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1

Navigation system of pilotless aircraft via GPS  

Microsoft Academic Search

The pilotless aircraft has wide applications in measuring earth, surveying mineral sources, fireproofing in the forest, observing floods and so on. In this paper, after briefly introducing positioning and navigation technologies for pilotless aircraft-a new kind of navigation system for pilotless aircraft using GPS (Global Positioning System) is presented. An overall plan of the navigation system is discussed, and its

Yongsheng Wang; Xiangpeng Li; Yong Huang

1996-01-01

2

GPS Supplemental Navigation Systems for Use During the Transition to a Sole-Means-GPS  

E-print Network

GPS Supplemental Navigation Systems for Use During the Transition to a Sole-Means-GPS National as part of the transition to sole-means-GPS navigation in the United States. GPS based systems are also radio-navigation aids to provide a redundant navigation system alongside GPS/WAAS during the transition

Stanford University

3

Flight test on GPS navigation performance using low cost GPS navigation system  

Microsoft Academic Search

Summary form only given. The author describes a flight test performed in Japan using a GPS (Global Positioning System) navigation system. A low-cost C\\/A code GPS navigation system (Pioneer AVIC-1) which consists of a three-channel sequential receiver and map display was installed on an experimental aircraft together with VOR\\/DME airborne experiment and a baro-altimeter. The data collected are position, velocity

K. Koremura

1992-01-01

4

Autonomous navigation system based on GPS and magnetometer data  

NASA Technical Reports Server (NTRS)

This invention is drawn to an autonomous navigation system using Global Positioning System (GPS) and magnetometers for low Earth orbit satellites. As a magnetometer is reliable and always provides information on spacecraft attitude, rate, and orbit, the magnetometer-GPS configuration solves GPS initialization problem, decreasing the convergence time for navigation estimate and improving the overall accuracy. Eventually the magnetometer-GPS configuration enables the system to avoid costly and inherently less reliable gyro for rate estimation. Being autonomous, this invention would provide for black-box spacecraft navigation, producing attitude, orbit, and rate estimates without any ground input with high accuracy and reliability.

Julie, Thienel K. (Inventor); Richard, Harman R. (Inventor); Bar-Itzhack, Itzhack Y. (Inventor)

2004-01-01

5

GPS-NAVSTAR The navigation system of the future  

Microsoft Academic Search

The various types of navigation procedures are examined, taking into account also techniques for determining the position of an aircraft with the aid of satellites. The Global Positioning System (GPS) is a satellite navigation system which has been introduced by the U.S. Department of Defense for continuous, highly accurate determinations of position, time, and velocity. It is expected that the

A. Stiller

1981-01-01

6

77 FR 35428 - Certain Automotive GPS Navigation Systems, Components Thereof, and Products Containing Same...  

Federal Register 2010, 2011, 2012, 2013

...337-TA-814] Certain Automotive GPS Navigation Systems, Components Thereof...a show cause order and an initial determination (``ID...complaint filed by Beacon Navigation GmbH of Zug, Switzerland...of certain automotive GPS navigation systems, components...

2012-06-13

7

76 FR 66750 - Certain Automotive GPS Navigation Systems, Components Thereof, and Products Containing Same...  

Federal Register 2010, 2011, 2012, 2013

...Re Certain Automotive GPS Navigation Systems, Components Thereof...filed on behalf of Beacon Navigation Gmbh on October 21, 2011...of certain automotive gps navigation systems, components thereof...the issuance of any final initial determination in this...

2011-10-27

8

High accuracy autonomous navigation using the global positioning system (GPS)  

NASA Technical Reports Server (NTRS)

The application of global positioning system (GPS) technology to the improvement of the accuracy and economy of spacecraft navigation, is reported. High-accuracy autonomous navigation algorithms are currently being qualified in conjunction with the GPS attitude determination flyer (GADFLY) experiment for the small satellite technology initiative Lewis spacecraft. Preflight performance assessments indicated that these algorithms are able to provide a real time total position accuracy of better than 10 m and a velocity accuracy of better than 0.01 m/s, with selective availability at typical levels. It is expected that the position accuracy will be increased to 2 m if corrections are provided by the GPS wide area augmentation system.

Truong, Son H.; Hart, Roger C.; Shoan, Wendy C.; Wood, Terri; Long, Anne C.; Oza, Dipak H.; Lee, Taesul

1997-01-01

9

Flight evaluation of differential GPS aided inertial navigation systems  

NASA Technical Reports Server (NTRS)

Algorithms are described for integration of Differential Global Positioning System (DGPS) data with Inertial Navigation System (INS) data to provide an integrated DGPS/INS navigation system. The objective is to establish the benefits that can be achieved through various levels of integration of DGPS with INS for precision navigation. An eight state Kalman filter integration was implemented in real-time on a twin turbo-prop transport aircraft to evaluate system performance during terminal approach and landing operations. A fully integrated DGPS/INS system is also presented which models accelerometer and rate-gyro measurement errors plus position, velocity, and attitude errors. The fully integrated system was implemented off-line using range-domain (seventeen-state) and position domain (fifteen-state) Kalman filters. Both filter integration approaches were evaluated using data collected during the flight test. Flight-test data consisted of measurements from a 5 channel Precision Code GPS receiver, a strap-down Inertial Navigation Unit (INU), and GPS satellite differential range corrections from a ground reference station. The aircraft was laser tracked to determine its true position. Results indicate that there is no significant improvement in positioning accuracy with the higher levels of DGPS/INS integration. All three systems provided high-frequency (e.g., 20 Hz) estimates of position and velocity. The fully integrated system provided estimates of inertial sensor errors which may be used to improve INS navigation accuracy should GPS become unavailable, and improved estimates of acceleration, attitude, and body rates which can be used for guidance and control. Precision Code DGPS/INS positioning accuracy (root-mean-square) was 1.0 m cross-track and 3.0 m vertical. (This AGARDograph was sponsored by the Guidance and Control Panel.)

Mcnally, B. David; Paielli, Russell A.; Bach, Ralph E., Jr.; Warner, David N., Jr.

1992-01-01

10

Evaluation of Mobile Phone Interference With Aircraft GPS Navigation Systems  

NASA Technical Reports Server (NTRS)

This report compiles and analyzes tests that were conducted to measure cell phone spurious emissions in the Global Positioning System (GPS) radio frequency band that could affect the navigation system of an aircraft. The cell phone in question had, as reported to the FAA (Federal Aviation Administration), caused interference to several GPS receivers on-board a small single engine aircraft despite being compliant with data filed at the time with the FCC by the manufacturer. NASA (National Aeronautics and Space Administration) and industry tests show that while there is an emission in the 1575 MHz GPS band due to a specific combination of amplifier output impedance and load impedance that induces instability in the power amplifier, these spurious emissions (i.e., not the intentional transmit signal) are similar to those measured on non-intentionally transmitting devices such as, for example, laptop computers. Additional testing on a wide sample of different commercial cell phones did not result in any emission in the 1575 MHz GPS Band above the noise floor of the measurement receiver.

Pace, Scott; Oria, A. J.; Guckian, Paul; Nguyen, Truong X.

2004-01-01

11

Testing and evaluation of an integrated GPS\\/INS system for small AUV navigation  

Microsoft Academic Search

A Small Autonomous Underwater Vehicle Navigation System (SANS) is being developed at the Naval Postgraduate School. The SANS is an integrated Global Positioning System\\/Inertial Navigation System (GPS\\/INS) navigation system composed of low-cost and small-size components. It is designed to demonstrate the feasibility of using a low-cost strap-down inertial measurement unit (IMU) to navigate between intermittent GPS fixes. The present hardware

X. Yun; E. R. Bachmann; R. B. McGhee; R. H. Whalen; R. L. Roberts; R. G. Knapp; A. J. Healey; M. J. Zyda

1999-01-01

12

Development of a GPS/INS/MAG navigation system and waypoint navigator for a VTOL UAV  

NASA Astrophysics Data System (ADS)

Unmanned aerial vehicles (UAV) can be used for versatile surveillance and reconnaissance missions. If a UAV is capable of flying automatically on a predefined path the range of possible applications is widened significantly. This paper addresses the development of the integrated GPS/INS/MAG navigation system and a waypoint navigator for a small vertical take-off and landing (VTOL) unmanned four-rotor helicopter with a take-off weight below 1 kg. The core of the navigation system consists of low cost inertial sensors which are continuously aided with GPS, magnetometer compass, and a barometric height information. Due to the fact, that the yaw angle becomes unobservable during hovering flight, the integration with a magnetic compass is mandatory. This integration must be robust with respect to errors caused by the terrestrial magnetic field deviation and interferences from surrounding electronic devices as well as ferrite metals. The described integration concept with a Kalman filter overcomes the problem that erroneous magnetic measurements yield to an attitude error in the roll and pitch axis. The algorithm provides long-term stable navigation information even during GPS outages which is mandatory for the flight control of the UAV. In the second part of the paper the guidance algorithms are discussed in detail. These algorithms allow the UAV to operate in a semi-autonomous mode position hold as well an complete autonomous waypoint mode. In the position hold mode the helicopter maintains its position regardless of wind disturbances which ease the pilot job during hold-and-stare missions. The autonomous waypoint navigator enable the flight outside the range of vision and beyond the range of the radio link. Flight test results of the implemented modes of operation are shown.

Meister, Oliver; Mönikes, Ralf; Wendel, Jan; Frietsch, Natalie; Schlaile, Christian; Trommer, Gert F.

2007-04-01

13

78 FR 68861 - Certain Navigation Products, Including GPS Devices, Navigation and Display Systems, Radar Systems...  

Federal Register 2010, 2011, 2012, 2013

...Navigational Aids, Mapping Systems and Related Software; Institution of Investigation Pursuant...navigational aids, mapping systems and related software by reason of infringement of certain...navigational aids, mapping systems and related software by reason of infringement of one or...

2013-11-15

14

The performance analysis of a real-time integrated INS/GPS vehicle navigation system with abnormal GPS measurement elimination.  

PubMed

The integration of an Inertial Navigation System (INS) and the Global Positioning System (GPS) is common in mobile mapping and navigation applications to seamlessly determine the position, velocity, and orientation of the mobile platform. In most INS/GPS integrated architectures, the GPS is considered to be an accurate reference with which to correct for the systematic errors of the inertial sensors, which are composed of biases, scale factors and drift. However, the GPS receiver may produce abnormal pseudo-range errors mainly caused by ionospheric delay, tropospheric delay and the multipath effect. These errors degrade the overall position accuracy of an integrated system that uses conventional INS/GPS integration strategies such as loosely coupled (LC) and tightly coupled (TC) schemes. Conventional tightly coupled INS/GPS integration schemes apply the Klobuchar model and the Hopfield model to reduce pseudo-range delays caused by ionospheric delay and tropospheric delay, respectively, but do not address the multipath problem. However, the multipath effect (from reflected GPS signals) affects the position error far more significantly in a consumer-grade GPS receiver than in an expensive, geodetic-grade GPS receiver. To avoid this problem, a new integrated INS/GPS architecture is proposed. The proposed method is described and applied in a real-time integrated system with two integration strategies, namely, loosely coupled and tightly coupled schemes, respectively. To verify the effectiveness of the proposed method, field tests with various scenarios are conducted and the results are compared with a reliable reference system. PMID:23955434

Chiang, Kai-Wei; Duong, Thanh Trung; Liao, Jhen-Kai

2013-01-01

15

Modular Software for Spacecraft Navigation Using the Global Positioning System (GPS)  

NASA Technical Reports Server (NTRS)

The Goddard Space Flight Center Flight Dynamics and Mission Operations Divisions have jointly investigated the feasibility of engineering modular Global Positioning SYSTEM (GPS) navigation software to support both real time flight and ground postprocessing configurations. The goals of this effort are to define standard GPS data interfaces and to engineer standard, reusable navigation software components that can be used to build a broad range of GPS navigation support applications. The paper discusses the GPS modular software (GMOD) system and operations concepts, major requirements, candidate software architecture, feasibility assessment and recommended software interface standards. In additon, ongoing efforts to broaden the scope of the initial study and to develop modular software to support autonomous navigation using GPS are addressed,

Truong, S. H.; Hartman, K. R.; Weidow, D. A.; Berry, D. L.; Oza, D. H.; Long, A. C.; Joyce, E.; Steger, W. L.

1996-01-01

16

Integrated GPS/INS navigation system design for autonomous spacecraft rendezvous  

NASA Astrophysics Data System (ADS)

The goal of the NASA Space Launch Initiative (SLI) program is to advance the technologies for the next generation reusable launch vehicle (RLV). The SLI program has identified automated rendezvous and docking as an area requiring further research and development. Currently, the Space Shuttle uses a partially manual system for rendezvous, but a fully automated system could be safer and more reliable. Previous studies have shown that it is feasible to use the Global Positioning System (GPS) for spacecraft navigation during rendezvous with the International Space Station (ISS). However, these studies have not accounted for the effects of GPS signal blockage and multipath in the vicinity of the ISS, which make a GPS-only navigation system less accurate and reliable. One possible solution is to combine GPS with an inertial navigation system (INS). The integration of GPS and INS can be achieved using a Kalman filter. GPS/INS systems have been used in aircraft for many years and have also been used in launch vehicles. However, the performance of GPS/INS systems in orbit and during spacecraft rendezvous has not been characterized. The primary objective of this research is to evaluate the ability of an integrated GPS/INS to provide accurate navigation solutions during a rendezvous scenario where the effects of ISS signal blockage, multipath and delta-v maneuvers degrade GPS-only navigation. In order to accomplish this, GPS-only and GPS/INS Kalman filters have been developed for both absolute and relative navigation, as well as a new statistical multipath model for spacecraft operating near the ISS. Several factors that affect relative navigation performance were studied, including: filter tuning, GPS constellation geometry, rendezvous approach direction, and inertial sensor performance. The results showed that each of these factors has a large impact on relative navigation performance. Finally, it has been demonstrated that a GPS/INS system based on medium accuracy aircraft avionics-grade inertial sensors does not provide adequate relative navigation performance for rendezvous with the ISS unless accelerometer thresholding is used. However, the use of state-of-the-art inertial navigation sensors provides relative position accuracy which is adequate for rendezvous with ISS if an additional rendezvous sensor is included.

Gaylor, David Edward

2003-10-01

17

Evaluation of an integrated GPS\\/INS system for shallow-water AUV navigation (SANS)  

Microsoft Academic Search

Many possible autonomous underwater vehicle (AUV) missions require a high degree of navigational accuracy. The Global Positioning System (GPS) is capable of providing this accuracy. However, intermittent reception caused by either wave action or deliberate submergence will cause the loss of GPS position fix information for periods extending from several seconds to minutes. The SANS system is designed to demonstrate

E. R. Bachmann; R. B. McGhee; R. H. Whalen; R. Steven; R. G. Walker; J. R. Clynch; A. J. Healey; X. P. Yun

1996-01-01

18

A DME based area navigation systems for GPS\\/WAAS interference mitigation in general aviation applications  

Microsoft Academic Search

The Federal Aviation Administration is leading the National Airspace System modernization effort, in part by supplanting traditional air traffic services with GPS aided by the wide and local area augmentation systems (WAAS & LAAS). Making GPS the sole-means of navigation will enhance safety, flexibility and efficiency of operations for all aircraft ranging from the single engine general aviation aircraft to

Demoz Gebre-Egziabher; J. David Powell; Per Enge

2000-01-01

19

Observability and performance analysis of integrated GPS\\/INS navigation systems  

Microsoft Academic Search

This primary objective of this thesis is to analyze the performance and observability characteristics of integrated navigation systems which fuse the information from the Global Positioning System (GPS) and Inertial Navigation Systems (INS) of varying quality. It is shown that INS output error characteristics affect the notion of observability with these systems. More specifically; it is shown that when INS

Yunfeng Shao

2006-01-01

20

Design of a low-cost attitude determination GPS\\/INS integrated navigation system  

Microsoft Academic Search

Due to their complementary features of GPS and INS, the GPS\\/INS integrated navigation system is increasingly being used for\\u000a a variety of commercial and military applications. An attitude determination GPS (ADGPS) receiver, with multiple antennas,\\u000a can be more effectively integrated with a low-cost IMU since the receiver gives not only position and velocity data but also\\u000a attitude data. This paper

Dong-Hwan Hwang; Sang Heon Oh; Sang Jeong Lee; Chris Rizos

2005-01-01

21

Error Analysis System for Spacecraft Navigation Using the Global Positioning System (GPS)  

NASA Technical Reports Server (NTRS)

The Flight Dynamics Division (FDD) at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) is currently developing improved space-navigation filtering algorithms to use the Global Positioning System (GPS) for autonomous real-time onboard orbit determination. In connection with a GPS technology demonstration on the Small Satellite Technology Initiative (SSTI)/Lewis spacecraft, FDD analysts and programmers have teamed with the GSFC Guidance, Navigation, and Control Branch to develop the GPS Enhanced Orbit Determination Experiment (GEODE) system. The GEODE system consists of a Kalman filter operating as a navigation tool for estimating the position, velocity, and additional states required to accurately navigate the orbiting Lewis spacecraft by using astrodynamic modeling and GPS measurements from the receiver. A parallel effort at the FDD is the development of a GPS Error Analysis System (GEAS) that will be used to analyze and improve navigation filtering algorithms during development phases and during in-flight calibration. For GEAS, the Kalman filter theory is extended to estimate the errors in position, velocity, and other error states of interest. The estimation of errors in physical variables at regular intervals will allow the time, cause, and effect of navigation system weaknesses to be identified. In addition, by modeling a sufficient set of navigation system errors, a system failure that causes an observed error anomaly can be traced and accounted for. The GEAS software is formulated using Object Oriented Design (OOD) techniques implemented in the C++ programming language on a Sun SPARC workstation. The Phase 1 of this effort is the development of a basic system to be used to evaluate navigation algorithms implemented in the GEODE system. This paper presents the GEAS mathematical methodology, systems and operations concepts, and software design and implementation. Results from the use of the basic system to evaluate navigation algorithms implemented on GEODE are also discussed. In addition, recommendations for generalization of GEAS functions and for new techniques to optimize the accuracy and control of the GPS autonomous onboard navigation are presented.

Truong, S. H.; Hart, R. C.; Hartman, K. R.; Tomcsik, T. L.; Searl, J. E.; Bernstein, A.

1997-01-01

22

76 FR 72442 - Certain Automotive GPS Navigation Systems, Components Thereof, and Products Containing Same...  

Federal Register 2010, 2011, 2012, 2013

...importation of certain automotive GPS navigation systems, components thereof, and products...served: (a) The complainant is: Beacon Navigation GmbH, c/o Acton Treuhand AG, Innere...complaint and this notice and to enter an initial determination and a final...

2011-11-23

23

GPS navigation requirements for future mobile ground-based missile systems  

NASA Astrophysics Data System (ADS)

It is pointed out that at any given time there are several different missile systems under development. Each of these systems requires some form of guidance or navigation system. In the past, this requirement has been met through the use of inertial sensors. To meet future system requriements, it is envisioned that it will be necessary to incorporate GPS (Global Positioning System) receivers on the launchers and into the missiles. The size, weight, power, performance, number of channels, and cost of these GPS receivers are critical. The authors outline capabilities future GPS receivers will need to meet envisioned US Army missile system requirements.

Graham, Greg; Killen, Albert

24

A Self-Tuning Kalman Filter for Autonomous Navigation Using the Global Positioning System (GPS)  

NASA Technical Reports Server (NTRS)

Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS (Global Positioning Systems) data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.

Truong, Son H.

1999-01-01

25

A LOW-COST GPS AIDED INERTIAL NAVIGATION SYSTEM FOR VEHICLE APPLICATIONS  

Microsoft Academic Search

In this paper an approach for integration between GPS and inertial navigation systems (INS) is described. The continuous-time nav- igation and error equations for an earth-centered earth-fixed INS system are presented. Using zero order hold sampling, the set of equations is discretized. An extended Kalman filter for closed loop integration between the GPS and INS is derived. The filter propa-

Isaac Skog; Peter H

26

A Self-Tuning Kalman Filter for Autonomous Navigation using the Global Positioning System (GPS)  

NASA Technical Reports Server (NTRS)

Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.

Truong, S. H.

1999-01-01

27

Integrated Inertial Navigation System\\/Global Positioning System (INS\\/GPS) for automatic space return vehicle  

Microsoft Academic Search

A digital GN&C system that automatically returns a space vehicle from orbit to a precision touchdown\\/landing is described. It is demonstrated that a capsule or lifting body manned return vehicle (MRV) with integrated INS\\/GPS (inertial navigation system\\/global positioning system) provides a highly autonomous and automatic deorbit, entry, and precision landing capability. Simulation results are used to demonstrate automatic MRV landing

Kevin Braden; Clint Browning; Hendrik Gelderloos

1990-01-01

28

Application of adaptive UKF in initial alignment of MINS\\/GPS integrated navigation system  

Microsoft Academic Search

In order to overcome the shortcomings of standard unscented Kalman filter (UKF), which are obviously influenced by the error of initial value and the model error of system, adaptive UKF which is based on the adaptive principle is applied in initial alignment of the MINS\\/GPS integrated navigation system. Coarse alignment cannot be done by micro inertial measurement unit (MIMU) itself

Wei-bo Jiao; Wan-xin Su; Qiang Gao; Min Wang

2010-01-01

29

Verification of Robustified Kalman Filters for the Integration of Global Positioning System (GPS) and Inertial Navigation System (INS) Data.  

National Technical Information Service (NTIS)

The purpose of this research is to compare the effects of two filtering routines which may be used to integrate Inertial Navigation System (INS) and Global Positioning System (GPS) data to determine certain state vector elements. The two filtering routine...

J. W. Haak

1994-01-01

30

Towards an Intelligent GPS-Based Vehicle Navigation System for Finding Street Parking Lots  

Microsoft Academic Search

Current GPS-based vehicle navigation systems provide drivers with information about the location and the availability of a parking lot near the specified destination. However, this availability information is provided based only on the current state of the parking lot. Therefore, they fail to predict whether the vehicle would be able to get a parking lot when it actually arrives. In

S. Pullola; P. K. Atrey; A. El Saddik

2007-01-01

31

Autonomous Navigation of the SSTI/Lewis Spacecraft Using the Global Positioning System (GPS)  

NASA Technical Reports Server (NTRS)

The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) is pursuing the application of Global Positioning System (GPS) technology to improve the accuracy and economy of spacecraft navigation. High-accuracy autonomous navigation algorithms are being flight qualified in conjunction with GSFC's GPS Attitude Determination Flyer (GADFLY) experiment on the Small Satellite Technology Initiative (SSTI) Lewis spacecraft, which is scheduled for launch in 1997. Preflight performance assessments indicate that these algorithms can provide a real-time total position accuracy of better than 10 meters (1 sigma) and velocity accuracy of better than 0.01 meter per second (1 sigma), with selective availability at typical levels. This accuracy is projected to improve to the 2-meter level if corrections to be provided by the GPS Wide Area Augmentation System (WAAS) are included.

Hart, R. C.; Long, A. C.; Lee, T.

1997-01-01

32

Space Shuttle Navigation in the GPS Era  

NASA Technical Reports Server (NTRS)

The Space Shuttle navigation architecture was originally designed in the 1970s. A variety of on-board and ground based navigation sensors and computers are used during the ascent, orbit coast, rendezvous, (including proximity operations and docking) and entry flight phases. With the advent of GPS navigation and tightly coupled GPS/INS Units employing strapdown sensors, opportunities to improve and streamline the Shuttle navigation process are being pursued. These improvements can potentially result in increased safety, reliability, and cost savings in maintenance through the replacement of older technologies and elimination of ground support systems (such as Tactical Air Control and Navigation (TACAN), Microwave Landing System (MLS) and ground radar). Selection and missionization of "off the shelf" GPS and GPS/INS units pose a unique challenge since the units in question were not originally designed for the Space Shuttle application. Various options for integrating GPS and GPS/INS units with the existing orbiter avionics system were considered in light of budget constraints, software quality concerns, and schedule limitations. An overview of Shuttle navigation methodology from 1981 to the present is given, along with how GPS and GPS/INS technology will change, or not change, the way Space Shuttle navigation is performed in the 21 5 century.

Goodman, John L.

2001-01-01

33

GPS and UWB for indoor navigation  

Microsoft Academic Search

A multitude of applications would benefit from precise indoor navigation. Anywhere from automating storage in warehouses to tracking firemen in hazardous environments would make such an endeavor worthwhile. Some server-based GPS systems, like SnapTrack, already claim some navigation capabilities indoors. However, such systems are in general accurate to within a few tens of meters. Furthermore, pseudolites have been deployed for

Guttorm Ringstad Opshaug; Per Enge

34

A System-On-Chip (SOC) platform to integrated Inertial Navigation Systems & GPS  

Microsoft Academic Search

Currently there are quite works investigate the inertial measurement unit (IMU) and the Global Position System (GPS) fusion. The majority are implemented on personal computers, due to the high computational cost. However, nowadays there are system on chip (SOC) platforms with a lot of resources capable of the integration with GPS\\/IMS, providing a high performance, variety of peripherals, ease communication

Alex Garcia-Quinchia; Yi Guo; E. Martin; C. Ferrer

2009-01-01

35

A step toward GPS\\/INS personal navigation systems: real-time assessment of gait by foot inertial sensing  

Microsoft Academic Search

In this paper, we develop a system for which applications in the field of personal navigation are planned. In the current version, the system embodies a Global Positioning System (GPS) receiver and an inertial measurement unit (IMU), composed of two dual-axis accelerometers and one single-axis gyro. The IMU is positioned at a subject's foot instep, and it is intended to

Filippo Cavallo; Angelo M. Sabatini; Vincenzo Genovese

2005-01-01

36

Vision coupled GPS\\/INS scheme for helicopter navigation  

Microsoft Academic Search

This paper presents a framework for a GPS\\/INS\\/vision-based helicopter navigation system. The conventional GPS\\/INS algorithm\\u000a has weak points such as GPS blockage and jamming, while the helicopter is a speedy and highly dynamic vehicle that may easily\\u000a lose a GPS signal. A vision sensor is not affected by signal jamming, and the navigation error of such a system does not

JaeHyung Kim; Joon Lyou; HwyKuen Kwak

2010-01-01

37

Design and flight test of a differential GPS/inertial navigation system for approach/landing guidance  

NASA Technical Reports Server (NTRS)

NASA-Langley has conducted a flight test program evaluating a differential GPS/inertial navigation system's (DGPS/INS) utility as an approach/landing aid. The DGPS/INS airborne and ground components are based on off-the-shelf transport aircraft avionics, namely a global positioning/inertial reference unit (GPIRU) and two GPS sensor units (GPSSUs). Systematic GPS errors are measured by the ground GPSSU and transmitted to the aircraft GPIRU, allowing the errors to be eliminated or greatly reduced in the airborne equipment. Over 120 landings were flown; 36 of these were fully automatic DGPS/INS landings.

Vallot, Lawrence; Snyder, Scott; Schipper, Brian; Parker, Nigel; Spitzer, Cary

1991-01-01

38

Definition study of land/sea civil user navigational location monitoring systems for NAVSTAR GPS: User requirements and systems concepts  

NASA Technical Reports Server (NTRS)

A low-cost GPS civil-user mobile terminal whose purchase cost is substantially an order of magnitude less than estimates for the military counterpart is considered with focus on ground station requirements for position monitoring of civil users requiring this capability and the civil user navigation and location-monitoring requirements. Existing survey literature was examined to ascertain the potential users of a low-cost NAVSTAR receiver and to estimate their number, function, and accuracy requirements. System concepts are defined for low cost user equipments for in-situ navigation and the retransmission of low data rate positioning data via a geostationary satellite to a central computing facility.

Devito, D. M.

1981-01-01

39

ION GNSS 2006, Fort Worth TX, 26-29 September 2006 1/14 Integrated GPS/INS System for Pedestrian Navigation in a  

E-print Network

research is focused on integrated IMU/GPS navigation systems for pedestrian and vehicular navigation. Dr for precise aircraft positioning. Dr. Cannon is a Past President of the Institute of Navigation evaluates the performance of a shoe/foot mounted inertial system for pedestrian navigation application. Two

Calgary, University of

40

GPS Navigation for Outdoor and Indoor Environments  

E-print Network

of this would matter. #12;i ABSTRACT The Global Positioning System (GPS) is an accurate positioning system..................................................................................................... 1 2 GLOBAL POSITIONING SYSTEM OVERVIEW .............................................. 2 3 GPS

Abidi, Mongi A.

41

76 FR 50808 - Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...The Director, Aircraft Certification...Airborne Supplemental Navigation Sensors for Global Positioning System Equipment Using Aircraft-Based Augmentation...ground- based systems (i.e., TSO-C129a...TSO-C145c, Airborne Navigation Sensors...

2011-08-16

42

An Investigation of Architectures For Integration Of Stand-Alone INS And GPS Navigation Systems.  

E-print Network

??Inertial navigation systems (INSs) have the well-known advantages of being self-contained, weatherproof, jam-proof, and non-self-revealing while providing stable navigation information with little high-frequency noise. However,… (more)

Dikshit, Veena G

2006-01-01

43

Attitude determination GPS\\/INS integrated navigation system with FDI algorithm for a UAV  

Microsoft Academic Search

Recently an unmanned aerial vehicle (UAV) has been widely used for military and civil applications. The role of a navigation\\u000a system in the UAV is to provide navigation data to the flight control computer (FCC) for guidance and control. Since performance\\u000a of the FCC is highly reliant on the navigation data, a fault in the navigation system may lead to

Sang Heon Oh; Dong-Hwan Hwang; Sang Jeong Lee; Se Hwan Kim

2005-01-01

44

Economics of Lightbar and Auto-Guidance GPS Navigation Technologies  

Microsoft Academic Search

To address the economic feasibility of Auto-Guidance and lightbar global positioning system (GPS) navigation technologies, a linear programming model was formulated using data from U.S. Corn Belt farms. Five scenarios were compared: (i) a baseline scenario with foam, disk or other visual marker reference, (ii) lightbar navigation with basic GPS availability (+\\/-3 dm accuracy), (iii) lightbar with satellite subscription correction

T. Griffin; D. Lambert; J. Lowenberg-DeBoer

45

Application of GPS navigation to space flight  

Microsoft Academic Search

The NASA Johnson Space Center (JSC) initiated GPS navigation projects for the space shuttle, International Space Station (ISS) and the X-38 (prototype crew return vehicle, or CRV) in the 1990s. While application of GPS technology to the shuttle and the ISS was successful, far more technical difficulties were encountered than were originally anticipated, and many lessons were learned. GPS receivers

J. L. Goodman

2005-01-01

46

Multiple mobile robot navigation using the indoor global positioning system (iGPS)  

Microsoft Academic Search

We propose a practical method of multiple mobile robot navigation aimed at the realization of service robots that deliver letters, parcels and documents in an office building. For robust execution of delivery tasks by mobile robots, navigation is important, and localization of robots is a key function for designing robust navigation. We developed a global positioning system for indoor mobile

Yoshiro HADA; Kunikatsu TAKASE

2001-01-01

47

Position, Navigation, and Timing: GPS Scientific Applications  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the development and deployment of the Global Positioning System (GPS). This presentation also includes measuring space and time, GPS as a tool for science, development of high precision JPL GPS receivers, and technology and applications developments.

Neilan, Ruth E.

2008-01-01

48

Evaluation of the impact of ionospheric disturbances on air navigation augmentation system using multi-point GPS receivers  

NASA Astrophysics Data System (ADS)

In recent years, GPS has been utilized for navigation system for airplanes. Propagation delays in the ionosphere due to total electron content (TEC) between GPS satellite and receiver cause large positioning errors. In precision measurement using GPS, the ionospheric delay correction is generally conducted using both GPS L1 and L2 frequencies. However, L2 frequency is not internationally accepted as air navigation band, so it is not available for positioning directly in air navigation. In air navigation, not only positioning accuracy but safety is important, so augmentation systems are required to ensure the safety. Augmentation systems such as the satellite-based augmentation system (SBAS) or the ground-based augmentation system (GBAS) are being developed and some of them are already in operation. GBAS is available in a relatively narrow area around airports. In general, it corrects for the combined effects of multiple sources of positioning errors simultaneously, including satellite clock and orbital information errors, ionospheric delay errors, and tropospheric delay errors, using the differential corrections broadcast by GBAS ground station. However, if the spatial ionospheric delay gradient exists in the area, correction errors remain even after correction by GBAS. It must be a threat to GBAS. In this study, we use the GPS data provided by the Geographical Survey Institute in Japan. From the GPS data, TEC is obtained every 30 seconds. We select 4 observation points from 24.4 to 35.6 degrees north latitude in Japan, and analyze TEC data of these points from 2001 to 2011. Then we reveal dependences of Rate of TEC change Index (ROTI) on latitude, season, and solar activity statistically. ROTI is the root-mean-square deviation of time subtraction of TEC within 5 minutes. In the result, it is the midnight of the spring and the summer of the solar maximum in the point of 26.4 degrees north latitude that the value of ROTI becomes the largest. We think it is caused by plasma bubbles, and the maximum value of ROTI is about 6 TECU/min. Since it is thought that ROTI is an index representing the spatial ionospheric delay gradient, we can evaluate the effect of spatial ionospheric delay gradient to GBAS. In addition, we will discuss azimuth angle dependence of ROTI. We have found that ROTI tends to be high when the GPS satellites are seen westward. Initial analysis results in Indonesia show a similar feature. This feature could arise from the westward tilt of the plasma bubbles with altitude. More detailed results will be reported in this presentation.

Omatsu, N.; Otsuka, Y.; Shiokawa, K.; Saito, S.

2013-12-01

49

High rate time-space-position-information for high dynamic GPS integrated navigation systems  

Microsoft Academic Search

The 746 Test Squadron (746 TS) has developed and implemented a high accuracy, high rate integrated Differential Global Positioning System\\/Inertial Navigation System (DGPS\\/INS) Time, Space, and Position Information (TSPI) truth reference to verify aircraft navigation system performance during flight tests. Specifically, the 746 TS participated in a fighter aircraft program. The 746 TSs unique truth reference system exploits the low

B. J. Bohenek; D. A. Ruff; J. F. Raquet

1996-01-01

50

Abstract--There is an increasing demand for use of the Global Positioning System (GPS) to navigate or track objects in the  

E-print Network

Abstract--There is an increasing demand for use of the Global Positioning System (GPS) to navigate--Forest, Global Positioning System, Image processing, Otsu' algorithm I. INTRODUCTION here is an increasing demand for use of the Global Positioning System (GPS) in the forest environment. For example, tree harvesters

Washington at Seattle, University of

51

Shuttle Global Positioning System (GPS) design study  

NASA Technical Reports Server (NTRS)

The effects of oscillator noise on Shuttle Global Positioning System (GPS) receiver performance, GPS navigation system self-test, GPS ground transmitter design to augment shuttle navigation, the effect of ionospheric delay modelling on GPS receiver design, and GPS receiver tracking of Shuttle transient maneuvers were investigated.

Nilsen, P. W.

1979-01-01

52

Evaluating the velocity accuracy of an integrated GPS/INS system: Flight test results. [Global positioning system/inertial navigation systems (GPS/INS)  

SciTech Connect

Verifying the velocity accuracy of a GPS receiver or an integrated GPS/INS system in a dynamic environment is a difficult proposition when many of the commonly used reference systems have velocity uncertainities of the same order of magnitude or greater than the GPS system. The results of flight tests aboard an aircraft in which multiple reference systems simultaneously collected data to evaluate the accuracy of an integrated GPS/INS system are reported. Emphasis is placed on obtaining high accuracy estimates of the velocity error of the integrated system in order to verify that velocity accuracy is maintained during both linear and circular trajectories. Three different reference systems operating in parallel during flight tests are used to independently determine the position and velocity of an aircraft in flight. They are a transponder/interrogator ranging system, a laser tracker, and GPS carrier phase processing. Results obtained from these reference systems are compared against each other and against an integrated real time differential based GPS/INS system to arrive at a set of conclusions about the accuracy of the integrated system.

Owen, T.E.; Wardlaw, R.

1991-01-01

53

An Integrated Navigation System using GPS Carrier Phase for Real-Time Airborne Synthetic Aperture Radar (SAR)  

SciTech Connect

A Synthetic Aperture Radar (SAR) requires accu- rate measurement of the motion of the imaging plat- form to produce well-focused images with minimal absolute position error. The motion measurement (MoMeas) system consists of a inertial measurement unit (IMU) and a P-code GPS receiver that outputs corrected ephemeris, L1 & L2 pseudoranges, and L1 & L2 carrier phase measurements. The unknown initial carrier phase biases to the GPS satellites are modeled as states in an extended Kalman filter and the resulting integrated navigation solution has po- sition errors that change slowly with time. Position error drifts less than 1- cm/sec have been measured from the SAR imagery for various length apertures.

Fellerhoff, J. Rick; Kim, Theodore J.; Kohler, Stewart M.

1999-06-24

54

Lessons learned from C-141C GPS enhanced navigation system (GPSENS) developmental flight test  

Microsoft Academic Search

This paper highlights some lessons learned in the developmental testing of the C-141 Global Positioning System Enhanced Navigation System (GPSENS) avionics upgrade. The authors planned and executed the flight tests of the GPSENS systems and learned many valuable lessons about retrofitting modern avionics into older aircraft. They found that commercial off the shelf acquisition strategies seemed much more suitable for

J. S. Seo; C. C. McCann

1999-01-01

55

Ionospheric specification algorithms for precise GPS-based aircraft navigation  

Microsoft Academic Search

The Federal Aviation Administration (FAA) is implementing an aircraft navigation scheme for the United States using the Global Positioning System (GPS) L1 signal (1575.42 MHz). To achieve position accuracies of a few meters, sufficient to allow precision airfield approaches, it will be necessary to broadcast corrections to the direct GPS signal. A significant component of these corrections is the delay

I. L. Harris; A. J. Mannucci; B. A. Iijima; U. J. Lindqwister; D. Muna; X. Pi; B. D. Wilson

2001-01-01

56

GPS Receiver Manually-Entered Position Offsets May Cause Safety Hazard when Interconnected to Navigation Devices It has come to the attention of the U.S. Coast Guard that certain Global Positioning System (GPS)  

E-print Network

receivers do not provide a proper indication to other connected equipment when manually-entered position offsets are entered into the GPS receiver. Even a small offset could result in danger of collision or other navigation safety hazard when the receiver is interconnected to devices such as an automatic identification system (AIS), Electronic Chart Display and Information System (ECDIS), integrated navigation systems (INS) or track control system (TCS). The problem is caused by an error in the NMEA 0183/IEC 61162 data interface Datum Reference (“DTM”) “local datum ” field. Navigation systems interconnected to the GPS receiver use this field to determine whether the position received is referenced to World Geodetic System 84 (WGS84) or something different. AIS equipment, for example, disregards external position information for reasons of safety if the “local datum ” field does not indicate WGS84. As a result, equipment that is interfaced to GPS receivers having this problem would act as if the position were referenced to the WGS84 datum, when in fact the position differs from the WGS84 datum by the manual offsets entered by the vessel’s crew or captain. The problem can be identified if own ship position displayed on an AIS changes in proportion to manually-entered offsets entered into the GPS receiver interconnected to the AIS. The GPS is operating correctly in such a situation if the AIS reverts to its integral GPS and disregards the manually-entered offsets sent from the externally-connected GPS. GPS Receivers identified having this problem:

Furuno Gp; Furuno Gp

57

Autonomous GPS/INS navigation experiment for Space Transfer Vehicle  

NASA Technical Reports Server (NTRS)

An experiment to validate the concept of developing an autonomous integrated spacecraft navigation system using on board Global Positioning System (GPS) and Inertial Navigation System (INS) measurements is described. The feasibility of integrating GPS measurements with INS measurements to provide a total improvement in spacecraft navigation performance, i.e. improvement in position, velocity and attitude information, was previously demonstrated. An important aspect of this research is the automatic real time reconfiguration capability of the system designed to respond to changes in a spacecraft mission under the control of an expert system.

Upadhyay, Triveni N.; Cotterill, Stephen; Deaton, A. W.

1993-01-01

58

Non-GPS navigation with the personal dead-reckoning system  

NASA Astrophysics Data System (ADS)

This paper introduces a positioning system for walking persons, called "Personal Dead-reckoning" (PDR) system. The PDR system does not require GPS, beacons, or landmarks. The system is therefore useful in GPS-denied environments, such as inside buildings, tunnels, or dense forests. Potential users of the system are military and security personnel as well as emergency responders. The PDR system uses a small 6-DOF inertial measurement unit (IMU) attached to the user's boot. The IMU provides rate-of-rotation and acceleration measurements that are used in real-time to estimate the location of the user relative to a known starting point. In order to reduce the most significant errors of this IMU-based system-caused by the bias drift of the accelerometers-we implemented a technique known as "Zero Velocity Update" (ZUPT). With the ZUPT technique and related signal processing algorithms, typical errors of our system are about 2% of distance traveled. This typical PDR system error is largely independent of the gait or speed of the user. When walking continuously for several minutes, the error increases gradually beyond 2%. The PDR system works in both 2-dimensional (2-D) and 3-D environments, although errors in Z-direction are usually larger than 2% of distance traveled. Earlier versions of our system used an impractically large IMU. In the most recent version we implemented a much smaller IMU. This paper discussed specific problems of this small IMU, our measures for eliminating these problems, and our first experimental results with the small IMU under different conditions.

Ojeda, Lauro; Borenstein, Johann

2007-04-01

59

Operational Use of GPS Navigation for Space Shuttle Entry  

NASA Technical Reports Server (NTRS)

The STS-118 flight of the Space Shuttle Endeavour was the first shuttle mission flown with three Global Positioning System (GPS) receivers in place of the three legacy Tactical Air Navigation (TACAN) units. This marked the conclusion of a 15 year effort involving procurement, missionization, integration, and flight testing of a GPS receiver and a parallel effort to formulate and implement shuttle computer software changes to support GPS. The use of GPS data from a single receiver in parallel with TACAN during entry was successfully demonstrated by the orbiters Discovery and Atlantis during four shuttle missions in 2006 and 2007. This provided the confidence needed before flying the first all GPS, no TACAN flight with Endeavour. A significant number of lessons were learned concerning the integration of a software intensive navigation unit into a legacy avionics system. These lessons have been taken into consideration during vehicle design by other flight programs, including the vehicle that will replace the Space Shuttle, Orion.

Goodman, John L.; Propst, Carolyn A.

2008-01-01

60

A technique for the current control of availability of navigation definitions of GPS\\/GLONASS users based on data of the wide area differential system  

Microsoft Academic Search

Atechnique for the on-line monitoring of the availability of navigation support of objects has been considered using the wide\\u000a area differential subsystem of GPS\\/GLONASS satellite radio navigation systems. This technique is based on estimating the total\\u000a probability of solving the problem of navigation determinations with the specified level of accuracy and continuity. The technique\\u000a developed can be used for enhancing

V. V. Demyanov

2009-01-01

61

Loosely Coupled GPS-Aided Inertial Navigation System for Range Safety  

NASA Technical Reports Server (NTRS)

The Autonomous Flight Safety System (AFSS) aims to replace the human element of range safety operations, as well as reduce reliance on expensive, downrange assets for launches of expendable launch vehicles (ELVs). The system consists of multiple navigation sensors and flight computers that provide a highly reliable platform. It is designed to ensure that single-event failures in a flight computer or sensor will not bring down the whole system. The flight computer uses a rules-based structure derived from range safety requirements to make decisions whether or not to destroy the rocket.

Heatwole, Scott; Lanzi, Raymond J.

2010-01-01

62

Satellite Navigation Systems  

NSDL National Science Digital Library

The Global Positioning System (GPS) has been in operation for several years, and its use is continually rising. GPS is the main satellite navigation system developed by the United States. There are countless applications of this technology, and numerous international efforts are currently underway.The Topcon Positioning Systems company provides an excellent introduction to GPS technology in its online book (1). The first couple chapters describe the evolution of GPS and its fundamentals, and the remaining material focuses on some specific issues. A more advanced tutorial is given through the IBM Web site (2). A brief, free registration is required to view it, and some familiarity with Java is recommended. The European Space Agency provides this page about satellite navigation (3), which describes, among other things, Galileo. This is not the astronomer; Galileo is Europe's version of GPS, scheduled for completion in 2008. Another system, developed by Russia, is detailed on the Space and Technology Web site (4). The short summary describes the 20-year history of the Global Navigation Satellite System (GLONASS), as well as upgrades that are in progress. Differential GPS, a service that is more accurate than standard GPS in areas with poor coverage, is operated by the US Coast Guard Navigation Center (5). Some information about the status of nationwide DGPS expansion is given. Several research and development projects, technology highlights, and GPS implementations are covered on the UNAVCO home page (6). The facility primarily fosters work to expand the applications of satellite navigation. With the wave of kidnapping cases reported across the country, a novel use of GPS is being marketed to keep track of children (7). These portable devices can be worn on the wrist, like a watch, so parents can always know where their kids are. Another news story describes the use of GPS in mining operations (8). The technology allows operators of huge three-story dump trucks to detect obstacles and maneuver the vehicle with only limited visibility.

Leske, Cavin.

2002-01-01

63

Spacecraft orbit determination using GPS navigation solutions  

Microsoft Academic Search

The orbit determination using the GPS navigation solutions for the KOMPSAT-1 spacecraft has been studied. The Cowell method of special perturbation theories was employed to develop a precision orbit propagation, and the perturbations due to geopotential, the gravity of the Sun and the Moon, solid Earth tides, ocean tides, the Earth's dynamic polar motion, solar radiation pressure, and atmospheric drag

Jae-Cheol Yoon; Byoung-Sun Lee; Kyu-Hong Choi

2000-01-01

64

Ready To Navigate: Classroom GPS Applications.  

ERIC Educational Resources Information Center

Discusses the potential contribution of GPS and related Geographic Information Systems (GIS) technology to education. Provides resources for teachers to plan a lesson on exploring with the help of a GPS device in order to increase students' awareness of their surroundings and broaden understanding of their place in the world. (KHR)

Lucking, Robert A.; Christmann, Edwin P.

2002-01-01

65

Study on a novel marine INS\\/GPS integrated navigation technology  

Microsoft Academic Search

When designing Kalman filter for INS\\/GPS, usually position and velocity are chosen as the measuring variables. With the development of GPS attitude determination, GPS has already been able to measure the carrier's attitudes. So attitude can be augmented as the measuring variables. In this paper a new INS\\/GPS integrated navigation System is designed, in which position, velocity and attitude are

Yang Yanjuan; Weifeng Tian; Zhihua Jin

2002-01-01

66

GPS-aided inertial technology and navigation-based photogrammetry for aerial mapping the San Andreas fault system  

USGS Publications Warehouse

Aerial mapping of the San Andreas Fault System can be realized more efficiently and rapidly without ground control and conventional aerotriangulation. This is achieved by the direct geopositioning of the exterior orientation of a digital imaging sensor by use of an integrated Global Positioning System (GPS) receiver and an Inertial Navigation System (INS). A crucial issue to this particular type of aerial mapping is the accuracy, scale, consistency, and speed achievable by such a system. To address these questions, an Applanix Digital Sensor System (DSS) was used to examine its potential for near real-time mapping. Large segments of vegetation along the San Andreas and Cucamonga faults near the foothills of the San Bernardino and San Gabriel Mountains were burned to the ground in the California wildfires of October-November 2003. A 175 km corridor through what once was a thickly vegetated and hidden fault surface was chosen for this study. Both faults pose a major hazard to the greater Los Angeles metropolitan area and a near real-time mapping system could provide information vital to a post-disaster response.

Sanchez, Richard D.; Hudnut, Kenneth W.

2004-01-01

67

GPS Auto-Navigation Design for Unmanned Air Vehicles  

NASA Technical Reports Server (NTRS)

A GPS auto-navigation system is designed for Unmanned Air Vehicles. The objective is to enable the air vehicle to be used as a test-bed for novel flow control concepts. The navigation system uses pre-programmed GPS waypoints. The actual GPS position, heading, and velocity are collected by the flight computer, a PC104 system running in Real-Time Linux, and compared with the desired waypoint. The navigator then determines the necessity of a heading correction and outputs the correction in the form of a commanded bank angle, for a level coordinated turn, to the controller system. This controller system consists of 5 controller! (pitch rate PID, yaw damper, bank angle PID, velocity hold, and altitude hold) designed for a closed loop non-linear aircraft model with linear aerodynamic coefficients. The ability and accuracy of using GPS data, is validated by a GPS flight. The autopilots are also validated in flight. The autopilot unit flight validations show that the designed autopilots function as designed. The aircraft model, generated on Matlab SIMULINK is also enhanced by the flight data to accurately represent the actual aircraft.

Nilsson, Caroline C. A.; Heinzen, Stearns N.; Hall, Charles E., Jr.; Chokani, Ndaona

2003-01-01

68

GPS - Global Positioning System. Theory and practice  

Microsoft Academic Search

This book shows in comprehensive manner how the Global Positioning System (GPS) works. The use of GPS for precise measurements (i.e. surveying) is treated as well as navigation and attitude determination. The basic mathematical models for various modes of GPS operations and detailed explanation of the practical use of GPS are developed precisely in this book. Additionally, the text shows

B. Hofmann-Wellenhof; H. Lichtenegger; J. Collins

1997-01-01

69

Selection of the Filtering Correction Cycle to Improve INS\\/GPS Integrated Navigation Accuracy  

Microsoft Academic Search

In order to improve the accuracy of INS\\/GPS integrated navigation system, especially in such a case when it works from the integrated navigation into the pure inertial navigation, the schemes of the Kalman filter correction cycle is proposed. Based on detail analysis on the error rule of INS and the error feature of the GPS output signal from several flight-test

Guo Chuang; Zhao Guo-jun

2006-01-01

70

A relative navigation system for formation flight  

Microsoft Academic Search

A relative navigation system based on both the Inertial Navigation System (INS) and the Global Positioning System (GPS) is developed to support situational awareness during formation flight. The architecture of the system requires an INS\\/GPS integration across two aircraft via a data link. A fault-tolerant federated filter is used to estimate the relative INS errors based on relative GPS measurements

STEPHEN C. FELTER; N. E. Wu

1997-01-01

71

Integrated GPS\\/INS navigation system design for autonomous spacecraft rendezvous  

Microsoft Academic Search

The goal of the NASA Space Launch Initiative (SLI) program is to advance the technologies for the next generation reusable launch vehicle (RLV). The SLI program has identified automated rendezvous and docking as an area requiring further research and development. Currently, the Space Shuttle uses a partially manual system for rendezvous, but a fully automated system could be safer and

David Edward Gaylor

2003-01-01

72

Navigation Systems -Nolan, Chap 2  

E-print Network

1 Navigation Systems - Approach Nolan, Chap 2 #12;2 Approach Navigation Visual Approach Procedures · visibility > 1nm Initial Intermediate Final ·Precision ·Non-precision Missed Approach Lighting Runway ·Inner ILS/DMETerminal VOR GPS ·WAAS ·LAAS Electronic Navigation #12;3 Visual Approach Procedures · Pilot

73

ICD-GPS-20OB-PR Navstar GPS Space Segment/Navigation User Interfaces (Public Release Version).  

National Technical Information Service (NTIS)

This Interface Control Document (ICD) defines the functional characteristics required to exist to assure compatibility between the Space Segment (SS) of the Global Positioning System and the Navigation User Segment (US) of the GPS. The exception is that t...

P. Fyfe, K. Kovach

1991-01-01

74

Decentralised approach to UAV navigation: without the use of GPS and preloaded maps  

E-print Network

: inertial (or dead-reckoning) based navigation, and reference (or absolute) based navigation. An Inertial Navigation System (INS) makes use of an Inertial Measurement Unit (IMU) to sense the vehicle's rotation rateDecentralised approach to UAV navigation: without the use of GPS and preloaded maps Jonghyuk Kim1

Kim, Jonghyuk "Jon"

75

GPS Navigation for the Magnetospheric Multi-Scale Mission  

NASA Technical Reports Server (NTRS)

In 2014. NASA is scheduled to launch the Magnetospheric Multiscale Mission (MMS), a four-satellite formation designed to monitor fluctuations in the Earth's magnetosphere. This mission has two planned phases with different orbits (1? x 12Re and 1.2 x 25Re) to allow for varying science regions of interest. To minimize ground resources and to mitigate the probability of collisions between formation members, an on-board orbit determination system consisting of a Global Positioning System (GPS) receiver and crosslink transceiver was desired. Candidate sensors would be required to acquire GPS signals both below and above the constellation while spinning at three revolutions-per-minute (RPM) and exchanging state and science information among the constellation. The Intersatellite Ranging and Alarm System (IRAS), developed by Goddard Space Flight Center (GSFC) was selected to meet this challenge. IRAS leverages the eight years of development GSFC has invested in the Navigator GPS receiver and its spacecraft communication expertise, culminating in a sensor capable of absolute and relative navigation as well as intersatellite communication. The Navigator is a state-of-the-art receiver designed to acquire and track weak GPS signals down to -147dBm. This innovation allows the receiver to track both the main lobe and the much weaker side lobe signals. The Navigator's four antenna inputs and 24 tracking channels, together with customized hardware and software, allow it to seamlessly maintain visibility while rotating. Additionally, an extended Kalman filter provides autonomous, near real-time, absolute state and time estimates. The Navigator made its maiden voyage on the Space Shuttle during the Hubble Servicing Mission, and is scheduled to fly on MMS as well as the Global Precipitation Measurement Mission (GPM). Additionally, Navigator's acquisition engine will be featured in the receiver being developed for the Orion vehicle. The crosslink transceiver is a 1/4 Watt transmitter utilizing a TDMA schedule to distribute a science quality message to all constellation members every ten seconds. Additionally the system generates one-way range measurements between formation members which is used as input to the Kalman filter. In preparation for the MMS Preliminary Design Review (PDR), the Navigator was required to pass a series of Technology Readiness Level (TRL) tests to earn the necessary TRL-6 classification. The TRL-6 level is achieved by demonstrating a prototype unit in a relevant end-to-end environment. The IRAS unit was able to meet all requirements during the testing phase, and has thus been TRL-6 qualified

Bamford, William; Mitchell, Jason; Southward, Michael; Baldwin, Philip; Winternitz, Luke; Heckler, Gregory; Kurichh, Rishi; Sirotzky, Steve

2009-01-01

76

High Sensitivity GPS Velocity Updates For Personal Indoor Navigation Using Inertial  

E-print Network

extensively on the integration of GPS and inertial navigation systems for precise aircraft positioning. Dr Systems M.G. Petovello, O. Mezentsev, G. Lachapelle, M.E. Cannon Position, Location and Navigation (PLAN to update a tactical-grade inertial navigation system. The advantage of this approach is that Doppler

Calgary, University of

77

Using GPS and GPS/INS Systems to Assess Relative Antenna Motion Onboard an Aircraft  

E-print Network

navigation systems for precise aircraft positioning. Dr. Cannon is a Past President of the ION. ABSTRACTUsing GPS and GPS/INS Systems to Assess Relative Antenna Motion Onboard an Aircraft Carrier for Shipboard Relative GPS M.G. Petovello, G. Lachapelle and M.E. Cannon Position, Location And Navigation (PLAN

Calgary, University of

78

Space Navigation with Digital Beam Steering GPS Receiver Technology  

Microsoft Academic Search

Space-based GPS technology presents several significant challenges over Earth based systems. These include visibility issues for rotating platforms, and tracking of GPS satellites from spacecraft that are in higher orbits than the GPS. Kinematic relative position in orbit also presents challenges in resolving carrier phase ambiguities in real time. NAVSYS has developed a digital GPS receiver that makes use of

Kenn Gold; Randy Silva; Alison Brown

79

Passive GPS-Free Navigation for Small UAVs Jack Langelaan  

E-print Network

-free navigation of a small Unmanned Aerial Vehicle with a minimal sensor suite (limited to an inertial measurement objects on the ground we can obtain a navigation solution. Fusing inertial measurements with bearingsPassive GPS-Free Navigation for Small UAVs Jack Langelaan Steve Rock Department of Aeronautics

Langelaan, Jack W.

80

A Comparative Study of Kalman Filter Implementations for Relative GPS Navigation  

E-print Network

stations to determine the location of a vessel or aircraft. A disadvantage to long range navigation is its limited coverage. B. Global Position System In the 1950s, the space race that ensued between the United States and former So- viet Union paved the way... and three GPS satellites located approximately 120 apart along the horizon line of the antenna eld of view [5]. GPS satellites are commonly used for ground based and aircraft navigation. The system has also been used for space applications. GPS navigation...

Fritz, Matthew Peyton

2011-02-22

81

Sigma-Point Kalman Filtering for Integrated GPS and Inertial Navigation  

E-print Network

Sigma-Point Kalman Filtering for Integrated GPS and Inertial Navigation John L. Crassidis in position/attitude estimation problems. The filter formulation is based on standard inertial navigation vehicle. An Inertial Navigation System (INS) is best described in the Preface section of the excellent

Crassidis, John L.

82

Sensor data fusion for inertial navigation of trains in GPS-dark areas  

Microsoft Academic Search

The motivation of the presented work is to develop a robust navigation system for accurate localization of trains on railway tracks in the cases where the GPS-based navigation is not temporally available. As the final solution of the train locator naturally takes into consideration the satellite-based navigation, the satellite signal needs not to be available all along the railway. The

R. Mazl; L. Preucil

2003-01-01

83

Inertial navigation aided with GPS information  

Microsoft Academic Search

This paper presents a dynamic alignment algorithm for a six-degree of freedom inertial unit. A differential GPS is used as external sensor. It provides decorrelated range position and Doppler velocity information. A simplified error model valid for a local area is also presented. An indirect Kalman filter approach is used to fuse high frequency inertial information with low frequency GPS

E. Nebot; S. Sukkarieh; H. Durrant-Whyte

1997-01-01

84

Global Positioning System Tutorial: All About GPS  

NSDL National Science Digital Library

The Global Positioning System (GPS) is a very popular and useful tool, whether you're navigating on a long hike or just driving through an unfamiliar town. A good tutorial that introduces the basics of the technology is found on the Web site of a leading GPS company, Trimble. It starts by describing the underlying concepts of GPS and how it compares to other positioning systems. Then, the principle of satellite triangulation is explained with as little technical jargon as possible. A large section of the tutorial covers differential GPS, a developing technology with profound implications. Lastly, some applications that use GPS are mentioned, and a glossary clarifies a few special terms.

2007-03-06

85

Proceedings of NTM 2004 Conference (Session E3), San Diego, CA, January 26-28, The Institute of Navigation. 1 Kinematic Azimuth Alignment of INS using GPS  

E-print Network

is on the integration of GPS with medium accuracy inertial navigation systems. Dr. M. Elizabeth Cannon is Professor as the integration of GPS with inertial navigation systems for wide variety of applications. She is a Past President of the Institute of Navigation. ABSTRACT The combination of the Global Positioning System (GPS) and an Inertial

Calgary, University of

86

Designing a Remote Navigation System  

Microsoft Academic Search

This project involves the design and implementation of a global electronic tracking system intended for use by trans-oceanic vessels, using the technology of the U.S. Government's Global Positioning System (GPS) and a wireless connection to a networked computer.\\u000aTraditional navigation skills are being replaced with highly accurate electronics. GPS receivers, computers, and mobile communication are becoming common among both recreational

Jared P. Lazzaro

2000-01-01

87

GPS and UWB for indoor navigation Guttorm Ringstad Opshaug and Per Enge  

E-print Network

to multipath that is less than one chip width away from a direct path ray. In the case of GPS CGPS and UWB for indoor navigation Guttorm Ringstad Opshaug and Per Enge Department of Aeronautics would make such an endeavor worthwhile. Some server-based GPS systems, like SnapTrack, already claim

Stanford University

88

A Regional Tropospheric Delay Model for the Indian Subcontinent with Application to GPS Based Aircraft Navigation  

Microsoft Academic Search

Application of Global Positioning System (GPS) in satellite-based navigation essentially requires a priori knowledge of the tropospheric refraction effect of GPS signal. The tropospheric delay estimated by ray tracing through the earth's atmosphere employing appropriate altitude profile of refractivity, is modeled in terms of measurable surface atmospheric parameters such as pressure, temperature, humidity as well as columnar water vapor for

Korak Saha; Suresh Raju C; Krishnaswamy Parameswaran

2008-01-01

89

Long-term evolution of navigation satellite orbits: GPS\\/GLONASS\\/GALILEO  

Microsoft Academic Search

A recent study was performed to examine whether long-term growth in the eccentricity evolution exists for the disposal orbits of navigation satellite systems such as GPS, GLONASS, and GALILEO. Previous studies examined the orbit stability for GPS Block II satellites. The orbits of the non-operational GPS Block I satellites are included in this study because they are at 63.4° inclination,

C. C. Chao; R. A Gick

2004-01-01

90

A LEO Satellite Navigation Algorithm Based on GPS and Magnetometer Data  

NASA Technical Reports Server (NTRS)

The Global Positioning System (GPS) has become a standard method for low cost onboard satellite orbit determination. The use of a GPS receiver as an attitude and rate sensor has also been developed in the recent past. Additionally, focus has been given to attitude and orbit estimation using the magnetometer, a low cost, reliable sensor. Combining measurements from both GPS and a magnetometer can provide a robust navigation system that takes advantage of the estimation qualities of both measurements. Ultimately a low cost, accurate navigation system can result, potentially eliminating the need for more costly sensors, including gyroscopes.

Deutschmann, Julie; Bar-Itzhack, Itzhack; Harman, Rick; Bauer, Frank H. (Technical Monitor)

2000-01-01

91

Perspective\\/navigation-The Global Positioning System  

Microsoft Academic Search

A brief history of navigation is given, highlighting the needs that led ultimately to the development of 3-D satellite based navigation. The evolution of Navstar, commonly known as GPS (Global Positioning System), is traced from its initial conception in 1960. The use of bandwidth compression to overcome the SNR problem is discussed. An explanation of how the GPS works is

1993-01-01

92

Institute of Navigation GPS-99/Nashville/September 13-17, 1999 1 PSEUDOLITE-BASED INVERTED GPS  

E-print Network

Institute of Navigation GPS-99/Nashville/September 13-17, 1999 1 PSEUDOLITE-BASED INVERTED GPS at the University of Calgary. She has been involved with GPS research since 1984 and has published numerous papers on static and kinematic GPS positioning. She is also the author of several GPS related software programs. Dr

Calgary, University of

93

Integrating GIS and GPS to realise autonomous navigation of farm machinery  

Microsoft Academic Search

Path planning is a key technique to realise autonomous navigation of farm machines. Based on MapObjects, a Geographic Information System (GIS) for autonomous navigation was developed with Visual C++. A path search algorithm used to guide machines to track the desired path was designed. A Global Positioning System (GPS) was adopted in this algorithm to determine the current position of

Meng Xiangjian; Liu Gang

2007-01-01

94

A Leo Satellite Navigation Algorithm Based on GPS and Magnetometer Data  

NASA Technical Reports Server (NTRS)

The Global Positioning System (GPS) has become a standard method for low cost onboard satellite orbit determination. The use of a GPS receiver as an attitude and rate sensor has also been developed in the recent past. Additionally, focus has been given to attitude and orbit estimation using the magnetometer, a low cost, reliable sensor. Combining measurements from both GPS and a magnetometer can provide a robust navigation system that takes advantage of the estimation qualities of both measurements. Ultimately, a low cost, accurate navigation system can result, potentially eliminating the need for more costly sensors, including gyroscopes. This work presents the development of a technique to eliminate numerical differentiation of the GPS phase measurements and also compares the use of one versus two GPS satellites.

Deutschmann, Julie; Harman, Rick; Bar-Itzhack, Itzhack

2001-01-01

95

Abstract--There is an increasing demand for use of the Global Positioning System (GPS) to navigate or track objects in the  

E-print Network

1 Abstract--There is an increasing demand for use of the Global Positioning System (GPS--Forest, Global Positioning System, Image processing, Otsu' algorithm I. INTRODUCTION here is an increasing demand for use of the Global Positioning System (GPS) in the forest environment. For example, tree harvesters

Wang, Yinhai

96

A LEAPFROG NAVIGATION SYSTEM A DISSERTATION  

E-print Network

, leapfrogging assumes known initial positions of at least two currently stationary navigation units. Two or moreA LEAPFROG NAVIGATION SYSTEM A DISSERTATION SUBMITTED TO THE DEPARTMENT OF AERONAUTICS and places where conventional navigation systems, such as the Global Positioning System (GPS

Stanford University

97

Sole means navigation and integrity through hybrid Loran-C and NAVSTAR GPS  

NASA Technical Reports Server (NTRS)

A sole means navigation system does not only call for integrity, but also for coverage, reliability, availability and accuracy. Even though ground monitored GPS will provide integrity, availability is still not sufficient. One satellite outage can affect a large service area for several hours per day. The same holds for differential GPS; a total satellite outage cannot be corrected for. To obtain sufficient coverage, extra measurements are needed, either in the form of extra GPS satellites (expensive) or through redundant measurements from other systems. LORAN-C is available and will, hybridized with GPS, result in a system that has the potential to satisfy the requirements for a sole means navigation system for use in the continental United States. Assumptions are made about the qualification sole means, mainly based on current sole means systems such as VOR/DME. In order to allow for system design that will satisfy sole means requirements, it is recommended that a definition of a sole means navigation system be established. This definition must include requirements for availability, reliability, and integrity currently not specified. In addition to the definition of a sole means navigation system, certification requirements must be established for hybrid navigation systems. This will allow for design and production of a new generation of airborne navigation systems that will reduce overall system costs and simplify training procedures.

Vangraas, Frank

1990-01-01

98

GPS system simulation methodology  

NASA Technical Reports Server (NTRS)

The following topics are presented: background; Global Positioning System (GPS) methodology overview; the graphical user interface (GUI); current models; application to space nuclear power/propulsion; and interfacing requirements. The discussion is presented in vugraph form.

Ewing, Thomas F.

1993-01-01

99

GPS system simulation methodology  

NASA Astrophysics Data System (ADS)

The following topics are presented: background; Global Positioning System (GPS) methodology overview; the graphical user interface (GUI); current models; application to space nuclear power/propulsion; and interfacing requirements. The discussion is presented in vugraph form.

Ewing, Thomas F.

100

IMPROVING THE ATTITUDE ACCURACY OF A LOW COST MEMS\\/GPS INTEGRATED SYSTEM USING GPS HEADING SENSORS  

Microsoft Academic Search

Integrated GPS\\/INS systems provide an enhanced navigation system that has superior performance in comparison with either system operating in stand-alone mode as it can overcome each of their limitations. The high cost and government regulations prevent the wider inclusion of high quality IMUs to augment GPS as a commercialized navigation system in many navigation applications. The progress in MEMS technology

Y. W. Huang; C. Y. Li; H. W. Wu; H. W. Chang; H. W. Hu; K. W. Chiang

101

Navigation Systems -Enroute Nolan, Chap 2  

E-print Network

1 Navigation Systems - Enroute Nolan, Chap 2 #12;2 En-route Navigation Visual Flight Rules Pilotage ·MEA's ·MOCA's GPS WAAS LAAS INS NDB #12;3 Navigation · Guide aircraft from origin to destination/Dead-Reckoning Aircraft Instruments: ·Magnetic Compass/ ·Heading Indicator Aeronautic Charts Forecast Wind Instrument

102

GPS Navigation Results from the Low Power Transceiver CANDOS Experiment on STS-107  

NASA Technical Reports Server (NTRS)

This paper presents the Global Positioning System (GPS) navigation results from the Communications and Savigation Demonstration on Shuttle (CANDOS) experiment flown on STS- 107. The CAkDOS experiment consisted of the Low Power Transceiver (LPT) that hosted the GPS Enhanced Orbit Determination Experiment (GEODE) orbit determination software. All CANDOS test data were recovered during the mission using the LPT's Tracking and Data Relay Satellite System (TDRSS) uplinh'downlink communications capabilit! . An overview of the LPT's navigation software and the GPS experiment timeline is presented. In addition. this paper discusses GEODE performance results. including comparisons ibith the Best Estimate of Trajectory (BET). N.ASA Johnson Space Center (JSC) real-time ground navigation vectors. and post-processed solutions using the Goddard Trajectory Determination System (GTDS).

Haas, Lin; Massey, Chris; Baraban, Dmitri; Kelbel, David; Lee, Taesul; Long, Anne; Carpenter, J. Russell

2003-01-01

103

Multi-Flight-Phase GPS Navigation Filter Applications to Terrestrial Vehicle Navigation and Positioning  

NASA Technical Reports Server (NTRS)

A candidate onboard space navigation filter demonstrated excellent performance (less than 8 meter level RMS semi-major axis accuracy) in performing orbit determination of a low-Earth orbit Explorer satellite using single-frequency real GPS data. This performance is significantly better than predicted by other simulation studies using dual-frequency GPS data. The study results revealed the significance of two new modeling approaches evaluated in the work. One approach introduces a single-frequency ionospheric correction through pseudo-range and phase range averaging implementation. The other approach demonstrates a precise axis-dependent characterization of dynamic sample space uncertainty to compute a more accurate Kalman filter gain. Additionally, this navigation filter demonstrates a flexibility to accommodate both perturbational dynamic and observational biases required for multi-flight phase and inhomogeneous application environments. This paper reviews the potential application of these methods and the filter structure to terrestrial vehicle and positioning applications. Both the single-frequency ionospheric correction method and the axis-dependent state noise modeling approach offer valuable contributions in cost and accuracy improvements for terrestrial GPS receivers. With a modular design approach to either 'plug-in' or 'unplug' various force models, this multi-flight phase navigation filter design structure also provides a versatile GPS navigation software engine for both atmospheric and exo-atmospheric navigation or positioning use, thereby streamlining the flight phase or application-dependent software requirements. Thus, a standardized GPS navigation software engine that can reduce the development and maintenance cost of commercial GPS receivers is now possible.

Park, Young W.; Montez, Moises N.

1994-01-01

104

Development And Test of A Digitally Steered Antenna Array for The Navigator GPS Receiver  

NASA Technical Reports Server (NTRS)

Global Positioning System (GPS)-based navigation has become common for low-Earth orbit spacecraft as the signal environment is similar to that on the Earth s surface. The situation changes abruptly, however, for spacecraft whose orbital altitudes exceed that of the GPS constellation. Visibility is dramatically reduced and signals that are present may be very weak and more susceptible to interference. GPS receivers effective at these altitudes require increased sensitivity, which often requires a high-gain antenna. Pointing such an antenna can pose a challenge. One efficient approach to mitigate these problems is the use of a digitally steered antenna array. Such an antenna can optimally allocate gain toward desired signal sources and away from interferers. This paper presents preliminary results in the development and test of a digitally steered antenna array for the Navigator GPS research program at NASA s Goddard Space Flight Center. In particular, this paper highlights the development of an array and front-end electronics, the development and test of a real-time software GPS receiver, and implementation of three beamforming methods for combining the signals from the array. Additionally, this paper discusses the development of a GPS signal simulator which produces digital samples of the GPS L1C/A signals as they would be received by an arbitrary antenna array configuration. The simulator models transmitter and receiver dynamics, near-far and multipath interference, and has been a critical component in both the development and test of the GPS receiver. The GPS receiver system was tested with real and simulated GPS signals. Preliminary results show that performance improvement was achieved in both the weak signal and interference environments, matching analytical predictions. This paper summarizes our initial findings and discusses the advantages and limitations of the antenna array and the various beamforming methods.

Pinto, Heitor David; Valdez, Jennifer E.; Winternitz, Luke M. B.; Hassouneh, Munther A.; Price, Samuel R.

2012-01-01

105

Robust Real-Time Wide-Area Differential GPS Navigation  

NASA Technical Reports Server (NTRS)

The present invention provides a method and a device for providing superior differential GPS positioning data. The system includes a group of GPS receiving ground stations covering a wide area of the Earth's surface. Unlike other differential GPS systems wherein the known position of each ground station is used to geometrically compute an ephemeris for each GPS satellite. the present system utilizes real-time computation of satellite orbits based on GPS data received from fixed ground stations through a Kalman-type filter/smoother whose output adjusts a real-time orbital model. ne orbital model produces and outputs orbital corrections allowing satellite ephemerides to be known with considerable greater accuracy than from die GPS system broadcasts. The modeled orbits are propagated ahead in time and differenced with actual pseudorange data to compute clock offsets at rapid intervals to compensate for SA clock dither. The orbital and dock calculations are based on dual frequency GPS data which allow computation of estimated signal delay at each ionospheric point. These delay data are used in real-time to construct and update an ionospheric shell map of total electron content which is output as part of the orbital correction data. thereby allowing single frequency users to estimate ionospheric delay with an accuracy approaching that of dual frequency users.

Yunck, Thomas P. (Inventor); Bertiger, William I. (Inventor); Lichten, Stephen M. (Inventor); Mannucci, Anthony J. (Inventor); Muellerschoen, Ronald J. (Inventor); Wu, Sien-Chong (Inventor)

1998-01-01

106

Applications of Clocks to Space Navigation & "Planetary GPS"  

NASA Technical Reports Server (NTRS)

The ability to fly atomic clocks on GPS satellites has profoundly defined the capabilities and limitations of GPS in near-Earth applications. It is likely that future infrastructure for Lunar and Mars applications will be constrained by financial factors. The development of a low cost, small, high performance space clock -- or ultrahigh performance space clocks -- could revolutionize and drive the entire approach to GPS-like systems at the Moon (or Mars), and possibly even change the future of GPS at Earth. Many system trade studies are required. The performance of future GPS-like tracking systems at the Moon or Mars will depend critically on clock performance, availability of inertial sensors, and constellation coverage. Example: present-day GPS carry 10(exp -13) clocks and require several updates per day. With 10(exp -15) clocks, a constellation at Mars could operate autonomously with updates just once per month. Use of GPS tracking at the Moon should be evaluated in a technical study.

Lichten, Stephen M.

2004-01-01

107

RANGE - Robust autonomous navigation in GPS-denied environments  

E-print Network

This video highlights our system that enables a Micro Aerial Vehicle (MAV) to autonomously explore and map unstructured and unknown GPS-denied environments. While mapping and exploration solutions are now well-established ...

Bachrach, Abraham Galton

108

Redundant multi-mode filter for a navigation system  

Microsoft Academic Search

An approach is introduced to the design of a multi-mode navigation filter to combine a low-cost skewed redundant inertial measurement unit (SRTMU) with a multifunctional GPS (MF-GPS) receiver in order to implement a fault-tolerant aircraft navigation system, which can achieve the required navigation performance of conventional systems in terms of accuracy, integrity, continuity, and availability. The MF-GPS receiver provides raw

DAVID J. ALLERTON; Huamin Jia

2007-01-01

109

Global Navigation Satellite Systems (GNSSs) for Monitoring Long Suspension Bridges  

E-print Network

, Nanjing, China 1 A Brief Introduction to the Global Positioning System 1 2 GPS for Structural Health 16 1 A BRIEF INTRODUCTION TO THE GLOBAL POSITIONING SYSTEM 1.1 GPS constellation The full term of the well-known acronym GPS is NAVSTAR global positioning system, where NAVSTAR stands for NAVigation System

Santerre, Rock

110

SPACECRAFT NAVIGATION USING THE MODERNIZED GLOBAL POSITIONING SYSTEM SIGNAL  

E-print Network

SPACECRAFT NAVIGATION USING THE MODERNIZED GLOBAL POSITIONING SYSTEM SIGNAL E. G. Lightsey and R. B The utility of the Global Positioning System (GPS) for spacecraft navigation and timing has been widely

Lightsey, Glenn

111

Differential GPS/inertial navigation approach/landing flight test results  

NASA Technical Reports Server (NTRS)

In November of 1990 a joint Honeywell/NASA-Langley differential GPS/inertial flight test was conducted at Wallops Island, Virginia. The test objective was to acquire a system performance database and demonstrate automatic landing using an integrated differential GPS/INS (Global Positioning System/inertial navigation system) with barometric and radar altimeters. The flight test effort exceeded program objectives with over 120 landings, 36 of which were fully automatic differential GPS/inertial landings. Flight test results obtained from post-flight data analysis are discussed. These results include characteristics of differential GPS/inertial error, using the Wallops Island Laser Tracker as a reference. Data on the magnitude of the differential corrections and vertical channel performance with and without radar altimeter augmentation are provided.

Snyder, Scott; Schipper, Brian; Vallot, Larry; Parker, Nigel; Spitzer, Cary

1992-01-01

112

Networked differential GPS system  

NASA Technical Reports Server (NTRS)

An embodiment of the present invention relates to a worldwide network of differential GPS reference stations (NDGPS) that continually track the entire GPS satellite constellation and provide interpolations of reference station corrections tailored for particular user locations between the reference stations Each reference station takes real-time ionospheric measurements with codeless cross-correlating dual-frequency carrier GPS receivers and computes real-time orbit ephemerides independently. An absolute pseudorange correction (PRC) is defined for each satellite as a function of a particular user's location. A map of the function is constructed, with iso-PRC contours. The network measures the PRCs at a few points, so-called reference stations and constructs an iso-PRC map for each satellite. Corrections are interpolated for each user's site on a subscription basis. The data bandwidths are kept to a minimum by transmitting information that cannot be obtained directly by the user and by updating information by classes and according to how quickly each class of data goes stale given the realities of the GPS system. Sub-decimeter-level kinematic accuracy over a given area is accomplished by establishing a mini-fiducial network.

Mueller, K. Tysen (Inventor); Loomis, Peter V. W. (Inventor); Kalafus, Rudolph M. (Inventor); Sheynblat, Leonid (Inventor)

1994-01-01

113

Simultaneous visual target tracking and navigation in a GPS-denied environment  

Microsoft Academic Search

This paper proposes a visual navigation system for an unmanned aerial vehicle to track a moving ground object in a GPS-denied environment. Image processing combines a target tracker which provides pixel coordinates of a ground target, and the estimation of optical flow around the detected target position. An extended Kalman filter is applied to estimate position and velocity of the

Yoko Watanabe; Patrick Fabiani; Guy Le Besnerais

2009-01-01

114

A LEO Satellite Navigation Algorithm Based on GPS and Magnetometer Data  

NASA Technical Reports Server (NTRS)

The Global Position System (GPS) has become a standard method for low cost onboard satellite orbit determination. The use of GPS as an attitude and rate sensor has also been developed in the recent past. Additionally, focus has been given to attitude and orbit estimation using the magnetometer, a low cost, reliable sensor. Combining measurements from both GPS and a magnetometer can provide a robust navigation system which takes advantage of the estimation qualities of both measurements. Ultimately a low cost, accurate navigation system can result, potentially eliminating the need for more costly sensors, including gyroscopes. This work presents the development and preliminary testing of a unified navigation algorithm which produces estimates of attitude, angular rate, position, and velocity for a low earth orbit (LEO) spacecraft. The system relies on GPS phase, range, and range rate data as well as magnetometer data. The algorithm used is an extended Kalman filter (EKF) developed to provide LEO attitude, orbit, and rate estimates using magnetometer and sun sensor data. Incorporating sun sensor data into the EKF improved the attitude and rate estimates. For many LEO spacecraft the sun data is available during only a portion of the orbit. However, GPS data is available continuously throughout the orbit. GPS can produce accurate orbit estimates and combining GPS and magnetometer data improves the attitude and rate estimates. The magnetometer based EKF can converge from large initial errors in position, velocity, and 3 attitude . Combining the magnetometer and GPS data into a single EKF will provide a more robust and accurate system. The EKF is based on an existing EKF. The GPS measurement models for phase, range, and range rate are incorporated into the existing structure of the filter. The original EKF produced the orbit estimates in terms of Keplerian elements. Due to the nature of the GPS measurements and ease of computation, the orbit estimates are converted to the Cartesian position and velocity. The measurement model for the magnetometer is adjusted for this change in the state and the measurements. Preliminary test results based on simulated GPS and magnetometer data are included.

Deutschmann, Julie; Bar-Itzhack, Itzhack Y.; Harman, Rick

2000-01-01

115

Benefits of combined GPS/GLONASS with low-cost MEMS IMUs for vehicular urban navigation.  

PubMed

The integration of Global Navigation Satellite Systems (GNSS) with Inertial Navigation Systems (INS) has been very actively researched for many years due to the complementary nature of the two systems. In particular, during the last few years the integration with micro-electromechanical system (MEMS) inertial measurement units (IMUs) has been investigated. In fact, recent advances in MEMS technology have made possible the development of a new generation of low cost inertial sensors characterized by small size and light weight, which represents an attractive option for mass-market applications such as vehicular and pedestrian navigation. However, whereas there has been much interest in the integration of GPS with a MEMS-based INS, few research studies have been conducted on expanding this application to the revitalized GLONASS system. This paper looks at the benefits of adding GLONASS to existing GPS/INS(MEMS) systems using loose and tight integration strategies. The relative benefits of various constraints are also assessed. Results show that when satellite visibility is poor (approximately 50% solution availability) the benefits of GLONASS are only seen with tight integration algorithms. For more benign environments, a loosely coupled GPS/GLONASS/INS system offers performance comparable to that of a tightly coupled GPS/INS system, but with reduced complexity and development time. PMID:22666079

Angrisano, Antonio; Petovello, Mark; Pugliano, Giovanni

2012-01-01

116

Intelligent navigation of unmanned land vehicle by using GPS & one ABS sensor  

Microsoft Academic Search

Navigation for unmanned vehicles always required correct positions during the movement of vehicle. Normally GPS is considered a valuable tool for the purpose of navigation and surveillance. Any obstruction in the area of GPS antenna can cause very significant reduction in accuracy. Therefore, GPS-INS based solution is utilized to improve accuracy. In case of small vehicles (like TOY cars), hardware

Syed Riaz; Nabi Jafri; Syed Minhaj; Syed Zeeshan Shakeel

2009-01-01

117

Landsat/4/Global Positioning System navigation results  

NASA Technical Reports Server (NTRS)

An experimental GPSPAC flown on the Landsat-4 spacecraft was the first spaceborne navigation system to use the NAVSTAR Global Position System (GPS). In order to validate the accuracy and reliability of GPSPAC orbit solutions, definitive Landsat-4 ephemerides, derived from ground based tracking data, were generated and compared with GPSPAC estimates. In addition, Landsat-4 orbital solutions were reconstructed from raw GPS measurement data with a GPSPAC navigation simulator program using different Kalman filter constants. Ephemeris comparisons and simulator results are presented, as well as recommendations for the navigation filter.

Heuberger, H.; Church, L.

1984-01-01

118

A New Centimeter-Level Real-Time Global Navigation and Positioning Capability with GPS  

NASA Technical Reports Server (NTRS)

NASA/JPL has developed a new, precise, global, GPS-based capability for real-time terrestrial and space platform navigation. It has been demonstrated on Earth's surface and is 10 times more accurate than other real-time GPS-based systems. The new system poses certain advantages for Earth science remote sensing, including: the onboard generation of science data products in real-time, sensor control and reduction of data transmission bandwidth, improved environmental forecasting, autonomous and intelligent platform control, operations cost savings, and technology transfer and commercial partnership opportunities. The system's measurement capabilities and applications, demonstrated orbit accuracies, and precision LEO and spacecraft positioning and timing are highlighted.

Bar-Sever, Yoaz

2001-01-01

119

SIGNAL QUALITY MONITORING FOR GPS AUGMENTATION SYSTEMS  

E-print Network

was to provide accurate navigation, guidance, and time transfer to military users. The past decade has also seen: a significant signal anomaly on GPS satellite SV 19, initially observed in March 1993. At the time, a tenfold System is a network of satellites, deployed by the U.S. Depart- ment of Defense, whose original purpose

Stanford University

120

GPS(global positioning system) , , . D. Patterson GPS(Global Positioning  

E-print Network

. . . GPS(global positioning system) , , , , [1]. , . . . . D. Patterson GPS(Global Positioning System) GPS [2]. D. Ashbrook GPS k-means [3]. . . GPS . GPS 10m . SOM(self-organizing map) . SOM GPS . . 1 . , . RSOM(recurrent SOM) . SOM . RSOM SOM [4]. SOM . GPS . #12;GPS Sensor Train SOM Build Local

Cho, Sung-Bae

121

Embedded Low Cost Inertial Navigation System 1  

Microsoft Academic Search

This paper will discuss the design and implementation of an embedded low cost inertial navigation system (INS) using an inertial measurement unit (IMU), digital compass, GPS, and an embedded computer system. The INS is capable of providing continuous estimates of a vehicle's position and orientation. Typically IMU's are very expensive systems, however this INS will use \\

Kevin J. Walchko; Michael C. Nechyba; Eric Schwartz; Antonio Arroyo

122

Testing the Preliminary X-33 Navigation System  

NASA Technical Reports Server (NTRS)

The X-33 Reusable Launch Vehicle (RLV) must meet the demanding requirements of landing autonomously on a narrow landing strip following a flight that reaches an altitude of up to 200,000 feet and a speed in excess of Mach 9 with significant in-flight energy bleed-off maneuvers. To execute this flight regimen a highly reliable avionics system has been designed that includes three LN-100G Inertial Navigation System/Global Positioning System (INS/GPS) units as the primary navigation system for the X-33. NASA's Marshall Space Flight Center (MSFC) tested an INS/GPS system in real-time simulations to determine the ability of this navigation suite to meet the in flight and autonomous landing requirements of the X-33 RLV. A total of sixty-one open loop tests were performed to characterize the navigation accuracy of the LN-100G. Twenty-seven closed-loop tests were also performed to evaluate the performance of the X-33 Guidance, Navigation and Control (GN&C) algorithms with the real navigation hardware. These closed-loop tests were also designed to expose any integration or operational issues with the real-time X-33 vehicle simulation. Dynamic road tests of the INS/GPS were conducted by Litton to assess the performance of differential and nondifferential INS/GPS hybrid navigation solutions. The results of the simulations and road testing demonstrate that this novel solution is capable of meeting the demanding requirements of take-off, in-flight navigation, and autonomous landing of the X-33 RLV. This paper describes the test environment developed to stimulate the LN-100G and discusses the results of this test effort. This paper also presents recommendations for a navigation system suitable to an operational RLV system.

Lomas, James J.; Mitchell, Daniel W.; Freestone, Todd M.; Lee, Charles; Lessman, Craig; Foster, Lee D. (Technical Monitor)

2001-01-01

123

Matching Raw GPS Measurements on a Navigable Map Without Computing a Global Position  

E-print Network

1 Matching Raw GPS Measurements on a Navigable Map Without Computing a Global Position Clément with respect to a road network description stored in a digital map. This problem is usually addressed using GPS because of outages due to tall buildings. In this paper, map-matching is solved using raw GPS measurements

Paris-Sud XI, Université de

124

Application of aircraft navigation sensors to enhanced vision systems  

NASA Technical Reports Server (NTRS)

In this presentation, the applicability of various aircraft navigation sensors to enhanced vision system design is discussed. First, the accuracy requirements of the FAA for precision landing systems are presented, followed by the current navigation systems and their characteristics. These systems include Instrument Landing System (ILS), Microwave Landing System (MLS), Inertial Navigation, Altimetry, and Global Positioning System (GPS). Finally, the use of navigation system data to improve enhanced vision systems is discussed. These applications include radar image rectification, motion compensation, and image registration.

Sweet, Barbara T.

1993-01-01

125

An Inertial Navigation System for Small Autonomous Underwater Vehicles  

Microsoft Academic Search

A small AUV navigation system (SANS) has been developed at the Naval Postgraduate School. The SANS is an integrated GPS\\/INS navigation system composed of low-cost, small-size components. It is designed to demonstrate the feasibility of using a low-cost inertial measurement unit to navigate between intermittent GPS fixes. This paper reports recent improvements to the SANS hardware, latest testing results after

Xiaoping Yun; Eric R. Bachmann; Suat Arslan

2000-01-01

126

The Future of Global Navigation Satellite Systems  

Microsoft Academic Search

Global Navigation Satellite Systems (GNSSs) involve satellites, ground stations and user equipment, and are now used across many areas of society. The Global Positioning System (GPS) from the US is the best known, and only currently fully operational GNSS. Russia also operates its own (not fully deployed) GNSS called GLONASS. Fuelling growth in applications during the next decade will be

Chris RIZOS

127

An improved federated filtering method for integrated navigation system of Autonomous Underwater Vehicle  

Microsoft Academic Search

To improve the navigation accuracy of AUV (autonomous underwater vehicle), SINS (strapdown inertial navigation system), GPS (global positioning system), DVL (Doppler velocity log) and TAN (terrain aided navigation) are adopted in the AUV integrated navigation system. The mathematic model of the AUV integrated navigation system and the observation model of the chosen navigation sensors are built according to the system

Shimei Duan; Fengju Kang; Yanfang Fu; Yankai Wang

2008-01-01

128

Inertial navigation systems analysis.  

NASA Technical Reports Server (NTRS)

This volume offers the avionic systems engineer a fundamental exposition of the mechanization and error analysis of inertial navigation systems. While the material is applicable to spacecraft and undersea navigation, emphasis is placed upon terrestrial applications on or slightly above the earth's surface. As a result, practical considerations are geared toward those aircraft navigation systems of particular current interest. Extensive use is made of perturbation techniques to develop linearized system equations, whose solutions closely approximate those obtained by nonlinear differential equations. A unified error analysis technique is developed that is applicable to virtually all system configurations. The technique provides a greatly simplified method for comparing the performance of competing system configurations.

Britting, K. R.

1971-01-01

129

Introduction to Global Navigation Satellite System  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the fundamentals of satellite navigation, and specifically how GPS works. It presents an overview and status of Global Positioning System, for both the current GPS, and plans to modernize it in the future. There is also a overview and status of other Global Navigation Satellite System (GNSS), specifically GLONASS, Galileo, and QZSS. There is also a review of Satellite based time transfer techniques. The topic is of interest to the Time and Frequency Community, because the Global Positioning system has become the primary system for distributing Time and frequency globally, and because it allows users to synchronize clocks and calibrate and control oscillators in any location that has a GPS antenna.

Moreau, Michael

2005-01-01

130

Regional Navigation System Using Geosynchronous Satellites and Stratospheric Airships  

E-print Network

he or she is at. Now the Global Positioning System (GPS) provides the ultimate solution is possible. Because there already exists a fully functional global positioning system (i.e., GPS), we propose navigation using just this augmented system without the aid of the existing global positioning system

Won, Chang-Hee

131

Institute of Navigation National Technical Meeting/Anaheim, CA/January 26-28,2000 1 LOW COST INS/GPS INTEGRATION  

E-print Network

, and has worked extensively on the integration of GPS and inertial navigation systems for precise aircraft and Navigation Systems at Bauman Moscow State Technical University, and Adjunct Professor in the Department of inertial units is the main obstacle for their inclusion in precision navigation systems to support

Calgary, University of

132

Foot mounted inertial system for pedestrian navigation  

NASA Astrophysics Data System (ADS)

This paper discusses algorithmic concepts, design and testing of a system based on a low-cost MEMS-based inertial measurement unit (IMU) and high-sensitivity global positioning system (HSGPS) receivers for seamless personal navigation in a GPS signal degraded environment. The system developed here is mounted on a pedestrian shoe/foot and uses measurements based on the dynamics experienced by the inertial sensors on the user's foot. The IMU measurements are processed through a conventional inertial navigation system (INS) algorithm and are then integrated with HSGPS receiver measurements and dynamics derived constraint measurements using a tightly coupled integration strategy. The ability of INS to bridge the navigation solution is evaluated through field tests conducted indoors and in severely signal degraded forest environments. The specific focus is on evaluating system performance under challenging GPS conditions.

Godha, S.; Lachapelle, G.

2008-07-01

133

GPS inferred geocentric reference frame for satellite positioning and navigation  

NASA Technical Reports Server (NTRS)

Accurate geocentric three-dimensional positioning is of great importance for various geodetic and oceanographic applications. While relative positioning accuracy of a few centimeters has become a reality using Very Long Baseline Interferometry (VLBI), the uncertainty in the offset of the adopted coordinate system origin from the geocenter is still believed to be of the order of one meter. Satellite Laser Ranging (SLR) is capable of determining this offset to better than 10 cm, though, because of the limited number of satellites, this requires a long arc of data. The Global Positioning System (GPS) measurements provide a powerful alternative for an accurate determination of this origin offset in relatively short period of time. Two strategies are discussed, the first utilizes the precise relative positions predetermined by VLBI, whereas the second establishes a reference frame by holding only one of the tracking sites longitude fixed. Covariance analysis studies indicate that geocentric positioning to an accuracy of a few centimeters can be achieved with just one day of precise GPS pseudorange and carrier phase data.

Malla, Rajendra P.; Wu, Sien-Chong

1989-01-01

134

Robust guidance and navigation for airborne vehicles using GPS\\/terrain aiding  

Microsoft Academic Search

The emergence of new technologies for terrain elevation data collection allows the possibility of much improved terrain elevation model resolution and accuracy. This presents an opportunity for high accuracy navigation of airborne vehicles at modest cost and at the same time, less reliance on GPS navigation. In this paper, we present a concept for airborne en route and terminal navigation

John E. Pritchett; Alan J. Pue

2000-01-01

135

Tightly coupled low cost 3D RISS/GPS integration using a mixture particle filter for vehicular navigation.  

PubMed

Satellite navigation systems such as the global positioning system (GPS) are currently the most common technique used for land vehicle positioning. However, in GPS-denied environments, there is an interruption in the positioning information. Low-cost micro-electro mechanical system (MEMS)-based inertial sensors can be integrated with GPS and enhance the performance in denied GPS environments. The traditional technique for this integration problem is Kalman filtering (KF). Due to the inherent errors of low-cost MEMS inertial sensors and their large stochastic drifts, KF, with its linearized models, has limited capabilities in providing accurate positioning. Particle filtering (PF) was recently suggested as a nonlinear filtering technique to accommodate for arbitrary inertial sensor characteristics, motion dynamics and noise distributions. An enhanced version of PF called the Mixture PF is utilized in this study to perform tightly coupled integration of a three dimensional (3D) reduced inertial sensors system (RISS) with GPS. In this work, the RISS consists of one single-axis gyroscope and a two-axis accelerometer used together with the vehicle's odometer to obtain 3D navigation states. These sensors are then integrated with GPS in a tightly coupled scheme. In loosely-coupled integration, at least four satellites are needed to provide acceptable GPS position and velocity updates for the integration filter. The advantage of the tightly-coupled integration is that it can provide GPS measurement update(s) even when the number of visible satellites is three or lower, thereby improving the operation of the navigation system in environments with partial blockages by providing continuous aiding to the inertial sensors even during limited GPS satellite availability. To effectively exploit the capabilities of PF, advanced modeling for the stochastic drift of the vertically aligned gyroscope is used. In order to benefit from measurement updates for such drift, which are loosely-coupled updates, a hybrid loosely/tightly coupled solution is proposed. This solution is suitable for downtown environments because of the long natural outages or degradation of GPS. The performance of the proposed 3D Navigation solution using Mixture PF for 3D RISS/GPS integration is examined by road test trajectories in a land vehicle and compared to the KF counterpart. PMID:22163846

Georgy, Jacques; Noureldin, Aboelmagd

2011-01-01

136

Accuracy and performance of augmentations to global navigation systems outside their areas of coverage  

Microsoft Academic Search

Signals broadcasted by Global Positioning System are a good solution for aircraft navigation in remote areas where conventional ground?based navigation means do not exist. In the world of avionics, more and more navigation guidance systems based on GPS are being developed. Very high claims in terms of accuracy, reliability, and integrity are required for such systems. But GPS alone cannot

J. Stank?nas; A. Jaku?ionis; V. Petrusevi?ius

2005-01-01

137

An Effective Approach to Improving Low-Cost GPS Positioning Accuracy in Real-Time Navigation  

PubMed Central

Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previously estimated precious reference point, coordinate translation, and invalid data check also improve accuracy. In order to evaluate the performance of the proposed method, we conducted an experiment using a GARMIN GPS 19xHVS receiver attached to a car and used Google Maps to plot the processed data. The proposed method achieved improvement of 4–10 meters in several experiments. In addition, we compared the proposed approach with two other state-of-the-art methods: recursive averaging and ARMA interpolation. The experimental results show that the proposed approach outperforms other state-of-the-art methods in terms of positioning accuracy. PMID:25136679

Islam, Md. Rashedul; Kim, Jong-Myon

2014-01-01

138

gpsTunes controlling navigation via audio feedback Steven Strachan1  

E-print Network

Global Positioning System (GPS) with that of an MP3 player, implemented on a PocketPC, to produce example of a pocket-sized location aware system, based on GPS (Global Positioning System) signals, which

Murray-Smith, Roderick

139

Laser Inertial Navigation System  

NASA Technical Reports Server (NTRS)

Acceptable accuracy obtained with short alignment time. Report describes successful helicopter tests of laser inertial navigational equipment. Tests conducted over 3-year period, both in laboratory and flight. Inertial system used as position/velocity/attitude indicator and later also served as part of automatic flight-control system.

Hruby, R. J.; Xenakis, G.; Carestia, R. A.; Bjorkman, W. S.; Schmit, S. F.; Corliss, L. D.

1986-01-01

140

Real-Time Navigation Using the Global Positioning System Real-Time Navigation Using the Global Positioning System  

E-print Network

For more than a decade, TRW has been involved in aerospace applications of the Global Positioning System (GPS). TRW Ballistic Missiles Division first began working with GPS on a Minuteman missile test flight program in 1980. Since then, TRW has applied GPS to programs such as the Peacekeeper missile, the F-22 fighter aircraft, the Orbital Maneuvering Vehicle, Brilliant Pebbles, and classified satellites. This paper presents the results of an investigation of the application of GPS to real-time integrated missile navigation. We present quantifiable measures of navigation accuracy as a function of GPS receiver parameters. We also formulate some new phase-locked loop (PLL) filter designs, and demonstrate their superiority over more conventional filters. The National Aeronautical Association describes the Global Positioning System as “the most significant development for safe and efficient navigation

unknown authors

141

Navigation Overview Types of Navigation  

E-print Network

-reckoning ­ Landmarks/Beacons ­ Aircraft compass and Airspeed Indicator · Radio Navigation ­ Non-directional Radio Navigation ­ Inertial Navigation System (INS) · Satellite Navigation Systems ­ Global Positioning System (GPS to you" · At airports and on routes between airports ­ Inertial Navigation System (INS) · "This is your

142

Design and implementation of small navigation system on land vehicle  

NASA Astrophysics Data System (ADS)

This paper is focused on the problem of frame loss and truncation on multi-channel universal asynchronous receiver transmitter (UART) embedded in Integrated Navigation Systems, and it contains attitude heading reference system (AHRS) and global positioning system (GPS). An advanced design based on FPGA and ARM processor is discussed in this paper, in which FPGA would be used to coordinate with each logic modules, expand UART for GPS and AHRS, resolve navigation information, and save specify data to SD card, which can reduce the delay in data receiving and resolving, while ARM is applied in the area of parameters estimation and navigation algorithms. The experiment results show that this navigation system can use UART to receive, resolve data frames and save data while ARM execute parameter estimation and navigation algorithms in real time. This integrated navigation can effectively avoid the phenomenon of data frame loss or truncation in UART receiving, and can improve the navigation precision.

Ma, Shuaiqi

2013-03-01

143

Cloud Absorption Radiometer Autonomous Navigation System - CANS  

NASA Technical Reports Server (NTRS)

CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode, the software aligns the precision navigation sensors and initializes the communications interfaces with the sensor and the remote computing system. It also monitors the navigation data state for quality and ensures that the system maintains the required fidelity for attitude and positional information. In the operational mode, the software runs at 12.5 Hz and gathers the required navigation/attitude data, computes the required sensor correction values, and then commands the sensor to the required roll correction. In this manner, the sensor will stay very near to vertical at all times, greatly improving the resulting collected data and imagery. CANS greatly improves quality of resulting imagery and data collected. In addition, the software component of the system outputs a concisely formatted, high-speed data stream that can be used for further science data processing. This precision, time-stamped data also can benefit other instruments on the same aircraft platform by providing extra information from the mission flight.

Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

2013-01-01

144

An advanced system for performance evaluation of integrated navigation systems  

Microsoft Academic Search

• A test system designed for field performance evaluation of integrated aircraft navigation systems was described. It is based on off-line data processing and analysis of inertial sensors' measurements and carrier phase differential GPS data from multiple antennas • First experimental tests were carried out on ground using a partial version of the test setup. Results are promising: • Off

Giancarmine Fasano; Alfredo Renga; Domenico Accardo; Michele Grassi; Roberto Senatore

2011-01-01

145

Use of a Reduced IMU to Aid a GPS Receiver with Adaptive Tracking Loops for Land Vehicle Navigation  

E-print Network

/IMU integration; Reduced IMU; Inertial-aided GPS receiver; Adaptive loop filter; Land vehicle navigation Introduction In land vehicle navigation (LVN) applications, reduced inertial measurement units (IMU) canUse of a Reduced IMU to Aid a GPS Receiver with Adaptive Tracking Loops for Land Vehicle Navigation

Calgary, University of

146

High accuracy integrated global positioning system/inertial navigation system LDRD: Final report  

SciTech Connect

This report contains the results of a Sandia National Laboratories Directed Research and Development (LDRD) program to investigate the integration of Global Positioning System (GPS) and inertial navigation system (INS) technologies toward the goal of optimizing the navigational accuracy of the combined GPSANS system. The approach undertaken is to integrate the data from an INS, which has long term drifts, but excellent short term accuracy, with GPS carrier phase signal information, which is accurate to the sub-centimeter level, but requires continuous tracking of the GPS signals. The goal is to maintain a sub-meter accurate navigation solution while the vehicle is in motion by using the GPS measurements to estimate the INS navigation errors and then using the refined INS data to aid the GPS carrier phase cycle slip detection and correction and bridge dropouts in the GPS data. The work was expanded to look at GPS-based attitude determination, using multiple GPS receivers and antennas on a single platform, as a possible navigation aid. Efforts included not only the development of data processing algorithms and software, but also the collection and analysis of GPS and INS flight data aboard a Twin Otter aircraft. Finally, the application of improved navigation system accuracy to synthetic aperture radar (SAR) target location is examined.

Owen, T.E.; Meindl, M.A.; Fellerhoff, J.R.

1997-03-01

147

An embedded high sensitivity navigation receiver for GPS  

Microsoft Academic Search

A high sensitivity navigation receiver based on FPGA and DSP was presented in this paper, which performed to mitigate cross correlations between multiple satellite signals. The hardware was consisted of RF parts, FPGA and DSP. The core chips were SPARTAN3 and TMS320VC5402, which were adapted to process navigation data and calculate user position. The RF Front-End received the navigation signal

Yangchun Shi; Lingwen Zhang; YouBao Liu

2011-01-01

148

Precise Real-Time Low Earth Orbitor Navigation With GPS  

NASA Technical Reports Server (NTRS)

Technology is currently available to support real-time on-board knowledge of the position of a low earth orbitor at the 5-15 meter level using the civilian broadcast GPS signal with sophisticated models and filtering techniques onboard the spacecraft.

Bertiger, W.; Haines, B.; Kuang, D.; Lough, M.; Lichten, S.; Muellerschoen, R. J.; Vigue, Y.; Wu, S.

1998-01-01

149

A simple visual navigation system for an UAV  

Microsoft Academic Search

We present a simple and robust monocular camera-based navigation system for an autonomous quadcopter. The method does not require any additional infrastructure like radio beacons, artificial landmarks or GPS and can be easily combined with other navigation methods and algorithms. Its computational complexity is independent of the environment size and it works even when sensing only one landmark at a

Tomas Krajnik; Matias Nitsche; Sol Pedre; Libor Preucil; Marta E. Mejail

2012-01-01

150

Pulsar Navigation in the Solar System  

E-print Network

The X-ray Pulsar-based Autonomous Navigation(XNAV) were recently tested which use the Crab pulsar (PSR B0531+21) in the USA Experiment on flown by the Navy on the Air Force Advanced Research and Global Observation Satellite (ARGOS) under the Space Test Program. It provide the way that the spacecraft could autonomously determine its position with respect to an inertial origin. Now I analysis the sensitivity of the exist instrument and the signal process to use radio pulsar navigation and discuss the integrated navigation use pulsar,then give the different navigation mission analysis and design process basically which include the space, the airborne, the ship and the land of the planet or the lunar.So the pulsar navigation can give the continuous position in deep spaces, that means we can freedom fly successfully in the solar system use celestial navigation that include pulsar and traditional star sensor.It also can less or abolish the depend of Global Navigation Satellite System which include GPS, GRONSS, Gali...

Dong, Jiang

2008-01-01

151

Pulsar Navigation in the Solar System  

E-print Network

The X-ray Navigation and Autonomous position Verification (XNAV) is tested which use the Crab pulsar under the Space Test Program that use starlight refraction. It provide the way that the spacecraft could autonomously determine its position with respect to an inertial origin. Now we analysis the sensitivity of the exist instrument and the signal process that use radio pulsar navigation and discuss the integrated navigation which use radio pulsar, then give the different navigation mission analysis and design process basically which include the space, the airborne, the ship and the land of the planet or the lunar. Our analysis show that we will have the stability profile (signal-to-noise is 5) that use a 2 meters antenna observe some strong sources of radio pulsar in 36 minutes which based on the today's technology. So the pulsar navigation can give the continuous position in deep space, hat means we can freedom fly successfully in the solar system use celestial navigation that include pulsar and traditional star sensor. It also can less or abolish the dependence to Global Navigation Satellite System (GNSS) which include GPS, GRONSS, Galileo and BeiDou et al.

Jiang Dong

2008-12-14

152

Interoperability of satellite-based augmentation systems for aircraft navigation  

Microsoft Academic Search

The Federal Aviation Administration (FAA) is pioneering a transformation of the national airspace system from its present ground based navigation and landing systems to a satellite based system using the Global Positioning System (GPS). To meet the critical safety-of-life aviation positioning requirements, a Satellite-Based Augmentation System (SBAS), the Wide Area Augmentation System (WAAS), is being implemented to support navigation for

Donghai Dai

2001-01-01

153

IMU/GPS System Provides Position and Attitude Data  

NASA Technical Reports Server (NTRS)

A special navigation system is being developed to provide high-quality information on the position and attitude of a moving platform (an aircraft or spacecraft), for use in pointing and stabilization of a hyperspectral remote-sensing system carried aboard the platform. The system also serves to enable synchronization and interpretation of readouts of all onboard sensors. The heart of the system is a commercially available unit, small enough to be held in one hand, that contains an integral combination of an inertial measurement unit (IMU) of the microelectromechanical systems (MEMS) type, Global Positioning System (GPS) receivers, a differential GPS subsystem, and ancillary data-processing subsystems. The system utilizes GPS carrier-phase measurements to generate time data plus highly accurate and continuous data on the position, attitude, rotation, and acceleration of the platform. Relative to prior navigation systems based on IMU and GPS subsystems, this system is smaller, is less expensive, and performs better. Optionally, the system can easily be connected to a laptop computer for demonstration and evaluation. In addition to airborne and spaceborne remote-sensing applications, there are numerous potential terrestrial sensing, measurement, and navigation applications in diverse endeavors that include forestry, environmental monitoring, agriculture, mining, and robotics.

Lin, Ching Fang

2006-01-01

154

A new multi-position calibration method for MEMS inertial navigation systems  

Microsoft Academic Search

The Global Positioning System (GPS) is a worldwide navigation system that requires a clear line of sight to the orbiting satellites. For land vehicle navigation, a clear line of sight cannot be maintained all the time as the vehicle can travel through tunnels, under bridges, forest canopies or within urban canyons. In such situations, the augmentation of GPS with other

Z F Syed; P Aggarwal; C Goodall; X Niu; N El-Sheimy

2007-01-01

155

Analysis on the One-Way Communication Capability of GPS Satellites in Orbit Transmitting Non-navigational Information  

Microsoft Academic Search

The GPS system is capable of the one-way communication (OWC) transmitting non-navigational information if the reserved bits of L1C Nav message and the newly-added CNav message types for L2C signal are utilized. Excluding the potential communication protocol overheads, a single frequency with one satellite transmits data at 0.5B\\/s; with the dual frequency transmission by using L1C and L2C frequencies and

Cheng Xi-jun; Xu Jiang-ning; Cao Ke-jin; Zhu Ying-bin

2009-01-01

156

GPS/Magnetometer Based Satellite Navigation and Attitude Determination  

NASA Technical Reports Server (NTRS)

In recent years algorithms were developed for orbit, attitude and angular-rate determination of Low Earth Orbiting (LEO) satellites. Those algorithms rely on measurements of magnetometers, which are standard, relatively inexpensive, sensors that are normally installed on every LEO satellite. Although magnetometers alone are sufficient for obtaining the desired information, the convergence of the algorithms to the correct values of the satellite orbital parameters, position, attitude and angular velocity is very slow. The addition of sun sensors reduces the convergence time considerably. However, for many LEO satellites the sun data is not available during portions of the orbit when the spacecraft (SC) is in the earth shadow. It is here where the GPS space vehicles (SV) can provide valuable support. This is clearly demonstrated in the present paper. Although GPS measurements alone can be used to obtain SC position, velocity, attitude and angular-rate, the use of magnetometers improve the results due to the synergistic effect of sensor fusion. Moreover, it is possible to obtain these results with less than three SVs. In this paper we introduce an estimation algorithm, which is a combination of an Extended Kalman Filter (EKF) and a Pseudo Linear Kalman Filter (PSELIKA).

Deutschmann, Julie; Bar-Itzhack, Itzhack; Harman, Rick; Bauer, Frank H. (Technical Monitor)

2001-01-01

157

Extended Kalman filter synthesis for integrated global positioning\\/inertial navigation systems  

Microsoft Academic Search

The integrated global position system (GPS)\\/inertial navigation system (INS) is a cost-effective way of providing an accurate and reliable navigation system for civil and military aviation. These systems also provide low cost solutions to mid-course navigation and guidance of medium- and long-range weapon systems. In this paper, an error model developed earlier is used for GPS\\/INS filter mechanization (F.A. Faruqi,

Farhan A. Faruqi; Kenneth J. Turner

2000-01-01

158

Vibrotactile Feedback in Steering Wheel Reduces Navigation Errors during GPS-Guided Car Driving  

E-print Network

Vibrotactile Feedback in Steering Wheel Reduces Navigation Errors during GPS-Guided Car Driving vibration motors are mounted onto the steering wheel of a driving simulator and driving experiments are performed in virtual environments under two different sensory conditions (auditory alone and auditory

Basdogan, Cagatay

159

Vision enhanced navigation for unmanned systems  

NASA Astrophysics Data System (ADS)

A vision based simultaneous localization and mapping (SLAM) algorithm is evaluated for use on unmanned systems. SLAM is a technique used by a vehicle to build a map of an environment while concurrently keeping track of its location within the map, without a priori knowledge. The work in this thesis is focused on using SLAM as a navigation solution when global positioning system (GPS) service is degraded or temporarily unavailable. Previous work on unmanned systems that lead up to the determination that a better navigation solution than GPS alone is first presented. This previous work includes control of unmanned systems, simulation, and unmanned vehicle hardware testing. The proposed SLAM algorithm follows the work originally developed by Davidson et al. in which they dub their algorithm MonoSLAM [1--4]. A new approach using the Pyramidal Lucas-Kanade feature tracking algorithm from Intel's OpenCV (open computer vision) library is presented as a means of keeping correct landmark correspondences as the vehicle moves through the scene. Though this landmark tracking method is unusable for long term SLAM due to its inability to recognize revisited landmarks, as opposed to the Scale Invariant Feature Transform (SIFT) and Speeded Up Robust Features (SURF), its computational efficiency makes it a good candidate for short term navigation between GPS position updates. Additional sensor information is then considered by fusing INS and GPS information into the SLAM filter. The SLAM system, in its vision only and vision/IMU form, is tested on a table top, in an open room, and finally in an outdoor environment. For the outdoor environment, a form of the slam algorithm that fuses vision, IMU, and GPS information is tested. The proposed SLAM algorithm, and its several forms, are implemented in C++ using an Extended Kalman Filter (EKF). Experiments utilizing a live video feed from a webcam are performed. The different forms of the filter are compared and conclusions are made on the effectiveness of the SLAM algorithm for use on the current unmanned vehicles in Purdue's Hybrid Systems Lab. Recommendations for future improvements in applying computer vision to unmanned systems are also presented in the final chapter.

Wampler, Brandon Loy

160

Wellborne inertial navigation system  

SciTech Connect

A phototype wireline tool which includes a downhole inertial platform and a surface computer to spatially map a well is described. The hardware consists of a single-gimbaled inertial platform with accelerometers and gyros to obtain three-axis motion information. The gyroscope and accelerometer outputs are transmitted to a computer at the surface which calculates probe attitude relative to north, east, and vertical. Double integration of the accelerometer data provides the position information. A conventional 7-conductor wireline is used for the system data transmission. System accuracy is enhanced by advances made in the computer software which processes the data received from the tool. The software uses statistical sampling estimation to obtain optimal estimates of the system errors. Measurement errors are determined by periodically stopping the tool during the logging procedure and observing the indicated velocity measurements. This procedure, known as Kalman filtering, results in increased accuracy of the data. Present mapping systems have an X-Y-Z location accuracy of +- 100 to +- 200 feet for a typical well depth of 10,000 feet. Test results show that the new system is accurate to about +- 1 foot per 1000 feet of well depth. Unlike conventional systems, the inertial navigator does not require any sort of projection of the cable length (which may not be accurately known). Also this system provides continuous data throughout the wellbore and logging speeds on the order of 10 ft/sec appear possible. The hardware and software associated with this mapping system are described and the recent field test results are reported.

Kelsey, J.R.

1983-01-01

161

Inertie-GPS (Global Positioning System): Un Mariage de Raison - a l'Essai (Inertial-Gps: A Marriage of Reason, an Analysis).  

National Technical Information Service (NTIS)

The coupling of inertial navigation methods with the Global Positioning System (GPS) is examined. The characteristics of various types of inertial systems are reviewed and past attempts at inertial/radionavigation hybridizations including those with multi...

P. Lloret, B. Capit

1986-01-01

162

Integrated GPS-aided Inertial Lidar and Optical Imaging Systems for Aerial Mapping  

Microsoft Academic Search

High-resolution airborne Lidar and optical imaging systems with onboard data collection based on the Global Positioning System (GPS) and inertial navigation syste ms (INS) technology may offer the means to gather accurate topographic map information. As a follow-up to earlier investigations, in May 2005 an airborne integrated GPS -aided inertial Lidar and optical imaging system was used to collect data

R. D. Sanchez; J. Mullins

163

Doppler lidar sensor for precision navigation in GPS-deprived environment  

NASA Astrophysics Data System (ADS)

Landing mission concepts that are being developed for exploration of solar system bodies are increasingly ambitious in their implementations and objectives. Most of these missions require accurate position and velocity data during their descent phase in order to ensure safe, soft landing at the pre-designated sites. Data from the vehicle's Inertial Measurement Unit will not be sufficient due to significant drift error after extended travel time in space. Therefore, an onboard sensor is required to provide the necessary data for landing in the GPS-deprived environment of space. For this reason, NASA Langley Research Center has been developing an advanced Doppler lidar sensor capable of providing accurate and reliable data suitable for operation in the highly constrained environment of space. The Doppler lidar transmits three laser beams in different directions toward the ground. The signal from each beam provides the platform velocity and range to the ground along the laser line-of-sight (LOS). The six LOS measurements are then combined in order to determine the three components of the vehicle velocity vector, and to accurately measure altitude and attitude angles relative to the local ground. These measurements are used by an autonomous Guidance, Navigation, and Control system to accurately navigate the vehicle from a few kilometers above the ground to the designated location and to execute a gentle touchdown. A prototype version of our lidar sensor has been completed for a closed-loop demonstration onboard a rocket-powered terrestrial free-flyer vehicle.

Amzajerdian, F.; Pierrottet, D. F.; Hines, G. D.; Petway, L. B.; Barnes, B. W.

2013-05-01

164

Navigation systems requirements for airborne interferometric SAR platforms  

Microsoft Academic Search

It is well known that by means of airborne interferometric SAR systems it is possible to generate high precision digital elevation models (DEM), although these platforms are seriously affected by motion instabilities. These deviations are recorded by navigation systems, such as GPS receivers and inertial units. The precision of these systems, and the subsequent off-line processing, determines the level of

Marc BARA; J. Monne; A. Broquetas

1999-01-01

165

A Wi-Fi\\/GPS integrated system for urban vehicle positioning  

Microsoft Academic Search

Providing an anytime, ubiquitous and reliable vehicular positioning system plays a key role in increasing road safety and transportation efficiency. Although the Global Positioning System (GPS) has been widely used in vehicle navigation, urban vehicle positioning is still a challenge because of the unavailability of GPS in dense metropolitan areas. To solve this problem, an advanced integration of Wi-Fi and

Henghui Lu; Sheng Zhang; Yuhan Dong; Xiaokang Lin

2010-01-01

166

Submeter navigation grid system concept  

Microsoft Academic Search

This paper describes a concept for a system that provides the capability for accurate targeting and weapon delivery within a prescribed geographic context. This system, entitled submeter navigation grid, defines a geographic region that enables targeting platforms to perform relative navigation to the centimetre level. Ultimately, targeting information is delivered to an appropriate tactical platform, and the system enables precision

John Dowdle; Karl Flueckiger

2000-01-01

167

Miniature Space GPS Receiver by Means of Automobile-Navigation Technology  

NASA Astrophysics Data System (ADS)

Miniature space GPS receivers have been developed by means of automobile-navigation technology. We expanded the frequency sweep range in order to cover large Doppler shift on orbit. We tested the performance in low earth orbits by means of a GPS simulator. The range error caused by the receiver is measured to be 0.9m in RMS. The receiver is tolerant for 20krad radiation. Receiver was on-boarded on INDEX (“REIMEI”) satellite, which was launched in 2005. Cold start positioning is confirmed repeatedly to finish within 30min on orbit. The short term random error of GPS positioning is as large as 1.5m for PDDP = 2.7 on orbit. The range error due to the receiver is 0.5m RMS from the flight data. These results on orbit are consistent with the simulation results by means of a GPS simulator. This miniature space GPS receiver is promising as an inexpensive space GPS receiver in commercial market.

Saito, Hirobumi; Mizuno, Takahide; Kawahara, Kousuke; Saiki, Takanao; Tuda, Yuichi; Fukushima, Yousuke; Hamada, Yusuke; Sasaki, Hiroyuki; Katumoto, Sachiko; Kuroki, Seiji; Kajikawa, Yasuhiro

168

Performance of an AUV navigation system at Arctic latitudes  

Microsoft Academic Search

In October 2001, the Monterey Bay Aquarium Research Institute (MBARI) operated an autonomous underwater vehicle (AUV) in the Arctic at latitudes exceeding 80°. The navigation instruments consisted of a ring-laser gyro inertial navigation system (INS) coupled with a DVL and GPS, a separate fiber-optic-based gyro-compass, and a traditional flux-gate AHRS system. The instruments were tested on deck, in open water,

Rob McEwen; Hans Thomas; Don Weber; Frank Psota

2005-01-01

169

An Integrated UAV Navigation System Based on Aerial Image Matching  

Microsoft Academic Search

The aim of this paper is to explore the possibility of using geo-referenced satellite or aerial images to augment an Unmanned Aerial Vehicle (UAV) navigation system in case of GPS failure. A vision based navigation system which combines inertial sensors, visual odometer and registration of a UAV on-board video to a given geo-referenced aerial image has been developed and tested

Gianpaolo Conte; Patrick Doherty

2008-01-01

170

Mobile GPS tracking system using Holger Vmel  

E-print Network

be recorded from launch site (or DSRC!) to avoid drop outs. · Need cell phone communication #12;Mobile GPS tracking system using STRATO Holger Vömel University of Colorado, CIRES and NOAA/CMDL #12;Mobile GPS tracking system using STRATO Huntsville soundings : November 1, 2002 November 2, 2002

Vömel, Holger

171

Department of Geomatics Engineering GPS Integrated Systems  

E-print Network

Department of Geomatics Engineering GPS Integrated Systems For Precision Farming By Hazen L. Gehue 20072 #12;THE UNIVERSITY OF CALGARY GPS Integrated Systems for Precision Farming by Hazen L. Gehue #12;iii ABSTRACT The consequences of homogeneous treatments of agricultural fields is investigated

Calgary, University of

172

NORAD TLE Type Orbit Determination of LEO Satellites Using GPS Navigation Solutions  

NASA Astrophysics Data System (ADS)

NORAD Two Line Elements (TLE) are widely used for the increasing number of small satellite mission operations and analysis. However, due to the irregular periodicity of generation of the NORAD TLE, a new TLE that is independent of NORAD is required. A TLE type Orbit Determination (TLEOD) has been developed for the generation of a new TLE. Thus, the TLEOD system can provide an Antenna Control Unit (ACU) with the orbit determination result in the type of a TLE, which provides a simple interface for the commercialized ACU system. For the TLEOD system, NORAD SGP4 was used to make a new orbit determination system. In addition, a least squares method was implemented for the TLEOD system with the GPS navigation solutions of the KOMPSAT-1. Considering both the Orbit Propagation (OP) difference and the tendency of B* value, the preferable span of the day in the observation data was selected to be 3 days. Through the OD with 3 days observation data, the OP difference was derived and compared with that of Mission Analysis and Planning (MAPS) for the KOMPSAT-1. It has the extent from 2 km after six days to 4 km after seven days. This is qualified enough for the efficiency of an ACU in image reception and processing center of the KOMPSAT-2.

Cho, Chang-Hwa; Lee, Byoung-Sun; Lee, Jeong-Sook; Kim, Jae-Hoon; Choi, Kyu-Hong

2002-09-01

173

Integrated Navigation System for the Second Generation Reusable Launch Vehicle  

NASA Technical Reports Server (NTRS)

An array of components in a laboratory at NASA's Marshall Space Flight Center (MSFC) is being tested by the Flight Mechanics Office to develop an integrated navigation system for the second generation reusable launch vehicle. The laboratory is testing Global Positioning System (GPS) components, a satellite-based location and navigation system, and Inertial Navigation System (INS) components, sensors on a vehicle that determine angular velocity and linear acceleration at various points. The GPS and INS components work together to provide a space vehicle with guidance and navigation, like the push of the OnStar button in your car assists you with directions to a specific address. The integration will enable the vehicle operating system to track where the vehicle is in space and define its trajectory. The use of INS components for navigation is not new to space technology. The Space Shuttle currently uses them. However, the Space Launch Initiative is expanding the technology to integrate GPS and INS components to allow the vehicle to better define its position and more accurately determine vehicle acceleration and velocity. This advanced technology will lower operational costs and enhance the safety of reusable launch vehicles by providing a more comprehensive navigation system with greater capabilities. In this photograph, Dr. Jason Chuang of MSFC inspects an INS component in the laboratory.

2002-01-01

174

High accuracy integrated global positioning system\\/inertial navigation system LDRD: Final report  

Microsoft Academic Search

This report contains the results of a Sandia National Laboratories Directed Research and Development (LDRD) program to investigate the integration of Global Positioning System (GPS) and inertial navigation system (INS) technologies toward the goal of optimizing the navigational accuracy of the combined GPSANS system. The approach undertaken is to integrate the data from an INS, which has long term drifts,

T. E. Owen; M. A. Meindl; J. R. Fellerhoff

1997-01-01

175

Shuttle Global Positioning System (GPS) system design study  

NASA Technical Reports Server (NTRS)

The various integration problems in the Shuttle GPS system were investigated. The analysis of the Shuttle GPS link was studied. A preamplifier was designed since the Shuttle GPS antennas must be located remotely from the receiver. Several GPS receiver architecture trade-offs were discussed. The Shuttle RF harmonics and intermode that fall within the GPS receiver bandwidth were analyzed. The GPS PN code acquisition was examined. Since the receiver clock strongly affects both GPS carrier and code acquisition performance, a clock model was developed.

Nilsen, P. W.

1979-01-01

176

Space shuttle navigation analysis. Volume 2: Baseline system navigation  

NASA Technical Reports Server (NTRS)

Studies related to the baseline navigation system for the orbiter are presented. The baseline navigation system studies include a covariance analysis of the Inertial Measurement Unit calibration and alignment procedures, postflight IMU error recovery for the approach and landing phases, on-orbit calibration of IMU instrument biases, and a covariance analysis of entry and prelaunch navigation system performance.

Jones, H. L.; Luders, G.; Matchett, G. A.; Rains, R. G.

1980-01-01

177

INS/GPS Technology Trends.  

National Technical Information Service (NTIS)

This paper focuses on accuracy and other technology trends for inertial sensors, Global Positioning Systems (GPS), and integrated Inertial Navigation System (INS)/GPS systems, including considerations of interference, that will lead to better than 1 meter...

G. T. Schmidt

2010-01-01

178

ASRS Database Report Set Global Positioning System (GPS) Reports  

E-print Network

ASRS Database Report Set Global Positioning System (GPS) Reports Report Set Description.........................................A variety of reports referencing use of Global Positioning System (GPS) devices. Update Number

179

Applicable Tracking Data Arcs for NORAD TLE Orbit Determination of the KOMPSAT-1 Satellite Using GPS Navigation Solutions  

NASA Astrophysics Data System (ADS)

NORAD Two Line Element (TLE) is very useful to simplify the ground station antenna pointing and mission operations. When a satellite operations facility has the capability to determine NORAD type TLE which is independent of NORAD, it is important to analyze the applicable tracking data arcs for obtaining the best possible orbit. The applicable tracking data arcs for NORAD independent TLE orbit determination of the KOMPSAT-1 using GPS navigation solutions was analyzed for the best possible orbit determination and propagation results. Data spans of the GPS navi gation solutions from 1 day to 5 days were used for TLE orbit determination and the results were used as initial orbit for SGP4 orbit propagation. The operational orbit determination results using KOMPSAT-1 Mission Analysis and Planning System (MAPS) were used as references for the comparisons. The best-matched orbit determination was obtained when 3 days of GPS navigation solutions were used. The resulting 4 days of orbit propagation results were within 2 km of the KOMPSAT-1 MAPS results.

Lee, Byoung-Sun

2005-09-01

180

Delay/Doppler-Mapping GPS-Reflection Remote-Sensing System  

NASA Technical Reports Server (NTRS)

A radio receiver system that features enhanced capabilities for remote sensing by use of reflected Global Positioning System (GPS) signals has been developed. This system was designed primarily for ocean altimetry, but can also be used for scatterometry and bistatic synthetic-aperture radar imaging. Moreover, it could readily be adapted to utilize navigation-satellite systems other than the GPS, including the Russian Global Navigation Satellite System GLONASS) and the proposed European Galileo system. This remote-sensing system offers both advantages and disadvantages over traditional radar altimeters: One advantage of GPS-reflection systems is that they cost less because there is no need to transmit signals. Another advantage is that there are more simultaneous measurement opportunities - one for each GPS satellite in view. The primary disadvantage is that in comparison with radar signals, GPS signals are weaker, necessitating larger antennas and/or longer observations. This GPS-reflection remote-sensing system was tested in aircraft and made to record and process both (1) signals coming directly from GPS satellites by means of an upward-looking antenna and (2) GPS signals reflected from the ground by means of a downward-looking antenna. In addition to performing conventional GPS processing, the system records raw signals for postprocessing as required.

Lowe, Stephen; Kroger, Peter; Franklin, Garth; LeBrecque, John; Lerma, Jesse; Lough, Michael; Marcin, Martin; Muellerschoen, Ronald; Spitzmesser, Donovan; Young, Lawrence

2003-01-01

181

A Regional Tropospheric Delay Model for the Indian Subcontinent with Application to GPS Based Aircraft Navigation  

NASA Astrophysics Data System (ADS)

Application of Global Positioning System (GPS) in satellite-based navigation essentially requires a priori knowledge of the tropospheric refraction effect of GPS signal. The tropospheric delay estimated by ray tracing through the earth's atmosphere employing appropriate altitude profile of refractivity, is modeled in terms of measurable surface atmospheric parameters such as pressure, temperature, humidity as well as columnar water vapor for different locations over the Indian subcontinent using the upper air data (Radiosonde measurements). Different analytical forms are examined for this purpose. These site-specific surface models for zenith hydrostatic delay (ZHD) and wet (non-hydrostatic) delay are first generated for eighteen different selected locations over the continent covering different climatic region, over a geographical extend 8oN-33oN and 60oE-90oE. Taking all these models into account a Unified surface model that in principle is applicable for the entire subcontinent is derived. In a limiting case when the surface measurements are not available they are to be modeled based on the geographical coordinate and time (day of the year). For this the UNB model employed in WAAS (US), developed based on U.S standard supplements, and is examined over the Indian tropical region. This study extended further by developing a Region-specific model using five years daily atmospheric data over the Indian subcontinent which coupled to the Unified surface model provides a Regional Tropospheric Delay (RTD) model. This model is more accurate over Indian region. Since RTD does not involve any real time measured atmospheric parameters and relies only on mean model values, the prediction using this model is inferior to that estimated based on surface measurements. The maximum uncertainty of RTD model is 8.2cm and the minimum uncertainty is 0.86cm (at one sigma level) depending on the location, while the unified model with real-time measured inputs provides the same with an uncertainty between 5.2cm (maximum) and 0.65cm (minimum). A further validation by comparing with GPS measurements from two IGS stations at Bangalore and Hyderabad showed that predictions made using the RTD model are within an rms deviation of +5.0 cm while those using UNB model is +7.0 cm. Under extreme weather conditions these periodic (RTD, UNB) models have limitations which can be reduced by using the NCEP/NCAR reanalysis data.

Saha, Korak; Saha, Korak; Raju C, Suresh; Parameswaran, Krishnaswamy

182

SIG Technology Review Summer 1994 57 Real-Time Navigation Using the Global Positioning System  

E-print Network

SIG Technology Review · Summer 1994 57 Real-Time Navigation Using the Global Positioning System Real-Time Navigation Using the Global Positioning System Dan Simon and Hossny El-Sherief, TRW Ballistic for this satellite-based navigation tool. Civilian applications of GPS are found in such areas as ship and aircraft

Simon, Dan

183

DESIGN AND PERFORMANCE ANALYSIS OF A LOW-COST AIDED DEAD RECKONING NAVIGATION SYSTEM  

Microsoft Academic Search

This paper presents an aided dead reckoning navigation system based on the fusion of inexpensive inertial, air data and magnetic sensors aided by a skeletal network of radio-navigation aids. In the future National Airspace System of the United States-in which GPS is slated to be the primary means of navigation alongside a very small skeletal network of existing ground based

D. Gebre-Egziabher; J. D. Powell; P. K. Enge

184

Mobile robot autonomous navigation using MEMS gyro north finding method in Global Urban System  

Microsoft Academic Search

This paper addresses the issue of autonomous navigation method based on MEMS sensor optimization for mobile robot in Global Urban System (GUS). A new GPS\\/INS (Inertial Navigation System) navigation scheme is proposed, based on MEMS gyro north-finding approach. Existing research in the area of GUS focuses on the issues related to SLAM (Simultaneous Localization and Mapping) and planned trajectory tracking,

Yuan Long Wei; Min Cheol Lee

2011-01-01

185

Joint positioning and navigation aiding system for underwater robots  

Microsoft Academic Search

This paper proposes a new joint positioning and navigation aiding system for underwater robots. In the scenario adopted, a submersed target carries a pinger that emits acoustic signals periodically, as determined by a low precision clock. The target is tracked from the surface by a set of buoys equipped with acoustic hydrophones\\/projectors, GPS receivers, and electronic circuitry that measures the

R. Sousa; A. Alcocer; P. Oliveira; R. Ghabcheloo; A. Pascoal

2008-01-01

186

Joint Positioning and Navigation Aiding Systems for Multiple Underwater Robots  

Microsoft Academic Search

This paper proposes a new joint positioning and navigation aiding system for multiple underwater robots. In the scenario adopted, each submersed target carries a pinger that emits acoustic signals periodically, as determined by a low precision clock. The targets are tracked from the surface by a set of buoys equipped with acoustic hydrophones\\/projectors, GPS receivers, and electronic circuitry that measures

R. Sous; P. Oliveira; T. Gaspar

187

International Global Navigation Satellite Systems Society IGNSS Symposium 2011  

E-print Network

in frequency of the GPS signal because of the relative movement of satellite and receiver) and 3) the alignment. The Doppler shift depends on the relative movement of the satellite and the receiver. If this is not knownInternational Global Navigation Satellite Systems Society IGNSS Symposium 2011 University of New

Sekercioglu, Y. Ahmet

188

Analysis of Spaceborne GPS Systems  

NASA Technical Reports Server (NTRS)

A reasonable amount of literature can be found on the general topic of GPS receiving antennas, but very little has been published on spaceborne GPS receiving antennas. This very new topic seems to be so far more of interest for the industrial world than for the academic community. For satellite applications, microstrip antennas are usually preferred over other types of antennas mainly because of their non-electrical characteristics, such as small size, relatively lightweight, shape, possibility of integration with microwave integrated circuits, and relatively low costs. Careful design of patch antennas could meet all the requirements (electrical and non-electrical) of GPS receiving antenna to be mounted on a tethered satellite.

Cosmo, Mario L.; Davis, James L.; Elosegui, Pedro; Hill, Michael; ScireScapuzzo, Francesca

1998-01-01

189

Low-cost inertial/GPS for ballistic missiles with application to unmanned systems  

NASA Astrophysics Data System (ADS)

Many advances in inertial navigation have been made over the last decade. Small, lightweight inertial measurement units (IMU) have been developed which provide suitable accuracy at a reasonable cost for many unmanned systems. Price has also dropped to previously unheard of levels (under 10,000 dollars for large buys). IMUs can be augmented with global positioning system (GPS) receivers to provide highly accurate and robust navigation capability. GPS receivers have also dropped in size and cost and are becoming an attractive option for coupling with an inertial system. GPS systems alone are vulnerable to jamming and are not a good choice for military applications where jamming is a consideration. Current Army policy is not to use GPS as a mission essential element. The focus of this paper will be on low cost IMUs with GPS and their application to unmanned vehicles. In particular, the program to add guidance to the multiple launch rocket system extended range rocket will be discussed.

Roberts, Chris E.; Jenkins, Philip N.; Osborn, Charles T.

1996-05-01

190

Using APEX to Model Anticipated Human Error: Analysis of a GPS Navigational Aid  

NASA Technical Reports Server (NTRS)

The interface development process can be dramatically improved by predicting design facilitated human error at an early stage in the design process. The approach we advocate is to SIMULATE the behavior of a human agent carrying out tasks with a well-specified user interface, ANALYZE the simulation for instances of human error, and then REFINE the interface or protocol to minimize predicted error. This approach, incorporated into the APEX modeling architecture, differs from past approaches to human simulation in Its emphasis on error rather than e.g. learning rate or speed of response. The APEX model consists of two major components: (1) a powerful action selection component capable of simulating behavior in complex, multiple-task environments; and (2) a resource architecture which constrains cognitive, perceptual, and motor capabilities to within empirically demonstrated limits. The model mimics human errors arising from interactions between limited human resources and elements of the computer interface whose design falls to anticipate those limits. We analyze the design of a hand-held Global Positioning System (GPS) device used for radical and navigational decisions in small yacht recalls. The analysis demonstrates how human system modeling can be an effective design aid, helping to accelerate the process of refining a product (or procedure).

VanSelst, Mark; Freed, Michael; Shefto, Michael (Technical Monitor)

1997-01-01

191

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR OPERATION AND INITIALIZATION OF THE MAGELLAN GPS SATELLITE NAVIGATOR (UA-F-22.1)  

EPA Science Inventory

The purpose of this SOP is to describe the general procedures for the operation and initialization of the Magellan Global Positioning System (GPS) Satellite Navigator. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the "Bord...

192

Differential GPS\\/inertial navigation approach\\/landing flight test results  

Microsoft Academic Search

In November 1990, a differential GPS\\/inertial flight test was conducted to acquire a system performance database and demonstrate automatic landing using an integrated differential GPS\\/INS with barometric and radar altimeters. Flight test results obtained from postflight data analysis are presented. These results include characteristics of DGPS\\/inertial error, using a laser tracker as a reference. In addition, data are provided on

S. Snyder; B. Schipper; L. Vallot; N. Parker; C. Spitzer

1992-01-01

193

Integrated communications and optical navigation system  

NASA Astrophysics Data System (ADS)

The Integrated Communications and Optical Navigation System (ICONS) is a flexible navigation system for spacecraft that does not require global positioning system (GPS) measurements. The navigation solution is computed using an Unscented Kalman Filter (UKF) that can accept any combination of range, range-rate, planet chord width, landmark, and angle measurements using any celestial object. Both absolute and relative orbit determination is supported. The UKF employs a full nonlinear dynamical model of the orbit including gravity models and disturbance models. The ICONS package also includes attitude determination algorithms using the UKF algorithm with the Inertial Measurement Unit (IMU). The IMU is used as the dynamical base for the attitude determination algorithms. This makes the sensor a more capable plug-in replacement for a star tracker, thus reducing the integration and test cost of adding this sensor to a spacecraft. Recent additions include an integrated optical communications system which adds communications, and integrated range and range rate measurement and timing. The paper includes test results from trajectories based on the NASA New Horizons spacecraft.

Mueller, J.; Pajer, G.; Paluszek, M.

2013-12-01

194

GPS Basics  

NSDL National Science Digital Library

The Federal Aviation Administration maintains the graphically impressive Global Positioning System (GPS) Basics Web site. From the history of the global positioning system and how it works to governmental policy that controls its use, this site does a good job of explaining all facets of what GPS is about without being overly technical. Interested visitors can explore some of the other links that cover satellite navigation topics as well, such as GPS programs; a library of documents, fact sheets, press releases, and news; frequently asked questions; links; and more. Anyone interested in mapping, navigation, or similar subjects will enjoy exploring the interesting information provided on this well designed site.

195

An integrated GPS attitude determination system for small satellites  

NASA Astrophysics Data System (ADS)

This dissertation develops attitude determination methods based on the Global Positioning System (GPS) for small satellites. A GPS attitude receiver is used in combination with other sensors planned for a small, three-axis stabilized satellite called JAWS AT. The other attitude sensors include fiber optic gyros and digital sun sensors. The development of integrated attitude determination systems contributes to critical national technological objectives identified for small spacecraft. A recent study by the National Research Council addresses key technologies for small satellite programs. One of their principal recommendations was that, 'GPS in various combinations with other guidance components can determine position and attitude very accurately, probably at significantly reduced weight and cost.' The report also identifies specific potential benefits of integrating OPS with other sensors on small spacecraft. 'Combining GPS and an inertial measurement unit (with gyroscopes, accelerometers, or trackers) offers major advantages by bounding errors of the inertial set, providing exceptionally good long-term references and thereby ensuring precise, on-board navigation and, with appropriate complimentary techniques, providing a higher level of redundancy and/or accuracy for position, velocity, and attitude.' This dissertation develops algorithms that result in improved accuracy and redundancy through the development of complimentary techniques for combining GPS measurements with gyroscopes and sun sensors.

Chesley, Bruce Carl

1995-07-01

196

Positioning for Range-Based Land Navigation Systems Using Surface Topography  

Microsoft Academic Search

There are many situations in which GPS is either unable to provide the desired level of accuracy or is unavailable. Use of a pseudolite-based system (possibly at non-GPS frequencies) for navigation can be a means for positioning during these times. In many cases a pseudolite system with ground based transmitters has difficulty in determining the height of the receiver accurately,

John H. R. Amt; John F. Raquet

197

Trends in inertial systems technology for high accuracy AUV navigation  

Microsoft Academic Search

Medium accuracy inertial systems of the 1 nautical mile per hour class, enjoyed significant acceptance in the market for land survey systems in the early 1970's-prior to the introduction of GPS. This occurred because such systems could be implemented with software that capitalized on “zero velocity updates” (ZUPTS) which enabled the resultant system to achieve real-time navigation accuracies of a

J. R. Huddle

1998-01-01

198

Handheld GPS and Mobile Mapping  

Microsoft Academic Search

Significant developments in the hardware and software of the Global Positioning System (GPS) in recent years have resulted in the extensive use of less expensive, integrated, extremely small GPS units\\/chips for positioning, navigation and location management. The latest progress and development of handheld GPS technology have opened new application avenues from positioning and navigation into other application domains. Through their

B. Xiao; K. Zhang

2002-01-01

199

Real-time Navigation, Guidance, and Control of a UAV using Low-cost Sensors  

E-print Network

) and Global Positioning System (GPS) receiver for the GNC. The INS/GPS navigation loop provides continuous structure of navigation, guidance and control loop in UAV. The Global Positioning System (GPS) can provide

Kim, Jonghyuk "Jon"

200

Navigating the System  

MedlinePLUS

... Video Games Video Sharing Sites Webcasts/ Webinars Widgets Wikis Follow Us on New Media News & Events Awareness ... in mind when you are moving through the medical and service system. IT IS IMPORTANT TO REMEMBER: ...

201

Navigation systems. [for interplanetary flight  

NASA Technical Reports Server (NTRS)

The elements of the measurement and communications network comprising the global deep space navigation system (DSN) for NASA missions are described. Among the measurement systems discussed are: VLBI, two-way Doppler and range measurements, and optical measurements carried out on board the spacecraft. Processing of navigation measurement is carried out using two modules: an N-body numerical integration of the trajectory (and state transition partial derivatives) based on pre-guessed initial conditions; and partial derivatives of simulated observables corresponding to each actual observation. Calculations of velocity correction parameters is performed by precise modelling of all physical phenomena influencing the observational measurements, including: planetary motions; tracking station locations, gravity field structure, and transmission media effects. Some of the contributions to earth-relative orbit estimate errors for the Doppler/range system on board Voyager are discussed in detail. A line drawing of the DSN navigation system is provided.

Jordan, J. F.

1985-01-01

202

Adaptive tuning of a Kalman filter using the fuzzy integral for an intelligent navigation system  

Microsoft Academic Search

This paper describes the development of an intelligent, adaptive tuning system for a Kalman filter to optimally integrate data from an inertial navigation system (INS) and the Global Positioning System (GPS). This system is particularly useful for accurate navigation of an aircraft during maneuvering periods. The tuning algorithm is based on fuzzy logic. Specifically, the inference method in the fuzzy

Roya Rahbari; Barrie W. Leach; Jeremy Dillon; C. W. de Silva

2002-01-01

203

Non-linear mathematical model for integrated global positioning\\/inertial navigation systems  

Microsoft Academic Search

In recent years there has been a major upsurge of interest in the integrated global positioning system (GPS)\\/inertial navigation system (INS) as a cost-effective way of providing accurate and reliable navigation aid for civil and military vehicles (ships, aircrafts, land vehicles). In this paper an error model is developed which can be used for GPS\\/INS filter mechanization. It is shown

Farhan A. Faruqi

2000-01-01

204

Road to Seamless Positioning: Hybrid Positioning System Combining GPS  

E-print Network

Road to Seamless Positioning: Hybrid Positioning System Combining GPS and Television Signals Ju-Yong Do jdo@stanford.edu GPS Lab Stanford University April 18, 2007 #12;Ju-Yong Do 2007/4/18 GPS: Time and Position Reference Time & Position (4D) Time (1D) Position (3D) + = (GPS: Global Positioning System) Hybrid

Stanford University

205

Data Stream Synchronization of Distributed Measurements Systems Using GPS Technology  

Microsoft Academic Search

Global Positioning System (GPS) satellite signals are used in time and frequency metrology in general and a GPS receiver can provide a reference signal for frequency and time synchronization in particular. GPS, well known as a versatile, global tool for positioning, has also become the primary system for distributing time and frequency. GPS delivers very precise time as a by-product

Detlef Helling; M. Hense; H. van der Auweraer; J. Leuridan

2005-01-01

206

Onboard navigation rendezvous expert system  

NASA Technical Reports Server (NTRS)

The Onboard Navigation rendezvous expert system is designed to aid the ground flight controller in monitoring the shuttle onboard navigation system. The system is designed to keep track of the navigation sensors and relative state vectors. In addition, the system also keeps an event log and fills out forms usually handled by the flight controller. This expert system is one of the few rendezvous specific systems being developed for the Mission Control Center. The expert system has been in development for six years. Through these years the system has seen hardware, software, and personnel changes. Initial development was done by the Information Systems Directorate (ISD) and Mission Operations Directorate (MOD) at Johnson Space Center. As of October 1, 1991 the system has been turned over to MOD. The system is completely developed except for some minor adjustments to the user interface. The rule base is in the verification stage with total certification of the system due to be completed by May 1992. Test cases for verification are obtained by saving data used for flight controller integrated simulations. The actual data comes from both the shuttle mission simulator and the Mission Control Center Computer. So far no actual flight data has been available. This paper covers all aspects of the system from the development history to the current hardware, software, and use of the system.

Kocen, Michelle

1991-01-01

207

Impact of Integrated GPS and the Quasi-Zenith Satellite System in the East Asian Region  

Microsoft Academic Search

The Quasi-zenith Satellite System is a satellite navigation system in Japan which is designed to complement and augment global-positioning satellites (GPS). This paper investigated the impact of the integration of GPS and development of the QZSS system in the East Asian Region. QZSS satellite constellation and signal structure are briefly introduced, four QZSS satellite orbit options (8-shaped, Egg-shaped 1, Asymmetric

Yun Zhang; Falin Wu; Akio Yasuda

2007-01-01

208

Adaptive tuning of a Kalman filter via fuzzy logic for an intelligent AUV navigation system  

Microsoft Academic Search

This paper describes the implementation of an intelligent navigation system, based on the integrated use of the global positioning system (GPS) and several inertial navigation system (INS) sensors, for autonomous underwater vehicle (AUV) applications. A simple Kalman filter (SKF) and an extended Kalman filter (EKF) are proposed to be used subsequently to fuse the data from the INS sensors and

D Loebis; R Sutton; J Chudley; W Naeem

2004-01-01

209

Differential GPS/inertial navigation approach/landing flight test results  

NASA Technical Reports Server (NTRS)

Results of a joint Honeywell/NASA-Langley differential GPS/inertial flight test conducted in November 1990 are discussed focusing on postflight data analysis. The test was aimed at acquiring a system performance database and demonstrating automatic landing based on an integrated differential GPS/INS with barometric and radar altimeters. Particular attention is given to characteristics of DGPS/inertial error and the magnitude of the differential corrections and vertical channel performance with and without altimeter augmentation. It is shown that DGPS/inertial integrated with a radar altimeter is capable of providing a precision approach and autoland guidance of manned return space vehicles within the Space Shuttle accuracy requirements.

Snyder, Scott; Schipper, Brian; Vallot, Larry; Parker, Nigel; Spitzer, Cary

1992-01-01

210

New Radar and Navigation Systems  

Microsoft Academic Search

It is not the intention of this paper to give a complete coverage of all new radar and navigation systems, but to concentrate rather more on specific areas and examples where microwaves are used. Also, general coverage of the radar area is felt to be unnecessary following the invited paper given by R. Voles at Microwave 74, however recent advances

K L Fuller

1975-01-01

211

The signal design of present satellite navigation system and its inspiration  

NASA Astrophysics Data System (ADS)

Navigation signals are the basis of satellite navigation systems, which determine the navigation systems' performance (such as tracking accuracy, anti-interference capability etc.), and are determined by some constraints (such as radio frequency resources, construction cost, technology level etc.). The aim of signal design is to select "proper" signals considering these above factors and make tradeoffs between performance and constraints. This paper will summarize the signal structure evolution of present satellite navigation and conclude some principles and issues which will be greatly valuable to our 2nd satellite navigation system. There's four main satellite positioning systems presently, the U.S. Global Positioning System (GPS), the Russian Global Navigation Satellite System (GLONASS), the Europe Galileo satellite navigation system and the Chinese BD-1 satellite positioning system. Among these systems, the signal characteristics of GPS and Galileo are good reference to our 2nd satellite navigation system. The improvement of GPS signals is a main aspect of GPS modernization. The aim of GPS modernization is mainly to modernize its signal structure so as to improve the whole systems' performance. The signal structure of Galileo has been revised for several times, and its present signal is the results of long time signal design. From GPS modernization and Galileo signals status, we can summarize some key specifications of navigation signals and some technologies to support these specifications. Based on this, we'll discuss some problems which should be attentive in our country's 2nd satellite navigation system and give some suggestions. This paper is organized into five sections. The first section will give a brief introduction of present satellite navigation system and their main features. Section two will review the GPS and Galileo signals structure evolution, including GPS modernization, Galileo signals status and the comparison of two systems' signals. In the third section, the relationship between signal parameters and system performance will be analyzed, including RF signal characteristics, modulation type, ranging code (such as code type, length and rate) and navigation data. In section four we will discuss some inspiration and technologies concerning our 2nd satellite navigation system, such as the use of multiple frequency signals (ionospheric delay estimation and carrier ambiguity resolution), pilot tones & dataless channel, binary offset carrier (BOC) modulation, and so on. The last section is conclusion, in which the whole paper will be retrospected and some useful conclusion will be given.

Zhu, Xiangwe; Wang, Feixue

2005-11-01

212

Flight test results of a tightly integrated RLG-based Global Positioning System\\/inertial navigation system  

Microsoft Academic Search

Development of a tightly integrated Global Positioning System\\/inertial navigation system (GPS\\/INS) is being pursued following the development of a miniaturized GPS receiver and a compact multiaxis ring laser gyro. The flight test program is reviewed, and the results are discussed in detail. The flight test results showed the excellent performance capabilities of the GPS\\/INS integrated configuration. In a region of

M. F. Lynch; D. J. Weber

1990-01-01

213

GPS 375 (10033807,  

E-print Network

GPS 375 (10033807, ) 38 ` GPS ' : : : : sclab , . , . , , , . : 39 5(2012.5) GPS (An Energy Saving System for Smartphone GPS Sensors Using Bayesian Networks Modeling) (Si-Hyuk Yi) (Sung-Bae Cho) GPS . GPS . GPS , GPS

Cho, Sung-Bae

214

Orion Absolute Navigation System Progress and Challenges  

NASA Technical Reports Server (NTRS)

The Orion spacecraft is being designed as NASA's next-generation exploration vehicle for crewed missions beyond Low-Earth Orbit. The navigation system for the Orion spacecraft is being designed in a Multi-Organizational Design Environment (MODE) team including contractor and NASA personnel. The system uses an Extended Kalman Filter to process measurements and determine the state. The design of the navigation system has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudorange and deltarange, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, pad alignment, cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.

Holt, Greg N.; D'Souza, Christopher

2011-01-01

215

76 FR 33022 - Eighty-Sixth Meeting: RTCA Special Committee 159: Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS) AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS). DATES: The...

2011-06-07

216

75 FR 28318 - Eighty-Second Meeting: RTCA Special Committee 159: Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS) AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS). DATES: The...

2010-05-20

217

75 FR 2581 - Eighty-First Meeting: RTCA Special Committee 159: Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS) AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS). DATES: The...

2010-01-15

218

76 FR 27744 - Eighty-Fifth Meeting: RTCA Special Committee 159: Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS) AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS). DATES: The...

2011-05-12

219

76 FR 67019 - Eighty-Seventh: RTCA Special Committee 159: Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS) AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS) 87th meeting....

2011-10-28

220

75 FR 61818 - Eighty-Third Meeting: RTCA Special Committee 159: Global Positioning System (GPS).  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159: Global Positioning System (GPS). AGENCY: Federal...Committee 159 meeting: Global Positioning System (GPS...Special Committee 159: Global Positioning System (GPS). DATES: The...

2010-10-06

221

77 FR 12106 - 88th Meeting: RTCA Special Committee 159, Global Positioning System (GPS)  

Federal Register 2010, 2011, 2012, 2013

...Special Committee 159, Global Positioning System (GPS) AGENCY: Federal...Special Committee 159, Global Positioning System (GPS...Special Committee 159, Global Positioning System (GPS). DATES: The...

2012-02-28

222

Tight coupling of GPS, laser scanner, and inertial measurements for navigation in urban environments  

Microsoft Academic Search

Many applications can be envisioned for accurate, robust, and reliable navigation solution in challenging urban environments. Examples of existing and prospective applications include, but are not limited to, navigation, guidance, and control of autonomous vehicles (including both ground and aerial vehicles) for urban surveillance and reconnaissance; collection of geographical information system (GIS) data in cities; monitoring of urban infrastructure for

Andrey Soloviev

2008-01-01

223

A blind navigation system using RFID for indoor environments  

Microsoft Academic Search

A location and tracking system becomes very important to our future world of pervasive computing, where information is all around us. Location is one of the most needed information for emerging and future applications. Since the public use of GPS satellite is allowed, several state-of-the-art devices become part of our life, e.g. a car navigator and a mobile phone with

S. Chumkamon; P. Tuvaphanthaphiphat; P. Keeratiwintakorn

2008-01-01

224

A magnetic pulse does not affect homing pigeon navigation: a GPS tracking experiment.  

PubMed

The cues by which homing pigeons are able to return to a home loft after displacement to unfamiliar release sites remain debated. A number of experiments in which migratory birds have been treated with a magnetic pulse have produced a disruption in their orientation, which argues that a ferrimagnetic sense is used for navigation in birds. One previous experiment has also indicated an effect of magnetic pulses on homing pigeon navigation, although with inconsistent results. Previous studies have shown that some magnetic-related information is transmitted by the trigeminal nerve to the brain in some bird species, including the homing pigeon. The function of this information is still unclear. It has been suggested that this information is important for navigation. Previous studies with trigeminal nerve lesioned homing pigeons have clearly shown that the lack of trigeminally mediated information, even if magnetic, is not crucial for homing performance. However, this result does not completely exclude the possibility that other ferrimagnetic receptors in the homing pigeon play a role in navigation. Additionally, recent studies on homing pigeons suggested the existence of a ferrimagnetic sense in a novel location presumably located in the inner ear (lagena). In the present study, we tested whether any ferrimagnetic magnetoreceptors, irrespective of their location in the bird's head, are involved in pigeons' homing. To do this, we treated homing pigeons with a strong magnetic pulse before release, tracked birds with GPS loggers and analyzed whether this treatment affected homing performance. In the single previous magnetic pulse experiment on homing pigeons, only initial orientation at a release site was considered and the results were inconsistent. We observed no effect of the magnetic pulse at any of the sites used on initial orientation, homing performance, tortuosity or track efficiency, which does not support a role for the ferrimagnetic sense in homing pigeon navigation, at least not in this geographic area, where magnetic field variations are in the region of 200 nT intensity and 0.8 deg inclination. PMID:23470658

Holland, Richard; Filannino, Caterina; Gagliardo, Anna

2013-06-15

225

Application of the GPS system for preliminary satellite orbit determination  

Microsoft Academic Search

In this paper, we discuss a method of preliminary orbit determination for an artificial satellite based on the navigation message of the GPS constellation. Orbital elements are considered as state variables and a simple dynamic model, based on the classic two-body problem, is used. The observations are formed by range and range and range-rate with respect to four visible GPS.

A. P. M Chiaradia; S da Silva Fernandes; R. Vilhena de Moraes

1997-01-01

226

Miniaturized GPS/MEMS IMU integrated board  

NASA Technical Reports Server (NTRS)

This invention documents the efforts on the research and development of a miniaturized GPS/MEMS IMU integrated navigation system. A miniaturized GPS/MEMS IMU integrated navigation system is presented; Laser Dynamic Range Imager (LDRI) based alignment algorithm for space applications is discussed. Two navigation cameras are also included to measure the range and range rate which can be integrated into the GPS/MEMS IMU system to enhance the navigation solution.

Lin, Ching-Fang (Inventor)

2012-01-01

227

Theory of inertial navigation systems  

Microsoft Academic Search

The book deals with the theory of semianalytical, analytical, and platformless inertial navigation systems. A one-parameter family of equivalent ellipsoids of revolution (h-ellipsoids, where h stands for height) is introduced, which in the first approximation constitute the equipotential surfaces of the gravity field. The center of mass moves along the surface of an h-ellipsoid (horizontal aircraft flight and ship motion).

P. V. Bromberg

1979-01-01

228

Tightly Coupled Inertial Navigation System/Global Positioning System (TCMIG)  

NASA Technical Reports Server (NTRS)

Many NASA applications planned for execution later this decade are seeking high performance, miniaturized, low power Inertial Management Units (IMU). Much research has gone into Micro-Electro-Mechanical System (MEMS) over the past decade as a solution to these needs. While MEMS devices have proven to provide high accuracy acceleration measurements, they have not yet proven to have the accuracy required by many NASA missions in rotational measurements. Therefore, a new solution has been formulated integrating the best of all IMU technologies to address these mid-term needs in the form of a Tightly Coupled Micro Inertial Navigation System (INS)/Global Positioning System (GPS) (TCMIG). The TCMIG consists of an INS and a GPS tightly coupled by a Kalman filter executing on an embedded Field Programmable Gate Array (FPGA) processor. The INS consists of a highly integrated Interferometric Fiber Optic Gyroscope (IFOG) and a MEMS accelerometer. The IFOG utilizes a tightly wound fiber coil to reduce volume and the high level of integration and advanced optical components to reduce power. The MEMS accelerometer utilizes a newly developed deep etch process to increase the proof mass and yield a highly accurate accelerometer. The GPS receiver consists of a low power miniaturized version of the Blackjack receiver. Such an IMU configuration is ideal to meet the mid-term needs of the NASA Science Enterprises and the new launch vehicles being developed for the Space Launch Initiative (SLI).

Watson, Michael D.; Jackson, Kurt (Technical Monitor)

2002-01-01

229

Fusion of Redundant Autonomous Sensors for Navigation  

E-print Network

) : absolute position Inertial Navigation Systems (INS) : relative position, velocity and orientation Aiding for correcting inertial navigation system positions Accurate filtered trajectory Bad case: What happens if GPS SAMPLING RATE) INERTIAL NAVIGATION SYSTEM POSITIONS (HIGH SAMPLING RATE) TRUE TRAJECTORY FILTERED

230

Legal and Ethical Implications of GPS Vulnerabilities  

Microsoft Academic Search

The Global Positioning System (GPS) has slowly permeated into the civilian community and has become an essential accessory for the modern individual. Various commercial applications heavily rely on GPS technology. GPS has also started receiving attention in court cases, where it has been admissible as evidence leading to convictions or proving innocence. However, GPS is a radio-navigation system and is

Muhammad Usman Iqbal; Samsung Lim

2008-01-01

231

The Open Service Signal in Space Navigation Data Comparison of the Global Positioning System and the BeiDou Navigation Satellite System  

PubMed Central

More and more Global Navigation Satellite Systems (GNSSs) have been developed and are in operation. Before integrating information on various GNSSs, the differences between the various systems must be studied first. This research focuses on analyzing the navigation data differences between the Chinese BeiDou Navigation Satellite System (BDS) and the United States' Global Positioning System (GPS). In addition to explaining the impact caused by these two different coordinate and time systems, this research uses an actual open service signal in space (SIS) for both GPS and BDS to analyze their current system performance. Five data quality analysis (DQA) mechanisms are proposed in this research to validate both systems' SIS navigation data. These five DQAs evaluate the differences in ephemeris and almanac messages from both systems for stability and accuracy. After all of the DQAs, the different issues related to GPS and BDS satellite information are presented. Finally, based on these DQA results, this research provides suggested resolutions for the combined use of GPS and BDS for navigation and guidance. PMID:25195848

Jan, Shau-Shiun; Tao, An-Lin

2014-01-01

232

GPS-Like Phasing Control of the Space Solar Power System Transmission Array.  

National Technical Information Service (NTIS)

The problem of phasing of the Space Solar Power System's transmission array has been addressed by developing a GPS-like radio navigation system. The goal of this system is to provide power transmission phasing control for each node of the array that cause...

M. L. Psiaki

2003-01-01

233

Integrated Inertial/gps  

NASA Technical Reports Server (NTRS)

The presence of failures in navigation sensors can cause the determination of an erroneous aircraft state estimate, which includes position, attitude, and their derivatives. Aircraft flight control systems rely on sensor inputs to determine the aircraft state. In the case of integrated Inertial/NAVSTAR Global Positioning System (GPS), sensor failures could occur in the on-board inertial sensors or in the GPS measurements. The synergistic use of both GPS and the Inertial Navigation System (INS) allows for highly reliable fault detection and isolation of sensor failures. Integrated Inertial/GPS is a promising technology for the High Speed Civil Transport (HSCT) and the return and landing of a manned space vehicle.

Kline, Paul; Vangraas, Frank

1990-01-01

234

A visual navigation system for autonomous flight of micro air vehicles  

Microsoft Academic Search

Many applications of unmanned aerial vehicles (UAVs) require the capability to navigate to some goal and to perform precise and safe landing. In this paper, we present a visual navigation system as an alternative pose estimation method for environments and situations in which GPS is unavailable. The developed visual odometer is an incremental procedure that estimates the vehicle's ego-motion by

Farid Kendoul; Kenzo Nonami

2009-01-01

235

Applying the principle of integrated navigation systems to estimating the motion of large vehicles  

Microsoft Academic Search

Combining inertial sensors and GPS has led to integrated navigation systems of a performance surpassing classical navigation requirements. A utilisation of this technology suggests itself which considers not only the classical movement of a small, rigid body but expands the application range also to large aircraft, space stations and suchlike. The signals generated on this basis are usable both for vehicle

Jörg F Wagner; Günther Kasties

2004-01-01

236

Autonomous navigation system. [gyroscopic pendulum for air navigation  

NASA Technical Reports Server (NTRS)

An inertial navigation system utilizing a servo-controlled two degree of freedom pendulum to obtain specific force components in the locally level coordinate system is described. The pendulum includes a leveling gyroscope and an azimuth gyroscope supported on a two gimbal system. The specific force components in the locally level coordinate system are converted to components in the geographical coordinate system by means of a single Euler transformation. The standard navigation equations are solved to determine longitudinal and lateral velocities. Finally, vehicle position is determined by a further integration.

Merhav, S. J. (inventor)

1981-01-01

237

Global Positioning System (GPS) Bias Correction and Habitat Analysis of  

E-print Network

Global Positioning System (GPS) Bias Correction and Habitat Analysis of Mountain Goats Oreamnos, shall not be allowed without my written permission. Signature Date #12;Global Positioning System (GPS to the difficulties of monitoring animal movement in all months of the year. The use of global positioning system (GPS

Wallin, David O.

238

A VIRTUAL VALIDATION ENVIRONMENT FOR THE DESIGN OF AUTOMOTIVE SATELLITE BASED NAVIGATION SYSTEMS FOR URBAN CANYONS  

Microsoft Academic Search

Satellite based automotive navigation systems use range information to navigation satellites like GPS, Glonas and in the future Galileo to determine their location on earth. Range to satellites is determined by measuring the time dierence between signals send by satellite and received by the automotive navigation system. To determine a 3D-position at sucient accuracy with non-atomic clocks requires receiving at

Holger Rath; Peter Unger; Andreas Emde; David Gruner; Horst Salzwedel

239

Global Positioning System Time Transfer Receiver (GPS/TTR) prototype design and initial test evaluation  

NASA Technical Reports Server (NTRS)

Time transfer equipment and techniques used with the Navigation Technology Satellites were modified and extended for use with the Global Positioning System (GPS) satellites. A prototype receiver was built and field tested. The receiver uses the GPS L1 link at 1575 MHz with C/A code only to resolve a measured range to the satellite. A theoretical range is computed from the satellite ephemeris transmitted in the data message and the user's coordinates. Results of user offset from GPS time are obtained by differencing the measured and theoretical ranges and applying calibration corrections. Results of the first field test evaluation of the receiver are presented.

Oaks, J.; Frank, A.; Falvey, S.; Lister, M.; Buisson, J.; Wardrip, C.; Warren, H.

1982-01-01

240

The MARCOR GPS mobile data system  

NASA Technical Reports Server (NTRS)

Market research revealed several key demands for an Automatic Vehicle Location (AVL) Global Positioning System (GPS) radio. The demands were for minimization of urban building blockage, easy programmability to minimize mobile data transmission costs, high accuracy for street map level coordination, interface capability with non-digital Specialized Mobile Radios (SMR), and a selling price close to that of alternatives such as Signposts and Loran-C. A team of experts was assembled to surmount these challenges and deliver a GPS radio for $500 to $1000, which operates at high accuracy in an urban environment and is plug-compatible with nearly all vehicle radios. Among the engineering and production breakthroughs described here are a unique Simultrac (Trademark) approach to satellite tracking, enabling up to eight GPS satellites to be used for position determination with a 2-channel receiver, and a receiver-in-a-microphone design. A powerful Application Specific Integrated Circuit (ASIC) allowed GPS to be brought within easy reach of millions of AVL users such as bus, taxi, and delivery vehicle fleets.

Rothblatt, Martin

1991-01-01

241

Multirate problems in aided inertial navigation systems  

Microsoft Academic Search

The main principal of navigation systems is the determination of a vehicle's position and velocity relative to some reference coordinate frame. An inertial navigation system (INS) utilizes inertial properties of sensors mounted aboard the vehicle to execute the navigation function. The system accomplishes this task through appropriate processing of the data obtained from acceleration and angular velocity measurements supplied by

Bora Barin; Y. Ozkazanc

2004-01-01

242

MMAS and ACS for GPS Surveying Problem STEFKA FIDANOVA  

E-print Network

1: GPS satellite system 1 Introduction Satellite navigation systems have an impact in geo- science GLObal Navigation Satellite System (GLONASS), and the forthcoming European satellite navigation system [7]. The GPS navigation supports the safe passage of a vessel, aircraft or vehicle from the departure

Fidanova, Stefka

243

Navigation system for flexible endoscopes  

NASA Astrophysics Data System (ADS)

Endoscopic Ultrasound (EUS) features flexible endoscopes equipped with a radial or linear array scanhead allowing high resolution examination of organs adjacent to the upper gastrointestinal tract. An optical system based on fibre-glass or a CCD-chip allows additional orientation. However, 3-dimensional orientation and correct identification of the various anatomical structures may be difficult. It therefore seems desirable to merge real-time US images with high resolution CT or MR images acquired prior to EUS to simplify navigation during the intervention. The additional information provided by CT or MR images might facilitate diagnosis of tumors and, ultimately, guided puncture of suspicious lesions. We built a grid with 15 plastic spheres and measured their positions relatively to five fiducial markers placed on the top of the grid. For this measurement we used an optical tracking system (OTS) (Polaris, NDI, Can). Two sensors of an electromagnetic tracking system (EMTS) (Aurora, NDI, Can) were mounted on a flexible endoscope (Pentax GG 38 UX, USA) to enable a free hand ultrasound calibration. To determine the position of the plastic spheres in the emitter coordinate system of the EMTS we applied a point-to-point registration (Horn) using the coordinates of the fiducial markers in both coordinate systems (OTS and EMTS). For the transformation between EMTS to the CT space the Horn algorithm was adopted again using the fiducial markers. Visualization was enabled by the use of the AVW-4.0 library (Biomedical Imaging Resource, Mayo Clinic, Rochester/MN, USA). To evaluate the suitability of our new navigation system we measured the Fiducial Registration Error (FRE) of the diverse registrations and the Target Registration Error (TRE) for the complete transformation from the US space to the CT space. The FRE for the ultrasound calibration amounted to 4.3 mm +/- 4.2 mm, resulting from 10 calibration procedures. For the transformation from the OTS reference system to the EMTS emitter space we found an average FRE of 0.8 mm +/- 0.2 mm. The FRE for the CT registration was 1.0 mm +/- 0.3 mm. The TRE was found to be 3.8 mm +/- 1.3 mm if we target the same spheres which where used for the calibration procedure. A movement of the phantom results in higher TREs because of the orientation sensitivity of the sensor. In that case the TRE in the area where the biopsy is supposed to be taken place was found to be 7.9 mm +/- 3.2 mm. Our system provides the interventionist with additional information about position and orientation of the used flexible instrument. Additionally, it improves the marksmanship of biopsies. The use of the miniaturized EMTS enables for the first time the navigation of flexible instruments in this way. For the successful application of navigation systems in interventional radiology, an accuracy in the range of 5 mm is desirable. The accuracy of the localization of a point in CT space are just 3 mm too high as required. One of the possibilities to overcome this difference is to mount the two sensors in such a way that the interference of their electromagnetic fields is minimized. A considerable restraint constitutes the small characteristic volume (360mm x 600mm x 600mm), which requires for most application an additional optical system.

Hummel, Johann; Figl, Michael; Birkfellner, Wolfgang; Häfner, Michael; Kollmann, Christian; Bergmann, Helmar

2003-05-01

244

Airborne Antenna System for Minimum-Cycle-Slip GPS Reception  

NASA Technical Reports Server (NTRS)

A system that includes a Global Positioning System (GPS) antenna and associated apparatus for keeping the antenna aimed upward has been developed for use aboard a remote-sensing-survey airplane. The purpose served by the system is to enable minimum- cycle-slip reception of GPS signals used in precise computation of the trajectory of the airplane, without having to restrict the airplane to maneuvers that increase the flight time needed to perform a survey. Cycle slip signifies loss of continuous track of the phase of a signal. Minimum-cycle-slip reception is desirable because maintaining constant track of the phase of the carrier signal from each available GPS satellite is necessary for surveying to centimeter or subcentimeter precision. Even a loss of signal for as short a time as a nanosecond can cause cycle slip. Cycle slips degrade the quality and precision of survey data acquired during a flight. The two principal causes of cycle slip are weakness of signals and multipath propagation. Heretofore, it has been standard practice to mount a GPS antenna rigidly on top of an airplane, and the radiation pattern of the antenna is typically hemispherical, so that all GPS satellites above the horizon are viewed by the antenna during level flight. When the airplane must be banked for a turn or other maneuver, the reception hemisphere becomes correspondingly tilted; hence, the antenna no longer views satellites that may still be above the Earth horizon but are now below the equatorial plane of the tilted reception hemisphere. Moreover, part of the reception hemisphere (typically, on the inside of a turn) becomes pointed toward ground, with a consequent increase in received noise and, therefore, degradation of GPS measurements. To minimize the likelihood of loss of signal and cycle slip, bank angles of remote-sensing survey airplanes have generally been limited to 10 or less, resulting in skidding or slipping uncoordinated turns. An airplane must be banked in order to make a coordinated turn. For small-radius, short-time coordinated turns, it is necessary to employ banks as steep as 45 , and turns involving such banks are times and for confining airplanes as closely as possible to areas to be surveyed. The idea underlying the design is that if the antenna can be kept properly aimed, then the incidence of cycle slips caused by loss or weakness of signals can be minimized. The system includes an articulating GPS antenna and associated electronic circuitry mounted under a radome atop an airplane. The electronic circuitry includes a microprocessor-based interface-circuit-and-data-translation module. The system receives data on the current attitude of the airplane from the inertial navigation system of the airplane. The microprocessor decodes the attitude data and uses them to compute commands for the GPS-antenna-articulating mechanism to tilt the antenna, relative to the airplane, in opposition to the roll or bank of the airplane to keep the antenna pointed toward the zenith. The system was tested aboard the hurricane- hunting airplane of the National Oceanic and Atmospheric Administration (NOAA) [see figure] during an 11-hour flight to observe the landfall of Hurricane Bret in late summer of 1999. No bank-angle restrictions were imposed during the flight. Post-flight analysis of the GPS trajectory data revealed that no cycle slip had occurred.considered normal maneuvers. These steep banks are highly desirable for minimizing flight

Wright, C. Wayne

2009-01-01

245

Performance of Hybrid Positioning System Combining GPS and Television Signals  

Microsoft Academic Search

In spite of the global coverage and the penetration into a daily life of GPS (global positioning system), GPS receivers have not been able to overcome the critical weakness of a GPS signal in indoor and urban areas due to its low signal power level after a long journey from satellites. One of the best solutions to this problem is

Matthew Rabinowitz; P. Enge

2006-01-01

246

The Evolution of Global Positioning System (GPS) Technology.  

ERIC Educational Resources Information Center

Describes technological advances in the Global Positioning System (GPS), which is also known as the NAVSTAR GPS satellite constellation program developed in 1937, and changes in the nature of our world by GPS in the areas of agriculture, health, military, transportation, environment, wildlife biology, surveying and mapping, space applications, and…

Kumar, Sameer; Moore, Kevin B.

2002-01-01

247

NAVSTAR GPS Simulation and Analysis Program.  

National Technical Information Service (NTIS)

This study assesses the capability of the planned NAVSTAR Global Positioning System (GPS) to meet civil navigation requirements. When it becomes operational in about 1983, NAVSTAR GPS will provide accurate two-dimensional and three-dimensional service to ...

J. Kraemer, J. Vilcans, N. Knable, R. M. Kalafus

1983-01-01

248

Vision-Based Estimation for Guidance, Navigation, and  

E-print Network

modality for aircraft navigation, researchers have been motivated to investigate other navigational sensor/collaborative sensor to GPS systems. Cameras can act as navigational sensors by detecting and tracking feature points System (GPS) is the primary navigational sensor modality used for vehicle guidance, navigation

Dixon, Warren

249

Autonomous navigation system and method  

DOEpatents

A robot platform includes perceptors, locomotors, and a system controller, which executes instructions for autonomously navigating a robot. The instructions repeat, on each iteration through an event timing loop, the acts of defining an event horizon based on the robot's current velocity, detecting a range to obstacles around the robot, testing for an event horizon intrusion by determining if any range to the obstacles is within the event horizon, and adjusting rotational and translational velocity of the robot accordingly. If the event horizon intrusion occurs, rotational velocity is modified by a proportion of the current rotational velocity reduced by a proportion of the range to the nearest obstacle and translational velocity is modified by a proportion of the range to the nearest obstacle. If no event horizon intrusion occurs, translational velocity is set as a ratio of a speed factor relative to a maximum speed.

Bruemmer, David J. (Idaho Falls, ID) [Idaho Falls, ID; Few, Douglas A. (Idaho Falls, ID) [Idaho Falls, ID

2009-09-08

250

ION GPS '99, 14-17 September 1999, Nashville, TN Testing a GPS-based System for the Support of  

E-print Network

ION GPS '99, 14-17 September 1999, Nashville, TN Testing a GPS-based System for the Support of Ship as research professional on the GPS OTF project within the GEOIDE Network of Centres of Excellence of Geomatic Sciences at Laval University, where he conducts research and teaching in precise GPS static

Santerre, Rock

251

The GPS Class: Global Positioning Systems, Map, and Compass  

NSDL National Science Digital Library

This portal provides access to lessons and information about using Global Positioning Systems (GPS) in education. Materials include ideas for teaching and using GPS in educational curricula; websites, books, and other tools; and information on how to set up and use a GPS reciever. There is also information about setting up and using a compass with a topographic map and on converting GPS coordinates for use within a Geographic Information System (GIS). A section on Geocaching and Earthcaching provides tips on how to incorporate GPS treasure hunts into educational curricula and learning about Earth's environment and processes. Sample Geocaching courses are included.

252

Environmental applications of GPS  

SciTech Connect

The use of the Global Positioning System (GPS) has revolutionized air travel, ocean navigation, land navigation, and the collection of environmental data. Although a basic civilian GPS receiver can be purchased for as little as $100, the receiver is only the tip of a 12 billion dollar iceberg. This paper will discuss the history and basic operation of the Global Positioning System, a satellite-based precision positioning and timing service developed and operated by the Department of Defense. It will also describe the accuracy limitations of the civil GPS service and how accuracy can be enhanced by the use of differential GPS (DGPS), using either the free National Differential GPS system, or commercial differential monitor stations. Finally, the paper will discuss the future accuracy upgrades of civil GPS as a result of recent federal policy decisions.

Vigil, S.A.; Zueck, D.

1999-07-01

253

A wellbore inertial navigation system  

SciTech Connect

A prototype wireline tool which includes a downhole inertial platform and a surface computer to spatially map a well is described. The hardware consists of a single-gimballed inertial platform with accelerometers and gyros to obtain three-axis motion information. The gyroscope and accelerometer outputs are transmitted to a computer at the surface which calculates probe attitude relative to north, east, and vertical. Double integration of the accelerometer data provides the position information. A conventional 7-conductor wireline is used for the system data transmission. System accuracy is enhanced by advances made in the computer software which processes the data received from the tool. The software uses statistical sampling estimation to obtain optimal estimates of the system errors. Measurement errors are determined by periodically stopping the tool during the logging procedure and observing the indicated velocity measurements. This procedure, known as Kalman filtering, results in increased accuracy of the data. Present mapping systems have an X-Y-Z location accuracy of 100 to 200 feet for a typical well depth of 10,000 feet. Test results show that the new system is accurate to about 1 foot per 1000 feet of well depth. Unlike conventional systems, the inertial navigator does not require any sort of projection of the cable length (which may not be accurately known). Also, this system provides continuous data throughout the wellbore and logging speeds on the order of 10 ft/sec appear possible. The hardware and software associated with this mapping system are described and the recent field test results are reported.

Kelsey, J.R.

1983-02-01

254

Inertial navigation system intelligent diagnostic expert (INSIDE)  

Microsoft Academic Search

A troubleshooting expert system has been designed to provide repair and diagnostic information for aircraft inertial navigation systems (INS). The inertial navigation system intelligent diagnostic expert (INSIDE) is used to diagnose faults in an INS system, and to train new operators on the troubleshooting of an INS system, thus freeing up the experienced engineer for other projects. INSIDE leads a

L. Attias; J. Sveitis

1990-01-01

255

Application of the GPS system for preliminary satellite orbit determination  

NASA Astrophysics Data System (ADS)

In this paper, we discuss a method of preliminary orbit determination for an artificial satellite based on the navigation message of the GPS constellation. Orbital elements are considered as state variables and a simple dynamic model, based on the classic two-body problem, is used. The observations are formed by range and range and range-rate with respect to four visible GPS. A discrete Kalman filter with simulated data is used as filtering technique. The data are obtained through numerical propagation (Cowell's method), which considers special perturbations for the GPS satellite constellation and a user satellite.

Chiaradia, A. P. M.; da Silva Fernandes, S.; de Moraes, R. Vilhena

256

PLANS '84 - Position Location and Navigation Symposium, San Diego, CA, November 26-29, 1984, Record  

NASA Astrophysics Data System (ADS)

Questions regarding the applications and equipment of the Global Positioning System (GPS) are discussed, taking into account the use of differential GPS positioning for geodetic applications, the use of Synchromesh for the practical enhancement of GPS service, the synergism of the Global Positioning System and electronic terrain map systems, position location with the NBS/GPS time transfer system, early applications of civil GPS, service outages in GPS associated with satellite failures, precise positioning using a four-channel C/A code GPS receiver, and differential GPS marine navigation. Other topics explored are related to radio navigation systems, mapping and charting, geodesy, the GPS development, strapdown inertial navigation, federal radionavigation policy, marine navigation, aircraft navigation, and the positioning, stabilization, and pointing of space systems. Attention is given to an evaluation of radionavigation systems, control moment gyros for the Space Shuttle, the impact of GPS on ocean surveying, and Kalman filter designs for integrated marine navigation systems.

257

Precision navigation for aerospace applications  

E-print Network

Navigation is important in a variety of aerospace applications, and commonly uses a blend of GPS and inertial sensors. In this thesis, a navigation system is designed, developed, and tested. Several alternatives are ...

Stimac, Andrew K. (Andrew Kenneth), 1977-

2004-01-01

258

12.215 Modern Navigation, Fall 2002  

E-print Network

Introduces the concepts and applications of navigation techniques using celestial bodies and satellite positioning systems such as the Global Positioning System (GPS). Topics include astronomical observations, radio ...

Herring, T. (Thomas)

259

GPS: A New Constellation  

NSDL National Science Digital Library

This Air and Space Museum website provides detailed information about how GPS (Global Positioning System) works. Beginning with technology that existed before GPS, such as the sextant and the TRANSIT satellite, it provides information about land, air, and sea navigation, Earth mapping, land management, and scientific applications.

2008-09-03

260

Precise point positioning with the BeiDou navigation satellite system.  

PubMed

By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS) around the World. The Position and Navigation Data Analyst (PANDA) software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP). The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems. PMID:24406856

Li, Min; Qu, Lizhong; Zhao, Qile; Guo, Jing; Su, Xing; Li, Xiaotao

2014-01-01

261

Precise Point Positioning with the BeiDou Navigation Satellite System  

PubMed Central

By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS) around the World. The Position and Navigation Data Analyst (PANDA) software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP). The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems. PMID:24406856

Li, Min; Qu, Lizhong; Zhao, Qile; Guo, Jing; Su, Xing; Li, Xiaotao

2014-01-01

262

In-flight detection of errors for enhanced aircraft flight safety and vertical accuracy improvement using digital terrain elevation data with an inertial navigation system, global positioning system and radar altimeter  

Microsoft Academic Search

This dissertation discusses integration architectures using digital terrain elevation data (DTED) with an inertial navigation system (INS), a global positioning system (GPS) and a radar altimeter. Two integration architectures are considered: DTED with INS, GPS and radar altimeter for aircraft vertical accuracy improvement during the final approach; and DTED with kinematic GPS (KGPS) and a radar altimeter for enhanced aircraft

Robert Anthony Gray

1999-01-01

263

Enhanced Navigation System for Road Telematics  

Microsoft Academic Search

Navigation systems are becoing standard in-vehicle\\u000a equipment. In the future these technologies will take\\u000a place in new systems called Intelligent Integrated Road\\u000a Safety Systems. Reaching this high level of integration\\u000a and these requirements needs more precise digital map\\u000a databases and advanced navigation technologies.

Gilliéron Pierre-Yves; Konnen Jeff

2003-01-01

264

Basic Mars Navigation System For Local Areas  

NASA Astrophysics Data System (ADS)

Introduction: This project has been first set up as a basic solution in navigation during EVA (extra-vehicular activities) in the Mars Society Desert Research Station in the desert of Utah. The main idea is to keep the system as simple as possible so that it can be easily adaptable and portable. The purpose of such a device is to tell the astronauts in EVA where they roughly are and then letting them reaching different points in avoiding any risky way. Thus the precision needed has not to be really high: even if it is about 50m, every astronaut can then look on a map and be able to design a way to another point. This navigation system will improve the safety of the EVA as it is an added reliable orientating tool. Concept: To look at a simple way to localize oneself, one should have a look at what has been done by mankind on Earth. Today, everyone can think of the GPS because it's simple and very reliable. However the infrastructure for such a system is huge and will not be for sure available during the first missions. We can think of course of a basic GPS using the satellites being in orbit but this approach is not yet as simple as we would like. If we want to keep the sky in sight, we can use the stars and the moons of Mars. Yet this would be a good solution and we can even have a star tracker that would give a good position according to the time of the picture. This solution has to be kept in mind but a star tracker is quite big for an astronaut without any rover nearby and using the sky may not be as precise as one should expect. Another useful tool is the compass. It has been used for centuries by sailors but on Mars, without a good magnetic field for this purpose. But sailors also use lighthouses and some placemarks on the land to localize themselves. This is done with a compass, measuring the angle between a placemark and the magnetic North. With two angles, we can then have the position of the boat. The idea here is the same: measuring the angles between different placemarks so that we can compute the position. But which placemarks? We have to think about something that can be installed on Mars and is light enough to be brought there. Balloons are really light, and in order to place them, we need a gas as helium (or hydrogen) and also some rope. Hydrogen is likely to be produced in situ and rope will be useful for astronauts. So we started on a concept with some balloons around the base, with different colors or patterns. The crew in EVA can thus know where the base is every time they are in sight of a balloon and with at least three balloons; they can compute their position according to the base. Procedure of the test: During EVA, the astronauts will measure the angle between the different balloons. The balloons are high in the sky so they can be seen far from their location. This is particularly important on Mars where the horizon is nearer than on Earth. The balloons have different colors so they can be identified and we can even think of adding an autonomous colored light under so they can be observed during the night. With good quality balloons, we can keep them in the sky for a few days without maintenance. Angle measurement is done thanks to a camera. A numeric camera can have a precision of less than 0.01°/pixel, which is enough for our application. The distance between the different balloons can easily be seen in a free picture management software and a Matlab tool is under development for this. An algorithm is then run and it gives the positions that fit with the observations on a map. Simulation gave areas 20m width, which is enough for the astronaut who has a map. The exact precision will be investigated in situ, at the MDRS. For this first test bench, computations will be manually done on a computer in order to validate the concept without huge development. Afterwards, one can imagine an implementation on a PDA brought by the astronauts. This PDA would have its own camera so the process can be fully automatic. Such a system can also implement other navigation system as a Martian GPS or a radio locali

Petitfils, E.-A.; Boche-Sauvan, L.; Foing, B. H.; Monaghan, E.; Crews, Eurogeomars

2009-04-01

265

Design and Development of a Real-Time DSP and FPGA-Based Integrated GPS-INS System for Compact and Low Power Applications  

Microsoft Academic Search

Emphasis of the present work is on an elegant real-time solution for GPS\\/INS integration. Micro-electro mechanical system (MEMS) based inertial sensors are light but not accurate enough for inertial navigation system (INS) applications. An integrated INS\\/GPS system provides better accuracy compared with either INS or GPS, used individually. This paper describes an improved design and fabrication of a loosely coupled

V. Agarwal; H. Arya; S. Bhaktavatsala

2009-01-01

266

Quantifying Improvements from the Integration of GPS and a Tactical Grade INS in High  

E-print Network

of satellite and inertial navigation since that time. Some of his past research includes integration of GPS on the integration of GPS and inertial navigation systems for precise aircraft positioning. Dr. Cannon is a Past. INTRODUCTION The integration of Global Positioning System (GPS) receivers with Inertial Navigation Systems (INS

Calgary, University of

267

Inertial/multisensor navigation  

NASA Technical Reports Server (NTRS)

A Multisensor Navigation System as proposed by the Ohio University Avionics Engineering Center is illustrated. The proposed system incorporates radio (Lorac-C), satellite (Global Positioning System) and an inertial navigation system (INS). The inertial part of the system will be of a low grade since the INS will be used primarily for filtering the GPS data and for short term stability. Loran-C and GPS will be used for long term stability.

Alikiotis, Dimitri

1987-01-01

268

Comparison of robust H ? filter and Kalman filter for initial alignment of inertial navigation system  

Microsoft Academic Search

There are many filtering methods that can be used for the initial alignment of an integrated inertial navigation system. This\\u000a paper discussed the use of GPS, but focused on two kinds of filters for the initial alignment of an integrated strapdown inertial\\u000a navigation system (SINS). One method is based on the Kalman filter (KF), and the other is based on

Yan-Ling Hao; Ming-Hui Chen; Liang-Jun Li; Bo Xu

2008-01-01

269

A Recommendation on SLR Ranging to Future Global Navigation Satellite Systems  

Microsoft Academic Search

The multi-agency US Geodetic Requirements Working Group has recommended that Satellite Laser Retro- reflectors be installed on GPS III satellites as a principal component of the Positioning, Navigation, and Timing mandate of the Global Positioning System. The Working Group, which includes NASA, NGA, NOAA, NRL, USGS, and the USNO, echoes the Global Geodetic Observing System recommendation that SLR retro- reflectors

J. L. Labrecque; J. J. Miller; M. Pearlman

2008-01-01

270

The development of a SAR dedicated navigation system: from scratch to the first test flight  

Microsoft Academic Search

In this paper, the authors propose to describe the development process of a navigation system, concerning synthetic aperture radar (SAR) applications, starting from the motivation for the sensor selection and finalizing with the first flight-test results. Sensor selection was one of the first steps in the design. Motivations for the accelerometers, gyroscopes, Global Positioning System (GPS) board, magnetometer and all

J. F. M. Lorga; W. van Rossum; E. van Halsema; Q. P. Chu; J. A. Mulder

2004-01-01

271

General GPS Antenna Information APPLICATION NOTE  

E-print Network

General GPS Antenna Information APPLICATION NOTE #12;Global Positioning System and Precise Time & Frequency The Global Positioning System (GPS) is a worldwide radio-navigation system formed from a constellation of 24 satellites that continuously orbit the earth. Each GPS satellite has on board several atomic

Berns, Hans-Gerd

272

Bayesian Surface and Underwater Navigation Rickard Karlsson and Fredrik Gustafsson, Member IEEE  

E-print Network

, as a supplement to satellite navigation based on the global positioning system (GPS). The proposed Bayesian the global positioning system (GPS). For critical navigation applications, this sensor cannot be the only

Gustafsson, Fredrik

273

U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--STANDARD OPERATING PROCEDURE FOR OPERATION AND INITIALIZATION OF THE MAGELLAN GPS SATELLITE NAVIGATOR (UA-F-22.1)  

EPA Science Inventory

The purpose of this SOP is to describe the general procedures for the operation and initialization of the Magellan Global Positioning System (GPS) Satellite Navigator. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the Borde...

274

Validation on flight data of a closed-loop approach for GPS-based relative navigation of LEO satellites  

NASA Astrophysics Data System (ADS)

This paper describes a carrier-phase differential GPS approach for real-time relative navigation of LEO satellites flying in formation with large separations. These applications are characterized indeed by a highly varying number of GPS satellites in common view and large ionospheric differential errors, which significantly impact relative navigation performance and robustness. To achieve high relative positioning accuracy a navigation algorithm is proposed which processes double-difference code and carrier measurements on two frequencies, to fully exploit the integer nature of the related ambiguities. Specifically, a closed-loop scheme is proposed in which fixed estimates of the baseline and integer ambiguities produced by means of a partial integer fixing step are fed back to an Extended Kalman Filter for improving the float estimate at successive time instants. The approach also benefits from the inclusion in the filter state of the differential ionospheric delay in terms of the Vertical Total Electron Content of each satellite. The navigation algorithm performance is tested on actual flight data from GRACE mission. Results demonstrate the effectiveness of the proposed approach in managing integer unknowns in conjunction with Extended Kalman Filtering, and that centimeter-level accuracy can be achieved in real-time also with large separations.

Tancredi, U.; Renga, A.; Grassi, M.

2013-05-01

275

Optimum Reset of Ship's Inertial Navigation System  

Microsoft Academic Search

Optimum linear filter and control theory is applied to the practical problem of supplementing an inertial navigation system with discrete reference information. The information takes the form of position obtained from Loran C or Decca, for example, and occasional azimuth fixes obtained from star sightings. In particular, optimum use of this information is discussed for the Ship's Inertial Navigation System

B. E. Bona; Robert J. Smay

1966-01-01

276

Inertial navigation system aided by aircraft dynamics  

Microsoft Academic Search

In this work the possibility of using the model of aircraft dynamics as a means for aiding an inertial navigation system is studied. The method is of particular interest for low-grade inertial navigating system (INS). The aiding formulation is introduced, its corresponding mathematical model is derived and used in the design of an appropriate extended Kalman filter. Sensitivity analysis of

M. Koifman; I. Y. Bar-Itzhack

1999-01-01

277

Application of GPS attitude determination to gravity gradient stabilized spacecraft  

Microsoft Academic Search

Recent advances in the Global Positioning System (GPS) technology have initiated a new era in aerospace navigation and control. GPS receivers have become increasingly compact and affordable, and new developments have made attitude determination using subcentimeter positioning among two or more antennas feasible for real-time applications. GPS-based attitude control systems will become highly portable packages which provide time, navigation, and

E. G. Lightsey; Clark E. Cohen; Bradford W. Parkinson

1993-01-01

278

Development of a GPS-aided motion measurement, pointing, and stabilization system for a Synthetic Aperture Radar. [Global Positioning System (GPS)  

SciTech Connect

An advanced Synthetic Aperture Radar Motion Compensation System has been developed by Sandia National Laboratories (SNL). The system includes a miniaturized high accuracy ring laser gyro inertial measurement unit, a three axis gimbal pointing and stabilization assembly, a differential Global Positioning System (GPS) navigation aiding system, and a pilot guidance system. The system provides several improvements over previous SNL motion compensation systems and is capable of antenna stabilization to less than 0.01 degrees RMS and absolute position measurement to less than 5.0 meters RMS. These accuracies have been demonstrated in recent flight testing aboard a DHC-6-300 Twin Otter'' aircraft.

Fellerhoff, J.R.; Kohler, S.M.

1991-01-01

279

GENESIS: GPS Environmental and Earth Science Information System  

NASA Technical Reports Server (NTRS)

This presentation reviews the GPS ENvironmental and Earth Science Information System (GENESIS). The objectives of GENESIS are outlined (1) Data Archiving, searching and distribution for science data products derived from Space borne TurboRogue Space Receivers for GPS science and other ground based GPS receivers, (2) Data browsing using integrated visualization tools, (3) Interactive web/java-based data search and retrieval, (4) Data subscription service, (5) Data migration from existing GPS archived data, (6) On-line help and documentation, and (7) participation in the WP-ESIP federation. The presentation reviews the products and services of Genesis, and the technology behind the system.

Hajj, George

1999-01-01

280

Autonomous navigation system using a fuzzy adaptive nonlinear h? filter.  

PubMed

Although nonlinear H? (NH?) filters offer good performance without requiring assumptions concerning the characteristics of process and/or measurement noises, they still require additional tuning parameters that remain fixed and that need to be determined through trial and error. To address issues associated with NH? filters, a new SINS/GPS sensor fusion scheme known as the Fuzzy Adaptive Nonlinear H? (FANH?) filter is proposed for the Unmanned Aerial Vehicle (UAV) localization problem. Based on a real-time Fuzzy Inference System (FIS), the FANH? filter continually adjusts the higher order of the Taylor development thorough adaptive bounds  and adaptive disturbance attenuation , which significantly increases the UAV localization performance. The results obtained using the FANH? navigation filter are compared to the NH? navigation filter results and are validated using a 3D UAV flight scenario. The comparison proves the efficiency and robustness of the UAV localization process using the FANH? filter. PMID:25244587

Outamazirt, Fariz; Li, Fu; Yan, Lin; Nemra, Abdelkrim

2014-01-01

281

Autonomous Navigation System Using a Fuzzy Adaptive Nonlinear H? Filter  

PubMed Central

Although nonlinear H? (NH?) filters offer good performance without requiring assumptions concerning the characteristics of process and/or measurement noises, they still require additional tuning parameters that remain fixed and that need to be determined through trial and error. To address issues associated with NH? filters, a new SINS/GPS sensor fusion scheme known as the Fuzzy Adaptive Nonlinear H? (FANH?) filter is proposed for the Unmanned Aerial Vehicle (UAV) localization problem. Based on a real-time Fuzzy Inference System (FIS), the FANH? filter continually adjusts the higher order of the Taylor development thorough adaptive bounds (?i) and adaptive disturbance attenuation (?), which significantly increases the UAV localization performance. The results obtained using the FANH? navigation filter are compared to the NH? navigation filter results and are validated using a 3D UAV flight scenario. The comparison proves the efficiency and robustness of the UAV localization process using the FANH? filter. PMID:25244587

Outamazirt, Fariz; Li, Fu; Yan, Lin; Nemra, Abdelkrim

2014-01-01

282

A combined GPS satellite\\/pseudolite system for Category III precision landing  

Microsoft Academic Search

This paper presents the results of a computer simulation, which models a combined GPS, satellite\\/pseudolite navigation system for precision landing. The goal of this system is to meet the CAT III requirements exploiting a combined system of satellites\\/pseudolites under severe geometry, weather, and jamming conditions. The simulation includes the aircraft position\\/velocity estimation and probability of false alarm and misdetection utilizing

Ilir F. Progri; William R. Michalson

2002-01-01

283

GPS Signal-in-Space Integrity Performance Evolution in the  

E-print Network

, Fellow, IEEE Stanford University Knowledge of the Global Positioning System (GPS) signal-in-space (SIS Global Positioning System (GPS) is so far the most widely used space-based positioning, navigation

Stanford University

284

Time and Frequency Measurements Using the Global Positioning System (GPS)  

Microsoft Academic Search

This paper describes how Global Positioning System (GPS) satellite signals are used in time and frequency metrology. It discusses how a GPS receiver can provide a reference signal for frequency calibrations and time synchronization. It also explains the several types of time and frequency measurements that utilize GPS signals. These include one-way or direct reception measurements, single and multi-channel common-view

Michael A. Lombardi; Lisa M. Nelson; Andrew N. Novick; Victor S. Zhang

285

Analysis of navigation performance for the Earth Observing System (EOS) using the TDRSS Onboard Navigation System (TONS)  

NASA Technical Reports Server (NTRS)

Use of the Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (TONS) was proposed as an alternative to the Global Positioning System (GPS) for supporting the Earth Observing System (EOS) mission. The results are presented of EOS navigation performance evaluation with respect to TONS based orbit, time, and frequency determination (OD/TD/FD). Two TONS modes are considered: one uses scheduled TDRSS forward link service to derive one way Doppler tracking data for OD/FD support (TONS-I); the other uses an unscheduled navigation beacon service (proposed for Advanced TDRSS) to obtain pseudorange and Doppler data for OD/TD/FD support (TONS-II). Key objectives of the analysis were to evaluate nominal performance and potential sensitivities, such as suboptimal tracking geometry, tracking contact scheduling, and modeling parameter selection. OD/TD/FD performance predictions are presented based on covariance and simulation analyses. EOS navigation scenarios and the contributions of principal error sources impacting performance are also described. The results indicate that a TONS mode can be configured to meet current and proposed EOS position accuracy requirements of 100 and 50 m, respectively.

Elrod, B.; Kapoor, A.; Folta, David C.; Liu, K.

1991-01-01

286

Applications of GPS technology in the land transportation system  

Microsoft Academic Search

The global positioning system (GPS) allows the accurate positioning of an object using satellite signals. There are a lot of applications of this technology in many scientific fields all over the world. In recent years, the rapid increase in the development of the geographic information system technology (GIS) has led to the development of GPS\\/GIS applications. Therefore, the geometric and

G. Mintsis; S. Basbas; P. Papaioannou; C. Taxiltaris; I. N. Tziavos

2004-01-01

287

Ultra-Wideband Tracking System Design for Relative Navigation  

NASA Technical Reports Server (NTRS)

This presentation briefly discusses a design effort for a prototype ultra-wideband (UWB) time-difference-of-arrival (TDOA) tracking system that is currently under development at NASA Johnson Space Center (JSC). The system is being designed for use in localization and navigation of a rover in a GPS deprived environment for surface missions. In one application enabled by the UWB tracking, a robotic vehicle carrying equipments can autonomously follow a crewed rover from work site to work site such that resources can be carried from one landing mission to the next thereby saving up-mass. The UWB Systems Group at JSC has developed a UWB TDOA High Resolution Proximity Tracking System which can achieve sub-inch tracking accuracy of a target within the radius of the tracking baseline [1]. By extending the tracking capability beyond the radius of the tracking baseline, a tracking system is being designed to enable relative navigation between two vehicles for surface missions. A prototype UWB TDOA tracking system has been designed, implemented, tested, and proven feasible for relative navigation of robotic vehicles. Future work includes testing the system with the application code to increase the tracking update rate and evaluating the linear tracking baseline to improve the flexibility of antenna mounting on the following vehicle.

Ni, Jianjun David; Arndt, Dickey; Bgo, Phong; Dekome, Kent; Dusl, John

2011-01-01

288

Optimum Integration of Aircraft Navigation Systems  

Microsoft Academic Search

A current problem in aircraft navigation is determining how to effect alow cost navigation system consistent with required mission operationswhich will render a high degree of accuracy and reliability. One wayto achieve this is through optimum integration of equipment,subsystems, and computer mechanizations. Consistent with this approach,the overall objectives of this paper are to show the advantages of anoptimally integrated aircraft

William Zimmerman

1969-01-01

289

Rip current monitoring using GPS buoy system  

NASA Astrophysics Data System (ADS)

The occurrence of rip current in the Haeundae beach, which is one of the most famous beaches in South Korea, has been threatening beach-goers security in summer season annually. Many coastal scientists have been investigating rip currents by using field observations and measurements, laboratory measurements and wave tank experiments, and computer and numerical modeling. Rip current velocity is intermittent and may rapidly increase within minutes due to larger incoming wave groups or nearshore circulation instabilities. It is important to understand that changes in rip current velocity occur in response to changes in incoming wave height and period as well as changes in water level. GPS buoys have been used to acquire sea level change data, atmospheric parameters and other oceanic variables in sea for the purposes of vertical datum determination, tide correction, radar altimeter calibration, ocean environment and marine pollution monitoring. Therefore, we adopted GPS buoy system for an experiment which is to investigate rip current velocity; it is sporadic and may quickly upsurge within minutes due to larger arriving wave groups or nearshore flow uncertainties. In this study, for high accurate positioning of buy equipment, a Satellite Based Argumentation System DGPS data logger was deployed to investigate within floating object, and it can be acquired three-dimensional coordinate or geodetic position of buoy with continuous NMEA-0183 protocol during 24 hours. The wave height measured by in-situ hydrometer in a cross-shore array clearly increased before and after occurrence of rip current, and wave period also was lengthened around an event. These results show that wave height and period correlate reasonably well with long-shore current interaction in the Haeundae beach. Additionally, current meter data and GPS buoy data showed that rip current velocities, about 0.2 m/s, may become dangerously strong under specific conditions. Acknowledgement This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology(2010-0024670)

Song, DongSeob; Kim, InHo; Kang, DongSoo

2014-05-01

290

Study of the global positioning system for maritime concepts/applications: Study of the feasibility of replacing maritime shipborne navigation systems with NAVSTAR  

NASA Technical Reports Server (NTRS)

A geostationary reference satellite (REFSAT) that broadcasts every four seconds updated GPS satellite coordinates was developed. This procedure reduces the complexity of the GPS receiver. The economic and performance payoffs associated with replacing maritime stripborne navigation systems with NAVSTAR was quantified and the use of NAVSTAR for measurements of ocean currents in the broad ocean areas of the world was evaluated.

Winn, C. B.; Huston, W.

1981-01-01

291

A method for authentication of the GPS transmitter  

Microsoft Academic Search

The activities related to IRNSS (Indian Regional Navigational Satellite System) are at the peak at this time. It includes the integration of GPS, GNSS (Global Navigational Satellite System) and Galileo navigational systems. The single chip solution looks at integrating the RF\\/IF block with the digital signal processing block on a single chip. Such solutions invoke the possibilities of integrating GPS

Prarthan D. Mehta

2009-01-01

292

Gravity aided inertial navigation system (GAINS)  

NASA Astrophysics Data System (ADS)

The paper describes a new autonomous covert INS uniquely suited to underwater applications. Unlike the conventional INS, schuler and siderial errors are bounded without external navigation aids or active instrumentation of ground speed. As a result, the system exhibits excellent long-term navigation performance while maintaining the inherent covertness of the INS system. A conventional INS is integrated with a gravity gradiometer capable of measuring gravity field components independently of platform accelerations. This new integration scheme takes advantage of navigation system velocity error observability. Parametric performance results are presented for GAINS, varying gyro, gravimeter, gradiometer, depth sensor quality, and gravity field activity.

Jircitano, Albert; Dosch, Daniel E.

293

Proceedings of 2011 NSF Engineering Research and Innovation Conference, Atlanta, Georgia Grant #0927475 Integration of Global Positioning System and Inertial Navigation for  

E-print Network

#0927475 Integration of Global Positioning System and Inertial Navigation for Ubiquitous Context on the integration of Real Time Kinematic Global Positioning System (RTK-GPS) and Personal Dead Reckoning (PDR

Kamat, Vineet R.

294

System using leo satellites for centimeter-level navigation  

NASA Technical Reports Server (NTRS)

Disclosed herein is a system for rapidly resolving position with centimeter-level accuracy for a mobile or stationary receiver [4]. This is achieved by estimating a set of parameters that are related to the integer cycle ambiguities which arise in tracking the carrier phase of satellite downlinks [5,6]. In the preferred embodiment, the technique involves a navigation receiver [4] simultaneously tracking transmissions [6] from Low Earth Orbit Satellites (LEOS) [2] together with transmissions [5] from GPS navigation satellites [1]. The rapid change in the line-of-sight vectors from the receiver [4] to the LEO signal sources [2], due to the orbital motion of the LEOS, enables the resolution with integrity of the integer cycle ambiguities of the GPS signals [5] as well as parameters related to the integer cycle ambiguity on the LEOS signals [6]. These parameters, once identified, enable real-time centimeter-level positioning of the receiver [4]. In order to achieve high-precision position estimates without the use of specialized electronics such as atomic clocks, the technique accounts for instabilities in the crystal oscillators driving the satellite transmitters, as well as those in the reference [3] and user [4] receivers. In addition, the algorithm accommodates as well as to LEOS that receive signals from ground-based transmitters, then re-transmit frequency-converted signals to the ground.

Rabinowitz, Matthew (Inventor); Parkinson, Bradford W. (Inventor); Cohen, Clark E. (Inventor); Lawrence, David G. (Inventor)

2002-01-01

295

Automatic GPS-based vehicle tracking and localization information system  

Microsoft Academic Search

The convergence of GPS technologies, wireless communications, and Internet is seen as the key to the GPS consumer market. The proposed vehicle tracking and localization system allows: remote and mobile control and vehicle monitoring (position and velocity) via SMS commands and answers; passenger voice notification when vehicle get near to next railway or bus station, actual arrival and scheduled time,

Rosen Ivanov

2003-01-01

296

The Role of Trust and Interaction in GPS Related Accidents: A Human Factors Safety Assessment of the Global Positioning System (GPS)  

E-print Network

of the Global Positioning System (GPS) Chris. W. Johnson, DPhil; Department of Computing Science, University; accident analysis; organisational safety. Abstract The Global Positioning System (GPS) uses a network

Johnson, Chris

297

A comparative analysis of area navigation systems for general aviation  

E-print Network

Within the next decade area navigation is to become the primary method of air navigation within the United States. There are numerous radio navigation systems that offer the capabilities of area navigation to general ...

Dodge, Steven Malcolm

1973-01-01

298

Orion Absolute Navigation System Progress and Challenge  

NASA Technical Reports Server (NTRS)

The absolute navigation design of NASA's Orion vehicle is described. It has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary onboard measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudo-range and delta-range, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, and cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.

Holt, Greg N.; D'Souza, Christopher

2012-01-01

299

It's a long way to Monte Carlo: Probabilistic display in GPS John Williamson1  

E-print Network

, GPS-based multimodal navigation system, equipped with inertial control that allows users to explore. We demonstrate a probabilistic approach to navigation using a combination of GPS and general inertialIt's a long way to Monte Carlo: Probabilistic display in GPS navigation John Williamson1 1

Williamson, John

300

Jose Angel AVILA RODRIGUEZ: Interference of Galileo with other systems in the L1 and L5 bands: Interoperability with GPS and Degradation due to the ARNS  

E-print Network

Jose Angel AVILA RODRIGUEZ: Interference of Galileo with other systems in the L1 and L5 bands radio navigation, known as Galileo, to be developed in three proposed phases: · Development systems, i.e. GPS and Glonass. #12;Galileo, the first satellite positioning and navigation system

Schuh, Harald

301

Bluetooth Navigation System using Wi-Fi Access Points  

E-print Network

There have been various navigation and tracking systems being developed with the help of technologies like GPS, GSM, Bluetooth, IR, Wi-Fi and Radar. Outdoor positioning systems have been deployed quite successfully using GPS but positioning systems for indoor environments still do not have widespread deployment due to various reasons. Most of these use only a single technology for positioning but using more than one in cooperation with each other is always advantageous for obtaining greater accuracy. Particularly, the ones which use Bluetooth are better since they would enhance the scalability of such a system because of the fact that this technology is in use by the common people so it would always be easy to track them. Moreover it would also reduce the hardware installation cost to some extent. The system that has been introduced here uses Bluetooth primarily for positioning and tracking in combination with Wi-Fi access points. The reason that makes the commercial application of such a system easier and ch...

Agrawal, Rohit

2012-01-01

302

New vision system and navigation algorithm for an autonomous ground vehicle  

NASA Astrophysics Data System (ADS)

Improvements were made to the intelligence algorithms of an autonomously operating ground vehicle, Q, which competed in the 2013 Intelligent Ground Vehicle Competition (IGVC). The IGVC required the vehicle to first navigate between two white lines on a grassy obstacle course, then pass through eight GPS waypoints, and pass through a final obstacle field. Modifications to Q included a new vision system with a more effective image processing algorithm for white line extraction. The path-planning algorithm adopted the vision system, creating smoother, more reliable navigation. With these improvements, Q successfully completed the basic autonomous navigation challenge, finishing tenth out of over 50 teams.

Tann, Hokchhay; Shakya, Bicky; Merchen, Alex C.; Williams, Benjamin C.; Khanal, Abhishek; Zhao, Jiajia; Ahlgren, David J.

2013-12-01

303

Pattern Acquisition Technology for Semiconductor Navigation System  

Microsoft Academic Search

A semiconductor navigation system based on Scanning Electron Microscope has been developed to fast locate the smallest defects which can bring wafer production to a waster. The mainly parts of the navigation system are pattern acquisition model and scanning model. The pattern acquisition model is made up of an Analog-to-Digital Convertor, a CPLD and a Static RAM. The electron-beam is

Wei Liu; Bohua Yin

2008-01-01

304

The GPS Space Service Volume  

NASA Technical Reports Server (NTRS)

Prior to the advent of artificial satellites, the concept of navigating in space and the desire to understand and validate the laws of planetary and satellite motion dates back centuries. At the initiation of orbital flight in 1957, space navigation was dominated by inertial and groundbased tracking methods, underpinned by the laws of planetary motion. It was early in the 1980s that GPS was first explored as a system useful for refining the position, velocity, and timing (PVT) of other spacecraft equipped with GPS receivers. As a result, an entirely new GPS utility was developed beyond its original purpose of providing PVT services for land, maritime, and air applications. Spacecraft both above and below the GPS constellation now receive the GPS signals, including the signals that spill over the limb of the Earth. The use of radionavigation satellite services for space navigation in High Earth Orbits is in fact a capability unique to GPS. Support to GPS space applications is being studied and planned as an important improvement to GPS. This paper discusses the formalization of PVT services in space as part of an overall GPS improvement effort. It describes the GPS Space Service Volume (SSV) and compares it to the Terrestrial Service Volume (TSV). It also discusses SSV coverage with the current GPS constellation, coverage characteristics as a function of altitude, expected power levels, and coverage figures of merit.

Bauer, F. H.; Moreau, M. C.; Dahle-Melsaether, M. E.; Petrofski, W. P.; Stanton, B. J.; Thomason, S.; Harris, G. A.; Sena, R. P.; Temple, L. Parker, III

2006-01-01

305

Limitations of Pseudolite Systems Using Off-The-Shelf GPS Receivers  

Microsoft Academic Search

Pseudolites (PLs) are ground-based transmitters that transmit GPS-like signals. They have been used to test GPS system elements and to enhance GPS in certain applications by providing better accuracy, integrity and availability through the use of PL signals in addition to the GPS signals. PLs are also a promising technology for providing positioning in indoor, high multipath environments where GPS

Mustafa Ozgur Kanli

2004-01-01

306

Sigma-point Kalman filtering for integrated GPS and inertial navigation  

Microsoft Academic Search

A sigma-point Kalman filter is derived for integrating GPS measurements with inertial measurements from gyros and accelerometers to determine both the position and the attitude of a moving vehicle. Sigma-point filters use a carefully selected set of sample points to more accurately map the probability distribution than the linearization of the standard extended Kalman filter (KKF), leading to faster convergence

J. L. Crassidis

2006-01-01

307

Discussion of GPS Anti-Jam Technology  

Microsoft Academic Search

  The Global Positioning System (GPS) satellita navigation aiding system, sometimes called NAVSTAR, has become a utility to\\u000a the military and many civilian areas. GPS, currently consisting of 24 satellites, is used by the military for navigation,\\u000a precision weapons delivery, and the future digital battlefield. In the civilian sector, GPS is widely used as the primary\\u000a or secondary aid for land,

Mario M. Casabona; Murray W. Rosen

1999-01-01

308

Inertial navigation system for bladder endoscopy.  

PubMed

The usage of video endoscopes in cystoscopic interventions of the urinary bladder impedes an intuitive navigation. Although image-based solutions such as panorama images can provide extended views of the surgical field, a real-time 3-D navigation is not supported. Furthermore, the integration of common tracking systems in ambulant clinics is often hindered due to low usability and high costs. Thus, we discuss in this paper a first low-cost inertial navigation system. Our evaluation results show that in spite of lower sensor accuracies, mean errors between < 1° and 4° are achieved for solid angles. Using endoscopes with different view angles we apply an extended endoscope model for an adaptive displacement correction. Furthermore, we implement a first guided navigation tool for tumor re-identification in real-time. PMID:22255553

Behrens, Alexander; Grimm, Jonathan; Gross, Sebastian; Aach, Til

2011-01-01

309

Color night vision system for ground vehicle navigation  

NASA Astrophysics Data System (ADS)

Operating in a degraded visual environment due to darkness can pose a threat to navigation safety. Systems have been developed to navigate in darkness that depend upon differences between objects such as temperature or reflectivity at various wavelengths. However, adding sensors for these systems increases the complexity by adding multiple components that may create problems with alignment and calibration. An approach is needed that is passive and simple for widespread acceptance. Our approach uses a type of augmented display to show fused images from visible and thermal sensors that are continuously updated. Because the raw fused image gave an unnatural color appearance, we used a color transfer process based on a look-up table to replace the false colors with a colormap derived from a daytime reference image obtained from a public database using the GPS coordinates of the vehicle. Although the database image was not perfectly registered, we were able to produce imagery acquired at night that appeared with daylight colors. Such an approach could improve the safety of nighttime navigation.

Ali, E. A.; Qadir, H.; Kozaitis, S. P.

2014-06-01

310

GPS-based satellite tracking system for precise positioning  

NASA Technical Reports Server (NTRS)

NASA is developing a Global Positioning System (GPS) based measurement system to provide precise determination of earth satellite orbits, geodetic baselines, ionospheric electron content, and clock offsets between worldwide tracking sites. The system will employ variations on the differential GPS observing technique and will use a network of nine fixed ground terminals. Satellite applications will require either a GPS flight receiver or an on-board GPS beacon. Operation of the system for all but satellite tracking will begin by 1988. The first major satellite application will be a demonstration of decimeter accuracy in determining the altitude of TOPEX in the early 1990's. By then the system is expected to yield long-baseline accuracies of a few centimeters and instantaneous time synchronization to 1 ns.

Yunck, T. P.; Melbourne, W. G.; Thornton, C. L.

1985-01-01

311

Hybrid GPS-GSM Localization of Automobile Tracking System  

E-print Network

An integrated GPS-GSM system is proposed to track vehicles using Google Earth application. The remote module has a GPS mounted on the moving vehicle to identify its current position, and to be transferred by GSM with other parameters acquired by the automobile's data port as an SMS to a recipient station. The received GPS coordinates are filtered using a Kalman filter to enhance the accuracy of measured position. After data processing, Google Earth application is used to view the current location and status of each vehicle. This goal of this system is to manage fleet, police automobiles distribution and car theft cautions.

Al-Khedher, Mohammad A

2012-01-01

312

Accurate aircraft wind measurements using the global positioning system (GPS)  

SciTech Connect

High accuracy measurements of the spatial distribution of wind speed are required in the study of turbulent exchange between the atmosphere and the earth. The use of a differential global positioning system (GPS) to determine the sensor velocity vector component of wind speed is discussed in this paper. The results of noise and rocking testing are summarized, and fluxes obtained from the GPS-based methods are compared to those measured from systems on towers and airplanes. The GPS-based methods provided usable measurements that compared well with tower and aircraft data at a significantly lower cost. 21 refs., 1 fig., 2 tabs.

Dobosy, R.J.; Crawford, T.L., McMillen, R.T., Dumas, E.J. [Atmospheric Turbulence and Diffusion Div., Oak Ridge, TN (United States)

1996-11-01

313

Advanced Development of ESG Strapdown Navigation Systems  

Microsoft Academic Search

The fundamental problem of inertial navigation, double integration of acceleration to obtain position, is defined and discussed. Mechanizations of both space-stable and local-vertical platform systems are exhibited. The synthesis problem for an electrically suspended gyro (ESG) strapdown system is defined and discussed: readout, readout errors due to vehicle motion, synchronization of readout with system computer, alignment, correction and calibration for

T. W. Christensen

1966-01-01

314

The Mathematics of Navigating the Solar System  

NASA Technical Reports Server (NTRS)

In navigating spacecraft throughout the solar system, the space navigator relies on three academic disciplines - optimization, estimation, and control - that work on mathematical models of the real world. Thus, the navigator determines the flight path that will consume propellant and other resources in an efficient manner, determines where the craft is and predicts where it will go, and transfers it onto the optimal trajectory that meets operational and mission constraints. Mission requirements, for example, demand that observational measurements be made with sufficient precision that relativity must be modeled in collecting and fitting (the estimation process) the data, and propagating the trajectory. Thousands of parameters are now determined in near real-time to model the gravitational forces acting on a spacecraft in the vicinity of an irregularly shaped body. Completing these tasks requires mathematical models, analyses, and processing techniques. Newton, Gauss, Lambert, Legendre, and others are justly famous for their contributions to the mathematics of these tasks. More recently, graduate students participated in research to update the gravity model of the Saturnian system, including higher order gravity harmonics, tidal effects, and the influence of the rings. This investigation was conducted for the Cassini project to incorporate new trajectory modeling features in the navigation software. The resulting trajectory model will be used in navigating the 4-year tour of the Saturnian satellites. Also, undergraduate students are determining the ephemerides (locations versus time) of asteroids that will be used as reference objects in navigating the New Millennium's Deep Space 1 spacecraft autonomously.

Hintz, Gerald

2000-01-01

315

A computer system for geosynchronous satellite navigation  

NASA Astrophysics Data System (ADS)

A computer system specifically designed to estimate and predict Geostationary Operational Environmental Satellite (GOES-4) navigation parameters using Earth imagery is described. The estimates are needed for spacecraft maneuvers while prediction provide the capability for near real-time image registration. System software is composed of four functional subsystems: (1) data base management; (2) image processing; (3) navigation; and (4) output. Hardware consists of a host minicomputer, a cathode ray tube terminal, a graphics/video display unit, and associated input/output peripherals. System validity is established through the processing of actual imagery obtained by sensors on board the Synchronous Meteorological Satellite (SMS-2). Results indicate the system is capable of operationally providing both accurate GOES-4 navigation estimates and images with a potential registration accuracy of several picture elements (pixels).

Koch, D. W.

1980-12-01

316

Navigation of robotic system using cricket motes  

NASA Astrophysics Data System (ADS)

This paper presents a novel algorithm for self-mapping of the cricket motes that can be used for indoor navigation of autonomous robotic systems. The cricket system is a wireless sensor network that can provide indoor localization service to its user via acoustic ranging techniques. The behavior of the ultrasonic transducer on the cricket mote is studied and the regions where satisfactorily distance measurements can be obtained are recorded. Placing the motes in these regions results fine-grain mapping of the cricket motes. Trilateration is used to obtain a rigid coordinate system, but is insufficient if the network is to be used for navigation. A modified SLAM algorithm is applied to overcome the shortcomings of trilateration. Finally, the self-mapped cricket motes can be used for navigation of autonomous robotic systems in an indoor location.

Patil, Yogendra J.; Baine, Nicholas A.; Rattan, Kuldip S.

2011-06-01

317

Flight-control/navigation inertial reference system  

NASA Technical Reports Server (NTRS)

The preliminary design of a redundant strapdown navigation system for integrated flight-control/navigation use has been completed. Based on application of tuned-gimbal gyros, a compact configuration (13 in x 13 in x 14 in) has been achieved for fail-operational/fail-operational redundancy. Test data are presented for strapdown system test programs including flight testing of the LN-50 tuned-gimbal gyro system. Testing of a redundant sensor configuration is currently in process. Strapdown gyro development also includes ring laser and nuclear magnetic resonance techniques.

Ebner, R. E.

1977-01-01

318

Inertial navigation sensor integrated obstacle detection system  

NASA Technical Reports Server (NTRS)

A system that incorporates inertial sensor information into optical flow computations to detect obstacles and to provide alternative navigational paths free from obstacles. The system is a maximally passive obstacle detection system that makes selective use of an active sensor. The active detection typically utilizes a laser. Passive sensor suite includes binocular stereo, motion stereo and variable fields-of-view. Optical flow computations involve extraction, derotation and matching of interest points from sequential frames of imagery, for range interpolation of the sensed scene, which in turn provides obstacle information for purposes of safe navigation.

Bhanu, Bir (Inventor); Roberts, Barry A. (Inventor)

1992-01-01

319

Significance of Waterway Navigation Positioning Systems On Ship's Manoeuvring Safety  

NASA Astrophysics Data System (ADS)

The main goal of navigation is to lead the ship to the point of destination safety and efficiently. Various factors may affect ship realisating this process. The ship movement on waterway are mainly limited by water area dimensions (surface and depth). These limitations cause the requirement to realise the proper of ship movement trajectory. In case when this re requirement cant't fulfil then marine accident may happend. This fact is unwanted event caused losses of human health and life, damage or loss of cargo and ship, pollution of natural environment, damage of port structures or blocking the port of its ports and lost of salvage operation. These losses in same cases can be catas- trophical especially while e.i. crude oil spilling could be place. To realise of safety navigation process is needed to embrace the ship's movement trajectory by waterways area. The ship's trajectory is described by manoeuvring lane as a surface of water area which is require to realise of safety ship movement. Many conditions affect to ship manoeuvring line. The main are following: positioning accuracy, ship's manoeuvring features and phenomena's of shore and ship's bulk common affecting. The accuracy of positioning system is most important. This system depends on coast navigation mark- ing which can range many kinds of technical realisation. Mainly used systems based on lights (line), radionavigation (local system or GPS, DGPS), or radars. If accuracy of positiong is higer, then safety of navigation is growing. This article presents these problems exemplifying with approaching channel to ports situated on West Pomera- nian water region.

Galor, W.

320

A GPS System-of-Systems for Science  

NASA Astrophysics Data System (ADS)

The 2006 National Research Council (NRC) Decadal Report will stress that future directions for Earth science at NASA/NOAA will focus on achievement of a national strategy for the Earth Sciences that balances international economic competitiveness, protection of life and property, and stewardship of the planet for this and future generations. Because of the urgent need for climate measurements identified in the report, a small group from JPL was formed to explore the science benefits of maintaining GPS receivers in orbit for climate science. This is a particularly timely topic since 7 new GPS-science capable satellites were launched in 2006 (COSMIC 1-6, MetOp1), resulting in 10 GPS-science capable satellites in orbit (including CHAMP, SAC-C, GRACE). For this GPS System-of-Systems, we studied climate observations, ionosphere observations, and ocean science. For climate observations, we simulated a constellation of ten satellites in a configuration similar to COSMIC, and performed a multi-year analysis of how such a constellation would be able to characterize long-term trends in temperature. We find that such a constellation is adequate to compute zonally-averaged, monthly mean temperatures with a precision adequate to address expected climate trends of order ~0.1 K per decade. Such a constellation also has adequate local time coverage to avoid aliasing diurnal cycle trends with global climate trends. The high accuracy and consistency of GPS-based atmospheric retrievals suggests that continuously maintaining an operating constellation of such receivers is an important global observation asset for characterizing long-term climate trends. We also performed a series of simulations to determine the science returns that could be achieved with varying sizes of GPS receiver constellations. This study can be used to consider the advantages of including GPS science receivers on future satellites as dedicated constellations or constellations of opportunity. For ocean science, we assumed each satellite would be equipped with a Toga receiver (now in development under NASA's Instrument Incubator Program), and a steerable 20-dB gain antenna with field of view capable of intercepting all available reflections. The conclusions drawn from this study are as follows: - For atmospheric science, a constellation of 9 satellites in reasonably diverse orbits is enough to satisfy anticipated requirements for climate observations. This can be done with either a dedicated constellation (such as COSMIC) or a constellation of opportunity, which could be formed by placing GPS receivers on all new NASA satellites. - For ionospheric science, the near-term, 10-satellite constellation is sufficient to produce major advances in our understanding of space-weather dynamics and to characterize the global conductivity structure of the ionosphere. An even larger constellation would benefit studies of smaller-scale structures in the ionosphere, such as occur at high latitudes during aurora. - For ocean/ice science, a constellation of six satellites equipped for processing ocean and ice reflections would satisfy basic needs. We would encourage in-space testing of the next generation Toga receiver as soon as possible after its completion in 2008, to validate the instrument and demonstrate the benefits of GPS ocean reflection science. If that flight test is successful, a constellation of six GPS receivers could be built up to perform ocean/ice science.

Sherwood, R.; Mannucci, A.; Zuffada, C.; Heeg, C.

2006-12-01

321

Inertial navigation system for mobile land vehicles  

Microsoft Academic Search

This paper describes a prototype of an inertial navigation system for use in mobile land vehicles, such as cars or mobile robots. The complete system is composed by sensors, their mechanical mount and cabling, these connect to a PC card with local processing and memory, based on a Intel 80C196KC microcontroller. The sensors used were a piezoelectric vibrating gyroscope, two

Jorge Lobo; Paulo Lucas; Jorge Dias; A. Traca de Almeida

1995-01-01

322

Checking of communications and radio navigation systems  

Microsoft Academic Search

The testing of aircraft communications and radio navigation systems is addressed. Limited assessments need to take account of variations in ground station performance, and uncertainty regarding radio wave propagation conditions. Antenna performance can vary markedly in different aircraft to affect the radial coverage of all systems, or the accuracy achieved by direction finding equipment. Aircraft transmitting antenna characteristics can be

H. Maidment

1980-01-01

323

GPS RISK ASSESSMENT STUDY FINAL REPORT  

E-print Network

-based system using signals provided by the Department of Defense's Global Positioning System (GPS). However-jam technologies. KEYWORDS: National Airspace System Global Positioning System Navigation #12;v TABLE OF CONTENTS

Ladkin, Peter B.

324

NTNU Java: How GPS works  

NSDL National Science Digital Library

This applet describes and demonstrates how GPS works. The Global Positioning System (GPS) is actually a constellation of 27 Earth-orbiting satellites (24 in operation and three extras in case one fails)implemented by the U.S. military for military navigation.

Hwang, Fu-Kwun

2008-07-07

325

Obstacle-avoiding navigation system  

DOEpatents

A system for guiding an autonomous or semi-autonomous vehicle through a field of operation having obstacles thereon to be avoided employs a memory for containing data which defines an array of grid cells which correspond to respective subfields in the field of operation of the vehicle. Each grid cell in the memory contains a value which is indicative of the likelihood, or probability, that an obstacle is present in the respectively associated subfield. The values in the grid cells are incremented individually in response to each scan of the subfields, and precomputation and use of a look-up table avoids complex trigonometric functions. A further array of grid cells is fixed with respect to the vehicle form a conceptual active window which overlies the incremented grid cells. Thus, when the cells in the active window overly grid cell having values which are indicative of the presence of obstacles, the value therein is used as a multiplier of the precomputed vectorial values. The resulting plurality of vectorial values are summed vectorially in one embodiment of the invention to produce a virtual composite repulsive vector which is then summed vectorially with a target-directed vector for producing a resultant vector for guiding the vehicle. In an alternative embodiment, a plurality of vectors surrounding the vehicle are computed, each having a value corresponding to obstacle density. In such an embodiment, target location information is used to select between alternative directions of travel having low associated obstacle densities.

Borenstein, Johann (Ann Arbor, MI); Koren, Yoram (Ann Arbor, MI); Levine, Simon P. (Ann Arbor, MI)

1991-01-01

326

Abstract--This paper presents novel Global Navigation Satellite System (GNSS)-based flight inspection systems  

E-print Network

, and integrity. The GNSS-based FIS are the WAAS-based FIS and the stand-alone GPS-based FIS. These GNSS-based FIS requires raw GPS/WAAS measurements, and the stand-alone GPS requires only raw GPS measurements. Both systems require a radar altimeter and a TeleVision Positioning System (TVPS) for CAT II and III

Stanford University

327

Observability studies of inertial navigation systems  

NASA Technical Reports Server (NTRS)

The present work deals with an undamped three-channel inertial-navigation-system error model. It is shown that it is possible to fully observe, and thus estimate, all the states of the system. This is in contrast to a previous two-channel system, in which it was impossible to fully observe and estimate all the states of the system. The conclusions of the analysis are verified through covariance simulation, which yields identical results.

Bar-Itzhack, I. Y.; Goshen-Meskin, D.

1989-01-01

328

GPS surveys for cross-country transmission systems  

SciTech Connect

This paper describes the Global Positioning System (GPS) in a general way. This brief knowledge is then used to explain and illustrate how the GPS satellites can be used to very precisely survey the centerline of a cross-country transmission line route. The techniques to accomplish the work are explained. The reason for the use of precise surveys is clarified and the way in which the resultant surveys may be integrated with CADD is discussed.

Korgan, R.A. [Willbros Butler Engineers, Inc., Tulsa, OK (United States)

1994-12-31

329

Navigation in Antarctica Today: The Global Positioning System  

NSDL National Science Digital Library

After researching how the Global Positioning System is used in Antarctica and across the globe, students learn how GPS works. Throughout this weeklong activity, students collect their findings in a portfolio. The comprehensive curriculum materials contain teacher tools, which include individually downloadable readings, detailed daily breakdowns of tasks, teacher strategies for using the activities, a portfolio grading sheet, a project rubric sheet, and additional readings. Students investigate the use of the Global Positioning System (GPS)in Antarctica and across the globe. They conduct research on the Web to understand how and why GPS is used today. Students also complete a hands-on activity that is based on spatial principles similar to those used by GPS; they learn how GPS works by doing on paper the work of GPS satellites in space.

330

A study on the PRN ranging code of satellite navigation systems  

NASA Astrophysics Data System (ADS)

The pseudo random noise ranging code has been applied extensively to spread spectrum communications. Currently most satellite navigation systems utilize the spread spectrum communication technology to transmit navigation information, and the commonly-used PRN ranging code is the balanced Gold code. In this paper, the characteristics and producing approach of the balanced Gold code are studied, and the balance of the coarse/acquisition code of GPS (global positioning system) is analyzed. Finally the results of the corresponding simulation on the platform of System View are presented. This study can be used for reference in the related work.

Lu, Xiao-Chun; Chen, Qing-Gang; Hu, Yong-Hui

2004-06-01

331

Exploitation of Semantic Building Model in Indoor Navigation Systems  

NASA Astrophysics Data System (ADS)

There are many types of indoor and outdoor navigation tools and methodologies available. A majority of these solutions are based on Global Positioning Systems (GPS) and instant video and image processing. These approaches are ideal for open world environments where very few information about the target location is available, but for large scale building environments such as hospitals, governmental offices, etc the end-user will need more detailed information about the surrounding context which is especially important in case of people with special needs. This paper presents a smart indoor navigation solution that is based on Semantic Web technologies and Building Information Model (BIM). The proposed solution is also aligned with Google Android's concepts to enlighten the realization of results. Keywords: IAI IFCXML, Building Information Model, Indoor Navigation, Semantic Web, Google Android, People with Special Needs 1 Introduction Built environment is a central factor in our daily life and a big portion of human life is spent inside buildings. Traditionally the buildings are documented using building maps and plans by utilization of IT tools such as computer-aided design (CAD) applications. Documenting the maps in an electronic way is already pervasive but CAD drawings do not suffice the requirements regarding effective building models that can be shared with other building-related applications such as indoor navigation systems. The navigation in built environment is not a new issue, however with the advances in emerging technologies like GPS, mobile and networked environments, and Semantic Web new solutions have been suggested to enrich the traditional building maps and convert them to smart information resources that can be reused in other applications and improve the interpretability with building inhabitants and building visitors. Other important issues that should be addressed in building navigation scenarios are location tagging and end-user communication. The available solutions for location tagging are mostly based on proximity sensors and the information are bound to sensor references. In the proposed solution of this paper, the sensors simply play a role similar to annotations in Semantic Web world. Hence the sensors data in ontology sense bridges the gap between sensed information and building model. Combining these two and applying the proper inference rules, the building visitors will be able to reach their destinations with instant support of their communication devices such as hand helds, wearable computers, mobiles, etc. In a typical scenario of this kind, user's profile will be delivered to the smart building (via building ad-hoc services) and the appropriate route for user will be calculated and delivered to user's end-device. The calculated route is calculated by considering all constraints and requirements of the end user. So for example if the user is using a wheelchair, the calculated route should not contain stairs or narrow corridors that the wheelchair does not pass through. Then user starts to navigate through building by following the instructions of the end-device which are in turn generated from the calculated route. During the navigation process, the end-device should also interact with the smart building to sense the locations by reading the surrounding tags. So for example when a visually impaired person arrives at an unknown space, the tags will be sensed and the relevant information will be delivered to user in the proper way of communication. For example the building model can be used to generate a voice message for a blind person about a space and tell him/her that "the space has 3 doors, and the door on the left should be chosen which needs to be pushed to open". In this paper we will mainly focus on automatic generation of semantic building information models (Semantic BIM) and delivery of results to the end user. Combining the building information model with the environment and user constraints using Semantic Web technologies will make many scenarios conceivable. The gen

Anjomshoaa, A.; Shayeganfar, F.; Tjoa, A. Min

2009-04-01

332

Multiposition alignment of strapdown inertial navigation system  

Microsoft Academic Search

The authors demonstrate that the stationary alignment of strapdown inertial navigation system (SDINS) can be improved by employing the multiposition\\/technique. Using an observability analysis, it is shown that an optimal two-position alignment not only satisfies complete observability conditions but also minimizes alignment errors. This is done by analytic rank testing of the stripped observability matrix and numerical calculation of the

J. G. Lee; C. G. Park; H. W. Park

1993-01-01

333

Design of gyroscope-free navigation systems  

Microsoft Academic Search

We examine the feasibility of designing a gyroscope-free inertial navigation system (INS) that uses only accelerometers to compute the linear and angular motions of a rigid body. The accelerometer output equation is derived to relate the linear and angular motions of a rigid body relative to a fixed inertial frame. A sufficient condition is given to determine if a configuration

Chin-Woo Tan; K. Mostov; P. Varaiya

2001-01-01

334

Peformance limits for multiplatform scene-referenced navigation systems  

Microsoft Academic Search

The accuracy of aircraft\\/weapon navigation systems has improved dramatically since the introduction of global positioning systems and terrain-referenced navigation systems into integrated navigation suites. Future improvements, in terms of reliability and accuracy, could arise from the inclusion of navigation systems based on the correlation of known ground features with imagery from a visual band or infrared sensor, often called scene

Jason F. Ralph; Eleanor M. Januarius; Moira I. Smith; Kenneth L. Edwards; Mark Bernhardt

2001-01-01

335

A Review of Multisensor Fusion Methodologies for Aircraft Navigation Systems  

Microsoft Academic Search

This paper reviews currently existing fault-tolerant navigation system architectures and data fusion methods used in the design and development of integrated aircraft navigation systems and also compares their advantages and disadvantages. Four fault-tolerant navigation system architectures are reviewed and the associated Kalman filter architectures and algorithms are discussed. These techniques have been used in most integrated aircraft navigation systems. The

David J. Allerton; Huamin Jia

2005-01-01

336

The Magnavox civil and military line of GPS receivers - A technology and applications overview  

Microsoft Academic Search

Eleven different GPS receivers are described, including both military and commercial versions for land, sea, and air navigation. The receivers cover applications including geodetic land surveying, differential navigation with and without pseudolites, parachute descent navigation, and GPS integrated with an inertial navigation system. The receiver configurations range from complete packages to original equipment manufacturer modules.

Thomas A. Stansell Jr.

1987-01-01

337

Autonomous Navigation and Exploration of a Quadrotor Helicopter in GPS-denied Indoor Environments  

Microsoft Academic Search

This paper presents our solution for enabling a quadrotor helicopter to autonomously navigate, explore and locate objects of interest in unstructured and unknown indoor environments. We describe the de- sign and operation of our quadrotor helicopter, before presenting the software architecture and individual algorithms necessary for executing the mission. Experimental results are presented demonstrating the quadrotor's ability to operate autonomously

Markus Achtelik; Abraham Bachrach; Ruijie He; Samuel Prentice; Nicholas Roy

338

OMEGA navigation system status and future plans  

NASA Technical Reports Server (NTRS)

OMEGA is described as a very low frequency (VLF) radio navigational system operating in the internationally allocated navigation band in the electromagentic spectrum between 10 and 14 kilohertz. Full system implementation with worldwide coverage from eight transmitting stations is planned for the latter 1970's. Experimental stations have operated since 1966 in support of system evaluation and test. These stations provided coverage over most of the North Atlantic, North American Continent, and eastern portions of the North Pacific. This coverage provided the fundamental basis for further development of the system and has been essential to the demonstrated feasibility of the one to two nautical mile root-mean-square system accuracy. OMEGA is available to users in all nations, both on ships and in aircraft.

Nolan, T. P.; Scull, D. C.

1974-01-01

339

An advanced system for performance evaluation of integrated navigation systems  

Microsoft Academic Search

This paper focuses on a prototypical test system aimed at estimating field performance of integrated aircraft navigation systems. Assumed design requirements for the navigation system are cm-level positioning accuracy and absolute attitude estimation error in dynamic conditions of the order of 0.1° at most. Since performance estimation does not require real time operation, the test system is based on offline

Giancarmine Fasano; Alfredo Renga; Domenico Accardo; Michele Grassi; Roberto Senatore

2011-01-01

340

Abstract-The use of satellite aided navigation in the modern transport sector is well established worldwide. Air and sea  

E-print Network

is about 12 sidereal hours (~11 hours, 58 minutes)[3]. Fig 1 GPS Constellation III .GPS Segments GPS and reliable position information.GPS is one of the greatest EM application that is used tom locate objects any where of the world I.INTRODUCTION The Global Positioning System (GPS) is a satellite-based navigation

Masoudi, Husain M.

341

Satellite Navigation Systems: Policy, Commercial and Technical Interaction.  

NASA Astrophysics Data System (ADS)

This book adopts a broad perspective on positioning and navigation systems which rely on Earth orbiting satellites for their successful operation. The first of such global systems was the US Global Positioning System (GPS), and the next the Russian GLONASS system. Now studies relating to Europe's future Galileo system are gaining momentum and other nations are planning regional augmentation systems. All such systems are discussed here, particularly relating to political, commercial, legal and technical issues. The opportunities - and also the problems - of having three similar systems in operation simultaneously are examined, and several novel applications are proposed. These range from improved vehicular transport by land, sea and air, to more accurate surveying, more efficient agricultural practices and safer operations in mountainous regions. Everyone who is challenged by these topics will find this volume invaluable. ISU WWW Server; http://www.isunet.edu. Further information on ISU Symposia may also be obtained by e-mail from symposium@isu.isunet.edu Link: http://www.wkap.nl/prod/b/1-4020-1678-6

Rycroft, M.

2003-12-01

342

GPS Problem Math21a, 2003-2008 The global positioning system GPS uses the fact that a receiver can get the differ-  

E-print Network

GPS Problem Math21a, 2003-2008 The global positioning system GPS uses the fact that a receiver can get the differ- ence of distances to two satellites. Each GPS satellite sends periodically signals is in general the set of points for which these distances match? Conclude that we can determine the GPS receiver

Knill, Oliver

343

Fully integrated CMOS GPS receiver for system-on-chip solutions  

Microsoft Academic Search

A CMOS receiver for the Global Positioning System (GPS) is presented. It is designed in a 0.13mum standard CMOS process and is fully integrated for the needs of a system-on-chip (SoC) solution for GPS and assisted GPS (A-GPS). It provides the needed frequency conversion, gain and filtering for GPS signals without any other external components than those required for matching

Christian Grewing; Bo Bokinge; Wenche Einerman; Anders Emericks; Detlev Theil; Stefan van Waasen

2006-01-01

344

Meta-image navigation augmenters for unmanned aircraft systems (MINA for UAS)  

NASA Astrophysics Data System (ADS)

GPS is a critical sensor for Unmanned Aircraft Systems (UASs) due to its accuracy, global coverage and small hardware footprint, but is subject to denial due to signal blockage or RF interference. When GPS is unavailable, position, velocity and attitude (PVA) performance from other inertial and air data sensors is not sufficient, especially for small UASs. Recently, image-based navigation algorithms have been developed to address GPS outages for UASs, since most of these platforms already include a camera as standard equipage. Performing absolute navigation with real-time aerial images requires georeferenced data, either images or landmarks, as a reference. Georeferenced imagery is readily available today, but requires a large amount of storage, whereas collections of discrete landmarks are compact but must be generated by pre-processing. An alternative, compact source of georeferenced data having large coverage area is open source vector maps from which meta-objects can be extracted for matching against real-time acquired imagery. We have developed a novel, automated approach called MINA (Meta Image Navigation Augmenters), which is a synergy of machine-vision and machine-learning algorithms for map aided navigation. As opposed to existing image map matching algorithms, MINA utilizes publicly available open-source geo-referenced vector map data, such as OpenStreetMap, in conjunction with real-time optical imagery from an on-board, monocular camera to augment the UAS navigation computer when GPS is not available. The MINA approach has been experimentally validated with both actual flight data and flight simulation data and results are presented in the paper.

Òªelik, Koray; Somani, Arun K.; Schnaufer, Bernard; Hwang, Patrick Y.; McGraw, Gary A.; Nadke, Jeremy

2013-05-01

345

Autonomous integrated navigation method based on the strapdown inertial navigation system and Lidar  

NASA Astrophysics Data System (ADS)

An integrated navigation method based on the strapdown inertial navigation system (SINS) and Doppler Lidar was presented and its validity is demonstrated by practical experiments. A very effective and independent integrated navigation mode is realized that both an inertial navigation system (INS) and Lidar are not interfered with or screened by electromagnetic waves. In our work, the SINS error model was first introduced, and the velocity error model was transformed into body reference coordinates. Then the expression for measurement model of SINS/Lidar integrated navigation was deduced under Lidar reference coordinates. For application of land or vehicle navigation, the expression for the measurement model was simplified, and observation analysis was carried out. Finally, numerical simulation and vehicle test results were carried out to validate the availability and utility of the proposed SINS/Lidar integrated navigation method for land navigation.

Zhang, Xiaoyue; Lin, Zhili; Zhang, Chunxi

2014-07-01

346

GPS water level measurements for Indonesia's Tsunami Early Warning System  

NASA Astrophysics Data System (ADS)

On Boxing Day 2004, a severe tsunami was generated by a strong earthquake in Northern Sumatra causing a large number of casualties. At this time, neither an offshore buoy network was in place to measure tsunami waves, nor a system to disseminate tsunami warnings to local governmental entities. Since then, buoys have been developed by Indonesia and Germany, complemented by NOAA's Deep-ocean Assessment and Reporting of Tsunamis (DART) buoys, and have been moored offshore Sumatra and Java. The suite of sensors for offshore tsunami detection in Indonesia has been advanced by adding GPS technology for water level measurements. The usage of GPS buoys in tsunami warning systems is a relatively new approach. The concept of the German Indonesian Tsunami Early Warning System (GITEWS) (Rudloff et al., 2009) combines GPS technology and ocean bottom pressure (OBP) measurements. Especially for near-field installations where the seismic noise may deteriorate the OBP data, GPS-derived sea level heights provide additional information. The GPS buoy technology is precise enough to detect medium to large tsunamis of amplitudes larger than 10 cm. The analysis presented here suggests that for about 68% of the time, tsunamis larger than 5 cm may be detectable.

Schöne, T.; Pandoe, W.; Mudita, I.; Roemer, S.; Illigner, J.; Zech, C.; Galas, R.

2011-03-01

347

Investigation of GPS/IMU Positioning System for Mining Equipment  

SciTech Connect

The objective of this project is to investigate the applicability of a combined Global Positioning System and Inertial Measurement Unit (GPS/IMU) for information based displays on earthmoving machines and for automated earthmoving machines in the future. This technology has the potential of allowing an information-based product like Caterpillar's Computer Aided Earthmoving System (CAES) to operate in areas with satellite shading. Satellite shading is an issue in open pit mining because machines are routinely required to operate close to high walls, which reduces significantly the amount of the visible sky to the GPS antenna mounted on the machine. An inertial measurement unit is a product, which provides data for the calculation of position based on sensing accelerations and rotation rates of the machine's rigid body. When this information is coupled with GPS it results in a positioning system that can maintain positioning capability during time periods of shading.

Ken L. Stratton

2006-09-13

348

Low-Cost INS/GPS Integration: Concepts and Testing  

E-print Network

of inertial units is the main obstacle for their inclusion in precision navigation systems to support a variety of application areas. Standard inertial navigation systems (INS) use precise gyro inclusion of these sensors to augment GPS in precision navigation systems. Standard inertial navigation

Calgary, University of

349

Inertial navigation systems for mobile robots  

Microsoft Academic Search

A low-cost solid-state inertial navigation system (INS) for mobile robotics applications is described. Error models for the inertial sensors are generated and included in an extended Kalman filter (EKF) for estimating the position and orientation of a moving robot vehicle. Two different solid-state gyroscopes have been evaluated for estimating the orientation of the robot. Performance of the gyroscopes with error

Billur Barshan; Hugh F. Durrant-Whyte

1995-01-01

350

New mechanization equations for aided inertial navigation systems  

NASA Technical Reports Server (NTRS)

Inertial navigation equations are developed which use area navigation (RNAV) waypoints and runway references as coodinate centers. The formulation is designed for aided inertial navigation systems and gives a high numerical accuracy through all phases of flight. A new formulation of the error equations for inertial navigation systems is also presented. This new formulation reduces numerical calculations in the use of Kalman filters for aided inertial navigation systems.

Schmidt, S. F.; Bjorkman, W. S.; Conrad, B.

1973-01-01

351

Design study of a low cost civil aviation GPS receiver system  

NASA Technical Reports Server (NTRS)

A low cost Navstar receiver system for civil aviation applications was defined. User objectives and constraints were established. Alternative navigation processing design trades were evaluated. Receiver hardware was synthesized by comparing technology projections with various candidate system designs. A control display unit design was recommended as the result of field test experience with Phase I GPS sets and a review of special human factors for general aviation users. Areas requiring technology development to ensure a low cost Navstar Set in the 1985 timeframe were identified.

Cnossen, R.; Gilbert, G. A.

1979-01-01

352

GPS Bibliography by the National Geodetic Survey  

NSDL National Science Digital Library

This bibliography, intended for more advanced users, is a compilation of peer-reviewed articles published in 2006 describing original research with citations on Global Positioning Systems (GPS) and Global Satellite Navigation Systems (GNSS).

2010-11-24

353

International GPS (Global Positioning System) Service for Geodynamics  

NASA Technical Reports Server (NTRS)

The International GPS (Global Positioning System) Service for Geodynamics (IGS) began formal operation on January 1, 1994. This first annual report is divided into sections, which mirror different aspects of the service. Section (1) contains general information, including the history of the IGS, its organization, and the global network of GPS tracking sites; (2) contains information on the Central Bureau Information System; (3) describes the International Earth Rotation Service (IERS); (4) details collecting and distributing IGS data in Data Center reports; (6) describes how the IGS Analysis Centers generate their products; (7) contains miscellaneous contributions from other organizations that share common interests with the IGS.

Zumberge, J. F. (Editor); Liu, R. (Editor); Neilan, R. E. (Editor)

1995-01-01

354

Inertial navigation system for directional surveying  

SciTech Connect

A Wellbore Inertial Navigation System (WINS) was developed and tested. Developed for directional surveying of geothermal, oil, and gas wells, the system uses gyros and accelerometers to obtain survey errors of less than 10 ft (approx. 3 m) in a 10,000-ft (approx. 300-m) well. The tool, which communicates with a computer at the surface, is 4 in. (approx. 10 cm) in diameter and 20 ft (approx. 6.1 m) long. The concept and hardware is based on a system developed by Sandia for flight vehicles.

Kohler, S.M.

1982-09-01

355

Fiber optic gyroscopes for vehicle navigation systems  

NASA Astrophysics Data System (ADS)

Fiber optic gyroscopes (FOGs) have been developed for vehicle navigation systems and are used in Toyota Motor Corporation models Mark II, Chaser and Cresta in Japan. Use of FOGs in these systems requires high reliability under a wide range of conditions, especially in a temperature range between -40 and 85 degree(s)C. In addition, a high cost-performance ratio is needed. We have developed optical and electrical systems that are inexpensive and can perform well. They are ready to be mass-produced. FOGs have already been installed in luxury automobiles, and will soon be included in more basic vehicles. We have developed more inexpensive FOGs for this purpose.

Kumagai, Tatsuya; Soekawa, Hirokazu; Yuhara, Toshiya; Kajioka, Hiroshi; Oho, Shigeru; Sonobe, Hisao

1994-03-01

356

Space shuttle navigation analysis  

NASA Technical Reports Server (NTRS)

A detailed analysis of space shuttle navigation for each of the major mission phases is presented. A covariance analysis program for prelaunch IMU calibration and alignment for the orbital flight tests (OFT) is described, and a partial error budget is presented. The ascent, orbital operations and deorbit maneuver study considered GPS-aided inertial navigation in the Phase III GPS (1984+) time frame. The entry and landing study evaluated navigation performance for the OFT baseline system. Detailed error budgets and sensitivity analyses are provided for both the ascent and entry studies.

Jones, H. L.; Luders, G.; Matchett, G. A.; Sciabarrasi, J. E.

1976-01-01

357

The QuakeSim System for GPS Time Series Analysis  

Microsoft Academic Search

We present a system for analysis of GPS time series data available to geosciences users through a web services \\/ web portal interface. The system provides two time series analysis methods, one based on hidden Markov model (HMM) segmentation, the other based on covariance descriptor analysis (CDA). In addition, it provides data pre-processing routines that perform spike noise removal, linear

R. A. Granat; X. Gao; M. Pierce; J. Wang

2010-01-01

358

An Interdisciplinary Approach at Studying the Earth-Sun System with GPS/GNSS and GPS-like Signals  

NASA Technical Reports Server (NTRS)

The value of Global Positioning Satellites (GPS) measurements to atmospheric science, space physics, and ocean science, is now emerging or showing a potential to play a major role in the evolving programs of NASA, NSF and NOAA. The objective of this communication is to identify and articulate the key scientific questions that are optimally, or perhaps uniquely, addressed by GPS or GPS-like observations, and discuss their relevance to existing or planned national Earth-science research programs. The GPS-based ocean reflection experiments performed to date have demonstrated the precision and spatial resolution suitable to altimetric applications that require higher spatial resolution and more frequent repeat than the current radar altimeter satellites. GPS radio occultation is promising as a climate monitoring tool because of its benchmark properties: its raw observable is based on extremely accurate timing measurements. GPS-derived temperature profiles can provide meaningful climate trend information over decadal time scales without the need for overlapping missions or mission-to-mission calibrations. By acquiring data as GPS satellites occult behind the Earth's limb, GPS also provides high vertical resolution information on the vertical structure of electron density with global coverage. New experimental techniques will create more comprehensive TEC maps by using signals reflected from the oceans and received in orbit. This communication will discuss a potential future GNSS Earth Observing System project which would deploy a constellation of satellites using GPS and GPS-like measurements, to obtain a) topography measurements based on GPS reflections with an accuracy and horizontal resolution suitable for eddy monitoring, and h) climate-records quality atmospheric temperature profiles. The constellation would also provide for measurements of ionospheric elec tron density. This is a good example of an interdisciplinary mission concept, with broad science objectives of high societal relevance, al l resting on common cost-effective technology.

Zuffada, Cinzia; Hajj, George; Mannucci, Anthony J.; Chao, Yi; Ao, Chi; Zumberge, James

2005-01-01

359

75 FR 68701 - Establishment and Amendment of Area Navigation (RNAV) Routes; Alaska  

Federal Register 2010, 2011, 2012, 2013

...Amendment of Area Navigation (RNAV) Routes...modifies four Area Navigation (RNAV) routes in...RNAV, for use by aircraft having instrument...Global Positioning System (GPS)/Global Navigation Satellite...

2010-11-09

360

75 FR 32120 - Proposed Establishment and Amendment of Area Navigation (RNAV) Routes; Alaska  

Federal Register 2010, 2011, 2012, 2013

...Amendment of Area Navigation (RNAV) Routes...and modify four Area Navigation (RNAV) routes in...RNAV, for use by aircraft having instrument...Global Positioning System (GPS)/ Global Navigation Satellite...

2010-06-07

361

Aircraft Navigation: Design Theory for A Self-Organizing, High Accuracy Navigation System  

Microsoft Academic Search

Aircraft navigation system accuracy can be optimized by proper integration of present subsystems. The Loran-C coordinate converter is a new tool which facilitates the system integration task. Certain navigation devices, e.g., a doppler-free-gyro subsystem, are calibrated in-flight to yield a much better total navigation system. Self-organizing features are included to perform simple decision-making functions automatically and thus, release the human

V. J. Burns

1963-01-01

362

A relativistic and autonomous navigation satellite system  

E-print Network

A relativistic positioning system has been proposed by Bartolom\\'e Coll in 2002. Since then, several group developed this topic with different approaches. I will present a work done in collaboration with Ljubljana University and the ESA Advanced Concepts Team. We developed a concept, Autonomous Basis of Coordinates, in order to take advantage of the full autonomy of a satellite constellation for navigation and positioning, by means of satellite inter-links. I will present the advantages of this new paradigm and a number of potential application for reference systems, geophysics and relativistic gravitation.

Pacôme Delva; Andrej Cadez; Uros Kostic; Sante Carloni

2011-06-16

363

Pre-Flight Testing of Spaceborne GPS Receivers using a GPS Constellation Simulator  

NASA Technical Reports Server (NTRS)

The NASA Goddard Space Flight Center (GSFC) Global Positioning System (GPS) applications test facility has been established within the GSFC Guidance Navigation and Control Center. The GPS test facility is currently housing the Global Simulation Systems Inc. (GSSI) STR2760 GPS satellite 40-channel attitude simulator and a STR4760 12-channel navigation simulator. The facility also contains a few other resources such as an atomic time standard test bed, a rooftop antenna platform and a radome. It provides a new capability for high dynamics GPS simulations of space flight that is unique within the aerospace community. The GPS facility provides a critical element for the development and testing of GPS based technologies i.e. position, attitude and precise time determination used on-board a spacecraft, suborbital rocket balloon. The GPS simulation system is configured in a transportable rack and is available for GPS component development as well as for component, spacecraft subsystem and system level testing at spacecraft integration and tests sites. The GPS facility has been operational since early 1996 and has utilized by space flight projects carrying GPS experiments, such as the OrbView-2 and the Argentine SAC-A spacecrafts. The SAC-A pre-flight test data obtained by using the STR2760 simulator and the comparison with preliminary analysis of the GPS data from SAC-A telemetry are summarized. This paper describes pre-flight tests and simulations used to support a unique spaceborne GPS experiment. The GPS experiment mission objectives and the test program are described, as well as the GPS test facility configuration needed to verify experiment feasibility. Some operational and critical issues inherent in GPS receiver pre-flight tests and simulations using this GPS simulation, and test methodology are described. Simulation and flight data are presented. A complete program of pre-flight testing of spaceborne GPS receivers using a GPS constellation simulator is detailed.

Kizhner, Semion; Davis, Edward; Alonso, R.

1999-01-01

364

Pre-Flight Testing of Spaceborne GPS Receivers Using a GPS Constellation Simulator  

NASA Technical Reports Server (NTRS)

The NASA Goddard Space Flight Center (GSFC) Global Positioning System (GPS) applications test facility has been established within the GSFC Guidance Navigation and Control Center. The GPS test facility is currently housing the Global Simulation Systems Inc. (GSSI) STR2760 GPS satellite 40-channel attitude simulator and a STR4760 12-channel navigation simulator. The facility also contains a few other resources such as an atomic time standard test bed, a rooftop antenna platform and a radome. It provides a new capability for high dynamics GPS simulations of space flight that is unique within the aerospace community. The GPS facility provides a critical element for the development and testing of GPS based technologies i.e. position, attitude and precise time determination used on-board a spacecraft, suborbital rocket or balloon. The GPS simulator system is configured in a transportable rack and is available for GPS component development as well as for component, spacecraft subsystem and system level testing at spacecraft integration and test sites. The GPS facility has been operational since early 1996 and has been utilized by space flight projects carrying GPS experiments, such as the OrbView-2 and the Argentine SAC-A spacecrafts. The SAC-A pre-flight test data obtained by using the STR2760 simulator and the comparison with preliminary analysis of the GPS data from SAC-A telemetry are summarized. This paper describes pre-flight tests and simulations used to support a unique spaceborne GPS experiment. The GPS experiment mission objectives and the test program are described, as well as the GPS test facility configuration needed to verify experiment feasibility. Some operational and critical issues inherent in GPS receiver pre-flight tests and simulations using this GPS simulator, and test methodology are described. Simulation and flight data are presented. A complete program of pre-flight testing of spaceborne GPS receivers using a GPS constellation simulator is detailed.

Kizhner, Semion; Davis, Edward; Alonso, Roberto

1999-01-01

365

Satellite emission radio interferometric earth surveying series - GPS geodetic system  

NASA Technical Reports Server (NTRS)

A concept called SERIES (satellite emissions radio interferometric earth surveying) which makes use of GPS (global positioning system) radio transmissions without any satellite modifications, is described. Through the use of very long baseline interferometry (VLBI) and its calibration methods, 0.5 to 3 cm three dimensional baseline accuracy can be achieved over distances of 2 to 200 km respectively, with only 2 hours of on-site data acquisition. Attention is given to such areas as: the radio flux equivalent of GPS transmissions, synthesized delay precision, transmission and frequency subsystem requirements, tropospheric and ionospheric errors. Applications covered include geodesy and seismic tectonics.

Macdoran, P. F.

1979-01-01

366

Site Selection Plan and Installation Guidelines for a Nationwide Differential GPS Service.  

National Technical Information Service (NTIS)

The Global Positioning System (GPS), in its current form, is used within the transportation industry for vehicle tracking and navigation. With the advent of a nationwide differential GPS (DGPS) service, this role will expand to include public safety, infr...

R. L. Ketchum, J. J. Lemmon, J. R. Hoffman

1997-01-01

367

GPS-Like Phasing Control of the Space Solar Power System Transmission Array  

NASA Technical Reports Server (NTRS)

The problem of phasing of the Space Solar Power System's transmission array has been addressed by developing a GPS-like radio navigation system. The goal of this system is to provide power transmission phasing control for each node of the array that causes the power signals to add constructively at the ground reception station. The phasing control system operates in a distributed manner, which makes it practical to implement. A leader node and two radio navigation beacons are used to control the power transmission phasing of multiple follower nodes. The necessary one-way communications to the follower nodes are implemented using the RF beacon signals. The phasing control system uses differential carrier phase relative navigation/timing techniques. A special feature of the system is an integer ambiguity resolution procedure that periodically resolves carrier phase cycle count ambiguities via encoding of pseudo-random number codes on the power transmission signals. The system is capable of achieving phasing accuracies on the order of 3 mm down to 0.4 mm depending on whether the radio navigation beacons operate in the L or C bands.

Psiaki, Mark L.

2003-01-01

368

Performance Analysis and Architectures for INS-Aided GPS Tracking Loops  

E-print Network

characteristics, which have been exploited in the design of integrated GPS-inertial navigation and guidance from GPS and an Inertial Navigation System using either loose integration (i.e., integration are in the areas of navigation, guidance and control with an emphasis on sensor fusion and system integration

Stanford University

369

A GPS Real Time Earthquake and Tsunami (GREAT) Alert System  

NASA Astrophysics Data System (ADS)

The GREAT Alert is a NASA-sponsored, real-time prototype system designed to enhance natural hazard warning capability and damage assessment. The system takes advantage of the increasingly available global and regional real-time GPS data, as well as advanced fault and ocean dynamics models to enable more accurate and timely assessment of the magnitude and mechanism of large earthquakes, and the magnitude and direction of resulting tsunamis. We will describe the prototype operational system being developed, highlighting the underlying GNSS technology. The key system components are: 1. The operational real-time estimation of site coordinates from hundreds of GPS sites using a precise point positioning (PPP) algorithm. This is accomplished by the NASA Global Differential GPS (GDGPS) System which, unlike other GPS algorithms such as real-time kinematic (RTK), is insensitive to motions of any ground-based reference stations in the vicinity of an event. 2. The application of data filtering and quality control techniques to the real-time site position time series in order to enhance the accurate retrieval of co-seismic site motions. 3. Usage of a Fingerprint inversion model (and potentially other models) for the rapid determination of the earthquake displacement field from the GPS-based records of ground motion at each station. 4. Detected and modeled seafloor displacements are then used within a special ocean dynamics model to determine tsunami source energy and scales, and estimate the tsunami propagation. 5. The resulting near-real-time information about earthquake source properties magnitude, type, and when relevant, magnitude and direction of the resulting tsunami, is then available to the responsible agencies to help in their decision-making processes. We will discuss the preliminary performance of the system, and analyze the aspects of GNSS infrastructure and technology that require further investments in order to realize the full potential of the GREAT Alert system and similar approaches for natural hazard monitoring.

Bar-Sever, Yoaz

2010-05-01

370

An Inexpensive and Robust GPS/INS Attitude System for Automobiles  

E-print Network

An Inexpensive and Robust GPS/INS Attitude System for Automobiles Santiago Alban, Stanford-cost and robust GPS/INS attitude system for automobiles, and deep integration of INS systems with GPS tracking loops. ABSTRACT Many of the sophisticated control systems of modern automobiles require measurements

Stanford University

371

The Global Positioning System  

NSDL National Science Digital Library

This site presents information about the Global Positioning System (GPS), including basic information, images, and plentiful in-depth technical information about GPS. Topics covered include U.S. Department of Defense Satellite Navigation System, GPS Positioning Services Specified in the Federal Radionavigation Plan, GPS Satellite Signals, GPS Data, Position and Time from GPS, GPS Error Sources, Geometric Dilution of Precision, and Differential GPS Techniques. There is a list of related documents and a reference list.

Foote, Kenneth; Dana, Peter

372

Kinematic GPS positioning in a highway environment  

E-print Network

The global positioning system (GPS) is a satellite based navigation system which can give twenty-four hour three-dimensional worldwide coverage. The Differential GPS uses the NAVSTAR satellites and a beacon at a known site to reduce the error...

Li, Yingfeng

2012-06-07

373

Simulation of Guidance, Navigation, and Control Systems for Formation Flying Missions  

NASA Technical Reports Server (NTRS)

Concepts for missions of distributed spacecraft flying in formation abound. From high resolution interferometry to spatially distributed in-situ measurements, these mission concepts levy a myriad of guidance, navigation, and control (GNC) requirements on the spacecraft/formation as a single system. A critical step toward assessing and meeting these challenges lies in realistically simulating distributed spacecraft systems. The Formation Flying TestBed (FFTB) at NASA Goddard Space Flight Center's (GSFC) Guidance, Navigation, and Control Center is a hardware-in-the-loop simulation and development facility focused on GNC issues relevant to formation flying systems. The FFTB provides a realistic simulation of the vehicle dynamics and control for formation flying missions in order to: (1) conduct feasibility analyses of mission requirements, (2) conduct and answer mission and spacecraft design trades, and (3) serve as a host for GNC software and hardware development and testing. The initial capabilities of the FFTB are based upon an integration of high fidelity hardware and software simulation, emulation, and test platforms developed or employed at GSFC in recent years, including a high-fidelity Global Positioning System (GPS) simulator which has been a fundamental component of the GNC Center's GPS Test Facility. The FFTB will be continuously evolving over the next several years from a tool with capabilities in GPS navigation hardware/software-in-the-loop analysis and closed loop GPS-based orbit control algorithm assessment. Eventually, it will include full capability to support all aspects of multi-sensor, absolute and relative state determination and control, in all (attitude and orbit) degrees of freedom, as well as information management for satellite clusters and constellations. A detailed description of the FFTB architecture is presented in the paper.

Burns, Rich; Bauer, Frank H. (Technical Monitor)

2002-01-01

374

Autonomous underwater pipeline monitoring navigation system  

NASA Astrophysics Data System (ADS)

This paper details the development of an autonomous motion-control and navigation algorithm for an underwater autonomous vehicle, the Ocean Server IVER3, to track long linear features such as underwater pipelines. As part of this work, the Nonlinear and Autonomous Systems Laboratory (NAS Lab) developed an algorithm that utilizes inputs from the vehicles state of the art sensor package, which includes digital imaging, digital 3-D Sidescan Sonar, and Acoustic Doppler Current Profilers. The resulting algorithms should tolerate real-world waterway with episodic strong currents, low visibility, high sediment content, and a variety of small and large vessel traffic.

Mitchell, Byrel; Mahmoudian, Nina; Meadows, Guy

2014-06-01

375

Effects of Geodetic Uncertainties on a Damped Inertial Navigation System  

Microsoft Academic Search

Gravity uncertainties are an inexorable source of error in all inertial navigation systems and are particularly important in high-quality inertial navigation systems. In this paper the steady-state rms errors that are excited in a damped inertial navigation system are analytically determined for four gravity uncertainty models and two vehicle maneuver models. The statistical approach used in this paper is compared

Stanley Jordan

1973-01-01

376

Factor Graph Based Incremental Smoothing in Inertial Navigation Systems  

E-print Network

Factor Graph Based Incremental Smoothing in Inertial Navigation Systems Vadim Indelman, Stephen Abstract--This paper describes a new approach for informa- tion fusion in inertial navigation systems. INTRODUCTION Information fusion in inertial navigation systems is essential for any practical application

Kaess, Michael

377

Temporal and spatial precursors in the ionospheric global positioning system (GPS) total electron content observed  

E-print Network

Temporal and spatial precursors in the ionospheric global positioning system (GPS) total electron maps of the TEC derived from worldwide groundbased receivers of the global positioning system (GPS in the ionospheric global positioning system (GPS) total electron content observed before the 26 December 2004 M9

Chen, Yuh-Ing

378

Updated receiver survey system uses an infrared camera, GPS technology, and computer software to rapidly  

E-print Network

Updated receiver survey system uses an infrared camera, GPS technology, and computer software for performance issues using an infrared (IR) camera, global positioning system (GPS) technology, and computer Achievement NREL has created a receiver survey system that integrates an IR camera, GPS technology

379

Trajectory determination and analysis in sports by satellite and inertial navigation.  

E-print Network

??This research presents methods for performance analysis in sports through the integration of Global Positioning System (GPS) measurements with Inertial Navigation System (INS). The described… (more)

Wägli, Adrian

2009-01-01

380

ORIGINAL ARTICLE Satellite clock bias estimation for iGPS  

E-print Network

Ã? Springer-Verlag 2012 Abstract The High Integrity GPS program seeks to provide enhanced navigation to be accurate to within 200 ns while always meeting the initial system specification of half a microsecond to improve the position, navigation, and timing performance for military GPS users by integrating

Larson, Kristine

381

GPS Tutorial by Trimble  

NSDL National Science Digital Library

This animated tutorial introduces users to Global Positioning Systems (GPS) technology. Topics include what GPS is, how it works, timing, satellite error, differential GPS, and how to use GPS. There is also a glossary.

2010-08-12

382

GPS Timing and Control System of the HAWC Detector  

E-print Network

The design and performance of the GPS Timing and Control (GTC) System of the High Altitude Water Cerenkov (HAWC) gamma ray observatory is described. The GTC system provides a GPS synchronized absolute timestamp, with an accuracy better than 1$\\mu$s, for each recorded event in HAWC. In order to avoid any slack between the recorded data and the timestamp, timestamps are injected to the main data acquisition (DAQ) system after the Front-end Electronic Boards (FEBs). When HAWC is completed, the HAWC main DAQ will use 10 time to digital converters (TDCs). In order to keep all the TDCs in sync, the GTC system provides a synchronized clock signal, coordinated trigger signal, and control signals to all TDCs.

Abeysekara, Anushka Udara; Edmunds, Dan; Linnemanna, James; Imranc, Asif; Kunded, Gerd; Wisher, Ian

2014-01-01

383

A GPS measurement system for precise satellite tracking and geodesy  

NASA Technical Reports Server (NTRS)

NASA is pursuing two key applications of differential positioning with the Global Positioning System (GPS): sub-decimeter tracking of earth satellites and few-centimeter determination of ground-fixed baselines. Key requirements of the two applications include the use of dual-frequency carrier phase data, multiple ground receivers to serve as reference points, simultaneous solution for use position and GPS orbits, and calibration of atmospheric delays using water vapor radiometers. Sub-decimeter tracking will be first demonstrated on the TOPEX oceanographic satellite to be launched in 1991. A GPS flight receiver together with at least six ground receivers will acquire delta range data from the GPS carriers for non-real-time analysis. Altitude accuracies of 5 to 10 cm are expected. For baseline measurements, efforts will be made to obtain precise differential pseudorange by resolving the cycle ambiguity in differential carrier phase. This could lead to accuracies of 2 or 3 cm over a few thousand kilometers. To achieve this, a high-performance receiver is being developed, along with improved calibration and data processing techniques. Demonstrations may begin in 1986.

Yunck, T. P.; Wu, S.-C.; Lichten, S. M.

1985-01-01

384

Synthesis of a Very Accurate Inertial Navigation System  

Microsoft Academic Search

A philosophy for the synthesis of a very accurate inertial navigation system is developed here. First, the requirements for a spherical earth navigator are determined, and the basis for a navigator error analysis is developed through the use of mathematical error models. Four types of redundant information are then considered in sequence: external speed information, redundant system gyro, external discrete

Arthur Gelb

1965-01-01

385

Automatic alignment and calibration of an inertial navigation system  

Microsoft Academic Search

In this paper we derive a simple six degree of freedom navigator, Earth-surface navigator, for terranean vehicle application, using low grade gyros. The calibration and alignment of the navigator are investigated when the system is at rest. Based on the observability of the error model when the system is at rest, a state transformation is presented. This transformation decouples the

Samer S. Saab; Kristjan T. Gunnarsson

1994-01-01

386

Optimum Control Using Signal Processing in Integrated Aerospace navigation systems  

Microsoft Academic Search

The global - air - navigation telecommunication network is an integrated system which joins telecommunication, navigation, and observation. This integrated system provides communication in real-time scale between any two inverse points .Direct and indirect measurement ( DIM ) of basic navigational parameters of aircraft movement ( position , velocity , acceleration ,….. etc ) should be done accurately and precision

AYMAN AL-LAWAMA; ABDEL-RAHMAN AL-QAWASMI; OMAR AL-AYASRAH

387

DESIGN AND PERFORMANCE OF A ROBUST GPS/INS ATTITUDE SYSTEM FOR AUTOMOBILE  

E-print Network

DESIGN AND PERFORMANCE OF A ROBUST GPS/INS ATTITUDE SYSTEM FOR AUTOMOBILE APPLICATIONS cars has led to a growing number of GPS applications in the automobile industry. In addition of an inexpensive and ro- bust attitude system based on GPS and inertial sensors, suitable for use in automobiles

Stanford University

388

GPS Time Synchronization System for K2K 1 H. G. Berns and R. J. Wilkes  

E-print Network

GPS Time Synchronization System for K2K 1 H. G. Berns and R. J. Wilkes Department of Physics System (GPS) provides a means for satisfying this requirement at very low cost. In addition to low­resolution time data (day of year, hour, minute, second), commercial GPS receivers output a 1 pulse per sec (1PPS

Berns, Hans-Gerd

389

GPS Time Synchronization System for K2K1 H. G. Berns and R. J. Wilkes  

E-print Network

GPS Time Synchronization System for K2K1 H. G. Berns and R. J. Wilkes Department of Physics System (GPS) provides a means for satisfying this requirement at very low cost. In addition to low- resolution time data (day of year, hour, minute, second), commercial GPS receivers output a 1 pulse per sec

Berns, Hans-Gerd

390

Reliable GPS-Based Timing for Power Systems: A Multi-Layered Multi-Receiver Architecture  

E-print Network

Reliable GPS-Based Timing for Power Systems: A Multi-Layered Multi-Receiver Architecture Liang Heng, and protection functions. PMUs use the Global Positioning System (GPS) to synchronize measurements across a wide geographical area. Unfortunately, low-received-power, unencrypted civil GPS signals are vulnerable to jamming

Gao, Grace Xingxin

391

Global Positioning System (GPS) Time Dissemination for Real-Time Applications  

Microsoft Academic Search

This paper presents an overview of the Global Positioning System (GPS) for the potential precise time and time interval user with special reference to real -time systems. An overview of GPS operation is presented and GPS error sources are described as they relate to the timing user. A review of receiver types and receiver tasks provides the basis for understanding

Peter H. Dana

1997-01-01

392

US Coast Guard differential GPS network  

SciTech Connect

In order to aid navigation and to prevent disasters such as oil spills, collisions, and wrecks of vessels and aircraft, the US Coast Guard is charged with establishing, maintaining, and operating electronic aids to navigation. In a technological advance developed and operated by the Department of Defense, the global positioning system (GPS) provides all-weather global coverage, 24 hours/day at unprecedented accuracies. GPS provides standard positioning service (SPS) and precise positioning service (PPS). By applying differential techniques to GPS, navigational accuracies of better than 10 meters can be achieved. For the first time, an all-weather system is possible to meet all the marine navigator's needs including harbor and harbor approach navigation. This should revolutionize navigation safety and efficiency, surveying operations, search and rescue operations, and underwater mine disposal efficiency and safety.

Alsip, D.H.; Butler, J.M.; Radice, J.T.

1993-03-01

393

Presented at ION GPS-01, Salt Lake City, September 11-14, 2001 1 P3 Aircraft Buffeting Measurement  

E-print Network

, and has worked extensively on the integration of GPS and inertial navigation systems for precise aircraftPresented at ION GPS-01, Salt Lake City, September 11-14, 2001 1 P3 Aircraft Buffeting Measurement and navigation. He has been involved with GPS development and applications since 1980. Mr. Michael Olynik is a M

Calgary, University of

394

Constrained navigation algorithms for strapdown inertial navigation systems with reduced set of sensors  

Microsoft Academic Search

This paper develops a family of algorithms for low-cost strapdown inertial navigation system for land vehicles. Constraints on the motion of land vehicles are defined. They include constraints on vehicle's orientation relative to the Earth surface, and relationship between vehicle's attitude and its velocity direction. Navigation equations are derived that assume validity of these constraints on the vehicle's motion. Compared

Aleksandr Brandt; John F. Gardner

1998-01-01

395

Navigation system for autonomous mapper robots  

NASA Astrophysics Data System (ADS)

This paper describes the conception and realization of a fast, robust, and general navigation system for a mobile (wheeled or legged) robot. A database, representing a high level map of the environment is generated and continuously updated. The first part describes the legged target vehicle and the hexapod robot being developed. The second section deals with spatial and temporal sensor fusion for dynamic environment modeling within an obstacle/free space probabilistic classification grid. Ultrasonic sensors are used, others are suspected to be integrated, and a-priori knowledge is treated. US sensors are controlled by the path planning module. The third part concerns path planning and a simulation of a wheeled robot is also presented.

Halbach, Marc; Baudoin, Yvan

1993-05-01

396

First results from an airborne GPS radio occultation system for atmospheric profiling  

NASA Astrophysics Data System (ADS)

Positioning System (GPS) radio occultation (RO) from low Earth-orbiting satellites has increased the quantity of high-vertical resolution atmospheric profiles, especially over oceans, and has significantly improved global weather forecasting. A new system, the Global Navigation Satellite Systems Instrument System for Multistatic and Occultation Sensing (GISMOS), has been developed for RO sounding from aircraft. GISMOS also provides high-vertical resolution profiles that are insensitive to clouds and precipitation, and in addition, provides greater control on the sampling location, useful for targeted regional studies. The feasibility of the system is demonstrated with a flight carried out during development of an Atlantic tropical storm. The data have been evaluated through a comparison with dropsonde data. The new airborne RO system will effectively increase by more than 50% the number of profiles available for studying the evolution of tropical storms during this campaign and could potentially be deployed on commercial aircraft in the future.

Haase, J. S.; Murphy, B. J.; Muradyan, P.; Nievinski, F. G.; Larson, K. M.; Garrison, J. L.; Wang, K.-N.

2014-03-01

397

Two systems of spatial representation underlying navigation  

Microsoft Academic Search

We review evidence for two distinct cognitive processes by which humans and animals represent the navigable environment. One\\u000a process uses the shape of the extended 3D surface layout to specify the navigator’s position and orientation. A second process\\u000a uses objects and patterns as beacons to specify the locations of significant objects. Although much of the evidence for these\\u000a processes comes

Sang Ah Lee; Elizabeth S. Spelke

2010-01-01

398

GPS time transfer smooth using discrete wavelet  

Microsoft Academic Search

Time service is the precondition of precise navigation in radio navigation system, the cesium atomic clock of high stability is used in this system as frequency reference and GPS time receiver is used. To solve the problem of system synchronize error caused by satellite movement, Doppler frequency shift, ionosphere refraction, etc. sliding window method and discrete wavelet method are introduced

Ping Huang; Bing-fa Zu

2009-01-01

399

Development of an Off-board Car Navigation System  

NASA Astrophysics Data System (ADS)

This paper describes our off-board car navigation system. Our off-board car navigation system has (1) a center to provide navigation functions using the latest maps and POI (Point Of Interests) through the internet; and (2) a more compactly sized client terminal compared to conventional on-board systems. We evaluated the system. The concept of the system was evaluated as acceptable, but some problems that need solutions were identified.

Machii, Kimiyoshi; Endo, Yoshinori; Matsuo, Shigeru; Tanaka, Katsuaki; Morioka, Michio; Nakamura, Kozo; Yamaashi, Kimiya; Nakamura, Toru

400

GPS receiver prototype for integration into system-on-chip  

Microsoft Academic Search

The paper describes the design of a GPS receiver architected for integration into system-on-chip solutions. The application and the design challenges are first presented followed by the proposed solution. The solution is a complete environment starting from algorithmic and architectural development including modeling down-to implementation and verification by simulation on a software as well as a hardware platform. The resulting

A. Rabaeijs; D. Grosso; X. Huang; D. Qi

2003-01-01

401

A GPS-Based On-Demand Shuttle Bus System  

Microsoft Academic Search

We propose the implementation of an on-demand system to serve requests to ride shuttles on a university campus. Assuming that each client and each shuttle bus has a GPS device, we devise two online algorithms: the k-means based algorithm, and the general pool-based algorithm. The former has two components: the first deals with the problem of assigning requests to shuttles,

Maria Vanina; Martinez Gerardo; I. Simari; Carlos D. Castillo; Nir J. Peer

402

International Global Navigation Satellite Systems Society IGNSS Symposium 2011  

E-print Network

the performance advantages of the method proposed. KEYWORDS: Pedestrian Navigation, Integration, Fusion, Inertial1 International Global Navigation Satellite Systems Society IGNSS Symposium 2011 University of New Navigation in Signal Degraded Environments Jared B. Bancroft University of Calgary, AB, Canada 0011 1 403 210

Calgary, University of

403

Multiband Pyramidal Antenna for Radio Navigation and Telemetry Systems  

E-print Network

Multiband Pyramidal Antenna for Radio Navigation and Telemetry Systems Sami Hebib*(1,2) , Hervé combining radio navigation and MicroSAT telemetry applications was recently introduced by the authors with independent and easily adjustable operating frequency ratios that combines radio navigation and telemetry

Boyer, Edmond

404

Robotics and Autonomous Systems 30 (2000) 133153 Biomimetic robot navigation  

E-print Network

Robotics and Autonomous Systems 30 (2000) 133­153 Biomimetic robot navigation Matthias O. Franz Abstract In the past decade, a large number of robots has been built that explicitly implement biological applications, most notably in the field of indoor robot navigation. While simpler insect navigation behaviours

405

Integrated vision\\/inertial navigation system design using nonlinear filtering  

Microsoft Academic Search

Addresses the problem of navigation system design for autonomous aircraft landing. New nonlinear filter structures are introduced to estimate the position of an aircraft with respect to a possibly moving landing site, such as a naval vessel, based on measurements provided by airborne vision and inertial sensors. By exploring the geometry of the navigation problem, the navigation filter dynamics are

I. Kaminer; A. Pascoal; Wei Kang

1999-01-01

406

Airborne Digital Sensor System and GPS-aided inertial technology for direct geopositioning in rough terrain  

USGS Publications Warehouse

High-resolution airborne digital cameras with onboard data collection based on the Global Positioning System (GPS) and inertial navigation systems (INS) technology may offer a real-time means to gather accurate topographic map information by reducing ground control and eliminating aerial triangulation. Past evaluations of this integrated system over relatively flat terrain have proven successful. The author uses Emerge Digital Sensor System (DSS) combined with Applanix Corporation?s Position and Orientation Solutions for Direct Georeferencing to examine the positional mapping accuracy in rough terrain. The positional accuracy documented in this study did not meet large-scale mapping requirements owing to an apparent system mechanical failure. Nonetheless, the findings yield important information on a new approach for mapping in Antarctica and other remote or inaccessible areas of the world.

Sanchez, Richard D.

2004-01-01

407

What is GPS? Global radionavigation system, to provide locations in rea  

E-print Network

What is GPS? · Global radionavigation system, to provide locations in rea military, with few-meter accuracy. · Conceived in the 1970's, first satellites launched 19 ``operational'' in 1994. #12;What is GPS in the 1970's, first satellites launched 19 ``operational'' in 1994. · Meanwhile..... #12;What is GPS

Fialko, Yuri

408

GPS Meteorology: Remote Sensing of Atmospheric Water Vapor Using the Global Positioning System  

Microsoft Academic Search

We present a new approach to remote sensing of water vapor based on the global positioning system (GPS). Geodesists and geophysicists have devised methods for estimating the extent to which signals propagating from GPS satellites to ground-based GPS receivers are delayed by atmospheric water vapor. This delay is parameterized in terms of a time-varying zenith wet delay (ZWD) which is

Michael Bevis; Steven Businger; Thomas A. Herring; Christian Rocken; Richard A. Anthes; Randolph H. Ware

1992-01-01

409

Applications of Global Positioning System (GPS) in geodynamics: with three examples from Turkey  

Microsoft Academic Search

Global Positioning System (GPS) has been very useful tool for the last two decades in the area of geodynamics because or the validation of the GPS results by the Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) observations. The modest budget requirement and the high accuracy relative positioning availability of GPS increased the use of it in determination

H. Yavasoglu; E. Tari; M. Sahin; H. Karaman; T. Erden; S. Bilgi; S. Erdogan

2005-01-01

410

Design and implementation of an automatic road network map processing system using GPS technology  

Microsoft Academic Search

Summary form only given. We present a reverse use of GPS technology. Instead of using a GPS receiver as a locator, we use it to create road network maps that contain different types of features such as crossovers, roundabouts, different street levels, and different lanes. The principle of our system consists mainly in: (1) collecting data using GPS technology; (2)

A. Touir; R. Zantout

2003-01-01

411

GPS Animations  

NSDL National Science Digital Library

This site features Flash animations that illustrate how the Global Positioning System (GPS) works. The animations depict how GPS signals are derived, compare geostationary and polar orbits, and explain satellites, ground control, and user segments, which comprise the three main GPS components. These resources are suitable for use in lectures, labs, or other teaching activities.

2008-09-12

412

Positional Accuracy of Airborne Integrated Global Positioning and Inertial Navigation Systems for Mapping in Glen Canyon, Arizona  

Microsoft Academic Search

ABSTRACT High-resolution airborne and satellite image sensor systems integrated with onboard data collection based on the Global Positioning System (GPS) and inertial navigation systems (INS) may offer a quick and cost-effective way to gather accurate topographic map information without ground control or aerial triangulation. The Applanix Corporation’s Position and Orientation Solutions for Direct Georeferencing of aerial photography,was used in this

Richard D. Sanchez; Larry D. Hothem

413

A novel laser Doppler velocimeter and its integrated navigation system with strapdown inertial navigation  

NASA Astrophysics Data System (ADS)

In order to suppress the error accumulation effect of inertial navigation system (INS), an idea of building an integrated navigation system using a laser Doppler velocimeter (LDV) together with strapdown inertial navigation (SIN) is proposed. The basic principle of LDV is expounded while a novel LDV with advanced optical structure is designed based on the split and reuse technique, and the process of dead reckoning using an integrated system which consists of LDV and SIN is discussed detailedly. The results of theory and experiment show that: the split and reuse type LDV has great advantages of high accuracy and signal-to-noise ratio, which has greatly enhanced the position accuracy of the navigation system. The position error has been decreased from 1166 m in 2 h with pure SIN to 20 m in 2 h with the integrated system.

Zhou, Jian; Nie, Xiaoming; Lin, Jun

2014-12-01

414

Optical Navigation System for Robotics Application  

Microsoft Academic Search

Frequently, robots find themselves asking this question. Knowing your location?? And being able to navigate to other locations is extremely important for autonomous robots. The act of finding one's location against a map is known as localization. So how can a robot localize itself? The most common form of intelligent localization and navigation is to use a map, combined with

Deepak Solanki; Vanchhit Khare

2012-01-01

415

Estimating Zenith Tropospheric Delays from BeiDou Navigation Satellite System Observations  

PubMed Central

The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages. PMID:23552104

Xu, Aigong; Xu, Zongqiu; Ge, Maorong; Xu, Xinchao; Zhu, Huizhong; Sui, Xin

2013-01-01

416

Estimating zenith tropospheric delays from BeiDou navigation satellite system observations.  

PubMed

The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages. PMID:23552104

Xu, Aigong; Xu, Zongqiu; Ge, Maorong; Xu, Xinchao; Zhu, Huizhong; Sui, Xin

2013-01-01

417

An Heuristic Method for GPS Surveying Stefka Fidanova  

E-print Network

, to analyze and improve the efficiency of the design of Global Positioning System (GPS) surveying networks of computational effort. The Global Positioning System is a satellite-based radio-navigation system that permits. The most widely known space systems are: the American Global Positioning System (GPS), the Russian GLObal

Fidanova, Stefka

418

A persuasive GPS-controlled thermostat system  

E-print Network

Using 10 weeks of data from a couple living in an instrumented home, we report on the potential of context-aware power management for energy saving. We identify an opportunity to save on heating and cooling using a system ...

Gupta, Manu, S. M. Massachusetts Institute of Technology

2008-01-01

419

Navigation systems for approach and landing of VTOL aircraft  

NASA Technical Reports Server (NTRS)

The formulation and implementation of navigation systems used for research investigations in the V/STOLAND avionics system are described. The navigation systems prove position and velocity in a cartestian reference frame aligned with the runway. They use filtering techniques to combine the raw position data from navaids (e.g., TACAN, MLS) with data from onboard inertial sensors. The filtering techniques which use both complementary and Kalman filters, are described. The software for the navigation systems is also described.

Schmidt, S. F.; Mohr, R. L.

1979-01-01

420

Pre-Flight Testing of Spaceborne GPS Receivers Using a GPS Constellation Simulator  

NASA Technical Reports Server (NTRS)

The NASA Goddard Space Flight Center (GSFC) Global Positioning System (GPS) test facility has been established within the GSFC Guidance Navigation and Control Center. The GPS test facility is currently housing the STR2760 GPS satellite 40-channel attitude simulator and an STR4760 12-channel navigation simulator. The facility also contains a few other Goddard resources such as an atomic time standard test bed, a rooftop antenna platform and a radome. It provides a new capability of high dynamics GPS simulations for space flight that is unique within the aerospace community. The GPS facility gives a significant advantage in the development and support of GPS based technologies for position, attitude and precise time determination on-board a spacecraft, sounding rocket or balloon. The GPS simulator system is configured in a transportable rack and is available for GPS applications' component development as well as for spacecraft subsystem and system level testing at spacecraft integration and test sites. The GPS facility has been operational since early 1996 and has been already utilized by a few successful flight projects carrying GPS experiments, such as USA Seastar satellite and the first Argentine satellite SAC-A. The experience in the SAC-A pre-flight testing using the STR2760 simulator is summarized as well as the comparison with preliminary analysis of the GPS data from SAC-A telemetry.

Kizhner, Semion; Alonso, Roberto

1999-01-01

421

Simulation Of Satellite Trajectories And Navigation  

NASA Technical Reports Server (NTRS)

Orbit Analysis and Simulation Software, OASIS, is software system developed for covariance and simulation analyses of problems involving Earth satellites, especially Global Positioning System (GPS). Provides flexible, versatile, and efficient software tool for analysis of accuracy in Earth-satellite navigation and GPS-based geodetic studies.

Wu, Sien-Chong; Bertiger, William I.; Border, James S.; Lichten, Stephen M.; Sunseri, Richard F.; Williams, Bobby G.; Wolff, Peter J.; Wu, Jiun-Tsong

1989-01-01

422

Observability Analysis of a MEMS INS/GPS Integration System with Gyroscope G-Sensitivity Errors.  

PubMed

Gyroscopes based on micro-electromechanical system (MEMS) technology suffer in high-dynamic applications due to obvious g-sensitivity errors. These errors can induce large biases in the gyroscope, which can directly affect the accuracy of attitude estimation in the integration of the inertial navigation system (INS) and the Global Positioning System (GPS). The observability determines the existence of solutions for compensating them. In this paper, we investigate the observability of the INS/GPS system with consideration of the g-sensitivity errors. In terms of two types of g-sensitivity coefficients matrix, we add them as estimated states to the Kalman filter and analyze the observability of three or nine elements of the coefficient matrix respectively. A global observable condition of the system is presented and validated. Experimental results indicate that all the estimated states, which include position, velocity, attitude, gyro and accelerometer bias, and g-sensitivity coefficients, could be made observable by maneuvering based on the conditions. Compared with the integration system without compensation for the g-sensitivity errors, the attitude accuracy is raised obviously. PMID:25171122

Fan, Chen; Hu, Xiaoping; He, Xiaofeng; Tang, Kanghua; Luo, Bing

2014-01-01

423

Observability Analysis of a MEMS INS/GPS Integration System with Gyroscope G-Sensitivity Errors  

PubMed Central

Gyroscopes based on micro-electromechanical system (MEMS) technology suffer in high-dynamic applications due to obvious g-sensitivity errors. These errors can induce large biases in the gyroscope, which can directly affect the accuracy of attitude estimation in the integration of the inertial navigation system (INS) and the Global Positioning System (GPS). The observability determines the existence of solutions for compensating them. In this paper, we investigate the observability of the INS/GPS system with consideration of the g-sensitivity errors. In terms of two types of g-sensitivity coefficients matrix, we add them as estimated states to the Kalman filter and analyze the observability of three or nine elements of the coefficient matrix respectively. A global observable condition of the system is presented and validated. Experimental results indicate that all the estimated states, which include position, velocity, attitude, gyro and accelerometer bias, and g-sensitivity coefficients, could be made observable by maneuvering based on the conditions. Compared with the integration system without compensation for the g-sensitivity errors, the attitude accuracy is raised obviously. PMID:25171122

Fan, Chen; Hu, Xiaoping; He, Xiaofeng; Tang, Kanghua; Luo, Bing

2014-01-01

424

Plot Your Course - Navigation  

NSDL National Science Digital Library

In this unit, students learn the very basics of navigation, including the different kinds of navigation and their purposes. The concepts of relative and absolute location, latitude, longitude and cardinal directions are explored, as well as the use and principles of maps and a compass. Students discover the history of navigation and learn the importance of math and how it ties into navigational techniques. Understanding how trilateration can determine one's location leads to a lesson on the global positioning system and how to use a GPS receiver. The unit concludes with an overview of orbits and spacecraft trajectories from Earth to other planets.

Integrated Teaching And Learning Program

425

REAL-TIME GPS SATELLITE SIGNAL SIMULATOR - SOFTWARE DESIGN ON A MULTI-SHARC PARALLEL PROCESSING SYSTEM  

Microsoft Academic Search

GPS (Global Positioning System) signal simulator is a versatile instrument used for testing and performance evaluation of GPS receiver during its design and manufacture. GPS Signal simulator outputs the L1 signal of GPS satellites as received by the GPS receiver at its antenna. The generation of GPS signal requires the transmission of L1 signal at a rate of 1.023 Mbits\\/sec

S. V. M. K. Prasad; T. Ananda; G. Boopalan; V. Vaidehi; P. V. Ramakrishna; C. N. Krishnan

426

A tactile communication system for navigation  

E-print Network

A vibrotactile display for use in navigation has been designed and evaluated. The arm and the torso, which offer relatively large and flat surface areas, were chosen as locations for the displays. The ability of subjects ...

Piateski, Erin M

2005-01-01

427

Institute of Navigation, Annual Meeting, 42nd, Seattle, WA, June 24-26, 1986, Proceedings  

SciTech Connect

The conference presents papers on the analysis of range and position comparison methods as a means of providing GPS integrity in the user receiver, a software package for predicting the performance of VLF-navigation systems, and measurement errors in GPS observables. Other topics include the architecture and performance of a real time differential GPS ground station, optimal locations of pseudolites for differential GPS, and GPS receiver technologies. Consideration is also given to Australian trials of Phase II Navstar GPS user equipment and the sensitivity of an autonomous navigation landmark tracing system due to the variability of landmark availability and distribution.

Not Available

1986-01-01

428

76 FR 12643 - Proposed Establishment of Helicopter Area Navigation (RNAV) Routes; Northeast United States  

Federal Register 2010, 2011, 2012, 2013

...helicopters having IFR- approved Global Positioning System (GPS)/Global Navigation Satellite System (GNSS) equipment...take advantage of developments in Performance Based Navigation technology. TK routes would be designated only within U.S....

2011-03-08

429

The REFSAT approach to low-cost GPS terminals  

NASA Technical Reports Server (NTRS)

A concept utilizing a geostationary reference satellite (REFSAT) that broadcasts navigation aiding signals to low cost civil user terminals which employ the constellation of 24 NAVSTAR Global Positioning System (GPS) satellites for position determination is described. The signal acquisition, tracking and position fixing properties of such low cost, dual channel, L-band, civil user receiver designed to receive both GPS navigation and REFSAT navigation aiding signals is presented. REFSAT reduces the cost of user equipment.

Sennott, J. W.; Choudhury, A. K.; Taylor, R. E.

1979-01-01

430

A Micromechanical INS/GPS System for Small Satellites  

NASA Technical Reports Server (NTRS)

The cost and complexity of large satellite space missions continue to escalate. To reduce costs, more attention is being directed toward small lightweight satellites where future demand is expected to grow dramatically. Specifically, micromechanical inertial systems and microstrip global positioning system (GPS) antennas incorporating flip-chip bonding, application specific integrated circuits (ASIC) and MCM technologies will be required. Traditional microsatellite pointing systems do not employ active control. Many systems allow the satellite to point coarsely using gravity gradient, then attempt to maintain the image on the focal plane with fast-steering mirrors. Draper's approach is to actively control the line of sight pointing by utilizing on-board attitude determination with micromechanical inertial sensors and reaction wheel control actuators. Draper has developed commercial and tactical-grade micromechanical inertial sensors, The small size, low weight, and low cost of these gyroscopes and accelerometers enable systems previously impractical because of size and cost. Evolving micromechanical inertial sensors can be applied to closed-loop, active control of small satellites for micro-radian precision-pointing missions. An inertial reference feedback control loop can be used to determine attitude and line of sight jitter to provide error information to the controller for correction. At low frequencies, the error signal is provided by GPS. At higher frequencies, feedback is provided by the micromechanical gyros. This blending of sensors provides wide-band sensing from dc to operational frequencies. First order simulation has shown that the performance of existing micromechanical gyros, with integrated GPS, is feasible for a pointing mission of 10 micro-radians of jitter stability and approximately 1 milli-radian absolute error, for a satellite with 1 meter antenna separation. Improved performance micromechanical sensors currently under development will be suitable for a range of micro-nano-satellite applications.

Barbour, N.; Brand, T.; Haley, R.; Socha, M.; Stoll, J.; Ward, P.; Weinberg, M.

1995-01-01

431

INTRODUCTION The integration of GPS receivers with inertial  

E-print Network

INTRODUCTION The integration of GPS receivers with inertial navigation systems (INS) has been well only at using high-end, navigation-grade inertial systems for high-accuracy (centimeter with inertial sensors can provide many benefits for navigation, from improved accuracy to increased reliability

Calgary, University of

432

A precise GPS-based time and frequency system  

NASA Technical Reports Server (NTRS)

An approach to implementing a compact, highly reliable and precise Master Time and Frequency subsystem usable in a variety of applications is described. These applications include, among others, Satellite Ground Terminals, Range Timing Stations, Communications Terminals, and Power Station Timing subsystems. All time and frequency output signals are locked to Universal Time via the GPS Satellite system. The system provides for continued output of precise signals in the event of GPS signal interruption from antenna or lead-in breakage or other causes. Cost/performance tradeoffs affecting system accuracy over the short, medium, and long term are discussed. A unique approach to redundant system design provides an architecture with the reliability advantage of triple-redundant majority voting and the cost advantages of dual-redundant elements. The system can be configured to output a variety of precise time and frequency signals and the design can be tailored to output as few, or as many, types and quantities of signals as are required by the application.

Mcnabb, Jack; Fossler, Earl

1993-01-01

433

75 FR 47252 - Proposed Establishment of Low Altitude Area Navigation Routes (T-281, T-283, T-285, T-286, and T...  

Federal Register 2010, 2011, 2012, 2013

...Low Altitude Area Navigation Routes (T- 281...low altitude Area Navigation (RNAV) routes...RNAV, for use by aircraft that have instrument...Global Positioning System (GPS)/Global Navigation Satellite...

2010-08-05

434

76 FR 5068 - Establishment of Low Altitude Area Navigation Routes (T-281, T-283, T-285, T-286, and T-288...  

Federal Register 2010, 2011, 2012, 2013

...Low Altitude Area Navigation Routes (T-281...low altitude Area Navigation (RNAV) routes...RNAV, for use by aircraft that have instrument...Global Positioning System (GPS)/Global Navigation Satellite...

2011-01-28

435

Behavioral VHDL implementation of coherent digital GPS signal receiver  

Microsoft Academic Search

Global Positioning System is a technology which is gaining acceptance. Originally developed for military purposes, it is being used in civilian applications such as navigation, emergency services, etc. A system-on-chip application merges different functions and applications on a single substrate. This project models a GPS receiver for a system on chip application. The GPS receiver, developed as a core, is

Viswanath Daita

2004-01-01

436

Study on GPS-based portable field rescue positioning system  

Microsoft Academic Search

The paper presents a GPS-based positioning method mainly used to field rescue. The position and orientation of the rescuer and the trapped are acquired using GPS chip and digital compass. Using the GPS data and compass data, the relative distance and orientation between them are calculated from the geometric relationships based on a series of formulas in Geographic Information Science

Xiao Luo; Jiandong Zhao; Yichao Liu

2010-01-01

437

Study on Initial Alignment for Inertial Navigation System  

Microsoft Academic Search

The algorithms and the applications of static base initial alignment method of inertial navigation system are presented. Kalman filtering is used in initial alignment method. The math platform error angles ¿N, ¿E, ¿D are estimated form random error and random disturbance, while the gyro drifts and accelerometer bias are estimated, and the system platform coordinate and navigation coordinate are alignment

Li Qing; Yang PeiPei

2009-01-01

438

Tightly Coupled Visual-Inertial Navigation System Using Optical Flow  

E-print Network

Tightly Coupled Visual-Inertial Navigation System Using Optical Flow Simon Lynen Sammy Omari correctly, even in presence of substantial initial state errors. The minimal sensor suite, which is both light-weight and low-cost, renders the framework an appealing choice for the use as a navigation system

Daraio, Chiara

439

MDB: A design tool for integrated navigation systems  

NASA Astrophysics Data System (ADS)

The design of an integrated navigation system requires that various aspects are taken into consideration. In this paper the aspect of reliability (in the statistical sense) is more closely investigated. A particular measure of reliability, the Minimal Detectable Bias (MDB), is considered. Its use as a design tool for integrated navigation systems is described and is illustrated by an example.

Salzmann, Martin

1991-06-01

440

Precision hybrid navigation system for varied marine applications  

Microsoft Academic Search

A need has long been established to provide low cost precise inertial and integrated navigation systems for seaborne applications. The adaptation of low cost, high volume electronics and inertial sensors from Kearfott missile and land products has enabled this need to become a reality. The development of a low power navigation system for guidance of Unmanned Underwater Vehicles used in

S. Beiter; R. Poquette; B. S. Filipo; W. Goetz

1998-01-01

441

An aircraft Kalman filter integrated navigation system prototype  

Microsoft Academic Search

An experimental Kalman filter integrated navigation and position determination system is presented. The system operates on a distributed computer installed in a Convair 580 aircraft, for use in scientific research in the areas of geophysics, oceanography, and advanced navigation. Representative results which show the operation of the prototype during tests of some of its failure modes are presented

J. E. Jordan; C. D. Hardwick; B. W. Leach

1991-01-01

442

A Lightweight and Self-Contained Airborne Navigational System  

Microsoft Academic Search

The paper discusses the design of a self-contained navigational aid for aircraft. There are many techniques and variations upon which such a system may be based. The one chosen for discussion is a hybrid system which combines an inertial north reference, a Doppler navigational radar, and an airspeed indicator. A velocity triangle computer relates these three sources of input data,

R. K. Brown; N. F. Moody; P. M. Thompson; R. J. Bibby; C. A. Franklin; J. H. Ganton; J. Mitchell

1959-01-01

443

Optimal terrain-aided navigation systems  

Microsoft Academic Search

The basic framework for applying Kalman filtering techniques to radar terrain-clearance data is investigated. By recursively Kalman processing each individual radar measurement separately, a whole new class of terrain-aided navigation schemes becomes available which in the past could not be developed using simple correlation algorithms. To diminish the effect of terrain nonlinearities, adaptive stochastic linearization techniques are utilized in a

Hostetler

1978-01-01

444

The Navigation System of the JPL Robot  

Microsoft Academic Search

The control structure of the JPL research robot and the operations of the navigation subsys­ tem are discussed. The robot functions as a network of interacting concurrent processes dis­ tributed among several computers and coordinated by a central executive. The results of scene analysis are used to create a segmented terrain model in which surface regions are classified by traversibility.

Alan M. Thompson

1977-01-01

445

Fiber-based rotary strapdown inertial navigation system  

NASA Astrophysics Data System (ADS)

Navigation involves the integration of methodologies and systems for estimating the time-varying attitude of moving objects. A fiber strapdown inertial navigation system (FSINS) is presently used in several applications related to vehicle navigation. However, the absolute attitude and position from FSINS contain an error that increases with time. In order to improve the performance of FSINS based on our present inertial sensors, the auto-compensation of inertial sensor bias in rotation error modulation was proposed. The aim is to develop a rotary FSINS, in which the significant sensor bias is automatically compensated by rotating the inertial measurement unit (IMU), to offer the comparable navigation performance to navigation-grade IMU. In the proposed rotational technology, the IMU is rotated back and forth in azimuth through four orthogonal positions relative to the vehicle's longitudinal axis. Simulation and experimental testing are conducted for the prototype, and the results showed that the rotary FSINS's navigation performance is improved.

Sun, Wei; Gao, Yang

2013-07-01

446

33 CFR 207.275 - McClellan-Kerr Arkansas River navigation system: use, administration, and navigation.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false McClellan-Kerr Arkansas River navigation system: use, administration...207.275 McClellan-Kerr Arkansas River navigation system: use, administration...in the following waterways: The White River between Mississippi River and...

2010-07-01

447

33 CFR 207.275 - McClellan-Kerr Arkansas River navigation system: use, administration, and navigation.  

...2014-07-01 false McClellan-Kerr Arkansas River navigation system: use, administration...207.275 McClellan-Kerr Arkansas River navigation system: use, administration...in the following waterways: The White River between Mississippi River and...

2014-07-01

448

GPS: History, Operation, Processing Important Dates  

E-print Network

: Initial measurements by academic institutions; start · Mid-1990's: Receiver costs drop substantially be decoded by is what all civilian navigation systems use. · P code, on both the L1 and L2 frequencies on the receiver clock. Note that we use superscripts for satellites, subscripts for receiv #12;GPS for Navigation

Fialko, Yuri

449

Leica System 1200: Towards Sensor Synchronization of GPS and TPS for Kinematic Applications  

E-print Network

Leica System 1200: Towards Sensor Synchronization of GPS and TPS for Kinematic Applications Werner Stempfhuber and Thomas Wunderlich 1 Introduction Modern measurement systems such as the robot tacheometer (Terrestrial Positioning System, TPS) or the " Glo- bal Positioning System (GPS)" allow discrete and high

450

Enhancing positioning accuracy in urban terrain by fusing data from a GPS receiver, inertial sensors, stereo-camera and digital maps for pedestrian navigation.  

PubMed

The paper presents an algorithm for estimating a pedestrian location in an urban environment. The algorithm is based on the particle filter and uses different data sources: a GPS receiver, inertial sensors, probability maps and a stereo camera. Inertial sensors are used to estimate a relative displacement of a pedestrian. A gyroscope estimates a change in the heading direction. An accelerometer is used to count a pedestrian's steps and their lengths. The so-called probability maps help to limit GPS inaccuracy by imposing constraints on pedestrian kinematics, e.g., it is assumed that a pedestrian cannot cross buildings, fences etc. This limits position inaccuracy to ca. 10 m. Incorporation of depth estimates derived from a stereo camera that are compared to the 3D model of an environment has enabled further reduction of positioning errors. As a result, for 90% of the time, the algorithm is able to estimate a pedestrian location with an error smaller than 2 m, compared to an error of 6.5 m for a navigation based solely on GPS. PMID:22969321

Przemyslaw, Baranski; Pawel, Strumillo

2012-01-01

451

GPS: primary tool for time transfer  

Microsoft Academic Search

The Global Positioning System (GPS) is not only a navigation system, it is also a time-transfer system. As a time-transfer system it provides stability very close to one part in ten to the fourteenth over one day (1 ns\\/day). After a brief introduction to timekeeping terms, this paper reviews the role of GPS in time distribution and clock synchronization. The

WLODZIMIERZ LEWANDOWSKI; JACQUES AZOUBIB; WILLIAM J. KLEPCZYNSKI

1999-01-01

452

Pharos: coupling GSM and GPS-TALK technologies to provide orientation, navigation and location-based services for the blind  

Microsoft Academic Search

Millions of people are already experiencing with GSM the freedom of going mobile for voice and Internet access. This freedom is reshaping every aspect of our lives; the way we do business, the way we buy things and the way we communicate. For the blind, when combined with GPS, it could also add the freedom of movement. The paper considers

A. Marsh; M. May; M. Saarelainen

2000-01-01

453

Comparative advantage between traditional and smart navigation systems  

NASA Astrophysics Data System (ADS)

The smart navigation system that refers to real-time traffic data is believed to be superior to traditional navigation systems. To verify this belief, we created an agent-based traffic model and examined the effect of changing market share of the traditional shortest-travel-time algorithm based navigation and the smart navigation system. We tested our model on the grid and actual metropolitan road network structures. The result reveals that the traditional navigation system have better performance than the smart one as the market share of the smart navigation system exceeds a critical value, which is contrary to conventional expectation. We suggest that the superiority inversion between agent groups is strongly related to the traffic weight function form, and is general. We also found that the relationship of market share, traffic flow density and travel time is determined by the combination of congestion avoidance behavior of the smartly navigated agents and the inefficiency of shortest-travel-time based navigated agents. Our results can be interpreted with the minority game and extended to the diverse topics of opinion dynamics.

Shin, Jeongkyu; Kim, Pan-Jun; Kim, Seunghwan

2013-03-01

454

IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, VOL. 19, NO. 1, FEBRUARY 2003 15 Autonomous Vehicle Positioning With GPS in  

E-print Network

--The Global Positioning System (GPS) has been widely used in land vehicle navigation applications. However problems successfully. Index Terms--Extended Kalman filtering, Global Positioning System (GPS), interacting multiple model, joint parameter and state estimation. I. INTRODUCTION THE GLOBAL Positioning System (GPS

Ge, Shuzhi Sam

455

Initial alignment of a gimballess inertial navigation system  

Microsoft Academic Search

Initial alignment of gyrostabilized platforms is accomplished by gyrocompassing techniques. These cannot be used in the case of strap-down systems (gimballess inertial navigation systems) where the inertial components are \\

V. Krishnan; K. Grobert

1970-01-01

456

GPS-Optimal Micro Air Vehicle Navigation in Degraded Environments* Jason T. Isaacs1, Ceridwen Magee2, Anantharaman Subbaraman1, Francois Quitin3, Kingsley Fregene2,  

E-print Network

to their lower size, weight, required power, cost and ease of deployment/maintenance, the class of UAS for radio frequency (RF) source-seeking with a single-wing rotating micro air vehicle (MAV) operating of operating in an urban canyon environment. First, Global Positioning System (GPS) localization quality can

Hespanha, João Pedro

457

Strapdown inertial navigation system algorithms based on dual quaternions  

Microsoft Academic Search

The design of strapdown inertial navigation system (INS) algorithms based on dual quaternions is addressed. Dual quaternion is a most concise and efficient mathematical tool to represent rotation and translation simultaneously, i.e., the general displacement of a rigid body. The principle of strapdown inertial navigation is represented using the tool of dual quaternion. It is shown that the principle can

Yuanxin Wu; Xiaoping Hu; Dewen Hu; Tao Li; Junxiang Lian

2005-01-01

458

INFSCI 2480: Adaptive Information Systems Adaptive Navigation Support  

E-print Network

support ­ link adaptation #12;Adaptive hypermedia technologies Adaptive presentation Adaptive navigationINFSCI 2480: Adaptive Information Systems Adaptive Navigation Support Peter Brusilovsky School of Information Sciences University of Pittsburgh, USA http://www.sis.pitt.edu/~peterb/ A Part of Adaptive

Brusilovsky, Peter

459

STATIC INITIAL AZIMUTH UPDATE METHOD IN LAND NAVIGATION SYSTEMS  

Microsoft Academic Search

The paper presents a method for the initial azimuth selection in Land Navigation Systems (LNS), applying the ZUPT (Zero-velocity UPdaTe) technique. This technique is understood as a correction of the initial setting achieve the best accuracy of the navigation. The case of the inaccurate initial azimuth during stopping of the vehicle (after short drive) in order to setting is considered.

Jacek Szymanowski

460

New techniques for initial alignment of strapdown inertial navigation system  

Microsoft Academic Search

Some new techniques for initial alignment of strapdown inertial navigation system are proposed in this paper. A new solution for the precise azimuth alignment is given in detail. A new prefilter, which consists of an IIR filter and a Kalman filter using hidden Markov model, is designed to attenuate the influence of sensor noise and outer disturbance. Navigation algorithm in

Shaolin Lü; Ling Xie; Jiabin Chen

2009-01-01

461

Road Navigation System Monitoring using a Pseudorange Snapshot Test  

E-print Network

Road Navigation System Monitoring using a Pseudorange Snapshot Test Cl´ement Fouque Philippe`egne Cedex, France clement.fouque@hds.utc.fr , philippe.bonnifait@hds.utc.fr Abstract: Global Navigation provided by a digital road network. Using the positioning residuals of map-aided GNSS, a new method

Boyer, Edmond

462

Regionalized Lunar South Pole Surface Navigation System Analysis  

NASA Technical Reports Server (NTRS)

Apollo missions utilized Earth-based assets for navigation because the landings took place at lunar locations in constant view from the Earth. The new exploration campaign to the lunar south pole region will have limited Earth visibility, but the extent to which a navigation system comprised solely of Earth-based tracking stations will provide adequate navigation solutions in this region is unknown. This report presents a dilution-of-precision (DoP)-based, stationary surface navigation analysis of the performance of multiple lunar satellite constellations, Earth-based deep space network assets, and combinations thereof. Results show that kinematic and integrated solutions cannot be provided by the Earth-based deep space network stations. Also, the stationary surface navigation system needs to be operated either as a two-way navigation system or as a one-way navigation system with local terrain information, while the position solution is integrated over a short duration of time with navigation signals being provided by a lunar satellite constellation.

Welch, Bryan W.

2008-01-01

463

BROADCASTING GPS INTEGRITY INFORMATION USING LORAN-C  

E-print Network

BROADCASTING GPS INTEGRITY INFORMATION USING LORAN-C A DISSERTATION SUBMITTED TO THE DEPARTMENT © Copyright 2002 Sherman C. Lo, All Rights Reserved #12;iii I certify that I have read this thesis Positioning System (GPS) as its primary navigation systems for aviation as stated by the Federal

Stanford University

464

Application of GPS attitude determination to gravity gradient stabilized spacecraft  

NASA Technical Reports Server (NTRS)

Recent advances in the Global Positioning System (GPS) technology have initiated a new era in aerospace navigation and control. GPS receivers have become increasingly compact and affordable, and new developments have made attitude determination using subcentimeter positioning among two or more antennas feasible for real-time applications. GPS-based attitude control systems will become highly portable packages which provide time, navigation, and attitude information of sufficient accuracy for many aerospace needs. A typical spacecraft application of GPS attitude determination is a gravity gradient stabilized satellite in low Earth orbit that employs a GPS receiver and four body mounted patch antennas. The coupled, linearized equations of motion enable complete position and attitude information to be extracted from only two antennas. A discussion of the various error sources for spaceborne GPS attitude measurement systems is included. Attitude determination of better than 0.3 degrees is possible for 1 meter antenna separation. Suggestions are provided to improve the accuracy of the attitude solution.

Lightsey, E. G.; Cohen, Clark E.; Parkinson, Bradford W.

1993-01-01

465

Intelligent personal navigator supported by knowledge-based systems for estimating dead reckoning navigation parameters  

Microsoft Academic Search

Personal navigators (PN) have been studied for about a decade in different fields and applications, such as safety and rescue operations, security and emergency services, and police and military applications. The common goal of all these applications is to provide precise and reliable position, velocity, and heading information of each individual in various environments. In the PN system developed in

Shahram Moafipoor

2010-01-01

466