociations between the stress and performance effects of the manipulations confirmed the utility of a multivariate approach to assessment. Contrary to expectations, distress and some aspects of workload were highest in the low-uncertainty condition, suggesting that overload of information may be an issue for UAV interface designers. The strengths and limitations of RoboFlag as a methodology for investigating stress and workload responses are discussed.

  15. Design and development of a robust ATP subsystem for the Altair UAV-to-Ground lasercomm 2.5 Gbps demonstration

    NASA Technical Reports Server (NTRS)

    Ortiz, G. G.; Lee, S.; Monacos, S.; Wright, M.; Biswas, A.

    2003-01-01

    A robust acquisition, tracking and pointing (ATP) subsystem is being developed for the 2.5 Gigabit per second (Gbps) Unmanned-Aerial-Vehicle (UAV) to ground free-space optical communications link project.

  16. Accuracy evaluation of 3D lidar data from small UAV

    NASA Astrophysics Data System (ADS)

    Tulldahl, H. M.; Bissmarck, Fredrik; Larsson, Hâkan; Grönwall, Christina; Tolt, Gustav

    2015-10-01

    A UAV (Unmanned Aerial Vehicle) with an integrated lidar can be an efficient system for collection of high-resolution and accurate three-dimensional (3D) data. In this paper we evaluate the accuracy of a system consisting of a lidar sensor on a small UAV. High geometric accuracy in the produced point cloud is a fundamental qualification for detection and recognition of objects in a single-flight dataset as well as for change detection using two or several data collections over the same scene. Our work presented here has two purposes: first to relate the point cloud accuracy to data processing parameters and second, to examine the influence on accuracy from the UAV platform parameters. In our work, the accuracy is numerically quantified as local surface smoothness on planar surfaces, and as distance and relative height accuracy using data from a terrestrial laser scanner as reference. The UAV lidar system used is the Velodyne HDL-32E lidar on a multirotor UAV with a total weight of 7 kg. For processing of data into a geographically referenced point cloud, positioning and orientation of the lidar sensor is based on inertial navigation system (INS) data combined with lidar data. The combination of INS and lidar data is achieved in a dynamic calibration process that minimizes the navigation errors in six degrees of freedom, namely the errors of the absolute position (x, y, z) and the orientation (pitch, roll, yaw) measured by GPS/INS. Our results show that low-cost and light-weight MEMS based (microelectromechanical systems) INS equipment with a dynamic calibration process can obtain significantly improved accuracy compared to processing based solely on INS data.

  17. Earth Observations and the Role of UAVs: A Capabilities Assessment

    NASA Technical Reports Server (NTRS)

    Cox, Timothy H.

    2006-01-01

    This three-volume document, based on the draft document located on the website given on page 6, presents the findings of a NASA-led capabilities assessment of Uninhabited Aerial Vehicles (UAVs) for civil (defined as non-DoD) use in Earth observations. Volume 1 is the report that presents the overall assessment and summarizes the data. The second volume contains the appendices and references to address the technologies and capabilities required for viable UAV missions. The third volume is the living portion of this effort and contains the outputs from each of the Technology Working Groups (TWGs) along with the reviews conducted by the Universities Space Research Association (USRA). The focus of this report, intended to complement the Office of the Secretary of Defense UAV Roadmap, is four-fold: 1) To determine and document desired future Earth observation missions for all UAVs based on user-defined needs; 2) To determine and document the technologies necessary to support those missions; 3) To discuss the present state of the art platform capabilities and required technologies, including identifying those in progress, those planned, and those for which no current plans exist; 4) Provide the foundations for development of a comprehensive civil UAV roadmap. It is expected that the content of this report will be updated periodically and used to assess the feasibility of future missions. In addition, this report will provide the foundation to help influence funding decisions to develop those technologies that are considered enabling or necessary but are not contained within approved funding plans. This document is written such that each section will be supported by an Appendix that will give the reader a more detailed discussion of that section's topical materials.

  18. Developments in Airborne Oceanography and Air-Sea Interaction

    NASA Astrophysics Data System (ADS)

    Melville, W. K.

    2014-12-01

    One of the earliest ocean-related flights was that of Amundsen to be first across the North Pole and Arctic from Svalbard to Alaska in the airship Norge in 1926. Twenty five years later Cox & Munk flew a B-17G "Flying Fortress" bomber over Hawaiian waters measuring sea surface slope statistics from photographs of sun glitter and wind speed from a yacht. The value of Cox & Munk's "airborne oceanography" became apparent another twenty five years later with the short-lived Seasat microwave remote-sensing mission, since interpretation of the Seasat data in geophysical variables required scattering theories that relied on their data. The universal acceptance of remote sensing in oceanography began in 1992 with the launch of, and successful analysis of sea surface height data from, the Topex/Poseidon radar altimeter. With that and the development of more realistic coupled atmosphere-ocean models it became apparent that our understanding of weather and climate variability in both the atmosphere and the ocean depends crucially on our ability to measure processes in boundary layers spanning the interface. Ten years ago UNOLS formed the Scientific Committee for Oceanographic Aircraft Research (SCOAR) "...to improve access to research aircraft facilities for ocean sciences"; an attempt to make access to aircraft as easy as access to research vessels. SCOAR emphasized then that "Aircraft are ideal for both fast-response investigations and routine, long-term measurements, and they naturally combine atmospheric measurements with oceanographic measurements on similar temporal and spatial scales." Since then developments in GPS positioning and miniaturization have made scientific measurements possible from smaller and smaller platforms, including the transition from manned to unmanned aerial vehicles (UAVs). Furthermore, ship-launched and recovered UAVs have demonstrated how they can enhance the capabilities and reach of the research vessels, "projecting" research and science

  19. Tracking Forest and Open Area Effects on Snow Accumulation by Unmanned Aerial Vehicle Photogrammetry

    NASA Astrophysics Data System (ADS)

    Lendzioch, T.; Langhammer, J.; Jenicek, M.

    2016-06-01

    Airborne digital photogrammetry is undergoing a renaissance. The availability of low-cost Unmanned Aerial Vehicle (UAV) platforms well adopted for digital photography and progress in software development now gives rise to apply this technique to different areas of research. Especially in determining snow depth spatial distributions, where repetitive mapping of cryosphere dynamics is crucial. Here, we introduce UAV-based digital photogrammetry as a rapid and robust approach for evaluating snow accumulation over small local areas (e.g., dead forest, open areas) and to reveal impacts related to changes in forest and snowpack. Due to the advancement of the technique, snow depth of selected study areas such as of healthy forest, disturbed forest, succession, dead forest, and of open areas can be estimated at a 1 cm spatial resolution. The approach is performed in two steps: 1) developing a high resolution Digital Elevation Model during snow-free and 2) during snow-covered conditions. By substracting these two models the snow depth can be accurately retrieved and volumetric changes of snow depth distribution can be achieved. This is a first proof-of-concept study combining snow depth determination and Leaf Area Index (LAI) retrieval to monitor the impact of forest canopy metrics on snow accumulation in coniferous forest within the Šumava National Park, Czech Republic. Both, downward-looking UAV images and upward-looking LAI-2200 canopy analyser measurements were applied to reveal the LAI, controlling interception and transmitting radiation. For the performance of downward-looking images the snow background instead of the sky fraction was used. In contrast to the classical determination of LAI by hemispherical photography or by LAI plant canopy analyser, our approach will also test the accuracy of LAI measurements by UAV that are taken simultaneously during the snow cover mapping campaigns. Since the LAI parameter is important for snowpack modelling, this method presents

  20. Quality Analysis on 3d Buidling Models Reconstructed from Uav Imagery

    NASA Astrophysics Data System (ADS)

    Jarzabek-Rychard, M.; Karpina, M.

    2016-06-01

    Recent developments in UAV technology and structure from motion techniques have effected that UAVs are becoming standard platforms for 3D data collection. Because of their flexibility and ability to reach inaccessible urban parts, drones appear as optimal solution for urban applications. Building reconstruction from the data collected with UAV has the important potential to reduce labour cost for fast update of already reconstructed 3D cities. However, especially for updating of existing scenes derived from different sensors (e.g. airborne laser scanning), a proper quality assessment is necessary. The objective of this paper is thus to evaluate the potential of UAV imagery as an information source for automatic 3D building modeling at LOD2. The investigation process is conducted threefold: (1) comparing generated SfM point cloud to ALS data; (2) computing internal consistency measures of the reconstruction process; (3) analysing the deviation of Check Points identified on building roofs and measured with a tacheometer. In order to gain deep insight in the modeling performance, various quality indicators are computed and analysed. The assessment performed according to the ground truth shows that the building models acquired with UAV-photogrammetry have the accuracy of less than 18 cm for the plannimetric position and about 15 cm for the height component.

  1. Aerodynamic study on wing and tail small UAV without runways

    NASA Astrophysics Data System (ADS)

    Soetanto, Maria F.; R., Randy; Alfan M., R.; Dzaldi

    2016-06-01

    This paper consists of the design and analysis of the aerodynamics of the profiles of wing and tail of a Small Unmanned Aerial Vehicle (UAV). UAV is a remote-controlled aircraft that can carry cameras, sensors and even weapons on an area that needed aerial photography or aerial video [1]. The aim of this small UAV is for used in situations where manned flight is considered too risky or difficult, such as fire fighting or surveillance, while the term 'small means the design of this UAV has to be relatively small and portable so that peoples are able to carry it during their operations [CASR Part 101.240: it is a UAV which is has a launch mass greater than 100 grams but less than 100 kilograms] [2]. Computational Fluid Dynamic (CFD) method was used to analyze the fluid flow characteristics around the aerofoil's profiles, such as the lift generation for each angle of attack and longitudinal stability caused by vortex generation on trailing edge. Based on the analysis and calculation process, Clark-Y MOD with aspect ratio, AR = 4.28 and taper ratio, λ = 0.65 was chosen as the wing aerofoil and SD 8020 with AR = 4.8 and λ = 0.5 was chosen as the horizontal tail, while SD 8020 with AR = 1.58 and λ = 0.5 was chosen as the vertical tail. The lift and drag forces generated for wing and tail surfaces can be determined from the Fluent 6.3 simulation. Results showed that until angle of attack of 6 degrees, the formation of flow separation is still going on behind the trailing edge, and the stall condition occurs at 14 degrees angle of attack which is characterized by the occurrence of flow separation at leading edge, with a maximum lift coefficient (Cl) obtained = 1.56. The results of flight tests show that this small UAV has successfully maneuvered to fly, such as take off, some acrobatics when cruising and landing smoothly, which means that the calculation and analysis of aerodynamic aerofoil's profile used on the wing and tail of the Small UAV were able to be validated.

  2. Using Natural Language to Enable Mission Managers to Control Multiple Heterogeneous UAVs

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Puig-Navarro, Javier; Mehdi, S. Bilal; Mcquarry, A. Kyle

    2016-01-01

    The availability of highly capable, yet relatively cheap, unmanned aerial vehicles (UAVs) is opening up new areas of use for hobbyists and for commercial activities. This research is developing methods beyond classical control-stick pilot inputs, to allow operators to manage complex missions without in-depth vehicle expertise. These missions may entail several heterogeneous UAVs flying coordinated patterns or flying multiple trajectories deconflicted in time or space to predefined locations. This paper describes the functionality and preliminary usability measures of an interface that allows an operator to define a mission using speech inputs. With a defined and simple vocabulary, operators can input the vast majority of mission parameters using simple, intuitive voice commands. Although the operator interface is simple, it is based upon autonomous algorithms that allow the mission to proceed with minimal input from the operator. This paper also describes these underlying algorithms that allow an operator to manage several UAVs.

  3. Optimal flights of unmanned aerial vehicles utilizing wind energy

    NASA Astrophysics Data System (ADS)

    Qi, Ying

    Unmanned aerial vehicles (UAVs) are attractive for a wide range of applications where human presence is dangerous or undesirable. Endurance is an important performance attribute in many UAV missions. While UAV flight endurance can be improved through advances in aerodynamics and engine design, it is equally important to examine operational strategies that can enhance UAV flight endurance and other performance. Wind energy may be used to greatly enhance the flight endurance and performances of Unmanned Aerial Vehicles. Glider pilots commonly use wind to improve range, endurance, or cross-country speed. Compared with a glider, UAVs have ad vantages in utilizing energy in atmosphere. By using proper strategies to extract wind energy in the long-duration flights, a UAV's fuel consumption can be reduced and the performance can be extended. The objective of this research is to investigate the potential benefits of utilizing wind energy and develop optimal wind energy efficient flight trajectories for UAVs. In this thesis, the potential benefits and features of the autonomous soaring flights are studied. UAVs are modelled with point-mass equations of motion. Practical constraints from UAV performance and operational constraints are considered. UAV flights through various wind patterns including wind gradients, thermals and downbursts are studied. Linear wind gradient models, two-dimensional thermal models and three-dimensional vortex ring downburst models are used for the calculation of optimal trajectories. UAV flights through wind fields are formulated as nonlinear optimal control problems that minimize the overall fuel consumption. These problems are converted into parameter optimizations and numerical solutions are obtained for a wide range of wind conditions and UAV performance parameters. Basic features and special flight patterns needed for wind energy flights are discovered. Results indicate that significant improvements in UAV endurance can be achieved by

  4. Adaptive support vector regression for UAV flight control.

    PubMed

    Shin, Jongho; Jin Kim, H; Kim, Youdan

    2011-01-01

    This paper explores an application of support vector regression for adaptive control of an unmanned aerial vehicle (UAV). Unlike neural networks, support vector regression (SVR) generates global solutions, because SVR basically solves quadratic programming (QP) problems. With this advantage, the input-output feedback-linearized inverse dynamic model and the compensation term for the inversion error are identified off-line, which we call I-SVR (inversion SVR) and C-SVR (compensation SVR), respectively. In order to compensate for the inversion error and the unexpected uncertainty, an online adaptation algorithm for the C-SVR is proposed. Then, the stability of the overall error dynamics is analyzed by the uniformly ultimately bounded property in the nonlinear system theory. In order to validate the effectiveness of the proposed adaptive controller, numerical simulations are performed on the UAV model.

  5. Evaluating the Accuracy of dem Generation Algorithms from Uav Imagery

    NASA Astrophysics Data System (ADS)

    Ruiz, J. J.; Diaz-Mas, L.; Perez, F.; Viguria, A.

    2013-08-01

    In this work we evaluated how the use of different positioning systems affects the accuracy of Digital Elevation Models (DEMs) generated from aerial imagery obtained with Unmanned Aerial Vehicles (UAVs). In this domain, state-of-the-art DEM generation algorithms suffer from typical errors obtained by GPS/INS devices in the position measurements associated with each picture obtained. The deviations from these measurements to real world positions are about meters. The experiments have been carried out using a small quadrotor in the indoor testbed at the Center for Advanced Aerospace Technologies (CATEC). This testbed houses a system that is able to track small markers mounted on the UAV and along the scenario with millimeter precision. This provides very precise position measurements, to which we can add random noise to simulate errors in different GPS receivers. The results showed that final DEM accuracy clearly depends on the positioning information.

  6. UAV platforms for cultural heritage survey: first results

    NASA Astrophysics Data System (ADS)

    Lo Brutto, M.; Garraffa, A.; Meli, P.

    2014-05-01

    The use of Unmanned Aerial Vehicle (UAV) is becoming very common for photogrammetric survey especially due to numerous advantages compared to "traditional" aerial photogrammetry. The work carried out describes the first results obtained using different UAV systems for Cultural Heritage surveys. The study was performed acquiring two different datasets on an archaeological site and a "land art" site respectively. These datasets have different characteristics in relation to the extension of the surveyed areas, the used platform, the flight parameters. A Computer Vision approach has been used to produce 3D models and ortho-images with a very high level of detail. Some tests were also carried out to evaluate the metric accuracy of the images orientations and 3D models.

  7. Moving Obstacle Avoidance for Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Lin, Yucong

    There has been a vast increase in applications of Unmanned Aerial Vehicles (UAVs) in civilian domains. To operate in the civilian airspace, a UAV must be able to sense and avoid both static and moving obstacles for flight safety. While indoor and low-altitude environments are mainly occupied by static obstacles, risks in space of higher altitude primarily come from moving obstacles such as other aircraft or flying vehicles in the airspace. Therefore, the ability to avoid moving obstacles becomes a necessity for Unmanned Aerial Vehicles. Towards enabling a UAV to autonomously sense and avoid moving obstacles, this thesis makes the following contributions. Initially, an image-based reactive motion planner is developed for a quadrotor to avoid a fast approaching obstacle. Furthermore, A Dubin's curve based geometry method is developed as a global path planner for a fixed-wing UAV to avoid collisions with aircraft. The image-based method is unable to produce an optimal path and the geometry method uses a simplified UAV model. To compensate these two disadvantages, a series of algorithms built upon the Closed-Loop Rapid Exploratory Random Tree are developed as global path planners to generate collision avoidance paths in real time. The algorithms are validated in Software-In-the-Loop (SITL) and Hardware-In-the-Loop (HIL) simulations using a fixed-wing UAV model and in real flight experiments using quadrotors. It is observed that the algorithm enables a UAV to avoid moving obstacles approaching to it with different directions and speeds.

  8. A Safe Flight Approach of the UAV in the Electrical Line Inspection

    NASA Astrophysics Data System (ADS)

    Liu, Changan; Liu, Yang; Wu, Hua; Dong, Ruifang

    2015-10-01

    In recent years, the UAV (Unmanned Aerial Vehicle) inspection for the electrical line has received increasing attentions due to the advantages of low costs, easiness to control and flexibility. The UAV can inspect the electrical tower independently and automatically by planning the flight path. But during the inspection along the path, the UAV is easily impacted by gust wind due to its light weight and small size, which always leads to the crash into the electrical tower. Thus, in this paper, a safe flight approach (SFA) is proposed to make the flight be safer during the inspection. The main contributions include: firstly, the piecewise linear interpolation method is proposed to fit the distribution curve of the electrical towers based on the GPS coordinates of the electrical towers; secondly, the no-fly zone on the both sides of the distribution curve are created, and a security distance formula (SDF) is raised to decide the width of the no-fly zone; thirdly, a gust wind formula (GWF) is proposed to improve the artificial potential field approach, which can contribute to the path planning of the UAV; finally, a flight path of the UAV can be planned using the SFA to make the UAV avoid colliding with the electric tower. The proposed approach is tested on the experiment to demonstrate its effectiveness.

  9. Launch of a Vehicle from a Ramp

    ERIC Educational Resources Information Center

    Cross, Rod

    2011-01-01

    A vehicle proceeding up an inclined ramp will become airborne if the ramp comes to a sudden end and if the vehicle fails to stop before it reaches the end of the ramp. A vehicle may also become airborne if it passes over the top of a hill at sufficient speed. In both cases, the vehicle becomes airborne if the point of support underneath the…

  10. Simulation to Flight Test for a UAV Controls Testbed

    NASA Technical Reports Server (NTRS)

    Motter, Mark A.; Logan, Michael J.; French, Michael L.; Guerreiro, Nelson M.

    2006-01-01

    The NASA Flying Controls Testbed (FLiC) is a relatively small and inexpensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches. The most recent version of the FLiC is configured with 16 independent aileron segments, supports the implementation of C-coded experimental controllers, and is capable of fully autonomous flight from takeoff roll to landing, including flight test maneuvers. The test vehicle is basically a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate (AATD) at Fort Eustis, Virginia and NASA Langley Research Center. Several vehicles have been constructed and collectively have flown over 600 successful test flights, including a fully autonomous demonstration at the Association of Unmanned Vehicle Systems International (AUVSI) UAV Demo 2005. Simulations based on wind tunnel data are being used to further develop advanced controllers for implementation and flight test.

  11. An Adaptive Path Planning Algorithm for Cooperating Unmanned Air Vehicles

    SciTech Connect

    Cunningham, C.T.; Roberts, R.S.

    2000-09-12

    An adaptive path planning algorithm is presented for cooperating Unmanned Air Vehicles (UAVs) that are used to deploy and operate land-based sensor networks. The algorithm employs a global cost function to generate paths for the UAVs, and adapts the paths to exceptions that might occur. Examples are provided of the paths and adaptation.

  12. Adaptive path planning algorithm for cooperating unmanned air vehicles

    SciTech Connect

    Cunningham, C T; Roberts, R S

    2001-02-08

    An adaptive path planning algorithm is presented for cooperating Unmanned Air Vehicles (UAVs) that are used to deploy and operate land-based sensor networks. The algorithm employs a global cost function to generate paths for the UAVs, and adapts the paths to exceptions that might occur. Examples are provided of the paths and adaptation.

  13. The remote characterization of vegetation using Unmanned Aerial Vehicle photography

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned Aerial Vehicles (UAVs) can fly in place of piloted aircraft to gather remote sensing information on vegetation characteristics. The type of sensors flown depends on the instrument payload capacity available, so that, depending on the specific UAV, it is possible to obtain video, aerial phot...

  14. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments.

    PubMed

    Vanegas, Fernando; Gonzalez, Felipe

    2016-05-10

    Unmanned Aerial Vehicles (UAV) can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP), so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV), to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios.

  15. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments

    PubMed Central

    Vanegas, Fernando; Gonzalez, Felipe

    2016-01-01

    Unmanned Aerial Vehicles (UAV) can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP), so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV), to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios. PMID:27171096

  16. Enabling UAV Navigation with Sensor and Environmental Uncertainty in Cluttered and GPS-Denied Environments.

    PubMed

    Vanegas, Fernando; Gonzalez, Felipe

    2016-01-01

    Unmanned Aerial Vehicles (UAV) can navigate with low risk in obstacle-free environments using ground control stations that plan a series of GPS waypoints as a path to follow. This GPS waypoint navigation does however become dangerous in environments where the GPS signal is faulty or is only present in some places and when the airspace is filled with obstacles. UAV navigation then becomes challenging because the UAV uses other sensors, which in turn generate uncertainty about its localisation and motion systems, especially if the UAV is a low cost platform. Additional uncertainty affects the mission when the UAV goal location is only partially known and can only be discovered by exploring and detecting a target. This navigation problem is established in this research as a Partially-Observable Markov Decision Process (POMDP), so as to produce a policy that maps a set of motion commands to belief states and observations. The policy is calculated and updated on-line while flying with a newly-developed system for UAV Uncertainty-Based Navigation (UBNAV), to navigate in cluttered and GPS-denied environments using observations and executing motion commands instead of waypoints. Experimental results in both simulation and real flight tests show that the UAV finds a path on-line to a region where it can explore and detect a target without colliding with obstacles. UBNAV provides a new method and an enabling technology for scientists to implement and test UAV navigation missions with uncertainty where targets must be detected using on-line POMDP in real flight scenarios. PMID:27171096

  17. Smart Cruise Control: UAV sensor operator intent estimation and its application

    NASA Astrophysics Data System (ADS)

    Cheng, Hui; Butler, Darren; Kumar, Rakesh

    2006-05-01

    Due to their long endurance, superior mobility and the low risk posed to the pilot and sensor operator, UAVs have become the preferred platform for persistent ISR missions. However, currently most UAV based ISR missions are conducted through manual operation. Event the simplest tasks, such as vehicle tracking, route reconnaissance and site monitoring, need the sensor operator's undivided attention and constant adjustment of the sensor control. The lack of autonomous behaviour greatly limits of the effectiveness and the capability of UAV-based ISR, especially the use of a large number of UAVs simultaneously. Although fully autonomous UAV based ISR system is desirable, it is still a distant dream due to the complexity and diversity of combat and ISR missions. In this paper, we propose a Smart Cruise Control system that can learn UAV sensor operator's intent and use it to complete tasks automatically, such as route reconnaissance and site monitoring. Using an operator attention model, the proposed system can estimate the operator's intent from how they control the sensor (e.g. camera) and the content of the imagery that is acquired. Therefore, for example, from initially manually controlling the UAV sensor to follow a road, the system can learn not only the preferred operation, "tracking", but also the road appearance, "what to track" in real-time. Then, the learnt models of both road and the desired operation can be used to complete the task automatically. We have demonstrated the Smart Cruise Control system using real UAV videos where roads need to be tracked and buildings need to be monitored.

  18. Application of Artificial Intelligence Techniques in Uninhabited Aerial Vehicle Flight

    NASA Technical Reports Server (NTRS)

    Dufrene, Warren R., Jr.

    2004-01-01

    This paper describes the development of an application of Artificial Intelligence (AI) for Unmanned Aerial Vehicle (UAV) control. The project was done as part of the requirements for a class in AI at NOVA Southeastearn University and a beginning project at NASA Wallops Flight Facility for a resilient, robust, and intelligent UAV flight control system. A method is outlined which allows a base level application for applying an Artificial Intelligence method, Fuzzy Logic, to aspects of Control Logic for UAV flight. One element of UAV flight, automated altitude hold, has been implemented and preliminary results displayed.

  19. Application of Artificial Intelligence Techniques in Uninhabitated Aerial Vehicle Flight

    NASA Technical Reports Server (NTRS)

    Dufrene, Warren R., Jr.

    2003-01-01

    This paper describes the development of an application of Artificial Intelligence (AI) for Unmanned Aerial Vehicle (UAV) control. The project was done as part of the requirements for a class in AI at NOVA southeastern University and a beginning project at NASA Wallops Flight Facility for a resilient, robust, and intelligent UAV flight control system. A method is outlined which allows a base level application for applying an Artificial Intelligence method, Fuzzy Logic, to aspects of Control Logic for UAV flight. One element of UAV flight, automated altitude hold, has been implemented and preliminary results displayed.

  20. Airborne Transparencies.

    ERIC Educational Resources Information Center

    Horne, Lois Thommason

    1984-01-01

    Starting from a science project on flight, art students discussed and investigated various means of moving in space. Then they made acetate illustrations which could be used as transparencies. The projection phenomenon made the illustrations look airborne. (CS)

  1. Potential of Uav-Based Laser Scanner and Multispectral Camera Data in Building Inspection

    NASA Astrophysics Data System (ADS)

    Mader, D.; Blaskow, R.; Westfeld, P.; Weller, C.

    2016-06-01

    Conventional building inspection of bridges, dams or large constructions in general is rather time consuming and often cost expensive due to traffic closures and the need of special heavy vehicles such as under-bridge inspection units or other large lifting platforms. In consideration that, an unmanned aerial vehicle (UAV) will be more reliable and efficient as well as less expensive and simpler to operate. The utilisation of UAVs as an assisting tool in building inspections is obviously. Furthermore, light-weight special sensors such as infrared and thermal cameras as well as laser scanner are available and predestined for usage on unmanned aircraft systems. Such a flexible low-cost system is realized in the ADFEX project with the goal of time-efficient object exploration, monitoring and damage detection. For this purpose, a fleet of UAVs, equipped with several sensors for navigation, obstacle avoidance and 3D object-data acquisition, has been developed and constructed. This contribution deals with the potential of UAV-based data in building inspection. Therefore, an overview of the ADFEX project, sensor specifications and requirements of building inspections in general are given. On the basis of results achieved in practical studies, the applicability and potential of the UAV system in building inspection will be presented and discussed.

  2. Use of a UAV-mounted video camera to assess feeding behavior of Raramuri Criollo cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest in use of unmanned aerial vehicles in science has increased in recent years. It is predicted that they will be a preferred remote sensing platform for applications that inform sustainable rangeland management in the future. The objective of this study was to determine whether UAV video moni...

  3. Mapping infectious disease landscapes: unmanned aerial vehicles and epidemiology.

    PubMed

    Fornace, Kimberly M; Drakeley, Chris J; William, Timothy; Espino, Fe; Cox, Jonathan

    2014-11-01

    The potential applications of unmanned aerial vehicles (UAVs), or drones, have generated intense interest across many fields. UAVs offer the potential to collect detailed spatial information in real time at relatively low cost and are being used increasingly in conservation and ecological research. Within infectious disease epidemiology and public health research, UAVs can provide spatially and temporally accurate data critical to understanding the linkages between disease transmission and environmental factors. Using UAVs avoids many of the limitations associated with satellite data (e.g., long repeat times, cloud contamination, low spatial resolution). However, the practicalities of using UAVs for field research limit their use to specific applications and settings. UAVs fill a niche but do not replace existing remote-sensing methods.

  4. Mapping infectious disease landscapes: unmanned aerial vehicles and epidemiology.

    PubMed

    Fornace, Kimberly M; Drakeley, Chris J; William, Timothy; Espino, Fe; Cox, Jonathan

    2014-11-01

    The potential applications of unmanned aerial vehicles (UAVs), or drones, have generated intense interest across many fields. UAVs offer the potential to collect detailed spatial information in real time at relatively low cost and are being used increasingly in conservation and ecological research. Within infectious disease epidemiology and public health research, UAVs can provide spatially and temporally accurate data critical to understanding the linkages between disease transmission and environmental factors. Using UAVs avoids many of the limitations associated with satellite data (e.g., long repeat times, cloud contamination, low spatial resolution). However, the practicalities of using UAVs for field research limit their use to specific applications and settings. UAVs fill a niche but do not replace existing remote-sensing methods. PMID:25443854

  5. New National Capability in NIMR: Rational, Development and application of meteorological sensors for HALE UAV

    NASA Astrophysics Data System (ADS)

    Choi, Reno K. Y.; Min, Seunghyun; Klein, Marian; Ha, Jong-Chul; Cho, Young-Jun; Cho, ChunHo

    2015-04-01

    Joint Civilian-Military Committee, under Advisory Council on Science and Technology, awarded an ambitious technology demonstration project to build a HALE (High-Altitude Long Endurance) UAV (Unmanned Aerial Vehicle) till 2017. NIMR (National Institute of Meteorological Research) is responsible for developing a payload for meteorological observation, which the committee welcomed not only for technological challenges but also for scientific advances for all parties. NIMR is also responsible for providing numerical weather predictions for flight safety for overall project. HALE UAV is an aircraft that aims to operate at lower stratospheric altitudes for days and weeks. It is an altitude where air becomes thin to prevent operation of conventional jet engines and only military reconnaissance aircrafts have reached at this high or above around 18~21km Since only a couple of unmanned aircraft demonstrated its potential scientific value, atmospheric research at stratospheric altitude offers unique opportunity of monitoring complete troposphere at close range. With advantages from both satellite (consistent observation) and airborne platforms (spatial flexibility), i.e. pseudo-satellite, water content monitoring in the atmosphere enables us to improve prediction of entire life cycle of tropical storms and torrential rains and snows, in addition to better understanding of tropopause dynamics and its prediction capability. This meteorological instrument challenges very limited payload design requirements, i.e. 4kg of weight and 50W of power consumption. With such constraints, NIMR determines to develop passive microwave radiometers (15~100GHz) onboard in the interest of 3D water vapor profiles, along with optical camera for cloud observation. There are number of technical challenges to achieve the goal, such as 1) mechanical and electronic design that works in -75°C and 60hPa with weight and power constraints, and 2) miniaturisation of conventional meteorological instruments

  6. A Turbine-powered UAV Controls Testbed

    NASA Technical Reports Server (NTRS)

    Motter, Mark A.; High, James W.; Guerreiro, Nelson M.; Chambers, Ryan S.; Howard, Keith D.

    2007-01-01

    The latest version of the NASA Flying Controls Testbed (FLiC) integrates commercial-off-the-shelf components including airframe, autopilot, and a small turbine engine to provide a low cost experimental flight controls testbed capable of sustained speeds up to 200 mph. The series of flight tests leading up to the demonstrated performance of the vehicle in sustained, autopiloted 200 mph flight at NASA Wallops Flight Facility's UAV runway in August 2006 will be described. Earlier versions of the FLiC were based on a modified Army target drone, AN/FQM-117B, developed as part of a collaboration between the Aviation Applied Technology Directorate at Fort Eustis, Virginia and NASA Langley Research Center. The newer turbine powered platform (J-FLiC) builds on the successes using the relatively smaller, slower and less expensive unmanned aerial vehicle developed specifically to test highly experimental flight control approaches with the implementation of C-coded experimental controllers. Tracking video was taken during the test flights at Wallops and will be available for presentation at the conference. Analysis of flight data from both remotely piloted and autopiloted flights will be presented. Candidate experimental controllers for implementation will be discussed. It is anticipated that flight testing will resume in Spring 2007 and those results will be included, if possible.

  7. Unmanned Aerial Vehicles unique cost estimating requirements

    NASA Astrophysics Data System (ADS)

    Malone, P.; Apgar, H.; Stukes, S.; Sterk, S.

    Unmanned Aerial Vehicles (UAVs), also referred to as drones, are aerial platforms that fly without a human pilot onboard. UAVs are controlled autonomously by a computer in the vehicle or under the remote control of a pilot stationed at a fixed ground location. There are a wide variety of drone shapes, sizes, configurations, complexities, and characteristics. Use of these devices by the Department of Defense (DoD), NASA, civil and commercial organizations continues to grow. UAVs are commonly used for intelligence, surveillance, reconnaissance (ISR). They are also use for combat operations, and civil applications, such as firefighting, non-military security work, surveillance of infrastructure (e.g. pipelines, power lines and country borders). UAVs are often preferred for missions that require sustained persistence (over 4 hours in duration), or are “ too dangerous, dull or dirty” for manned aircraft. Moreover, they can offer significant acquisition and operations cost savings over traditional manned aircraft. Because of these unique characteristics and missions, UAV estimates require some unique estimating methods. This paper describes a framework for estimating UAV systems total ownership cost including hardware components, software design, and operations. The challenge of collecting data, testing the sensitivities of cost drivers, and creating cost estimating relationships (CERs) for each key work breakdown structure (WBS) element is discussed. The autonomous operation of UAVs is especially challenging from a software perspective.

  8. Semiautonomous Avionics-and-Sensors System for a UAV

    NASA Technical Reports Server (NTRS)

    Shams, Qamar

    2006-01-01

    Unmanned Aerial Vehicles (UAVs) autonomous or remotely controlled pilotless aircraft have been recently thrust into the spotlight for military applications, for homeland security, and as test beds for research. In addition to these functions, there are many space applications in which lightweight, inexpensive, small UAVS can be used e.g., to determine the chemical composition and other qualities of the atmospheres of remote planets. Moreover, on Earth, such UAVs can be used to obtain information about weather in various regions; in particular, they can be used to analyze wide-band acoustic signals to aid in determining the complex dynamics of movement of hurricanes. The Advanced Sensors and Electronics group at Langley Research Center has developed an inexpensive, small, integrated avionics-and-sensors system to be installed in a UAV that serves two purposes. The first purpose is to provide flight data to an AI (Artificial Intelligence) controller as part of an autonomous flight-control system. The second purpose is to store data from a subsystem of distributed MEMS (microelectromechanical systems) sensors. Examples of these MEMS sensors include humidity, temperature, and acoustic sensors, plus chemical sensors for detecting various vapors and other gases in the environment. The critical sensors used for flight control are a differential- pressure sensor that is part of an apparatus for determining airspeed, an absolute-pressure sensor for determining altitude, three orthogonal accelerometers for determining tilt and acceleration, and three orthogonal angular-rate detectors (gyroscopes). By using these eight sensors, it is possible to determine the orientation, height, speed, and rates of roll, pitch, and yaw of the UAV. This avionics-and-sensors system is shown in the figure. During the last few years, there has been rapid growth and advancement in the technological disciplines of MEMS, of onboard artificial-intelligence systems, and of smaller, faster, and

  9. Unmanned Airborne Platforms for Validation of Volcanic Emission Composition and Transport Models

    NASA Astrophysics Data System (ADS)

    Pieri, D. C.; Diaz, J. A.; Bland, G.; Fladeland, M. M.

    2012-12-01

    In recent years there has been an increasing realization that current remote sensing retrieval and transport models to detect, characterize, and track airborne volcanic emissions will be much improved fundamentally, and in their application, by the acquisition of in situ validation data. This issue was highlighted by the need for operational estimates of airborne ash concentrations during the 2010 eruption at Eyjafjallajökull-Fimmvörduháls in Iceland. In response, important campaigns were mounted in Europe to conduct airborne in situ observations with manned aircraft to validate ash concentration estimates based on remote sensing data. This effort had immediate application providing crucial accuracy and precision estimates for predicting locations, trajectories, and concentrations of the drifting ash to mitigate the severe economic impacts caused by the continent-wide grounding of aircraft. Manned flying laboratories, however, sustain serious risks if flown into the areas of volcanic plumes and drifting clouds that are of the highest interest, namely the zones of most concentrated ash and gas, which are often opaque to upwelling radiation at the longer infrared wavelengths (e.g., 8-12μm), where ash and gas can be most readily detected. Unmanned airborne vehicles (UAVs), of course, can provide volcanic aerosol and gas sampling and measurement platforms with no risk to flight crews, and can penetrate the most ash-concentrated zones of plumes and drifting clouds. Current interest has been high in developing and testing small UAVs (e.g., NASA, University of Costa Rica, University of Düsseldorf; INGV-Catania and Rome, and others) for proximal sulfur dioxide and solid aerosol observations and sampling in relatively quiescently erupting plumes as a first step toward more far ranging and higher altitude deployments into drifting volcanic ash clouds at regional scales. Nevertheless, in the aftermath of the Icelandic crisis, ash and gas concentrations from analysis of

  10. Pricise Target Geolocation and Tracking Based on Uav Video Imagery

    NASA Astrophysics Data System (ADS)

    Hosseinpoor, H. R.; Samadzadegan, F.; Dadrasjavan, F.

    2016-06-01

    There is an increasingly large number of applications for Unmanned Aerial Vehicles (UAVs) from monitoring, mapping and target geolocation. However, most of commercial UAVs are equipped with low-cost navigation sensors such as C/A code GPS and a low-cost IMU on board, allowing a positioning accuracy of 5 to 10 meters. This low accuracy cannot be used in applications that require high precision data on cm-level. This paper presents a precise process for geolocation of ground targets based on thermal video imagery acquired by small UAV equipped with RTK GPS. The geolocation data is filtered using an extended Kalman filter, which provides a smoothed estimate of target location and target velocity. The accurate geo-locating of targets during image acquisition is conducted via traditional photogrammetric bundle adjustment equations using accurate exterior parameters achieved by on board IMU and RTK GPS sensors, Kalman filtering and interior orientation parameters of thermal camera from pre-flight laboratory calibration process. The results of this study compared with code-based ordinary GPS, indicate that RTK observation with proposed method shows more than 10 times improvement of accuracy in target geolocation.

  11. Miniaturized hyperspectral imager calibration and UAV flight campaigns

    NASA Astrophysics Data System (ADS)

    Saari, Heikki; Pölönen, Ilkka; Salo, Heikki; Honkavaara, Eija; Hakala, Teemu; Holmlund, Christer; Mäkynen, Jussi; Mannila, Rami; Antila, Tapani; Akujärvi, Altti

    2013-10-01

    VTT Technical Research Centre of Finland has developed Tunable Fabry-Perot Interferometer (FPI) based miniaturized hyperspectral imager which can be operated from light weight Unmanned Aerial Vehicles (UAV). The concept of the hyperspectral imager has been published in the SPIE Proc. 7474, 8174 and 8374. This instrument requires dedicated laboratory and on-board calibration procedures which are described. During summer 2012 extensive UAV Hyperspectral imaging campaigns in the wavelength range 400 - 900 nm at resolution range 10 - 40 nm @ FWHM were performed to study forest inventory, crop biomass and nitrogen distributions and environmental status of natural water applications. The instrument includes spectral band limiting filters which can be used for the on-board wavelength scale calibration by scanning the FPI pass band center wavelength through the low and high edge of the operational wavelength band. The procedure and results of the calibration tests will be presented. A short summary of the performed extensive UAV imaging campaign during summer 2012 will be presented.

  12. Guidance and Control of an Autonomous Soaring UAV

    NASA Technical Reports Server (NTRS)

    Allen, Michael J.

    2007-01-01

    Thermals caused by convection in the lower atmosphere are commonly used by birds and glider pilots to extend flight duration, increase cross-country speed, improve range, or simply to conserve energy. Uninhabited Aerial Vehicles (UAVs) can also increase performance and reduce energy consumption by exploiting atmospheric convection. An autonomous soaring research project was conducted at the NASA Dryden Flight Research Center to evaluate the concept through flight test of an electric-powered motor-glider with a wingspan of 4.27 m (14 ft). The UAV's commercial autopilot software was modified to include outer-loop soaring guidance and control. The aircraft total energy state was used to detect and soar within thermals. Estimated thermal size and position were used to calculate guidance commands for soaring flight. Results from a total of 23 thermal encounters show good performance of the guidance and control algorithms to autonomously detect and exploit thermals. The UAV had an average climb of 172 m (567 ft) during these encounters.

  13. Guidance and Control of an Autonomous Soaring UAV

    NASA Technical Reports Server (NTRS)

    Allen, Michael J.; Lin, Victor

    2007-01-01

    Thermals caused by convection in the lower atmosphere are commonly used by birds and glider pilots to extend flight duration, increase cross-country speed, improve range, or simply to conserve energy. Uninhabited Aerial Vehicles (UAVs) can also increase performance and reduce energy consumption by exploiting atmospheric convection. An autonomous soaring research project was conducted at the NASA Dryden Flight Research Center to evaluate the concept through flight test of an electric-powered motorglider with a wingspan of 4.27 m (14 ft). The UAV's commercial autopilot software was modified to include outer-loop soaring guidance and control. The aircraft total energy state was used to detect and soar within thermals. Estimated thermal size and position were used to calculate guidance commands for soaring flight. Results from a total of 23 thermal encounters show good performance of the guidance and control algorithms to autonomously detect and exploit thermals. The UAV had an average climb of 172 m (567 ft) during these encounters.

  14. a Micro-Uav with the Capability of Direct Georeferencing

    NASA Astrophysics Data System (ADS)

    Rehak, M.; Mabillard, R.; Skaloud, J.

    2013-08-01

    This paper presents the development of a low cost UAV (Unmanned Aerial Vehicle) with the capability of direct georeferencing. The advantage of such system lies in its high maneuverability, operation flexibility as well as capability to acquire image data without the need of establishing ground control points (GCPs). Moreover, the precise georeferencing offers an improvement in the final mapping accuracy when employing integrated sensor orientation. Such mode of operation limits the number and distribution of GCPs, which in turns save time in their signalization and surveying. Although the UAV systems feature high flexibility and capability of flying into areas that are inhospitable or inaccessible to humans, the lack of precision in positioning and attitude estimation on-board decrease the gained value of the captured imagery and limits their mode of operation to specific configurations and need of groundreference. Within a scope of this study we show the potential of present technologies in the field of position and orientation determination on a small UAV. The hardware implementation and especially the non-trivial synchronization of all components is clarified. Thanks to the implementation of a multi-frequency, low power GNSS receiver and its coupling with redundant MEMSIMU, we can attain the characteristic of a much larger systems flown on large carries while keeping the sensor size and weight suitable for MAV operations.

  15. Automated Dsm Extraction from Uav Images and Performance Analysis

    NASA Astrophysics Data System (ADS)

    Rhee, S.; Kim, T.

    2015-08-01

    As technology evolves, unmanned aerial vehicles (UAVs) imagery is being used from simple applications such as image acquisition to complicated applications such as 3D spatial information extraction. Spatial information is usually provided in the form of a DSM or point cloud. It is important to generate very dense tie points automatically from stereo images. In this paper, we tried to apply stereo image-based matching technique developed for satellite/aerial images to UAV images, propose processing steps for automated DSM generation and to analyse the possibility of DSM generation. For DSM generation from UAV images, firstly, exterior orientation parameters (EOPs) for each dataset were adjusted. Secondly, optimum matching pairs were determined. Thirdly, stereo image matching was performed with each pair. Developed matching algorithm is based on grey-level correlation on pixels applied along epipolar lines. Finally, the extracted match results were united with one result and the final DSM was made. Generated DSM was compared with a reference DSM from Lidar. Overall accuracy was 1.5 m in NMAD. However, several problems have to be solved in future, including obtaining precise EOPs, handling occlusion and image blurring problems. More effective interpolation technique needs to be developed in the future.

  16. a New Approach to Fast Mosaic Uav Images

    NASA Astrophysics Data System (ADS)

    Liu, Q.; Liu, W.; Zou, L.; Wang, J.; Liu, Y.

    2011-09-01

    Unmanned Aerial Vehicles (UAVs) have been widely used to acquire high quality terrain images of the areas of interest, particularly when such a task could potentially risk human life or even impossible as the areas cannot be accessed easily by surveyors. Once the images have been obtained, traditional photogrammetric processing process can be used to establish a relative orientation model and then, absolute orientation model with the procedures of space resection and intersection. In many such applications, the geo- referenced images which are stitched together to represent the geospatial relationships for the feature objects are sufficient. A fast or near real-time processing approach for UAV images using GPS/INS data has being investigated for years. One beneficial application of such approach is the capability of quick production of geo-referenced images for various engineering or business activities, such as urban and road planning, the site selection of factories and bridges, etc. In this paper, we have proposed a new fast processing approach for the UAV images collected with an integrated GPS/INS/Vision system. The approach features that the corresponding points between images have been determined, and then coordinate transformation is carried out to implement image stitching. The accuracy of corresponding points normally affects the quality of stitched images, but the results of our experiments revealed that the image stitching errors were obvious even the accuracy of corresponding points was high. The stitching errors could be caused by the changes of surface elevation.

  17. Uav-Based Automatic Tree Growth Measurement for Biomass Estimation

    NASA Astrophysics Data System (ADS)

    Karpina, M.; Jarząbek-Rychard, M.; Tymków, P.; Borkowski, A.

    2016-06-01

    Manual in-situ measurements of geometric tree parameters for the biomass volume estimation are time-consuming and economically non-effective. Photogrammetric techniques can be deployed in order to automate the measurement procedure. The purpose of the presented work is an automatic tree growth estimation based on Unmanned Aircraft Vehicle (UAV) imagery. The experiment was conducted in an agriculture test field with scots pine canopies. The data was collected using a Leica Aibotix X6V2 platform equipped with a Nikon D800 camera. Reference geometric parameters of selected sample plants were measured manually each week. In situ measurements were correlated with the UAV data acquisition. The correlation aimed at the investigation of optimal conditions for a flight and parameter settings for image acquisition. The collected images are processed in a state of the art tool resulting in a generation of dense 3D point clouds. The algorithm is developed in order to estimate geometric tree parameters from 3D points. Stem positions and tree tops are identified automatically in a cross section, followed by the calculation of tree heights. The automatically derived height values are compared to the reference measurements performed manually. The comparison allows for the evaluation of automatic growth estimation process. The accuracy achieved using UAV photogrammetry for tree heights estimation is about 5cm.

  18. Uav Positioning and Collision Avoidance Based on RSS Measurements

    NASA Astrophysics Data System (ADS)

    Masiero, A.; Fissore, F.; Guarnieri, A.; Pirotti, F.; Vettore, A.

    2015-08-01

    In recent years, Unmanned Aerial Vehicles (UAVs) are attracting more and more attention in both the research and industrial communities: indeed, the possibility to use them in a wide range of remote sensing applications makes them a very flexible and attractive solution in both civil and commercial cases (e.g. precision agriculture, security and control, monitoring of sites, exploration of areas difficult to reach). Most of the existing UAV positioning systems rely on the use of the GPS signal. Despite this can be a satisfactory solution in open environments where the GPS signal is available, there are several operating conditions of interest where it is unavailable or unreliable (e.g. close to high buildings, or mountains, in indoor environments). Consequently, a different approach has to be adopted in these cases. This paper considers the use ofWiFi measurements in order to obtain position estimations of the device of interest. More specifically, to limit the costs for the devices involved in the positioning operations, an approach based on radio signal strengths (RSS) measurements is considered. Thanks to the use of a Kalman filter, the proposed approach takes advantage of the temporal dynamic of the device of interest in order to improve the positioning results initially provided by means of maximum likelihood estimations. The considered UAVs are assumed to be provided with communication devices, which can allow them to communicate with each other in order to improve their cooperation abilities. In particular, the collision avoidance problem is examined in this work.

  19. Simulation assessment of synthetic vision system concepts for UAV operations

    NASA Astrophysics Data System (ADS)

    Calhoun, Gloria L.; Draper, Mark H.; Ruff, Heath A.; Nelson, Jeremy T.; Lefebvre, Austen T.

    2006-05-01

    The Air Force Research Laboratory's Human Effectiveness Directorate supports research addressing human factors associated with Unmanned Aerial Vehicle (UAV) operator control stations. One research thrust explores the value of combining synthetic vision data with live camera video presented on a UAV control station display. Information is constructed from databases (e.g., terrain, etc.), as well as numerous information updates via networked communication with other sources. This information is overlaid conformal, in real time, onto the dynamic camera video image display presented to operators. Synthetic vision overlay technology is expected to improve operator situation awareness by highlighting elements of interest within the video image. Secondly, it can assist the operator in maintaining situation awareness of an environment if the video datalink is temporarily degraded. Synthetic vision overlays can also serve to facilitate intuitive communications of spatial information between geographically separated users. This paper discusses results from a high-fidelity UAV simulation evaluation of synthetic symbology overlaid on a (simulated) live camera display. Specifically, the effects of different telemetry data update rates for synthetic visual data were examined for a representative sensor operator task. Participants controlled the zoom and orientation of the camera to find and designate targets. The results from both performance and subjective data demonstrated the potential benefit of an overlay of synthetic symbology for improving situation awareness, reducing workload, and decreasing time required to designate points of interest. Implications of symbology update rate are discussed, as well as other human factors issues.

  20. Atmospheric Radiation Measurement Program - unmanned aerospace vehicle: The follow-on phase

    SciTech Connect

    Vitko, J. Jr.

    1995-04-01

    Unmanned Aerospace Vehicle (UAV) demonstration flights (UDF) are designed to provide an early demonstration of the scientific utility of UAVs by using an existing UAV and instruments to measure broadband radiative flux profiles under clear sky conditions. UDF is but the first of three phases of ARM-UAV. The second phase significantly extends both the UAV measurement techniques and the available instrumentation to allow both multi-UAV measurements in cloudy skies and extended duration measurements in the tropopause. These activities build naturally to the third and final phase, that of full operational capability, i.e., UAVs capable of autonomous operations at 20-km altitudes for multiple days with a full suite of instrumentation for measuring radiative flux, cloud properties, and water vapor profiles.

  1. Technology Challenges in Small UAV Development

    NASA Technical Reports Server (NTRS)

    Logan, Michael J.; Vranas, Thomas L.; Motter, Mark; Shams, Qamar; Pollock, Dion S.

    2005-01-01

    Development of highly capable small UAVs present unique challenges for technology protagonists. Size constraints, the desire for ultra low cost and/or disposable platforms, lack of capable design and analysis tools, and unique mission requirements all add to the level of difficulty in creating state-of-the-art small UAVs. This paper presents the results of several small UAV developments, the difficulties encountered, and proposes a list of technology shortfalls that need to be addressed.

  2. Fourth Airborne Geoscience Workshop

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The focus of the workshop was on how the airborne community can assist in achieving the goals of the Global Change Research Program. The many activities that employ airborne platforms and sensors were discussed: platforms and instrument development; airborne oceanography; lidar research; SAR measurements; Doppler radar; laser measurements; cloud physics; airborne experiments; airborne microwave measurements; and airborne data collection.

  3. In situ Volcanic Plume Monitoring with small Unmanned Aerial Systems for Cal/Val of Satellite Remote Sensing Data: CARTA-UAV 2013 Mission (Invited)

    NASA Astrophysics Data System (ADS)

    Diaz, J. A.; Pieri, D. C.; Bland, G.; Fladeland, M. M.

    2013-12-01

    The development of small unmanned aerial systems (sUAS) with a variety of sensor packages, enables in situ and proximal remote sensing measurements of volcanic plumes. Using Costa Rican volcanoes as a Natural Laboratory, the University of Costa Rica as host institution, in collaboration with four NASA centers, have started an initiative to develop low-cost, field-deployable airborne platforms to perform volcanic gas & ash plume research, and in-situ volcanic monitoring in general, in conjunction with orbital assets and state-of-the-art models of plume transport and composition. Several gas sensors have been deployed into the active plume of Turrialba Volcano including a miniature mass spectrometer, and an electrochemical SO2 sensor system with temperature, pressure, relative humidity, and GPS sensors. Several different airborne platforms such as manned research aircraft, unmanned aerial vehicles, tethered balloons, as well as man-portable in-situ ground truth systems are being used for this research. Remote sensing data is also collected from the ASTER and OMI spaceborne instruments and compared with in situ data. The CARTA-UAV 2013 Mission deployment and follow up measurements successfully demonstrated a path to study and visualize gaseous volcanic emissions using mass spectrometer and gas sensor based instrumentation in harsh environment conditions to correlate in situ ground/airborne data with remote sensing satellite data for calibration and validation purposes. The deployment of such technology improves on our current capabilities to detect, analyze, monitor, model, and predict hazards presented to aircraft by volcanogenic ash clouds from active and impending volcanic eruptions.

  4. Beach Volume Change Using Uav Photogrammetry Songjung Beach, Korea

    NASA Astrophysics Data System (ADS)

    Yoo, C. I.; Oh, T. S.

    2016-06-01

    Natural beach is controlled by many factors related to wave and tidal forces, wind, sediment, and initial topography. For this reason, if numerous topographic data of beach is accurately collected, coastal erosion/acceleration is able to be assessed and clarified. Generally, however, many studies on coastal erosion have limitation to analyse the whole beach, carried out of partial area as like shoreline (horizontal 2D) and beach profile (vertical 2D) on account of limitation of numerical simulation. This is an important application for prevention of coastal erosion, and UAV photogrammetry is also used to 3D topographic data. This paper analyses the use of unmanned aerial vehicles (UAV) to 3D map and beach volume change. UAV (Quadcopter) equipped with a non-metric camera was used to acquire images in Songjung beach which is located south-east Korea peninsula. The dynamics of beach topography, its geometric properties and estimates of eroded and deposited sand volumes were determined by combining elevation data with quarterly RTK-VRS measurements. To explore the new possibilities for assessment of coastal change we have developed a methodology for 3D analysis of coastal topography evolution based on existing high resolution elevation data combined with low coast, UAV and on-ground RTK-VRS surveys. DSMs were obtained by stereo-matching using Agisoft Photoscan. Using GCPs the vertical accuracy of the DSMs was found to be 10 cm or better. The resulting datasets were integrated in a local coordinates and the method proved to be a very useful fool for the detection of areas where coastal erosion occurs and for the quantification of beach change. The value of such analysis is illustrated by applications to coastal of South Korea sites that face significant management challenges.

  5. Evaluating the effectiveness of low cost UAV generated topography for geomorphic change detection

    NASA Astrophysics Data System (ADS)

    Cook, K. L.

    2014-12-01

    With the recent explosion in the use and availability of unmanned aerial vehicle platforms and development of easy to use structure from motion software, UAV based photogrammetry is increasingly being adopted to produce high resolution topography for the study of surface processes. UAV systems can vary substantially in price and complexity, but the tradeoffs between these and the quality of the resulting data are not well constrained. We look at one end of this spectrum and evaluate the effectiveness of a simple low cost UAV setup for obtaining high resolution topography in a challenging field setting. Our study site is the Daan River gorge in western Taiwan, a rapidly eroding bedrock gorge that we have monitored with terrestrial Lidar since 2009. The site presents challenges for the generation and analysis of high resolution topography, including vertical gorge walls, vegetation, wide variation in surface roughness, and a complicated 3D morphology. In order to evaluate the accuracy of the UAV-derived topography, we compare it with terrestrial Lidar data collected during the same survey period. Our UAV setup combines a DJI Phantom 2 quadcopter with a 16 megapixel Canon Powershot camera for a total platform cost of less than $850. The quadcopter is flown manually, and the camera is programmed to take a photograph every 5 seconds, yielding 200-250 pictures per flight. We measured ground control points and targets for both the Lidar scans and the aerial surveys using a Leica RTK GPS with 1-2 cm accuracy. UAV derived point clouds were obtained using Agisoft Photoscan software. We conducted both Lidar and UAV surveys before and after a summer typhoon season, allowing us to evaluate the reliability of the UAV survey to detect geomorphic changes in the range of one to several meters. We find that this simple UAV setup can yield point clouds with an average accuracy on the order of 10 cm compared to the Lidar point clouds. Well-distributed and accurately located ground

  6. a Comparison of Uav and Tls Data for Soil Roughness Assessment

    NASA Astrophysics Data System (ADS)

    Milenković, M.; Karel, W.; Ressl, C.; Pfeifer, N.

    2016-06-01

    Soil roughness represents fine-scale surface geometry which figures in many geophysical models. While static photogrammetric techniques (terrestrial images and laser scanning) have been recently proposed as a new source for deriving roughness heights, there is still need to overcome acquisition scale and viewing geometry issues. By contrast to the static techniques, images taken from unmanned aerial vehicles (UAV) can maintain near-nadir looking geometry over scales of several agricultural fields. This paper presents a pilot study on high-resolution, soil roughness reconstruction and assessment from UAV images over an agricultural plot. As a reference method, terrestrial laser scanning (TLS) was applied on a 10 m x 1.5 m subplot. The UAV images were self-calibrated and oriented within a bundle adjustment, and processed further up to a dense-matched digital surface model (DSM). The analysis of the UAV- and TLS-DSMs were performed in the spatial domain based on the surface autocorrelation function and the correlation length, and in the frequency domain based on the roughness spectrum and the surface fractal dimension (spectral slope). The TLS- and UAV-DSM differences were found to be under ±1 cm, while the UAV DSM showed a systematic pattern below this scale, which was explained by weakly tied sub-blocks of the bundle block. The results also confirmed that the existing TLS methods leads to roughness assessment up to 5 mm resolution. However, for our UAV data, this was not possible to achieve, though it was shown that for spatial scales of 12 cm and larger, both methods appear to be usable. Additionally, this paper suggests a method to propagate measurement errors to the correlation length.

  7. Neural network-based optimal adaptive output feedback control of a helicopter UAV.

    PubMed

    Nodland, David; Zargarzadeh, Hassan; Jagannathan, Sarangapani

    2013-07-01

    Helicopter unmanned aerial vehicles (UAVs) are widely used for both military and civilian operations. Because the helicopter UAVs are underactuated nonlinear mechanical systems, high-performance controller design for them presents a challenge. This paper introduces an optimal controller design via an output feedback for trajectory tracking of a helicopter UAV, using a neural network (NN). The output-feedback control system utilizes the backstepping methodology, employing kinematic and dynamic controllers and an NN observer. The online approximator-based dynamic controller learns the infinite-horizon Hamilton-Jacobi-Bellman equation in continuous time and calculates the corresponding optimal control input by minimizing a cost function, forward-in-time, without using the value and policy iterations. Optimal tracking is accomplished by using a single NN utilized for the cost function approximation. The overall closed-loop system stability is demonstrated using Lyapunov analysis. Finally, simulation results are provided to demonstrate the effectiveness of the proposed control design for trajectory tracking.

  8. AVALON: definition and modeling of a vertical takeoff and landing UAV

    NASA Astrophysics Data System (ADS)

    Silva, N. B. F.; Marconato, E. A.; Branco, K. R. L. J. C.

    2015-09-01

    Unmanned Aerial Vehicles (UAVs) have been used in numerous applications, like remote sensing, precision agriculture and atmospheric data monitoring. Vertical takeoff and landing (VTOL) is a modality of these aircrafts, which are capable of taking off and landing vertically, like a helicopter. This paper presents the definition and modeling of a fixed- wing VTOL, named AVALON (Autonomous VerticAL takeOff and laNding), which has the advantages of traditional aircrafts with improved performance and can take off and land in small areas. The principles of small UAVs development were followed to achieve a better design and to increase the range of applications for this VTOL. Therefore, we present the design model of AVALON validated in a flight simulator and the results show its validity as a physical option for an UAV platform.

  9. Research on a UAV path planning method for ground observation based on threat sources

    NASA Astrophysics Data System (ADS)

    Yan, Hao; Fan, Xing; Xia, Xuezhi; Lin, Linshu

    2008-12-01

    The path planning method is one of the main research directions in current UAV(unmanned aerial vehicle) technologies. In this paper we perform analyses on the adversarial environment which may be broken through during the UAV mission for ground observation, and carry out the grade classification according to the threat level. On the basis of genetic algorithm, the encoding method of dimension reduction and direct quantization is used to combine the threat value of each leg with the flight distance, so as to construct the fitness evaluation function based on the threat amount and design the algorithm. This method is proven to be able to converge effectively and quickly via the simulation experiments, which meet the threat restriction and applicability of UAV in route planning.

  10. A PSO-PID quaternion model based trajectory control of a hexarotor UAV

    NASA Astrophysics Data System (ADS)

    Artale, Valeria; Milazzo, Cristina L. R.; Orlando, Calogero; Ricciardello, Angela

    2015-12-01

    A quaternion based trajectory controller for a prototype of an Unmanned Aerial Vehicle (UAV) is discussed in this paper. The dynamics of the UAV, a hexarotor in details, is described in terms of quaternion instead of the usual Euler angle parameterization. As UAV flight management concerns, the method here implemented consists of two main steps: trajectory and attitude control via Proportional-Integrative-Derivative (PID) and Proportional-Derivative (PD) technique respectively and the application of Particle Swarm Optimization (PSO) method in order to tune the PID and PD parameters. The optimization is the consequence of the minimization of a objective function related to the error with the respect to a proper trajectory. Numerical simulations support and validate the proposed method.

  11. Airborne Imagery

    NASA Technical Reports Server (NTRS)

    1983-01-01

    ATM (Airborne Thematic Mapper) was developed for NSTL (National Space Technology Companies) by Daedalus Company. It offers expanded capabilities for timely, accurate and cost effective identification of areas with prospecting potential. A related system is TIMS, Thermal Infrared Multispectral Scanner. Originating from Landsat 4, it is also used for agricultural studies, etc.

  12. Uav Photogrammetry: Block Triangulation Comparisons

    NASA Astrophysics Data System (ADS)

    Gini, R.; Pagliari, D.; Passoni, D.; Pinto, L.; Sona, G.; Dosso, P.

    2013-08-01

    UAVs systems represent a flexible technology able to collect a big amount of high resolution information, both for metric and interpretation uses. In the frame of experimental tests carried out at Dept. ICA of Politecnico di Milano to validate vector-sensor systems and to assess metric accuracies of images acquired by UAVs, a block of photos taken by a fixed wing system is triangulated with several software. The test field is a rural area included in an Italian Park ("Parco Adda Nord"), useful to study flight and imagery performances on buildings, roads, cultivated and uncultivated vegetation. The UAV SenseFly, equipped with a camera Canon Ixus 220HS, flew autonomously over the area at a height of 130 m yielding a block of 49 images divided in 5 strips. Sixteen pre-signalized Ground Control Points, surveyed in the area through GPS (NRTK survey), allowed the referencing of the block and accuracy analyses. Approximate values for exterior orientation parameters (positions and attitudes) were recorded by the flight control system. The block was processed with several software: Erdas-LPS, EyeDEA (Univ. of Parma), Agisoft Photoscan, Pix4UAV, in assisted or automatic way. Results comparisons are given in terms of differences among digital surface models, differences in orientation parameters and accuracies, when available. Moreover, image and ground point coordinates obtained by the various software were independently used as initial values in a comparative adjustment made by scientific in-house software, which can apply constraints to evaluate the effectiveness of different methods of point extraction and accuracies on ground check points.

  13. Three Dimentional Reconstruction of Large Cultural Heritage Objects Based on Uav Video and Tls Data

    NASA Astrophysics Data System (ADS)

    Xu, Z.; Wu, T. H.; Shen, Y.; Wu, L.

    2016-06-01

    This paper investigates the synergetic use of unmanned aerial vehicle (UAV) and terrestrial laser scanner (TLS) in 3D reconstruction of cultural heritage objects. Rather than capturing still images, the UAV that equips a consumer digital camera is used to collect dynamic videos to overcome its limited endurance capacity. Then, a set of 3D point-cloud is generated from video image sequences using the automated structure-from-motion (SfM) and patch-based multi-view stereo (PMVS) methods. The TLS is used to collect the information that beyond the reachability of UAV imaging e.g., partial building facades. A coarse to fine method is introduced to integrate the two sets of point clouds UAV image-reconstruction and TLS scanning for completed 3D reconstruction. For increased reliability, a variant of ICP algorithm is introduced using local terrain invariant regions in the combined designation. The experimental study is conducted in the Tulou culture heritage building in Fujian province, China, which is focused on one of the TuLou clusters built several hundred years ago. Results show a digital 3D model of the Tulou cluster with complete coverage and textural information. This paper demonstrates the usability of the proposed method for efficient 3D reconstruction of heritage object based on UAV video and TLS data.

  14. Monitoring abandoned dreg fields of high-speed railway construction with UAV remote sensing technology

    NASA Astrophysics Data System (ADS)

    Lin, Jiayuan; Wang, Zhiliang; Wang, Yangchun; Lin, Yi; Du, Xiaolin

    2015-12-01

    High-speed railway construction will produce a large amount of abandoned dregs, so it is necessary to build enough dreg deposition fields along the railway. The task of the department of soil and water conservation is to monitor the construction and usage of abandoned dreg fields according to the design in the whole process of railway construction. As long linear construction projects, many high-speed railways go through regions of complex terrain, which poses great difficulties to monitoring current status of abandoned dreg fields. With the advantages of low cost, flexible launch and landing, safety, under-cloud-flying, hyperspatial image resolution, Unmanned Aerial Vehicles (UAVs) are very suitable for obtaining remote sensing imagery along the railway. One segment of the high-speed railway from Chongqing to Wanzhou and its neighborhood was chosen as the study area to demonstrate key technologies and specific procedures of monitoring abandoned dreg fields using the UAV system. The UAV system and its components are introduced along with the flight trajectories, acquired UAV imagery, and attitude data. Image preprocessing and generation of DEM and DOM are described in detail followed by image-based measurement accuracy assessment and abandoned dreg field status investigation on the resulting DOM and DEM. Results prove the feasibility and effectiveness of applying the fixed wing UAV system to rapidly monitoring the construction and usage of abandoned dreg fields

  15. Autonomous Airborne Refueling Demonstration Phase I Flight Test Results

    NASA Technical Reports Server (NTRS)

    Dibley, Ryan

    2007-01-01

    This viewgraph presentation provides flight test results of the automatic in-flight refueling of an Uninhabited Aerial Vehicle (UAV) using an automated hose-and-drogue refueling method. The program objective was to demonstrate one fully automatic engagement between the receiver and tanker aircraft. Systems involved, concept of operations, results and conclusions are included.

  16. A Collaborative Decision Environment for UAV Operations

    NASA Technical Reports Server (NTRS)

    D'Ortenzio, Matthew V.; Enomoto, Francis Y.; Johan, Sandra L.

    2005-01-01

    NASA is developing Intelligent Mission Management (IMM) technology for science missions employing long endurance unmanned aerial vehicles (UAV's). The IMM groundbased component is the Collaborative Decision Environment (CDE), a ground system that provides the Mission/Science team with situational awareness, collaboration, and decisionmaking tools. The CDE is used for pre-flight planning, mission monitoring, and visualization of acquired data. It integrates external data products used for planning and executing a mission, such as weather, satellite data products, and topographic maps by leveraging established and emerging Open Geospatial Consortium (OGC) standards to acquire external data products via the Internet, and an industry standard geographic information system (GIs) toolkit for visualization As a Science/Mission team may be geographically dispersed, the CDE is capable of providing access to remote users across wide area networks using Web Services technology. A prototype CDE is being developed for an instrument checkout flight on a manned aircraft in the fall of 2005, in preparation for a full deployment in support of the US Forest Service and NASA Ames Western States Fire Mission in 2006.

  17. Design of a synthetic vision overlay for UAV autoland monitoring

    NASA Astrophysics Data System (ADS)

    Tadema, Jochum; Theunissen, Eric

    2008-04-01

    For Unmanned Aerial Vehicles (UAVs), autonomous forms of autoland are being pursued that do not depend on special, deployability restraining, ground-based equipment for the generation of the reference path to the runway. Typically, these forms of autoland use runway location data from an onboard database to generate the reference path to the desired location. Synthetic Vision (SV) technology provides the opportunity to use conformally integrated guidance reference data to 'anchor' the goals of such an autoland system into the imagery of the nose-mounted camera. A potential use of this is to support the operator in determining whether the vehicle is flying towards the right location in the real world, e.g., the desired touchdown position on the runway. Standard conformally integrated symbology, representing e.g., the future pathway and runway boundaries, supports conformance monitoring and detection of latent positioning errors. Additional integration of landing performance criteria into the symbology supports assessment of the severity of these errors, further aiding the operator in the decision whether the automated landing should be allowed to continue or not. This paper presents the design and implementation of an SV overlay for UAV autoland procedures that is intended for conformance and integrity monitoring during final approach. It provides preview of mode changes and decision points and it supports the operator in assessing the integrity of the used guidance solution.

  18. Semi-autonomous UAV/UGV for dismounted urban operations

    NASA Astrophysics Data System (ADS)

    Trentini, Michael; Beckman, Blake

    2010-04-01

    Dismounted soldiers are clearly at the centre of modern asymmetric conflicts and unmanned systems of the future will play important roles in their support. Moreover, the nature of modern asymmetric conflicts requires dismounted soldiers to operate in urban environments with challenges of communication and limited situational awareness. To improve the situational awareness of dismounted soldiers in complex urban environments, Defence R&D Canada - Suffield (DRDC Suffield) envision Unmanned Air Vehicles (UAV) rotorcraft and Unmanned Ground Vehicles (UGV) cooperating in the battlespace. The capabilities provided to the UAV rotorcraft will include high speed maneuvers through urban terrain, overthe- horizon and loss of communications operations, and/or low altitude over-watch of dismounted units. This information is shared with both the dismounted soldiers and UGV. The man-sized, man-mobile UGV operates in close support to dismounted soldiers to provide a payload carrying capacity. Some of the possible payloads include chemical, biological, radiological and nuclear (CBRN) detection, intelligence, surveillance and reconnaissance (ISR), weapons, supplies, etc.. These unmanned systems are intended to increase situational awareness in urban environments and can be used to call upon nearby forces to react swiftly by providing acquired information to concentrate impact where required.

  19. Lidar on small UAV for 3D mapping

    NASA Astrophysics Data System (ADS)

    Tulldahl, H. Michael; Larsson, Hâkan

    2014-10-01

    Small UAV:s (Unmanned Aerial Vehicles) are currently in an explosive technical development phase. The performance of UAV-system components such as inertial navigation sensors, propulsion, control processors and algorithms are gradually improving. Simultaneously, lidar technologies are continuously developing in terms of reliability, accuracy, as well as speed of data collection, storage and processing. The lidar development towards miniature systems with high data rates has, together with recent UAV development, a great potential for new three dimensional (3D) mapping capabilities. Compared to lidar mapping from manned full-size aircraft a small unmanned aircraft can be cost efficient over small areas and more flexible for deployment. An advantage with high resolution lidar compared to 3D mapping from passive (multi angle) photogrammetry is the ability to penetrate through vegetation and detect partially obscured targets. Another advantage is the ability to obtain 3D data over the whole survey area, without the limited performance of passive photogrammetry in low contrast areas. The purpose of our work is to demonstrate 3D lidar mapping capability from a small multirotor UAV. We present the first experimental results and the mechanical and electrical integration of the Velodyne HDL-32E lidar on a six-rotor aircraft with a total weight of 7 kg. The rotating lidar is mounted at an angle of 20 degrees from the horizontal plane giving a vertical field-of-view of 10-50 degrees below the horizon in the aircraft forward directions. For absolute positioning of the 3D data, accurate positioning and orientation of the lidar sensor is of high importance. We evaluate the lidar data position accuracy both based on inertial navigation system (INS) data, and on INS data combined with lidar data. The INS sensors consist of accelerometers, gyroscopes, GPS, magnetometers, and a pressure sensor for altimetry. The lidar range resolution and accuracy is documented as well as the

  20. Automatic Isolation of Blurred Images from Uav Image Sequences

    NASA Astrophysics Data System (ADS)

    Sieberth, T.; Wackrow, R.; Chandler, J. H.

    2013-08-01

    Unmanned aerial vehicles (UAV) have become an interesting and active research topic for photogrammetry. Current research is based on images acquired by an UAV, which have a high ground resolution and good spectral and radiometrical resolution, due to the low flight altitudes combined with a high resolution camera. UAV image flights are also cost effective and have become attractive for many applications including change detection in small scale areas. One of the main problems preventing full automation of data processing of UAV imagery is the degradation effect of blur caused by camera movement during image acquisition. This can be caused by the normal flight movement of the UAV as well as strong winds, turbulence or sudden operator inputs. This blur disturbs the visual analysis and interpretation of the data, causes errors and can degrade the accuracy in automatic photogrammetric processing algorithms. The detection and removal of these images is currently achieved manually, which is both time consuming and prone to error, particularly for large image-sets. To increase the quality of data processing an automated filtering process is necessary, which must be both reliable and quick. This paper describes the development of an automatic filtering process, which is based upon the quantification of blur in an image. A "shaking table" was used to create images with known blur during a series of laboratory tests. This platform can be moved in one direction by a mathematical function controlled by a defined frequency and amplitude. The shaking table was used to displace a Nikon D80 digital SLR camera with a user defined frequency and amplitude. The actual camera displacement was measured accurately and exposures were synchronized, which provided the opportunity to acquire images with a known blur effect. Acquired images were processed digitally to determine a quantifiable measure of image blur, which has been created by the actual shaking table function. Once determined

  1. High Resolution UAV-based Passive Microwave L-band Imaging of Soil Moisture

    NASA Astrophysics Data System (ADS)

    Gasiewski, A. J.; Stachura, M.; Elston, J.; McIntyre, E. M.

    2013-12-01

    Due to long electrical wavelengths and aperture size limitations the scaling of passive microwave remote sensing of soil moisture from spaceborne low-resolution applications to high resolution applications suitable for precision agriculture requires use of low flying aerial vehicles. This presentation summarizes a project to develop a commercial Unmanned Aerial Vehicle (UAV) hosting a precision microwave radiometer for mapping of soil moisture in high-value shallow root-zone crops. The project is based on the use of the Tempest electric-powered UAV and a compact digital L-band (1400-1427 MHz) passive microwave radiometer developed specifically for extremely small and lightweight aerial platforms or man-portable, tractor, or tower-based applications. Notable in this combination are a highly integrated UAV/radiometer antenna design and use of both the upwelling emitted signal from the surface and downwelling cold space signal for precise calibration using a lobe-correlating radiometer architecture. The system achieves a spatial resolution comparable to the altitude of the UAV above the ground while referencing upwelling measurements to the constant and well-known background temperature of cold space. The radiometer incorporates digital sampling and radio frequency interference mitigation along with infrared, near-infrared, and visible (red) sensors for surface temperature and vegetation biomass correction. This NASA-sponsored project is being developed both for commercial application in cropland water management, L-band satellite validation, and estuarian plume studies.

  2. Unmanned Aerial Vehicle in Cadastral Applications

    NASA Astrophysics Data System (ADS)

    Manyoky, M.; Theiler, P.; Steudler, D.; Eisenbeiss, H.

    2011-09-01

    This paper presents the investigation of UAVs (Unmanned Aerial Vehicles) for use in cadastral surveying. Within the scope of a pilot study UAVs were tested for capturing geodata and compared with conventional data acquisition methods for cadastral surveying. Two study sites were therefore surveyed with a tachymeter-GNSS combination as well as a UAV system. The workflows of both methods were investigated and the resulting data were compared with the requirements of Swiss cadastral surveying. Concerning data acquisition and evaluation, the two systems are found to be comparable in terms of time expenditure, accuracy, and completeness. In conclusion, the UAV image orientation proved to be the limiting factor for the obtained accuracy due to the low- cost camera including camera calibration, image quality, and definition of the ground control points (natural or artificial). However, the required level of accuracy for cadastral surveying was reached. The advantage of UAV systems lies in their high flexibility and efficiency in capturing the surface of an area from a low flight altitude. In addition, further information such as orthoimages, elevation models and 3D objects can easily be gained from UAV images. Altogether, this project endorses the benefit of using UAVs in cadastral applications and the new opportunities they provide for cadastral surveying.

  3. An evaluation of a UAV guidance system with consumer grade GPS receivers

    NASA Astrophysics Data System (ADS)

    Rosenberg, Abigail Stella

    Remote sensing has been demonstrated an important tool in agricultural and natural resource management and research applications, however there are limitations that exist with traditional platforms (i.e., hand held sensors, linear moves, vehicle mounted, airplanes, remotely piloted vehicles (RPVs), unmanned aerial vehicles (UAVs) and satellites). Rapid technological advances in electronics, computers, software applications, and the aerospace industry have dramatically reduced the cost and increased the availability of remote sensing technologies. Remote sensing imagery vary in spectral, spatial, and temporal resolutions and are available from numerous providers. Appendix A presented results of a test project that acquired high-resolution aerial photography with a RPV to map the boundary of a 0.42 km2 fire area. The project mapped the boundaries of the fire area from a mosaic of the aerial images collected and compared this with ground-based measurements. The project achieved a 92.4% correlation between the aerial assessment and the ground truth data. Appendix B used multi-objective analysis to quantitatively assess the tradeoffs between different sensor platform attributes to identify the best overall technology. Experts were surveyed to identify the best overall technology at three different pixel sizes. Appendix C evaluated the positional accuracy of a relatively low cost UAV designed for high resolution remote sensing of small areas in order to determine the positional accuracy of sensor readings. The study evaluated the accuracy and uncertainty of a UAV flight route with respect to the programmed waypoints and of the UAV's GPS position, respectively. In addition, the potential displacement of sensor data was evaluated based on (1) GPS measurements on board the aircraft and (2) the autopilot's circuit board with 3-axis gyros and accelerometers (i.e., roll, pitch, and yaw). The accuracies were estimated based on a 95% confidence interval or similar methods. The

  4. Dual-Stack Single-Radio Communication Architecture for UAV Acting As a Mobile Node to Collect Data in WSNs.

    PubMed

    Sayyed, Ali; de Araújo, Gustavo Medeiros; Bodanese, João Paulo; Becker, Leandro Buss

    2015-09-16

    The use of mobile nodes to collect data in a Wireless Sensor Network (WSN) has gained special attention over the last years. Some researchers explore the use of Unmanned Aerial Vehicles (UAVs) as mobile node for such data-collection purposes. Analyzing these works, it is apparent that mobile nodes used in such scenarios are typically equipped with at least two different radio interfaces. The present work presents a Dual-Stack Single-Radio Communication Architecture (DSSRCA), which allows a UAV to communicate in a bidirectional manner with a WSN and a Sink node. The proposed architecture was specifically designed to support different network QoS requirements, such as best-effort and more reliable communications, attending both UAV-to-WSN and UAV-to-Sink communications needs. DSSRCA was implemented and tested on a real UAV, as detailed in this paper. This paper also includes a simulation analysis that addresses bandwidth consumption in an environmental monitoring application scenario. It includes an analysis of the data gathering rate that can be achieved considering different UAV flight speeds. Obtained results show the viability of using a single radio transmitter for collecting data from the WSN and forwarding such data to the Sink node.

  5. Dual-Stack Single-Radio Communication Architecture for UAV Acting As a Mobile Node to Collect Data in WSNs

    PubMed Central

    Sayyed, Ali; Medeiros de Araújo, Gustavo; Bodanese, João Paulo; Buss Becker, Leandro

    2015-01-01

    The use of mobile nodes to collect data in a Wireless Sensor Network (WSN) has gained special attention over the last years. Some researchers explore the use of Unmanned Aerial Vehicles (UAVs) as mobile node for such data-collection purposes. Analyzing these works, it is apparent that mobile nodes used in such scenarios are typically equipped with at least two different radio interfaces. The present work presents a Dual-Stack Single-Radio Communication Architecture (DSSRCA), which allows a UAV to communicate in a bidirectional manner with a WSN and a Sink node. The proposed architecture was specifically designed to support different network QoS requirements, such as best-effort and more reliable communications, attending both UAV-to-WSN and UAV-to-Sink communications needs. DSSRCA was implemented and tested on a real UAV, as detailed in this paper. This paper also includes a simulation analysis that addresses bandwidth consumption in an environmental monitoring application scenario. It includes an analysis of the data gathering rate that can be achieved considering different UAV flight speeds. Obtained results show the viability of using a single radio transmitter for collecting data from the WSN and forwarding such data to the Sink node. PMID:26389911

  6. AirSTAR: A UAV Platform for Flight Dynamics and Control System Testing

    NASA Technical Reports Server (NTRS)

    Jordan, Thomas L.; Foster, John V.; Bailey, Roger M.; Belcastro, Christine M.

    2006-01-01

    As part of the NASA Aviation Safety Program at Langley Research Center, a dynamically scaled unmanned aerial vehicle (UAV) and associated ground based control system are being developed to investigate dynamics modeling and control of large transport vehicles in upset conditions. The UAV is a 5.5% (seven foot wingspan), twin turbine, generic transport aircraft with a sophisticated instrumentation and telemetry package. A ground based, real-time control system is located inside an operations vehicle for the research pilot and associated support personnel. The telemetry system supports over 70 channels of data plus video for the downlink and 30 channels for the control uplink. Data rates are in excess of 200 Hz. Dynamic scaling of the UAV, which includes dimensional, weight, inertial, actuation, and control system scaling, is required so that the sub-scale vehicle will realistically simulate the flight characteristics of the full-scale aircraft. This testbed will be utilized to validate modeling methods, flight dynamics characteristics, and control system designs for large transport aircraft, with the end goal being the development of technologies to reduce the fatal accident rate due to loss-of-control.

  7. 3D Tree Dimensionality Assessment Using Photogrammetry and Small Unmanned Aerial Vehicles.

    PubMed

    Gatziolis, Demetrios; Lienard, Jean F; Vogs, Andre; Strigul, Nikolay S

    2015-01-01

    Detailed, precise, three-dimensional (3D) representations of individual trees are a prerequisite for an accurate assessment of tree competition, growth, and morphological plasticity. Until recently, our ability to measure the dimensionality, spatial arrangement, shape of trees, and shape of tree components with precision has been constrained by technological and logistical limitations and cost. Traditional methods of forest biometrics provide only partial measurements and are labor intensive. Active remote technologies such as LiDAR operated from airborne platforms provide only partial crown reconstructions. The use of terrestrial LiDAR is laborious, has portability limitations and high cost. In this work we capitalized on recent improvements in the capabilities and availability of small unmanned aerial vehicles (UAVs), light and inexpensive cameras, and developed an affordable method for obtaining precise and comprehensive 3D models of trees and small groups of trees. The method employs slow-moving UAVs that acquire images along predefined trajectories near and around targeted trees, and computer vision-based approaches that process the images to obtain detailed tree reconstructions. After we confirmed the potential of the methodology via simulation we evaluated several UAV platforms, strategies for image acquisition, and image processing algorithms. We present an original, step-by-step workflow which utilizes open source programs and original software. We anticipate that future development and applications of our method will improve our understanding of forest self-organization emerging from the competition among trees, and will lead to a refined generation of individual-tree-based forest models. PMID:26393926

  8. 3D Tree Dimensionality Assessment Using Photogrammetry and Small Unmanned Aerial Vehicles

    PubMed Central

    2015-01-01

    Detailed, precise, three-dimensional (3D) representations of individual trees are a prerequisite for an accurate assessment of tree competition, growth, and morphological plasticity. Until recently, our ability to measure the dimensionality, spatial arrangement, shape of trees, and shape of tree components with precision has been constrained by technological and logistical limitations and cost. Traditional methods of forest biometrics provide only partial measurements and are labor intensive. Active remote technologies such as LiDAR operated from airborne platforms provide only partial crown reconstructions. The use of terrestrial LiDAR is laborious, has portability limitations and high cost. In this work we capitalized on recent improvements in the capabilities and availability of small unmanned aerial vehicles (UAVs), light and inexpensive cameras, and developed an affordable method for obtaining precise and comprehensive 3D models of trees and small groups of trees. The method employs slow-moving UAVs that acquire images along predefined trajectories near and around targeted trees, and computer vision-based approaches that process the images to obtain detailed tree reconstructions. After we confirmed the potential of the methodology via simulation we evaluated several UAV platforms, strategies for image acquisition, and image processing algorithms. We present an original, step-by-step workflow which utilizes open source programs and original software. We anticipate that future development and applications of our method will improve our understanding of forest self-organization emerging from the competition among trees, and will lead to a refined generation of individual-tree-based forest models. PMID:26393926

  9. Unmanned aerial vehicles for rangeland mapping and monitoring: a comparison of two systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerial photography from unmanned aerial vehicles (UAVs) bridges the gap between ground-based observations and remotely sensed imagery from aerial and satellite platforms. UAVs can be deployed quickly and repeatedly, are less costly and safer than piloted aircraft, and can obtain very high-resolution...

  10. Unmanned aerial vehicle-based remote sensing for rangeland assessment, monitoring, and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rangeland comprises as much as 70% of the Earth’s land surface area. Much of this vast space is in very remote areas that are expensive and often impossible to access on the ground. Unmanned Aerial Vehicles (UAVs) have great potential for rangeland management. UAVs have several advantages over satel...

  11. Unmanned aerial vehicle: A unique platform for low-altitude remote sensing for crop management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unmanned aerial vehicles (UAV) provide a unique platform for remote sensing to monitor crop fields that complements remote sensing from satellite, aircraft and ground-based platforms. The UAV-based remote sensing is versatile at ultra-low altitude to be able to provide an ultra-high-resolution imag...

  12. UAV sensor and survivability issues

    SciTech Connect

    Canavan, G.H.

    1996-07-01

    This report discusses the most significant tradeoffs between the operating altitude and the complexity and cost of UAVs and sensors. Low altitudes allow less complex, smaller sensors and platforms, but are vulnerable to ground fire. High altitudes require more numerous and capable sensors, but provide wider swaths for more rapid coverage and reduced vulnerability to ground fire. It is shown that for mission requirements and air defenses that higher is not necessarily better and that optimal flight altitudes exist that can be determined analytically.

  13. Mission control of multiple unmanned aerial vehicles: a workload analysis.

    PubMed

    Dixon, Stephen R; Wickens, Christopher D; Chang, Dervon

    2005-01-01

    With unmanned aerial vehicles (UAVs), 36 licensed pilots flew both single-UAV and dual-UAV simulated military missions. Pilots were required to navigate each UAV through a series of mission legs in one of the following three conditions: a baseline condition, an auditory autoalert condition, and an autopilot condition. Pilots were responsible for (a) mission completion, (b) target search, and (c) systems monitoring. Results revealed that both the autoalert and the autopilot automation improved overall performance by reducing task interference and alleviating workload. The autoalert system benefited performance both in the automated task and mission completion task, whereas the autopilot system benefited performance in the automated task, the mission completion task, and the target search task. Practical implications for the study include the suggestion that reliable automation can help alleviate task interference and reduce workload, thereby allowing pilots to better handle concurrent tasks during single- and multiple-UAV flight control.

  14. Bio-inspired UAV routing, source localization, and acoustic signature classification for persistent surveillance

    NASA Astrophysics Data System (ADS)

    Burman, Jerry; Hespanha, Joao; Madhow, Upamanyu; Pham, Tien

    2011-06-01

    A team consisting of Teledyne Scientific Company, the University of California at Santa Barbara and the Army Research Laboratory* is developing technologies in support of automated data exfiltration from heterogeneous battlefield sensor networks to enhance situational awareness for dismounts and command echelons. Unmanned aerial vehicles (UAV) provide an effective means to autonomously collect data from a sparse network of unattended ground sensors (UGSs) that cannot communicate with each other. UAVs are used to reduce the system reaction time by generating autonomous collection routes that are data-driven. Bio-inspired techniques for search provide a novel strategy to detect, capture and fuse data. A fast and accurate method has been developed to localize an event by fusing data from a sparse number of UGSs. This technique uses a bio-inspired algorithm based on chemotaxis or the motion of bacteria seeking nutrients in their environment. A unique acoustic event classification algorithm was also developed based on using swarm optimization. Additional studies addressed the problem of routing multiple UAVs, optimally placing sensors in the field and locating the source of gunfire at helicopters. A field test was conducted in November of 2009 at Camp Roberts, CA. The field test results showed that a system controlled by bio-inspired software algorithms can autonomously detect and locate the source of an acoustic event with very high accuracy and visually verify the event. In nine independent test runs of a UAV, the system autonomously located the position of an explosion nine times with an average accuracy of 3 meters. The time required to perform source localization using the UAV was on the order of a few minutes based on UAV flight times. In June 2011, additional field tests of the system will be performed and will include multiple acoustic events, optimal sensor placement based on acoustic phenomenology and the use of the International Technology Alliance (ITA

  15. Deploying four optical UAV-based sensors over grassland: challenges and limitations

    NASA Astrophysics Data System (ADS)

    von Bueren, S. K.; Burkart, A.; Hueni, A.; Rascher, U.; Tuohy, M. P.; Yule, I. J.

    2015-01-01

    Unmanned aerial vehicles (UAVs) equipped with lightweight spectral sensors facilitate non-destructive, near-real-time vegetation analysis. In order to guarantee robust scientific analysis, data acquisition protocols and processing methodologies need to be developed and new sensors must be compared with state-of-the-art instruments. Four different types of optical UAV-based sensors (RGB camera, converted near-infrared camera, six-band multispectral camera and high spectral resolution spectrometer) were deployed and compared in order to evaluate their applicability for vegetation monitoring with a focus on precision agricultural applications. Data were collected in New Zealand over ryegrass pastures of various conditions and compared to ground spectral measurements. The UAV STS spectrometer and the multispectral camera MCA6 (Multiple Camera Array) were found to deliver spectral data that can match the spectral measurements of an ASD at ground level when compared over all waypoints (UAV STS: R2=0.98; MCA6: R2=0.92). Variability was highest in the near-infrared bands for both sensors while the band multispectral camera also overestimated the green peak reflectance. Reflectance factors derived from the RGB (R2=0.63) and converted near-infrared (R2=0.65) cameras resulted in lower accordance with reference measurements. The UAV spectrometer system is capable of providing narrow-band information for crop and pasture management. The six-band multispectral camera has the potential to be deployed to target specific broad wavebands if shortcomings in radiometric limitations can be addressed. Large-scale imaging of pasture variability can be achieved by either using a true colour or a modified near-infrared camera. Data quality from UAV-based sensors can only be assured, if field protocols are followed and environmental conditions allow for stable platform behaviour and illumination.

  16. Comparison of heat flux estimations from two turbulent exchange models based on thermal UAV data.

    NASA Astrophysics Data System (ADS)

    Hoffmann, Helene; Nieto, Hector; Jensen, Rasmus; Friborg, Thomas

    2015-04-01

    Advantages of UAV (Unmanned Aerial Vehicle) data-collection, compared to more traditional data-collections are numerous and already well-discussed (Berni et al., 2009; Laliberte et al., 2011; Turner et al., 2012). However studies investigating the quality and applications of UAV-data are crucial if advantages are to be beneficial for scientific purposes. In this study, thermal data collected over an agricultural site in Denmark have been obtained using a fixed-wing UAV and investigated for the estimation of heat fluxes. Estimation of heat fluxes requires high precision data and careful data processing. Latent, sensible and soil heat fluxes are estimates through two models of the two source energy modelling scheme driven by remotely sensed observations of land surface temperature; the original TSEB (Norman et al., 1995) and the DTD (Norman et al., 2000) which builds on the TSEB. The DTD model accounts for errors arising when deriving radiometric temperatures and can to some extent compensate for the fact that thermal cameras rarely are accurate. The DTD model requires an additional set of remotely sensed data during morning hours of the day at which heat fluxes are to be determined. This makes the DTD model ideal to use when combined with UAV data, because acquisition of data is not limited by fixed time by-passing tracks like satellite images (Guzinski et al., 2013). Based on these data, heat fluxes are computed from the two models and compared with fluxes from an eddy covariance station situated within the same designated agricultural site. This over-all procedure potentially enables an assessment of both the collected thermal UAV-data and of the two turbulent exchange models. Results reveal that both TSEB and DTD models compute heat fluxes from thermal UAV data that is within a very reasonable range and also that estimates from the DTD model is in best agreement with the eddy covariance system.

  17. Best practice for minimising unmanned aerial vehicle disturbance to wildlife in biological field research.

    PubMed

    Hodgson, Jarrod C; Koh, Lian Pin

    2016-05-23

    The use of unmanned aerial vehicles (UAVs), colloquially referred to as 'drones', for biological field research is increasing [1-3]. Small, civilian UAVs are providing a viable, economical tool for ecology researchers and environmental managers. UAVs are particularly useful for wildlife observation and monitoring as they can produce systematic data of high spatial and temporal resolution [4]. However, this new technology could also have undesirable and unforeseen impacts on wildlife, the risks of which we currently have little understanding [5-7]. There is a need for a code of best practice in the use of UAVs to mitigate or alleviate these risks, which we begin to develop here.

  18. Modeling and optimization of multiple unmanned aerial vehicles system architecture alternatives.

    PubMed

    Qin, Dongliang; Li, Zhifei; Yang, Feng; Wang, Weiping; He, Lei

    2014-01-01

    Unmanned aerial vehicle (UAV) systems have already been used in civilian activities, although very limitedly. Confronted different types of tasks, multi UAVs usually need to be coordinated. This can be extracted as a multi UAVs system architecture problem. Based on the general system architecture problem, a specific description of the multi UAVs system architecture problem is presented. Then the corresponding optimization problem and an efficient genetic algorithm with a refined crossover operator (GA-RX) is proposed to accomplish the architecting process iteratively in the rest of this paper. The availability and effectiveness of overall method is validated using 2 simulations based on 2 different scenarios.

  19. Modeling and Optimization of Multiple Unmanned Aerial Vehicles System Architecture Alternatives

    PubMed Central

    Wang, Weiping; He, Lei

    2014-01-01

    Unmanned aerial vehicle (UAV) systems have already been used in civilian activities, although very limitedly. Confronted different types of tasks, multi UAVs usually need to be coordinated. This can be extracted as a multi UAVs system architecture problem. Based on the general system architecture problem, a specific description of the multi UAVs system architecture problem is presented. Then the corresponding optimization problem and an efficient genetic algorithm with a refined crossover operator (GA-RX) is proposed to accomplish the architecting process iteratively in the rest of this paper. The availability and effectiveness of overall method is validated using 2 simulations based on 2 different scenarios. PMID:25140328

  20. Best practice for minimising unmanned aerial vehicle disturbance to wildlife in biological field research.

    PubMed

    Hodgson, Jarrod C; Koh, Lian Pin

    2016-05-23

    The use of unmanned aerial vehicles (UAVs), colloquially referred to as 'drones', for biological field research is increasing [1-3]. Small, civilian UAVs are providing a viable, economical tool for ecology researchers and environmental managers. UAVs are particularly useful for wildlife observation and monitoring as they can produce systematic data of high spatial and temporal resolution [4]. However, this new technology could also have undesirable and unforeseen impacts on wildlife, the risks of which we currently have little understanding [5-7]. There is a need for a code of best practice in the use of UAVs to mitigate or alleviate these risks, which we begin to develop here. PMID:27218843

  1. Isotopic CO2 Instrumentation for UAV Measurements

    NASA Astrophysics Data System (ADS)

    Gomez, A.; Silver, J.

    2013-12-01

    Carbon dioxide is the largest component of anthroprogenic green house gas emissions. Knowing atmospheric 13CO2/12CO2 ratios precisely is important for understanding biogenic and anthroprogenic sources and sinks for carbon. Instrumentation mounted on UAV aircraft would enable important spatial isotopic CO2 information. However, current isotopic CO2 instrumentation have unfavorable attributes for UAV use, such as high power requirements, high cost, high weight, and large size. Here we present the early development of a compact isotopic CO2 instrument that is designed to nullify effects of pressure, temperature and moisture, and will ultimately be suitable for UAV deployment.

  2. Landing spot selection for UAV emergency landing

    NASA Astrophysics Data System (ADS)

    Eendebak, P. T.; van Eekeren, A. W. M.; den Hollander, R. J. M.

    2013-05-01

    We present a robust method for landing zone selection using obstacle detection to be used for UAV emergency landings. The method is simple enough to allow real-time implementation on a UAV system. The method is able to detect objects in the presence of camera movement and motion parallax. Using the detected obstacles we select a safe landing zone for the UAV. The motion and structure detection uses background estimation of stabilized video. The background variation is measured and used to enhance the moving objects if necessary. In the motion and structure map a distance transform is calculated to find a suitable location for landing.

  3. Demonstrations of bio-inspired perching landing gear for UAVs

    NASA Astrophysics Data System (ADS)

    Tieu, Mindy; Michael, Duncan M.; Pflueger, Jeffery B.; Sethi, Manik S.; Shimazu, Kelli N.; Anthony, Tatiana M.; Lee, Christopher L.

    2016-04-01

    Results are presented which demonstrate the feasibility and performance of two concepts of biologically-inspired landing-gear systems that enable bird-sized, unmanned aerial vehicles (UAV's) to land, perch, and take-off from branchlike structures and/or ledges. The first concept follows the anatomy of birds that can grasp ahold of a branch and perch as tendons in their legs are tensioned. This design involves a gravity-activated, cable-driven, underactuated, graspingfoot mechanism. As the UAV lands, its weight collapses a four-bar linkage pulling a cable which curls two opposing, multi-segmented feet to grasp the landing target. Each foot is a single, compliant mechanism fabricated by simultaneouly 3D-printing a flexible thermo-plastic and a stiffer ABS plastic. The design is optimized to grasp structures over a range of shapes and sizes. Quasi-static and flight tests of this landing gear affixed to RC rotorcraft (24 cm to 550 cm in diameter) demonstrate that the aircraft can land, perch, and take-off from a tree branch, rectangular wood board, PVC pipe, metal hand rail, chair armrest, and in addition, a stone wall ledge. Stability tests show that perching is maintained under base and wind disturbances. The second design concept, inspired by roosting bats, is a two-material, 3D-printed hooking mechanism that enables the UAV to stably suspend itself from a wire or small-diameter branch. The design balances structural stiffness for support and flexibility for the perching process. A flight-test demonstrates the attaching and dis-engaging of a small, RC quadcopter from a suspended line.

  4. Development of a Low-Cost UAV Doppler Radar Data System

    NASA Technical Reports Server (NTRS)

    Knuble, Joseph; Li, Lihua; Heymsfield, Gerry

    2005-01-01

    A viewgraph presentation on the design of a low cost unmanned aerial vehicle (UAV) doppler radar data system is presented. The topics include: 1) Science and Mission Background; 2) Radar Requirements and Specs; 3) Radar Realization: RF System; 4) Processing of RF Signal; 5) Data System Design Process; 6) Can We Remove the DSP? 7) Determining Approximate Speed Requirements; 8) Radar Realization: Data System; 9) Data System Operation; and 10) Results.

  5. UAVSAR: A New NASA Airborne SAR System for Science and Technology Research

    NASA Technical Reports Server (NTRS)

    Rosen, Paul A.; Hensley, Scott; Wheeler, Kevin; Sadowy, Greg; Miller, Tim; Shaffer, Scott; Muellerschoen, Ron; Jones, Cathleen; Zebker, Howard; Madsen, Soren

    2006-01-01

    NASA's Jet Propulsion Laboratory is currently building a reconfigurable, polarimetric L-band synthetic aperture radar (SAR), specifically designed to acquire airborne repeat track SAR data for differential interferometric measurements. Differentian interferometry can provide key deformation measurements, important for studies of earthquakes, volcanoes and other dynamically changing phenomena. Using precision real-time GPS and a sensor controlled flight management system, the system will be able to fly predefined paths with great precision. The expected performance of the flight control system will constrain the flight path to be within a 10 m diameter tube about the desired flight track. The radar will be designed to be operable on a UAV (Unpiloted Aria1 Vehicle) but will initially be demonstrated on a NASA Gulfstream III. The radar will be fully polarimetric, with a range bandwidth of 80 MHz (2 m range resolution), and will support a 16 km range swath. The antenna will be electronically steered along track to assure that the antenna beam can be directed independently, regardless of the wind direction and speed. Other features supported by the antenna include elevation monopulse and pulse-to-pulse re-steering capabilities that will enable some novel modes of operation. The system will nominally operate at 45,000 ft (13800 m). The program began as an Instrument Incubator Project (IIP) funded by NASA Earth Science and Technology Office (ESTO).

  6. Feasibility Study for an Autonomous UAV -Magnetometer System -- Final Report on SERDP SEED 1509:2206

    SciTech Connect

    Roelof Versteeg; Mark McKay; Matt Anderson; Ross Johnson; Bob Selfridge; Jay Bennett

    2007-09-01

    Large areas across the United States are potentially contaminated with UXO, with some ranges encompassing tens to hundreds of thousands of acres. Technologies are needed which will allow for cost effective wide area scanning with 1) near 100 % coverage and 2) near 100 % detection of subsurface ordnance or features indicative of subsurface ordnance. The current approach to wide area scanning is a multi-level one, in which medium altitude fixed wing optical imaging is used for an initial site assessment. This assessment is followed with low altitude manned helicopter based magnetometry followed by surface investigations using either towed geophysical sensor arrays or man portable sensors. In order to be effective for small UXO detection, the sensing altitude for magnetic site investigations needs to be on the order of 1 – 3 meters. These altitude requirements means that manned helicopter surveys will generally only be feasible in large, open and relatively flat terrains. While such surveys are effective in mapping large areas relatively fast there are substantial mobilization/demobilization, staffing and equipment costs associated with these surveys (resulting in costs of approximately $100-$150/acre). Surface towed arrays provide high resolution maps but have other limitations, e.g. in their ability to navigate rough terrain effectively. Thus, other systems are needed allowing for effective data collection. An UAV (Unmanned Aerial Vehicle) magnetometer platform is an obvious alternative. The motivation behind such a system is that it would be safer for the operators, cheaper in initial and O&M costs, and more effective in terms of site characterization. However, while UAV data acquisition from fixed wing platforms for large (> 200 feet) stand off distances is relatively straight forward, a host of challenges exist for low stand-off distance (~ 6 feet) UAV geophysical data acquisition. The objective of SERDP SEED 1509:2006 was to identify the primary challenges

  7. Estimating evaporation with thermal UAV data and two-source energy balance models

    NASA Astrophysics Data System (ADS)

    Hoffmann, H.; Nieto, H.; Jensen, R.; Guzinski, R.; Zarco-Tejada, P.; Friborg, T.

    2016-02-01

    Estimating evaporation is important when managing water resources and cultivating crops. Evaporation can be estimated using land surface heat flux models and remotely sensed land surface temperatures (LST), which have recently become obtainable in very high resolution using lightweight thermal cameras and Unmanned Aerial Vehicles (UAVs). In this study a thermal camera was mounted on a UAV and applied into the field of heat fluxes and hydrology by concatenating thermal images into mosaics of LST and using these as input for the two-source energy balance (TSEB) modelling scheme. Thermal images are obtained with a fixed-wing UAV overflying a barley field in western Denmark during the growing season of 2014 and a spatial resolution of 0.20 m is obtained in final LST mosaics. Two models are used: the original TSEB model (TSEB-PT) and a dual-temperature-difference (DTD) model. In contrast to the TSEB-PT model, the DTD model accounts for the bias that is likely present in remotely sensed LST. TSEB-PT and DTD have already been well tested, however only during sunny weather conditions and with satellite images serving as thermal input. The aim of this study is to assess whether a lightweight thermal camera mounted on a UAV is able to provide data of sufficient quality to constitute as model input and thus attain accurate and high spatial and temporal resolution surface energy heat fluxes, with special focus on latent heat flux (evaporation). Furthermore, this study evaluates the performance of the TSEB scheme during cloudy and overcast weather conditions, which is feasible due to the low data retrieval altitude (due to low UAV flying altitude) compared to satellite thermal data that are only available during clear-sky conditions. TSEB-PT and DTD fluxes are compared and validated against eddy covariance measurements and the comparison shows that both TSEB-PT and DTD simulations are in good agreement with eddy covariance measurements, with DTD obtaining the best results. The

  8. Analysis of motor vehicle emissions over eastern Los Angeles, California from in-situ airborne measurements of trace gases and particulates during CalNex

    NASA Astrophysics Data System (ADS)

    Pollack, I. B.; Ryerson, T. B.; Trainer, M.; Frost, G. J.; Holloway, J. S.; McKeen, S. A.; Peischl, J.; Fahey, D. W.; Perring, A.; Schwarz, J. P.; Spackman, J. R.

    2010-12-01

    In-situ measurements of trace gases and particulates were acquired on the instrumented NOAA WP-3D aircraft during the CalNex (California Research at the Nexus of Air Quality and Climate Change) field study in May and June 2010. Multiple daytime research flights under similar meteorological conditions provide a sufficient data set for characterizing automobile emissions over the eastern Los Angeles (eLA) area of the South Coast air basin. Ratios of nitrogen oxides (NOx) and black carbon (BC) to carbon monoxide (CO) are used to isolate emissions of light duty vehicles from those of medium/heavy duty diesel trucks. Observations in the mixed boundary layer for the eLA area are separated according to latitude, longitude, and altitude. Industrial influences are eliminated by filtering the data according to SO2 mixing ratio and wind direction. The resulting correlations show weekday-to-weekend differences in enhancement ratios of NOx to CO and BC to CO, indicating a general tendency for higher emissions from heavy duty vehicles during the week. The CalNex data over eLA in 2010 will be compared to eLA data from a research flight in May 2002 by the WP-3D aircraft during the Intercontinental Transport and Chemical Transformation (ITCT) field study.

  9. Airborne Emissions from 1961 to 2004 of Benzo[a]pyrene from U.S. Vehicles per km of Travel Based on Tunnel Studies

    PubMed Central

    2008-01-01

    We identified 13 historical measurements of polycyclic aromatic hydrocarbons (PAHs) in U.S. vehicular traffic tunnels that were either directly presented as tailpipe emission factors in μg per vehicle-kilometer or convertible to such a form. Tunnel measurements capture fleet cruise emissions. Emission factors for benzo[a]pyrene (BaP) for a tunnel fleet operating under cruise conditions were highest prior to the 1980s and fell from more than 30-μg per vehicle-km to approximately 2-μg/km in the 1990s, an approximately 15-fold decline. Total annual U.S. (cruise) emissions of BaP dropped by a lesser factor, because total annual km driven increased by a factor of 2.7 during the period. Other PAH compounds measured in tunnels over the 40-year period (e.g., benzo[ghi]perylene, coronene) showed comparable reduction factors in emissions. PAH declines were comparable to those measured in tunnels for carbon monoxide, volatile organic compounds, and particulate organic carbon. The historical PAH “source terms” determined from the data are relevant to quantifying the benefits of emissions control technology and can be used in epidemiological studies evaluating the health effects of exposure, such as those undertaken with breast cancer in New York State. PMID:18939564

  10. Synthesis of the unmanned aerial vehicle remote control augmentation system

    NASA Astrophysics Data System (ADS)

    Tomczyk, Andrzej

    2014-12-01

    Medium size Unmanned Aerial Vehicle (UAV) usually flies as an autonomous aircraft including automatic take-off and landing phases. However in the case of the on-board control system failure, the remote steering is using as an emergency procedure. In this reason, remote manual control of unmanned aerial vehicle is used more often during take-of and landing phases. Depends on UAV take-off mass and speed (total energy) the potential crash can be very danger for airplane and environment. So, handling qualities of UAV is important from pilot-operator point of view. In many cases the dynamic properties of remote controlling UAV are not suitable for obtaining the desired properties of the handling qualities. In this case the control augmentation system (CAS) should be applied. Because the potential failure of the on-board control system, the better solution is that the CAS algorithms are placed on the ground station computers. The method of UAV handling qualities shaping in the case of basic control system failure is presented in this paper. The main idea of this method is that UAV reaction on the operator steering signals should be similar - almost the same - as reaction of the "ideal" remote control aircraft. The model following method was used for controller parameters calculations. The numerical example concerns the medium size MP-02A UAV applied as an aerial observer system.

  11. Synthesis of the unmanned aerial vehicle remote control augmentation system

    SciTech Connect

    Tomczyk, Andrzej

    2014-12-10

    Medium size Unmanned Aerial Vehicle (UAV) usually flies as an autonomous aircraft including automatic take-off and landing phases. However in the case of the on-board control system failure, the remote steering is using as an emergency procedure. In this reason, remote manual control of unmanned aerial vehicle is used more often during take-of and landing phases. Depends on UAV take-off mass and speed (total energy) the potential crash can be very danger for airplane and environment. So, handling qualities of UAV is important from pilot-operator point of view. In many cases the dynamic properties of remote controlling UAV are not suitable for obtaining the desired properties of the handling qualities. In this case the control augmentation system (CAS) should be applied. Because the potential failure of the on-board control system, the better solution is that the CAS algorithms are placed on the ground station computers. The method of UAV handling qualities shaping in the case of basic control system failure is presented in this paper. The main idea of this method is that UAV reaction on the operator steering signals should be similar - almost the same - as reaction of the 'ideal' remote control aircraft. The model following method was used for controller parameters calculations. The numerical example concerns the medium size MP-02A UAV applied as an aerial observer system.

  12. Accuracy Assessment of a Uav-Based Landslide Monitoring System

    NASA Astrophysics Data System (ADS)

    Peppa, M. V.; Mills, J. P.; Moore, P.; Miller, P. E.; Chambers, J. E.

    2016-06-01

    Landslides are hazardous events with often disastrous consequences. Monitoring landslides with observations of high spatio-temporal resolution can help mitigate such hazards. Mini unmanned aerial vehicles (UAVs) complemented by structure-from-motion (SfM) photogrammetry and modern per-pixel image matching algorithms can deliver a time-series of landslide elevation models in an automated and inexpensive way. This research investigates the potential of a mini UAV, equipped with a Panasonic Lumix DMC-LX5 compact camera, to provide surface deformations at acceptable levels of accuracy for landslide assessment. The study adopts a self-calibrating bundle adjustment-SfM pipeline using ground control points (GCPs). It evaluates misalignment biases and unresolved systematic errors that are transferred through the SfM process into the derived elevation models. To cross-validate the research outputs, results are compared to benchmark observations obtained by standard surveying techniques. The data is collected with 6 cm ground sample distance (GSD) and is shown to achieve planimetric and vertical accuracy of a few centimetres at independent check points (ICPs). The co-registration error of the generated elevation models is also examined in areas of stable terrain. Through this error assessment, the study estimates that the vertical sensitivity to real terrain change of the tested landslide is equal to 9 cm.

  13. UAV-based photogrammetry: monitoring of a building zone

    NASA Astrophysics Data System (ADS)

    Unger, J.; Reich, M.; Heipke, C.

    2014-06-01

    The use of small-size unmanned aerial vehicles (UAV) for civil applications in many different fields such as archaeology, disaster monitoring, aerial surveying or mapping has significantly increased in recent years. The high flexibility and the low cost per acquired information compared to classical systems - terrestrial or aerial - offer a high variety of different applications. This paper addresses the photogrammetric analysis of a monitoring project and gives an insight into the potential of UAV using low cost sensors and present-day processing software. The area of interest is the "zero:e-park", a building zone of zero emission housing in Hannover, Germany, that we monitored in three different epochs over a period of five months. We show that we can derive three dimensional information with an accuracy of a few centimetres. Changes during the epochs, also small ones like the dismantling of scaffolding can be detected. We also depict the limitations of the DEM generation approach which occur at sharp edges and height jumps as well as repetitive structure. Additionally, we compare two different commercial software packages which reveals that some systematic errors still remain in the results.

  14. Confidence metrics analysis of a fixed-wing UAV

    NASA Astrophysics Data System (ADS)

    Polgar, Janos

    Uninhabited aerial vehicles (UAVs) are becoming popular in the development process of full scale aircrafts and as research platforms. Due to their complexity they provide development and test environments for a wide range of applications. Supporting research projects in safety critical systems, classes, the University of Minnesota Department of Aerospace Engineering and Mechanics have been developing a low-cost UAV research facility. This facility includes models of a family of fixed wing airframes, controllers, a diverse set of guidance algorithms. A flight software is written which implements an autopilot system, including the aforementioned algorithms, and provides datalogging. The software package is equipped with tools to evaluate flight test results. The model of any plant is never 100% accurate. There are always differences between the real system and the dynamical model of it. Uncertainties can be introduced into the model, which are trying to capture uncertainty in model parameters and unmodeled dynamics. Even though the aircraft model in the package is fairly accurate, it is interesting to investigate 'how good' the model is, i.e. how robust the model in the closed loop is against uncertainties. Earlier work in this project mainly focused on plant modeling and controller design. Extensive controller analysis, however, has not performed yet, what motivates the work behind this thesis.

  15. Application of UAVs at the Savannah River Site

    SciTech Connect

    Hofstetter, K.J.; Pendergast, M.M.

    1996-08-01

    Small, unmanned aerial vehicles (UAVs) equipped with sensors for physical, chemical, and radiochemical measurements of remote environments have been tested at the Savannah River Site (SRS). A miniature helicopter was used as an aerial platform for testing a variety of sensors with outputs integrated with the flight control system for real-time data acquisition and evaluation. The sensors included a precision magnetometer, two broad band infra-red radiometers, a 1-inch by 1-inch Nal(TI) scintillation detector, and an on-board color video camera. Included in the avionics package was an ultrasonic altimeter, a precision barometer, and a portable Global Positioning System. Two separate demonstration locations at SRS were flown that had been previously characterized by careful sampling and analyses and by aerial surveys at high altitudes. The Steed Pond demonstration site contains elevated levels of uranium in the soil and pond silt due to runoff from one of the site`s uranium fuel and target production areas. The soil at the other site is contaminated with oil bearing materials and contains some buried objects. The results and limitations of the UAV surveys are presented and improvements for future measurements are discussed.

  16. Performance Characteristic Mems-Based IMUs for UAVs Navigation

    NASA Astrophysics Data System (ADS)

    Mohamed, H. A.; Hansen, J. M.; Elhabiby, M. M.; El-Sheimy, N.; Sesay, A. B.

    2015-08-01

    Accurate 3D reconstruction has become essential for non-traditional mapping applications such as urban planning, mining industry, environmental monitoring, navigation, surveillance, pipeline inspection, infrastructure monitoring, landslide hazard analysis, indoor localization, and military simulation. The needs of these applications cannot be satisfied by traditional mapping, which is based on dedicated data acquisition systems designed for mapping purposes. Recent advances in hardware and software development have made it possible to conduct accurate 3D mapping without using costly and high-end data acquisition systems. Low-cost digital cameras, laser scanners, and navigation systems can provide accurate mapping if they are properly integrated at the hardware and software levels. Unmanned Aerial Vehicles (UAVs) are emerging as a mobile mapping platform that can provide additional economical and practical advantages. However, such economical and practical requirements need navigation systems that can provide uninterrupted navigation solution. Hence, testing the performance characteristics of Micro-Electro-Mechanical Systems (MEMS) or low cost navigation sensors for various UAV applications is important research. This work focuses on studying the performance characteristics under different manoeuvres using inertial measurements integrated with single point positioning, Real-Time-Kinematic (RTK), and additional navigational aiding sensors. Furthermore, the performance of the inertial sensors is tested during Global Positioning System (GPS) signal outage.

  17. Assessing UAV platform types and optical sensor specifications

    NASA Astrophysics Data System (ADS)

    Altena, B.; Goedemé, T.

    2014-05-01

    Photogrammetric acquisition with unmanned aerial vehicles (UAV) has grown extensively over the last couple of years. Such mobile platforms and their processing software have matured, resulting in a market which offers off-the-shelf mapping solutions to surveying companies and geospatial enterprises. Different approaches in platform type and optical instruments exist, though its resulting products have similar specifications. To demonstrate differences in acquisitioning practice, a case study over an open mine was flown with two different off-the-shelf UAVs (a fixed-wing and a multi-rotor). The resulting imagery is analyzed to clarify the differences in collection quality. We look at image settings, and stress the fact of photographic experience if manual setting are applied. For mapping production it might be safest to set the camera on automatic. Furthermore, we try to estimate if blur is present due to image motion. A subtle trend seems to be present, for the fast flying platform though its extent is of similar order to the slow moving one. It shows both systems operate at their limits. Finally, the lens distortion is assessed with special attention to chromatic aberration. Here we see that through calibration such aberrations could be present, however detecting this phenomena directly on imagery is not straightforward. For such effects a normal lens is sufficient, though a better lens and collimator does give significant improvement.

  18. On Fundamental Evaluation Using Uav Imagery and 3d Modeling Software

    NASA Astrophysics Data System (ADS)

    Nakano, K.; Suzuki, H.; Tamino, T.; Chikatsu, H.

    2016-06-01

    Unmanned aerial vehicles (UAVs), which have been widely used in recent years, can acquire high-resolution images with resolutions in millimeters; such images cannot be acquired with manned aircrafts. Moreover, it has become possible to obtain a surface reconstruction of a realistic 3D model using high-overlap images and 3D modeling software such as Context capture, Pix4Dmapper, Photoscan based on computer vision technology such as structure from motion and multi-view stereo. 3D modeling software has many applications. However, most of them seem to not have obtained appropriate accuracy control in accordance with the knowledge of photogrammetry and/or computer vision. Therefore, we performed flight tests in a test field using an UAV equipped with a gimbal stabilizer and consumer grade digital camera. Our UAV is a hexacopter and can fly according to the waypoints for autonomous flight and can record flight logs. We acquired images from different altitudes such as 10 m, 20 m, and 30 m. We obtained 3D reconstruction results of orthoimages, point clouds, and textured TIN models for accuracy evaluation in some cases with different image scale conditions using 3D modeling software. Moreover, the accuracy aspect was evaluated for different units of input image—course unit and flight unit. This paper describes the fundamental accuracy evaluation for 3D modeling using UAV imagery and 3D modeling software from the viewpoint of close-range photogrammetry.

  19. Hierarchical heuristic search using a Gaussian mixture model for UAV coverage planning.

    PubMed

    Lin, Lanny; Goodrich, Michael A

    2014-12-01

    During unmanned aerial vehicle (UAV) search missions, efficient use of UAV flight time requires flight paths that maximize the probability of finding the desired subject. The probability of detecting the desired subject based on UAV sensor information can vary in different search areas due to environment elements like varying vegetation density or lighting conditions, making it likely that the UAV can only partially detect the subject. This adds another dimension of complexity to the already difficult (NP-Hard) problem of finding an optimal search path. We present a new class of algorithms that account for partial detection in the form of a task difficulty map and produce paths that approximate the payoff of optimal solutions. The algorithms use the mode goodness ratio heuristic that uses a Gaussian mixture model to prioritize search subregions. The algorithms search for effective paths through the parameter space at different levels of resolution. We compare the performance of the new algorithms against two published algorithms (Bourgault's algorithm and LHC-GW-CONV algorithm) in simulated searches with three real search and rescue scenarios, and show that the new algorithms outperform existing algorithms significantly and can yield efficient paths that yield payoffs near the optimal.

  20. Preliminary gully assessment using photo-reconstruction from own-manufactured UAV images

    NASA Astrophysics Data System (ADS)

    Ruano-Castro, Vicente; Castillo, Carlos; Gomez, Jose A.; Perez, Rafael

    2014-05-01

    Unmanned Aerial Vehicles (UAV) are becoming increasingly useful in several professional and research fields, among other, in geomorphology applications. UAV helicopters (with one or more rotors) present some advantages compared to fixed wing drones such as the possibility of stationary fly. On the other hand, 3D-photoreconstruction has been successfully applied for gully assessment at the reach scale. The combination of both approaches can result in a substantial reduction of time requirements at the gully network scale. The purpose of this communication is to describe the construction of an UAV with carbor-fiber frame and its fitting for capturing air images. Routes controlled by GPS were programmed in advance using Google Earth. Although an improved design with 8 rotors is in progress, currently the design is equipped with 4 rotors. This new design will allow the use of heavier and more precise cameras. In addition, the isolation of the inner electronic equipment will increase the possibility of use in bad weather. The images obtained by the UAV were processed using 3D-photoreconstruction to derive a digital elevation model of a several-hundred meters gully. References Castillo, C., R. Perez, M.R. James, J.N. Quinton, E.V. Taguas, J.A. Gómez. 2012. Comparing the Accuracy of Several Field Methods for Measuring Gully Erosion. Soil Science Society of America Journal 76: 1319-1332.

  1. Using UAVs and digital image processing to quantify areas of soil and vegetation

    NASA Astrophysics Data System (ADS)

    Chaves, A. A.; La Scalea, R. A.; Colturato, A. B.; Kawabata, C. L. O.; Furtado, E. L.; Castelo Branco, K. R. L. J.

    2015-09-01

    Unmanned aerial vehicles (UAVs) are becoming a very popular tool for remote sensing and crop monitoring. They are more easily deployed, cheaper and can obtain images with higher spatial-resolution than satellites. Some small, commercial UAVs can obtain images with spatial-resolution as low as 1.5cm per pixel. This opens up the range of possible remote sensing and monitoring applications. Moreover, they can cover large areas in very little time, such as 50 ha in about 20min, which makes UAVs the ideal tool for monitoring large farms and plantations. On the other hand, it is important to know precisely the area covered by farms in order to avoid invasion of other properties or preserved areas, and also to detect flaws in the plantation area. However, it is difficult to measure planted areas in some cases, such as Eucalyptus crops. Therefore, this paper aims to evaluate the use of UAV imagery for precise area measurement in Eucalyptus crops. We developed an image-processing algorithm to segment regions of soil, low biomass and high biomass and tested it on a Eucalyptus plantation in the city of Lenis Paulista -SP, Brazil. Results show that the area quantification is very accurate especially for bare soil regions and this method can be used to estimate areas in other scenarios.

  2. Multi- and hyperspectral UAV imaging system for forest and agriculture applications

    NASA Astrophysics Data System (ADS)

    Mäkynen, Jussi; Saari, Heikki; Holmlund, Christer; Mannila, Rami; Antila, Tapani

    2012-06-01

    VTT Technical Research Centre of Finland has developed a Fabry-Perot Interferometer (FPI) based hyperspectral imager compatible with light weight UAV (Unmanned Aerial Vehicle) platforms (SPIE Proc. 74741, 8186B2). The FPI based hyperspectral imager was used in a UAV imaging campaign for forest and agriculture tests during the summer 2011 (SPIE Proc. 81743). During these tests high spatial resolution Color-Infrared (CIR) images and hyperspectral images were recorded on separate flights. The spectral bands of the CIR camera were 500 - 580 nm for the green band, 580 - 700 nm for the red band and 700 - 1000 nm for the near infrared band. For the summer 2012 flight campaign a new hyperspectral imager is currently being developed. A custom made CIR camera will also be used. The system which includes both the high spatial resolution Color-Infrared camera and a light weight hyperspectral imager can provide all necessary data with just one UAV flight over the target area. The new UAV imaging system contains a 4 Megapixel CIR camera which is used for the generation of the digital surface models and CIR mosaics. The hyperspectral data can be recorded in the wavelength range 500 - 900 nm at a resolution of 10 - 30 nm at FWHM. The resolution can be selected from approximate values of 10, 15, 20 or 30 nm at FWHM.

  3. New generation of human machine interfaces for controlling UAV through depth-based gesture recognition

    NASA Astrophysics Data System (ADS)

    Mantecón, Tomás.; del Blanco, Carlos Roberto; Jaureguizar, Fernando; García, Narciso

    2014-06-01

    New forms of natural interactions between human operators and UAVs (Unmanned Aerial Vehicle) are demanded by the military industry to achieve a better balance of the UAV control and the burden of the human operator. In this work, a human machine interface (HMI) based on a novel gesture recognition system using depth imagery is proposed for the control of UAVs. Hand gesture recognition based on depth imagery is a promising approach for HMIs because it is more intuitive, natural, and non-intrusive than other alternatives using complex controllers. The proposed system is based on a Support Vector Machine (SVM) classifier that uses spatio-temporal depth descriptors as input features. The designed descriptor is based on a variation of the Local Binary Pattern (LBP) technique to efficiently work with depth video sequences. Other major consideration is the especial hand sign language used for the UAV control. A tradeoff between the use of natural hand signs and the minimization of the inter-sign interference has been established. Promising results have been achieved in a depth based database of hand gestures especially developed for the validation of the proposed system.

  4. Evolutionary algorithm based offline/online path planner for UAV navigation.

    PubMed

    Nikolos, I K; Valavanis, K P; Tsourveloudis, N C; Kostaras, A N

    2003-01-01

    An evolutionary algorithm based framework, a combination of modified breeder genetic algorithms incorporating characteristics of classic genetic algorithms, is utilized to design an offline/online path planner for unmanned aerial vehicles (UAVs) autonomous navigation. The path planner calculates a curved path line with desired characteristics in a three-dimensional (3-D) rough terrain environment, represented using B-spline curves, with the coordinates of its control points being the evolutionary algorithm artificial chromosome genes. Given a 3-D rough environment and assuming flight envelope restrictions, two problems are solved: i) UAV navigation using an offline planner in a known environment, and, ii) UAV navigation using an online planner in a completely unknown environment. The offline planner produces a single B-Spline curve that connects the starting and target points with a predefined initial direction. The online planner, based on the offline one, is given on-board radar readings which gradually produces a smooth 3-D trajectory aiming at reaching a predetermined target in an unknown environment; the produced trajectory consists of smaller B-spline curves smoothly connected with each other. Both planners have been tested under different scenarios, and they have been proven effective in guiding an UAV to its final destination, providing near-optimal curved paths quickly and efficiently.

  5. From large-eddy simulation to multi-UAVs sampling of shallow cumulus clouds

    NASA Astrophysics Data System (ADS)

    Lamraoui, Fayçal; Roberts, Greg; Burnet, Frédéric

    2016-04-01

    In-situ sampling of clouds that can provide simultaneous measurements at satisfying spatio-temporal resolutions to capture 3D small scale physical processes continues to present challenges. This project (SKYSCANNER) aims at bringing together cloud sampling strategies using a swarm of unmanned aerial vehicles (UAVs) based on Large-eddy simulation (LES). The multi-UAV-based field campaigns with a personalized sampling strategy for individual clouds and cloud fields will significantly improve the understanding of the unresolved cloud physical processes. An extensive set of LES experiments for case studies from ARM-SGP site have been performed using MesoNH model at high resolutions down to 10 m. The carried out simulations led to establishing a macroscopic model that quantifies the interrelationship between micro- and macrophysical properties of shallow convective clouds. Both the geometry and evolution of individual clouds are critical to multi-UAV cloud sampling and path planning. The preliminary findings of the current project reveal several linear relationships that associate many cloud geometric parameters to cloud related meteorological variables. In addition, the horizontal wind speed indicates a proportional impact on cloud number concentration as well as triggering and prolonging the occurrence of cumulus clouds. In the framework of the joint collaboration that involves a Multidisciplinary Team (including institutes specializing in aviation, robotics and atmospheric science), this model will be a reference point for multi-UAVs sampling strategies and path planning.

  6. Active landslide monitoring using remote sensing data, GPS measurements and cameras on board UAV

    NASA Astrophysics Data System (ADS)

    Nikolakopoulos, Konstantinos G.; Kavoura, Katerina; Depountis, Nikolaos; Argyropoulos, Nikolaos; Koukouvelas, Ioannis; Sabatakakis, Nikolaos

    2015-10-01

    An active landslide can be monitored using many different methods: Classical geotechnical measurements like inclinometer, topographical survey measurements with total stations or GPS and photogrammetric techniques using airphotos or high resolution satellite images. As the cost of the aerial photo campaign and the acquisition of very high resolution satellite data is quite expensive the use of cameras on board UAV could be an identical solution. Small UAVs (Unmanned Aerial Vehicles) have started their development as expensive toys but they currently became a very valuable tool in remote sensing monitoring of small areas. The purpose of this work is to demonstrate a cheap but effective solution for an active landslide monitoring. We present the first experimental results of the synergistic use of UAV, GPS measurements and remote sensing data. A six-rotor aircraft with a total weight of 6 kg carrying two small cameras has been used. Very accurate digital airphotos, high accuracy DSM, DGPS measurements and the data captured from the UAV are combined and the results are presented in the current study.

  7. UAV path planning using artificial potential field method updated by optimal control theory

    NASA Astrophysics Data System (ADS)

    Chen, Yong-bo; Luo, Guan-chen; Mei, Yue-song; Yu, Jian-qiao; Su, Xiao-long

    2016-04-01

    The unmanned aerial vehicle (UAV) path planning problem is an important assignment in the UAV mission planning. Based on the artificial potential field (APF) UAV path planning method, it is reconstructed into the constrained optimisation problem by introducing an additional control force. The constrained optimisation problem is translated into the unconstrained optimisation problem with the help of slack variables in this paper. The functional optimisation method is applied to reform this problem into an optimal control problem. The whole transformation process is deduced in detail, based on a discrete UAV dynamic model. Then, the path planning problem is solved with the help of the optimal control method. The path following process based on the six degrees of freedom simulation model of the quadrotor helicopters is introduced to verify the practicability of this method. Finally, the simulation results show that the improved method is more effective in planning path. In the planning space, the length of the calculated path is shorter and smoother than that using traditional APF method. In addition, the improved method can solve the dead point problem effectively.

  8. A UAV routing and sensor control optimization algorithm for target search

    NASA Astrophysics Data System (ADS)

    Collins, Gaemus E.; Riehl, James R.; Vegdahl, Philip S.

    2007-04-01

    An important problem in unmanned air vehicle (UAV) and UAV-mounted sensor control is the target search problem: locating target(s) in minimum time. Current methods solve the optimization of UAV routing control and sensor management independently. While this decoupled approach makes the target search problem computationally tractable, it is suboptimal. In this paper, we explore the target search and classification problems by formulating and solving a joint UAV routing and sensor control optimization problem. The routing problem is solved on a graph using receding horizon optimal control. The graph is dynamically adjusted based on the target probability distribution function (PDF). The objective function for the routing optimization is the solution of a sensor control optimization problem. An optimal sensor schedule (in the sense of maximizing the viewed target probability mass) is constructed for each candidate flight path in the routing control problem. The PDF of the target state is represented with a particle filter and an "occupancy map" for any undiscovered targets. The tradeoff between searching for undiscovered targets and locating tracks is handled automatically and dynamically by the use of an appropriate objective function. In particular, the objective function is based on the expected amount of target probability mass to be viewed.

  9. Hemispherical directional reflectance factor using UAV and a hyperspectral camera, validation and crop field test

    NASA Astrophysics Data System (ADS)

    Hakala, T.; Honkavaara, E.; Markelin, L.

    2014-10-01

    Small unmanned aerial vehicle (UAV) and a prototype hyperspectral imaging camera (HSI) was used to measure the hemispherical directional reflectance factor (HDRF) of a test field with known light scattering properties. The HSI acquires a burst of 24 images within two seconds and all of these images are acquired with different spectral content. By using the autopilot of the UAV, the flight can be preplanned so that the target area is optimally covered with overlapping images from multiple view angles. Structure from motion (SFM) algorithm is used to accurately determine the view angles for each image. The HDRF is calculated for each ground pixel by determining view directions from all of the images for that particular pixel. The pixel intensity values are then processed to reflectance by using a reference panel, which has been measured in laboratory with Finnish Geodetic Institute Field Goniospectrometer (FIGIFIGO). The UAV flight was performed over a test field with different gravel targets. The targets have known HDRF and this allows us to validate the UAV results. Another test was performed over a crop field to display the potential of this method for crop monitoring.

  10. The study of aerosol and ozone measurements in lower boundary layer with UAV helicopter platform

    NASA Astrophysics Data System (ADS)

    Lin, Po-hsiung; Chen, Wen-nai

    2013-04-01

    This study describes the aerosol and ozone measurement in the lower atmospheric boundary layer of highly polluted region at Kao-hsiung, Taiwan with a small unmanned aerial vehicle (UAV) helicopter platform. This UAV helicopter, modified from Gaui-X7 electronic-power model helicopter with autopilot AHRS (Altitude-Head-Reference System) kit, has fast climb speed up to 700 m height and keeps stable status for atmospheric measurements in five-minute fly leg. Several quick-replaced battery packages are ready on ground for field intensive observation. The payload rack under this UAV helicopter carries a micro-Aethalometer (black carbon concentration), ozone meter, temperature-humidity sensor, barometer and a time-lapse digital camera. The field measurement site closes to Linyuan Petrochemical Industrial Park, where is one of the heavy polluted regions in Taiwan. Balloon-borne Vaisala RS-92 radiosonde and CL31 Lidar Ceilometer are used to provide the background of the atmosphere at the same time. More data analysis measured by UAV helicopter and its potential application will be discussed.

  11. Particle swarm optimization method for the control of a fleet of Unmanned Aerial Vehicles

    NASA Astrophysics Data System (ADS)

    Belkadi, A.; Ciarletta, L.; Theilliol, D.

    2015-11-01

    This paper concerns a control approach of a fleet of Unmanned Aerial Vehicles (UAV) based on virtual leader. Among others, optimization methods are used to develop the virtual leader control approach, particularly the particle swarm optimization method (PSO). The goal is to find optimal positions at each instant of each UAV to guarantee the best performance of a given task by minimizing a predefined objective function. The UAVs are able to organize themselves on a 2D plane in a predefined architecture, following a mission led by a virtual leader and simultaneously avoiding collisions between various vehicles of the group. The global proposed method is independent from the model or the control of a particular UAV. The method is tested in simulation on a group of UAVs whose model is treated as a double integrator. Test results for the different cases are presented.

  12. Aerodynamics of Small Vehicles

    NASA Astrophysics Data System (ADS)

    Mueller, Thomas J.

    In this review we describe the aerodynamic problems that must be addressed in order to design a successful small aerial vehicle. The effects of Reynolds number and aspect ratio (AR) on the design and performance of fixed-wing vehicles are described. The boundary-layer behavior on airfoils is especially important in the design of vehicles in this flight regime. The results of a number of experimental boundary-layer studies, including the influence of laminar separation bubbles, are discussed. Several examples of small unmanned aerial vehicles (UAVs) in this regime are described. Also, a brief survey of analytical models for oscillating and flapping-wing propulsion is presented. These range from the earliest examples where quasi-steady, attached flow is assumed, to those that account for the unsteady shed vortex wake as well as flow separation and aeroelastic behavior of a flapping wing. Experiments that complemented the analysis and led to the design of a successful ornithopter are also described.

  13. Occurrence and carcinogenic potential of airborne polycyclic aromatic hydrocarbons in some large-scale enclosed/semi-enclosed vehicle parking areas.

    PubMed

    Li, Huiru; Zeng, Xiangying; Zhang, Delin; Chen, Pei; Yu, Zhiqiang; Sheng, Guoying; Fu, Jiamo; Peng, Ping'an

    2014-06-15

    Polycyclic aromatic hydrocarbons (PAHs) originating from vehicle exhaust have aroused much attention due to their potential healthy effect. In this study, air samples were collected from three representative parking lots in a metropolitan area, analyzed for PAHs and evaluated for inhalation risk. Atmospheric PAH levels of these parking areas ranged between 1,178-4,793 ng m(-3), one order of magnitude higher than general urban areas. Their benzo[a]pyrene equivalent (BaPeq) values varied in 11.0-98.0 ng m(-3), far exceeding the air quality standard of WHO (1.0 ng m(-3)). Monte Carlo simulation (100,000 trials) results suggest that the potential lifetime inhalation cancer risks of PAHs were 0.27 × 10(-5) to 7.11 × 10(-5) for park employees, which are in the acceptable range acknowledged by US EPA (1.0 × 10(-6) to 1.0 × 10(-4)). Several source diagnostic methods proved that vehicle exhaust was the dominant PAH contributor of these parks with the contribution percentages being >53%; oil combustion and/or coal combustion were other important sources. Logarithms of gas-particle distribution coefficients (Kps) of PAHs in all studied parks were linearly correlated with those of both their sub-cooled vapor pressures (pLs) and octanol-air partition coefficients (KOAs). The correlation coefficients indicated that both adsorption onto black carbon and absorption into organic matter were involved in the partition process, but the latter was dominant. PMID:24797904

  14. Estimation of canopy attributes in beech forests using true colour digital images from a small fixed-wing UAV

    NASA Astrophysics Data System (ADS)

    Chianucci, Francesco; Disperati, Leonardo; Guzzi, Donatella; Bianchini, Daniele; Nardino, Vanni; Lastri, Cinzia; Rindinella, Andrea; Corona, Piermaria

    2016-05-01

    Accurate estimates of forest canopy are essential for the characterization of forest ecosystems. Remotely-sensed techniques provide a unique way to obtain estimates over spatially extensive areas, but their application is limited by the spectral and temporal resolution available from these systems, which is often not suited to meet regional or local objectives. The use of unmanned aerial vehicles (UAV) as remote sensing platforms has recently gained increasing attention, but their applications in forestry are still at an experimental stage. In this study we described a methodology to obtain rapid and reliable estimates of forest canopy from a small UAV equipped with a commercial RGB camera. The red, green and blue digital numbers were converted to the green leaf algorithm (GLA) and to the CIE L*a*b* colour space to obtain estimates of canopy cover, foliage clumping and leaf area index (L) from aerial images. Canopy attributes were compared with in situ estimates obtained from two digital canopy photographic techniques (cover and fisheye photography). The method was tested in beech forests. UAV images accurately quantified canopy cover even in very dense stand conditions, despite a tendency to not detecting small within-crown gaps in aerial images, leading to a measurement of a quantity much closer to crown cover estimated from in situ cover photography. Estimates of L from UAV images significantly agreed with that obtained from fisheye images, but the accuracy of UAV estimates is influenced by the appropriate assumption of leaf angle distribution. We concluded that true colour UAV images can be effectively used to obtain rapid, cheap and meaningful estimates of forest canopy attributes at medium-large scales. UAV can combine the advantage of high resolution imagery with quick turnaround series, being therefore suitable for routine forest stand monitoring and real-time applications.

  15. Comparison of Uncalibrated Rgbvi with Spectrometer-Based Ndvi Derived from Uav Sensing Systems on Field Scale

    NASA Astrophysics Data System (ADS)

    Bareth, G.; Bolten, A.; Gnyp, M. L.; Reusch, S.; Jasper, J.

    2016-06-01

    The development of UAV-based sensing systems for agronomic applications serves the improvement of crop management. The latter is in the focus of precision agriculture which intends to optimize yield, fertilizer input, and crop protection. Besides, in some cropping systems vehicle-based sensing devices are less suitable because fields cannot be entered from certain growing stages onwards. This is true for rice, maize, sorghum, and many more crops. Consequently, UAV-based sensing approaches fill a niche of very high resolution data acquisition on the field scale in space and time. While mounting RGB digital compact cameras to low-weight UAVs (< 5 kg) is well established, the miniaturization of sensors in the last years also enables hyperspectral data acquisition from those platforms. From both, RGB and hyperspectral data, vegetation indices (VIs) are computed to estimate crop growth parameters. In this contribution, we compare two different sensing approaches from a low-weight UAV platform (< 5 kg) for monitoring a nitrogen field experiment of winter wheat and a corresponding farmers' field in Western Germany. (i) A standard digital compact camera was flown to acquire RGB images which are used to compute the RGBVI and (ii) NDVI is computed from a newly modified version of the Yara N-Sensor. The latter is a well-established tractor-based hyperspectral sensor for crop management and is available on the market since a decade. It was modified for this study to fit the requirements of UAV-based data acquisition. Consequently, we focus on three objectives in this contribution: (1) to evaluate the potential of the uncalibrated RGBVI for monitoring nitrogen status in winter wheat, (2) investigate the UAV-based performance of the modified Yara N-Sensor, and (3) compare the results of the two different UAV-based sensing approaches for winter wheat.

  16. A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment

    PubMed Central

    Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi

    2016-01-01

    This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments. PMID:27589755

  17. A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment.

    PubMed

    Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi

    2016-08-30

    This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments.

  18. A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment.

    PubMed

    Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi

    2016-01-01

    This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments. PMID:27589755

  19. Joint Processing of Uav Imagery and Terrestrial Mobile Mapping System Data for Very High Resolution City Modeling

    NASA Astrophysics Data System (ADS)

    Gruen, A.; Huang, X.; Qin, R.; Du, T.; Fang, W.; Boavida, J.; Oliveira, A.

    2013-08-01

    Both unmanned aerial vehicle (UAV) technology and Mobile Mapping Systems (MMS) are important techniques for surveying and mapping. In recent years, the UAV technology has seen tremendous interest, both in the mapping community and in many other fields of application. Carrying off-the shelf digital cameras, the UAV can collect high quality aerial optical images for city modeling using photogrammetric techniques. In addition, a MMS can acquire high density point clouds of ground objects along the roads. The UAV, if operated in an aerial mode, has difficulties in acquiring information of ground objects under the trees and along façades of buildings. On the contrary, the MMS collects accurate point clouds of objects from the ground, together with stereo images, but it suffers from system errors due to loss of GPS signals, and also lacks the information of the roofs. Therefore, both technologies are complementary. This paper focuses on the integration of UAV images, MMS point cloud data and terrestrial images to build very high resolution 3D city models. The work we will show is a practical modeling project of the National University of Singapore (NUS) campus, which includes buildings, some of them very high, roads and other man-made objects, dense tropical vegetation and DTM. This is an intermediate report. We present work in progress.

  20. Visual Servoing for a Quadrotor UAV in Target Tracking Applications

    NASA Astrophysics Data System (ADS)

    Popova, Marinela Georgieva

    This research study investigates the design and implementation of position-based and image-based visual servoing techniques for controlling the motion of quadrotor unmanned aerial vehicles (UAVs). The primary applications considered are tracking stationary and moving targets. A novel position-based tracking law is developed and integrated with inner loop proportional-integral-derivative control algorithm. A theoretical proof for the stability of the proposed method is provided and numerical simulations are performed to validate the performance of the closed-loop system. A classical image-based visual servoing technique is also implemented and a modification of the classical method is suggested to reduce the undesirable effects due to the underactuated quadrotor system. Finally, the case when the quadrotor loses sight of the target is investigated and several solutions are proposed to help maintain the view of the target.

  1. An Evaluation of Protocols for UAV Science Applications

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Stewart, David E.; Sullivan, Donald V.; Finch, Patrick E.

    2012-01-01

    This paper identifies data transport needs for current and future science payloads deployed on the NASA Global Hawk Unmanned Aeronautical Vehicle (UAV). The NASA Global Hawk communication system and operational constrains are presented. The Genesis and Rapid Intensification Processes (GRIP) mission is used to provide the baseline communication requirements as a variety of payloads were utilized in this mission. User needs and desires are addressed. Protocols are matched to the payload needs and an evaluation of various techniques and tradeoffs are presented. Such techniques include utilization rate-base selective negative acknowledgement protocols and possible use of protocol enhancing proxies. Tradeoffs of communication architectures that address ease-of-use and security considerations are also presented.

  2. Nonlinear Aeroelastic Analysis of UAVs: Deterministic and Stochastic Approaches

    NASA Astrophysics Data System (ADS)

    Sukut, Thomas Woodrow

    Aeroelastic aspects of unmanned aerial vehicles (UAVs) is analyzed by treatment of a typical section containing geometrical nonlinearities. Equations of motion are derived and numerical integration of these equations subject to quasi-steady aerodynamic forcing is performed. Model properties are tailored to a high-altitude long-endurance unmanned aircraft. Harmonic balance approximation is employed based on the steady-state oscillatory response of the aerodynamic forcing. Comparisons are made between time integration results and harmonic balance approximation. Close agreement between forcing and displacement oscillatory frequencies is found. Amplitude agreement is off by a considerable margin. Additionally, stochastic forcing effects are examined. Turbulent flow velocities generated from the von Karman spectrum are applied to the same nonlinear structural model. Similar qualitative behavior is found between quasi-steady and stochastic forcing models illustrating the importance of considering the non-steady nature of atmospheric turbulence when operating near critical flutter velocity.

  3. UAV-based high-throughput phenotyping in legume crops

    NASA Astrophysics Data System (ADS)

    Sankaran, Sindhuja; Khot, Lav R.; Quirós, Juan; Vandemark, George J.; McGee, Rebecca J.

    2016-05-01

    In plant breeding, one of the biggest obstacles in genetic improvement is the lack of proven rapid methods for measuring plant responses in field conditions. Therefore, the major objective of this research was to evaluate the feasibility of utilizing high-throughput remote sensing technology for rapid measurement of phenotyping traits in legume crops. The plant responses of several chickpea and peas varieties to the environment were assessed with an unmanned aerial vehicle (UAV) integrated with multispectral imaging sensors. Our preliminary assessment showed that the vegetation indices are strongly correlated (p<0.05) with seed yield of legume crops. Results endorse the potential of UAS-based sensing technology to rapidly measure those phenotyping traits.

  4. A solar module fabrication process for HALE solar electric UAVs

    SciTech Connect

    Carey, P.G.; Aceves, R.C.; Colella, N.J.; Williams, K.A.; Sinton, R.A.; Glenn, G.S.

    1994-12-12

    We describe a fabrication process used to manufacture high power-to-weight-ratio flexible solar array modules for use on high-altitude-long-endurance (HALE) solar-electric unmanned air vehicles (UAVs). These modules have achieved power-to-weight ratios of 315 and 396 W/kg for 150{mu}m-thick monofacial and 110{mu}m-thick bifacial silicon solar cells, respectively. These calculations reflect average module efficiencies of 15.3% (150{mu}m) and 14.7% (110{mu}m) obtained from electrical tests performed by Spectrolab, Inc. under AMO global conditions at 25{degrees}C, and include weight contributions from all module components (solar cells, lamination material, bypass diodes, interconnect wires, and adhesive tape used to attach the modules to the wing). The fabrication, testing, and performance of 32 m{sup 2} of these modules will be described.

  5. Nonlinear speed estimation of a GPS-free UAV

    NASA Astrophysics Data System (ADS)

    Santosuosso, Giovanni L.; Benzemrane, Khadidja; Damm, Gilney

    2011-11-01

    In this article, the problem of robust state observer design for a class of unmanned aerial vehicles (UAVs) is addressed. A prototype four-rotors helicopter robot for indoors and outdoors applications is considered: the drone is not equipped with GPS related devices, so we describe a strategy to estimate its translational velocity vector based on acceleration, angles and angular speeds measurements only. Since the linearised system is non-observable at the equilibrium point, a nonlinear observability verification is performed for persistently exciting trajectories. A global exponential solution to this open problem is provided in the framework of adaptive observation theory when exact measurements are available. A modified observer is presented to enhance velocity estimation robustness in the realistic case of noisy measurements. The results are compared with a classical estimation strategy based on the extended Kalman filter to test the algorithm's performance.

  6. Evaluating the accuracy of low cost UAV generated topography and its effectiveness for geomorphic change detection

    NASA Astrophysics Data System (ADS)

    Cook, Kristen

    2015-04-01

    With the recent explosion in the use and availability of unmanned aerial vehicle platforms and development of easy to use structure from motion (SfM) software, UAV based photogrammetry is increasingly being adopted to produce high resolution topography for the study of surface processes. UAV systems can vary substantially in price and complexity, but the tradeoffs between these and the quality of the resulting data are not well constrained. We look at one end of this spectrum and evaluate the effectiveness of a simple low cost UAV setup for obtaining high resolution topography in a challenging field setting. Our study site is the Daan River gorge in western Taiwan, a rapidly eroding bedrock gorge that we have monitored with terrestrial Lidar since 2009. The site presents challenges for the generation and analysis of high resolution topography, including vertical gorge walls, vegetation, wide variation in surface roughness, and a complicated 3D morphology. In order to evaluate the accuracy of the UAV-derived topography, we compare it with terrestrial Lidar data collected during the same survey period. Our UAV setup combines a DJI Phantom 2 quadcopter with a 16 megapixel Canon Powershot camera for a total platform cost of less than 850. The quadcopter is flown manually, and the camera is programmed to take a photograph every 4 seconds, yielding 200-250 pictures per flight. We measured ground control points and targets for both the Lidar scans and the aerial surveys using a Leica RTK GPS with 1-2 cm accuracy. UAV derived point clouds were obtained using Agisoft Photoscan software. We conducted both Lidar and UAV surveys before and after the 2014 typhoon season, allowing us to evaluate the reliability of the UAV survey to detect geomorphic changes in the range of one to several meters. The accuracy of the SfM point clouds depends strongly on the characteristics of the surface being considered, with vegetation and small scale texture causing inaccuracies. However, we