Experimental investigation of a quad-rotor biplane micro air vehicle

NASA Astrophysics Data System (ADS)

Bogdanowicz, Christopher Michael

Micro air vehicles are expected to perform demanding missions requiring efficient operation in both hover and forward flight. This thesis discusses the development of a hybrid air vehicle which seamlessly combines both flight capabilities: hover and high-speed forward flight. It is the quad-rotor biplane, which weighs 240 grams and consists of four propellers with wings arranged in a biplane configuration. The performance of the vehicle system was investigated in conditions representative of flight through a series of wind tunnel experiments. These studies provided an understanding of propeller-wing interaction effects and system trim analysis. This showed that the maximum speed of 11 m/s and a cruise speed of 4 m/s were achievable and that the cruise power is approximately one-third of the hover power. Free flight testing of the vehicle successfully highlighted its ability to achieve equilibrium transition flight. Key design parameters were experimentally investigated to understand their effect on overall performance. It was found that a trade-off between efficiency and compactness affects the final choice of the design. Design improvements have allowed for decreases in vehicle weight and ground footprint, while increasing structural soundness. Numerous vehicle designs, models, and flight tests have proven system scalability as well as versatility, including an upscaled model to be utilized in an extensive commercial package delivery system. Overall, the quad-rotor biplane is proven to be an efficient and effective multi-role vehicle.

Model Identification and Control System Design for the Lambda Unmanned Research Vehicle

DTIC Science & Technology

1991-09-01

AD-A241 859 D T IC_ _ _ _ _ __ OCT 21921MODEL IDENTIFICATION AND CONTROL SYSTEM DESIGN FOR THE LAMBDA UNMANNED RESEARCH VEHICLE: THESIS Gerald A...23 191K MODEL IDENTIFICATION AND CONTROL SYSTEM DESIGN FOR THE LAMBDA UNMANNED RESEARCH VEHICLE THESIS Gerald A. Swift, First Lieutenant, USAF AFIT...UNMANNED RESEARCH VEHICLE THESIS Presented to the Faculty of the School of Engineering of the Air Force Institute of Technology Air University in Partial

Air-Breathing Launch Vehicle Technology Being Developed

NASA Technical Reports Server (NTRS)

Trefny, Charles J.

2003-01-01

Of the technical factors that would contribute to lowering the cost of space access, reusability has high potential. The primary objective of the GTX program is to determine whether or not air-breathing propulsion can enable reusable single-stage-to-orbit (SSTO) operations. The approach is based on maturation of a reference vehicle design with focus on the integration and flight-weight construction of its air-breathing rocket-based combined-cycle (RBCC) propulsion system.

Control and design of multiple unmanned air vehicles for persistent surveillance

NASA Astrophysics Data System (ADS)

Nigam, Nikhil

Control of multiple autonomous aircraft for search and exploration, is a topic of current research interest for applications such as weather monitoring, geographical surveys, search and rescue, tactical reconnaissance, and extra-terrestrial exploration, and the need to distribute sensing is driven by considerations of efficiency, reliability, cost and scalability. Hence, this problem has been extensively studied in the fields of controls and artificial intelligence. The task of persistent surveillance is different from a coverage/exploration problem, in that all areas need to be continuously searched, minimizing the time between visitations to each region in the target space. This distinction does not allow a straightforward application of most exploration techniques to the problem, although ideas from these methods can still be used. The use of aerial vehicles is motivated by their ability to cover larger spaces and their relative insensitivity to terrain. However, the dynamics of Unmanned Air Vehicles (UAVs) adds complexity to the control problem. Most of the work in the literature decouples the vehicle dynamics and control policies, but their interaction is particularly interesting for a surveillance mission. Stochastic environments and UAV failures further enrich the problem by requiring the control policies to be robust, and this aspect is particularly important for hardware implementations. For a persistent mission, it becomes imperative to consider the range/endurance constraints of the vehicles. The coupling of the control policy with the endurance constraints of the vehicles is an aspect that has not been sufficiently explored. Design of UAVs for desirable mission performance is also an issue of considerable significance. The use of a single monolithic optimization for such a problem has practical limitations, and decomposition-based design is a potential alternative. In this research high-level control policies are devised, that are scalable, reliable

A Discussion of Aerodynamic Control Effectors (ACEs) for Unmanned Air Vehicles (UAVs)

NASA Technical Reports Server (NTRS)

Wood, Richard M.

2002-01-01

A Reynolds number based, unmanned air vehicle classification structure has been developed which identifies four classes of unmanned air vehicle concepts. The four unmanned air vehicle (UAV) classes are; Micro UAV, Meso UAV, Macro UAV, and Mega UAV. In a similar fashion a labeling scheme for aerodynamic control effectors (ACE) was developed and eleven types of ACE concepts were identified. These eleven types of ACEs were laid out in a five (5) layer scheme. The final section of the paper correlated the various ACE concepts to the four UAV classes and ACE recommendations are offered for future design activities.

Conceptual design of two-stage-to-orbit hybrid launch vehicle

NASA Technical Reports Server (NTRS)

1991-01-01

The object of this design class was to design an earth-to orbit vehicle to replace the present NASA space shuttle. The major motivations for designing a new vehicle were to reduce the cost of putting payloads into orbit and to design a vehicle that could better service the space station with a faster turn-around time. Another factor considered in the design was that near-term technology was to be used. Materials, engines and other important technologies were to be realized in the next 10 to 15 years. The first concept put forth by NASA to meet these objectives was the National Aerospace Plane (NASP). The NASP is a single-stage earth-to-orbit air-breathing vehicle. This concept ran into problems with the air-breathing engine providing enough thrust in the upper atmosphere, among other things. The solution of this design class is a two-stage-to-orbit vehicle. The first stage is air-breathing and the second stage is rocket-powered, similar to the space shuttle. The second stage is mounted on the top of the first stage in a piggy-back style. The vehicle takes off horizontally using only air-breathing engines, flies to Mach six at 100,000 feet, and launches the second stage towards its orbital path. The first stage, or booster, will weigh approximately 800,000 pounds and the second stage, or orbiter will weigh approximately 300,000 pounds. The major advantage of this design is the full recoverability of the first stage compared with the present solid rocket booster that are only partially recoverable and used only a few times. This reduces the cost as well as providing a more reliable and more readily available design for servicing the space station. The booster can fly an orbiter up, turn around, land, refuel, and be ready to launch another orbiter in a matter of hours.

Analytical Studies of the Lift and Roll Stability of a Ram Air Cushion Vehicle

DOT National Transportation Integrated Search

1972-12-01

A ram air cushion vehicle (a type of ram wing) is described schematically and compared with a conventional air cushion vehicle design. The nonlinear equations for the flow in the cushion region are derived. A review is made of the most recent literat...

Flexible Wing Base Micro Aerial Vehicles: Composite Materials for Micro Air Vehicles

NASA Technical Reports Server (NTRS)

Ifju, Peter G.; Ettinger, Scott; Jenkins, David; Martinez, Luis

2002-01-01

This paper will discuss the development of the University of Florida's Micro Air Vehicle concept. A series of flexible wing based aircraft that possess highly desirable flight characteristics were developed. Since computational methods to accurately model flight at the low Reynolds numbers associated with this scale are still under development, our effort has relied heavily on trial and error. Hence a time efficient method was developed to rapidly produce prototype designs. The airframe and wings are fabricated using a unique process that incorporates carbon fiber composite construction. Prototypes can be fabricated in around five man-hours, allowing many design revisions to be tested in a short period of time. The resulting aircraft are far more durable, yet lighter, than their conventional counterparts. This process allows for thorough testing of each design in order to determine what changes were required on the next prototype. The use of carbon fiber allows for wing flexibility without sacrificing durability. The construction methods developed for this project were the enabling technology that allowed us to implement our designs. The resulting aircraft were the winning entries in the International Micro Air Vehicle Competition for the past two years. Details of the construction method are provided in this paper along with a background on our flexible wing concept.

Geometry Modeling and Adaptive Control of Air-Breathing Hypersonic Vehicles

NASA Astrophysics Data System (ADS)

Vick, Tyler Joseph

Air-breathing hypersonic vehicles have the potential to provide global reach and affordable access to space. Recent technological advancements have made scramjet-powered flight achievable, as evidenced by the successes of the X-43A and X-51A flight test programs over the last decade. Air-breathing hypersonic vehicles present unique modeling and control challenges in large part due to the fact that scramjet propulsion systems are highly integrated into the airframe, resulting in strongly coupled and often unstable dynamics. Additionally, the extreme flight conditions and inability to test fully integrated vehicle systems larger than X-51 before flight leads to inherent uncertainty in hypersonic flight. This thesis presents a means to design vehicle geometries, simulate vehicle dynamics, and develop and analyze control systems for hypersonic vehicles. First, a software tool for generating three-dimensional watertight vehicle surface meshes from simple design parameters is developed. These surface meshes are compatible with existing vehicle analysis tools, with which databases of aerodynamic and propulsive forces and moments can be constructed. A six-degree-of-freedom nonlinear dynamics simulation model which incorporates this data is presented. Inner-loop longitudinal and lateral control systems are designed and analyzed utilizing the simulation model. The first is an output feedback proportional-integral linear controller designed using linear quadratic regulator techniques. The second is a model reference adaptive controller (MRAC) which augments this baseline linear controller with an adaptive element. The performance and robustness of each controller are analyzed through simulated time responses to angle-of-attack and bank angle commands, while various uncertainties are introduced. The MRAC architecture enables the controller to adapt in a nonlinear fashion to deviations from the desired response, allowing for improved tracking performance, stability, and

Design Evolution and Performance Characterization of the GTX Air-Breathing Launch Vehicle Inlet

NASA Technical Reports Server (NTRS)

DeBonis, J. R.; Steffen, C. J., Jr.; Rice, T.; Trefny, C. J.

2002-01-01

The design and analysis of a second version of the inlet for the GTX rocket-based combine-cycle launch vehicle is discussed. The previous design did not achieve its predicted performance levels due to excessive turning of low-momentum comer flows and local over-contraction due to asymmetric end-walls. This design attempts to remove these problems by reducing the spike half-angle to 10- from 12-degrees and by implementing true plane of symmetry end-walls. Axisymmetric Reynolds-Averaged Navier-Stokes simulations using both perfect gas and real gas, finite rate chemistry, assumptions were performed to aid in the design process and to create a comprehensive database of inlet performance. The inlet design, which operates over the entire air-breathing Mach number range from 0 to 12, and the performance database are presented. The performance database, for use in cycle analysis, includes predictions of mass capture, pressure recovery, throat Mach number, drag force, and heat load, for the entire Mach range. Results of the computations are compared with experimental data to validate the performance database.

Autonomous unmanned air vehicles (UAV) techniques

NASA Astrophysics Data System (ADS)

Hsu, Ming-Kai; Lee, Ting N.

2007-04-01

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

Preliminary performance estimates of an oblique, all-wing, remotely piloted vehicle for air-to-air combat

NASA Technical Reports Server (NTRS)

Nelms, W. P., Jr.; Bailey, R. O.

1974-01-01

A computerized aircraft synthesis program has been used to assess the effects of various vehicle and mission parameters on the performance of an oblique, all-wing, remotely piloted vehicle (RPV) for the highly maneuverable, air-to-air combat role. The study mission consists of an outbound cruise, an acceleration phase, a series of subsonic and supersonic turns, and a return cruise. The results are presented in terms of both the required vehicle weight to accomplish this mission and the combat effectiveness as measured by turning and acceleration capability. This report describes the synthesis program, the mission, the vehicle, and results from sensitivity studies. An optimization process has been used to establish the nominal RPV configuration of the oblique, all-wing concept for the specified mission. In comparison to a previously studied conventional wing-body canard design for the same mission, this oblique, all-wing nominal vehicle is lighter in weight and has higher performance.

Optimization design and dynamic analysis on the drive mechanisms of flapping-wing air vehicles based on flapping trajectories

NASA Astrophysics Data System (ADS)

Xie, Lingwang; Zhang, Xingwei; Luo, Pan; Huang, Panpan

2017-10-01

The optimization designs and dynamic analysis on the driving mechanism of flapping-wing air vehicles on base of flapping trajectory patterns is carried out in this study. Three different driving mechanisms which are spatial double crank-rocker, plane five-bar and gear-double slider, are systematically optimized and analysed by using the Mat lab and Adams software. After a series debugging on the parameter, the comparatively ideal flapping trajectories are obtained by the simulation of Adams. Present results indicate that different drive mechanisms output different flapping trajectories and have their unique characteristic. The spatial double crank-rocker mechanism can only output the arc flapping trajectory and it has the advantages of small volume, high flexibility and efficient space utilization. Both planar five-bar mechanism and gear-double slider mechanism can output the oval, figure of eight and double eight flapping trajectories. Nevertheless, the gear-double slider mechanism has the advantage of convenient parameter setting and better performance in output double eight flapping trajectory. This study can provide theoretical basis and helpful reference for the design of the drive mechanisms of flapping-wing air vehicles with different output flapping trajectories.

Intelligence Applied to Air Vehicles

NASA Technical Reports Server (NTRS)

Rosen, Robert; Gross, Anthony R.; Fletcher, L. Skip; Zornetzer, Steven (Technical Monitor)

2000-01-01

The exponential growth in information technology has provided the potential for air vehicle capabilities that were previously unavailable to mission and vehicle designers. The increasing capabilities of computer hardware and software, including new developments such as neural networks, provide a new balance of work between humans and machines. This paper will describe several NASA projects, and review results and conclusions from ground and flight investigations where vehicle intelligence was developed and applied to aeronautical and space systems. In the first example, flight results from a neural network flight control demonstration will be reviewed. Using, a highly-modified F-15 aircraft, a NASA/Dryden experimental flight test program has demonstrated how the neural network software can correctly identify and respond to changes in aircraft stability and control characteristics. Using its on-line learning capability, the neural net software would identify that something in the vehicle has changed, then reconfigure the flight control computer system to adapt to those changes. The results of the Remote Agent software project will be presented. This capability will reduce the cost of future spacecraft operations as computers become "thinking" partners along with humans. In addition, the paper will describe the objectives and plans for the autonomous airplane program and the autonomous rotorcraft project. Technologies will also be developed.

Air change rates of motor vehicles and in-vehicle pollutant concentrations from secondhand smoke.

PubMed

Ott, Wayne; Klepeis, Neil; Switzer, Paul

2008-05-01

The air change rates of motor vehicles are relevant to the sheltering effect from air pollutants entering from outside a vehicle and also to the interior concentrations from any sources inside its passenger compartment. We made more than 100 air change rate measurements on four motor vehicles under moving and stationary conditions; we also measured the carbon monoxide (CO) and fine particle (PM(2.5)) decay rates from 14 cigarettes smoked inside the vehicle. With the vehicle stationary and the fan off, the ventilation rate in air changes per hour (ACH) was less than 1 h(-1) with the windows closed and increased to 6.5 h(-1) with one window fully opened. The vehicle speed, window position, ventilation system, and air conditioner setting was found to affect the ACH. For closed windows and passive ventilation (fan off and no recirculation), the ACH was linearly related to the vehicle speed over the range from 15 to 72 mph (25 to 116 km h(-1)). With a vehicle moving, windows closed, and the ventilation system off (or the air conditioner set to AC Max), the ACH was less than 6.6 h(-1) for speeds ranging from 20 to 72 mph (32 to 116 km h(-1)). Opening a single window by 3'' (7.6 cm) increased the ACH by 8-16 times. For the 14 cigarettes smoked in vehicles, the deposition rate k and the air change rate a were correlated, following the equation k=1.3a (R(2)=82%; n=14). With recirculation on (or AC Max) and closed windows, the interior PM(2.5) concentration exceeded 2000 microg m(-3) momentarily for all cigarettes tested, regardless of speed. The concentration time series measured inside the vehicle followed the mathematical solutions of the indoor mass balance model, and the 24-h average personal exposure to PM(2.5) could exceed 35 microg m(-3) for just two cigarettes smoked inside the vehicle.

Performance Validation Approach for the GTX Air-Breathing Launch Vehicle

NASA Technical Reports Server (NTRS)

Trefny, Charles J.; Roche, Joseph M.

2002-01-01

The primary objective of the GTX effort is to determine whether or not air-breathing propulsion can enable a launch vehicle to achieve orbit in a single stage. Structural weight, vehicle aerodynamics, and propulsion performance must be accurately known over the entire flight trajectory in order to make a credible assessment. Structural, aerodynamic, and propulsion parameters are strongly interdependent, which necessitates a system approach to design, evaluation, and optimization of a single-stage-to-orbit concept. The GTX reference vehicle serves this purpose, by allowing design, development, and validation of components and subsystems in a system context. The reference vehicle configuration (including propulsion) was carefully chosen so as to provide high potential for structural and volumetric efficiency, and to allow the high specific impulse of air-breathing propulsion cycles to be exploited. Minor evolution of the configuration has occurred as analytical and experimental results have become available. With this development process comes increasing validation of the weight and performance levels used in system performance determination. This paper presents an overview of the GTX reference vehicle and the approach to its performance validation. Subscale test rigs and numerical studies used to develop and validate component performance levels and unit structural weights are outlined. The sensitivity of the equivalent, effective specific impulse to key propulsion component efficiencies is presented. The role of flight demonstration in development and validation is discussed.

Design optimization of space launch vehicles using a genetic algorithm

NASA Astrophysics Data System (ADS)

Bayley, Douglas James

The United States Air Force (USAF) continues to have a need for assured access to space. In addition to flexible and responsive spacelift, a reduction in the cost per launch of space launch vehicles is also desirable. For this purpose, an investigation of the design optimization of space launch vehicles has been conducted. Using a suite of custom codes, the performance aspects of an entire space launch vehicle were analyzed. A genetic algorithm (GA) was employed to optimize the design of the space launch vehicle. A cost model was incorporated into the optimization process with the goal of minimizing the overall vehicle cost. The other goals of the design optimization included obtaining the proper altitude and velocity to achieve a low-Earth orbit. Specific mission parameters that are particular to USAF space endeavors were specified at the start of the design optimization process. Solid propellant motors, liquid fueled rockets, and air-launched systems in various configurations provided the propulsion systems for two, three and four-stage launch vehicles. Mass properties models, an aerodynamics model, and a six-degree-of-freedom (6DOF) flight dynamics simulator were all used to model the system. The results show the feasibility of this method in designing launch vehicles that meet mission requirements. Comparisons to existing real world systems provide the validation for the physical system models. However, the ability to obtain a truly minimized cost was elusive. The cost model uses an industry standard approach, however, validation of this portion of the model was challenging due to the proprietary nature of cost figures and due to the dependence of many existing systems on surplus hardware.

Kineto-dynamic design optimisation for vehicle-specific seat-suspension systems

NASA Astrophysics Data System (ADS)

Shangguan, Wen-Bin; Shui, Yijie; Rakheja, Subhash

2017-11-01

Designs and analyses of seat-suspension systems are invariably performed considering effective vertical spring rate and damping properties, while neglecting important contributions due to kinematics of the widely used cross-linkage mechanism. In this study, a kineto-dynamic model of a seat-suspension is formulated to obtain relations for effective vertical suspension stiffness and damping characteristics as functions of those of the air spring and the hydraulic damper, respectively. The proposed relations are verified through simulations of the multi-body dynamic model of the cross-linkage seat-suspension in the ADAMS platform. The validity of the kineto-dynamic model is also demonstrated through comparisons of its vibration transmission response with the experimental data. The model is used to identify optimal air spring coordinates to attain nearly constant natural frequency of the suspension, irrespective of the seated body mass and seated height. A methodology is further proposed to identify optimal damping requirements for vehicle-specific suspension designs to achieve minimal seat effective amplitude transmissibility (SEAT) and vibration dose value (VDV) considering vibration spectra of different classes of earthmoving vehicles. The shock and vibration isolation performance potentials of the optimal designs are evaluated under selected vehicle vibration superimposed with shock motions. Results show that the vehicle-specific optimal designs could provide substantial reductions in the SEAT and VDV values for the vehicle classes considered.

HIFiRE-5 Flight Vehicle Design

NASA Technical Reports Server (NTRS)

Kimmel, Roger L.; Adamczak, David; Berger, Karen; Choudhari, Meelan

2010-01-01

The Hypersonic International Flight Research Experimentation (HIFiRE) program is a hypersonic flight test program executed by the Air Force Research Laboratories (AFRL) and Australian Defence Science and Technology Organization (DSTO). HIFiRE flight 5 is devoted to measuring transition on a three-dimensional body. This paper summarizes payload configuration, trajectory, vehicle stability limits and roughness tolerances. Results show that the proposed configuration is suitable for testing transition on a three-dimensional body. Transition is predicted to occur within the test window, and a design has been developed that will allow the vehicle to be manufactured within prescribed roughness tolerances

Modeling Languages Refine Vehicle Design

NASA Technical Reports Server (NTRS)

2009-01-01

Cincinnati, Ohio s TechnoSoft Inc. is a leading provider of object-oriented modeling and simulation technology used for commercial and defense applications. With funding from Small Business Innovation Research (SBIR) contracts issued by Langley Research Center, the company continued development on its adaptive modeling language, or AML, originally created for the U.S. Air Force. TechnoSoft then created what is now known as its Integrated Design and Engineering Analysis Environment, or IDEA, which can be used to design a variety of vehicles and machinery. IDEA's customers include clients in green industries, such as designers for power plant exhaust filtration systems and wind turbines.

Effect of Intake Air Filter Condition on Vehicle Fuel Economy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Norman, Kevin M; Huff, Shean P; West, Brian H

2009-02-01

decrease in fuel economy with increasing restriction. However, the level of restriction required to cause a substantial (10-15%) decrease in fuel economy (such as that cited in the literature) was so severe that the vehicle was almost undrivable. Acceleration performance on all vehicles was improved with a clean air filter. Once it was determined how severe the restriction had to be to affect the carbureted vehicle fuel economy, the 2007 Buick Lucerne was retested in a similar manner. We were not able to achieve the level of restriction that was achieved with the 1972 Pontiac with the Lucerne. The Lucerne's air filter box would not hold the filter in place under such severe conditions. (It is believed that this testing exceeded the design limits of the air box.) Tests were conducted at a lower restriction level (although still considerably more severe than the initial clogged filter testing), allowing the air filter to stay seated in the air box, and no significant change was observed in the Lucerne's fuel economy or the AFR over the HFET cycle. Closed-loop control in modern fuel injected vehicle applications is sophisticated enough to keep a clogged air filter from affecting the vehicle fuel economy. However for older, open-loop, carbureted vehicles, a clogged air filter can affect the fuel economy. For the vehicle tested, the fuel economy with a new air filter improved as much as 14% over that with a severely clogged filter (in which the filter was so clogged that drivability was impacted). Under a more typical state of clog, the improvement with a new filter ranged from 2 to 6%.« less

Robust Adaptive Flight Control Design of Air-breathing Hypersonic Vehicles

DTIC Science & Technology

2016-12-07

dynamic inversion controller design for a non -minimum phase hypersonic vehicle is derived by Kuipers et al. [2008]. Moreover, integrated guidance and...stabilization time for inner loop variables is lesser than the intermediate loop variables because of the three-loop-control design methodology . The control...adaptive design . Control Engineering Practice, 2016. Michael A Bolender and David B Doman. A non -linear model for the longitudinal dynamics of a

Detail design of empennage of an unmanned aerial vehicle

NASA Astrophysics Data System (ADS)

Sarker, Md. Samad; Panday, Shoyon; Rasel, Md; Salam, Md. Abdus; Faisal, Kh. Md.; Farabi, Tanzimul Hasan

2017-12-01

In order to maintain the operational continuity of air defense systems, unmanned autonomous or remotely controlled unmanned aerial vehicle (UAV) plays a great role as a target for the anti-aircraft weapons. The aerial vehicle must comply with the requirements of high speed, remotely controlled tracking and navigational aids, operational sustainability and sufficient loiter time. It can also be used for aerial reconnaissance, ground surveillance and other intelligence operations. This paper aims to develop a complete tail design of an unmanned aerial vehicle using Systems Engineering approach. The design fulfils the requirements of longitudinal and directional trim, stability and control provided by the horizontal and vertical tail. Tail control surfaces are designed to provide sufficient control of the aircraft in critical conditions. Design parameters obtained from wing design are utilized in the tail design process as required. Through chronological calculations and successive iterations, optimum values of 26 tail design parameters are determined.

A Summary of the NASA Design Environment for Novel Vertical Lift Vehicles (DELIVER) Project

NASA Technical Reports Server (NTRS)

Theodore, Colin R.

2018-01-01

The number of new markets and use cases being developed for vertical take-off and landing vehicles continues to explode, including the highly publicized urban air taxi and package deliver applications. There is an equally exploding variety of novel vehicle configurations and sizes that are being proposed to fill these new market applications. The challenge for vehicle designers is that there is currently no easy and consistent way to go from a compelling mission or use case to a vehicle that is best configured and sized for the particular mission. This is because the availability of accurate and validated conceptual design tools for these novel types and sizes of vehicles have not kept pace with the new markets and vehicles themselves. The Design Environment for Novel Vertical Lift Vehicles (DELIVER) project was formulated to address this vehicle design challenge by demonstrating the use of current conceptual design tools, that have been used for decades to design and size conventional rotorcraft, applied to these novel vehicle types, configurations and sizes. In addition to demonstrating the applicability of current design and sizing tools to novel vehicle configurations and sizes, DELIVER also demonstrated the addition of key transformational technologies of noise, autonomy, and hybrid-electric and all-electric propulsion into the vehicle conceptual design process. Noise is key for community acceptance, autonomy and the need to operate autonomously are key for efficient, reliable and safe operations, and electrification of the propulsion system is a key enabler for these new vehicle types and sizes. This paper provides a summary of the DELIVER project and shows the applicability of current conceptual design and sizing tools novel vehicle configurations and sizes that are being proposed for urban air taxi and package delivery type applications.

Wind and water tunnel testing of a morphing aquatic micro air vehicle.

PubMed

Siddall, Robert; Ortega Ancel, Alejandro; Kovač, Mirko

2017-02-06

Aerial robots capable of locomotion in both air and water would enable novel mission profiles in complex environments, such as water sampling after floods or underwater structural inspections. The design of such a vehicle is challenging because it implies significant propulsive and structural design trade-offs for operation in both fluids. In this paper, we present a unique Aquatic Micro Air Vehicle (AquaMAV), which uses a reconfigurable wing to dive into the water from flight, inspired by the plunge diving strategy of water diving birds in the family Sulidae . The vehicle's performance is investigated in wind and water tunnel experiments, from which we develop a planar trajectory model. This model is used to predict the dive behaviour of the AquaMAV, and investigate the efficacy of passive dives initiated by wing folding as a means of water entry. The paper also includes first field tests of the AquaMAV prototype where the folding wings are used to initiate a plunge dive.

Wind and water tunnel testing of a morphing aquatic micro air vehicle

PubMed Central

Ortega Ancel, Alejandro; Kovač, Mirko

2017-01-01

Aerial robots capable of locomotion in both air and water would enable novel mission profiles in complex environments, such as water sampling after floods or underwater structural inspections. The design of such a vehicle is challenging because it implies significant propulsive and structural design trade-offs for operation in both fluids. In this paper, we present a unique Aquatic Micro Air Vehicle (AquaMAV), which uses a reconfigurable wing to dive into the water from flight, inspired by the plunge diving strategy of water diving birds in the family Sulidae. The vehicle's performance is investigated in wind and water tunnel experiments, from which we develop a planar trajectory model. This model is used to predict the dive behaviour of the AquaMAV, and investigate the efficacy of passive dives initiated by wing folding as a means of water entry. The paper also includes first field tests of the AquaMAV prototype where the folding wings are used to initiate a plunge dive. PMID:28163877

The promise of air cargo-system aspects and vehicle design

NASA Technical Reports Server (NTRS)

Whitehead, A. H., Jr.

1977-01-01

A review of the current operation of the air cargo system is presented and the prospects for the future are discussed. Attention is given to air cargo demand forecasts, the economics of air cargo transport, the development of an integrated air cargo system, and the evolution of airfreighter design. Particular emphasis is placed on the span-distributed load concept, examining the Boeing, Douglas, and Lockheed spanloaders.

The promise of air cargo: System aspects and vehicle design

NASA Technical Reports Server (NTRS)

Whitehead, A. H., Jr.

1976-01-01

The current operation of the air cargo system is reviewed. An assessment of the future of air cargo is provided by: (1) analyzing statistics and trends, (2) by noting system problems and inefficiencies, (3) by analyzing characteristics of 'air eligible' commodities, and (4) by showing the promise of new technology for future cargo aircraft with significant improvements in costs and efficiency. The following topics are discussed: (1) air cargo demand forecasts; (2) economics of air cargo transport; (3) the integrated air cargo system; (4) evolution of airfreighter design; and (5) the span distributed load concept.

PECASE: Soaring Mechanisms for Flapping-Wing Micro Air Vehicles

DTIC Science & Technology

2015-03-31

2015 2. REPORT TYPE Final 4. TITLE AND SUBTITLE PECASE: Soaring mechanisms for flapping - wing micro air vehicles 6. AUTHOR(S) Robert J. Wood 3...N00014-10-1-0684 Award Title: "PECASE: Soaring mechanisms for flapping - wing micro air vehicles" [previous award: N00014-08-1-0919, "Hovering Control for...Insect-Inspired Flapping - Wing Micro Air Vehicles"] Final report a. Scientific and Technical Objectives The Harvard Microrobotics Lab has

Development of Micro Air Reconnaissance Vehicle as a Test Bed for Advanced Sensors and Electronics

NASA Technical Reports Server (NTRS)

Shams, Qamar A.; Vranas, Thomas L.; Fox, Robert L.; Kuhn, Theodore R.; Ingham, John; Logan, Michael J.; Barnes, Kevin N.; Guenther, Benjamin F.

2002-01-01

This paper describes the development of a Micro/Mini Air Reconnaissance Vehicle for advanced sensors and electronics at NASA Langley Research Center over the last year. This vehicle is expected to have a total weight of less than four pounds, a design velocity of 40 mph, an endurance of 15-20 minutes, and a maximum range of 5km. The vehicle has wings that are simple to detach yet retain the correct alignment. The upper fuselage surface has a quick release hatch used to access the interior and also to mount the varying propulsion systems. The sensor suite developed for this vehicle consists of a Pitot-static measurement system for determining air speed, an absolute pressure measurement for determining altitude, magnetic direction measurement, and three orthogonal gyros to determine body angular rates. Swarming GPS-guidance and in-flight maneuvering is discussed, as well as design and installation of some other advance sensors like MEMS microphones, infrared cameras, GPS, humidity sensors, and an ultrasonic sonar sensor. Also low cost, small size, high performance control and navigation system for the Micro Air Vehicle is discussed. At the end, laboratory characterization of different sensors, motors, propellers, and batteries will be discussed.

Impact of aeroelasticity on propulsion and longitudinal flight dynamics of an air-breathing hypersonic vehicle

NASA Technical Reports Server (NTRS)

Raney, David L.; Mcminn, John D.; Pototzky, Anthony S.; Wooley, Christine L.

1993-01-01

Many air-breathing hypersonic aerospacecraft design concepts incorporate an elongated fuselage forebody acting as the aerodynamic compression surface for a hypersonic combustion module, or scram jet. This highly integrated design approach creates the potential for an unprecedented form of aero-propulsive-elastic interaction in which deflections of the vehicle fuselage give rise to propulsion transients, producing force and moment variations that may adversely impact the rigid body flight dynamics and/or further excite the fuselage bending modes. To investigate the potential for such interactions, a math model was developed which included the longitudinal flight dynamics, propulsion system, and first seven elastic modes of a hypersonic air-breathing vehicle. Perturbation time histories from a simulation incorporating this math model are presented that quantify the propulsive force and moment variations resulting from aeroelastic vehicle deflections. Root locus plots are presented to illustrate the effect of feeding the propulsive perturbations back into the aeroelastic model. A concluding section summarizes the implications of the observed effects for highly integrated hypersonic air-breathing vehicle concepts.

Impact of aeroelasticity on propulsion and longitudinal flight dynamics of an air-breathing hypersonic vehicle

NASA Astrophysics Data System (ADS)

Raney, David L.; McMinn, John D.; Pototzky, Anthony S.; Wooley, Christine L.

1993-04-01

Many air-breathing hypersonic aerospacecraft design concepts incorporate an elongated fuselage forebody acting as the aerodynamic compression surface for a hypersonic combustion module, or scram jet. This highly integrated design approach creates the potential for an unprecedented form of aero-propulsive-elastic interaction in which deflections of the vehicle fuselage give rise to propulsion transients, producing force and moment variations that may adversely impact the rigid body flight dynamics and/or further excite the fuselage bending modes. To investigate the potential for such interactions, a math model was developed which included the longitudinal flight dynamics, propulsion system, and first seven elastic modes of a hypersonic air-breathing vehicle. Perturbation time histories from a simulation incorporating this math model are presented that quantify the propulsive force and moment variations resulting from aeroelastic vehicle deflections. Root locus plots are presented to illustrate the effect of feeding the propulsive perturbations back into the aeroelastic model. A concluding section summarizes the implications of the observed effects for highly integrated hypersonic air-breathing vehicle concepts.

Conceptual design of a two-stage-to-orbit vehicle

NASA Technical Reports Server (NTRS)

1991-01-01

A conceptual design study of a two-stage-to-orbit vehicle is presented. Three configurations were initially investigated with one configuration selected for further development. The major objective was to place a 20,000-lb payload into a low Earth orbit using a two-stage vehicle. The first stage used air-breathing engines and employed a horizontal takeoff, while the second stage used rocket engines to achieve a 250-n.m. orbit. A two-stage-to-orbit vehicle seems a viable option for the next-generation space shuttle.

Potential air pollutant emission from private vehicles based on vehicle route

NASA Astrophysics Data System (ADS)

Huboyo, H. S.; Handayani, W.; Samadikun, B. P.

2017-06-01

Air emissions related to the transportation sector has been identified as the second largest emitter of ambient air quality in Indonesia. This is due to large numbers of private vehicles commuting within the city as well as inter-city. A questionnaire survey was conducted in Semarang city involving 711 private vehicles consisting of cars and motorcycles. The survey was conducted in random parking lots across the Semarang districts and in vehicle workshops. Based on the parking lot survey, the average distance private cars travelled in kilometers (VKT) was 17,737 km/year. The machine start-up number of cars during weekdays; weekends were on average 5.19 and 3.79 respectively. For motorcycles the average of kilometers travelled was 27,092 km/year. The machine start-up number of motorcycles during weekdays and weekends were on average 5.84 and 3.98, respectively. The vehicle workshop survey showed the average kilometers travelled to be 9,510 km/year for motorcycles, while for private cars the average kilometers travelled was 21,347 km/year. Odometer readings for private cars showed a maximum of 3,046,509 km and a minimum of 700 km. Meanwhile, for motorcycles, odometer readings showed a maximum of 973,164 km and a minimum of roughly 54.24 km. Air pollutant emissions on East-West routes were generally higher than those on South-North routes. Motorcycles contribute significantly to urban air pollution, more so than cars. In this study, traffic congestion and traffic volume contributed much more to air pollution than the impact of fluctuating terrain.

Principles of Air Defense and Air Vehicle Penetration

DTIC Science & Technology

2000-03-01

Range For reliable dateetien, the target signal must reach some minimum or threshold value called S . . When internal noise is the only interfer...analyze air defense and air vehicle penetration. Unique expected value models are developed with frequent numerical examples. Radar...penetrator in the presence of spurious returns from internal and external noise will be discussed. Tracking With sufficient sensor information to determine

Design of elevator control surface actuated by LIPCA for small unmanned air vehicle

NASA Astrophysics Data System (ADS)

Yoon, K. J.; Setiawan, Hery; Goo, N. S.

2006-03-01

There have been persistent interests in high performance actuators suitable for the actuation of control surfaces of small aircraft and helicopter blades and for active vibration control of aerospace and submarine structures that need high specific force and displacement. What is really needed for active actuation is a large-displacement actuator with a compact source, i.e., much higher strain. A lot of effort has been made to develop compact actuators with large displacement at a high force. One of the representative actuator is LIPCA actuator that was introduced by Yoon et al. The LIPCA design offers the advantages to be applied as actuator for the small aerial vehicle comparing with any other actuators. The weight is one of the main concerns for aerospace field, and since LIPCA has lighter weight than any other piezo-actuator thus it is suitable as actuator for small aircraft control surface. In this paper, a conceptual design of LIPCA-actuated control surface is introduced. A finite element model was constructed and analyzed to predict the deflection angle of the control surface. The hinge moment that produced by the aerodynamic forces was calculated to determine the optimum position of the hinge point, which could produce the deflection as high as possible with reasonable hinge moment. To verify the prediction, a prototype of SUAV (small unmanned air vehicle) control surface was manufactured and tested both in static condition and in the wind tunnel. The prediction and test results showed a good agreement on the control surface deflection angle.

Novel adaptive neural control design for a constrained flexible air-breathing hypersonic vehicle based on actuator compensation

NASA Astrophysics Data System (ADS)

Bu, Xiangwei; Wu, Xiaoyan; He, Guangjun; Huang, Jiaqi

2016-03-01

This paper investigates the design of a novel adaptive neural controller for the longitudinal dynamics of a flexible air-breathing hypersonic vehicle with control input constraints. To reduce the complexity of controller design, the vehicle dynamics is decomposed into the velocity subsystem and the altitude subsystem, respectively. For each subsystem, only one neural network is utilized to approach the lumped unknown function. By employing a minimal-learning parameter method to estimate the norm of ideal weight vectors rather than their elements, there are only two adaptive parameters required for neural approximation. Thus, the computational burden is lower than the ones derived from neural back-stepping schemes. Specially, to deal with the control input constraints, additional systems are exploited to compensate the actuators. Lyapunov synthesis proves that all the closed-loop signals involved are uniformly ultimately bounded. Finally, simulation results show that the adopted compensation scheme can tackle actuator constraint effectively and moreover velocity and altitude can stably track their reference trajectories even when the physical limitations on control inputs are in effect.

Configuration Studies of Personal Air Vehicles. Personal Air Vehicle and Flying Jeep Concepts: A Commentary on Promising Approaches or What Goes Around Comes Around (About Every Twenty Years)

NASA Technical Reports Server (NTRS)

Hall, David W.

2001-01-01

The NASA/Langley Personal Air Vehicle (PAV) Exploration (PAVE) and the DARPA (Defense Advanced Research Projects Agency) Dual Air/Road Transportation System (DARTS) projects were established to investigate the feasibility of creating vehicles which could replace, or at the very least augment, personal ground and air transportation schemes. This overall goal implies integrating several technology areas with practical everyday transportation requirements to design a class of vehicles which will achieve the following goals: (1) Vertical, Extremely Short, or Short Takeoff and Landing (VTOL, ESTOL, STOL) capability; (2) Operation at block speeds markedly faster than current combinations of land and air transportation, particularly in critical market areas; (3) Unit cost comparable to current luxury cars and small general aviation aircraft; (4) Excellent reliability; (5) Excellent safety; (6) Ability to integrate with existing land and air transportation systems. The conclusions of these configuration studies are summarized as follows: (1) Creation of the five assigned configurations prompted added explorations, some of which were dead-ends; (2) Some components could be common to all configurations such as avionics and dual-mode suspension schemes; (3) Single-Mode PAVs can be created by removing dual-mode-specific items; (4) Aviation history provided some intriguing starting points, as in what goes around comes around; (5) CTOL (Conventional Take-off and Landing) and STOL dual-mode PAVs look feasible with single-mode PAVs being simplifications of the dual-mode approach; (6) VTOL PAVs will require development; (7) More exotic collapsing mechanisms mechanisms need development; (8) As a teaching tool, PAVs are not yet a well-enough bounded design problem.

Measurement of Vehicle Air Conditioning Pull-Down Period

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, John F.; Huff, Shean P.; Moore, Larry G.

2016-08-01

Air conditioner usage was characterized for high heat-load summer conditions during short driving trips using a 2009 Ford Explorer and a 2009 Toyota Corolla. Vehicles were parked in the sun with windows closed to allow the cabin to become hot. Experiments were conducted by entering the instrumented vehicles in this heated condition and driving on-road with the windows up and the air conditioning set to maximum cooling, maximum fan speed and the air flow setting to recirculate cabin air rather than pull in outside humid air. The main purpose was to determine the length of time the air conditioner systemmore » would remain at or very near maximum cooling power under these severe-duty conditions. Because of the variable and somewhat uncontrolled nature of the experiments, they serve only to show that for short vehicle trips, air conditioning can remain near or at full cooling capacity for 10-minutes or significantly longer and the cabin may be uncomfortably warm during much of this time.« less

A Fixed-Wing Micro Air Vehicle with Hovering Capability

DTIC Science & Technology

2010-12-01

AFRL-AFOSR-UK-TR-2010-0001 A Fixed-Wing Micro Air Vehicle with Hovering Capability Jean-Marc Moschetta SUPAERO Dept of...06 July 2010 Air Force Research Laboratory Air Force Office of Scientific Research European Office of Aerospace Research and...To) 06 July 2007 - 06 July 2010 4. TITLE AND SUBTITLE A Fixed-Wing Micro Air Vehicle with Hovering Capability 5a. CONTRACT NUMBER FA8655-07

Measuring concentrations of selected air pollutants inside California vehicles. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodes, C.; Sheldon, L.; Whitaker, D.

1999-01-01

This project measured 2-hour integrated concentrations of PM10, PM2.5, metals and a number of organic chemicals including benzene and MTBE inside vehicles on California roadways. Using continuous samplers, particle counts, black carbon, and CO were also measured. In addition to measuring in-vehicle levels, the investigators measured pollutant levels just outside the vehicle, at roadside stations, and ambient air monitoring stations. Different driving scenarios were designed to assess the effects of a number of factors on in-vehicle pollutant levels. These factors included roadway type, carpool lanes, traffic conditions, geographical locations, vehicle type, and vehicle ventilation conditions. The statewide average in-vehicle concentrationsmore » of benzene, MTBE, and formaldehyde ranged from 3--22 {micro}g/m{sup 3}, 3--90 {micro}g/m{sup 3}, and 0---22 {micro}g/m{sup 3}, respectively. The ranges of mean PM10 and PM2.5 in-vehicle levels in Sacramento were 20--40 {micro}g/m{sup 3} and 6--22 {micro}g/m{sup 3}, respectively. In general, pollutant levels inside or just outside the vehicles were higher than those measured at the roadside stations or the ambient air stations. In-vehicle pollutant levels were consistently higher in Los Angeles than Sacramento. Pollutant levels measured inside vehicles traveling in a carpool lane were much lower than those in the right-hand, slower lanes. Under the study conditions, factors such as vehicle type and ventilation and little effect on in-vehicle pollutant levels. Other factors, such as roadway type, freeway congestion level, and time-of-day had some influence on in-vehicle pollution levels.« less

Water facilities in retrospect and prospect: An illuminating tool for vehicle design

NASA Technical Reports Server (NTRS)

Erickson, G. E.; Peak, D. J.; Delfrate, J.; Skow, A. M.; Malcolm, G. N.

1986-01-01

Water facilities play a fundamental role in the design of air, ground, and marine vehicles by providing a qualitative, and sometimes quantitative, description of complex flow phenomena. Water tunnels, channels, and tow tanks used as flow-diagnostic tools have experienced a renaissance in recent years in response to the increased complexity of designs suitable for advanced technology vehicles. These vehicles are frequently characterized by large regions of steady and unsteady three-dimensional flow separation and ensuing vortical flows. The visualization and interpretation of the complicated fluid motions about isolated vehicle components and complete configurations in a time and cost effective manner in hydrodynamic test facilities is a key element in the development of flow control concepts, and, hence, improved vehicle designs. A historical perspective of the role of water facilities in the vehicle design process is presented. The application of water facilities to specific aerodynamic and hydrodynamic flow problems is discussed, and the strengths and limitations of these important experimental tools are emphasized.

The Sensitivity of Precooled Air-Breathing Engine Performance to Heat Exchanger Design Parameters

NASA Astrophysics Data System (ADS)

Webber, H.; Bond, A.; Hempsell, M.

The issues relevant to propulsion design for Single Stage To Orbit (SSTO) vehicles are considered. In particular two air- breathing engine concepts involving precooling are compared; SABRE (Synergetic Air-Breathing and Rocket Engine) as designed for the Skylon SSTO launch vehicle, and a LACE (Liquid Air Cycle Engine) considered in the 1960's by the Americans for an early generation spaceplane. It is shown that through entropy minimisation the SABRE has made substantial gains in performance over the traditional LACE precooled engine concept, and has shown itself as the basis of a viable means of realising a SSTO vehicle. Further, it is demonstrated that the precooler is a major source of thermodynamic irreversibility within the engine cycle and that further reduction in entropy can be realised by increasing the heat transfer coefficient on the air side of the precooler. If this were to be achieved, it would improve the payload mass delivered to orbit by the Skylon launch vehicle by between 5 and 10%.

78 FR 29815 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-21

...This action would establish more stringent vehicle emissions standards and reduce the sulfur content of gasoline beginning in 2017, as part of a systems approach to addressing the impacts of motor vehicles and fuels on air quality and public health. The proposed gasoline sulfur standard would make emission control systems more effective for both existing and new vehicles, and would enable more stringent vehicle emissions standards. The proposed vehicle standards would reduce both tailpipe and evaporative emissions from passenger cars, light-duty trucks, medium-duty passenger vehicles, and some heavy-duty vehicles. This would result in significant reductions in pollutants such as ozone, particulate matter, and air toxics across the country and help state and local agencies in their efforts to attain and maintain health-based National Ambient Air Quality Standards. Motor vehicles are an important source of exposure to air pollution both regionally and near roads. These proposed vehicle standards are intended to harmonize with California's Low Emission Vehicle program, thus creating a federal vehicle emissions program that would allow automakers to sell the same vehicles in all 50 states. The proposed vehicle standards would be implemented over the same timeframe as the greenhouse gas/fuel efficiency standards for light-duty vehicles, as part of a comprehensive approach toward regulating emissions from motor vehicles.

Aluminum Rich Epoxy Primer for Ground and Air Vehicles

DTIC Science & Technology

2017-03-01

UNCLASSIFIED DOCUMENT Aluminum Rich Epoxy Primer for Ground and Air Vehicles Monthly Technical Report for the Period: January 20, 2017...Objective: To further develop the Aluminum Rich Epoxy Primer systems for Air and Ground Vehicles while addressing the objective requirements

Control and trajectory design of a highly flexible air vehicle with a distributed sensing architecture

NASA Astrophysics Data System (ADS)

Pachikara, Abraham James

Next generational aircraft are becoming very flexible due to efforts to reduce weight and increase aerodynamic efficiency. As a result, flight control systems and trajectories that were designed with traditional rigid body assumptions may no longer become valid. When an aircraft becomes more flexible, the shape of the aircraft can deform significantly due to the aeroservoelastic dynamics. No longer are few sensors located at the CG and elsewhere will be enough to maximize performance. Instead, a full suite of sensors will be needed all throughout the aircraft to accurately measure the complete aerodynamic distribution and dynamics. First, a parametric study will be conducted to understand how flexibility impacts both the open-loop and closed-loop dynamics of a generic micro air vehicle (MAV). Once the impact of flexibility on the MAV's aeroservoelastic dynamics is well understood, an aeroservoelastic flight controller will be designed that leverages a "Fly-By-Feel" sensor architecture. A sensor architecture will be developed that uses several sensors to estimate the MAV's full aerodynamic and inertial distribution along with inertial sensors at the CG. A modal filtering approach will be used for the relevant sensor management and to extract useful modal characteristics from the sensor data. Once that is done, a controller will be designed for maneuver tracking. Once a flight controller has been designed, a set of representative motion primitives for the MAV can be developed that model how the aircraft moves for trajectory generation. Then trajectories can be developed for the flexible vehicle. Analysis will then be conducted to understand how flexibility impacts the creation of trajectories and MAV performance metrics.

Air to air views of Endeavour, Orbiter Vehicle (OV) 105

NASA Image and Video Library

1959-01-01

Air to air views of Endeavour, Orbiter Vehicle (OV) 105, transported via the Shuttle Carrier Aircraft (SCA), NASA 911, on its way to KSC, 05-06-91. JSC with Clear Creek and Egret Bay Blvd in the foreground and Clear Lake and Galveston Bay in the background

Pitching stability analysis of half-rotating wing air vehicle

NASA Astrophysics Data System (ADS)

Wang, Xiaoyi; Wu, Yang; Li, Qian; Li, Congmin; Qiu, Zhizhen

2017-06-01

Half-Rotating Wing (HRW) is a new power wing which had been developed by our work team using rotating-type flapping instead of oscillating-type flapping. Half-Rotating Wing Air Vehicle (HRWAV) is similar as Bionic Flapping Wing Air Vehicle (BFWAV). It is necessary to guarantee pitching stability of HRWAV to maintain flight stability. The working principle of HRW was firstly introduced in this paper. The rule of motion indicated that the fuselage of HRWAV without empennage would overturn forward as it generated increased pitching movement. Therefore, the empennage was added on the tail of HRWAV to balance the additional moment generated by aerodynamic force during flight. The stability analysis further shows that empennage could weaken rapidly the pitching disturbance on HRWAV and a new balance of fuselage could be achieved in a short time. Case study using numerical analysis verified correctness and validity of research results mentioned above, which could provide theoretical guidance to design and control HRWAV.

Design and development of flapping wing micro air vehicle

NASA Astrophysics Data System (ADS)

Hynes, N. Rajesh Jesudoss; Solomon, A. Jeffey Markus; Kathiresh, E.; Brighton, D.; Velu, P. Shenbaga

2018-05-01

Birds and insects have different methods of producing lift and thrust for hovering and forward flight. Most birds, however, cannot hover. Wing tips of birds follow simple paths in flight, whereas insects have very complicated wing tip paths, for hovering and forward flight, which vary with each species. FMAV based on avian flight. Development of Flapping Wing Air Vehicle (FWAV) is an on-going quest to master the natural flyers by mechanical means. It is characterized by unsteady aerodynamics, whose knowledge is still developing. The present work aims at include being capable of manoeuvring around and over obstacles by adjusting pitch, yaw, and roll, able to glide for five seconds under its own power, skilful at alternating between flapping and gliding with minimal disruption of flight pattern and being durable enough to withstand impacts with minimal to no damage.

Comprehensive modeling and control of flexible flapping wing micro air vehicles

NASA Astrophysics Data System (ADS)

Nogar, Stephen Michael

Flapping wing micro air vehicles hold significant promise due to the potential for improved aerodynamic efficiency, enhanced maneuverability and hover capability compared to fixed and rotary configurations. However, significant technical challenges exist to due the lightweight, highly integrated nature of the vehicle and coupling between the actuators, flexible wings and control system. Experimental and high fidelity analysis has demonstrated that aeroelastic effects can change the effective kinematics of the wing, reducing vehicle stability. However, many control studies for flapping wing vehicles do not consider these effects, and instead validate the control strategy with simple assumptions, including rigid wings, quasi-steady aerodynamics and no consideration of actuator dynamics. A control evaluation model that includes aeroelastic effects and actuator dynamics is developed. The structural model accounts for geometrically nonlinear behavior using an implicit condensation technique and the aerodynamic loads are found using a time accurate approach that includes quasi-steady, rotational, added mass and unsteady effects. Empirically based parameters in the model are fit using data obtained from a higher fidelity solver. The aeroelastic model and its ingredients are compared to experiments and computations using models of higher fidelity, and indicate reasonable agreement. The developed control evaluation model is implemented in a previously published, baseline controller that maintains stability using an asymmetric wingbeat, known as split-cycle, along with changing the flapping frequency and wing bias. The model-based controller determines the control inputs using a cycle-averaged, linear control design model, which assumes a rigid wing and no actuator dynamics. The introduction of unaccounted for dynamics significantly degrades the ability of the controller to track a reference trajectory, and in some cases destabilizes the vehicle. This demonstrates the

Missions and vehicle concepts for modern, propelled, lighter-than-air vehicles

NASA Technical Reports Server (NTRS)

Ardema, M. D.

1984-01-01

The results of studies conducted over the last 15 years to assess missions and vehicle concepts for modern, propelled, lighter-than-air vehicles (airships) were surveyed. Rigid and non-rigid airship concepts are considered. The use of airships for ocean patrol and surveillance is discussed along with vertical heavy lift airships. Military and civilian needs for high altitude platforms are addressed.

CFD based aerodynamic modeling to study flight dynamics of a flapping wing micro air vehicle

NASA Astrophysics Data System (ADS)

Rege, Alok Ashok

The demand for small unmanned air vehicles, commonly termed micro air vehicles or MAV's, is rapidly increasing. Driven by applications ranging from civil search-and-rescue missions to military surveillance missions, there is a rising level of interest and investment in better vehicle designs, and miniaturized components are enabling many rapid advances. The need to better understand fundamental aspects of flight for small vehicles has spawned a surge in high quality research in the area of micro air vehicles. These aircraft have a set of constraints which are, in many ways, considerably different from that of traditional aircraft and are often best addressed by a multidisciplinary approach. Fast-response non-linear controls, nano-structures, integrated propulsion and lift mechanisms, highly flexible structures, and low Reynolds aerodynamics are just a few of the important considerations which may be combined in the execution of MAV research. The main objective of this thesis is to derive a consistent nonlinear dynamic model to study the flight dynamics of micro air vehicles with a reasonably accurate representation of aerodynamic forces and moments. The research is divided into two sections. In the first section, derivation of the nonlinear dynamics of flapping wing micro air vehicles is presented. The flapping wing micro air vehicle (MAV) used in this research is modeled as a system of three rigid bodies: a body and two wings. The design is based on an insect called Drosophila Melanogaster, commonly known as fruit-fly. The mass and inertial effects of the wing on the body are neglected for the present work. The nonlinear dynamics is simulated with the aerodynamic data published in the open literature. The flapping frequency is used as the control input. Simulations are run for different cases of wing positions and the chosen parameters are studied for boundedness. Results show a qualitative inconsistency in boundedness for some cases, and demand a better

75 FR 15620 - Federal Motor Vehicle Safety Standards; Air Brake Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-30

... fully develop improved brake systems and also to ensure vehicle control and stability while braking... [Docket No. NHTSA 2009-0175] RIN 2127-AK62 Federal Motor Vehicle Safety Standards; Air Brake Systems... Federal motor vehicle safety standard for air brake systems by requiring substantial improvements in...

78 FR 32223 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-29

...-OAR-2011-0135; FRL-9818-5] RIN 2060-A0 Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards AGENCY: Environmental Protection Agency (EPA). ACTION: Notice... extension of the public comment period for the proposed rule ``Control of Air Pollution from Motor Vehicles...

The design of two stage to orbit vehicles

NASA Astrophysics Data System (ADS)

Gregorek, G. M.; Ramsay, T. N.

1991-09-01

Two designs are presented for a two-stage-to-orbit vehicle to complement an existing heavy lift vehicle. The payload is 10,000 lbs and 27 ft long by 10 ft in diameter for design purposes and must be carried to a low earth orbit by an air-breathing carrier configuration that can take off horizontally within 15,000 ft. Two designs are presented: a delta wing/body carrier in which the fuselage contains the orbiter; and a cranked-delta wing/body carrier in which the orbiter is carried piggy back. The engines for both carriers are turbofanramjets powered with liquid hydrogen, and the orbiters employ either a Space Shuttle Main Engine or a half-scale version with additional scramjet engines. The orbiter based on a full-scale Space Shuttle Main Engine is found to have a significantly higher takeoff weight which results in a higher total takeoff weight.

78 FR 9623 - Federal Motor Vehicle Safety Standards; Air Brake Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-11

... [Docket No. NHTSA-2013-0011] RIN 2127-AL11 Federal Motor Vehicle Safety Standards; Air Brake Systems... rule that amended the Federal motor vehicle safety standard for air brake systems by requiring... published a final rule in the Federal Register amending Federal Motor Vehicle Safety Standard (FMVSS) No...

76 FR 44829 - Federal Motor Vehicle Safety Standards; Air Brake Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-27

... [Docket No. NHTSA-2009-0175] RIN 2127-AK84 Federal Motor Vehicle Safety Standards; Air Brake Systems... final rule that amended the Federal motor vehicle safety standard for air brake systems by requiring... July 27, 2009, NHTSA published a final rule in the Federal Register amending Federal Motor Vehicle...

High specific energy and specific power aluminum/air battery for micro air vehicles

NASA Astrophysics Data System (ADS)

Kindler, A.; Matthies, L.

2014-06-01

Micro air vehicles developed under the Army's Micro Autonomous Systems and Technology program generally need a specific energy of 300 - 550 watt-hrs/kg and 300 -550 watts/kg to operate for about 1 hour. At present, no commercial cell can fulfill this need. The best available commercial technology is the Lithium-ion battery or its derivative, the Li- Polymer cell. This chemistry generally provides around 15 minutes flying time. One alternative to the State-of-the Art is the Al/air cell, a primary battery that is actually half fuel cell. It has a high energy battery like aluminum anode, and fuel cell like air electrode that can extract oxygen out of the ambient air rather than carrying it. Both of these features tend to contribute to a high specific energy (watt-hrs/kg). High specific power (watts/kg) is supported by high concentration KOH electrolyte, a high quality commercial air electrode, and forced air convection from the vehicles rotors. The performance of this cell with these attributes is projected to be 500 watt-hrs/kg and 500 watts/kg based on simple model. It is expected to support a flying time of approximately 1 hour in any vehicle in which the usual limit is 15 minutes.

In-Cabin Air Quality during Driving and Engine Idling in Air-Conditioned Private Vehicles in Hong Kong.

PubMed

Barnes, Natasha Maria; Ng, Tsz Wai; Ma, Kwok Keung; Lai, Ka Man

2018-03-27

Many people spend lengthy periods each day in enclosed vehicles in Hong Kong. However, comparably limited data is available about in-cabin air quality in air-conditioned private vehicles, and the car usage that may affect the air quality. Fifty-one vehicles were tested for particulate matter (PM 0.3 and PM 2.5 ), total volatile organic compounds (TVOCs), carbon monoxide (CO), carbon dioxide (CO₂), airborne bacteria, and fungi levels during their routine travel journey. Ten of these vehicles were further examined for PM 0.3 , PM 2.5 , TVOCs, CO, and CO₂ during engine idling. In general, during driving PM 2.5 levels in-cabin reduced overtime, but not PM 0.3 . For TVOCs, 24% vehicles exceeded the recommended Indoor Air Quality (IAQ) level in offices and public places set by the Hong Kong Environmental Protection Department. The total volatile organic compounds (TVOC) concentration positively correlated with the age of the vehicle. Carbon monoxide (CO) levels in all of the vehicles were lower than the IAQ recommendation, while 96% vehicles exceeded the recommended CO₂ level of 1000 ppmv; 16% vehicles >5000 ppmv. Microbial counts were relatively low. TVOCs levels at idle engine were higher than that during driving. Although the time we spend in vehicles is short, the potential exposure to high levels of pollutants should not be overlooked.

In-Cabin Air Quality during Driving and Engine Idling in Air-Conditioned Private Vehicles in Hong Kong

PubMed Central

Barnes, Natasha Maria; Ng, Tsz Wai; Ma, Kwok Keung; Lai, Ka Man

2018-01-01

Many people spend lengthy periods each day in enclosed vehicles in Hong Kong. However, comparably limited data is available about in-cabin air quality in air-conditioned private vehicles, and the car usage that may affect the air quality. Fifty-one vehicles were tested for particulate matter (PM0.3 and PM2.5), total volatile organic compounds (TVOCs), carbon monoxide (CO), carbon dioxide (CO2), airborne bacteria, and fungi levels during their routine travel journey. Ten of these vehicles were further examined for PM0.3, PM2.5, TVOCs, CO, and CO2 during engine idling. In general, during driving PM2.5 levels in-cabin reduced overtime, but not PM0.3. For TVOCs, 24% vehicles exceeded the recommended Indoor Air Quality (IAQ) level in offices and public places set by the Hong Kong Environmental Protection Department. The total volatile organic compounds (TVOC) concentration positively correlated with the age of the vehicle. Carbon monoxide (CO) levels in all of the vehicles were lower than the IAQ recommendation, while 96% vehicles exceeded the recommended CO2 level of 1000 ppmv; 16% vehicles >5000 ppmv. Microbial counts were relatively low. TVOCs levels at idle engine were higher than that during driving. Although the time we spend in vehicles is short, the potential exposure to high levels of pollutants should not be overlooked. PMID:29584686

Design and mechanical analysis of a 3D-printed biodegradable biomimetic micro air vehicle wing

NASA Astrophysics Data System (ADS)

Salami, E.; Ganesan, P. B.; Ward, T. A.; Viyapuri, R.; Romli, F. I.

2016-10-01

The biomimetic micro air vehicles (BMAV) are unmanned, micro-scaled aircraft that are bio-inspired from flying organisms to achieve the lift and thrust by flapping their wings. There are still many technological challenges involved with designing the BMAV. One of these is designing the ultra-lightweight materials and structures for the wings that have enough mechanical strength to withstand continuous flapping at high frequencies. Insects achieve this by having chitin-based, wing frame structures that encompass a thin, film membrane. The main objectives of this study are to design a biodegradable BMAV wing (inspired from the dragonfly) and analyze its mechanical properties. The dragonfly-like wing frame structure was bio-mimicked and fabricated using a 3D printer. A chitosan nanocomposite film membrane was applied to the BMAV wing frames through casting method. Its mechanical performance was analyzed using universal testing machine (UTM). This analysis indicates that the tensile strength and Young's modulus of the wing with a membrane is nearly double that of the wing without a membrane, which allow higher wing beat frequencies and deflections that in turn enable a greater lifting performance.

Environmental Assessment, Balloon Launch and Landing Operations, Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico

DTIC Science & Technology

2012-06-01

Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental Assessment (EA) for...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL /RV) located at Kirtland Air Force Base is preparing an Environmental...United States Air Force Research Laboratory , Space Vehicles Directorate ( AFRL

Tracking control of air-breathing hypersonic vehicles with non-affine dynamics via improved neural back-stepping design.

PubMed

Bu, Xiangwei; He, Guangjun; Wang, Ke

2018-04-01

This study considers the design of a new back-stepping control approach for air-breathing hypersonic vehicle (AHV) non-affine models via neural approximation. The AHV's non-affine dynamics is decomposed into velocity subsystem and altitude subsystem to be controlled separately, and robust adaptive tracking control laws are developed using improved back-stepping designs. Neural networks are applied to estimate the unknown non-affine dynamics, which guarantees the addressed controllers with satisfactory robustness against uncertainties. In comparison with the existing control methodologies, the special contributions are that the non-affine issue is handled by constructing two low-pass filters based on model transformations, and virtual controllers are treated as intermediate variables such that they aren't needed for back-stepping designs any more. Lyapunov techniques are employed to show the uniformly ultimately boundedness of all closed-loop signals. Finally, simulation results are presented to verify the tracking performance and superiorities of the investigated control strategy. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Interagency Workshop on Lighter than Air Vehicles, Monterey, Calif., September 9-13, 1974, Proceedings

NASA Technical Reports Server (NTRS)

Vittek, J. F., Jr.

1975-01-01

Papers are presented which review modern lighter-than-air (LTA) airship design concepts and LTA structures and materials technology, as well as perform economic and market analyses for assessment of the viability of future LTA development programs. Potential applications of LTA vehicles are examined. Some of the topics covered include preliminary estimates of operating costs for LTA transports, an economic comparison of three heavy lift airborn systems, boundary layer control for airships, computer aided flexible envelope designs, state-of-the-art of metalclad airships, aspects of hybrid-Zeppelins, the LTA vehicle as a total cargo system, unmanned powered balloons, and a practical concept for powered or tethered weight-lifting LTA vehicles. Individual items are announced in this issue.

Correlation Analysis between Motor Vehicle Types and Air Pollution in Shijiazhuang City

NASA Astrophysics Data System (ADS)

Pan, Wei-Yi; Shen, Hong-Yan

2018-05-01

Air pollution is more serious than before in Shijiazhuang in recent years, motor vehicle exhaust emissions is one of the major causes of air pollution. The economy is developing rapidly in Shijiazhuang, the motor vehicles increase at a rate of 20% per year. In August 2017, the number of motor vehicles exceeded 2.6 million in Shijiazhuang. In order to explore the relationship between the types of motor vehicles and air pollution in Shijiazhuang. This paper chose the traffic information of the typical roads which are Heping East Road and Yuhua East Road, and determined emission factors, such as CO, HC, NOx, PM10 and so on. The EDMS model was used to calculate the air pollutant discharge emissions inventory and compared with the traffic information. The conclusion is that small cars account for 85% of the total traffic volume, the vehicle exhaust account for 68% of CO, 74% of HC, 77% of NOx and 77% of PM10. Air pollution and the number of small cars have a great correlation. The pollutants contributed by motor vehicles mainly for the small car discharge, in order to reduce the air pollution, relevant departments can take effective measures which include road pricing and limit the number of motor vehicle.

Projection Moire Interferometry Measurements of Micro Air Vehicle Wings

NASA Technical Reports Server (NTRS)

Fleming, Gary A.; Bartram, Scott M.; Waszak, Martin R.; Jenkins, Luther N.

2001-01-01

Projection Moire Interferometry (PMI) has been used to measure the structural deformation of micro air vehicle (MAV) wings during a series of wind tunnel tests. The MAV wings had a highly flexible wing structure, generically reminiscent of a bat s wing, which resulted in significant changes in wing shape as a function of MAV angle-of-attack and simulated flight speed. This flow-adaptable wing deformation is thought to provide enhanced vehicle stability and wind gust alleviation compared to rigid wing designs. Investigation of the potential aerodynamic benefits of a flexible MAV wing required measurement of the wing shape under aerodynamic loads. PMI was used to quantify the aerodynamically induced changes in wing shape for three MAV wings having different structural designs and stiffness characteristics. This paper describes the PMI technique, its application to MAV testing, and presents a portion of the PMI data acquired for the three different MAV wings tested.

Yaw rate control of an air bearing vehicle

NASA Technical Reports Server (NTRS)

Walcott, Bruce L.

1989-01-01

The results of a 6 week project which focused on the problem of controlling the yaw (rotational) rate the air bearing vehicle used on NASA's flat floor facility are summarized. Contained within is a listing of the equipment available for task completion and an evaluation of the suitability of this equipment. The identification (modeling) process of the air bearing vehicle is detailed as well as the subsequent closed-loop control strategy. The effectiveness of the solution is discussed and further recommendations are included.

Low Earth Orbit Raider (LER) winged air launch vehicle concept

NASA Technical Reports Server (NTRS)

Feaux, Karl; Jordan, William; Killough, Graham; Miller, Robert; Plunk, Vonn

1989-01-01

The need to launch small payloads into low earth orbit has increased dramatically during the past several years. The Low Earth orbit Raider (LER) is an answer to this need. The LER is an air-launched, winged vehicle designed to carry a 1500 pound payload into a 250 nautical mile orbit. The LER is launched from the back of a 747-100B at 35,000 feet and a Mach number of 0.8. Three staged solid propellant motors offer safe ground and flight handling, reliable operation, and decreased fabrication cost. The wing provides lift for 747 separation and during the first stage burn. Also, aerodynamic controls are provided to simplify first stage maneuvers. The air-launch concept offers many advantages to the consumer compared to conventional methods. Launching at 35,000 feet lowers atmospheric drag and other loads on the vehicle considerably. Since the 747 is a mobile launch pad, flexibility in orbit selection and launch time is unparalleled. Even polar orbits are accessible with a decreased payload. Most importantly, the LER launch service can come to the customer, satellites and experiments need not be transported to ground based launch facilities. The LER is designed to offer increased consumer freedom at a lower cost over existing launch systems. Simplistic design emphasizing reliability at low cost allows for the light payloads of the LER.

Mechanically refuelable zinc/air electric vehicle cells

NASA Astrophysics Data System (ADS)

Noring, J.; Gordon, S.; Maimoni, A.; Spragge, M.; Cooper, J. F.

1992-12-01

Refuelable zinc/air batteries have long been considered for motive as well as stationary power because of a combination of high specific energy, low initial cost, and the possibility of mechanical recharge by electrolyte exchange and additions of metallic zinc. In this context, advanced slurry batteries, stationary packed bed cells, and batteries offering replaceable cassettes have been reported recently. The authors are developing self-feeding, particulate-zinc/air batteries for electric vehicle applications. Emissionless vehicle legislation in California motivated efforts to consider a new approach to providing an electric vehicle with long range (400 km), rapid refueling (10 minutes) and highway safe acceleration - factors which define the essential functions of common automobiles. Such an electric vehicle would not compete with emerging secondary battery vehicles in specialized applications (commuting vehicles, delivery trucks). Rather, different markets would be sought where long range or rapid range extension are important. Examples are: taxis, continuous-duty fork-lift trucks and shuttle busses, and general purpose automobiles having modest acceleration capabilities. In the long range, a mature fleet would best use regional plants to efficiently recover zinc from battery reaction products. One option would be to use chemical/thermal reduction to recover the zinc. The work described focuses on development of battery configurations which efficiently and completely consume zinc particles, without clogging or changing discharge characteristics.

Functional design of heat exchange for pneumatic vehicles

NASA Astrophysics Data System (ADS)

Xu, Z. G.; Yang, D. Y.; Shen, W. D.; Liu, T. T.

2017-10-01

With the increasingly serious environmental problems, especially the impact of fog and haze, the development of air powered vehicles has become an important research direction of new energy vehicles. Quadrature test was done with different materials, i.e. stainless steel and aluminum alloy, at different inlet pressures, using different expansion gases, i.e. air, CO2, for heat exchanging properties for pneumatic vehicles. The mathematics as well as simulation methods are used to analyze the different heat exchanging effects in the multistage cylinder. The research results showed that the stainless steel has better effects in heat exchanging than Aluminum Alloy; the intake pressure has little effect on CO2 than the air in heat exchanging effect. CO2 is better in heat exchanging than air.

Cost-effectiveness of integrated analysis/design systems /IPAD/ An executive summary. II. [for aerospace vehicles

NASA Technical Reports Server (NTRS)

Miller, R. E., Jr.; Hansen, S. D.; Redhed, D. D.; Southall, J. W.; Kawaguchi, A. S.

1974-01-01

Evaluation of the cost-effectiveness of integrated analysis/design systems with particular attention to Integrated Program for Aerospace-Vehicle Design (IPAD) project. An analysis of all the ingredients of IPAD indicates the feasibility of a significant cost and flowtime reduction in the product design process involved. It is also concluded that an IPAD-supported design process will provide a framework for configuration control, whereby the engineering costs for design, analysis and testing can be controlled during the air vehicle development cycle.

Next Generation Civil Transport Aircraft Design Considerations for Improving Vehicle and System-Level Efficiency

NASA Technical Reports Server (NTRS)

Acosta, Diana M.; Guynn, Mark D.; Wahls, Richard A.; DelRosario, Ruben,

2013-01-01

The future of aviation will benefit from research in aircraft design and air transportation management aimed at improving efficiency and reducing environmental impacts. This paper presents civil transport aircraft design trends and opportunities for improving vehicle and system-level efficiency. Aircraft design concepts and the emerging technologies critical to reducing thrust specific fuel consumption, reducing weight, and increasing lift to drag ratio currently being developed by NASA are discussed. Advancements in the air transportation system aimed towards system-level efficiency are discussed as well. Finally, the paper describes the relationship between the air transportation system, aircraft, and efficiency. This relationship is characterized by operational constraints imposed by the air transportation system that influence aircraft design, and operational capabilities inherent to an aircraft design that impact the air transportation system.

Environmental Assessment for Air Force Research Laboratory Space Vehicles Integrated Experiments Division Office Space at Kirtland Air Force Base, Albuquerque, New Mexico

DTIC Science & Technology

2005-06-01

AIR FORCE RESEARCH LABORATORY SPACE VEHICLES INTEGRATED EXPERMENTS DIVISION OFFICE SPACE AT KIRTLAND AIR FORCE ... Kirtland Air Force Base (KAFB). The office building would house the Air Force Research Laboratory Space Vehicles Integrated Experiments Division...ADDRESS(ES) Air Force Research Laboratory ,Space Vehicles Directorate,3550 Aberdeen Ave. SE, Kirtland

Ducted Fan Designs Lead to Potential New Vehicles

NASA Technical Reports Server (NTRS)

2010-01-01

In 1994, aerospace engineers Rob Bulaga and Mike Moshier formed Trek Aerospace Inc., based in Folsom, California, to develop personal air vehicles using a novel ducted fan design. The company relied on Ames Research Center for a great deal of testing, the results of which have provided greater lift, lowered weight, more power, and improved maneuverability. The technology has been applied to three models: the Dragonfly UMR-1, the Springtail EFV, and the OVIWUN, a small-scale version that is for sale through the company's Web site. It is safer than a manned vehicle, and its size makes it relatively difficult for it to damage itself during test flights the way a larger mass, faster craft could.

Effect of vehicle type on the performance of second generation air bags for child occupants.

PubMed

Arbogast, Kristy B; Durbin, Dennis R; Kallan, Michael J; Winston, Flaura K

2003-01-01

Passenger air bags experienced considerable design modification in the late 1990s, principally to mitigate risks to child passengers. This study utilized Data from the Partners for Child Passenger Safety study, a large-scale child-focused crash surveillance system, to examine the effect of vehicle type on the differential performance of first and second generation air bags on injuries to restrained children in frontal impact crashes. Our results show that the benefit of second-generation air bags was seen in passenger cars - those children exposed to second-generation air bags were half as likely to sustain a serious injury - and minivans. However, in SUVs the data suggest no reduction in injury risk with the new designs. This field data provides crucial real-world experience to the automotive industry as they work towards the next generation of air bag designs.

Effect of Vehicle type on the Performance of Second Generation Air Bags for Child Occupants

PubMed Central

Arbogast, Kristy B.; Durbin, Dennis R.; Kallan, Michael J.; Winston, Flaura K.

2003-01-01

Passenger air bags experienced considerable design modification in the late 1990s, principally to mitigate risks to child passengers. This study utilized Data from the Partners for Child Passenger Safety study, a large-scale child-focused crash surveillance system, to examine the effect of vehicle type on the differential performance of first and second generation air bags on injuries to restrained children in frontal impact crashes. Our results show that the benefit of second-generation air bags was seen in passenger cars – those children exposed to second-generation air bags were half as likely to sustain a serious injury – and minivans. However, in SUVs the data suggest no reduction in injury risk with the new designs. This field data provides crucial real-world experience to the automotive industry as they work towards the next generation of air bag designs. PMID:12941218

Improving the aluminum-air battery system for use in electrical vehicles

NASA Astrophysics Data System (ADS)

Yang, Shaohua

The objectives of this study include improvement of the efficiency of the aluminum/air battery system and demonstration of its ability for vehicle applications. The aluminum/air battery system can generate enough energy and power for driving ranges and acceleration similar to that of gasoline powered cars. Therefore has the potential to be a power source for electrical vehicles. Aluminum/air battery vehicle life cycle analysis was conducted and compared to that of lead/acid and nickel-metal hydride vehicles. Only the aluminum/air vehicles can be projected to have a travel range comparable to that of internal combustion engine vehicles (ICE). From this analysis, an aluminum/air vehicle is a promising candidate compared to ICE vehicles in terms of travel range, purchase price, fuel cost, and life cycle cost. We have chosen two grades of Al alloys (Al alloy 1350, 99.5% and Al alloy 1199, 99.99%) in our study. Only Al 1199 was studied extensively using Na 2SnO3 as an electrolyte additive. We then varied concentration and temperature, and determined the effects on the parasitic (corrosion) current density and open circuit potential. We also determined cell performance and selectivity curves. To optimize the performance of the cell based on our experiments, the recommended operating conditions are: 3--4 N NaOH, about 55°C, and a current density of 150--300 mA/cm2. We have modeled the cell performance using the equations we developed. The model prediction of cell performance shows good agreement with experimental data. For better cell performance, our model studies suggest use of higher electrolyte flow rate, smaller cell gap, higher conductivity and lower parasitic current density. We have analyzed the secondary current density distributions in a two plane, parallel Al/air cell and a wedge-type Al/air cell. The activity of the cathode has a large effect on the local current density. With increases in the cell gap, the local current density increases, but the increase is

The Role of Design-of-Experiments in Managing Flow in Compact Air Vehicle Inlets

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.; Miller, Daniel N.; Gridley, Marvin C.; Agrell, Johan

2003-01-01

It is the purpose of this study to demonstrate the viability and economy of Design-of-Experiments methodologies to arrive at microscale secondary flow control array designs that maintain optimal inlet performance over a wide range of the mission variables and to explore how these statistical methods provide a better understanding of the management of flow in compact air vehicle inlets. These statistical design concepts were used to investigate the robustness properties of low unit strength micro-effector arrays. Low unit strength micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. The term robustness is used in this paper in the same sense as it is used in the industrial problem solving community. It refers to minimizing the effects of the hard-to-control factors that influence the development of a product or process. In Robustness Engineering, the effects of the hard-to-control factors are often called noise , and the hard-to-control factors themselves are referred to as the environmental variables or sometimes as the Taguchi noise variables. Hence Robust Optimization refers to minimizing the effects of the environmental or noise variables on the development (design) of a product or process. In the management of flow in compact inlets, the environmental or noise variables can be identified with the mission variables. Therefore this paper formulates a statistical design methodology that minimizes the impact of variations in the mission variables on inlet performance and demonstrates that these statistical design concepts can lead to simpler inlet flow management systems.

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

PubMed Central

Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

2017-01-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50–75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants’ exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation. PMID:28781568

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air.

PubMed

Jung, Heejung S; Grady, Michael L; Victoroff, Tristan; Miller, Arthur L

2017-07-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO 2 ) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO 2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm 3 , although CO 2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO 2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm 3 . We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO 2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO 2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO 2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO 2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO 2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO 2 accumulation.

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

NASA Astrophysics Data System (ADS)

Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

2017-07-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation.

Utilizing adaptive wing technology in the control of a micro air vehicle

NASA Astrophysics Data System (ADS)

Null, William R.; Wagner, Matthew G.; Shkarayev, Sergey V.; Jouse, Wayne C.; Brock, Keith M.

2002-07-01

Evolution of the design of micro air vehicles (MAVs) towards miniaturization has been severely constrained by the size and mass of the electronic components needed to control the vehicles. Recent research, experimentation, and development in the area of smart materials have led to the possibility of embedding control actuators, fabricated from smart materials, in the wing of the vehicle, reducing both the size and mass of these components. Further advantages can be realized by developing adaptive wing structures. Small size and mass, and low airspeeds, can lead to considerable buffeting during flight, and may result in a loss of flight control. In order to counter these effects, we are developing a thin, variable-cambered airfoil design with actuators embedded within the wing. In addition to reducing the mass and size of the vehicle or, conversely, increasing its available payload, an important benefit from the adaptive wing concept is the possibility of in-flight modification of the flight envelope. Reduced airspeeds, which are crucial during loiter, can be realized by an in-flight increase in wing camber. Conversely, decreases in camber provide for an airframe best suited for rapid ingress/egress and extension of the mission range.

Numerical study for flame deflector design of a space launch vehicle

NASA Astrophysics Data System (ADS)

Oh, Hwayoung; Lee, Jungil; Um, Hyungsik; Huh, Hwanil

2017-04-01

A flame deflector is a structure that prevents damage to a launch vehicle and a launch pad due to exhaust plumes of a lifting-off launch vehicle. The shape of a flame deflector should be designed to restrain the discharged gas from backdraft inside the deflector and to reflect the impact to the surrounding environment and the engine characteristics of the vehicle. This study presents the five preliminary flame deflector configurations which are designed for the first-stage rocket engine of the Korea Space Launch Vehicle-II and surroundings of the Naro space center. The gas discharge patterns of the designed flame deflectors are investigated using the 3D flow field analysis by assuming that the air, in place of the exhaust gas, forms the plume. In addition, a multi-species unreacted flow model is investigated through 2D analysis of the first-stage engine of the KSLV-II. The results indicate that the closest Mach number and temperature distributions to the reacted flow model can be achieved from the 4-species unreacted flow model which employs H2O, CO2, and CO and specific heat-corrected plume.

Vehicle safety : technologies, challenges, and research development expenditures for advanced air bags

DOT National Transportation Integrated Search

2001-06-01

Some advanced air bag technologies are currently being installed in vehicles and others are still being developed. The principal advanced technology that is currently being installed in some vehicles is air bags that can inflate with lower or higher ...

Design and analysis of Air flow duct for improving the thermal performance of disc brake rotor

NASA Astrophysics Data System (ADS)

Raja, T.; Mathiselvan, G.; Sreenivasulureddy, M.; Goldwin Xavier, X.

2017-05-01

safety in automotive engineering has been considered as a number one priority in development of new vehicle. A brake system is one of the most critical systems in the vehicle, without which the vehicle will put a passenger in an unsafe position. Temperature distribution on disc rotor brake and the performance brake of disc rotor is influenced by the air flow around the disc rotor. In this paper, the effect of air flow over the disc rotor is analyzed using the CFD software. The air flow over the disc rotor is increased by using a duct to supply more air flow over the disc rotor. The duct is designed to supply more air to the rotor surface and it can be placed in front of the vehicle for better performance. Increasing the air flow around the rotor will maximize the heat convection from the rotor surface. The rotor life and the performance can be improved.

A Capability to Generate Physics-based Mass Estimating Relationships for Conceptual Space Vehicle Design

NASA Technical Reports Server (NTRS)

Olds, John R.; Marcus, Leland

2002-01-01

This paper is written in support of the on-going research into conceptual space vehicle design conducted at the Space Systems Design Laboratory (SSDL) at the Georgia Institute of Technology. Research at the SSDL follows a sequence of a number of the traditional aerospace disciplines. The sequence of disciplines and interrelationship among them is shown in the Design Structure Matrix (DSM). The discipline of Weights and Sizing occupies a central location in the design of a new space vehicle. Weights and Sizing interact, either in a feed forward or feed back manner, with every other discipline in the DSM. Because of this principle location, accuracy in Weights and Sizing is integral to producing an accurate model of a space vehicle concept. Instead of using conceptual level techniques, a simplified Finite Element Analysis (FEA) technique is described as applied to the problem of the Liquid Oxygen (LOX) tank bending loads applied to the forward Liquid Hydrogen (LH2) tank of the Georgia Tech Air Breathing Launch Vehicle (ABLV).

Aerospace vehicle design, spacecraft section. Volume 1

NASA Technical Reports Server (NTRS)

1988-01-01

The objective was to create a manned Martian aircraft which can perform: scientific surveys of particular sites distant from the base; a deployment of scientific instrument packages by air drop that land rovers cannot accomplish; and rescue operations. Designing the airfoil requires a wing which can operate within the low Reynolds numbers apparent on Mars. The airfoil, NASA NLF(1)-1015 was chosen. The design of the aircraft is comparable to a P-38 military aircraft. The aircraft uses fuel cells to power the two propellers. A rocket-assisted takeoff is necessary to enable Romulus to liftoff. Although the design and creation of Romulus would be an expensive adventure, such a vehicle could be most useful in evaluating the Mars surface and in creating a habitat for mankind.

Delta Clipper vehicle design for supportability

NASA Astrophysics Data System (ADS)

Smiljanic, Ray R.; Klevatt, Paul L.; Steinmeyer, Donald A.

1993-02-01

The paper describes the Single Stage Rocket Technology (SSRT) Delta Clipper vehicle design. As a means of reducing vehicle processing and turnaround times, the SSRT Delta Clipper design, contrary to past practices, incorporates support ability engineering features into its initial set of design requirements. The engineering process used to 'design-in' supportability into the Delta Clipper vehicle is described in detail and is illustrated using diagrams.

Interactions between Flight Dynamics and Propulsion Systems of Air-Breathing Hypersonic Vehicles

NASA Astrophysics Data System (ADS)

Dalle, Derek J.

The development and application of a first-principles-derived reduced-order model called MASIV (Michigan/AFRL Scramjet In Vehicle) for an air-breathing hypersonic vehicle is discussed. Several significant and previously unreported aspects of hypersonic flight are investigated. A fortunate coupling between increasing Mach number and decreasing angle of attack is shown to extend the range of operating conditions for a class of supersonic inlets. Detailed maps of isolator unstart and ram-to-scram transition are shown on the flight corridor map for the first time. In scram mode the airflow remains supersonic throughout the engine, while in ram mode there is a region of subsonic flow. Accurately predicting the transition between these two modes requires models for complex shock interactions, finite-rate chemistry, fuel-air mixing, pre-combustion shock trains, and thermal choking, which are incorporated into a unified framework here. Isolator unstart occurs when the pre-combustion shock train is longer than the isolator, which blocks airflow from entering the engine. Finally, cooptimization of the vehicle design and trajectory is discussed. An optimal control technique is introduced that greatly reduces the number of computations required to optimize the simulated trajectory.

Autonomous Soaring for Improved Endurance of a Small Uninhabited Air Vehicle

NASA Technical Reports Server (NTRS)

Allen, Michael J.

2005-01-01

A relatively unexplored method to improve the endurance of an autonomous aircraft is to use buoyant plumes of air found in the lower atmosphere called thermals or updrafts. Glider pilots and birds commonly use updrafts to improve range, endurance, or cross-country speed. This report presents a quantitative analysis of a small electric-powered uninhabited air vehicle using updrafts to extend its endurance over a target location. A three-degree-of-freedom simulation of the uninhabited air vehicle was used to determine the yearly effect of updrafts on performance. Surface radiation and rawinsonde balloon measurements taken at Desert Rock, Nevada, were used to determine updraft size, strength, spacing, shape, and maximum height for the simulation. A fixed-width spiral path was used to search for updrafts at the same time as maintaining line-of-sight to the surface target position. Power was used only when the aircraft was flying at the lower-altitude limit in search of updrafts. Results show that an uninhabited air vehicle with a nominal endurance of 2 hours can fly a maximum of 14 hours using updrafts during the summer and a maximum of 8 hours during the winter. The performance benefit and the chance of finding updrafts both depend on what time of day the uninhabited air vehicle is launched. Good endurance and probability of finding updrafts during the year was obtained when the uninhabited air vehicle was launched 30 percent into the daylight hours after sunrise each day. Yearly average endurance was found to be 8.6 hours with these launch times.

Multidisciplinary Modeling Software for Analysis, Design, and Optimization of HRRLS Vehicles

NASA Technical Reports Server (NTRS)

Spradley, Lawrence W.; Lohner, Rainald; Hunt, James L.

2011-01-01

The concept for Highly Reliable Reusable Launch Systems (HRRLS) under the NASA Hypersonics project is a two-stage-to-orbit, horizontal-take-off / horizontal-landing, (HTHL) architecture with an air-breathing first stage. The first stage vehicle is a slender body with an air-breathing propulsion system that is highly integrated with the airframe. The light weight slender body will deflect significantly during flight. This global deflection affects the flow over the vehicle and into the engine and thus the loads and moments on the vehicle. High-fidelity multi-disciplinary analyses that accounts for these fluid-structures-thermal interactions are required to accurately predict the vehicle loads and resultant response. These predictions of vehicle response to multi physics loads, calculated with fluid-structural-thermal interaction, are required in order to optimize the vehicle design over its full operating range. This contract with ResearchSouth addresses one of the primary objectives of the Vehicle Technology Integration (VTI) discipline: the development of high-fidelity multi-disciplinary analysis and optimization methods and tools for HRRLS vehicles. The primary goal of this effort is the development of an integrated software system that can be used for full-vehicle optimization. This goal was accomplished by: 1) integrating the master code, FEMAP, into the multidiscipline software network to direct the coupling to assure accurate fluid-structure-thermal interaction solutions; 2) loosely-coupling the Euler flow solver FEFLO to the available and proven aeroelasticity and large deformation (FEAP) code; 3) providing a coupled Euler-boundary layer capability for rapid viscous flow simulation; 4) developing and implementing improved Euler/RANS algorithms into the FEFLO CFD code to provide accurate shock capturing, skin friction, and heat-transfer predictions for HRRLS vehicles in hypersonic flow, 5) performing a Reynolds-averaged Navier-Stokes computation on an HRRLS

Research on Vehicle Temperature Regulation System Based on Air Convection Principle

NASA Astrophysics Data System (ADS)

Zhuge, Muzi; Li, Xiang; Liang, Caifeng

2018-03-01

The long time parking outdoors in the summer will lead to too high temperature in the car, and the harmful gas produced by the vehicle engine will stay in the confined space for a long time during the parking process, which will do great harm to the human body. If the air conditioning system is turned on before driving, the cooling rate is slow and the battery loss is large. To solve the above problems, we designed a temperature adjusting system based on the principle of air convection. We can choose the automatic mode or manual mode to achieve control of a convection window. In the automatic mode, the system will automatically detect the environmental temperature, through the sensor to complete the detection, and the signal is transmitted to the microcontroller to control the window open or close, in manual mode, the remote control of the window can be realized by Bluetooth. Therefore, the system has important practical significance to effectively regulate temperature, prolong battery life, and improve the safety and comfort of traffic vehicles.

Infrared measurement and composite tracking algorithm for air-breathing hypersonic vehicles

NASA Astrophysics Data System (ADS)

Zhang, Zhao; Gao, Changsheng; Jing, Wuxing

2018-03-01

Air-breathing hypersonic vehicles have capabilities of hypersonic speed and strong maneuvering, and thus pose a significant challenge to conventional tracking methodologies. To achieve desirable tracking performance for hypersonic targets, this paper investigates the problems related to measurement model design and tracking model mismatching. First, owing to the severe aerothermal effect of hypersonic motion, an infrared measurement model in near space is designed and analyzed based on target infrared radiation and an atmospheric model. Second, using information from infrared sensors, a composite tracking algorithm is proposed via a combination of the interactive multiple models (IMM) algorithm, fitting dynamics model, and strong tracking filter. During the procedure, the IMMs algorithm generates tracking data to establish a fitting dynamics model of the target. Then, the strong tracking unscented Kalman filter is employed to estimate the target states for suppressing the impact of target maneuvers. Simulations are performed to verify the feasibility of the presented composite tracking algorithm. The results demonstrate that the designed infrared measurement model effectively and continuously observes hypersonic vehicles, and the proposed composite tracking algorithm accurately and stably tracks these targets.

Design and development of a biomimetic device for micro air vehicles

NASA Astrophysics Data System (ADS)

Bohorquez, Felipe; Pines, Darryll J.

2002-07-01

This paper presents the design and development of a pitching and plunging (flapping) mechanism for small-scale flight. In order to harness the unsteady lift mechanisms, used by most insects, a biologically inspired flapping/pitching device in conjunction with a rotary wing concept was developed and built. This mechanism attempts to replicate some of the aerodynamic phenomena that enhance the performance of small fliers, replacing the periodic translational motion with a unidirectional circular motion while actively flapping and pitching the rotor blades. In order to find the appropriate combination of phase, amplitude, frequency and rotational speed that leads to enhancement in lift, the device requires uncoupled independent pitch and flap actuation systems to permit the complete mapping of the parameter space. In the device under consideration the phase shift between the flapping and the pitching oscillations can be adjusted from 0 to 360 degrees over a wide range of rotational speeds. Maximum flapping and pitching amplitudes of +/- 23 degree(s) and +/- 20 degree(s) respectively can be attained. Linear displacements of two coaxial shafts are translated into the flapping and pitching motion of the rotor blades. The mechanism was designed to minimize the actuation stroke so that smart materials and conventional actuators such as motors and cams could be used. Kinematic analysis as well as experimental tests were performed. Using a customized test stand thrust and torque produced by the rotor were measured at different angles of attack, in steady-state and under periodical pitching actuation. The results showed that hover efficiency was considerably increased for a range of thrust coefficients. The device was developed based on the University of Maryland's rotary wing Micro Air vehicle (MAV) the MICOR (MIcro COaxial Rotorcraft), an electrically driven 100 g coaxial helicopter. It is anticipated that active flapping and/or pitching could be implemented in the

Hypersonic drone vehicle design: A multidisciplinary experience

NASA Technical Reports Server (NTRS)

1988-01-01

UCLA's Advanced Aeronautic Design group focussed their efforts on design problems of an unmanned hypersonic vehicle. It is felt that a scaled hypersonic drone is necesary to bridge the gap between present theory on hypersonics and the future reality of the National Aerospace Plane (NASP) for two reasons: (1) to fulfill a need for experimental data in the hypersonic regime, and (2) to provide a testbed for the scramjet engine which is to be the primary mode of propulsion for the NASP. The group concentrated on three areas of great concern to NASP design: propulsion, thermal management, and flight systems. Problem solving in these areas was directed toward design of the drone with the idea that the same design techniques could be applied to the NASP. A 70 deg swept double-delta wing configuration, developed in the 70's at the NASA Langley, was chosen as the aerodynamic and geometric model for the drone. This vehicle would be air launched from a B-1 at Mach 0.8 and 48,000 feet, rocket boosted by two internal engines to Mach 10 and 100,000 feet, and allowed to cruise under power of the scramjet engine until burnout. It would then return to base for an unpowered landing. Preliminary energy calculations based on flight requirements give the drone a gross launch weight of 134,000 pounds and an overall length of 85 feet.

Novel Aerodynamic Design for Formula SAE Vehicles

NASA Astrophysics Data System (ADS)

Sentongo, Samuel; Carter, Austin; Cecil, Christopher; Feier, Ioan

2017-11-01

This paper identifies and evaluates the design characteristics of a novel airfoil that harnesses the Magnus Effect, applying a moving-surface boundary-layer control (MSBC) method to a Formula SAE Vehicle. The MSBC minimizes adverse pressure gradient and delays boundary layer separation through the use of a conveyor belt that interacts with the airfoil boundary layer. The MSBC allows dynamic control of the aerodynamic coefficients by variation of the belt speed, minimizing drag in high speed straights and maximizing downforce during vehicle cornering. A conveyer belt wing measuring approximately 0.9 x 0.9m in planform was designed and built to test the mechanical setup for such a MSBC wing. This study follows the relationship between inputted power and outputted surface velocity, with the goal being to maximize speed output vs. power input. The greatest hindrance to maximizing speed output is friction among belts, rollers, and stationary members. The maximum belt speed achieved during testing was 5.9 m/s with a power input of 48.8 W, which corresponds to 45.8 N of downforce based on 2D CFD results. Ongoing progress on this project is presented. United States Air Force Academy.

High Altitude Long Endurance Air Vehicle Analysis of Alternatives and Technology Requirements Development

NASA Technical Reports Server (NTRS)

Nickol, Craig L.; Guynn, Mark D.; Kohout, Lisa L.; Ozoroski, Thomas A.

2007-01-01

The objective of this study was to develop a variety of High Altitude Long Endurance (HALE) Unmanned Aerial Vehicle (UAV) conceptual designs for two operationally useful missions (hurricane science and communications relay) and compare their performance and cost characteristics. Sixteen potential HALE UAV configurations were initially developed, including heavier-than-air (HTA) and lighter-than-air (LTA) concepts with both consumable fuel and solar regenerative (SR) propulsion systems. Through an Analysis of Alternatives (AoA) down select process, the two leading consumable fuel configurations (one each from the HTA and LTA alternatives) and an HTA SR configuration were selected for further analysis. Cost effectiveness analysis of the consumable fuel configurations revealed that simply maximizing vehicle endurance can lead to a sub-optimum system solution. An LTA concept with a hybrid propulsion system (solar arrays and a hydrogen-air proton exchange membrane fuel cell) was found to have the best mission performance; however, an HTA diesel-fueled wing-body-tail configuration emerged as the preferred consumable fuel concept because of the large size and technical risk of the LTA concept. The baseline missions could not be performed by even the best HTA SR concept. Mission and SR technology trade studies were conducted to enhance understanding of the potential capabilities of such a vehicle. With near-term technology SR-powered HTA vehicles are limited to operation in favorable solar conditions, such as the long days and short nights of summer at higher latitudes. Energy storage system specific energy and solar cell efficiency were found to be the key technology areas for enhancing HTA SR performance.

A primer on motor vehicle air pollution.

DOT National Transportation Integrated Search

1973-01-01

This primer presents a brief state-of-the art review of motor vehicle air pollution. Its purpose is to aid highway personnel in understanding the nature of this environmental problem on our highways and to present possible solutions for its abatement...

Survey of Aerothermodynamics Facilities Useful for the Design of Hypersonic Vehicles Using Air-Breathing Propulsion

NASA Technical Reports Server (NTRS)

Arnold, James O.; Deiwert, G. S.

1997-01-01

The dream of producing an air-breathing, hydrogen fueled, hypervelocity aircraft has been before the aerospace community for decades. However, such a craft has not yet been realized, even in an experimental form. Despite the simplicity and beauty of the concept, many formidable problems must be overcome to make this dream a reality. This paper summarizes the aero/aerothermodynamic issues that must be addressed to make the dream a reality and discusses how aerothermodynamics facilities and their modem companion, real-gas computational fluid dynamics (CFD), can help solve the problems blocking the way to realizing the dream. The approach of the paper is first to outline the concept of an air-breathing hypersonic vehicle and then discuss the nose-to-tail aerothermodynamics issues and special aerodynamic problems that arise with such a craft. Then the utility of aerothermodynamic facilities and companion CFD analysis is illustrated by reviewing results from recent United States publications wherein these problems have been addressed. Papers selected for the discussion have k e n chosen such that the review will serve to survey important U.S. aero/aerothermodynamic real gas and conventional wind tunnel facilities that are useful in the study of hypersonic, hydrogen propelled hypervelocity vehicles.

The design of two-stage-to-orbit vehicles

NASA Technical Reports Server (NTRS)

1991-01-01

Two separate student design groups developed conceptual designs for a two-stage-to-orbit vehicle, with each design group consisting of a carrier team and an orbiter team. A two-stage-to-orbit system is considered in the event that single-stage-to-orbit is deemed not feasible in the foreseeable future; the two-stage system would also be used as a complement to an already existing heavy lift vehicle. The design specifications given are to lift a 10,000-lb payload 27 ft long by 10 ft diameter, to low Earth orbit (300 n.m.) using an air breathing carrier configuration that will take off horizontally within 15,000 ft. The staging Mach number and altitude were to be determined by the design groups. One group designed a delta wing/body carrier with the orbiter nested within the fuselage of the carrier, and the other group produced a blended cranked-delta wing/body carrier with the orbiter in the more conventional piggyback configuration. Each carrier used liquid hydrogen-fueled turbofanramjet engines, with data provided by General Electric Aircraft Engine Group. While one orbiter used a full-scale Space Shuttle Main Engine (SSME), the other orbiter employed a half-scale SSME coupled with scramjet engines, with data again provided by General Electric. The two groups conceptual designs, along with the technical trade-offs, difficulties, and details that surfaced during the design process are presented.

9 CFR 3.15 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2014 CFR

2014-01-01

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9 CFR 3.138 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2013 CFR

2013-01-01

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9 CFR 3.88 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2014 CFR

2014-01-01

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9 CFR 3.62 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2011 CFR

2011-01-01

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9 CFR 3.138 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2011 CFR

2011-01-01

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9 CFR 3.138 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2014 CFR

2014-01-01

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9 CFR 3.62 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2010 CFR

2010-01-01

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9 CFR 3.138 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2010 CFR

2010-01-01

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9 CFR 3.62 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2012 CFR

2012-01-01

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9 CFR 3.15 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2012 CFR

2012-01-01

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9 CFR 3.88 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2011 CFR

2011-01-01

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9 CFR 3.62 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2013 CFR

2013-01-01

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9 CFR 3.88 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2013 CFR

2013-01-01

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9 CFR 3.15 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2013 CFR

2013-01-01

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9 CFR 3.62 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2014 CFR

2014-01-01

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9 CFR 3.138 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2012 CFR

2012-01-01

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9 CFR 3.88 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2010 CFR

2010-01-01

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9 CFR 3.88 - Primary conveyances (motor vehicle, rail, air, and marine).

Code of Federal Regulations, 2012 CFR

2012-01-01

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Design of a high altitude long endurance flying-wing solar-powered unmanned air vehicle

NASA Astrophysics Data System (ADS)

Alsahlani, A. A.; Johnston, L. J.; Atcliffe, P. A.

2017-06-01

The low-Reynolds number environment of high-altitude §ight places severe demands on the aerodynamic design and stability and control of a high altitude, long endurance (HALE) unmanned air vehicle (UAV). The aerodynamic efficiency of a §ying-wing configuration makes it an attractive design option for such an application and is investigated in the present work. The proposed configuration has a high-aspect ratio, swept-wing planform, the wing sweep being necessary to provide an adequate moment arm for outboard longitudinal and lateral control surfaces. A design optimization framework is developed under a MATLAB environment, combining aerodynamic, structural, and stability analysis. Low-order analysis tools are employed to facilitate efficient computations, which is important when there are multiple optimization loops for the various engineering analyses. In particular, a vortex-lattice method is used to compute the wing planform aerodynamics, coupled to a twodimensional (2D) panel method to derive aerofoil sectional characteristics. Integral boundary-layer methods are coupled to the panel method in order to predict §ow separation boundaries during the design iterations. A quasi-analytical method is adapted for application to flyingwing con¦gurations to predict the wing weight and a linear finite-beam element approach is used for structural analysis of the wing-box. Stability is a particular concern in the low-density environment of high-altitude flight for flying-wing aircraft and so provision of adequate directional stability and control power forms part of the optimization process. At present, a modified Genetic Algorithm is used in all of the optimization loops. Each of the low-order engineering analysis tools is validated using higher-order methods to provide con¦dence in the use of these computationally-efficient tools in the present design-optimization framework. This paper includes the results of employing the present optimization tools in the design of a

Damage Considerations of a Flexible Micro Air Vehicle Wing Using 3-D Laser Vibrometry

DTIC Science & Technology

2007-06-01

AIR VEHICLE WING USING 3-D LASER VIBROMETRY THESIS Leo L. Mendoza Jr., ENS, USN AFIT/GAE/ENY/07-J13 DEPARTMENT OF THE AIR FORCE AIR ...3-D LASER VIBROMETRY THESIS Presented to the Faculty Department of Aeronautical and Astronautical Engineering Air Force...DISTRIBUTION UNLIMITED AFIT/GAE/ENY/07-J13 DAMAGE CONSIDERATIONS OF A FLEXIBLE MICRO AIR VEHICLE WING USING 3-D LASER VIBROMETRY

The Application of the NASA Advanced Concepts Office, Launch Vehicle Team Design Process and Tools for Modeling Small Responsive Launch Vehicles

NASA Technical Reports Server (NTRS)

Threet, Grady E.; Waters, Eric D.; Creech, Dennis M.

2012-01-01

The Advanced Concepts Office (ACO) Launch Vehicle Team at the NASA Marshall Space Flight Center (MSFC) is recognized throughout NASA for launch vehicle conceptual definition and pre-phase A concept design evaluation. The Launch Vehicle Team has been instrumental in defining the vehicle trade space for many of NASA s high level launch system studies from the Exploration Systems Architecture Study (ESAS) through the Augustine Report, Constellation, and now Space Launch System (SLS). The Launch Vehicle Team s approach to rapid turn-around and comparative analysis of multiple launch vehicle architectures has played a large role in narrowing the design options for future vehicle development. Recently the Launch Vehicle Team has been developing versions of their vetted tools used on large launch vehicles and repackaged the process and capability to apply to smaller more responsive launch vehicles. Along this development path the LV Team has evaluated trajectory tools and assumptions against sounding rocket trajectories and air launch systems, begun altering subsystem mass estimating relationships to handle smaller vehicle components, and as an additional development driver, have begun an in-house small launch vehicle study. With the recent interest in small responsive launch systems and the known capability and response time of the ACO LV Team, ACO s launch vehicle assessment capability can be utilized to rapidly evaluate the vast and opportune trade space that small launch vehicles currently encompass. This would provide a great benefit to the customer in order to reduce that large trade space to a select few alternatives that should best fit the customer s payload needs.

Computational fluid dynamics challenges for hybrid air vehicle applications

NASA Astrophysics Data System (ADS)

Carrin, M.; Biava, M.; Steijl, R.; Barakos, G. N.; Stewart, D.

2017-06-01

This paper begins by comparing turbulence models for the prediction of hybrid air vehicle (HAV) flows. A 6 : 1 prolate spheroid is employed for validation of the computational fluid dynamics (CFD) method. An analysis of turbulent quantities is presented and the Shear Stress Transport (SST) k-ω model is compared against a k-ω Explicit Algebraic Stress model (EASM) within the unsteady Reynolds-Averaged Navier-Stokes (RANS) framework. Further comparisons involve Scale Adaptative Simulation models and a local transition transport model. The results show that the flow around the vehicle at low pitch angles is sensitive to transition effects. At high pitch angles, the vortices generated on the suction side provide substantial lift augmentation and are better resolved by EASMs. The validated CFD method is employed for the flow around a shape similar to the Airlander aircraft of Hybrid Air Vehicles Ltd. The sensitivity of the transition location to the Reynolds number is demonstrated and the role of each vehicle£s component is analyzed. It was found that the ¦ns contributed the most to increase the lift and drag.

The Digital Twin Paradigm for Future NASA and U.S. Air Force Vehicles

NASA Technical Reports Server (NTRS)

Glaessgen, Edward H.; Stargel, D. S.

2012-01-01

Future generations of NASA and U.S. Air Force vehicles will require lighter mass while being subjected to higher loads and more extreme service conditions over longer time periods than the present generation. Current approaches for certification, fleet management and sustainment are largely based on statistical distributions of material properties, heuristic design philosophies, physical testing and assumed similitude between testing and operational conditions and will likely be unable to address these extreme requirements. To address the shortcomings of conventional approaches, a fundamental paradigm shift is needed. This paradigm shift, the Digital Twin, integrates ultra-high fidelity simulation with the vehicle s on-board integrated vehicle health management system, maintenance history and all available historical and fleet data to mirror the life of its flying twin and enable unprecedented levels of safety and reliability.

Advances in fuel cell vehicle design

NASA Astrophysics Data System (ADS)

Bauman, Jennifer

Factors such as global warming, dwindling fossil fuel reserves, and energy security concerns combine to indicate that a replacement for the internal combustion engine (ICE) vehicle is needed. Fuel cell vehicles have the potential to address the problems surrounding the ICE vehicle without imposing any significant restrictions on vehicle performance, driving range, or refuelling time. Though there are currently some obstacles to overcome before attaining the widespread commercialization of fuel cell vehicles, such as improvements in fuel cell and battery durability, development of a hydrogen infrastructure, and reduction of high costs, the fundamental concept of the fuel cell vehicle is strong: it is efficient, emits zero harmful emissions, and the hydrogen fuel can be produced from various renewable sources. Therefore, research on fuel cell vehicle design is imperative in order to improve vehicle performance and durability, increase efficiency, and reduce costs. This thesis makes a number of key contributions to the advancement of fuel cell vehicle design within two main research areas: powertrain design and DC/DC converters. With regards to powertrain design, this research first analyzes various powertrain topologies and energy storage system types. Then, a novel fuel cell-battery-ultracapacitor topology is presented which shows reduced mass and cost, and increased efficiency, over other promising topologies found in the literature. A detailed vehicle simulator is created in MATLAB/Simulink in order to simulate and compare the novel topology with other fuel cell vehicle powertrain options. A parametric study is performed to optimize each powertrain and general conclusions for optimal topologies, as well as component types and sizes, for fuel cell vehicles are presented. Next, an analytical method to optimize the novel battery-ultracapacitor energy storage system based on maximizing efficiency, and minimizing cost and mass, is developed. This method can be applied

Based on Artificial Neural Network to Realize K-Parameter Analysis of Vehicle Air Spring System

NASA Astrophysics Data System (ADS)

Hung, San-Shan; Hsu, Chia-Ning; Hwang, Chang-Chou; Chen, Wen-Jan

2017-10-01

In recent years, because of the air-spring control technique is more mature, that air- spring suspension systems already can be used to replace the classical vehicle suspension system. Depend on internal pressure variation of the air-spring, thestiffnessand the damping factor can be adjusted. Because of air-spring has highly nonlinear characteristic, therefore it isn’t easy to construct the classical controller to control the air-spring effectively. The paper based on Artificial Neural Network to propose a feasible control strategy. By using offline way for the neural network design and learning to the air-spring in different initial pressures and different loads, offline method through, predict air-spring stiffness parameter to establish a model. Finally, through adjusting air-spring internal pressure to change the K-parameter of the air-spring, realize the well dynamic control performance of air-spring suspension.

Multi-hole pressure probes to air data system for subsonic small-scale air vehicles

NASA Astrophysics Data System (ADS)

Shevchenko, A. M.; Berezin, D. R.; Puzirev, L. N.; Tarasov, A. Z.; Kharitonov, A. M.; Shmakov, A. S.

2016-10-01

A brief review of research performed to develop multi-hole probes to measure of aerodynamic angles, dynamic head, and static pressure of a flying vehicle. The basis of these works is the application a well-known classical multi-hole pressure probe technique of measuring of a 3D flow to use in the air data system. Two multi-hole pressure probes with spherical and hemispherical head to air-data system for subsonic small-scale vehicles have been developed. A simple analytical probe model with separation of variables is proposed. The probes were calibrated in the wind tunnel, one of them is in-flight tested.

Survey of Aerothermodynamics Facilities Useful for the Design of Hypersonic Vehicles Using Air-Breathing Propulsion

NASA Technical Reports Server (NTRS)

Arnold, James O.; Deiwert, George S.

1997-01-01

This paper surveys the use of aerothermodynamic facilities which have been useful in the study of external flows and propulsion aspects of hypersonic, air-breathing vehicles. While the paper is not a survey of all facilities, it covers the utility of shock tunnels and conventional hypersonic blow-down facilities which have been used for hypersonic air-breather studies. The problems confronting researchers in the field of aerothermodynamics are outlined. Results from the T5 GALCIT tunnel for the shock-on lip problem are outlined. Experiments on combustors and short expansion nozzles using the semi-free jet method have been conducted in large shock tunnels. An example which employed the NASA Ames 16-Inch shock tunnel is outlined, and the philosophy of the test technique is described. Conventional blow-down hypersonic wind tunnels are quite useful in hypersonic air-breathing studies. Results from an expansion ramp experiment, simulating the nozzle on a hypersonic air-breather from the NASA Ames 3.5 Foot Hypersonic wind tunnel are summarized. Similar work on expansion nozzles conducted in the NASA Langley hypersonic wind tunnel complex is cited. Free-jet air-frame propulsion integration and configuration stability experiments conducted at Langley in the hypersonic wind tunnel complex on a small generic model are also summarized.

Optimal Design of a Hexakis Icosahedron Vacuum Based Lighter than Air Vehicle

DTIC Science & Technology

2017-03-23

box objectives and constraints. Results for a number of designs are presented and compared . iv Acknowledgements I would like to thank my advisors...Air Force Institute of Technology AFIT Scholar Theses and Dissertations 3-23-2017 Optimal Design of a Hexakis Icosahedron Vacuum Based Lighter than...administrator of AFIT Scholar. For more information, please contact richard.mansfield@afit.edu. Recommended Citation Schwemmer, Joseph R., "Optimal Design of a

Air lifted and propelled vehicle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, T.E.; Johnson, R.A.

1987-02-17

This patent describes a vehicle which rides on air cushion and which is propelled by air, comprising: upper deck means, having a bottom edge which defines the periphery of an area; a thin, flexible sheet located below the upper deck means, extending beneath the bottom edge and secured beneath the bottom edge for defining a plenum that is defined by and closed off by the upper deck means and the sheet. The deck means is shaped within the area defined by its bottom edge for causing the plenum to always be an open space and the upper deck means ismore » rigid enough to maintain that open condition of the plenum; the sheet being secured in a manner permitting the sheet to pillow when air is pressurized in the plenum; and the sheet being perforated below the upper deck means for permitting exit of air from the plenum at a controllable rate through the perforations; the sheet having a large plurality of the perforations dispersed over most of its area below the upper deck means; each of the perforations being a hole.« less

Australian Air Breathing Propulsion Research for Hypersonic, Beamed Energy-Propelled Vehicles

NASA Astrophysics Data System (ADS)

Froning, David

2010-05-01

A three year laser-propelled vehicle analysis and design investigation has been begun in June, 2009 by Faculty and graduate students at the University of Adelaide under a Grant/Cooperative Agreement Award to the University of Adelaide by the Asian Office of Aerospace Research and Development (AOARD). The major objectives of thsis investigation are: (a) development of hypersonic, air breathing "lightcraft" with innovative air inlets that enable acceptable airflow capture and combustion, and acceptable cowl-lip heating rates during hot, high-speed, high angle-of-attack hypersonic flight; (b) yest of the most promising lightcraft and inlet design in the high power laser beam that is part of the shock tunnel facility at CTO Instituto in Brazil; and (c) plan a series of laser guided and propelled flights that achieve supersonic or higher speed at the Woomera Test Facility (WTF) in South Australia—using the existing WTF launching and tracking facilities and sponsor-provided laser pointing and tracking and illumination systems.

How have changes in air bag designs affected frontal crash mortality?

PubMed

Braver, Elisa R; Shardell, Michelle; Teoh, Eric R

2010-07-01

To determine whether front air bag changes have affected occupant protection, frontal crash mortality rates were compared among front outboard occupants in vehicles having certified-advanced air bags (latest generation of air bags) or sled-certified air bags with and without advanced features. Poisson marginal structural models were used to calculate standardized mortality rate ratios (MRRs) for front occupants per registered vehicle. Vehicle age-corrected mortality rates were lower for drivers of vehicles having sled-certified air bags with advanced features than for drivers having sled-certified air bags without advanced features (MRR = 0.88; 95% confidence interval [CI]: 0.81-0.95), including unbelted men and drivers younger than 60. The mortality rate was higher, though not statistically significant, for drivers having certified-advanced air bags compared with sled-certified air bags with advanced features (vehicle age-corrected MRR = 1.13; 95% CI: 0.97-1.32) and significantly higher for belted drivers (MRR = 1.21; 95% CI: 1.04-1.39). Advanced air bag features appeared protective for some occupants. However, increased mortality rates among belted drivers of vehicles having certified-advanced air bags relative to those having sled-certified air bags with advanced features suggest that further study is needed to identify any potential problems with requirements for certification. 2010 Elsevier Inc. All rights reserved.

The design of electric vehicle intelligent charger

NASA Astrophysics Data System (ADS)

Xu, Yangyang; Wang, Ying

2018-05-01

As the situation of the lack of energy and environment pollution deteriorates rapidly, electric vehicle, a new type of traffic tool, is being researched worldwide. As the core components of electric vehicle, the battery and charger's performance play an important roles in the quality of electric vehicle. So the design of the Electric Vehicle Intelligent Charger based on language-C is designed in this paper. The hardware system is used to produce the input signals of Electric Vehicle Intelligent Charger. The software system adopts the language-C software as development environment. The design can accomplish the test of the parametric such as voltage-current and temperature.

Design of Launch Vehicle Flight Control Systems Using Ascent Vehicle Stability Analysis Tool

NASA Technical Reports Server (NTRS)

Jang, Jiann-Woei; Alaniz, Abran; Hall, Robert; Bedossian, Nazareth; Hall, Charles; Jackson, Mark

2011-01-01

A launch vehicle represents a complicated flex-body structural environment for flight control system design. The Ascent-vehicle Stability Analysis Tool (ASAT) is developed to address the complicity in design and analysis of a launch vehicle. The design objective for the flight control system of a launch vehicle is to best follow guidance commands while robustly maintaining system stability. A constrained optimization approach takes the advantage of modern computational control techniques to simultaneously design multiple control systems in compliance with required design specs. "Tower Clearance" and "Load Relief" designs have been achieved for liftoff and max dynamic pressure flight regions, respectively, in the presence of large wind disturbances. The robustness of the flight control system designs has been verified in the frequency domain Monte Carlo analysis using ASAT.

Remote Sensing of Battlefield Weather Conditions Using Unmanned Air Vehicles

DTIC Science & Technology

1982-09-01

November 1981 - 1 September 1982 September 1982 DTIC S•’ ELECTE FEB 1 o1983 AIR FORCE GEMPHYSICS LABORATORY j AIR FORCE SYSTEMS COMMAND UNITED STATES AIR...1982 AIR VEHICLES 6. PERFORMING ORG, REPORT NUMBER 7. AUTHOR(@) 8 a. CONTRACT OR GRANT NUMBER(a) Maynard L. Hill Contributors: E. Lucero, J . Rowland...of MQM107A BWOFS Mission ........... . . . 27 Table 3 Roller-coaster Mission Analysis Summary . . . . . . . . . . . . . 30 J Table 4 Metfly Mission

Collaborative Multidisciplinary Sciences for Analysis and Design of Aerospace Vehicles. Volume 1

DTIC Science & Technology

2017-05-01

AEROSPACE VEHICLES Volume 1 5a. CONTRACT NUMBER FA8650-09-2-3938 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62201F 6. AUTHOR(S) Raymond M...S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBERDesign and Analysis Branch (AFRL/RQVC) Aerospace Vehicles Division Air Force Research...Laboratory, Aerospace Systems Directorate Wright-Patterson Air Force Base, OH 45433-7542 Air Force Materiel Command, United States Air Force Virginia

Survivability design for a hybrid underwater vehicle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Biao; Wu, Chao; Li, Xiang

A novel hybrid underwater robotic vehicle (HROV) capable of working to the full ocean depth has been developed. The battery powered vehicle operates in two modes: operate as an untethered autonomous vehicle in autonomous underwater vehicle (AUV) mode and operate under remote control connected to the surface vessel by a lightweight, fiber optic tether in remotely operated vehicle (ROV) mode. Considering the hazardous underwater environment at the limiting depth and the hybrid operating modes, survivability has been placed on an equal level with the other design attributes of the HROV since the beginning of the project. This paper reports themore » survivability design elements for the HROV including basic vehicle design of integrated navigation and integrated communication, emergency recovery strategy, distributed architecture, redundant bus, dual battery package, emergency jettison system and self-repairing control system.« less

Northwest passage: Trade route for large air cushion vehicles

NASA Technical Reports Server (NTRS)

Anderson, J. L.

1973-01-01

A conceptual vehicle and powerplant (10,000-ton) nuclear-powered air-cushion vehicle (ACV) that could open the Northwest Passage and other Arctic passages to commercial traffic is identified. The report contains a description of the conceptual vehicle, including the powerplant and operations, an assessment of technical feasibility, estimates of capital and operating costs, and identification of eligible cargo and markets. A comparison of the nuclear ACV freighter with nuclear container ships shows that for containerized or roll-on/roll-off cargo the ACV would provide greatly reduced transit time between North Atlantic and North Pacific ports at a competitive cost.

Man-Vehicle Systems Research Facility - Design and operating characteristics

NASA Technical Reports Server (NTRS)

Shiner, Robert J.; Sullivan, Barry T.

1992-01-01

This paper describes the full-mission flight simulation facility at the NASA Ames Research Center. The Man-Vehicle Systems Research Facility (MVSRF) supports aeronautical human factors research and consists of two full-mission flight simulators and an air-traffic-control simulator. The facility is used for a broad range of human factors research in both conventional and advanced aviation systems. The objectives of the research are to improve the understanding of the causes and effects of human errors in aviation operations, and to limit their occurrence. The facility is used to: (1) develop fundamental analytical expressions of the functional performance characteristics of aircraft flight crews; (2) formulate principles and design criteria for aviation environments; (3) evaluate the integration of subsystems in contemporary flight and air traffic control scenarios; and (4) develop training and simulation technologies.

Membrane wing aerodynamics for micro air vehicles

NASA Astrophysics Data System (ADS)

Lian, Yongsheng; Shyy, Wei; Viieru, Dragos; Zhang, Baoning

2003-10-01

The aerodynamic performance of a wing deteriorates considerably as the Reynolds number decreases from 10 6 to 10 4. In particular, flow separation can result in substantial change in effective airfoil shape and cause reduced aerodynamic performance. Lately, there has been growing interest in developing suitable techniques for sustained and robust flight of micro air vehicles (MAVs) with a wingspan of 15 cm or smaller, flight speed around 10 m/ s, and a corresponding Reynolds number of 10 4-10 5. This paper reviews the aerodynamics of membrane and corresponding rigid wings under the MAV flight conditions. The membrane wing is observed to yield desirable characteristics in delaying stall as well as adapting to the unsteady flight environment, which is intrinsic to the designated flight speed. Flow structures associated with the low Reynolds number and low aspect ratio wing, such as pressure distribution, separation bubble and tip vortex are reviewed. Structural dynamics in response to the surrounding flow field is presented to highlight the multiple time-scale phenomena. Based on the computational capabilities for treating moving boundary problems, wing shape optimization can be conducted in automated manners. To enhance the lift, the effect of endplates is evaluated. The proper orthogonal decomposition method is also discussed as an economic tool to describe the flow structure around a wing and to facilitate flow and vehicle control.

Air liquefaction and enrichment system propulsion in reusable launch vehicles

NASA Astrophysics Data System (ADS)

Bond, W. H.; Yi, A. C.

1994-07-01

A concept is shown for a fully reusable, Earth-to-orbit launch vehicle with horizontal takeoff and landing, employing an air-turborocket for low speed and a rocket for high-speed acceleration, both using liquid hydrogen for fuel. The turborocket employs a modified liquid air cycle to supply the oxidizer. The rocket uses 90% pure liquid oxygen as its oxidizer that is collected from the atmosphere, separated, and stored during operation of the turborocket from about Mach 2 to 5 or 6. The takeoff weight and the thrust required at takeoff are markedly reduced by collecting the rocket oxidizer in-flight. This article shows an approach and the corresponding technology needs for using air liquefaction and enrichment system propulsion in a single-stage-to-orbit (SSTO) vehicle. Reducing the trajectory altitude at the end of collection reduces the wing area and increases payload. The use of state-of-the-art materials, such as graphite polyimide, in a direct substitution for aluminum or aluminum-lithium alloy, is critical to meet the structure weight objective for SSTO. Configurations that utilize 'waverider' aerodynamics show great promise to reduce the vehicle weight.

Heat source reentry vehicle design study

NASA Technical Reports Server (NTRS)

Ryan, R. L.

1971-01-01

The design details are presented of a flight-type heat source reentry vehicle and heat exchanger compatible with the isotope Brayton power conversion system. The reference reentry vehicle and heat exchanger were modified, orbital and superorbital capability was assessed, and a complete set of detail design layout drawings were provided.

Automated mixed traffic vehicle design AMTV 2

NASA Technical Reports Server (NTRS)

Johnston, A. R.; Marks, R. A.; Cassell, P. L.

1982-01-01

The design of an improved and enclosed Automated Mixed Traffic Transit (AMTT) vehicle is described. AMTT is an innovative concept for low-speed tram-type transit in which suitable vehicles are equipped with sensors and controls to permit them to operate in an automated mode on existing road or walkway surfaces. The vehicle chassis and body design are presented in terms of sketches and photographs. The functional design of the sensing and control system is presented, and modifications which could be made to the baseline design for improved performance, in particular to incorporate a 20-mph capability, are also discussed. The vehicle system is described at the block-diagram-level of detail. Specifications and parameter values are given where available.

Open tube guideway for high speed air cushioned vehicles

NASA Technical Reports Server (NTRS)

Goering, R. S. (Inventor)

1974-01-01

This invention is a tubular shaped guideway for high-speed air-cushioned supported vehicles. The tubular guideway is split and separated such that the sides of the guideway are open. The upper portion of the tubular guideway is supported above the lower portion by truss-like structural members. The lower portion of the tubular guideway may be supported by the terrain over which the vehicle travels, on pedestals or some similar structure.

A Systems Engineering Approach in Providing Air Defense Support to Ground Combat Vehicle Maneuver Forces

DTIC Science & Technology

2015-03-01

Defense DODAF Department of Defense Architecture Framework DOE design of experiment EMMI energy , mass, material wealth, information FNF fire and... energy or blast power (depending on the type of projectile). Tank munitions have significant penetrative ability and can cause serious damage to...survivability of ground combat vehicles during ground force maneuver operations. The simulation results indicated that the presence of air defense

Looking north Beale Air Force Base, Perimeter Acquisition Vehicle ...

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

Looking north - Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

Experimental Methods to Characterize Nonlinear Vibration of Flapping Wing Micro Air Vehicles

DTIC Science & Technology

2007-03-01

EXPERIMENTAL METHODS TO CHARACTERIZE NONLINEAR VIBRATION OF FLAPPING WING MICRO AIR VEHICLES THESIS Adam P. Tobias, Captain, USAF...AFIT/GAE/ENY/07-M23 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio...author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government

A framework for the evaluation of air pollution caused by motor vehicles

NASA Astrophysics Data System (ADS)

Elawej, Khalifa A. K.

This research investigated the problem of air pollution caused by vehicles in the city of Tripoli, Libya. This also included the identification of the socioeconomic and institutional factors which have contributed to the increased severity of the air pollution problem. The issues addressed included legal, institutional and technical aspects. A descriptive method was applied in which a case study approach was adopted. Primary data were collected through personal interviews with responsible people in relevant institutions, including EGA, GTL and ATD, complemented by questionnaires and direct observations. The data collected from the interviews and questionnaires were analysed using Excel and SPSS software.Owing to the lack of data on vehicular emissions in the study area, an inventory of the annual vehicular emissions in the city was made through the application of COPERT.4 software which is widely used for calculating vehicular emissions. This inventory covered the period from 2005 to 2010. Laboratory Mobile was also used to measure the concentration of vehicular emissions in the city centre of Tripoli, and compared with the vehicular concentrations in Sheffield, UK, for the same period.A framework was developed and validated to evaluate the air pollution caused by vehicles in Tripoli. The findings from the research showed that there has been a dramatic increase in the quantity of vehicle emissions in the city, highlighting the extent of the problem. Some influencing factors which have made a significant contribution to the occurrence and increased severity of traffic air pollution in Tripoli include: the increase in the vehicle fleet, the quality and quantity of the fuel consumed, insufficient public transportation, a shortage of public awareness, and deficiencies in the relevant legislation. Obstacles facing the responsible institutions include a lack of capable and qualified staff, and a shortage of necessary equipment for monitoring and addressing traffic

Lifting Body Flight Vehicles

NASA Technical Reports Server (NTRS)

Barret, Chris

1998-01-01

NASA has a technology program in place to build the X-33 test vehicle and then the full sized Reusable Launch Vehicle, VentureStar. VentureStar is a Lifting Body (LB) flight vehicle which will carry our future payloads into orbit, and will do so at a much reduced cost. There were three design contenders for the new Reusable Launch Vehicle: a Winged Vehicle, a Vertical Lander, and the Lifting Body(LB). The LB design won the competition. A LB vehicle has no wings and derives its lift solely from the shape of its body, and has the unique advantages of superior volumetric efficiency, better aerodynamic efficiency at high angles-of-attack and hypersonic speeds, and reduced thermal protection system weight. Classically, in a ballistic vehicle, drag has been employed to control the level of deceleration in reentry. In the LB, lift enables the vehicle to decelerate at higher altitudes for the same velocity and defines the reentry corridor which includes a greater cross range. This paper outlines our LB heritage which was utilized in the design of the new Reusable Launch Vehicle, VentureStar. NASA and the U.S. Air Force have a rich heritage of LB vehicle design and flight experience. Eight LB's were built and over 225 LB test flights were conducted through 1975 in the initial LB Program. Three LB series were most significant in the advancement of today's LB technology: the M2-F; HL-1O; and X-24 series. The M2-F series was designed by NASA Ames Research Center, the HL-10 series by NASA Langley Research Center, and the X-24 series by the Air Force. LB vehicles are alive again today.

Preventing passenger vehicle occupant injuries by vehicle design--a historical perspective from IIHS.

PubMed

O'Neill, Brian

2009-04-01

Motor vehicle crashes result in some 1.2 million deaths and many more injuries worldwide each year and is one of the biggest public health problems facing societies today. This article reviews the history of, and future potential for, one important countermeasure-designing vehicles that reduce occupant deaths and injuries. For many years, people had urged automakers to add design features to reduce crash injuries, but it was not until the mid-1960s that the idea of pursuing vehicle countermeasures gained any significant momentum. In 1966, the U.S. Congress passed the National Traffic and Motor Vehicle Safety Act, requiring the government to issue a comprehensive set of vehicle safety standards. This was the first broad set of requirements issued anywhere in the world, and within a few years similar standards were adopted in Europe and Australia. Early vehicle safety standards specified a variety of safety designs resulting in cars being equipped with lap/shoulder belts, energy-absorbing steering columns, crash-resistant door locks, high-penetration-resistant windshields, etc. Later, the standards moved away from specifying particular design approaches and instead used crash tests and instrumented dummies to set limits on the potential for serious occupant injuries by crash mode. These newer standards paved the way for an approach that used the marketplace, in addition to government regulation, to improve vehicle safety designs-using crash tests and instrumented dummies to provide consumers with comparative safety ratings for new vehicles. The approach began in the late 1970s, when NHTSA started publishing injury measures from belted dummies in new passenger vehicles subjected to frontal barrier crash tests at speeds somewhat higher than specified in the corresponding regulation. This program became the world's first New Car Assessment Program (NCAP) and rated frontal crashworthiness by awarding stars (five stars being the best and one the worst) derived from head

Affordable Flight Demonstration of the GTX Air-Breathing SSTO Vehicle Concept

NASA Technical Reports Server (NTRS)

Krivanek, Thomas M.; Roche, Joseph M.; Riehl, John P.; Kosareo, Daniel N.

2003-01-01

The rocket based combined cycle (RBCC) powered single-stage-to-orbit (SSTO) reusable launch vehicle has the potential to significantly reduce the total cost per pound for orbital payload missions. To validate overall system performance, a flight demonstration must be performed. This paper presents an overview of the first phase of a flight demonstration program for the GTX SSTO vehicle concept. Phase 1 will validate the propulsion performance of the vehicle configuration over the supersonic and hypersonic air- breathing portions of the trajectory. The focus and goal of Phase 1 is to demonstrate the integration and performance of the propulsion system flowpath with the vehicle aerodynamics over the air-breathing trajectory. This demonstrator vehicle will have dual mode ramjetkcramjets, which include the inlet, combustor, and nozzle with geometrically scaled aerodynamic surface outer mold lines (OML) defining the forebody, boundary layer diverter, wings, and tail. The primary objective of this study is to demon- strate propulsion system performance and operability including the ram to scram transition, as well as to validate vehicle aerodynamics and propulsion airframe integration. To minimize overall risk and develop ment cost the effort will incorporate proven materials, use existing turbomachinery in the propellant delivery systems, launch from an existing unmanned remote launch facility, and use basic vehicle recovery techniques to minimize control and landing requirements. A second phase would demonstrate propulsion performance across all critical portions of a space launch trajectory (lift off through transition to all-rocket) integrated with flight-like vehicle systems.

Internal air flow analysis of a bladeless micro aerial vehicle hemisphere body using computational fluid dynamic

NASA Astrophysics Data System (ADS)

Othman, M. N. K.; Zuradzman, M. Razlan; Hazry, D.; Khairunizam, Wan; Shahriman, A. B.; Yaacob, S.; Ahmed, S. Faiz; Hussain, Abadalsalam T.

2014-12-01

This paper explain the analysis of internal air flow velocity of a bladeless vertical takeoff and landing (VTOL) Micro Aerial Vehicle (MAV) hemisphere body. In mechanical design, before produce a prototype model, several analyses should be done to ensure the product's effectiveness and efficiency. There are two types of analysis method can be done in mechanical design; mathematical modeling and computational fluid dynamic. In this analysis, I used computational fluid dynamic (CFD) by using SolidWorks Flow Simulation software. The idea came through to overcome the problem of ordinary quadrotor UAV which has larger size due to using four rotors and the propellers are exposed to environment. The bladeless MAV body is designed to protect all electronic parts, which means it can be used in rainy condition. It also has been made to increase the thrust produced by the ducted propeller compare to exposed propeller. From the analysis result, the air flow velocity at the ducted area increased to twice the inlet air. This means that the duct contribute to the increasing of air velocity.

Internal air flow analysis of a bladeless micro aerial vehicle hemisphere body using computational fluid dynamic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Othman, M. N. K., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Zuradzman, M. Razlan, E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my; Hazry, D., E-mail: najibkhir86@gmail.com, E-mail: zuradzman@unimap.edu.my, E-mail: hazry@unimap.edu.my, E-mail: khairunizam@unimap.edu.my, E-mail: shahriman@unimap.edu.my, E-mail: s.yaacob@unimap.edu.my, E-mail: syedfaiz@unimap.edu.my, E-mail: abadal@unimap.edu.my

2014-12-04

This paper explain the analysis of internal air flow velocity of a bladeless vertical takeoff and landing (VTOL) Micro Aerial Vehicle (MAV) hemisphere body. In mechanical design, before produce a prototype model, several analyses should be done to ensure the product's effectiveness and efficiency. There are two types of analysis method can be done in mechanical design; mathematical modeling and computational fluid dynamic. In this analysis, I used computational fluid dynamic (CFD) by using SolidWorks Flow Simulation software. The idea came through to overcome the problem of ordinary quadrotor UAV which has larger size due to using four rotors andmore » the propellers are exposed to environment. The bladeless MAV body is designed to protect all electronic parts, which means it can be used in rainy condition. It also has been made to increase the thrust produced by the ducted propeller compare to exposed propeller. From the analysis result, the air flow velocity at the ducted area increased to twice the inlet air. This means that the duct contribute to the increasing of air velocity.« less

Modeling of Air-to-Air Refueling for an Unmanned Aerial Vehicle

NASA Astrophysics Data System (ADS)

Spears, Brian Raul

Air-to-air refueling is important to the military for enabling aircraft to remain in the air for long periods of time, reducing the need for forward bases, and allowing aircraft to stay on mission for longer intervals. Although this has been available for traditional military aircraft for several decades, it has not been implemented for the use of Unmanned Aerial Vehicles (UAV). This thesis uses a panel method, VSAERO, to examine the effects that a large tanker aircraft will have on a small unmanned aerial vehicle during a refueling process. The primary cause of conditions behind the tanker aircraft is the wake generated by the wingtip vortices of the aircraft. The planes used for this analysis were an Airbus A320 as the tanker, and a General Atomic MQ-9 as the receiver. The techniques used were to examine literature on aerial refueling, and analyze the aerodynamic characteristics of the UAV. The most important properties that were examined were the rolling moment, pitching moment, and lift. These characteristics were used to determine the feasibility of the UAV being able to withstand the conditions behind the A320. Through the analysis of the MQ-9's aerodynamic characteristics when in ideal conditions, along with its maximum rolling moment, and those same characteristics when flying behind the tanker, it was determined that the MQ-9 would be able to maintain position behind an A320 in order to complete the aerial refueling process.

A parallel expert system for the control of a robotic air vehicle

NASA Technical Reports Server (NTRS)

Shakley, Donald; Lamont, Gary B.

1988-01-01

Expert systems can be used to govern the intelligent control of vehicles, for example the Robotic Air Vehicle (RAV). Due to the nature of the RAV system the associated expert system needs to perform in a demanding real-time environment. The use of a parallel processing capability to support the associated expert system's computational requirement is critical in this application. Thus, algorithms for parallel real-time expert systems must be designed, analyzed, and synthesized. The design process incorporates a consideration of the rule-set/face-set size along with representation issues. These issues are looked at in reference to information movement and various inference mechanisms. Also examined is the process involved with transporting the RAV expert system functions from the TI Explorer, where they are implemented in the Automated Reasoning Tool (ART), to the iPSC Hypercube, where the system is synthesized using Concurrent Common LISP (CCLISP). The transformation process for the ART to CCLISP conversion is described. The performance characteristics of the parallel implementation of these expert systems on the iPSC Hypercube are compared to the TI Explorer implementation.

Episodic air quality impacts of plug-in electric vehicles

NASA Astrophysics Data System (ADS)

Razeghi, Ghazal; Carreras-Sospedra, Marc; Brown, Tim; Brouwer, Jack; Dabdub, Donald; Samuelsen, Scott

2016-07-01

In this paper, the Spatially and Temporally Resolved Energy and Environment Tool (STREET) is used in conjunction with University of California Irvine - California Institute of Technology (UCI-CIT) atmospheric chemistry and transport model to assess the impact of deploying plug-in electric vehicles and integrating wind energy into the electricity grid on urban air quality. STREET is used to generate emissions profiles associated with transportation and power generation sectors for different future cases. These profiles are then used as inputs to UCI-CIT to assess the impact of each case on urban air quality. The results show an overall improvement in 8-h averaged ozone and 24-h averaged particulate matter concentrations in the South Coast Air Basin (SoCAB) with localized increases in some cases. The most significant reductions occur northeast of the region where baseline concentrations are highest (up to 6 ppb decrease in 8-h-averaged ozone and 6 μg/m3 decrease in 24-h-averaged PM2.5). The results also indicate that, without integration of wind energy into the electricity grid, the temporal vehicle charging profile has very little to no effect on urban air quality. With the addition of wind energy to the grid mix, improvement in air quality is observed while charging at off-peak hours compared to the business as usual scenario.

Design of a Helium Vapor Shroud for Liquid Hydrogen Fueling of an Unmanned Aerial Vehicle (UAV)

NASA Astrophysics Data System (ADS)

Cavender, K.; Evans, C.; Haney, J.; Leachman, J.

2017-12-01

Filling a vehicular liquid hydrogen fuel tank presents the potential for flammable mixtures due to oxygen concentration from liquid air condensation. Current liquid hydrogen tank designs utilize insulating paradigms such as aerogel/fiberglass materials, vacuum jackets, or inert gas purge systems to keep the outer surface from reaching the condensation temperature of air. This work examines the heat transfer at the refuelling connection of the tank to identify potential areas of condensation, as well as the surface temperature gradient. A shrouded inert gas purge was designed to minimize vehicle weight and refuelling time. The design of a shrouded inert gas purge system is presented to displace air preventing air condensation. The design investigates 3D printed materials for an inert gas shroud, as well as low-temperature sealing designs. Shroud designs and temperature profiles were measured and tested by running liquid nitrogen through the filling manifold. Materials for the inert gas shroud are discussed and experimental results are compared to analytical model predictions. Suggestions for future design improvements are made.

Predicting Air Quality at First Ingress into Vehicles Visiting the International Space Station.

PubMed

Romoser, Amelia A; Scully, Robert R; Limero, Thomas F; De Vera, Vanessa; Cheng, Patti F; Hand, Jennifer J; James, John T; Ryder, Valerie E

2017-02-01

NASA regularly performs ground-based offgas tests (OGTs), which allow prediction of accumulated volatile pollutant concentrations at first entry on orbit, on whole modules and vehicles scheduled to connect to the International Space Station (ISS). These data guide crew safety operations and allow for estimation of ISS air revitalization systems impact from additional pollutant load. Since volatiles released from vehicle, module, and payload materials can affect crew health and performance, prediction of first ingress air quality is important. To assess whether toxicological risk is typically over or underpredicted, OGT and first ingress samples from 10 vehicles and modules were compared. Samples were analyzed by gas chromatography and gas chromatography-mass spectrometry. The rate of pollutant accumulation was extrapolated over time. Ratios of analytical values and Spacecraft Maximum Allowable Concentrations were used to predict total toxicity values (T-values) at first entry. Results were also compared by compound. Frequently overpredicted was 2-butanone (9/10), whereas propanal (6/10) and ethanol (8/10) were typically underpredicted, but T-values were not substantially affected. Ingress sample collection delay (estimated by octafluoropropane introduced from ISS atmosphere) and T-value prediction accuracy correlated well (R2 = 0.9008), highlighting the importance of immediate air sample collection and accounting for ISS air dilution. Importantly, T-value predictions were conservative 70% of the time. Results also suggest that T-values can be normalized to octafluoropropane levels to adjust for ISS air dilution at first ingress. Finally, OGT and ingress sampling has allowed small leaks in vehicle fluid systems to be recognized and addressed.Romoser AA, Scully RR, Limero TF, De Vera V, Cheng PF, Hand JJ, James JT, Ryder VE. Predicting air quality at first ingress into vehicles visiting the International Space Station. Aerosp Med Hum Perform. 2017; 88(2):104-113.

Near-term hybrid vehicle program, phase 1. Appendix B: Design trade-off studies report. Volume 2: Supplement to design trade-off studies

NASA Technical Reports Server (NTRS)

1979-01-01

Results of studies leading to the preliminary design of a hybrid passenger vehicle which is projected to have the maximum potential for reducing petroleum consumption in the near term are presented. Heat engine/electric hybrid vehicle tradeoffs, assessment of battery power source, and weight and cost analysis of key components are among the topics covered. Performance of auxiliary equipment, such as power steering, power brakes, air conditioning, lighting and electrical accessories, heating and ventilation is discussed along with the selection of preferred passenger compartment heating procedure for the hybrid vehicle. Waste heat from the engine, thermal energy storage, and an auxiliary burner are among the approaches considered.

Aerodynamics for Revolutionary Air Vehicles

NASA Technical Reports Server (NTRS)

Sellers, William L., III; Singer, Bart A.; Leavitt, Laurence D.

2003-01-01

Aeronautics research has seriously declined partly because of the perception that it is a mature science and only incremental improvements are possible. Recent aeronautics roadmapping activities at NASA Langley paint a different picture of the future. Breakthroughs are still felt to be possible if we expand the current design space of today's vehicles and optimize the airspace and vehicles as a system. The paper describes some of the challenges that the aircraft and airline industry face. These challenges include political, technical and environmental issues. Examples of the opportunities and technologies that could provide a different vision for the future are discussed.

Integration of Advanced Concepts and Vehicles Into the Next Generation Air Transportation System. Volume 1; Introduction, Key Messages, and Vehicle Attributes

NASA Technical Reports Server (NTRS)

Zellweger, Andres; Resnick, Herbert; Stevens, Edward; Arkind, Kenneth; Cotton William B.

2010-01-01

path -- are just a few of the potential new operations in the future National Airspace System. To assess the impact of these new scenarios on overall national airspace operations, the Raytheon team used the capabilities of a suite of tools such as NASA's Airspace Concepts Evaluation System (ACES), the Flight Optimization System (FLOPS), FAA's Aviation Environmental Design Tool (AEDT), Intelligent Automations Kinematic Trajectory Generator (KTG) and the Aviation Safety Risk Model (ASRM). Detailed metroplex modeling, surface delay models for super heavy transports, prioritized routing and corridors for supersonics business jets, and VLJ demand models are some of the models developed by the Raytheon team to study the effect of operating these new vehicles in the future NAS. Using this suite of models, several trade studies were conducted to evaluate these effects in terms of delays, equity in access, safety, and the environment. Looking at the impact of each vehicle, a number of critical issues were identified. The Raytheon team concluded that strict compliance to NextGen's 4-dimensional trajectory (4DT) management will be required to accommodate these vehicles unique operations and increased number of flights in the future air space system. The next section provides a discussion of this and the other key findings from our study.

Vehicle height and posture control of the electronic air suspension system using the hybrid system approach

NASA Astrophysics Data System (ADS)

Sun, Xiaoqiang; Cai, Yingfeng; Chen, Long; Liu, Yanling; Wang, Shaohua

2016-03-01

The electronic air suspension (EAS) system can improve ride comfort, fuel economy and handling safety of vehicles by adjusting vehicle height. This paper describes the development of a novel controller using the hybrid system approach to adjust the vehicle height (height control) and to regulate the roll and pitch angles of the vehicle body during the height adjustment process (posture control). The vehicle height adjustment system of EAS poses challenging hybrid control problems, since it features different discrete modes of operation, where each mode has an associated linear continuous-time dynamic. In this paper, we propose a novel approach to the modelling and controller design problem for the vehicle height adjustment system of EAS. The system model is described firstly in the hybrid system description language (HYSDEL) to obtain a mixed logical dynamical (MLD) hybrid model. For the resulting model, a hybrid model predictive controller is tuned to improve the vehicle height and posture tracking accuracy and to achieve the on-off statuses direct control of solenoid valves. The effectiveness and performance of the proposed approach are demonstrated by simulations and actual vehicle tests.

Optimization methods applied to hybrid vehicle design

NASA Technical Reports Server (NTRS)

Donoghue, J. F.; Burghart, J. H.

1983-01-01

The use of optimization methods as an effective design tool in the design of hybrid vehicle propulsion systems is demonstrated. Optimization techniques were used to select values for three design parameters (battery weight, heat engine power rating and power split between the two on-board energy sources) such that various measures of vehicle performance (acquisition cost, life cycle cost and petroleum consumption) were optimized. The apporach produced designs which were often significant improvements over hybrid designs already reported on in the literature. The principal conclusions are as follows. First, it was found that the strategy used to split the required power between the two on-board energy sources can have a significant effect on life cycle cost and petroleum consumption. Second, the optimization program should be constructed so that performance measures and design variables can be easily changed. Third, the vehicle simulation program has a significant effect on the computer run time of the overall optimization program; run time can be significantly reduced by proper design of the types of trips the vehicle takes in a one year period. Fourth, care must be taken in designing the cost and constraint expressions which are used in the optimization so that they are relatively smooth functions of the design variables. Fifth, proper handling of constraints on battery weight and heat engine rating, variables which must be large enough to meet power demands, is particularly important for the success of an optimization study. Finally, the principal conclusion is that optimization methods provide a practical tool for carrying out the design of a hybrid vehicle propulsion system.

Transition to Low-GWP Alternatives in Passenger Vehicle Air Conditioners

EPA Pesticide Factsheets

This fact sheet provides current information on low global warming potential (GWP) alternatives in newly manufactured passenger vehicle air conditioners (ACs), in lieu of high-GWP hydrofluorocarbons (HFCs).

Lateral Stability of a Dynamic Ram Air Cushion Vehicle

DOT National Transportation Integrated Search

1974-08-01

The lateral stability derivatives of a dynamic ram air cushion vehicle in a rectangular guideway were measured using a ship model towing tank. Lift and pitching moment are also reported. The primary lateral derivatives are all stabilizing, with signi...

Dynamic Response Analysis of an Icosahedron Shaped Lighter Than Air Vehicle

DTIC Science & Technology

2015-03-26

Montgolfier brothers successfully achieved flight using a hot - air balloon . While this was not the first time a LTAV had been imagined, it was the...first time one had been successfully built and flown [3]. Hot - air balloons are able to stay afloat in the atmosphere by displacing a volume of air ...These possibilities have already been exploited by LTAVs using a lifting gas (hydrogen, helium, hot air ), but those vehicles require storage for the gas

Transportation vehicle energy intensities. A joint DOT/NASA reference paper. [energy consumption of air and ground vehicles

NASA Technical Reports Server (NTRS)

Mascy, A. C.; Paullin, R. L.

1974-01-01

A compilation of data on the energy consumption of air and ground vehicles is presented. The ratio BTU/ASM, British Thermal Units/Available Seat Mile, is used to express vehicle energy intensiveness, and related to the energy consumed directly in producing seat-mile or ton-mile productivity. Data is presented on passenger and freight vehicles which are in current use or which are about to enter service, and advanced vehicles which may be operational in the 1980's and beyond. For the advanced vehicles, an estimate is given of the date of initial operational service, and the performance characteristics. Other key considerations in interpreting energy intensiveness for a given mode are discussed, such as: load factors, operations, overhead energy consumption, and energy investments in new structure and equipment.

NASA advanced aeronautics design solar powered remotely piloted vehicle

NASA Technical Reports Server (NTRS)

Elario, David S.; Guillmette, Neal H.; Lind, Gregory S.; Webster, Jonathan D.; Ferreira, Michael J.; Konstantakis, George C.; Marshall, David L.; Windt, Cari L.

1991-01-01

Environmental problems such as the depletion of the ozone layer and air pollution demand a change in traditional means of propulsion that is sensitive to the ecology. Solar powered propulsion is a favorable alternative that is both ecologically harmless as well as cost effective. Integration of solar energy into designs ranging from futuristic vehicles to heating is beneficial to society. The design and construction of a Multi-Purpose Remotely Piloted Vehicle (MPRPV) seeks to verify the feasibility of utilizing solar propulsion as a primary fuel source. This task has been a year long effort by a group of ten students, divided into five teams, each dealing with different aspects of the design. The aircraft was designed to take-off, climb to the design altitude, fly in a sustained figure-eight flight path, and cruise for approximately one hour. This mission requires flight at Reynolds numbers between 150,000 and 200,000 and demands special considerations in the aerodynamic design in order to achieve flight in this regime. Optimal performance requires a light weight configuration with both structural integrity and maximum power availability. The structure design and choice of solar cells for the propulsion was governed by the weight, efficiency, and cost considerations. The final design is a MPRPV weighting 35 N which cruises 7 m/s at the design altitude of 50 m. The configuration includes a wing composed of balsa and foam NACA 6409 airfoil sections and carbon fiber spars, a tail of similar construction, and a truss structure fuselage. The propulsion system consists of 98 10 percent efficient solar cells donated by Mobil Solar, a NiCad battery for energy storage, and a folding propeller regulated by a lightweight and efficient control system. The airfoils and propeller chosen for the design were research and tested during the design process.

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

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

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

Winged cargo return vehicle. Volume 1: Conceptual design

NASA Technical Reports Server (NTRS)

1990-01-01

The Advanced Design Project (ADP) allows an opportunity for students to work in conjunction with NASA and other aerospace companies on NASA Advanced Design Projects. The following volumes represent the design report: Volume 1 Conceptual Design; Volume 2 Wind Tunnel Tests; Volume 3 Structural Analysis; and Volume 4 Water Tunnel Tests. The project chosen by the University of Minnesota in conjunction with NASA Marshall Space Flight Center for this year is a Cargo Return Vehicle (CRV) to support the Space Station Freedom. The vehicle is the third generation of vehicles to be built by NASA, the first two being the Apollo program, and the Space Shuttle program. The CRV is to work in conjunction with a personnel launch system (PLS) to further subdivide and specialize the vehicles that NASA will operate in the year 2000. The cargo return vehicle will carry payload to and from the Space Station Freedom (SSF).

Lunar NTR vehicle design and operations study

NASA Technical Reports Server (NTRS)

Hodge, John

1993-01-01

The results of a lunar nuclear thermal rocket (NTR) vehicle design and operations study are presented in text and graphic form. The objectives of the study were to evaluate the potential applications of a specific NTR design to past and current (First Lunar Outpost) mission profiles for piloted and cargo lunar missions, and to assess the applicability of utilizing lunar vehicle design concepts for Mars missions.

Vehicle expectations in air transportation for the year 2000

NASA Technical Reports Server (NTRS)

Hearth, D. P.

1980-01-01

This paper is intended to provide an overview of the air transportation system for the year 2000 in terms of vehicle expectations. Emphasis is placed on civil air transportation with the time period approached from the standpoint of evolutionary changes for the near term and also with the assumption of more revolutionary changes for the far term. The view along the evolutionary path begins with a historical review of airline market growth and the impact that technologies have had on airplane designs. Projections of the life expectancy of existing, derivative, and new airplanes are examined in terms of their productivity and fuel efficiency in view of the present and projected fuel usage and availability. The factors influencing airline growth are outlined and some views on whether another new generation of subsonic airplanes are in the offing are given along with an assessment of the economic viability of an advanced commercial supersonic transport in terms of its higher speed, higher productivity, and higher fuel usage. With regard to revolutionary changes, major technology breakthroughs are assumed to occur at a specified date. As an example, the impact of a dramatic reduction in skin friction drag is examined in terms of its effect on the airplane configuration, its propulsion systems, it projected fuel usage, and the air transportation system in which it must operate.

Distributed pheromone-based swarming control of unmanned air and ground vehicles for RSTA

NASA Astrophysics Data System (ADS)

Sauter, John A.; Mathews, Robert S.; Yinger, Andrew; Robinson, Joshua S.; Moody, John; Riddle, Stephanie

2008-04-01

The use of unmanned vehicles in Reconnaissance, Surveillance, and Target Acquisition (RSTA) applications has received considerable attention recently. Cooperating land and air vehicles can support multiple sensor modalities providing pervasive and ubiquitous broad area sensor coverage. However coordination of multiple air and land vehicles serving different mission objectives in a dynamic and complex environment is a challenging problem. Swarm intelligence algorithms, inspired by the mechanisms used in natural systems to coordinate the activities of many entities provide a promising alternative to traditional command and control approaches. This paper describes recent advances in a fully distributed digital pheromone algorithm that has demonstrated its effectiveness in managing the complexity of swarming unmanned systems. The results of a recent demonstration at NASA's Wallops Island of multiple Aerosonde Unmanned Air Vehicles (UAVs) and Pioneer Unmanned Ground Vehicles (UGVs) cooperating in a coordinated RSTA application are discussed. The vehicles were autonomously controlled by the onboard digital pheromone responding to the needs of the automatic target recognition algorithms. UAVs and UGVs controlled by the same pheromone algorithm self-organized to perform total area surveillance, automatic target detection, sensor cueing, and automatic target recognition with no central processing or control and minimal operator input. Complete autonomy adds several safety and fault tolerance requirements which were integrated into the basic pheromone framework. The adaptive algorithms demonstrated the ability to handle some unplanned hardware failures during the demonstration without any human intervention. The paper describes lessons learned and the next steps for this promising technology.

System safety engineering in the development of advanced surface transportation vehicles

NASA Technical Reports Server (NTRS)

Arnzen, H. E.

1971-01-01

Applications of system safety engineering to the development of advanced surface transportation vehicles are described. As a pertinent example, the paper describes a safety engineering efforts tailored to the particular design and test requirements of the Tracked Air Cushion Research Vehicle (TACRV). The test results obtained from this unique research vehicle provide significant design data directly applicable to the development of future tracked air cushion vehicles that will carry passengers in comfort and safety at speeds up to 300 miles per hour.

Influence of structural dynamics on vehicle design - Government view. [of aerospace vehicles

NASA Technical Reports Server (NTRS)

Kordes, E. E.

1977-01-01

Dynamic design considerations for aerospace vehicles are discussed, taking into account fixed wing aircraft, rotary wing aircraft, and launch, space, and reentry vehicles. It is pointed out that space vehicles have probably had the most significant design problems from the standpoint of structural dynamics, because their large lightweight structures are highly nonlinear. Examples of problems in the case of conventional aircraft include the flutter encountered by high performance military aircraft with external stores. A description is presented of a number of examples which illustrate the direction of present efforts for improving aircraft efficiency. Attention is given to the results of studies on the structural design concepts for the arrow-wing supersonic cruise aircraft configuration and a system study on low-wing-loading, short haul transports.

Wooden Spaceships: Human-Centered Vehicle Design for Space

NASA Technical Reports Server (NTRS)

Twyford, Evan

2009-01-01

Presentation will focus on creative human centered design solutions in relation to manned space vehicle design and development in the NASA culture. We will talk about design process, iterative prototyping, mockup building and user testing and evaluation. We will take an inside look at how new space vehicle concepts are developed and designed for real life exploration scenarios.

Life cycle air emissions impacts and ownership costs of light-duty vehicles using natural gas as a primary energy source.

PubMed

Luk, Jason M; Saville, Bradley A; MacLean, Heather L

2015-04-21

This paper aims to comprehensively distinguish among the merits of different vehicles using a common primary energy source. In this study, we consider compressed natural gas (CNG) use directly in conventional vehicles (CV) and hybrid electric vehicles (HEV), and natural gas-derived electricity (NG-e) use in plug-in battery electric vehicles (BEV). This study evaluates the incremental life cycle air emissions (climate change and human health) impacts and life cycle ownership costs of non-plug-in (CV and HEV) and plug-in light-duty vehicles. Replacing a gasoline CV with a CNG CV, or a CNG CV with a CNG HEV, can provide life cycle air emissions impact benefits without increasing ownership costs; however, the NG-e BEV will likely increase costs (90% confidence interval: $1000 to $31 000 incremental cost per vehicle lifetime). Furthermore, eliminating HEV tailpipe emissions via plug-in vehicles has an insignificant incremental benefit, due to high uncertainties, with emissions cost benefits between -$1000 and $2000. Vehicle criteria air contaminants are a relatively minor contributor to life cycle air emissions impacts because of strict vehicle emissions standards. Therefore, policies should focus on adoption of plug-in vehicles in nonattainment regions, because CNG vehicles are likely more cost-effective at providing overall life cycle air emissions impact benefits.

Improving Conceptual Design for Launch Vehicles

NASA Technical Reports Server (NTRS)

Olds, John R.

1998-01-01

This report summarizes activities performed during the second year of a three year cooperative agreement between NASA - Langley Research Center and Georgia Tech. Year 1 of the project resulted in the creation of a new Cost and Business Assessment Model (CABAM) for estimating the economic performance of advanced reusable launch vehicles including non-recurring costs, recurring costs, and revenue. The current year (second year) activities were focused on the evaluation of automated, collaborative design frameworks (computation architectures or computational frameworks) for automating the design process in advanced space vehicle design. Consistent with NASA's new thrust area in developing and understanding Intelligent Synthesis Environments (ISE), the goals of this year's research efforts were to develop and apply computer integration techniques and near-term computational frameworks for conducting advanced space vehicle design. NASA - Langley (VAB) has taken a lead role in developing a web-based computing architectures within which the designer can interact with disciplinary analysis tools through a flexible web interface. The advantages of this approach are, 1) flexible access to the designer interface through a simple web browser (e.g. Netscape Navigator), 2) ability to include existing 'legacy' codes, and 3) ability to include distributed analysis tools running on remote computers. To date, VAB's internal emphasis has been on developing this test system for the planetary entry mission under the joint Integrated Design System (IDS) program with NASA - Ames and JPL. Georgia Tech's complementary goals this year were to: 1) Examine an alternate 'custom' computational architecture for the three-discipline IDS planetary entry problem to assess the advantages and disadvantages relative to the web-based approach.and 2) Develop and examine a web-based interface and framework for a typical launch vehicle design problem.

Euler Calculations at Off-Design Conditions for an Inlet of Inward Turning RBCC-SSTO Vehicle

NASA Technical Reports Server (NTRS)

Takashima, N.; Kothari, A. P.

1998-01-01

The inviscid performance of an inward turning inlet design is calculated computationally for the first time. Hypersonic vehicle designs based on the inward turning inlets have been shown analytically to have increased effective specific impulse and lower heat load than comparably designed vehicles with two-dimensional inlets. The inward turning inlets are designed inversely from inviscid stream surfaces of known flow fields. The computational study is performed on a Mach 12 inlet design to validate the performance predicted by the design code (HAVDAC) and calculate its off-design Mach number performance. The three-dimensional Euler equations are solved for Mach 4, 8, and 12 using a software package called SAM, which consists of an unstructured mesh generator (SAMmesh), a three-dimensional unstructured mesh flow solver (SAMcfd), and a CAD-based software (SAMcad). The computed momentum averaged inlet throat pressure is within 6% of the design inlet throat pressure. The mass-flux at the inlet throat is also within 7 % of the value predicted by the design code thereby validating the accuracy of the design code. The off-design Mach number results show that flow spillage is minimal, and the variation in the mass capture ratio with Mach number is comparable to an ideal 2-D inlet. The results from the inviscid flow calculations of a Mach 12 inward turning inlet indicate that the inlet design has very good on and off-design performance which makes it a promising design candidate for future air-breathing hypersonic vehicles.

Wind machines. [aerodynamics of sailwing vehicles

NASA Technical Reports Server (NTRS)

Lissaman, P. B. S.

1973-01-01

The basic elements of the air/water momentum exchange are described by the environment, the potential, the air and water subsystems, the total system, and the rule. Many of these topics have direct analogues in aerogenerator design. Aspects of optimal sail design and of waveless hulls are briefly outlined. A wind driven vehicle capable of moving directly downwind faster than the wind, is reported. The lecture is illustrated with slides and movie clips showing surfing catamarans, land and water versions of the Bauer vehicle, hang gliding, land sailing, and wind surfing.

Model Update of a Micro Air Vehicle (MAV) Flexible Wing Frame with Uncertainty Quantification

NASA Technical Reports Server (NTRS)

Reaves, Mercedes C.; Horta, Lucas G.; Waszak, Martin R.; Morgan, Benjamin G.

2004-01-01

This paper describes a procedure to update parameters in the finite element model of a Micro Air Vehicle (MAV) to improve displacement predictions under aerodynamics loads. Because of fabrication, materials, and geometric uncertainties, a statistical approach combined with Multidisciplinary Design Optimization (MDO) is used to modify key model parameters. Static test data collected using photogrammetry are used to correlate with model predictions. Results show significant improvements in model predictions after parameters are updated; however, computed probabilities values indicate low confidence in updated values and/or model structure errors. Lessons learned in the areas of wing design, test procedures, modeling approaches with geometric nonlinearities, and uncertainties quantification are all documented.

Valuation of plug-in vehicle life-cycle air emissions and oil displacement benefits

PubMed Central

Michalek, Jeremy J.; Chester, Mikhail; Jaramillo, Paulina; Samaras, Constantine; Shiau, Ching-Shin Norman; Lave, Lester B.

2011-01-01

We assess the economic value of life-cycle air emissions and oil consumption from conventional vehicles, hybrid-electric vehicles (HEVs), plug-in hybrid-electric vehicles (PHEVs), and battery electric vehicles in the US. We find that plug-in vehicles may reduce or increase externality costs relative to grid-independent HEVs, depending largely on greenhouse gas and SO2 emissions produced during vehicle charging and battery manufacturing. However, even if future marginal damages from emissions of battery and electricity production drop dramatically, the damage reduction potential of plug-in vehicles remains small compared to ownership cost. As such, to offer a socially efficient approach to emissions and oil consumption reduction, lifetime cost of plug-in vehicles must be competitive with HEVs. Current subsidies intended to encourage sales of plug-in vehicles with large capacity battery packs exceed our externality estimates considerably, and taxes that optimally correct for externality damages would not close the gap in ownership cost. In contrast, HEVs and PHEVs with small battery packs reduce externality damages at low (or no) additional cost over their lifetime. Although large battery packs allow vehicles to travel longer distances using electricity instead of gasoline, large packs are more expensive, heavier, and more emissions intensive to produce, with lower utilization factors, greater charging infrastructure requirements, and life-cycle implications that are more sensitive to uncertain, time-sensitive, and location-specific factors. To reduce air emission and oil dependency impacts from passenger vehicles, strategies to promote adoption of HEVs and PHEVs with small battery packs offer more social benefits per dollar spent. PMID:21949359

Valuation of plug-in vehicle life-cycle air emissions and oil displacement benefits.

PubMed

Michalek, Jeremy J; Chester, Mikhail; Jaramillo, Paulina; Samaras, Constantine; Shiau, Ching-Shin Norman; Lave, Lester B

2011-10-04

We assess the economic value of life-cycle air emissions and oil consumption from conventional vehicles, hybrid-electric vehicles (HEVs), plug-in hybrid-electric vehicles (PHEVs), and battery electric vehicles in the US. We find that plug-in vehicles may reduce or increase externality costs relative to grid-independent HEVs, depending largely on greenhouse gas and SO(2) emissions produced during vehicle charging and battery manufacturing. However, even if future marginal damages from emissions of battery and electricity production drop dramatically, the damage reduction potential of plug-in vehicles remains small compared to ownership cost. As such, to offer a socially efficient approach to emissions and oil consumption reduction, lifetime cost of plug-in vehicles must be competitive with HEVs. Current subsidies intended to encourage sales of plug-in vehicles with large capacity battery packs exceed our externality estimates considerably, and taxes that optimally correct for externality damages would not close the gap in ownership cost. In contrast, HEVs and PHEVs with small battery packs reduce externality damages at low (or no) additional cost over their lifetime. Although large battery packs allow vehicles to travel longer distances using electricity instead of gasoline, large packs are more expensive, heavier, and more emissions intensive to produce, with lower utilization factors, greater charging infrastructure requirements, and life-cycle implications that are more sensitive to uncertain, time-sensitive, and location-specific factors. To reduce air emission and oil dependency impacts from passenger vehicles, strategies to promote adoption of HEVs and PHEVs with small battery packs offer more social benefits per dollar spent.

Potential impacts of electric vehicles on air quality in Taiwan.

PubMed

Li, Nan; Chen, Jen-Ping; Tsai, I-Chun; He, Qingyang; Chi, Szu-Yu; Lin, Yi-Chiu; Fu, Tzung-May

2016-10-01

The prospective impacts of electric vehicle (EV) penetration on the air quality in Taiwan were evaluated using an air quality model with the assumption of an ambitious replacement of current light-duty vehicles under different power generation scenarios. With full EV penetration (i.e., the replacement of all light-duty vehicles), CO, VOCs, NOx and PM2.5 emissions in Taiwan from a fleet of 20.6 million vehicles would be reduced by 1500, 165, 33.9 and 7.2Ggyr(-1), respectively, while electric sector NOx and SO2 emissions would be increased by up to 20.3 and 12.9Ggyr(-1), respectively, if the electricity to power EVs were provided by thermal power plants. The net impacts of these emission changes would be to reduce the annual mean surface concentrations of CO, VOCs, NOx and PM2.5 by about 260, 11.3, 3.3ppb and 2.1μgm(-3), respectively, but to increase SO2 by 0.1ppb. Larger reductions tend to occur at time and place of higher ambient concentrations and during high pollution events. Greater benefits would clearly be attained if clean energy sources were fully encouraged. EV penetration would also reduce the mean peak-time surface O3 concentrations by up to 7ppb across Taiwan with the exception of the center of metropolitan Taipei where the concentration increased by <2ppb. Furthermore, full EV penetration would reduce annual days of O3 pollution episodes by ~40% and PM2.5 pollution episodes by 6-10%. Our findings offer important insights into the air quality impacts of EV and can provide useful information for potential mitigation actions. Copyright © 2016 Elsevier B.V. All rights reserved.

Integrated Design and Engineering Analysis (IDEA) Environment - Propulsion Related Module Development and Vehicle Integration

NASA Technical Reports Server (NTRS)

Kamhawi, Hilmi N.

2013-01-01

This report documents the work performed during the period from May 2011 - October 2012 on the Integrated Design and Engineering Analysis (IDEA) environment. IDEA is a collaborative environment based on an object-oriented, multidisciplinary, distributed framework using the Adaptive Modeling Language (AML). This report will focus on describing the work done in the areas of: (1) Integrating propulsion data (turbines, rockets, and scramjets) in the system, and using the data to perform trajectory analysis; (2) Developing a parametric packaging strategy for a hypersonic air breathing vehicles allowing for tank resizing when multiple fuels and/or oxidizer are part of the configuration; and (3) Vehicle scaling and closure strategies.

Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix

NASA Technical Reports Server (NTRS)

Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

1999-01-01

This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being studied at Langley; it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission flexibility restraints.

Airbreathing Hypersonic Vision-Operational-Vehicles Design Matrix

NASA Technical Reports Server (NTRS)

Hunt, James L.; Pegg, Robert J.; Petley, Dennis H.

1999-01-01

This paper presents the status of the airbreathing hypersonic airplane and space-access vision-operational-vehicle design matrix, with emphasis on horizontal takeoff and landing systems being, studied at Langley, it reflects the synergies and issues, and indicates the thrust of the effort to resolve the design matrix including Mach 5 to 10 airplanes with global-reach potential, pop-up and dual-role transatmospheric vehicles and airbreathing launch systems. The convergence of several critical systems/technologies across the vehicle matrix is indicated. This is particularly true for the low speed propulsion system for large unassisted horizontal takeoff vehicles which favor turbines and/or perhaps pulse detonation engines that do not require LOX which imposes loading concerns and mission Flexibility restraints.

Rehabilitation of the Rocket Vehicle Integration Test Stand at Edwards Air Force Base

NASA Technical Reports Server (NTRS)

Jones, Daniel S.; Ray, Ronald J.; Phillips, Paul

2005-01-01

Since initial use in 1958 for the X-15 rocket-powered research airplane, the Rocket Engine Test Facility has proven essential for testing and servicing rocket-powered vehicles at Edwards Air Force Base. For almost two decades, several successful flight-test programs utilized the capability of this facility. The Department of Defense has recently demonstrated a renewed interest in propulsion technology development with the establishment of the National Aerospace Initiative. More recently, the National Aeronautics and Space Administration is undergoing a transformation to realign the organization, focusing on the Vision for Space Exploration. These initiatives provide a clear indication that a very capable ground-test stand at Edwards Air Force Base will be beneficial to support the testing of future access-to-space vehicles. To meet the demand of full integration testing of rocket-powered vehicles, the NASA Dryden Flight Research Center, the Air Force Flight Test Center, and the Air Force Research Laboratory have combined their resources in an effort to restore and upgrade the original X-15 Rocket Engine Test Facility to become the new Rocket Vehicle Integration Test Stand. This report describes the history of the X-15 Rocket Engine Test Facility, discusses the current status of the facility, and summarizes recent efforts to rehabilitate the facility to support potential access-to-space flight-test programs. A summary of the capabilities of the facility is presented and other important issues are discussed.

Sliding mode disturbance observer-enhanced adaptive control for the air-breathing hypersonic flight vehicle

NASA Astrophysics Data System (ADS)

An, Hao; Wang, Changhong; Fidan, Baris

2017-10-01

This paper presents a backstepping procedure to design an adaptive controller for the air-breathing hypersonic flight vehicle (AHFV) subject to external disturbances and actuator saturations. In each step, a sliding mode exact disturbance observer (SMEDO) is exploited to exactly estimate the lumped disturbance in finite time. Specific dynamics are introduced to handle the possible actuator saturations. Based on SMEDO and introduced dynamics, an adaptive control law is designed, along with the consideration on ;explosion of complexity; in backstepping design. The developed controller is equipped with fast disturbance rejection and great capability to accommodate the saturated actuators, which also lead to a wider application scope. A simulation study is provided to show the effectiveness and superiority of the proposed controller.

Design and Performance of Insect-Scale Flapping-Wing Vehicles

NASA Astrophysics Data System (ADS)

Whitney, John Peter

Micro-air vehicles (MAVs)---small versions of full-scale aircraft---are the product of a continued path of miniaturization which extends across many fields of engineering. Increasingly, MAVs approach the scale of small birds, and most recently, their sizes have dipped into the realm of hummingbirds and flying insects. However, these non-traditional biologically-inspired designs are without well-established design methods, and manufacturing complex devices at these tiny scales is not feasible using conventional manufacturing methods. This thesis presents a comprehensive investigation of new MAV design and manufacturing methods, as applicable to insect-scale hovering flight. New design methods combine an energy-based accounting of propulsion and aerodynamics with a one degree-of-freedom dynamic flapping model. Important results include analytical expressions for maximum flight endurance and range, and predictions for maximum feasible wing size and body mass. To meet manufacturing constraints, the use of passive wing dynamics to simplify vehicle design and control was investigated; supporting tests included the first synchronized measurements of real-time forces and three-dimensional kinematics generated by insect-scale flapping wings. These experimental methods were then expanded to study optimal wing shapes and high-efficiency flapping kinematics. To support the development of high-fidelity test devices and fully-functional flight hardware, a new class of manufacturing methods was developed, combining elements of rigid-flex printed circuit board fabrication with "pop-up book" folding mechanisms. In addition to their current and future support of insect-scale MAV development, these new manufacturing techniques are likely to prove an essential element to future advances in micro-optomechanics, micro-surgery, and many other fields.

Fugitive particulate air emissions from off-road vehicle maneuvers at military training lands

USDA-ARS?s Scientific Manuscript database

Military training lands used for off-road vehicle maneuvers may be subject to severe soil loss and air quality degradation as a result of severe wind erosion. The objective of this study was to measure suspended particulate matter resulting from various different vehicle training scenarios. Soil s...

Design study of toroidal traction CVT for electric vehicles

NASA Technical Reports Server (NTRS)

Raynard, A. E.; Kraus, J.; Bell, D. D.

1980-01-01

The development, evaluation, and optimization of a preliminary design concept for a continuously variable transmission (CVT) to couple the high-speed output shaft of an energy storage flywheel to the drive train of an electric vehicle is discussed. An existing computer simulation program was modified and used to compare the performance of five CVT design configurations. Based on this analysis, a dual-cavity full-toroidal drive with regenerative gearing is selected for the CVT design configuration. Three areas are identified that will require some technological development: the ratio control system, the traction fluid properities, and evaluation of the traction contact performance. Finally, the suitability of the selected CVT design concept for alternate electric and hybrid vehicle applications and alternate vehicle sizes and maximum output torques is determined. In all cases the toroidal traction drive design concept is applicable to the vehicle system. The regenerative gearing could be eliminated in the electric powered vehicle because of the reduced ratio range requirements. In other cases the CVT with regenerative gearing would meet the design requirements after appropriate adjustments in size and reduction gearing ratio.

Biconic cargo return vehicle with an advanced recovery system. Volume 1: Conceptual design

NASA Technical Reports Server (NTRS)

1990-01-01

The conceptual design of the biconic Cargo Return Vehicle (CRV) is presented. The CRV will be able to meet all of the Space Station Freedom (SSF's) resupply needs. Worth note is the absence of a backup recovery chute in case of Advanced Recovery System (ARS) failure. The high reliability of ram-air parachutes does not warrant the penalty weight that such a system would create on successful missions. The CRV will launch vertically integrated with an Liquid Rocket Booster (LRB) vehicle and meets all NASA restrictions on fuel type for all phases of the mission. Because of the downscaled Orbital Maneuvering Vehicle (OMV) program, the CRV has been designed to be able to transfer cargo by docking directly to the Space Station Freedom as well as with OMV assistance. The CRV will cover enough crossrange to reach its primary landing site, Edwards Airforce Base, and all secondary landing sites with the exception of one orbit. Transportation back to KSC will be via the Boeing Super Guppy. Due to difficulties with man-rating the CRV, it will not be used in a CERV role. A brief summary of the CRV's specifications is given.

Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Electric Substation, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

X-45A Air Vehicle #1 during flight #13, with weapons bay door open

NASA Image and Video Library

2003-02-21

The DARPA/U.S. Air Force X-45A Unmanned Combat Air Vehicle (UCAV) system demonstration program completed the first phase of demonstrations, known as Block I, on Feb. 28, 2003. The final Block I activities included two flights at Dryden, during which safe operation of the weapons bay door was verified at 35,000 feet and speeds of Mach 0.75, the maximum planned altitude and speed for the two X-45A demonstrator vehicles.

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).

Code of Federal Regulations, 2012 CFR

2012-01-01

..., rail, air and marine). 3.114 Section 3.114 Animals and Animal Products ANIMAL AND PLANT HEALTH... conveyances (motor vehicle, rail, air and marine). (a) The animal cargo space of primary conveyances used in.... (e) The interiors of animal cargo spaces in primary conveyances must be kept clean. (f) Live marine...

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).

Code of Federal Regulations, 2010 CFR

2010-01-01

..., rail, air and marine). 3.114 Section 3.114 Animals and Animal Products ANIMAL AND PLANT HEALTH... conveyances (motor vehicle, rail, air and marine). (a) The animal cargo space of primary conveyances used in.... (e) The interiors of animal cargo spaces in primary conveyances must be kept clean. (f) Live marine...

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).

Code of Federal Regulations, 2013 CFR

2013-01-01

..., rail, air and marine). 3.114 Section 3.114 Animals and Animal Products ANIMAL AND PLANT HEALTH... conveyances (motor vehicle, rail, air and marine). (a) The animal cargo space of primary conveyances used in.... (e) The interiors of animal cargo spaces in primary conveyances must be kept clean. (f) Live marine...

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).

Code of Federal Regulations, 2014 CFR

2014-01-01

..., rail, air and marine). 3.114 Section 3.114 Animals and Animal Products ANIMAL AND PLANT HEALTH... conveyances (motor vehicle, rail, air and marine). (a) The animal cargo space of primary conveyances used in.... (e) The interiors of animal cargo spaces in primary conveyances must be kept clean. (f) Live marine...

9 CFR 3.114 - Primary conveyances (motor vehicle, rail, air and marine).

Code of Federal Regulations, 2011 CFR

2011-01-01

..., rail, air and marine). 3.114 Section 3.114 Animals and Animal Products ANIMAL AND PLANT HEALTH... conveyances (motor vehicle, rail, air and marine). (a) The animal cargo space of primary conveyances used in.... (e) The interiors of animal cargo spaces in primary conveyances must be kept clean. (f) Live marine...

Crash scene photography in motor vehicle crashes without air bag deployment.

PubMed

Newgard, Craig D; Martens, Katherine A; Lyons, Evelyn M

2002-09-01

To determine whether vehicle characteristics, measured using crash scene photography, are associated with anatomic patterns of injury and severity of injury sustained in motor vehicle crashes (MVCs) without air bag deployment. A prospective observational study was conducted over 22 months, using 12 fire departments serving two hospitals. Two vehicle photographs (exterior and interior) were taken at each MVC. Vehicular variables were assigned by grading the photographs with a standardized scoring system, and outcome information on each patient was collected by chart review. Five hundred fifty-nine patients were entered into the study. Frontal crashes and increasing passenger space intrusion (PSI) were associated with head, facial, and lower-extremity injuries, while rear crashes were associated with spinal injuries. Restraint use had a protective effect in head, facial, and upper and lower extremity injuries, yet was associated with higher odds of spinal injury. Lack of restraint use, increasing PSI, and steering wheel deformity were associated with an increased hospital length of stay and hospital charges, yet only steering wheel deformity was associated with increasing injury severity when adjusting for other crash variables. Out-of-hospital variables, as obtained from crash vehicle photography, are associated with injury site, injury severity, hospital length of stay, and hospital charges in patients involved in MVCs without air bag deployment.

Launch Vehicle Design Process Characterization Enables Design/Project Tool

NASA Technical Reports Server (NTRS)

Blair, J. C.; Ryan, R. S.; Schutzenhofer, L. A.; Robinson, Nancy (Technical Monitor)

2001-01-01

The objectives of the project described in this viewgraph presentation included the following: (1) Provide an overview characterization of the launch vehicle design process; and (2) Delineate design/project tool to identify, document, and track pertinent data.

Teaching case studies on the regulation of motor vehicle air pollution in China.

DOT National Transportation Integrated Search

2009-12-23

Motor vehicle air pollution is a critical component of China's severe air quality problem and has the potential to become an even greater issue in the years to come. On this project, the principal investigator and research staff are developing Harvar...

Uncertainty analysis and robust trajectory linearization control of a flexible air-breathing hypersonic vehicle

NASA Astrophysics Data System (ADS)

Pu, Zhiqiang; Tan, Xiangmin; Fan, Guoliang; Yi, Jianqiang

2014-08-01

Flexible air-breathing hypersonic vehicles feature significant uncertainties which pose huge challenges to robust controller designs. In this paper, four major categories of uncertainties are analyzed, that is, uncertainties associated with flexible effects, aerodynamic parameter variations, external environmental disturbances, and control-oriented modeling errors. A uniform nonlinear uncertainty model is explored for the first three uncertainties which lumps all uncertainties together and consequently is beneficial for controller synthesis. The fourth uncertainty is additionally considered in stability analysis. Based on these analyses, the starting point of the control design is to decompose the vehicle dynamics into five functional subsystems. Then a robust trajectory linearization control (TLC) scheme consisting of five robust subsystem controllers is proposed. In each subsystem controller, TLC is combined with the extended state observer (ESO) technique for uncertainty compensation. The stability of the overall closed-loop system with the four aforementioned uncertainties and additional singular perturbations is analyzed. Particularly, the stability of nonlinear ESO is also discussed from a Liénard system perspective. At last, simulations demonstrate the great control performance and the uncertainty rejection ability of the robust scheme.

Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Satellite Communications Terminal, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

Transitioning to Low-GWP Alternatives in Motor Vehicle Air Conditioning Systems

EPA Pesticide Factsheets

This fact sheet provides information on low-GWP alternatives in newly manufactured motor vehicle air conditioning systems. It discusses HFC alternatives, market trends, challenges to market entry for alternatives, and potential solutions.

Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Microwave Equipment Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

In-vehicle exposures to particulate air pollution in Canadian metropolitan areas: the urban transportation exposure study.

PubMed

Weichenthal, Scott; Van Ryswyk, Keith; Kulka, Ryan; Sun, Liu; Wallace, Lance; Joseph, Lawrence

2015-01-06

Commuters may be exposed to increased levels of traffic-related air pollution owing to close proximity to traffic-emissions. We collected in-vehicle and roof-top air pollution measurements over 238 commutes in Montreal, Toronto, and Vancouver, Canada between 2010 and 2013. Voice recordings were used to collect real-time information on traffic density and the presence of diesel vehicles and multivariable linear regression models were used to estimate the impact of these factors on in-vehicle pollutant concentrations (and indoor/outdoor ratios) along with parameters for road type, land use, and meteorology. In-vehicle PM2.5 and NO2 concentrations consistently exceeded regional outdoor levels and each unit increase in the rate of encountering diesel vehicles (count/min) was associated with substantial increases (>100%) in in-vehicle concentrations of ultrafine particles (UFPs), black carbon, and PM2.5 as well as strong increases (>15%) in indoor/outdoor ratios. A model based on meteorology and the length of highway roads within a 500 m buffer explained 53% of the variation in in-vehicle UFPs; however, models for PM2.5 (R(2) = 0.24) and black carbon (R(2) = 0.30) did not perform as well. Our findings suggest that vehicle commuters experience increased exposure to air pollutants and that traffic characteristics, land use, road types, and meteorology are important determinants of these exposures.

Beale Air Force Base, Perimeter Acquisition Vehicle Entry PhasedArray Warning ...

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

Beale Air Force Base, Perimeter Acquisition Vehicle Entry Phased-Array Warning System, Civil Engineering Storage Building, End of Spencer Paul Road, north of Warren Shingle Road (14th Street), Marysville, Yuba County, CA

Characterizing Epistemic Uncertainty for Launch Vehicle Designs

NASA Technical Reports Server (NTRS)

Novack, Steven D.; Rogers, Jim; Al Hassan, Mohammad; Hark, Frank

2016-01-01

NASA Probabilistic Risk Assessment (PRA) has the task of estimating the aleatory (randomness) and epistemic (lack of knowledge) uncertainty of launch vehicle loss of mission and crew risk, and communicating the results. Launch vehicles are complex engineered systems designed with sophisticated subsystems that are built to work together to accomplish mission success. Some of these systems or subsystems are in the form of heritage equipment, while some have never been previously launched. For these cases, characterizing the epistemic uncertainty is of foremost importance, and it is anticipated that the epistemic uncertainty of a modified launch vehicle design versus a design of well understood heritage equipment would be greater. For reasons that will be discussed, standard uncertainty propagation methods using Monte Carlo simulation produce counter intuitive results, and significantly underestimate epistemic uncertainty for launch vehicle models. Furthermore, standard PRA methods, such as Uncertainty-Importance analyses used to identify components that are significant contributors to uncertainty, are rendered obsolete, since sensitivity to uncertainty changes are not reflected in propagation of uncertainty using Monte Carlo methods. This paper provides a basis of the uncertainty underestimation for complex systems and especially, due to nuances of launch vehicle logic, for launch vehicles. It then suggests several alternative methods for estimating uncertainty and provides examples of estimation results. Lastly, the paper describes how to implement an Uncertainty-Importance analysis using one alternative approach, describes the results, and suggests ways to reduce epistemic uncertainty by focusing on additional data or testing of selected components.

Characterizing Epistemic Uncertainty for Launch Vehicle Designs

NASA Technical Reports Server (NTRS)

Novack, Steven D.; Rogers, Jim; Hark, Frank; Al Hassan, Mohammad

2016-01-01

NASA Probabilistic Risk Assessment (PRA) has the task of estimating the aleatory (randomness) and epistemic (lack of knowledge) uncertainty of launch vehicle loss of mission and crew risk and communicating the results. Launch vehicles are complex engineered systems designed with sophisticated subsystems that are built to work together to accomplish mission success. Some of these systems or subsystems are in the form of heritage equipment, while some have never been previously launched. For these cases, characterizing the epistemic uncertainty is of foremost importance, and it is anticipated that the epistemic uncertainty of a modified launch vehicle design versus a design of well understood heritage equipment would be greater. For reasons that will be discussed, standard uncertainty propagation methods using Monte Carlo simulation produce counter intuitive results and significantly underestimate epistemic uncertainty for launch vehicle models. Furthermore, standard PRA methods such as Uncertainty-Importance analyses used to identify components that are significant contributors to uncertainty are rendered obsolete since sensitivity to uncertainty changes are not reflected in propagation of uncertainty using Monte Carlo methods.This paper provides a basis of the uncertainty underestimation for complex systems and especially, due to nuances of launch vehicle logic, for launch vehicles. It then suggests several alternative methods for estimating uncertainty and provides examples of estimation results. Lastly, the paper shows how to implement an Uncertainty-Importance analysis using one alternative approach, describes the results, and suggests ways to reduce epistemic uncertainty by focusing on additional data or testing of selected components.

Series hybrid vehicles and optimized hydrogen engine design

NASA Astrophysics Data System (ADS)

Smith, J. R.; Aceves, S.; Vanblarigan, P.

1995-05-01

Lawrence Livermore, Sandia Livermore and Los Alamos National Laboratories have a joint project to develop an optimized hydrogen fueled engine for series hybrid automobiles. The major divisions of responsibility are: system analysis, engine design and kinetics modeling by LLNL; performance and emission testing, and friction reduction by SNL; computational fluid mechanics and combustion modeling by LANL. This project is a component of the Department of Energy, Office of Utility Technology, National Hydrogen Program. We report here on the progress on system analysis and preliminary engine testing. We have done system studies of series hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. The impact of various on-board storage options on fuel economy are evaluated. Experiments with an available engine at the Sandia Combustion Research Facility demonstrated NO(x) emissions of 10 to 20 ppm at an equivalence ratio of 0.4, rising to about 500 ppm at 0.5 equivalence ratio using neat hydrogen. Hybrid vehicle simulation studies indicate that exhaust NO(x) concentrations must be less than 180 ppm to meet the 0.2 g/mile California Air Resources Board ULEV or Federal Tier-2 emissions regulations. We have designed and fabricated a first generation optimized hydrogen engine head for use on an existing single cylinder Onan engine. This head currently features 14.8:1 compression ratio, dual ignition, water cooling, two valves and open quiescent combustion chamber to minimize heat transfer losses.

Power Requirements for Bi-Harmonic Amplitude and Bias Modulation Control of a Flapping Wing Micro Air Vehicle

DTIC Science & Technology

2013-03-01

acquisition DC Direct current DHPC Discrete harmonic plant compensation DLMs Dorsal longitudinal muscles DOE Design of experiments DOF Degrees of...nature, would have the inherent benefit of stealth through mimicry of insects. Such a MAV is referred to as a flapping wing micro air vehicle (FWMAV...and discrete harmonic plant compensation (DHPC) to manipulate the wings of the FWMAV. A clear understanding of what research has been done in all of

Robust flight design for an advanced launch system vehicle

NASA Astrophysics Data System (ADS)

Dhand, Sanjeev K.; Wong, Kelvin K.

Current launch vehicle trajectory design philosophies are generally based on maximizing payload capability. This approach results in an expensive trajectory design process for each mission. Two concepts of robust flight design have been developed to significantly reduce this cost: Standardized Trajectories and Command Multiplier Steering (CMS). These concepts were analyzed for an Advanced Launch System (ALS) vehicle, although their applicability is not restricted to any particular vehicle. Preliminary analysis has demonstrated the feasibility of these concepts at minimal loss in payload capability.

Optimization of entry-vehicle shapes during conceptual design

NASA Astrophysics Data System (ADS)

Dirkx, D.; Mooij, E.

2014-01-01

During the conceptual design of a re-entry vehicle, the vehicle shape and geometry can be varied and its impact on performance can be evaluated. In this study, the shape optimization of two classes of vehicles has been studied: a capsule and a winged vehicle. Their aerodynamic characteristics were analyzed using local-inclination methods, automatically selected per vehicle segment. Entry trajectories down to Mach 3 were calculated assuming trimmed conditions. For the winged vehicle, which has both a body flap and elevons, a guidance algorithm to track a reference heat-rate was used. Multi-objective particle swarm optimization was used to optimize the shape using objectives related to mass, volume and range. The optimizations show a large variation in vehicle performance over the explored parameter space. Areas of very strong non-linearity are observed in the direct neighborhood of the two-dimensional Pareto fronts. This indicates the need for robust exploration of the influence of vehicle shapes on system performance during engineering trade-offs, which are performed during conceptual design. A number of important aspects of the influence of vehicle behavior on the Pareto fronts are observed and discussed. There is a nearly complete convergence to narrow-wing solutions for the winged vehicle. Also, it is found that imposing pitch-stability for the winged vehicle at all angles of attack results in vehicle shapes which require upward control surface deflections during the majority of the entry.

Prediction of thermal behaviors of an air-cooled lithium-ion battery system for hybrid electric vehicles

NASA Astrophysics Data System (ADS)

Choi, Yong Seok; Kang, Dal Mo

2014-12-01

Thermal management has been one of the major issues in developing a lithium-ion (Li-ion) hybrid electric vehicle (HEV) battery system since the Li-ion battery is vulnerable to excessive heat load under abnormal or severe operational conditions. In this work, in order to design a suitable thermal management system, a simple modeling methodology describing thermal behavior of an air-cooled Li-ion battery system was proposed from vehicle components designer's point of view. A proposed mathematical model was constructed based on the battery's electrical and mechanical properties. Also, validation test results for the Li-ion battery system were presented. A pulse current duty and an adjusted US06 current cycle for a two-mode HEV system were used to validate the accuracy of the model prediction. Results showed that the present model can give good estimations for simulating convective heat transfer cooling during battery operation. The developed thermal model is useful in structuring the flow system and determining the appropriate cooling capacity for a specified design prerequisite of the battery system.

Maximizing Launch Vehicle and Payload Design Via Early Communications

NASA Technical Reports Server (NTRS)

Morris, Bruce

2010-01-01

The United States? current fleet of launch vehicles is largely derived from decades-old designs originally made for payloads that no longer exist. They were built primarily for national security or human exploration missions. Today that fleet can be divided roughly into small-, medium-, and large-payload classes based on mass and volume capability. But no vehicle in the U.S. fleet is designed to accommodate modern payloads. It is usually the payloads that must accommodate the capabilities of the launch vehicles. This is perhaps most true of science payloads. It was this paradigm that the organizers of two weekend workshops in 2008 at NASA's Ames Research Center sought to alter. The workshops brought together designers of NASA's Ares V cargo launch vehicle (CLV) with scientists and payload designers in the astronomy and planetary sciences communities. Ares V was still in a pre-concept development phase as part of NASA?s Constellation Program for exploration beyond low Earth orbit (LEO). The space science community was early in a Decadal Survey that would determine future priorities for research areas, observations, and notional missions to make those observations. The primary purpose of the meetings in April and August of 2008, including the novel format, was to bring vehicle designers together with space scientists to discuss the feasibility of using a heavy lift capability to launch large observatories and explore the Solar System. A key question put to the science community was whether this heavy lift capability enabled or enhanced breakthrough science. The meetings also raised the question of whether some trade-off between mass/volume and technical complexity existed that could reduce technical and programmatic risk. By engaging the scientific community early in the vehicle design process, vehicle engineers sought to better understand potential limitations and requirements that could be added to the Ares V from the mission planning community. From the vehicle

Resources and Fact Sheets on Servicing Motor Vehicle Air Conditioners (Summary Page)

EPA Pesticide Factsheets

Page provides links to resources that can assist motor vehicle air-conditioning system technicians in understanding system servicing requirements and best practices, and learn about alternative refrigerants.

Air Quality Impacts of Electrifying Vehicles and Equipment Across the United States.

PubMed

Nopmongcol, Uarporn; Grant, John; Knipping, Eladio; Alexander, Mark; Schurhoff, Rob; Young, David; Jung, Jaegun; Shah, Tejas; Yarwood, Greg

2017-03-07

U.S.-wide air quality impacts of electrifying vehicles and off-road equipment are estimated for 2030 using 3-D photochemical air quality model and detailed emissions inventories. Electrification reduces tailpipe emissions and emissions from petroleum refining, transport, and storage, but increases electricity demand. The Electrification Case assumes approximately 17% of light duty and 8% of heavy duty vehicle miles traveled and from 17% to 79% of various off-road equipment types considered good candidates for electrification is powered by electricity. The Electrification Case raises electricity demand by 5% over the 2030 Base Case but nitrogen oxide (NO x ) emissions decrease by 209 thousand tons (3%) overall. Emissions of other criteria pollutants also decrease. Air quality benefits of electrification are modest, mostly less than 1 ppb for ozone and 0.5 μg m -3 for fine particulate matter (PM 2.5 ), but widespread. The largest reductions for ozone and PM occur in urban areas due to lower mobile source emissions. Electrifying off-road equipment yields more benefits than electrifying on-road vehicles. Reduced crude oil imports and associated marine vessel emissions cause additional benefits in port cities. Changes in other gas and PM emissions, as well as impacts on acid and nutrient deposition, are discussed.

Multi-Reflex Propulsion Systems for Space and Air Vehicles and Energy Transfer for Long Distance

NASA Astrophysics Data System (ADS)

Bolonkin, A.

The purpose of this article is to call attention to the revolutionary idea of light multi-reflection. This idea allows the design of new engines, space and air propulsion systems, storage (of a beam and solar energy), transmitters of energy (to millions of kilometers), creation of new weapons, etc. This method and the main innovations were offered by the author in 1983 in the former USSR. Now the author shows in a series of articles the immense possibilities of this idea in many fields of engineering - astronautics, aviation, energy, optics, direct converter of light (laser beam) energy to mechanical energy (light engine), to name a few. This article considers the multi-reflex propulsion systems for space and air vehicles and energy transmitter for long distances in space.

Updraft Model for Development of Autonomous Soaring Uninhabited Air Vehicles

NASA Technical Reports Server (NTRS)

Allen, Michael J.

2006-01-01

Large birds and glider pilots commonly use updrafts caused by convection in the lower atmosphere to extend flight duration, increase cross-country speed, improve range, or simply to conserve energy. Uninhabited air vehicles may also have the ability to exploit updrafts to improve performance. An updraft model was developed at NASA Dryden Flight Research Center (Edwards, California) to investigate the use of convective lift for uninhabited air vehicles in desert regions. Balloon and surface measurements obtained at the National Oceanic and Atmospheric Administration Surface Radiation station (Desert Rock, Nevada) enabled the model development. The data were used to create a statistical representation of the convective velocity scale, w*, and the convective mixing-layer thickness, zi. These parameters were then used to determine updraft size, vertical velocity profile, spacing, and maximum height. This paper gives a complete description of the updraft model and its derivation. Computer code for running the model is also given in conjunction with a check case for model verification.

Control Relevant Modeling and Design of Scramjet-Powered Hypersonic Vehicles

NASA Astrophysics Data System (ADS)

Dickeson, Jeffrey James

This report provides an overview of scramjet-powered hypersonic vehicle modeling and control challenges. Such vehicles are characterized by unstable non-minimum phase dynamics with significant coupling and low thrust margins. Recent trends in hypersonic vehicle research are summarized. To illustrate control relevant design issues and tradeoffs, a generic nonlinear 3DOF longitudinal dynamics model capturing aero-elastic-propulsive interactions for wedge-shaped vehicle is used. Limitations of the model are discussed and numerous modifications have been made to address control relevant needs. Two different baseline configurations are examined over a two-stage to orbit ascent trajectory. The report highlights how vehicle level-flight static (trim) and dynamic properties change over the trajectory. Thermal choking constraints are imposed on control system design as a direct consequence of having a finite FER margin. The implication of this state-dependent nonlinear FER margin constraint, the right half plane (RHP) zero, and lightly damped flexible modes, on control system bandwidth (BW) and FPA tracking has been discussed. A control methodology has been proposed that addresses the above dynamics while providing some robustness to modeling uncertainty. Vehicle closure (the ability to fly a trajectory segment subject to constraints) is provided through a proposed vehicle design methodology. The design method attempts to use open loop metrics whenever possible to design the vehicle. The design method is applied to a vehicle/control law closed loop nonlinear simulation for validation. The 3DOF longitudinal modeling results are validated against a newly released NASA 6DOF code.

Design and analysis of multifunctional structures for embedded electronics in unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Kothari, Rushabh M.

Multifunctional structures are a new trend in the aerospace industry for the next generation structural design. Many future structures are expected to be something in addition to a load bearing structure. The design and analysis of multifunctional structures combining structural, electrical and thermal functionalities are presented here. The sandwich beam is considered as a starting point for the load bearing structure and then it is modified with a cavity to embed avionics and thermal controls. The embedded avionics inside the load bearing structure would allow weight reduction of the aerospace vehicle due to elimination of separate electronics housing, interconnects, cables etc. The cavity reduces strength of the structure so various reinforcements methods are evaluated. The result of various reinforcements and their effectiveness are presented. The current generation of electronics produce massive amount of heat. In the case of embedded electronics, the excessive heat presents a major challenge to the structural and heat transfer engineers. The embedded nature of electronics prevents the use of the classical heat dissipative methods such as fans and high velocity air flows, etc. The integrated thermal control of the electronics has been designed using passive heat transfer device and highly optimized particulate composite thermal interface material (TIM). The TIMs are used to fill the air gaps and reduce contact resistance between two surfaces, such as electronics and heat dissipators. The efficiency of TIM directly affects the overall heat transfer ability of the integrated thermal control system. The effect of the particles at micron and nano scales are studied for the particulate composite TIM. The thermal boundary resistance study for the particulate composite TIM with nano silica particles is presented in this thesis. The FEA analysis is used to model thermal boundary resistance and compared with the theoretical micromechanics model. The heat pipes are

Man-vehicle systems research facility: Design and operating characteristics

NASA Technical Reports Server (NTRS)

1983-01-01

The Man-Vehicle Systems Research Facility (MVSRF) provides the capability of simulating aircraft (two with full crews), en route and terminal air traffic control and aircrew interactions, and advanced cockpit (1995) display representative of future generations of aircraft, all within the full mission context. The characteristics of this facility derive from research, addressing critical human factors issues that pertain to: (1) information requirements for the utilization and integration of advanced electronic display systems, (2) the interaction and distribution of responsibilities between aircrews and ground controllers, and (3) the automation of aircrew functions. This research has emphasized the need for high fidelity in simulations and for the capability to conduct full mission simulations of relevant aircraft operations. This report briefly describes the MVSRF design and operating characteristics.

78 FR 20881 - Control of Air Pollution From Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-08

...The EPA is announcing two public hearings to be held for the proposed rule ``Control of Air Pollution from Motor Vehicles: Tier 3 Motor Vehicle Emission and Fuel Standards'' (the proposed rule is hereinafter referred to as ``Tier 3''), which will be published separately in the Federal Register. The hearings will be held in Philadelphia, PA on April 24, 2013 and in Chicago, IL on April 29, 2013. The comment period for the proposed rulemaking will end on June 13, 2013.

Application of optimization techniques to vehicle design: A review

NASA Technical Reports Server (NTRS)

Prasad, B.; Magee, C. L.

1984-01-01

The work that has been done in the last decade or so in the application of optimization techniques to vehicle design is discussed. Much of the work reviewed deals with the design of body or suspension (chassis) components for reduced weight. Also reviewed are studies dealing with system optimization problems for improved functional performance, such as ride or handling. In reviewing the work on the use of optimization techniques, one notes the transition from the rare mention of the methods in the 70's to an increased effort in the early 80's. Efficient and convenient optimization and analysis tools still need to be developed so that they can be regularly applied in the early design stage of the vehicle development cycle to be most effective. Based on the reported applications, an attempt is made to assess the potential for automotive application of optimization techniques. The major issue involved remains the creation of quantifiable means of analysis to be used in vehicle design. The conventional process of vehicle design still contains much experience-based input because it has not yet proven possible to quantify all important constraints. This restraint on the part of the analysis will continue to be a major limiting factor in application of optimization to vehicle design.

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In... group, will be equipped with an item (whether that item is standard equipment or an option), the full...

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In... group, will be equipped with an item (whether that item is standard equipment or an option), the full...

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In... group, will be equipped with an item (whether that item is standard equipment or an option), the full...

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In... group, will be equipped with an item (whether that item is standard equipment or an option), the full...

Preliminary subsystem designs for the Assured Crew Return Vehicle (ACRV)

NASA Technical Reports Server (NTRS)

1990-01-01

Described herein is a series of design studies concerning the Assured Crew Return Vehicle (ACRV). Study topics include a braking and landing system for the ACRV, ACRV growth options, and the design impacts of ACRV's role as a medical emergency vehicle. Four alternate designs are presented for the ACRV braking and landing system. Options presented include ballistic and lifting body reentries; the use of high-lift, high-payload aerodynamic decelerators, as well as conventional parachutes; landing systems designed for water landings, land landings or both; and an aerial recovery system. Uses of the ACRV or a similarly designed vehicle in several roles for possible future space missions are discussed, along with the required changes to the ACRV to allow it to perform these missions optimally. The impacts on the design of the ACRV due to its role as an emergency vehicle were studied and are presented here. This study included the design of a stretcher-like system to transport an ill or injured crewmember safely within the ACRV; a compilation of necessary medical equipment and decisions on how or where to store it; and recommendations about internal and external vehicle characteristics that will ease the transport of the ill or injured crewmember and allow for swift and easy ingress/egress of the vehicle.

Assessing the Link between Environmental Concerns and Consumers' Decisions to Use Clean-Air Vehicles

ERIC Educational Resources Information Center

Plax, Timothy G.; Kearney, Patricia; Ross, Ted J.; Jolly, J. Christopher

2008-01-01

A consulting contract with the California Air Resources Board led to a project examining how California drivers' and fleet managers' perceptions, attitudes, and consumer behavior regarding Clean Vehicle Technologies influenced their own energy choices when it came to purchasing vehicles. The consultants examined archival research, conducted focus…

78 FR 19991 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Motor Vehicle...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-03

... Environmental protection, Air pollution control, Incorporation by reference, Nitrogen dioxide, Particulate... Promulgation of Air Quality Implementation Plans; Pennsylvania; Motor Vehicle Emissions Budgets for the Pennsylvania Counties in the Philadelphia-Wilmington, PA-NJ-DE 1997 Fine Particulate Matter Nonattainment Area...

Design study of flat belt CVT for electric vehicles

NASA Technical Reports Server (NTRS)

Kumm, E. L.

1980-01-01

A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.

Measuring concentrations of selected air pollutants inside California vehicles : final report

DOT National Transportation Integrated Search

1998-12-01

This study provided the data needed to characterize in-transit exposures to air pollutants for California drivers. It also demonstrated a number of in-situ monitoring techniques in moving vehicles and provided findings that shed new light on particle...

Cleaning the air and improving health with hydrogen fuel-cell vehicles.

PubMed

Jacobson, M Z; Colella, W G; Golden, D M

2005-06-24

Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline.

Cleaning the Air and Improving Health with Hydrogen Fuel-Cell Vehicles

NASA Astrophysics Data System (ADS)

Jacobson, M. Z.; Colella, W. G.; Golden, D. M.

2005-06-01

Converting all U.S. onroad vehicles to hydrogen fuel-cell vehicles (HFCVs) may improve air quality, health, and climate significantly, whether the hydrogen is produced by steam reforming of natural gas, wind electrolysis, or coal gasification. Most benefits would result from eliminating current vehicle exhaust. Wind and natural gas HFCVs offer the greatest potential health benefits and could save 3700 to 6400 U.S. lives annually. Wind HFCVs should benefit climate most. An all-HFCV fleet would hardly affect tropospheric water vapor concentrations. Conversion to coal HFCVs may improve health but would damage climate more than fossil/electric hybrids. The real cost of hydrogen from wind electrolysis may be below that of U.S. gasoline.

Conceptual Launch Vehicle and Spacecraft Design for Risk Assessment

NASA Technical Reports Server (NTRS)

Motiwala, Samira A.; Mathias, Donovan L.; Mattenberger, Christopher J.

2014-01-01

One of the most challenging aspects of developing human space launch and exploration systems is minimizing and mitigating the many potential risk factors to ensure the safest possible design while also meeting the required cost, weight, and performance criteria. In order to accomplish this, effective risk analyses and trade studies are needed to identify key risk drivers, dependencies, and sensitivities as the design evolves. The Engineering Risk Assessment (ERA) team at NASA Ames Research Center (ARC) develops advanced risk analysis approaches, models, and tools to provide such meaningful risk and reliability data throughout vehicle development. The goal of the project presented in this memorandum is to design a generic launch 7 vehicle and spacecraft architecture that can be used to develop and demonstrate these new risk analysis techniques without relying on other proprietary or sensitive vehicle designs. To accomplish this, initial spacecraft and launch vehicle (LV) designs were established using historical sizing relationships for a mission delivering four crewmembers and equipment to the International Space Station (ISS). Mass-estimating relationships (MERs) were used to size the crew capsule and launch vehicle, and a combination of optimization techniques and iterative design processes were employed to determine a possible two-stage-to-orbit (TSTO) launch trajectory into a 350-kilometer orbit. Primary subsystems were also designed for the crewed capsule architecture, based on a 24-hour on-orbit mission with a 7-day contingency. Safety analysis was also performed to identify major risks to crew survivability and assess the system's overall reliability. These procedures and analyses validate that the architecture's basic design and performance are reasonable to be used for risk trade studies. While the vehicle designs presented are not intended to represent a viable architecture, they will provide a valuable initial platform for developing and demonstrating

Study on high reliability safety valve for railway vehicle

NASA Astrophysics Data System (ADS)

Zhang, Xuan; Chen, Ruikun; Zhang, Shixi; Xu, BuDu

2017-09-01

Now, the realization of most of the functions of the railway vehicles rely on compressed air, so the demand for compressed air is growing higher and higher. This safety valve is a protection device for pressure limitation and pressure relief in an air supply system of railway vehicles. I am going to introduce the structure, operating principle, research and development process of the safety valve designed by our company in this document.

Design Criteria for Low Risk Re-Entry Vehicles

NASA Astrophysics Data System (ADS)

Monti, R.; Pezzella, G.

2005-02-01

The paper shows how a sharp vehicle with low wing loading, is able to follow re-entry trajectories with low thermal risks by using Ultra High Temperature Ceramics (UHTC) to thermally protect the vehicle front edges. These reusable materials can withstand the global radiative equilibrium temperatures that are experienced during reentry characterized by a longer and a more gradual conversion of the kinetic and potential energy of the vehicle into thermal energy. A number of aerothermodynamic problems are addressed to assess the feasibility of the vehicle design and of the thermal protection of the payload. In particular, the boundary layer thermal protection concept is illustrated to show how a UHTC massive tip edges (fuselage and wings) are able to protect also the remaining vehicle structure made of conventional material, promoting a revolutionary approach to the Thermal Protection System (TPS) configuration for hypersonic vehicle flying at small angle of attack. CFD results and engineering formulations are adopted for the computation of the aerodynamic coefficients and heat fluxes. The analysis identifies the design criteria for a conventional looking vehicle for a crew return from LEO (e.g. from the International Space Station).

Designing Effective In-vehicle Icons

DOT National Transportation Integrated Search

1975-04-01

The design of a system for scanning sequences of aerial photographs with a computer-controlled flying-spot scanner and automatically measuring vehicle locations is described. Hardware and software requirements for an operational system of this type a...

Launch vehicle systems design analysis

NASA Technical Reports Server (NTRS)

Ryan, Robert; Verderaime, V.

1993-01-01

Current launch vehicle design emphasis is on low life-cycle cost. This paper applies total quality management (TQM) principles to a conventional systems design analysis process to provide low-cost, high-reliability designs. Suggested TQM techniques include Steward's systems information flow matrix method, quality leverage principle, quality through robustness and function deployment, Pareto's principle, Pugh's selection and enhancement criteria, and other design process procedures. TQM quality performance at least-cost can be realized through competent concurrent engineering teams and brilliance of their technical leadership.

Effect of air bags and restraining devices on the pattern of facial fractures in motor vehicle crashes.

PubMed

Simoni, Payman; Ostendorf, Robert; Cox, Artemus J

2003-01-01

To examine the relationship between the use of restraining devices and the incidence of specific facial fractures in motor vehicle crashes. Retrospective analysis of patients with facial fractures following a motor vehicle crash. University of Alabama at Birmingham Hospital level I trauma center from 1996 to 2000. Of 3731 patients involved in motor vehicle crashes, a total of 497 patients were found to have facial fractures as determined by International Classification of Diseases, Ninth Revision (ICD-9) codes. Facial fractures were categorized as mandibular, orbital, zygomaticomaxillary complex (ZMC), and nasal. Use of seat belts alone was more effective in decreasing the chance of facial fractures in this population (from 17% to 8%) compared with the use of air bags alone (17% to 11%). The use of seat belts and air bags together decreased the incidence of facial fractures from 17% to 5%. Use of restraining devices in vehicles significantly reduces the chance of incurring facial fractures in a severe motor vehicle crash. However, use of air bags and seat belts does not change the pattern of facial fractures greatly except for ZMC fractures. Air bags are least effective in preventing ZMC fractures. Improving the mechanics of restraining devices might be needed to minimize facial fractures.

Engineering Cost Analysis of the Urban-Tracked Air Cushion Vehicle System

DOT National Transportation Integrated Search

1972-01-01

The Urban Tracked Air Cushion Vehicle (UTACV) is presently being developed as a means of improving urban transportation. This report covers the development of a cost analysis conducted for the UTACV. The report covers the development of a computer pr...

System controls challenges of hypersonic combined-cycle engine powered vehicles

NASA Technical Reports Server (NTRS)

Morrison, Russell H.; Ianculescu, George D.

1992-01-01

Hypersonic aircraft with air-breathing engines have been described as the most complex and challenging air/space vehicle designs ever attempted. This is particularly true for aircraft designed to accelerate to orbital velocities. The propulsion system for the National Aerospace Plane will be an active factor in maintaining the aircraft on course. Typically addressed are the difficulties with the aerodynamic vehicle design and development, materials limitations and propulsion performance. The propulsion control system requires equal materials limitations and propulsion performance. The propulsion control system requires equal concern. Far more important than merely a subset of propulsion performance, the propulsion control system resides at the crossroads of trajectory optimization, engine static performance, and vehicle-engine configuration optimization. To date, solutions at these crossroads are multidisciplinary and generally lag behind the broader performance issues. Just how daunting these demands will be is suggested. A somewhat simplified treatment of the behavioral characteristics of hypersonic aircraft and the issues associated with their air-breathing propulsion control system design are presented.

The vehicle design evaluation program - A computer-aided design procedure for transport aircraft

NASA Technical Reports Server (NTRS)

Oman, B. H.; Kruse, G. S.; Schrader, O. E.

1977-01-01

The vehicle design evaluation program is described. This program is a computer-aided design procedure that provides a vehicle synthesis capability for vehicle sizing, external load analysis, structural analysis, and cost evaluation. The vehicle sizing subprogram provides geometry, weight, and balance data for aircraft using JP, hydrogen, or methane fuels. The structural synthesis subprogram uses a multistation analysis for aerodynamic surfaces and fuselages to develop theoretical weights and geometric dimensions. The parts definition subprogram uses the geometric data from the structural analysis and develops the predicted fabrication dimensions, parts material raw stock buy requirements, and predicted actual weights. The cost analysis subprogram uses detail part data in conjunction with standard hours, realization factors, labor rates, and material data to develop the manufacturing costs. The program is used to evaluate overall design effects on subsonic commercial type aircraft due to parameter variations.

Emissions of halocarbons from mobile vehicle air conditioning system in Hong Kong.

PubMed

Yan, H H; Guo, H; Ou, J M

2014-08-15

During the implementation of Montreal Protocol, emission inventories of halocarbons in different sectors at regional scale are fundamental to the formulation of relevant management strategy and inspection of the implementation efficiency. This study investigated the emission profile of halocarbons used in the mobile vehicle air conditioning system, the leading sector of refrigeration industry in terms of the refrigerant bank, market and emission, in the Hong Kong Special Administrative Region, using a bottom-up approach developed by 2006 IPCC Good Practice Guidance. The results showed that emissions of CFC-12 peaked at 53 tons ODP (Ozone Depletion Potential) in 1992 and then gradually diminished, whereas HFC-134a presented an increasing emission trend since 1990s and the emissions of HFC-134a reached 65,000 tons CO2-equivelant (CO2-eq) by the end of 2011. Uncertainty analysis revealed relatively high levels of uncertainties for special-purpose vehicles and government vehicles. Moreover, greenhouse gas (GHG) abatements under different scenarios indicated that potential emission reduction of HFC-134a ranged from 4.1 to 8.4 × 10(5)tons CO2-eq. The findings in this study advance our knowledge of halocarbon emissions from mobile vehicle air conditioning system in Hong Kong. Copyright © 2014 Elsevier B.V. All rights reserved.

Design of a vehicle based system to prevent ozone loss

NASA Technical Reports Server (NTRS)

Talbot, Matthew D.; Eby, Steven C.; Ireland, Glen J.; Mcwithey, Michael C.; Schneider, Mark S.; Youngblood, Daniel L.; Johnson, Matt; Taylor, Chris

1994-01-01

This project is designed to be completed over a three year period. Overall project goals are: (1) to understand the processes that contribute to stratospheric ozone loss; (2) to determine the best scheme to prevent ozone loss; and (3) to design a vehicle based system to carry out the prevention scheme. The 1993/1994 design objectives included: (1) to review the results of the 1992/1993 design team, including a reevaluation of the key assumptions used; (2) to develop a matrix of baseline vehicle concepts as candidates for the delivery vehicle; and (3) to develop a selection criteria and perform quantitative trade studies to use in the selection of the specific vehicle concept.

Launch vehicle design and GNC sizing with ASTOS

NASA Astrophysics Data System (ADS)

Cremaschi, Francesco; Winter, Sebastian; Rossi, Valerio; Wiegand, Andreas

2018-03-01

The European Space Agency (ESA) is currently involved in several activities related to launch vehicle designs (Future Launcher Preparatory Program, Ariane 6, VEGA evolutions, etc.). Within these activities, ESA has identified the importance of developing a simulation infrastructure capable of supporting the multi-disciplinary design and preliminary guidance navigation and control (GNC) design of different launch vehicle configurations. Astos Solutions has developed the multi-disciplinary optimization and launcher GNC simulation and sizing tool (LGSST) under ESA contract. The functionality is integrated in the Analysis, Simulation and Trajectory Optimization Software for space applications (ASTOS) and is intended to be used from the early design phases up to phase B1 activities. ASTOS shall enable the user to perform detailed vehicle design tasks and assessment of GNC systems, covering all aspects of rapid configuration and scenario management, sizing of stages, trajectory-dependent estimation of structural masses, rigid and flexible body dynamics, navigation, guidance and control, worst case analysis, launch safety analysis, performance analysis, and reporting.

A survey of aerobraking orbital transfer vehicle design concepts

NASA Technical Reports Server (NTRS)

Park, Chul

1987-01-01

The five existing design concepts of the aerobraking orbital transfer vehicle (namely, the raked sphere-cone designs, conical lifting-brake, raked elliptic-cone, lifting-body, and ballute) are reviewed and critiqued. Historical backgrounds, and the geometrical, aerothermal, and operational features of these designs are reviewed first. Then, the technological requirements for the vehicle (namely, navigation, aerodynamic stability and control, afterbody flow impingement, nonequilibrium radiation, convective heat-transfer rates, mission abort and multiple atmospheric passes, transportation and construction, and the payload-to-vehicle weight requirements) are delineated by summarizing the recent advancements made on these issues. Each of the five designs are critiqued and rated on these issues. The highest and the lowest ratings are given to the raked sphere-cone and the ballute design, respectively.

Aerodynamics of Tracked Ram Air Cushion Vehicles - Effects of Pitch Attitude and Upper Surface Flow

DOT National Transportation Integrated Search

1979-12-01

Three types of experiments were conducted on geometrically similar model of a Tracked Ram Air Cushion Vehicle (TRACV). The first consisted of wind tunnel tests with the vehicle model positioned within a short segment of stationary guideway. In the se...

Integration of an Autopilot for a Micro Air Vehicle

NASA Technical Reports Server (NTRS)

Platanitis, George; Shkarayev, Sergey

2005-01-01

Two autopilots providing autonomous flight capabilities are presented herein. The first is the Pico-Pilot, demonstrated for the 12-inch size class of micro air vehicles. The second is the MicroPilot MP2028(sup g), where its integration into a 36-inch Zagi airframe (tailless, elevons only configuration) is investigated and is the main focus of the report. Analytical methods, which include the use of the Advanced Aircraft Analysis software from DARCorp, were used to determine the stability and control derivatives, which were then validated through wind tunnel experiments. From the aerodynamic data, the linear, perturbed equations of motion from steady-state flight conditions may be cast in terms of these derivatives. Using these linear equations, transfer functions for the control and navigation systems were developed and feedback control laws based on Proportional, Integral, and Derivative (PID) control design were developed to control the aircraft. The PID gains may then be programmed into the autopilot software and uploaded to the microprocessor of the autopilot. The Pico-Pilot system was flight tested and shown to be successful in navigating a 12-inch MAV through a course defined by a number of waypoints with a high degree of accuracy, and in 20 mph winds. The system, though, showed problems with control authority in the roll and pitch motion of the aircraft: causing oscillations in these directions, but the aircraft maintained its heading while following the prescribed course. Flight tests were performed in remote control mode to evaluate handling, adjust trim, and test data logging for the Zagi with integrated MP2028(sup g). Ground testing was performed to test GPS acquisition, data logging, and control response in autonomous mode. Technical difficulties and integration limitations with the autopilot prevented fully autonomous flight from taking place, but the integration methodologies developed for this autopilot are, in general, applicable for unmanned air

Design of Omni Directional Remotely Operated Vehicle (ROV)

NASA Astrophysics Data System (ADS)

Rahimuddin; Hasan, Hasnawiya; Rivai, Haryanti A.; Iskandar, Yanu; Claudio, P.

2018-02-01

Nowadays, underwater activities are increased with the increase of oil resources finding. The gap between demand and supply of oil and gas cause engineers to find oil and gas resources in deep water. In other side, high risk of working in deep underwater environment can cause a dangerous situation for human. Therefore, many research activities are developing an underwater vehicle to replace the human’s work such as ROV or Remotely Operated Vehicles. The vehicle operated using tether to transport the signals and electric power from the surface vehicle. Arrangements of weight, buoyancy, and the propeller placements are significant aspect in designing the vehicle’s performance. This paper presents design concept of ROV for survey and observation the underwater objects with interaction vectored propellers used for vehicle’s motions.

Structural Design and Analysis of Un-pressurized Cargo Delivery Vehicle

NASA Technical Reports Server (NTRS)

Martinovic, Zoran N.

2007-01-01

As part of the Exploration Systems Architecture Study, NASA has defined a family of vehicles to support lunar exploration and International Space Station (ISS) re-supply missions after the Shuttle s retirement. The Un-pressurized Cargo Delivery Vehicle (UCDV) has been envisioned to be an expendable logistics delivery vehicle that would be used to deliver external cargo to the ISS. It would be launched on the Crew Launch Vehicle and would replace the Crew Exploration Vehicle. The estimated cargo would be the weight of external logistics to the ISS. Determining the minimum weight design of the UCDV during conceptual design is the major issue addressed in this paper. This task was accomplished using a procedure for rapid weight estimation that was based on Finite Element Analysis and sizing of the vehicle by the use of commercially available codes. Three design concepts were analyzed and their respective weights were compared. The analytical structural weight was increased by a factor to account for structural elements that were not modeled. Significant reduction in weight of a composite design over metallic was achieved for similar panel concepts.

Spacecraft rendezvous operational considerations affecting vehicle systems design and configuration

NASA Astrophysics Data System (ADS)

Prust, Ellen E.

One lesson learned from Orbiting Maneuvering Vehicle (OMV) program experience is that Design Reference Missions must include an appropriate balance of operations and performance inputs to effectively drive vehicle systems design and configuration. Rendezvous trajectory design is based on vehicle characteristics (e.g., mass, propellant tank size, and mission duration capability) and operational requirements, which have evolved through the Gemini, Apollo, and STS programs. Operational constraints affecting the rendezvous final approach are summarized. The two major objectives of operational rendezvous design are vehicle/crew safety and mission success. Operational requirements on the final approach which support these objectives include: tracking/targeting/communications; trajectory dispersion and navigation uncertainty handling; contingency protection; favorable sunlight conditions; acceptable relative state for proximity operations handover; and compliance with target vehicle constraints. A discussion of the ways each of these requirements may constrain the rendezvous trajectory follows. Although the constraints discussed apply to all rendezvous, the trajectory presented in 'Cargo Transfer Vehicle Preliminary Reference Definition' (MSFC, May 1991) was used as the basis for the comments below.

Determining air quality and greenhouse gas impacts of hydrogen infrastructure and fuel cell vehicles.

PubMed

Stephens-Romero, Shane; Carreras-Sospedra, Marc; Brouwer, Jacob; Dabdub, Donald; Samuelsen, Scott

2009-12-01

Adoption of hydrogen infrastructure and hydrogen fuel cell vehicles (HFCVs) to replace gasoline internal combustion engine (ICE) vehicles has been proposed as a strategy to reduce criteria pollutant and greenhouse gas (GHG) emissions from the transportation sector and transition to fuel independence. However, it is uncertain (1) to what degree the reduction in criteria pollutants will impact urban air quality, and (2) how the reductions in pollutant emissions and concomitant urban air quality impacts compare to ultralow emission gasoline-powered vehicles projected for a future year (e.g., 2060). To address these questions, the present study introduces a "spatially and temporally resolved energy and environment tool" (STREET) to characterize the pollutant and GHG emissions associated with a comprehensive hydrogen supply infrastructure and HFCVs at a high level of geographic and temporal resolution. To demonstrate the utility of STREET, two spatially and temporally resolved scenarios for hydrogen infrastructure are evaluated in a prototypical urban airshed (the South Coast Air Basin of California) using geographic information systems (GIS) data. The well-to-wheels (WTW) GHG emissions are quantified and the air quality is established using a detailed atmospheric chemistry and transport model followed by a comparison to a future gasoline scenario comprised of advanced ICE vehicles. One hydrogen scenario includes more renewable primary energy sources for hydrogen generation and the other includes more fossil fuel sources. The two scenarios encompass a variety of hydrogen generation, distribution, and fueling strategies. GHG emissions reductions range from 61 to 68% for both hydrogen scenarios in parallel with substantial improvements in urban air quality (e.g., reductions of 10 ppb in peak 8-h-averaged ozone and 6 mug/m(3) in 24-h-averaged particulate matter concentrations, particularly in regions of the airshed where concentrations are highest for the gasoline scenario).

A trajectory design method via target practice for air-breathing hypersonic vehicle

NASA Astrophysics Data System (ADS)

Kong, Xue; Yang, Ming; Ning, Guodong; Wang, Songyan; Chao, Tao

2017-11-01

There are strong coupling interactions between aerodynamics and scramjet, this kind of aircraft also has multiple restrictions, such as the range and difference of dynamic pressure, airflow, and fuel. On the one hand, we need balance the requirement between maneuverability of vehicle and stabilization of scramjet. On the other hand, we need harmonize the change of altitude and the velocity. By describing aircraft's index system of climbing capability, acceleration capability, the coupling degree in aerospace, this paper further propose a rapid design method which based on target practice. This method aimed for reducing the coupling degree, it depresses the coupling between aircraft and engine in navigation phase, satisfy multiple restriction conditions to leave some control buffer and create good condition for control implementation. According to the simulation, this method could be used for multiple typical fly commissions such as climbing, acceleration or both.

40 CFR 86.1832-01 - Optional equipment and air conditioning for test vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Compliance Provisions for Control of Air Pollution From New and In-Use Light...-01: (a)(1) Where it is expected that more than 33 percent of a car line, within a test group, will be...

An Ejector Air Intake Design Method for a Novel Rocket-Based Combined-Cycle Rocket Nozzle

NASA Astrophysics Data System (ADS)

Waung, Timothy S.

Rocket-based combined-cycle (RBCC) vehicles have the potential to reduce launch costs through the use of several different air breathing engine cycles, which reduce fuel consumption. The rocket-ejector cycle, in which air is entrained into an ejector section by the rocket exhaust, is used at flight speeds below Mach 2. This thesis develops a design method for an air intake geometry around a novel RBCC rocket nozzle design for the rocket-ejector engine cycle. This design method consists of a geometry creation step in which a three-dimensional intake geometry is generated, and a simple flow analysis step which predicts the air intake mass flow rate. The air intake geometry is created using the rocket nozzle geometry and eight primary input parameters. The input parameters are selected to give the user significant control over the air intake shape. The flow analysis step uses an inviscid panel method and an integral boundary layer method to estimate the air mass flow rate through the intake geometry. Intake mass flow rate is used as a performance metric since it directly affects the amount of thrust a rocket-ejector can produce. The design method results for the air intake operating at several different points along the subsonic portion of the Ariane 4 flight profile are found to under predict mass flow rate by up to 8.6% when compared to three-dimensional computational fluid dynamics simulations for the same air intake.

Design, Analysis and Qualification of Elevon for Reusable Launch Vehicle

NASA Astrophysics Data System (ADS)

Tiwari, S. B.; Suresh, R.; Krishnadasan, C. K.

2017-12-01

Reusable launch vehicle technology demonstrator is configured as a winged body vehicle, designed to fly in hypersonic, supersonic and subsonic regimes. The vehicle will be boosted to hypersonic speeds after which the winged body separates and descends using aerodynamic control. The aerodynamic control is achieved using the control surfaces mainly the rudder and the elevon. Elevons are deflected for pitch and roll control of the vehicle at various flight conditions. Elevons are subjected to aerodynamic, thermal and inertial loads during the flight. This paper gives details about the configuration, design, qualification and flight validation of elevon for Reusable Launch Vehicle.

Considerations on vehicle design criteria for space tourism

NASA Astrophysics Data System (ADS)

Isozaki, Kohki; Taniuchi, Akira; Yonemoto, Koichi; Kikukawa, Hiroshige; Maruyama, Tomoko

1995-10-01

The transportation research committee of JRS (Japanese Rocket Society) has begun conceptual design of vertical takeoff and landing fully reusable SSTO (Single Stage to Orbit) rocket type vehicle as a standard vehicle model for space tourism. The design criteria of the vehicle have paid most attention to the requirements of service to meet space tour amusement. The standard vehicle, which has 22m body length and weighs about 550 tons at takeoff, can provide attractive tours of 24 hours maximum for 50 passengers into the low earth orbit with a variety of space flight pleasures such as experience of weightlessness and earth sightseeing. Within the reach of our near future rocket technology, the design utilizes MMC, CF/Epy and Ti/Mw advanced materials. The twelve LOX/LH2 engines consist of two nozzle types, which can be throttled and gimbaled during the whole mission time, perform vertical launch and tail-first reentry to final landing associated with aerodynamic control of body flaps within tolerable acceleration acting on passengers.

Final Rule for Control of Air Pollution From New Motor Vehicles and New Motor Vehicle Engines; Non-Conformance Penalties for 2004 and later Model Year Emission Standards for Heavy-Duty Diesel Engines and Heavy-Duty Diesel Vehicles

EPA Pesticide Factsheets

Final Rule for Control of Air Pollution From New Motor Vehicles and New Motor Vehicle Engines; Non-Conformance Penalties for 2004 and later Model Year Emission Standards for Heavy-Duty Diesel Engines and Heavy-Duty Diesel Vehicles

Design of a Vehicle Based Intervention System to Prevent Ozone Loss

NASA Technical Reports Server (NTRS)

Cole, Robin; Fisher, Daniel; Meade, Matt; Neel, James; Olson, Kristin; Pittman, Andrew; Valdivia, Anne; Wibisono, Aria; Mason, William H.; Kirschbaum, Nathan

1995-01-01

This project was designed to be completed over a period of three years. Overall project goals were: (1) To understand the processes that contribute to stratospheric ozone loss; (2) To determine the best prevention scheme for loss; (3) To design a delivery vehicle to accomplish the prevention scheme. The 1994-1995 design objectives included: (1) To review the results of the 1993-1994 design team, including a reevaluation of the major assumptions and criteria selected to choose a vehicle; (2) To evaluate preliminary vehicle concepts and perform quantitative trade studies to select the optimal vehicle concept.

Fire hazard considerations for composites in vehicle design

NASA Technical Reports Server (NTRS)

Gordon, Rex B.

1994-01-01

Military ground vehicles fires are a significant cause of system loss, equipment damage, and crew injury in both combat and non-combat situations. During combat, the ability to successfully fight an internal fire, without losing fighting and mobility capabilities, is often the key to crew survival and mission success. In addition to enemy hits in combat, vehicle fires are initiated by electrical system failures, fuel line leaks, munitions mishaps and improper personnel actions. If not controlled, such fires can spread to other areas of the vehicle, causing extensive damage and the potential for personnel injury and death. The inherent fire safety characteristics (i.e. ignitability, compartments of these vehicles play a major roll in determining rather a newly started fire becomes a fizzle or a catastrophe. This paper addresses a systems approach to assuring optimum vehicle fire safety during the design phase of complex vehicle systems utilizing extensive uses of composites, plastic and related materials. It provides practical means for defining the potential fire hazard risks during a conceptual design phase, and criteria for the selection of composite materials based on its fire safety characteristics.

Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

2006-01-01

This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

Assessment of Urban Aerial Taxi with Cryogenic Components Under Design Environment for Novel Vertical Lift Vehicles (DELIVER)

NASA Technical Reports Server (NTRS)

Snyder, Christopher

2017-01-01

Assessing the potential to bring 100 years of aeronautics knowledge to the entrepreneurs desktop to enable a design environment for emerging vertical lift vehicles is one goal for the NASA's Design Environment for Novel Vertical Lift Vehicles (DELIVER). As part of this effort, a system study was performed using a notional, urban aerial taxi system to better understand vehicle requirements along with the tools and methods capability to assess these vehicles and their subsystems using cryogenic cooled components. The baseline was a vertical take-off and landing (VTOL) aircraft, with all-electric propulsion system assuming 15 year technology performance levels and its capability limited to a pilot with one or two people and cargo. Hydrocarbon-fueled hybrid concepts were developed to improve mission capabilities. The hybrid systems resulted in significant improvements in maximum range and number of on demand mobility (ODM) missions that could be completed before refuel or recharge. An important consideration was thermal management, including the choice for air-cooled or cryogenic cooling using liquid natural gas (LNG) fuel. Cryogenic cooling for critical components can have important implications on component performance and size. Thermal loads were also estimated, subsequent effort will be required to verify feasibility for cooling airflow and packaging. LNG cryogenic cooling of selected components further improved vehicle range and reduced thermal loads, but the same concerns for airflow and packaging still need to be addressed. The use of the NASA Design and Analysis of Rotorcraft (NDARC) tool for vehicle sizing and mission analysis appears to be capable of supporting analyses for present and future types of vehicles, missions, propulsion, and energy sources. Further efforts are required to develop verified models for these new types of propulsion and energy sources in the size and use envisioned for these emerging vehicle and mission classes.

Assessment of Urban Aerial Taxi with Cryogenic Components under Design Environment for Novel Vertical Lift Vehicles (DELIVER)

NASA Technical Reports Server (NTRS)

Snyder, Christopher A.

2017-01-01

Assessing the potential to bring 100 years of aeronautics knowledge to the entrepreneurs desktop to enable a design environment for emerging vertical lift vehicles is one goal for the NASAs Design Environment for Novel Vertical Lift Vehicles (DELIVER). As part of this effort, a system study was performed using a notional, urban aerial taxi system to better understand vehicle requirements along with the tools and methods capability to assess these vehicles and their subsystems using cryogenic cooled components. The baseline was a vertical take-off and landing (VTOL) aircraft, with all-electric propulsion system assuming 15 year technology performance levels and its capability limited to a pilot with one or two people and cargo. Hydrocarbon-fueled hybrid concepts were developed to improve mission capabilities. The hybrid systems resulted in significant improvements in maximum range and number of on demand mobility (ODM) missions that could be completed before refuel or recharge. An important consideration was thermal management, including the choice for air-cooled or cryogenic cooling using liquid natural gas (LNG) fuel. Cryogenic cooling for critical components can have important implications on component performance and size. Thermal loads were also estimated, subsequent effort will be required to verify feasibility for cooling airflow and packaging. LNG cryogenic cooling of selected components further improved vehicle range and reduced thermal loads, but the same concerns for airflow and packaging still need to be addressed. The use of the NASA Design and Analysis of Rotorcraft (NDARC) tool for vehicle sizing and mission analysis appears to be capable of supporting analyses for present and future types of vehicles, missions, propulsion, and energy sources. Further efforts are required to develop verified models for these new types of propulsion and energy sources in the size and use envisioned for these emerging vehicle and mission classes.

Deaths among drivers and right-front passengers in frontal collisions: redesigned air bags relative to first-generation air bags.

PubMed

Braver, Elisa R; Scerbo, Marge; Kufera, Joseph A; Alexander, Melvin T; Volpini, Karen; Lloyd, Joseph P

2008-03-01

After automakers were allowed the option of using sled tests for unbelted male dummies to certify the frontal crash performance of vehicles, most frontal air bags were depowered, starting in model year 1998, to reduce deaths and serious injuries arising from air bag deployments. Concern has been expressed that depowering air bags could compromise the protection of adult occupants. This study aimed to determine the effects of changes in air bag designs on risk of death among front-seat occupants. Deaths among drivers and right-front passengers per involvement in frontal police-reported crashes during calendar years 1998-2004 were compared among vehicles with sled-certified air bags (model years 1998-2004) and first-generation air bags (model years 1994-97). Frontal crash deaths were identified from the Fatality Analysis Reporting System. National estimates of police-reported crashes were derived from the National Automotive Sampling System/General Estimates System. Sled certification status for model years 1998-2004 was ascertained from published federal data and a survey of automobile manufacturers. Passenger cars, pickup trucks, sport utility vehicles, and minivans were studied. Stratified analyses were done to compute risk ratios (RR) and 95% confidence intervals (95% CI) for driver and right-front passenger deaths by air bag generation and crash, vehicle, and driver characteristics. In frontal crashes, overall RRs were 0.89 for driver deaths (95% CI = 0.74-1.08) and 0.89 for right-front passenger deaths (95% CI = 0.74-1.07) in sled-certified vehicles compared with first-generation air bag-equipped vehicles. Child right-front passengers (ages 0-4, 5-9) in vehicles with sled-certified air bags had statistically significant reductions in risk of dying in frontal collisions, including a 65% reduced risk among ages 0-4 (RR = 0.35; 95% CI = 0.21-0.60). No differences in effects of sled-certified air bags were observed between drivers ages 15-59 and 60-74 in sled

Space Vehicle Terrestrial Environment Design Requirements Guidelines

NASA Technical Reports Server (NTRS)

Johnson, Dale L.; Keller, Vernon W.; Vaughan, William W.

2006-01-01

The terrestrial environment is an important driver of space vehicle structural, control, and thermal system design. NASA is currently in the process of producing an update to an earlier Terrestrial Environment Guidelines for Aerospace Vehicle Design and Development Handbook. This paper addresses the contents of this updated handbook, with special emphasis on new material being included in the areas of atmospheric thermodynamic models, wind dynamics, atmospheric composition, atmospheric electricity, cloud phenomena, atmospheric extremes, and sea state. In addition, the respective engineering design elements are discussed relative to terrestrial environment inputs that require consideration. Specific lessons learned that have contributed to the advancements made in the application and awareness of terrestrial environment inputs for aerospace engineering applications are presented.

Vehicle cabin cooling system for capturing and exhausting heated boundary layer air from inner surfaces of solar heated windows

DOEpatents

Farrington, Robert B.; Anderson, Ren

2001-01-01

The cabin cooling system includes a cooling duct positioned proximate and above upper edges of one or more windows of a vehicle to exhaust hot air as the air is heated by inner surfaces of the windows and forms thin boundary layers of heated air adjacent the heated windows. The cabin cooling system includes at least one fan to draw the hot air into the cooling duct at a flow rate that captures the hot air in the boundary layer without capturing a significant portion of the cooler cabin interior air and to discharge the hot air at a point outside the vehicle cabin, such as the vehicle trunk. In a preferred embodiment, the cooling duct has a cross-sectional area that gradually increases from a distal point to a proximal point to the fan inlet to develop a substantially uniform pressure drop along the length of the cooling duct. Correspondingly, this cross-sectional configuration develops a uniform suction pressure and uniform flow rate at the upper edge of the window to capture the hot air in the boundary layer adjacent each window.

Modeling of the thermal comfort in vehicles using COMSOL multiphysics

NASA Astrophysics Data System (ADS)

Gavrila, Camelia; Vartires, Andreea

2016-12-01

The environmental quality in vehicles is a very important aspect of building design and evaluation of the influence of the thermal comfort inside the car for ensuring a safe trip. The aim of this paper is to modeling and simulating the thermal comfort inside the vehicles, using COMSOL Multiphysics program, for different ventilation grilles. The objective will be the implementing innovative air diffusion grilles in a prototype vehicle. The idea behind this goal is to introduce air diffusers with a special geometry allowing improving mixing between the hot or the cold conditioned air introduced in the cockpit and the ambient.

The potential impacts of electric vehicles on air quality in the urban areas of Barcelona and Madrid (Spain)

NASA Astrophysics Data System (ADS)

Soret, A.; Guevara, M.; Baldasano, J. M.

2014-12-01

This work analyses the potential air quality improvements resulting from three fleet electrification scenarios (∼13, 26 and 40%) by replacing conventional vehicles with Electric Battery Vehicles (EBVs), Plug-in Hybrid Electric Vehicles (PHEVs) and Hybrid Electric Vehicles (HEVs). This study has been performed for the cities of Barcelona and Madrid (Spain), where road transport is the primary emission source. In these urban areas, several air quality problems are present, mainly related to NO2 and particulate matter. The WRF-ARW/HERMESv2/CMAQ model system has been applied at high spatial (1 × 1 km2) and temporal (1 h) resolution. The results show that fleet electrification offers a potential for emission abatement, especially related to NOx and CO. Regarding the more ambitious scenario (∼40% fleet electrification), reductions of 11% and 17% of the total NOx emissions are observed in Barcelona and Madrid respectively. These emissions reductions involve air quality improvements in NO2 maximum hourly values up to 16%: reductions up to 30 and 35 μg m-3 in Barcelona and Madrid, respectively. Furthermore, an additional scenario has been defined considering electric generation emissions associated with EBVs and PHEVs charging from a combined-cycle power plant. These charging emissions would produce slight NO2 increases in the downwind areas of <3 μg m-3. Thus, fleet electrification would improve urban air quality even when considering emissions associated with charging electric vehicles. However, two further points should be considered. First, fleet electrification cannot be considered a unique solution, and other management strategies may be defined. This is especially important with respect to particulate matter emissions, which are not significantly reduced by fleet electrification (<5%) due to the high weight of non-exhaust emissions. Second, a significant introduction of electric vehicles (26-40%) involving all vehicle categories is required to improve urban

Guaranteed cost control with poles assignment for a flexible air-breathing hypersonic vehicle

NASA Astrophysics Data System (ADS)

Li, Hongyi; Si, Yulin; Wu, Ligang; Hu, Xiaoxiang; Gao, Huijun

2011-05-01

This article investigates the problem of guaranteed cost control for a flexible air-breathing hypersonic vehicle (FAHV). The FAHV includes intricate coupling between the engine and flight dynamics as well as complex interplay between flexible and rigid modes, which results in an intractable system for the control design. A longitudinal model is adopted for control design due to the complexity of the vehicle. First, for a highly nonlinear and coupled FAHV, a linearised model is established around the trim condition, which includes the state of altitude, velocity, angle of attack, pitch angle and pitch rate, etc. Secondly, by using the Lyapunov approach, performance analysis is carried out for the resulting closed-loop FAHV system, whose criterion with respect to guaranteed performance cost and poles assignment is expressed in the framework of linear matrix inequalities (LMIs). The established criterion exhibits a kind of decoupling between the Lyapunov positive-definite matrices to be determined and the FAHV system matrices, which is enabled by the introduction of additional slack matrix variables. Thirdly, a convex optimisation problem with LMI constraints is formulated for designing an admissible controller, which guarantees a prescribed performance cost with the simultaneous consideration of poles assignment for the resulting closed-loop system. Finally, some simulation results are provided to show that the guaranteed cost controller could assign the poles into the desired regional and achieve excellent reference altitude and velocity tracking performance.

Low Life Cycle Cost Paratransit Vehicle Design Study

DOT National Transportation Integrated Search

1978-08-01

A preliminary design and cost study was performed for a low life cycle cost paratransit vehicle. The manufacturing technique and cost analysis were based on limited production of 5000 units per year for a ten year period. The vehicle configuration re...

A lunar construction shack vehicle: Final design

NASA Technical Reports Server (NTRS)

1988-01-01

A lunar construction shack vehicle is a critical component in most of the plans proposed for the construction of a permanent base on the moon. The Selene Engineering Company (SEC) has developed a concept for this vehicle which is both innovative and practical. The design makes use of the most advanced technology available to meet the goals for a safe, versatile and durable habitat that will serve as a starting point for the initial phase of the construction of a permanent lunar base. This document outlines SEC's proposed design for a lander vehicle which will be fully self-sufficient and will provide for all necessary life support, including consumables and radiation protection, needed by the construction crew until they can complete the assembly of a more permanent habitat. Since it is highly likely that it will take more than one crew to complete the construction of a permanent lunar base, the design emphasis is on systems which can be easily maintained and resupplied and which will take a minimum of start up preparation by succeeding crews.

[Design and application of portable rescue vehicle].

PubMed

Guo, Ying; Qi, Huaying; Wang, Shen

2017-12-01

The disease of critically ill patients was with rapid changes, and at any time faced the risk of emergency. The current commonly used rescue vehicles were larger and bulky implementation, which were not conducive to the operation, therefore the design of a portable rescue vehicle was needed. This new type of rescue vehicle is multi-layer folding structure, with small footprint, large storage space, so a variety of first aid things can be classified and put, easy to be cleaned and disinfected. In the rescue process, the portable rescue vehicles can be placed in the required position; box of various emergency items can be found at a glance with easy access; the height of the infusion stand can adjust freely according to the user height; the rescue vehicle handle can be easy to pull and adjust accord with human body mechanics principle. The portable rescue vehicle facilitates the operation of medical staff, and is worthy of clinical application.

Dynamic issues in launch vehicle design

NASA Technical Reports Server (NTRS)

Ryan, Robert S.; Jewell, Ronald E.

1993-01-01

Launch vehicles, in general, have been defined using performance requirements and generic payload characteristics which dictated the propulsion system and the payload carrier. The vehicle concept is then selected using these requirements in conjunction with basic criteria and standards. During the design phase, the selected concept must be modified in order to cope with the numerous dynamic and other problems that occur during design and development. This is costly and is, to some extent, unnecessary. The purpose of this paper is to propose an approach for bringing the dynamic issues into focus during concept selection, where the greatest payoff exists. Delaying consideration of the issues to the design phases creates many problems, not the least of which are the impacts levied against the payload community. Volumes of information exist from prior programs on these dynamic issues and serve as the guidelines for this paper.

77 FR 3386 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Clean Vehicles Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-24

... Vehicle Program, which adopts California's second generation low emission vehicle program for light- duty... listed in the electronic docket, some information is not publicly available, i.e., confidential business....regulations.gov or in hard copy for public inspection during normal business hours at the Air Protection...

Design of a fast crew transfer vehicle to Mars

NASA Technical Reports Server (NTRS)

1988-01-01

A final report is made on the trajectory and vehicle requirements for a fast crew transfer vehicle to Mars which will complete an Earth to Mars (and Mars to Earth) transfer in 150 days and will have a stay time at Mars of 40 days. This vehicle will maximize the crew's effectiveness on Mars by minimizing detrimental physiological effects such as bone demineralization and loss of muscle tone caused by long period exposure to zero gravity and radiation from cosmic rays and solar flares. The crew transfer vehicle discussed will complete the second half of a Split Mission to Mars. In the Split Mission, a slow, unmanned cargo vehicle, nicknamed the Barge, is sent to Mars ahead of the crew vehicle. Once the Barge is in orbit around Mars, the fast crew vehicle will be launched to rendezvous with the Barge in Mars orbit. The vehicle presented is designed to carry six astronauts for a mission duration of one year. The vehicle uses a chemical propulsion system and a nuclear power system. Four crew modules, similar to the proposed Space Station Common Modules, are used to house the crew and support equipment during the mission. The final design also includes a command module that is shielded to protect the crew during radiation events.

Spatially- and Temporally-Resolved Measurements of Roadway Air Pollution Using a Zero-Emission Electric Vehicle

EPA Science Inventory

Vehicle-related air pollution has an intrinsically dynamic nature. Recent field measurements and modeling work have demonstrated that near-road topography may modify levels of air pollutants reaching populations residing and working in close proximity to roadways. However, the ma...

Investigation of the Landing Characteristics of a Re-entry Vehicle Having a Canted Multiple Air Bag Load Alleviation System

NASA Technical Reports Server (NTRS)

McGehee, John R.; Stubbs, Sandy M.

1963-01-01

An investigation was made to determine the landing-impact characteristics of a reentry vehicle having a multiple-air-bag load-alleviation system. A 1/16-scale dynamic model having four canted air bags was tested at flight-path angles of 90 degrees (vertical), 45 degrees, and 27 degrees for a parachute or paraglider vertical letdown velocity of 30 feet per second (full scale). Landings were made on concrete at attitudes ranging from -l5 degrees to 20 degrees. The friction coefficient between the model heat shield and the concrete was approximately 0.4. An aluminum diaphragm, designed to rupture at 10.8 pounds per square inch gage, was used to maintain initial pressure in the air bags for a short time period.

Experimental Investigation of Aerodynamic Characteristics of a Tracked Ram Air Cushion Vehicle

DOT National Transportation Integrated Search

1978-01-01

The results of an experimental and theoretical investigation of the longitudinal aerodynamic characteristics of a tracked ram air cushion vehicle are presented. Experiments have been conducted both in a wind tunnel with a model and section of guidewa...

77 FR 73459 - California State Motor Vehicle Pollution Control Standards; Notice of Waiver of Clean Air Act...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... Standards; Notice of Waiver of Clean Air Act Preemption; California's 2010 Model Year Heavy-Duty Vehicle and... its amendments to California's heavy-duty vehicle and engine on-board diagnostic (HD OBD) requirements... California's requirements in order to produce heavy-duty vehicles and engines for sale in California. For...

77 FR 17344 - Protection of Stratospheric Ozone: Amendment to HFO-1234yf SNAP Rule for Motor Vehicle Air...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-26

...-depleting substances (ODSs) in the motor vehicle air conditioning end-use within the refrigeration and air... part 82). These sectors--refrigeration and air conditioning; foam blowing; cleaning solvents; fire...

Hypersonic airbreathing vehicle conceptual design (focus on aero-space plane)

NASA Technical Reports Server (NTRS)

Hunt, James L.; Martin, John G.

1989-01-01

The airbreathing single stage to orbit (SSTO) vehicle design environment is variable-rich, intricately networked and sensitivity intensive. As such, it represents a tremondous technology challenge. Creating a viable design will require sophisticated configuration/synthesis and the synergistic integration of advanced technologies across the discipline spectrum. In design exercises, reductions in the fuel weight-fraction requirements projected for an orbital vehicle concept can result from improvements in aerodynamics/controls, propulsion efficiencies and trajectory optimization; also, gains in the fuel weight-fraction achievable for such a concept can result from improvements in structural design, heat management techniques, and material properties. As these technology advances take place, closure on a viable vehicle design will be realizable.

Terminal Sliding Mode Tracking Controller Design for Automatic Guided Vehicle

NASA Astrophysics Data System (ADS)

Chen, Hongbin

2018-03-01

Based on sliding mode variable structure control theory, the path tracking problem of automatic guided vehicle is studied, proposed a controller design method based on the terminal sliding mode. First of all, through analyzing the characteristics of the automatic guided vehicle movement, the kinematics model is presented. Then to improve the traditional expression of terminal sliding mode, design a nonlinear sliding mode which the convergence speed is faster than the former, verified by theoretical analysis, the design of sliding mode is steady and fast convergence in the limited time. Finally combining Lyapunov method to design the tracking control law of automatic guided vehicle, the controller can make the automatic guided vehicle track the desired trajectory in the global sense as well as in finite time. The simulation results verify the correctness and effectiveness of the control law.

Health effects associated with passenger vehicles: monetary values of air pollution.

PubMed

Marzouk, Mohamed; Madany, Magdy

2012-01-01

Air pollution is regarded as one of the highest priorities in environmental protection in both developed and developing countries. High levels of air pollution have adverse effects on human health that might cause premature death. This study presents the monetary value estimates for the adverse human health effects resulted from ambient air pollution. It aids decision makers to set priorities in the public health relevance of pollution abatement. The main driver of policymaker is the need to reduce the avoidable cardiopulmonary morbidity and mortality from pollutant exposures. The monetary valuation involves 2 steps: (i) relate levels of pollutants to mortality and morbidity (concentration-response relationships) and (ii) apply unit economic values. Cost of air pollution associated with passenger vehicles running over a major traffic bridge (6th of October Elevated Highway) is presented as a case study to demonstrate the use of monetary value of air pollution. The study proves that the cost of air pollution is extremely high and should not be overlooked.

Combustion Efficiency, Flameout Operability Limits and General Design Optimization for Integrated Ramjet-Scramjet Hypersonic Vehicles

NASA Astrophysics Data System (ADS)

Mbagwu, Chukwuka Chijindu

High speed, air-breathing hypersonic vehicles encounter a varied range of engine and operating conditions traveling along cruise/ascent missions at high altitudes and dynamic pressures. Variations of ambient pressure, temperature, Mach number, and dynamic pressure can affect the combustion conditions in conflicting ways. Computations were performed to understand propulsion tradeoffs that occur when a hypersonic vehicle travels along an ascent trajectory. Proper Orthogonal Decomposition methods were applied for the reduction of flamelet chemistry data in an improved combustor model. Two operability limits are set by requirements that combustion efficiency exceed selected minima and flameout be avoided. A method for flameout prediction based on empirical Damkohler number measurements is presented. Operability limits are plotted that define allowable flight corridors on an altitude versus flight Mach number performance map; fixed-acceleration ascent trajectories were considered for this study. Several design rules are also presented for a hypersonic waverider with a dual-mode scramjet engine. Focus is placed on ''vehicle integration" design, differing from previous ''propulsion-oriented" design optimization. The well-designed waverider falls between that of an aircraft (high lift-to-drag ratio) and a rocket (high thrust-to-drag ratio). 84 variations of an X-43-like vehicle were run using the MASIV scramjet reduced order model to examine performance tradeoffs. Informed by the vehicle design study, variable-acceleration trajectory optimization was performed for three constant dynamic pressures ascents. Computed flameout operability limits were implemented as additional constraints to the optimization problem. The Michigan-AFRL Scramjet In-Vehicle (MASIV) waverider model includes finite-rate chemistry, applied scaling laws for 3-D turbulent mixing, ram-scram transition and an empirical value of the flameout Damkohler number. A reduced-order modeling approach is justified

Planar air-bearing microgravity simulators: Review of applications, existing solutions and design parameters

NASA Astrophysics Data System (ADS)

Rybus, Tomasz; Seweryn, Karol

2016-03-01

All devices designed to be used in space must be thoroughly tested in relevant conditions. For several classes of devices the reduced gravity conditions are the key factor. In early stages of development and later due to financial reasons, the tests need to be done on Earth. However, in Earth conditions it is impossible to obtain a different gravity field independent on all linear and rotational spatial coordinates. Therefore, various test-bed systems are used, with their design driven by the device's specific needs. One of such test-beds are planar air-bearing microgravity simulators. In such an approach, the tested objects (e.g., manipulators intended for on-orbit operations or vehicles simulating satellites in a close formation flight) are mounted on planar air-bearings that allow almost frictionless motion on a flat surface, thus simulating microgravity conditions in two dimensions. In this paper we present a comprehensive review of research activities related to planar air-bearing microgravity simulators, demonstrating achievements of the most active research groups and describing newest trends and ideas, such as tests of landing gears for low-g bodies. Major design parameters of air-bearing test-beds are also reviewed and a list of notable existing test-beds is presented.

Assessing the Future Vehicle Fleet Electrification: The Impacts on Regional and Urban Air Quality.

PubMed

Ke, Wenwei; Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wang, Shuxiao; Hao, Jiming

2017-01-17

There have been significant advancements in electric vehicles (EVs) in recent years. However, the different changing patterns in emissions at upstream and on-road stages and complex atmospheric chemistry of pollutants lead to uncertainty in the air quality benefits from fleet electrification. This study considers the Yangtze River Delta (YRD) region in China to investigate whether EVs can improve future air quality. The Community Multiscale Air Quality model enhanced by the two-dimensional volatility basis set module is applied to simulate the temporally, spatially, and chemically resolved changes in PM 2.5 concentrations and the changes of other pollutants from fleet electrification. A probable scenario (Scenario EV1) with 20% of private light-duty passenger vehicles and 80% of commercial passenger vehicles (e.g., taxis and buses) electrified can reduce average PM 2.5 concentrations by 0.4 to 1.1 μg m -3 during four representative months for all urban areas of YRD in 2030. The seasonal distinctions of the air quality impacts with respect to concentration reductions in key aerosol components are also identified. For example, the PM 2.5 reduction in January is mainly attributed to the nitrate reduction, whereas the secondary organic aerosol reduction is another essential contributor in August. EVs can also effectively assist in mitigating NO 2 concentrations, which would gain greater reductions for traffic-dense urban areas (e.g., Shanghai). This paper reveals that the fleet electrification in the YRD region could generally play a positive role in improving regional and urban air quality.

The influence of air bags and restraining devices on extremity injuries in motor vehicle collisions.

PubMed

McGovern, M K; Murphy, R X; Okunski, W J; Wasser, T E

2000-05-01

The influence of air bags and other restraining devices on injury after motor vehicle collisions is not well defined. This study examined the relationship between the use of restraining devices and the incidence of extremity injuries in motor vehicle collisions. A retrospective analysis was performed on motor vehicle collision data submitted to the Pennsylvania Trauma Outcome Study database from 1990 through 1995. Criteria for submission included trauma patients who were admitted to the intensive care unit, who died during hospitalization, who were hospitalized for more than 72 hours, or who were transferred in or out of the receiving hospital. A total of 21,875 patients met these criteria. These patients were analyzed for the presence or absence of upper and lower extremity injuries and were compared based on their use of restraining devices. Restraining devices were categorized into four groups: air bag alone, air bag and seat belt, seat belt or carseat without air bag, and no restraining device. Statistical analysis was performed using the chi-squared test of association. For contingency tables with small expected frequencies, Fisher's exact test was used. Study participants included 11,688 men and 10,185 women with a mean age of 38 +/- 20 years. There were 16,033 drivers and 5,842 passengers. Air bags were deployed in 472 instances. In 297 of these cases, additional restraint was provided with a seat belt. In 6,632 cases, air bags were not deployed; however, patients were restrained with either a seat belt or a carseat. In 14,771 cases, patients were not restrained. When comparing restraining devices as a group vs. no restraint, there was a significant decrease in the incidence of upper (p = 0.018) and lower (p < 0.001) extremity injuries. Air bags, however, were associated with an increased incidence of both upper (p = 0.033) and lower (p = 0.002) extremity injuries when compared with no restraint or when compared among patients who were restrained. As a group

Affordable Flight Demonstration of the GTX Air-Breathing SSTO Vehicle Concept

NASA Technical Reports Server (NTRS)

Krivanek, Thomas M.; Roche, Joseph M.; Riehl, John P.; Kosareo, Daniel N.

2002-01-01

The rocket based combined cycle (RBCC) powered single-stage-to-orbit (SSTO) reusable launch vehicle has the potential to significantly reduce the total cost per pound for orbital payload missions. To validate overall system performance, a flight demonstration must be performed. This paper presents an overview of the first phase of a flight demonstration program for the GTX SSTO vehicle concept. Phase 1 will validate the propulsion performance of the vehicle configuration over the supersonic and hypersonic airbreathing portions of the trajectory. The focus and goal of Phase 1 is to demonstrate the integration and performance of the propulsion system flowpath with the vehicle aerodynamics over the air-breathing trajectory. This demonstrator vehicle will have dual mode ramjet/scramjets, which include the inlet, combustor, and nozzle with geometrically scaled aerodynamic surface outer mold lines (OML) defining the forebody, boundary layer diverter, wings, and tail. The primary objective of this study is to demonstrate propulsion system performance and operability including the ram to scram transition, as well as to validate vehicle aerodynamics and propulsion airframe integration. To minimize overall risk and development cost the effort will incorporate proven materials, use existing turbomachinery in the propellant delivery systems, launch from an existing unmanned remote launch facility, and use basic vehicle recovery techniques to minimize control and landing requirements. A second phase would demonstrate propulsion performance across all critical portions of a space launch trajectory (lift off through transition to all-rocket) integrated with flight-like vehicle systems.

Defining Support Requirements During Conceptual Design of Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Morris, W. D.; White, N. H.; Davis, W. T.; Ebeling, C. E.

1995-01-01

Current methods for defining the operational support requirements of new systems are data intensive and require significant design information. Methods are being developed to aid in the analysis process of defining support requirements for new launch vehicles during their conceptual design phase that work with the level of information available during this phase. These methods will provide support assessments based on the vehicle design and the operating scenarios. The results can be used both to define expected support requirements for new launch vehicle designs and to help evaluate the benefits of using new technologies. This paper describes the models, their current status, and provides examples of their use.

Advanced control design for hybrid turboelectric vehicle

NASA Technical Reports Server (NTRS)

Abban, Joseph; Norvell, Johnesta; Momoh, James A.

1995-01-01

The new environment standards are a challenge and opportunity for industry and government who manufacture and operate urban mass transient vehicles. A research investigation to provide control scheme for efficient power management of the vehicle is in progress. Different design requirements using functional analysis and trade studies of alternate power sources and controls have been performed. The design issues include portability, weight and emission/fuel efficiency of induction motor, permanent magnet and battery. A strategic design scheme to manage power requirements using advanced control systems is presented. It exploits fuzzy logic, technology and rule based decision support scheme. The benefits of our study will enhance the economic and technical feasibility of technological needs to provide low emission/fuel efficient urban mass transit bus. The design team includes undergraduate researchers in our department. Sample results using NASA HTEV simulation tool are presented.

Development of vehicle magnetic air conditioner (VMAC) technology. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gschneidner, Karl A., Jr.; Pecharsky, V.K.; Jiles, David

2001-08-28

The objective of Phase I was to explore the feasibility of the development of a new solid state refrigeration technology - magnetic refrigeration - in order to reduce power consumption of a vehicle air conditioner by 30%. The feasibility study was performed at Iowa State University (ISU) together with Astronautics Corporation of America Technology Center (ACATC), Madison, WI, through a subcontract with ISU.

The ironies of vehicle feedback in car design.

PubMed

Walker, Guy H; Stanton, Neville A; Young, Mark S

2006-02-10

Car drivers show an acute sensitivity towards vehicle feedback, with most normal drivers able to detect 'the difference in vehicle feel of a medium-size saloon car with and without a fairly heavy passenger in the rear seat' (Joy and Hartley 1953-54). The irony is that this level of sensitivity stands in contrast to the significant changes in vehicle 'feel' accompanying modern trends in automotive design, such as drive-by-wire and increased automation. The aim of this paper is to move the debate from the anecdotal to the scientific level. This is achieved by using the Brunel University driving simulator to replicate some of these trends and changes by presenting (or removing) different forms of non-visual vehicle feedback, and measuring resultant driver situational awareness (SA) using a probe-recall method. The findings confirm that vehicle feedback plays a key role in coupling the driver to the dynamics of their environment (Moray 2004), with the role of auditory feedback particularly prominent. As a contrast, drivers in the study also rated their self-perceived levels of SA and a concerning dissociation occurred between the two sets of results. Despite the large changes in vehicle feedback presented in the simulator, and the measured changes in SA, drivers appeared to have little self-awareness of these changes. Most worryingly, drivers demonstrated little awareness of diminished SA. The issues surrounding vehicle feedback are therefore similar to the classic problems and ironies studied in aviation and automation, and highlight the role that ergonomics can also play within the domain of contemporary vehicle design.

Launch Vehicle Design Process Description and Training Formulation

NASA Technical Reports Server (NTRS)

Atherton, James; Morris, Charles; Settle, Gray; Teal, Marion; Schuerer, Paul; Blair, James; Ryan, Robert; Schutzenhofer, Luke

1999-01-01

A primary NASA priority is to reduce the cost and improve the effectiveness of launching payloads into space. As a consequence, significant improvements are being sought in the effectiveness, cost, and schedule of the launch vehicle design process. In order to provide a basis for understanding and improving the current design process, a model has been developed for this complex, interactive process, as reported in the references. This model requires further expansion in some specific design functions. Also, a training course for less-experienced engineers is needed to provide understanding of the process, to provide guidance for its effective implementation, and to provide a basis for major improvements in launch vehicle design process technology. The objective of this activity is to expand the description of the design process to include all pertinent design functions, and to develop a detailed outline of a training course on the design process for launch vehicles for use in educating engineers whose experience with the process has been minimal. Building on a previously-developed partial design process description, parallel sections have been written for the Avionics Design Function, the Materials Design Function, and the Manufacturing Design Function. Upon inclusion of these results, the total process description will be released as a NASA TP. The design function sections herein include descriptions of the design function responsibilities, interfaces, interactive processes, decisions (gates), and tasks. Associated figures include design function planes, gates, and tasks, along with other pertinent graphics. Also included is an expanded discussion of how the design process is divided, or compartmentalized, into manageable parts to achieve efficient and effective design. A detailed outline for an intensive two-day course on the launch vehicle design process has been developed herein, and is available for further expansion. The course is in an interactive lecture

Control-Relevant Modeling, Analysis, and Design for Scramjet-Powered Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Rodriguez, Armando A.; Dickeson, Jeffrey J.; Sridharan, Srikanth; Benavides, Jose; Soloway, Don; Kelkar, Atul; Vogel, Jerald M.

2009-01-01

Within this paper, control-relevant vehicle design concepts are examined using a widely used 3 DOF (plus flexibility) nonlinear model for the longitudinal dynamics of a generic carrot-shaped scramjet powered hypersonic vehicle. Trade studies associated with vehicle/engine parameters are examined. The impact of parameters on control-relevant static properties (e.g. level-flight trimmable region, trim controls, AOA, thrust margin) and dynamic properties (e.g. instability and right half plane zero associated with flight path angle) are examined. Specific parameters considered include: inlet height, diffuser area ratio, lower forebody compression ramp inclination angle, engine location, center of gravity, and mass. Vehicle optimizations is also examined. Both static and dynamic considerations are addressed. The gap-metric optimized vehicle is obtained to illustrate how this control-centric concept can be used to "reduce" scheduling requirements for the final control system. A classic inner-outer loop control architecture and methodology is used to shed light on how specific vehicle/engine design parameter selections impact control system design. In short, the work represents an important first step toward revealing fundamental tradeoffs and systematically treating control-relevant vehicle design.

The second X-45A Unmanned Combat Air Vehicle (UCAV) technology demonstrator aircraft during its maiden flight. The flight marks another milestone for the UCAV program, and verified the aircraft's flight control software

NASA Image and Video Library

2002-11-21

The second X-45A Unmanned Combat Air Vehicle (UCAV) technology demonstrator completed its first flight on November 21, 2002, after taking off from a dry lakebed at NASA's Dryden Flight Research Center, Edwards Air Force Base, California. X-45A vehicle two flew for approximately 30 minutes and reached an airspeed of 195 knots and an altitude of 7500 feet. This flight validated the functionality of the UCAV flight software on the second air vehicle. Dryden is supporting the DARPA/Boeing team in the design, development, integration, and demonstration of the critical technologies, processes, and system attributes leading to an operational UCAV system. Dryden support of the X-45A demonstrator system includes analysis, component development, simulations, ground and flight tests.

Design Considerations for a Launch Vehicle Development Flight Instrumentation System

NASA Technical Reports Server (NTRS)

Johnson, Martin L.; Crawford, Kevin

2011-01-01

When embarking into the design of a new launch vehicle, engineering models of expected vehicle performance are always generated. While many models are well established and understood, some models contain design features that are only marginally known. Unfortunately, these analytical models produce uncertainties in design margins. The best way to answer these analytical issues is with vehicle level testing. The National Aeronautics and Space Administration respond to these uncertainties by using a vehicle level system called the Development Flight Instrumentation, or DFI. This DFI system can be simple to implement, with only a few measurements, or it may be a sophisticated system with hundreds of measurement and video, without a recording capability. From experience with DFI systems, DFI never goes away. The system is renamed and allowed to continue, in most cases. Proper system design can aid the transition to future data requirements. This paper will discuss design features that need to be considered when developing a DFI system for a launch vehicle. It will briefly review the data acquisition units, sensors, multiplexers and recorders, telemetry components and harnessing. It will present a reasonable set of requirements which should be implemented in the beginning of the program in order to start the design. It will discuss a simplistic DFI architecture that could be the basis for the next NASA launch vehicle. This will be followed by a discussion of the "experiences gained" from a past DFI system implementation, such as the very successful Ares I-X test flight. Application of these design considerations may not work for every situation, but they may direct a path toward success or at least make one pause and ask the right questions.

Design and development of an unconventional VTOL micro air vehicle: The Cyclocopter

NASA Astrophysics Data System (ADS)

Benedict, Moble; Chopra, Inderjit

2012-06-01

This paper discusses the systematic experimental and vehicle design/development studies conducted at the University of Maryland which culminated in the development of the first flying Cyclocopter in the history. Cyclocopter is a novel Vertical Take-Off and Landing (VTOL) aircraft, which utilizes cycloidalrotors (cyclorotors), a revolutionary horizontal axis propulsion concept, that has many advantages such as higher aerodynamic efficiency, maneuverability and high-speed forward flight capability when compared to a conventional helicopter rotor. The experimental studies included a detailed parametric study to understand the effect of rotor geometry and blade kinematics on cyclorotor hover performance. Based on the experimental results, higher blade pitch angles were found to improve thrust and increase the power loading (thrust per unit power) of the cyclorotor. Asymmetric pitching with higher pitch angle at the top than at the bottom produced better power loading. The chordwise optimum pitching axis location was observed to be around 25-35% of the blade chord. Because of the flow curvature effects, the cycloidal rotor performance was a strong function of the chord/radius ratio. The optimum chord/radius ratios were extremely high, around 0.5-0.8, depending on the blade pitching amplitude. A flow field investigation was also conducted using Particle Image Velocimetry (PIV) to unravel the physics behind thrust production of a cyclorotor. PIV studies indicated evidence of a stall delay as well as possible increases in lift on the blades from the presence of a leading edge vortex. The goal of all these studies was to understand and optimize the performance of a micro-scale cyclorotor so that it could be used in a flying vehicle. An optimized cyclorotor was used to develop a 200 gram cyclocopter capable of autonomous stable hover using an onboard feedback controller.

Flexible Wing Base Micro Aerial Vehicles: Towards Flight Autonomy: Vision-Based Horizon Detection for Micro Air Vehicles

NASA Technical Reports Server (NTRS)

Nechyba, Michael C.; Ettinger, Scott M.; Ifju, Peter G.; Wazak, Martin

2002-01-01

Recently substantial progress has been made towards design building and testifying remotely piloted Micro Air Vehicles (MAVs). This progress in overcoming the aerodynamic obstacles to flight at very small scales has, unfortunately, not been matched by similar progress in autonomous MAV flight. Thus, we propose a robust, vision-based horizon detection algorithm as the first step towards autonomous MAVs. In this paper, we first motivate the use of computer vision for the horizon detection task by examining the flight of birds (biological MAVs) and considering other practical factors. We then describe our vision-based horizon detection algorithm, which has been demonstrated at 30 Hz with over 99.9% correct horizon identification, over terrain that includes roads, buildings large and small, meadows, wooded areas, and a lake. We conclude with some sample horizon detection results and preview a companion paper, where the work discussed here forms the core of a complete autonomous flight stability system.

CRITERIA AND AIR TOXIC EMISSIONS FROM IN-USE, LOW EMISSION VEHICLES (LEVS)

EPA Science Inventory

The U.S. Environmental Protection Agency implemented a program to identify tailpipe emissions of criteria and air toxic contaminants from in-use, light-duty Low Emission Vehicles (LEVs). EPA recruited twenty-five LEVs in 2002, and measured emissions on a chassis dynamometer usin...

A review of compliant transmission mechanisms for bio-inspired flapping-wing micro air vehicles.

PubMed

Zhang, C; Rossi, C

2017-02-15

Flapping-wing micro air vehicles (FWMAVs) are a class of unmanned aircraft that imitate flight characteristics of natural organisms such as birds, bats, and insects, in order to achieve maximum flight efficiency and manoeuvrability. Designing proper mechanisms for flapping transmission is an extremely important aspect for FWMAVs. Compliant transmission mechanisms have been considered as an alternative to rigid transmission systems due to their lower the number of parts, thereby reducing the total weight, lower energy loss thanks to little or practically no friction among parts, and at the same time, being able to store and release mechanical power during the flapping cycle. In this paper, the state-of-the-art research in this field is dealt upon, highlighting open challenges and research topics. An optimization method for designing compliant transmission mechanisms inspired by the thoraxes of insects is also introduced.

Vehicle performance impact on space shuttle design and concept evaluation

NASA Technical Reports Server (NTRS)

Craig, M. K.

1972-01-01

The continuing examination of widely varied space shuttle concepts makes an understanding of concept interaction with vehicle performance imperative. The estimation of vehicle performance is highly appurtenant to all aspects of shuttle design and hence performance has classically been a key indicator of overall concept desirability and potential. Vehicle performance assumes the added role of defining interactions between specific design characteristics, the sum total of which define a specific concept. Special attention is given to external tank effects.

Absorbable energy monitoring scheme: new design protocol to test vehicle structural crashworthiness.

PubMed

Ofochebe, Sunday M; Enibe, Samuel O; Ozoegwu, Chigbogu G

2016-05-01

In vehicle crashworthiness design optimization detailed system evaluation capable of producing reliable results are basically achieved through high-order numerical computational (HNC) models such as the dynamic finite element model, mesh-free model etc. However the application of these models especially during optimization studies is basically challenged by their inherent high demand on computational resources, conditional stability of the solution process, and lack of knowledge of viable parameter range for detailed optimization studies. The absorbable energy monitoring scheme (AEMS) presented in this paper suggests a new design protocol that attempts to overcome such problems in evaluation of vehicle structure for crashworthiness. The implementation of the AEMS involves studying crash performance of vehicle components at various absorbable energy ratios based on a 2DOF lumped-mass-spring (LMS) vehicle impact model. This allows for prompt prediction of useful parameter values in a given design problem. The application of the classical one-dimensional LMS model in vehicle crash analysis is further improved in the present work by developing a critical load matching criterion which allows for quantitative interpretation of the results of the abstract model in a typical vehicle crash design. The adequacy of the proposed AEMS for preliminary vehicle crashworthiness design is demonstrated in this paper, however its extension to full-scale design-optimization problem involving full vehicle model that shows greater structural detail requires more theoretical development.

Phase 1 of the near team hybrid passenger vehicle development program. Appendix C: Preliminary design data package. Volume 2: Appendices

NASA Technical Reports Server (NTRS)

Piccolo, R.

1979-01-01

The design, development, efficiency, manufacturability, production costs, life cycle cost, and safety of sodium-sulfur, nickel-zinc, and lead-acid batteries for electric hybrid vehicles are discussed. Models are given for simulating the vehicle handling quality, and for finding the value of: (1) the various magnetic quantities in the different sections in which the magnetic circuit of the DC electric machine is divided; (2) flux distribution in the air gap and the magnetization curve under load conditions; and (3) the mechanical power curves versus motor speed at different values of armature current.

Cabin air temperature of parked vehicles in summer conditions: life-threatening environment for children and pets calculated by a dynamic model

NASA Astrophysics Data System (ADS)

Horak, Johannes; Schmerold, Ivo; Wimmer, Kurt; Schauberger, Günther

2017-10-01

In vehicles that are parked, no ventilation and/or air conditioning takes place. If a vehicle is exposed to direct solar radiation, an immediate temperature rise occurs. The high cabin air temperature can threaten children and animals that are left unattended in vehicles. In the USA, lethal heat strokes cause a mean death rate of 37 children per year. In addition, temperature-sensitive goods (e.g. drugs in ambulances and veterinary vehicles) can be adversely affected by high temperatures. To calculate the rise of the cabin air temperature, a dynamic model was developed that is driven by only three parameters, available at standard meteorological stations: air temperature, global radiation and wind velocity. The transition from the initial temperature to the constant equilibrium temperature depends strongly on the configuration of the vehicle, more specifically on insulation, window area and transmission of the glass, as well as on the meteorological conditions. The comparison of the model with empirical data showed good agreement. The model output can be applied to assess the heat load of children and animals as well as temperature-sensitive goods, which are transported and/or stored in a vehicle.

Preliminary design data package, appendix C. [hybrid electric vehicles

NASA Technical Reports Server (NTRS)

1979-01-01

The data and documentation required to define the preliminary design of a near term hybrid vehicle and to quantify its operational characteristics are presented together with the assumptions and rationale behind the design decisions. Aspects discussed include development requirements for the propulsion system, the chassis system, the body, and the vehicle systems. Particular emphasis is given to the controls, the heat engine, and the batteries.

Study on energy saving effect of IHX on vehicle air conditioning system

NASA Astrophysics Data System (ADS)

Li, Huguang; Tong, Lin; Xu, Ming; Wei, Wangrui; Zhao, Meng; Wang, Long

2018-02-01

In this paper, the performance of Internal Heat Exchanger (IHX) air conditioning system for R134a is investigated in bench test and vehicle test. Comparison for cooling capacity and energy consumption between IHX air conditioning system and traditional tube air conditioning system are conducted. The suction temperature and discharge temperature of compressor is also recorded. The results show that IHX air conditioning system has higher cooling capacity, the vent temperature decrease 2.3 °C in idle condition. But the suction temperature and discharge temperature of compressor increase 10°C. IHX air conditioning system has lower energy consumption than traditional tube air conditioning system. Under the experimental conditions in this paper, the application of IHX can significantly reduce the energy consumption of air conditioning system. At 25°C of environment temperature, AC system energy consumption decrease 14%, compressor energy consumption decrease 16%. At 37°C of environment temperature, AC system energy consumption decrease 16%, compressor energy consumption decrease 13%.

Canadair CL-227 Remotely Piloted Vehicle

NASA Astrophysics Data System (ADS)

Clark, Andrew S.

1983-08-01

The Canadair CL-227 is a rotary winged Remotely Piloted Vehicle (RPV) intended initially as the air-vehicle for a medium range battlefield surveillance and target acquisition system. The concept on which this vehicle is based brings together in-house expertise as a designer and manufacturer of surveillance drones (AN-USD-50l -MIDGE-) with experience in rigid rotor technology from the CL-84 tilt wing VTOL program. The vehicle is essentially modular in design with a power module containing the engine, fuel and related systems, a rotor module containing the two counter-rotating rotors and control actuators, and a control module containing the autopilot, data link and sensor system. The vehicle is a true RPV (as opposed to a drone) as it is flown in real time by an operator on the ground and requires relatively little skill to pilot.

Complex multidisciplinary systems decomposition for aerospace vehicle conceptual design and technology acquisition

NASA Astrophysics Data System (ADS)

Omoragbon, Amen

Although, the Aerospace and Defense (A&D) industry is a significant contributor to the United States' economy, national prestige and national security, it experiences significant cost and schedule overruns. This problem is related to the differences between technology acquisition assessments and aerospace vehicle conceptual design. Acquisition assessments evaluate broad sets of alternatives with mostly qualitative techniques, while conceptual design tools evaluate narrow set of alternatives with multidisciplinary tools. In order for these two fields to communicate effectively, a common platform for both concerns is desired. This research is an original contribution to a three-part solution to this problem. It discusses the decomposition step of an innovation technology and sizing tool generation framework. It identifies complex multidisciplinary system definitions as a bridge between acquisition and conceptual design. It establishes complex multidisciplinary building blocks that can be used to build synthesis systems as well as technology portfolios. It also describes a Graphical User Interface Designed to aid in decomposition process. Finally, it demonstrates an application of the methodology to a relevant acquisition and conceptual design problem posed by the US Air Force.

Status of ERA Vehicle System Integration Technology Demonstrators

NASA Technical Reports Server (NTRS)

Flamm, Jeffrey D.; Fernandez, Hamilton; Khorrami, Mehdi; James, Kevin D.; Thomas, Russell

2015-01-01

The Environmentally Responsible Aviation (ERA) Project within the Integrated Systems Research Program (ISRP) of the NASA Aeronautics Research Mission Directorate (ARMD) has the responsibility to explore and document the feasibility, benefits, and technical risk of air vehicle concepts and enabling technologies that will reduce the impact of aviation on the environment. The primary goal of the ERA Project is to select air vehicle concepts and technologies that can simultaneously reduce fuel burn, noise, and emissions. In addition, the ERA Project will identify and mitigate technical risk and transfer knowledge to the aeronautics community at large so that new technologies and vehicle concepts can be incorporated into the future design of aircraft.

Improved LTVMPC design for steering control of autonomous vehicle

NASA Astrophysics Data System (ADS)

Velhal, Shridhar; Thomas, Susy

2017-01-01

An improved linear time varying model predictive control for steering control of autonomous vehicle running on slippery road is presented. Control strategy is designed such that the vehicle will follow the predefined trajectory with highest possible entry speed. In linear time varying model predictive control, nonlinear vehicle model is successively linearized at each sampling instant. This linear time varying model is used to design MPC which will predict the future horizon. By incorporating predicted input horizon in each successive linearization the effectiveness of controller has been improved. The tracking performance using steering with front wheel and braking at four wheels are presented to illustrate the effectiveness of the proposed method.

Function-based design process for an intelligent ground vehicle vision system

NASA Astrophysics Data System (ADS)

Nagel, Robert L.; Perry, Kenneth L.; Stone, Robert B.; McAdams, Daniel A.

2010-10-01

An engineering design framework for an autonomous ground vehicle vision system is discussed. We present both the conceptual and physical design by following the design process, development and testing of an intelligent ground vehicle vision system constructed for the 2008 Intelligent Ground Vehicle Competition. During conceptual design, the requirements for the vision system are explored via functional and process analysis considering the flows into the vehicle and the transformations of those flows. The conceptual design phase concludes with a vision system design that is modular in both hardware and software and is based on a laser range finder and camera for visual perception. During physical design, prototypes are developed and tested independently, following the modular interfaces identified during conceptual design. Prototype models, once functional, are implemented into the final design. The final vision system design uses a ray-casting algorithm to process camera and laser range finder data and identify potential paths. The ray-casting algorithm is a single thread of the robot's multithreaded application. Other threads control motion, provide feedback, and process sensory data. Once integrated, both hardware and software testing are performed on the robot. We discuss the robot's performance and the lessons learned.

Flexible Wing Base Micro Aerial Vehicles: Vision-Guided Flight Stability and Autonomy for Micro Air Vehicles

NASA Technical Reports Server (NTRS)

Ettinger, Scott M.; Nechyba, Michael C.; Ifju, Peter G.; Wazak, Martin

2002-01-01

Substantial progress has been made recently towards design building and test-flying remotely piloted Micro Air Vehicle's (MAVs). We seek to complement this progress in overcoming the aerodynamic obstacles to.flight at very small scales with a vision stability and autonomy system. The developed system based on a robust horizon detection algorithm which we discuss in greater detail in a companion paper. In this paper, we first motivate the use of computer vision for MAV autonomy arguing that given current sensor technology, vision may he the only practical approach to the problem. We then briefly review our statistical vision-based horizon detection algorithm, which has been demonstrated at 30Hz with over 99.9% correct horizon identification. Next we develop robust schemes for the detection of extreme MAV attitudes, where no horizon is visible, and for the detection of horizon estimation errors, due to external factors such as video transmission noise. Finally, we discuss our feed-back controller for self-stabilized flight, and report results on vision autonomous flights of duration exceeding ten minutes.

Association between side air bags and risk of injury in motor vehicle collisions with near-side impact.

PubMed

McGwin, Gerald; Metzger, Jesse; Porterfield, John R; Moran, Stephan G; Rue, Loring W

2003-09-01

Side air bags (SABs) have been introduced in an attempt to reduce the risk of injury in near-side-impact motor vehicle collisions (MVCs). The impact of SABs on MVC-related mortality and morbidity has yet to be evaluated with a large population-based study. The objective of this study was to assess the effectiveness of SABs in reducing the risk of injury or death in near-side-impact MVCs. A retrospective study investigated outboard front seat occupants involved in police-reported, near-side-impact MVCs using data from the General Estimates System (1997-2000). The risk of MVC-related nonfatal and fatal injury for occupants of vehicles with and without SABs was compared. Front seat occupants of vehicles with SABs had a risk of injury similar to that of occupants of vehicles without SABs (risk ratio [RR], 0.96; 95% CI confidence interval [CI], 0.79-1.15). Adjustment for the potentially confounding effects of age, gender, seat belt use, seating position, damage severity and location, and vehicle body type did not meaningfully affect the association (RR, 0.90; 95% CICI, 0.76-1.08). There is no association between the availability of SABs and overall injury risk in near-side-impact MVCs. Future research is necessary to determine the effectiveness of SABs in preventing the injuries for which they were specifically designed.

Kistler reusable vehicle facility design and operational approach

NASA Astrophysics Data System (ADS)

Fagan, D.; McInerney, F.; Johnston, C.; Tolson, B.

Kistler Aerospace Corporation is designing and developing the K-1, the world's first fully reusable aerospace vehicle to deliver satellites into orbit. The K-1 vehicle test program will be conducted in Woomera, Australia, with commercial operations scheduled to begin shortly afterwards. Both stages of the K-1 will return to the launch site utilizing parachutes and airbags for a soft landing within 24 h after launch. The turnaround flow of the two stages will cycle from landing site to a maintenance/refurbishment facility and through the next launch in only 9 days. Payload processing will occur in a separate facility in parallel with recovery and refurbishment operations. The vehicle design and on-board checkout capability of the avionics system eliminates the need for an abundance of ground checkout equipment. Payload integration, vehicle assembly, and K-1 transport to the launch pad will be performed horizontally, simplifying processing and reducing infrastructure requirements. This simple, innovative, and cost-effective approach will allow Kistler to offer its customers flexible, low-cost, and on-demand launch services.

Survey of Sliding Contact/Solid Rail Power Collection Systems for Application to the Tracked Air Cushion Vehicle

DOT National Transportation Integrated Search

1971-01-01

The objective of a power collection system is to deliver uninterrupted power from the wayside to a vehicle. In order to apply the third rail concept, used for subway power collection, to the tracked air cushion vehicle, considerable improvement must ...

Nuclear Electric Vehicle Optimization Toolset (NEVOT): Integrated System Design Using Genetic Algorithms

NASA Technical Reports Server (NTRS)

Tinker, Michael L.; Steincamp, James W.; Stewart, Eric T.; Patton, Bruce W.; Pannell, William P.; Newby, Ronald L.; Coffman, Mark E.; Qualls, A. L.; Bancroft, S.; Molvik, Greg

2003-01-01

The Nuclear Electric Vehicle Optimization Toolset (NEVOT) optimizes the design of all major Nuclear Electric Propulsion (NEP) vehicle subsystems for a defined mission within constraints and optimization parameters chosen by a user. The tool uses a Genetic Algorithm (GA) search technique to combine subsystem designs and evaluate the fitness of the integrated design to fulfill a mission. The fitness of an individual is used within the GA to determine its probability of survival through successive generations in which the designs with low fitness are eliminated and replaced with combinations or mutations of designs with higher fitness. The program can find optimal solutions for different sets of fitness metrics without modification and can create and evaluate vehicle designs that might never be conceived of through traditional design techniques. It is anticipated that the flexible optimization methodology will expand present knowledge of the design trade-offs inherent in designing nuclear powered space vehicles and lead to improved NEP designs.

Closed-Loop Control of Constrained Flapping Wing Micro Air Vehicles

DTIC Science & Technology

2014-03-27

insects , thus concealing their appearance while also providing benefits of unsteady aerodynamics. Consider- able research has been invested in the...small visibility signature that tends to hide in plain sight by resembling insects . 1.2 Research Challenges for Flapping Wing Micro Air Vehicles There are...predicts forces and moments for the class of flapping wing fliers that makes up most insects and hummingbirds. Large bird and butterfly “clap- and

Near-term hybrid vehicle program, phase 1. Appendix C: Preliminary design data package

NASA Technical Reports Server (NTRS)

1979-01-01

The design methodology, the design decision rationale, the vehicle preliminary design summary, and the advanced technology developments are presented. The detailed vehicle design, the vehicle ride and handling and front structural crashworthiness analysis, the microcomputer control of the propulsion system, the design study of the battery switching circuit, the field chopper, and the battery charger, and the recent program refinements and computer results are presented.

Final Approval of California Air Plan Revision; Antelope Valley Air Quality Management District; VOCs From Motor Vehicle Assembly Coating Operations

EPA Pesticide Factsheets

EPA is taking final action to approve a revision to the Antelope Valley Air Quality Management District (AVAQMD) portion of the California SIP concerning the emissions of volatile organic compounds (VOCs) from motor vehicle assembly coating operations.

Complex multidisciplinary system composition for aerospace vehicle conceptual design

NASA Astrophysics Data System (ADS)

Gonzalez, Lex

Generic Hypersonic Vehicle (GHV), an open source family of hypersonic vehicles originating from the Air Force Research Laboratory. AVDDBMS has been applied in three different ways in order to assess its validity: Verification using GHV disciplinary data, Validation using selected disciplinary analysis methods, and Application of the CMDS Composition Process to assess the design solution space for the GHV hardware. The research demonstrates the holistic effect that selection of individual disciplinary analysis methods has on the structure and integration of the analysis framework.

Simulation of Wind Profile Perturbations for Launch Vehicle Design

NASA Technical Reports Server (NTRS)

Adelfang, S. I.

2004-01-01

Ideally, a statistically representative sample of measured high-resolution wind profiles with wavelengths as small as tens of meters is required in design studies to establish aerodynamic load indicator dispersions and vehicle control system capability. At most potential launch sites, high- resolution wind profiles may not exist. Representative samples of Rawinsonde wind profiles to altitudes of 30 km are more likely to be available from the extensive network of measurement sites established for routine sampling in support of weather observing and forecasting activity. Such a sample, large enough to be statistically representative of relatively large wavelength perturbations, would be inadequate for launch vehicle design assessments because the Rawinsonde system accurately measures wind perturbations with wavelengths no smaller than 2000 m (1000 m altitude increment). The Kennedy Space Center (KSC) Jimsphere wind profiles (150/month and seasonal 2 and 3.5-hr pairs) are the only adequate samples of high resolution profiles approx. 150 to 300 m effective resolution, but over-sampled at 25 m intervals) that have been used extensively for launch vehicle design assessments. Therefore, a simulation process has been developed for enhancement of measured low-resolution Rawinsonde profiles that would be applicable in preliminary launch vehicle design studies at launch sites other than KSC.

Environmental Controls and Life Support System Design for a Space Exploration Vehicle

NASA Technical Reports Server (NTRS)

Stambaugh, Imelda C.; Rodriguez, Branelle; Vonau, Walt, Jr.; Borrego, Melissa

2012-01-01

Engineers at Johnson Space Center (JSC) are developing an Environmental Control and Life Support System (ECLSS) design for the Space Exploration Vehicle (SEV). The SEV will aid to expand the human exploration envelope for Geostationary Transfer Orbit (GEO), Near Earth Object (NEO), or planetary missions by using pressurized surface exploration vehicles. The SEV, formerly known as the Lunar Electric Rover (LER), will be an evolutionary design starting as a ground test prototype where technologies for various systems will be tested and evolve into a flight vehicle. This paper will discuss the current SEV ECLSS design, any work contributed toward the development of the ECLSS design, and the plan to advance the ECLSS design based on the SEV vehicle and system needs.

Study Design for a Method of Projecting Vehicle Miles of Travel

DOT National Transportation Integrated Search

1977-08-01

Vehicle miles of travel (VMT) by passenger automobiles is an important determinant of gasoline consumption, ambient air quality, highway safety, and personal and corporate financial conditions in the United States. Changing patterns and trends in VMT...

Information Flow in the Launch Vehicle Design/Analysis Process

NASA Technical Reports Server (NTRS)

Humphries, W. R., Sr.; Holland, W.; Bishop, R.

1999-01-01

This paper describes the results of a team effort aimed at defining the information flow between disciplines at the Marshall Space Flight Center (MSFC) engaged in the design of space launch vehicles. The information flow is modeled at a first level and is described using three types of templates: an N x N diagram, discipline flow diagrams, and discipline task descriptions. It is intended to provide engineers with an understanding of the connections between what they do and where it fits in the overall design process of the project. It is also intended to provide design managers with a better understanding of information flow in the launch vehicle design cycle.

Low Life Cycle Cost Design Study for Paratransit Vehicles

DOT National Transportation Integrated Search

1978-07-01

This report summarizes the work performed on the Low Life Cycle Cost (LLCC) paratransit vehicle contract. The program was structured to provide a design of a vehicle suitable for taxi paratransit usage and optimized for LLCC to the end user. This eff...

A Conceptual Aerospace Vehicle Structural System Modeling, Analysis and Design Process

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

2007-01-01

A process for aerospace structural concept analysis and design is presented, with examples of a blended-wing-body fuselage, a multi-bubble fuselage concept, a notional crew exploration vehicle, and a high altitude long endurance aircraft. Aerospace vehicle structures must withstand all anticipated mission loads, yet must be designed to have optimal structural weight with the required safety margins. For a viable systems study of advanced concepts, these conflicting requirements must be imposed and analyzed early in the conceptual design cycle, preferably with a high degree of fidelity. In this design process, integrated multidisciplinary analysis tools are used in a collaborative engineering environment. First, parametric solid and surface models including the internal structural layout are developed for detailed finite element analyses. Multiple design scenarios are generated for analyzing several structural configurations and material alternatives. The structural stress, deflection, strain, and margins of safety distributions are visualized and the design is improved. Over several design cycles, the refined vehicle parts and assembly models are generated. The accumulated design data is used for the structural mass comparison and concept ranking. The present application focus on the blended-wing-body vehicle structure and advanced composite material are also discussed.

A prototype computerized synthesis methodology for generic space access vehicle (SAV) conceptual design

NASA Astrophysics Data System (ADS)

Huang, Xiao

2006-04-01

Today's and especially tomorrow's competitive launch vehicle design environment requires the development of a dedicated generic Space Access Vehicle (SAV) design methodology. A total of 115 industrial, research, and academic aircraft, helicopter, missile, and launch vehicle design synthesis methodologies have been evaluated. As the survey indicates, each synthesis methodology tends to focus on a specific flight vehicle configuration, thus precluding the key capability to systematically compare flight vehicle design alternatives. The aim of the research investigation is to provide decision-making bodies and the practicing engineer a design process and tool box for robust modeling and simulation of flight vehicles where the ultimate performance characteristics may hinge on numerical subtleties. This will enable the designer of a SAV for the first time to consistently compare different classes of SAV configurations on an impartial basis. This dissertation presents the development steps required towards a generic (configuration independent) hands-on flight vehicle conceptual design synthesis methodology. This process is developed such that it can be applied to any flight vehicle class if desired. In the present context, the methodology has been put into operation for the conceptual design of a tourist Space Access Vehicle. The case study illustrates elements of the design methodology & algorithm for the class of Horizontal Takeoff and Horizontal Landing (HTHL) SAVs. The HTHL SAV design application clearly outlines how the conceptual design process can be centrally organized, executed and documented with focus on design transparency, physical understanding and the capability to reproduce results. This approach offers the project lead and creative design team a management process and tool which iteratively refines the individual design logic chosen, leading to mature design methods and algorithms. As illustrated, the HTHL SAV hands-on design methodology offers growth

Multidisciplinary Design Techniques Applied to Conceptual Aerospace Vehicle Design. Ph.D. Thesis Final Technical Report

NASA Technical Reports Server (NTRS)

Olds, John Robert; Walberg, Gerald D.

1993-01-01

Multidisciplinary design optimization (MDO) is an emerging discipline within aerospace engineering. Its goal is to bring structure and efficiency to the complex design process associated with advanced aerospace launch vehicles. Aerospace vehicles generally require input from a variety of traditional aerospace disciplines - aerodynamics, structures, performance, etc. As such, traditional optimization methods cannot always be applied. Several multidisciplinary techniques and methods were proposed as potentially applicable to this class of design problem. Among the candidate options are calculus-based (or gradient-based) optimization schemes and parametric schemes based on design of experiments theory. A brief overview of several applicable multidisciplinary design optimization methods is included. Methods from the calculus-based class and the parametric class are reviewed, but the research application reported focuses on methods from the parametric class. A vehicle of current interest was chosen as a test application for this research. The rocket-based combined-cycle (RBCC) single-stage-to-orbit (SSTO) launch vehicle combines elements of rocket and airbreathing propulsion in an attempt to produce an attractive option for launching medium sized payloads into low earth orbit. The RBCC SSTO presents a particularly difficult problem for traditional one-variable-at-a-time optimization methods because of the lack of an adequate experience base and the highly coupled nature of the design variables. MDO, however, with it's structured approach to design, is well suited to this problem. The result of the application of Taguchi methods, central composite designs, and response surface methods to the design optimization of the RBCC SSTO are presented. Attention is given to the aspect of Taguchi methods that attempts to locate a 'robust' design - that is, a design that is least sensitive to uncontrollable influences on the design. Near-optimum minimum dry weight solutions are

Steering Dynamics of Tilting Narrow Track Vehicle with Passive Front Wheel Design

NASA Astrophysics Data System (ADS)

TAN, Jeffrey Too Chuan; ARAKAWA, Hiroki; SUDA, Yoshihiro

2016-09-01

In recent years, narrow track vehicle has been emerged as a potential candidate for the next generation of urban transportation system, which is greener and space effective. Vehicle body tilting has been a symbolic characteristic of such vehicle, with the purpose to maintain its stability with the narrow track body. However, the coordination between active steering and vehicle tilting requires considerable driving skill in order to achieve effective stability. In this work, we propose an alternative steering method with a passive front wheel that mechanically follows the vehicle body tilting. The objective of this paper is to investigate the steering dynamics of the vehicle under various design parameters of the passive front wheel. Modeling of a three-wheel tilting narrow track vehicle and multibody dynamics simulations were conducted to study the effects of two important front wheel design parameters, i.e. caster angle and trail toward the vehicle steering dynamics in steering response time, turning radius, steering stability and resiliency towards external disturbance. From the results of the simulation studies, we have verified the relationships of these two front wheel design parameters toward the vehicle steering dynamics.

An optimal system design process for a Mars roving vehicle

NASA Technical Reports Server (NTRS)

Pavarini, C.; Baker, J.; Goldberg, A.

1971-01-01

The problem of determining the optimal design for a Mars roving vehicle is considered. A system model is generated by consideration of the physical constraints on the design parameters and the requirement that the system be deliverable to the Mars surface. An expression which evaluates system performance relative to mission goals as a function of the design parameters only is developed. The use of nonlinear programming techniques to optimize the design is proposed and an example considering only two of the vehicle subsystems is formulated and solved.

40 CFR 69.51 - Motor vehicle diesel fuel.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Motor vehicle diesel fuel. 69.51... (CONTINUED) SPECIAL EXEMPTIONS FROM REQUIREMENTS OF THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel.... (b) Diesel fuel that is designated for use only in Alaska and is used only in Alaska, is exempt from...

40 CFR 69.51 - Motor vehicle diesel fuel.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Motor vehicle diesel fuel. 69.51... (CONTINUED) SPECIAL EXEMPTIONS FROM REQUIREMENTS OF THE CLEAN AIR ACT Alaska § 69.51 Motor vehicle diesel.... (b) Diesel fuel that is designated for use only in Alaska and is used only in Alaska, is exempt from...

California; Antelope Valley Air Quality Management District; VOCs from Motor Vehicle Assembly Coating Operations

EPA Pesticide Factsheets

EPA is proposing to approve a revision to the Antelope Valley Air Quality Management District portion of the California SIP concerning emissions of volatile organic compounds (VOCs) from motor vehicle assembly coating operations.

36 CFR 212.57 - Monitoring of effects of motor vehicle use on designated roads and trails and in designated areas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... motor vehicle use on designated roads and trails and in designated areas. 212.57 Section 212.57 Parks... Roads, Trails, and Areas for Motor Vehicle Use § 212.57 Monitoring of effects of motor vehicle use on designated roads and trails and in designated areas. For each administrative unit of the National Forest...

Modified Universal Design Survey: Enhancing Operability of Launch Vehicle Ground Crew Worksites

NASA Technical Reports Server (NTRS)

Blume, Jennifer L.

2010-01-01

Operability is a driving requirement for next generation space launch vehicles. Launch site ground operations include numerous operator tasks to prepare the vehicle for launch or to perform preflight maintenance. Ensuring that components requiring operator interaction at the launch site are designed for optimal human use is a high priority for operability. To promote operability, a Design Quality Evaluation Survey based on Universal Design framework was developed to support Human Factors Engineering (HFE) evaluation for NASA s launch vehicles. Universal Design per se is not a priority for launch vehicle processing however; applying principles of Universal Design will increase the probability of an error free and efficient design which promotes operability. The Design Quality Evaluation Survey incorporates and tailors the seven Universal Design Principles and adds new measures for Safety and Efficiency. Adapting an approach proven to measure Universal Design Performance in Product, each principle is associated with multiple performance measures which are rated with the degree to which the statement is true. The Design Quality Evaluation Survey was employed for several launch vehicle ground processing worksite analyses. The tool was found to be most useful for comparative judgments as opposed to an assessment of a single design option. It provided a useful piece of additional data when assessing possible operator interfaces or worksites for operability.

Design of a recovery system for a reentry vehicle

NASA Technical Reports Server (NTRS)

Von Eckroth, Wulf; Garrard, William L.; Miller, Norman

1993-01-01

Engineers are often required to design decelerator systems which are deployed in cross-wind orientations. If the system is not designed to minimize 'line sail', damage to the parachutes could result. A Reentry Vehicle Analysis Code (RVAC) and an accompanying graphics animation software program (DISPLAY) are presented in this paper. These computer codes allow the user to quickly apply the Purvis line sail modeling technique to any vehicle and then observe the relative motion of the vehicle, nose cap, suspension lines, pilot and drogue bags and canopies on a computer screen. Data files are created which allow plots of velocities, spacial positions, and dynamic pressures versus time to be generated. The code is an important tool for the design engineer because it integrates two degrees of freedom (DOF) line sail equations with a three DOF model of the reentry body and jettisoned nose cap to provide an animated output.

A review of design issues specific to hypersonic flight vehicles

NASA Astrophysics Data System (ADS)

Sziroczak, D.; Smith, H.

2016-07-01

This paper provides an overview of the current technical issues and challenges associated with the design of hypersonic vehicles. Two distinct classes of vehicles are reviewed; Hypersonic Transports and Space Launchers, their common features and differences are examined. After a brief historical overview, the paper takes a multi-disciplinary approach to these vehicles, discusses various design aspects, and technical challenges. Operational issues are explored, including mission profiles, current and predicted markets, in addition to environmental effects and human factors. Technological issues are also reviewed, focusing on the three major challenge areas associated with these vehicles: aerothermodynamics, propulsion, and structures. In addition, matters of reliability and maintainability are also presented. The paper also reviews the certification and flight testing of these vehicles from a global perspective. Finally the current stakeholders in the field of hypersonic flight are presented, summarizing the active programs and promising concepts.

Impact of methanol vehicles on ozone air quality

NASA Astrophysics Data System (ADS)

Chang, T. Y.; Rudy, S. J.; Kuntasal, G.; Gorse, R. A.

A single-cell trajectory model with an updated chemical mechanism has been used to evaluate the impact on ozone air quality of methanol fueled vehicle (MFV) substitution for conventional fueled vehicles (CFV) in 20 urban areas in the U.S. Recent measurement data for non-methane organic compound (NMOC) concentrations and NMOC/NO x ratios for each of the areas was used. The sensitivity of peak 1-h O 3 values to variations in many of the input parameters has been tested. The functional dependence of peak 1-h O 3 on NMOC/NO x, ratios shows that, for many cities, the maximum O 3 levels occur near the median urban-center 6-9 a.m. NMOC/NO x ratios. The results of the photochemical model computations, including several methanol-fuel substitution scenarios, have been used to derive relative reactivities of methanol and formaldehyde. Per-vehicle O 3 reduction potentials for MFV have also been derived. The reduction potentials and calculated percentage O 3 reductions for selected MFV market-penetrations have been used to estimate the impact of any MFV market-penetration or change in MFV emission factors. All substitution scenarios evaluated lead to projections of lower peak 1-h O 3 levels. Even with significant replacement of CFV by MFV, the reduction of urban O 3 levels appears to be modest. However, the reductions may be significant in comparison to other available O 3-reduction options.

Aerospace Vehicle Design, Spacecraft Section. Volume 1: Project Groups 3-5

NASA Technical Reports Server (NTRS)

1989-01-01

Three groups of student engineers in an aerospace vehicle design course present their designs for a vehicle that can be used to resupply the Space Station Freedom and provide an emergency crew return to earth capability. The vehicle's requirements include a lifetime that exceeds six years, low cost, the capability for withstanding pressurization, launch, orbit, and reentry hazards, and reliability. The vehicle's subsystems are analyzed. These subsystems are structures, communication and command data systems, attitude and articulation control, life support and crew systems, power and propulsion, reentry and recovery systems, and mission management, planning, and costing.

High-resolution simulation of link-level vehicle emissions and concentrations for air pollutants in a traffic-populated eastern Asian city

NASA Astrophysics Data System (ADS)

Zhang, Shaojun; Wu, Ye; Huang, Ruikun; Wang, Jiandong; Yan, Han; Zheng, Yali; Hao, Jiming

2016-08-01

Vehicle emissions containing air pollutants created substantial environmental impacts on air quality for many traffic-populated cities in eastern Asia. A high-resolution emission inventory is a useful tool compared with traditional tools (e.g. registration data-based approach) to accurately evaluate real-world traffic dynamics and their environmental burden. In this study, Macau, one of the most populated cities in the world, is selected to demonstrate a high-resolution simulation of vehicular emissions and their contribution to air pollutant concentrations by coupling multimodels. First, traffic volumes by vehicle category on 47 typical roads were investigated during weekdays in 2010 and further applied in a networking demand simulation with the TransCAD model to establish hourly profiles of link-level vehicle counts. Local vehicle driving speed and vehicle age distribution data were also collected in Macau. Second, based on a localized vehicle emission model (e.g. the emission factor model for the Beijing vehicle fleet - Macau, EMBEV-Macau), this study established a link-based vehicle emission inventory in Macau with high resolution meshed in a temporal and spatial framework. Furthermore, we employed the AERMOD (AMS/EPA Regulatory Model) model to map concentrations of CO and primary PM2.5 contributed by local vehicle emissions during weekdays in November 2010. This study has discerned the strong impact of traffic flow dynamics on the temporal and spatial patterns of vehicle emissions, such as a geographic discrepancy of spatial allocation up to 26 % between THC and PM2.5 emissions owing to spatially heterogeneous vehicle-use intensity between motorcycles and diesel fleets. We also identified that the estimated CO2 emissions from gasoline vehicles agreed well with the statistical fuel consumption in Macau. Therefore, this paper provides a case study and a solid framework for developing high-resolution environment assessment tools for other vehicle-populated cities

Comparison of Two Multidisciplinary Optimization Strategies for Launch-Vehicle Design

NASA Technical Reports Server (NTRS)

Braun, R. D.; Powell, R. W.; Lepsch, R. A.; Stanley, D. O.; Kroo, I. M.

1995-01-01

The investigation focuses on development of a rapid multidisciplinary analysis and optimization capability for launch-vehicle design. Two multidisciplinary optimization strategies in which the analyses are integrated in different manners are implemented and evaluated for solution of a single-stage-to-orbit launch-vehicle design problem. Weights and sizing, propulsion, and trajectory issues are directly addressed in each optimization process. Additionally, the need to maintain a consistent vehicle model across the disciplines is discussed. Both solution strategies were shown to obtain similar solutions from two different starting points. These solutions suggests that a dual-fuel, single-stage-to-orbit vehicle with a dry weight of approximately 1.927 x 10(exp 5)lb, gross liftoff weight of 2.165 x 10(exp 6)lb, and length of 181 ft is attainable. A comparison of the two approaches demonstrates that treatment or disciplinary coupling has a direct effect on optimization convergence and the required computational effort. In comparison with the first solution strategy, which is of the general form typically used within the launch vehicle design community at present, the second optimization approach is shown to he 3-4 times more computationally efficient.

Inter-Module Ventilation Changes to the International Space Station Vehicle to Support Integration of the International Docking Adapter and Commercial Crew Vehicles

NASA Technical Reports Server (NTRS)

Link, Dwight E., Jr.; Balistreri, Steven F., Jr.

2015-01-01

The International Space Station (ISS) Environmental Control and Life Support System (ECLSS) is continuing to evolve in the post-Space Shuttle era. The ISS vehicle configuration that is in operation was designed for docking of a Space Shuttle vehicle, and designs currently under development for commercial crew vehicles require different interfaces. The ECLSS Temperature and Humidity Control Subsystem (THC) Inter-Module Ventilation (IMV) must be modified in order to support two docking interfaces at the forward end of ISS, to provide the required air exchange. Development of a new higher-speed IMV fan and extensive ducting modifications are underway to support the new Commercial Crew Vehicle interfaces. This paper will review the new ECLSS IMV development requirements, component design and hardware status, subsystem analysis and testing performed to date, and implementation plan to support Commercial Crew Vehicle docking.

Development of Integrated Programs for Aerospace-vehicle design (IPAD): Reference design process

NASA Technical Reports Server (NTRS)

Meyer, D. D.

1979-01-01

The airplane design process and its interfaces with manufacturing and customer operations are documented to be used as criteria for the development of integrated programs for the analysis, design, and testing of aerospace vehicles. Topics cover: design process management, general purpose support requirements, design networks, and technical program elements. Design activity sequences are given for both supersonic and subsonic commercial transports, naval hydrofoils, and military aircraft.

Large school bus design vehicle dimensions

DOT National Transportation Integrated Search

1998-09-01

A survey of United States school bus operators and manufacturers was conducted to define the larger sizes of school buses in regular use. A mid-60 passenger type-c bus (SB-C) and a mid-80 passenger type-D bus (SB-D) were selected as design vehicles. ...

Conceptual design for aerospace vehicles

NASA Technical Reports Server (NTRS)

Gratzer, Louis B.

1989-01-01

The designers of aircraft and more recently, aerospace vehicles have always struggled with the problems of evolving their designs to produce a machine which would perform its assigned task(s) in some optimum fashion. Almost invariably this involved dealing with more variables and constraints than could be handled in any computationally feasible way. With the advent of the electronic digital computer, the possibilities for introducing more variable and constraints into the initial design process led to greater expectations for improvement in vehicle (system) efficiency. The creation of the large scale systems necessary to achieve optimum designs has, for many reason, proved to be difficult. From a technical standpoint, significant problems arise in the development of satisfactory algorithms for processing of data from the various technical disciplines in a way that would be compatible with the complex optimization function. Also, the creation of effective optimization routines for multi-variable and constraint situations which could lead to consistent results has lagged. The current capability for carrying out the conceptual design of an aircraft on an interdisciplinary bases was evaluated to determine the need for extending this capability, and if necessary, to recommend means by which this could be carried out. Based on a review of available documentation and individual consultations, it appears that there is extensive interest at Langley Research Center as well as in the aerospace community in providing a higher level of capability that meets the technical challenges. By implication, the current design capability is inadequate and it does not operate in a way that allows the various technical disciplines to participate and cooperately interact in the design process. Based on this assessment, it was concluded that substantial effort should be devoted to developing a computer-based conceptual design system that would provide the capability needed for the near

Hyper-X Vehicle Model - Top Rear View

NASA Technical Reports Server (NTRS)

1996-01-01

This aft-quarter model view of NASA's X-43A 'Hyper-X' or Hypersonic Experimental Vehicle shows its sleek, geometric design. The X-43A was developed to flight test a dual-mode ramjet/scramjet propulsion system at speeds from Mach 7 up to Mach 10 (7 to 10 times the speed of sound, which varies with temperature and altitude). Hyper-X, the flight vehicle for which is designated as X-43A, is an experimental flight-research program seeking to demonstrate airframe-integrated, 'air-breathing' engine technologies that promise to increase payload capacity for future vehicles, including hypersonic aircraft (faster than Mach 5) and reusable space launchers. This multiyear program is currently underway at NASA Dryden Flight Research Center, Edwards, California. The Hyper-X schedule calls for its first flight later this year (2000). Hyper-X is a joint program, with Dryden sharing responsibility with NASA's Langley Research Center, Hampton, Virginia. Dryden's primary role is to fly three unpiloted X-43A research vehicles to validate engine technologies and hypersonic design tools as well as the hypersonic test facility at Langley. Langley manages the program and leads the technology development effort. The Hyper-X Program seeks to significantly expand the speed boundaries of air-breathing propulsion by being the first aircraft to demonstrate an airframe-integrated, scramjet-powered free flight. Scramjets (supersonic-combustion ramjets) are ramjet engines in which the airflow through the whole engine remains supersonic. Scramjet technology is challenging because only limited testing can be performed in ground facilities. Long duration, full-scale testing requires flight research. Scramjet engines are air-breathing, capturing their oxygen from the atmosphere. Current spacecraft, such as the Space Shuttle, are rocket powered, so they must carry both fuel and oxygen for propulsion. Scramjet technology-based vehicles need to carry only fuel. By eliminating the need to carry oxygen

Design for Safety - The Ares Launch Vehicles Paradigm Change

NASA Technical Reports Server (NTRS)

Safie, Fayssal M.; Maggio, Gaspare

2010-01-01

The lessons learned from the S&MA early involvement in the Ares I launch vehicle design phases proved that performing an in-line function jointly with engineering is critical for S&MA to have an effective role in supporting the system, element, and component design. These lessons learned were used to effectively support the Ares V conceptual design phase and planning for post conceptual design phases. The Top level Conceptual LOM assessment for Ares V performed by the S&MA community jointly with the engineering Advanced Concept Office (ACO) was influential in the final selection of the Ares V system configuration. Post conceptual phase, extensive reliability effort should be planned to support future Heavy Lift Launch Vehicles (HLLV) design. In-depth reliability analysis involving the design, manufacturing, and system engineering communities is critical to understand design and process uncertainties and system integrated failures.

Advanced vehicle concepts systems and design analysis studies

NASA Technical Reports Server (NTRS)

Waters, Mark H.; Huynh, Loc C.

1994-01-01

The work conducted by the ELORET Institute under this Cooperative Agreement includes the modeling of hypersonic propulsion systems and the evaluation of hypersonic vehicles in general and most recently hypersonic waverider vehicles. This work in hypersonics was applied to the design of a two-stage to orbit launch vehicle which was included in the NASA Access to Space Project. Additional research regarded the Oblique All-Wing (OAW) Project at NASA ARC and included detailed configuration studies of OAW transport aircraft. Finally, work on the modeling of subsonic and supersonic turbofan engines was conducted under this research program.

Rotorcraft control system design for uncertain vehicle dynamics using quantitative feedback theory

NASA Technical Reports Server (NTRS)

Hess, R. A.

1994-01-01

Quantitative Feedback Theory describes a frequency-domain technique for the design of multi-input, multi-output control systems which must meet time or frequency domain performance criteria when specified uncertainty exists in the linear description of the vehicle dynamics. This theory is applied to the design of the longitudinal flight control system for a linear model of the BO-105C rotorcraft. Uncertainty in the vehicle model is due to the variation in the vehicle dynamics over a range of airspeeds from 0-100 kts. For purposes of exposition, the vehicle description contains no rotor or actuator dynamics. The design example indicates the manner in which significant uncertainty exists in the vehicle model. The advantage of using a sequential loop closure technique to reduce the cost of feedback is demonstrated by example.

Design of an unmanned, reusable vehicle to de-orbit debris in Earth orbit

NASA Technical Reports Server (NTRS)

Aziz, Shahed; Cunningham, Timothy W.; Moore-Mccassey, Michelle

1990-01-01

The space debris problem is becoming more important because as orbital missions increase, the amount of debris increases. It was the design team's objective to present alternative designs and a problem solution for a deorbiting vehicle that will alleviate the problem by reducing the amount of large debris in earth orbit. The design team was asked to design a reusable, unmanned vehicle to de-orbit debris in earth orbit. The design team will also construct a model to demonstrate the system configuration and key operating features. The alternative designs for the unmanned, reusable vehicle were developed in three stages: selection of project requirements and success criteria, formulation of a specification list, and the creation of alternatives that would satisfy the standards set forth by the design team and their sponsor. The design team selected a Chain and Bar Shot method for deorbiting debris in earth orbit. The De-orbiting Vehicle (DOV) uses the NASA Orbital Maneuvering Vehicle (OMV) as the propulsion and command modules with the deorbiting module attached to the front.

High Work, High-Efficiency Turbines for Uninhabited Aerial Vehicles (UAVs)

DTIC Science & Technology

2013-09-01

controlling highly loaded LP turbine blades have been demonstrated in a low speed linear cascade at the AFRL Low Speed Wind Tunnel (LSWT) facility that...34, pp. 1570-1577. [34] Selig M. S. and Mcgranahan, B. D., “ Wind Tunnel Aerodynamic Tests of Six Airfoils for Use on Small Wind Turbines .” National...aerodynamic flows is of interest in many design domains such as air vehicles, turbomachinery, and wind turbines . Micro-air-vehicles (MAV) which have small

Aerodynamics of a bio-inspired flexible flapping-wing micro air vehicle.

PubMed

Nakata, T; Liu, H; Tanaka, Y; Nishihashi, N; Wang, X; Sato, A

2011-12-01

MAVs (micro air vehicles) with a maximal dimension of 15 cm and nominal flight speeds of around 10 m s⁻¹, operate in a Reynolds number regime of 10⁵ or lower, in which most natural flyers including insects, bats and birds fly. Furthermore, due to their light weight and low flight speed, the MAVs' flight characteristics are substantially affected by environmental factors such as wind gust. Like natural flyers, the wing structures of MAVs are often flexible and tend to deform during flight. Consequently, the aero/fluid and structural dynamics of these flyers are closely linked to each other, making the entire flight vehicle difficult to analyze. We have recently developed a hummingbird-inspired, flapping flexible wing MAV with a weight of 2.4-3.0 g and a wingspan of 10-12 cm. In this study, we carry out an integrated study of the flexible wing aerodynamics of this flapping MAV by combining an in-house computational fluid dynamic (CFD) method and wind tunnel experiments. A CFD model that has a realistic wing planform and can mimic realistic flexible wing kinematics is established, which provides a quantitative prediction of unsteady aerodynamics of the four-winged MAV in terms of vortex and wake structures and their relationship with aerodynamic force generation. Wind tunnel experiments further confirm the effectiveness of the clap and fling mechanism employed in this bio-inspired MAV as well as the importance of the wing flexibility in designing small flapping-wing MAVs.

Systems Analysis and Structural Design of an Unpressurized Cargo Delivery Vehicle

NASA Technical Reports Server (NTRS)

Wu, K. Chauncey; Cruz, Jonathan N.; Antol, Jeffrey; Sasamoto, Washito A.

2007-01-01

The International Space Station will require a continuous supply of replacement parts for ongoing maintenance and repair after the planned retirement of the Space Shuttle in 2010. These parts are existing line-replaceable items collectively called Orbital Replacement Units, and include heavy and oversized items such as Control Moment Gyroscopes and stowed radiator arrays originally intended for delivery aboard the Space Shuttle. Current resupply spacecraft have limited to no capability to deliver these external logistics. In support of NASA's Exploration Systems Architecture Study, a team at Langley Research Center designed an Unpressurized Cargo Delivery Vehicle to deliver bulk cargo to the Space Station. The Unpressurized Cargo Delivery Vehicle was required to deliver at least 13,200 lbs of cargo mounted on at least 18 Flight Releasable Attachment Mechanisms. The Crew Launch Vehicle design recommended in the Exploration Systems Architecture Study would be used to launch one annual resupply flight to the International Space Station. The baseline vehicle design developed here has a cargo capacity of 16,000 lbs mounted on up to 20 Flight Releasable Attachment Mechanisms. Major vehicle components are a 5.5m-diameter cargo module containing two detachable cargo pallets with the payload, a Service Module to provide propulsion and power, and an aerodynamic nose cone. To reduce cost and risk, the Service Module is identical to the one used for the Crew Exploration Vehicle design.

Selecting Design Parameters for Flying Vehicles

NASA Astrophysics Data System (ADS)

Makeev, V. I.; Strel'nikova, E. A.; Trofimenko, P. E.; Bondar', A. V.

2013-09-01

Studying the influence of a number of design parameters of solid-propellant rockets on the longitudinal and lateral dispersion is an important applied problem. A mathematical model of a rigid body of variable mass moving in a disturbed medium exerting both wave drag and friction is considered. The model makes it possible to determine the coefficients of aerodynamic forces and moments, which affect the motion of vehicles, and to assess the effect of design parameters on their accuracy

Winged cargo return vehicle conceptual design

NASA Technical Reports Server (NTRS)

1990-01-01

NASA is committed to placing a permanent space station in Earth orbit in the 1990's. Space Station Freedom (SSF) will be located in a 220 n.m. orbit at 28.5 degrees inclination. The Winged Cargo Return Vehicle's (CRV) primary mission is to support SSF crew by flying regular resupply missions. The winged CRV is designed to be reusable, dry land recoverable, and unmanned. The CRV will be launched inline on three liquid hydrogen/oxygen rocket boosters with a payload capacity of 113,000 lbs. The three boosters will take the CRV to an orbit of 50 by 110 n.m. From this altitude the orbital manuevering engine will place the vehicle in synchronous orbit with the space station. The winged CRV will deliver cargo modules to the space station by direct docking or by remaining outside the SSF command zone and using the Orbital Maneuvering Vehicle (OMV) to transfer cargo. After unloading/loading, the CRV will deorbit and fly back to Kennedy Space Center. The CRV has a wing span of 57.8 feet, a length of 76.0 feet, and a dry weight of 61.5 klb. The cargo capacity of the vehicle is 44.4 klb. The vehicle has a lift-drag ratio of 1.28 (hypersonic) and 6.0 (subsonic), resulting in a 1351 n.m. cross range. The overall mission length ranges between 18.8 and 80.5 hr. The operational period will be the years 2000 to 2020.

Towards Comprehensive Variation Models for Designing Vehicle Monitoring Systems

NASA Technical Reports Server (NTRS)

McAdams, Daniel A.; Tumer, Irem Y.; Clancy, Daniel (Technical Monitor)

2002-01-01

When designing vehicle vibration monitoring systems for aerospace devices, it is common to use well-established models of vibration features to determine whether failures or defects exist. Most of the algorithms used for failure detection rely on these models to detect significant changes in a flight environment. In actual practice, however, most vehicle vibration monitoring systems are corrupted by high rates of false alarms and missed detections. This crucial roadblock makes their implementation in real vehicles (e.g., helicopter transmissions and aircraft engines) difficult, making their operation costly and unreliable. Research conducted at the NASA Ames Research Center has determined that a major reason for the high rates of false alarms and missed detections is the numerous sources of statistical variations that are not taken into account in the modeling assumptions. In this paper, we address one such source of variations, namely, those caused during the design and manufacturing of rotating machinery components that make up aerospace systems. We present a novel way of modeling the vibration response by including design variations via probabilistic methods. Using such models, we develop a methodology to account for design and manufacturing variations, and explore the changes in the vibration response to determine its stochastic nature. We explore the potential of the methodology using a nonlinear cam-follower model, where the spring stiffness values are assumed to follow a normal distribution. The results demonstrate initial feasibility of the method, showing great promise in developing a general methodology for designing more accurate aerospace vehicle monitoring systems.

Unmanned air vehicle (UAV) ultra-persitence research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dron, S. B.

2012-03-01

considered. Fundamental cost driver analysis was also performed. System development plans were drafted in order to determine where the technological and programmatic critical paths lay. As a result of this effort, UAVs were to be able to provide far more surveillance time and intelligence information per mission while reducing the high cost of support activities. This technology was intended to create unmatched global capabilities to observe and preempt terrorist and weapon of mass destruction (WMD) activities. Various DOE laboratory and contractor personnel and facilities could have been used to perform detailed engineering, fabrication, assembly and test operations including follow-on operational support. Unfortunately, none of the results will be used in the near-term or mid-term future. NGIS UMS and SNL felt that the technical goals for the project were accomplished. NGIS UMS was quite pleased with the results of analysis and design although it was disappointing to all that the political realities would not allow use of the results. Technology and system designs evaluated under this CRADA had previously never been applied to unmanned air vehicles (UAVs). Based upon logistic support cost predictions, because the UAVs would not have had to refuel as often, forward basing support costs could have been reduced due to a decrease in the number and extent of support systems and personnel being required to operate UAVs in remote areas. Basic application of the advanced propulsion and power approach is well understood and industry now understands the technical, safety, and political issues surrounding implementation of these strategies. However, the overall economic impact was not investigated. The results will not be applied/implemented. No near-term benefit to industry or the taxpayer will be encountered as a result of these studies.« less

Development and Design of Zero-g Liquid Quantity Gauge for Solar Thermal Vehicle

NASA Technical Reports Server (NTRS)

Dodge, Franklin T.; Green, Steven T.; Petullo, Steven P.; VanDresar, Neil T.

2002-01-01

The development and design of a cryogenic liquid quantity gauge for zero-gravity (zero-g) applications are described. The gauge, named the compression mass gauge (CMG), operates on the principle of slightly changing the volume of the tank by an oscillating bellows. The resulting pressure change is measured and used to predict the volume of vapor in the tank, from which the volume of liquid is computed. For each gauging instance, pressures are measured for several different bellows frequencies to enable minor real-gas effects to be quantified and thereby to obtain a gauging accuracy of 11 percent of tank volume. The CMG has been selected by NASA's Future-X program for a flight demonstration on the United States Air Force-Boeing Solar Orbit Transfer Vehicle Space Experiment (SOTVSE). This report reviews the design trade studies needed for the CMG to satisfy the SOTVSE limitations on its power, volume, and mass and also describes the mechanical design of the CMG.

The Role of Guidance, Navigation, and Control in Hypersonic Vehicle Multidisciplinary Design and Optimization

NASA Technical Reports Server (NTRS)

Ouzts, Peter J.; Soloway, Donald I.; Moerder, Daniel D.; Wolpert, David H.; Benavides, Jose Victor

2009-01-01

Airbreathing hypersonic systems offer distinct performance advantages over rocket-based systems for space access vehicles. However, these performance advantages are dependent upon advances in current state-of-the-art technologies in many areas such as ram/scramjet propulsion integration, high temperature materials, aero-elastic structures, thermal protection systems, transition to hypersonics and hypersonic control elements within the framework of complex physics and new design methods. The complex interactions between elements of an airbreathing hypersonic vehicle represent a new paradigm in vehicle design to achieve the optimal performance necessary to meet space access mission objectives. In the past, guidance, navigation, and control (GNC) analysis often follows completion of the vehicle conceptual design process. Individual component groups design subsystems which are then integrated into a vehicle configuration. GNC is presented the task of developing control approaches to meet vehicle performance objectives given that configuration. This approach may be sufficient for vehicles where significant performance margins exist. However, for higher performance vehicles engaging the GNC discipline too late in the design cycle has been costly. For example, the X-29 experimental flight vehicle was built as a technology demonstrator. One of the many technologies to be demonstrated was the use of light-weight material composites for structural components. The use of light-weight materials increased the flexibility of the X- 29 beyond that of conventional metal alloy constructed aircraft. This effect was not considered when the vehicle control system was designed and built. The impact of this is that the control system did not have enough control authority to compensate for the effects of the first fundamental structural mode of the vehicle. As a result, the resulting pitch rate response of the vehicle was below specification and no post-design changes could recover the

Air Force Reusable Booster System A Quick-look, Design Focused Modeling and Cost Analysis Study

NASA Technical Reports Server (NTRS)

Zapata, Edgar

2011-01-01

Presents work supporting the Air force Reusable Booster System (RBS) - A Cost Study with Goals as follows: Support US launch systems decision makers, esp. in regards to the research, technology and demonstration investments required for reusable systems to succeed. Encourage operable directions in Reusable Booster / Launch Vehicle Systems technology choices, system design and product and process developments. Perform a quick-look cost study, while developing a cost model for more refined future analysis.

Numerical Investigation of Aerodynamic Braking for a Ground Vehicle

NASA Astrophysics Data System (ADS)

Devanuri, Jaya Krishna

2018-06-01

The purpose of this article is to observe the effect of an air brake on the aerodynamics of a ground vehicle and also to study the influence of change in the parameters like the velocity of the vehicle, the angle of inclination, height, and position of the air brake on the aerodynamics of the vehicle body. The test subject used is an Ahmed body which is a generic 3D car body as it retains all the aerodynamic characteristics of a ground vehicle. Numerical investigation has been carried out by RNG k-ɛ turbulence model. Results are presented in terms of streamlines and drag coefficient to understand the influence of pertinent parameters on flow physics. It is found that with the use of an air brake, though the drag coefficient remains more or less constant with velocity, it increases with the increase in height and angle of inclination of the air brake. But the effect of position of air brake on the coefficient of drag is surprising since for certain heights of the air brake the drag coefficient is maximum at the foremost point and as the air brake moves towards the rear it is first observed to decrease and then increase. It is also observed that with the increase in height of the air brake the drag coefficient monotonically decreases as the position of the air brake is moved towards the rear. Taguchi method has been employed with L16 orthogonal array to obtain the optimal configuration for the air brake. For each of the selected parameters, four different levels have been chosen to obtain the maximum drag coefficient value. The study could provide an invaluable database for the optimal design of an airbrake for a ground vehicle.

Design Considerations of ISTAR Hydrocarbon Fueled Combustor Operating in Air Augmented Rocket, Ramjet and Scramjet Modes

NASA Technical Reports Server (NTRS)

Andreadis, Dean; Drake, Alan; Garrett, Joseph L.; Gettinger, Christopher D.; Hoxie, Stephen S.

2003-01-01

The development and ground test of a rocket-based combined cycle (RBCC) propulsion system is being conducted as part of the NASA Marshall Space Flight Center (MSFC) Integrated System Test of an Airbreathing Rocket (ISTAR) program. The eventual flight vehicle (X-43B) is designed to support an air-launched self-powered Mach 0.7 to 7.0 demonstration of an RBCC engine through all of its airbreathing propulsion modes - air augmented rocket (AAR), ramjet (RJ), and scramjet (SJ). Through the use of analytical tools, numerical simulations, and experimental tests the ISTAR program is developing and validating a hydrocarbon-fueled RBCC combustor design methodology. This methodology will then be used to design an integrated RBCC propulsion system that produces robust ignition and combustion stability characteristics while maximizing combustion efficiency and minimizing drag losses. First order analytical and numerical methods used to design hydrocarbon-fueled combustors are discussed with emphasis on the methods and determination of requirements necessary to establish engine operability and performance characteristics.

Design Considerations of Istar Hydrocarbon Fueled Combustor Operating in Air Augmented Rocket, Ramjet and Scramjet Modes

NASA Technical Reports Server (NTRS)

Andreadis, Dean; Drake, Alan; Garrett, Joseph L.; Gettinger, Christopher D.; Hoxie, Stephen S.

2002-01-01

The development and ground test of a rocket-based combined cycle (RBCC) propulsion system is being conducted as part of the NASA Marshall Space Flight Center (MSFC) Integrated System Test of an Airbreathing Rocket (ISTAR) program. The eventual flight vehicle (X-43B) is designed to support an air-launched self-powered Mach 0.7 to 7.0 demonstration of an RBCC engine through all of its airbreathing propulsion modes - air augmented rocket (AAR), ramjet (RJ), and scramjet (SJ). Through the use of analytical tools, numerical simulations, and experimental tests the ISTAR program is developing and validating a hydrocarbon-fueled RBCC combustor design methodology. This methodology will then be used to design an integrated RBCC propulsion system thai: produces robust ignition and combustion stability characteristics while maximizing combustion efficiency and minimizing drag losses. First order analytical and numerical methods used to design hydrocarbon-fueled combustors are discussed with emphasis on the methods and determination of requirements necessary to establish engine operability and performance characteristics.

Flexible Wing Base Micro Aerial Vehicles: Micro Air Vehicles (MAVs) for Surveillance and Remote Sensor Delivery

NASA Technical Reports Server (NTRS)

Ifju, Peter

2002-01-01

Micro Air Vehicles (MAVs) will be developed for tracking individuals, locating terrorist threats, and delivering remote sensors, for surveillance and chemical/biological agent detection. The tasks are: (1) Develop robust MAV platform capable of carrying sensor payload. (2) Develop fully autonomous capabilities for delivery of sensors to remote and distant locations. The current capabilities and accomplishments are: (1) Operational electric (inaudible) 6-inch MAVs with novel flexible wing, providing superior aerodynamic efficiency and control. (2) Vision-based flight stability and control (from on-board cameras).

Medium Altitude Endurance Unmanned Air Vehicle

NASA Astrophysics Data System (ADS)

Ernst, Larry L.

1994-10-01

The medium altitude endurance unmanned air vehicle (MAE UAV) program (formerly the tactical endurance TE UAV) is a new effort initiated by the Department of Defense to develop a ground launched UAV that can fly out 500 miles, remain on station for 24 hours, and return. It will transmit high resolution optical, infrared, and synthetic aperture radar (SAR) images of well-defended target areas through satellite links. It will provide near-real-time, releasable, low cost/low risk surveillance, targeting and damage assessment complementary to that of satellites and manned aircraft. The paper describes specific objectives of the MAE UAV program (deliverables and schedule) and the program's unique position as one of several programs to streamline the acquisition process under the cognizance of the newly established Airborne Reconnaissance Office. I discuss the system requirements and operational concept and describe the technical capabilities and characteristics of the major subsystems (airframe, propulsion, navigation, sensors, communication links, ground station, etc.) in some detail.

Design of Modular, Shape-transitioning Inlets for a Conical Hypersonic Vehicle

NASA Technical Reports Server (NTRS)

Gollan, Rowan J.; Smart, Michael K.

2010-01-01

For a hypersonic vehicle, propelled by scramjet engines, integration of the engines and airframe is highly desirable. Thus, the forward capture shape of the engine inlet should conform to the vehicle body shape. Furthermore, the use of modular engines places a constraint on the shape of the inlet sidewalls. Finally, one may desire a combustor cross- section shape that is different from that of the inlet. These shape constraints for the inlet can be accommodated by employing a streamline-tracing and lofting technique. This design technique was developed by Smart for inlets with a rectangular-to-elliptical shape transition. In this paper, we generalise that technique to produce inlets that conform to arbitrary shape requirements. As an example, we show the design of a body-integrated hypersonic inlet on a winged-cone vehicle, typical of what might be used in a three-stage orbital launch system. The special challenge of inlet design for this conical vehicle at an angle-of-attack is also discussed. That challenge is that the bow shock sits relatively close to the vehicle body.

Reductions in deaths in frontal crashes among right front passengers in vehicles equipped with passenger air bags.

PubMed

Braver, E R; Ferguson, S A; Greene, M A; Lund, A K

1997-11-05

Virtually all new cars now are equipped with passenger air bags. Determining whether passenger air bags are saving lives is important, particularly because passenger air bags have caused some deaths among children and adults. To assess the effectiveness of passenger air bags in reducing the risk of death in frontal crashes for right front passengers. Air bags are designed to protect occupants in frontal crashes. Using Fatality Analysis Reporting System data for calendar years 1992 through 1995, the relative frequency of right front passenger deaths in frontal vs nonfrontal fatal crashes was compared for cars with dual air bags and for cars with driver-only air bags. Odds of right front passengers dying in frontal compared with nonfrontal fatal crashes were computed for 1992 through 1995 model year cars with dual air bags and for cars with driver-only air bags. Percentage reductions in right front passenger deaths in dual air bag vehicles were estimated. Right front passenger fatalities were 18% lower than expected in frontal crashes of cars with dual air bags and 11% lower in all crashes. An estimated 73 fewer than expected right front passengers died in 1992 through 1995 model cars with dual air bags during 1992 through 1995. The risk of frontal crash death for right front passengers in cars with dual air bags was reduced 14% among those reported to be using belts and 23% among belt nonusers. Children younger than 10 years in cars with dual air bags had a 34% increased risk of dying in frontal crashes. Passenger air bags were associated with substantial reductions in fatalities among right front passengers in frontal crashes. However, more children are being killed than are being saved by air bags. Immediate countermeasures to reduce the dangers of air bags to children and adults are suggested.

Aspergillus prevalence in air conditioning filters from vehicles: taxis for patient transportation, forklifts, and personal vehicles.

PubMed

Viegas, Carla; Moreira, Ricardo; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Gomes, Anita Quintal; Viegas, Susana

2018-05-04

The frequency and importance of Aspergillus infections is increasing worldwide. This study aimed to assess the occupational exposure of forklifts and taxi drivers to Aspergillus spp. Nineteen filters from air conditioning system of taxis, 17 from forklifts and 37 from personal vehicles were assessed. Filters extract were streaked onto MEA, DG18 and in azole-supplemented media. Real-time quantitative PCR amplification of selected Aspergillus species-complex was also performed. Forklifts filter samples presented higher median values. Aspergillus section Nigri was the most observed in forklifts filters in MEA (28.2%) and in azole-supplemented media. DNA from Aspergillus sections Fumigati and Versicolores was successfully amplified by qPCR. This study enlightens the added value of using filters from the air conditioning system to assess Aspergillus spp. occupational exposure. Aspergillus azole resistance screening should be included in future occupational exposure assessments.

4D metrology of flapping-wing micro air vehicle based on fringe projection

NASA Astrophysics Data System (ADS)

Zhang, Qican; Huang, Lei; Chin, Yao-Wei; Keong, Lau-Gih; Asundi, Anand

2013-06-01

Inspired by dominant flight of the natural flyers and driven by civilian and military purposes, micro air vehicle (MAV) has been developed so far by passive wing control but still pales in aerodynamic performance. Better understanding of flapping wing flight mechanism is eager to improve MAV's flight performance. In this paper, a simple and effective 4D metrology technique to measure full-field deformation of flapping membrane wing is presented. Based on fringe projection and 3D Fourier analysis, the fast and complex dynamic deformation, including wing rotation and wing stroke, of a flapping wing during its flight can be accurately reconstructed from the deformed fringe patterns recorded by a highspeed camera. An experiment was carried on a flapping-wing MAV with 5-cm span membrane wing beating at 30 Hz, and the results show that this method is effective and will be useful to the aerodynamicist or micro aircraft designer for visualizing high-speed complex wing deformation and consequently aid the design of flapping wing mechanism to enhanced aerodynamic performance.

Design of a Long Endurance Titan VTOL Vehicle

NASA Technical Reports Server (NTRS)