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1

Aerodynamic Design of Road Vehicles  

NASA Technical Reports Server (NTRS)

Guidebook discusses design of road vehicles to reduce aerodynamic drag. Book presents strategy for integrating aerodynamic design into vehicle design. Book written for readers lacking experience in aerodynamics.

Kurtz, D. W.

1985-01-01

2

Building Spacecraft & Launch Vehicles! Space Vehicle Design!  

E-print Network

)" ·! Von Braun group used to developing integrated vehicle and payload; now different design teams would HQ" ·! Lunar crasher" ·! Chance Vought study" ·! Weight-lifting capability of Saturn C-5" ·! Von Braun's acquiescence for LOR" Joe Shea" ·! Evolution of Saturn launch vehicles" ·! Development of rocket

Stengel, Robert F.

3

Hybrid Vehicle Design Challenge  

NSDL National Science Digital Library

Through four lessons and four hands-on associated activities, this unit provides a way to teach the overarching concept of energy as it relates to both kinetic and potential energy. Within these topics, students are exposed to gravitational potential, spring potential, the Carnot engine, temperature scales and simple magnets. During the module, students apply these scientific concepts to solve the following engineering challenge: "The rising price of gasoline has many effects on the US economy and the environment. You have been contracted by an engineering firm to help design a physical energy storage system for a new hybrid vehicle for Nissan. How would you go about solving this problem? What information would you consider to be important to know? You will create a small prototype of your design idea and make a sales pitch to Nissan at the end of the unit." This module is built around the Legacy Cycle, a format that incorporates findings from educational research on how people best learn. This module is written for a first-year algebra-based physics class, though it could easily be modified for conceptual physics.

VU Bioengineering RET Program,

4

Advanced concepts in electric vehicle design  

Microsoft Academic Search

In 1994, the Eco-Vehicle Project was begun to develop an electric vehicle (EV) using a ground-up design approach that incorporates unique designs specific to an EV. The Eco-Vehicle will be a high-performance, but ultrasmall, battery-powered vehicle. New designs for the Eco-Vehicle include an in-wheel motor drive system, a hollow load floor which will house the batteries, and a new battery

Hiroshi Shimizu; Junji Harada; Colby Bland; Kiyomoto Kawakami; Lam Chan

1997-01-01

5

Modeling Languages Refine Vehicle Design  

NASA Technical Reports Server (NTRS)

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.

2009-01-01

6

The Aerospace Vehicle Interactive Design system  

NASA Technical Reports Server (NTRS)

The aerospace vehicle interactive design (AVID) is a computer aided design that was developed for the conceptual and preliminary design of aerospace vehicles. The AVID system evolved from the application of several design approaches in an advanced concepts environment in which both mission requirements and vehicle configurations are continually changing. The basic AVID software facilitates the integration of independent analysis programs into a design system where the programs can be executed individually for analysis or executed in groups for design iterations and parametric studies. Programs integrated into an AVID system for launch vehicle design include geometry, aerodynamics, propulsion, flight performance, mass properties, and economics.

Wilhite, A. W.

1981-01-01

7

The Aerospace Vehicle Interactive Design system  

NASA Technical Reports Server (NTRS)

The Aerospace Vehicle Interactive Design (AVID) is a computer-aided design system that was developed for the conceptual and preliminary design of aerospace vehicles. The AVID system evolved from the application of several design approaches in an advanced concepts environment in which both mission requirements and vehicle configurations are continually changing. The basic AVID software facilitates the integration of independent analysis programs into a design system where the programs can be executed individually for analysis or executed in groups for design iterations and parametric studies. Programs that have been integrated into an AVID system for launch vehicle design include geometry, aerodynamics, propulsion, flight performance, mass properties, and economics.

Wilhite, A. W.

1981-01-01

8

Delta Clipper vehicle design for supportability  

NASA Astrophysics Data System (ADS)

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.

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

1993-02-01

9

Heat source reentry vehicle design study  

NASA Technical Reports Server (NTRS)

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.

Ryan, R. L.

1971-01-01

10

Vehicle systems design optimization study  

NASA Technical Reports Server (NTRS)

The optimum vehicle configuration and component locations are determined for an electric drive vehicle based on using the basic structure of a current production subcompact vehicle. The optimization of an electric vehicle layout requires a weight distribution in the range of 53/47 to 62/38 in order to assure dynamic handling characteristics comparable to current internal combustion engine vehicles. Necessary modification of the base vehicle can be accomplished without major modification of the structure or running gear. As long as batteries are as heavy and require as much space as they currently do, they must be divided into two packages, one at front under the hood and a second at the rear under the cargo area, in order to achieve the desired weight distribution. The weight distribution criteria requires the placement of batteries at the front of the vehicle even when the central tunnel is used for the location of some batteries. The optimum layout has a front motor and front wheel drive. This configuration provides the optimum vehicle dynamic handling characteristics and the maximum passenger and cargo space for a given size vehicle.

Gilmour, J. L.

1980-01-01

11

Advances in fuel cell vehicle design  

NASA Astrophysics Data System (ADS)

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 to any system utilizing the novel battery-ultracapacitor energy storage system and is not limited in application to only fuel cell vehicles. With regards to DC/DC converters, it is important to design efficient and light-weight converters for use in fuel cell and other electric vehicles to improve overall vehicle fuel economy. Thus, this research presents a novel soft-switching method, the capacitor-switched regenerative snubber, for the high-power DC/DC boost converters commonly used in fuel cell vehicles. This circuit is shown to increase the efficiency and reduce the overall mass of the DC/DC boost converter.

Bauman, Jennifer

12

Automated mixed traffic vehicle design AMTV 2  

NASA Technical Reports Server (NTRS)

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.

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

1982-01-01

13

Space transportation vehicle design evaluation using saturated designs  

Microsoft Academic Search

An important objective in the preliminary design and evaluation of space transportation vehicles is to find the best values of design variables that optimize the performance characteristic (e.g. dry weight). For a given configuration, the vehicle performance can be determined by the use of complex sizing and performance evaluation computer programs. These complex computer programs utilize iterative algorithms and they

Resit Unal

1993-01-01

14

Optimization methods applied to hybrid vehicle design  

NASA Technical Reports Server (NTRS)

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.

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

1983-01-01

15

Vehicle Following Control Design for Automated Highway Systems  

E-print Network

Vehicle Following Control Design for Automated Highway Systems H. Raza and P. Ioannou A, utomatic vehicle following isan important feature of a fully rpartially automated highwaysystem (AHS).Theon-board vehicle controlsystemshouldbeable toaccept and process inputsfrom the driver, theinfrastructure

Ioannou, Petros

16

A method of vehicle active suspension design  

Microsoft Academic Search

This paper contributes to the design of active suspension systems, by the use of spatial vehicle model, without filtered feedback of the control system. A method of stochastic parameters optimisation has been utilized for the optimisation of the parameters of active suspension. The optimisation objective was simultaneous minimization of sprung mass vibration and standard deviation of forces in tire-to-ground contact

M. Demi?; I. Demi?; . Diligenski

2006-01-01

17

Airbreathing hypersonic vehicle design and analysis methods  

NASA Technical Reports Server (NTRS)

The design, analysis, and optimization of airbreathing hypersonic vehicles requires analyses involving many highly coupled disciplines at levels of accuracy exceeding those traditionally considered in a conceptual or preliminary-level design. Discipline analysis methods including propulsion, structures, thermal management, geometry, aerodynamics, performance, synthesis, sizing, closure, and cost are discussed. Also, the on-going integration of these methods into a working environment, known as HOLIST, is described.

Lockwood, Mary Kae; Petley, Dennis H.; Hunt, James L.; Martin, John G.

1996-01-01

18

Space Vehicle Terrestrial Environment Design Requirements Guidelines  

NASA Technical Reports Server (NTRS)

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.

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

2006-01-01

19

Space vehicle meteoroid shielding design  

NASA Technical Reports Server (NTRS)

Design principles of spaced, multiwall meteoroid protection are investigated in the light of experimental data generated during the Apollo Program. The outer wall or shield is shown to be the most important element in the meteoroid-spacecraft interaction. The condition of the debris is primarily a function of the shock pressure, the melting points of the meteoroid and the shield, and the length of the meteoroid and thickness of the shield. Spacing between the walls is effective up to approximately 100 times the length of the meteoroid. The required thickness of the second wall is shown to be proportional to the meteoroid mass, velocity, and density, and to the spacing between the walls, taken with exponents dependent upon the condition of the debris. The effects of placing additional elements (insulation or honeycomb cells) between the two walls are discussed, and the efficiency of various protective configurations is presented. An analysis of the meteoroid protection proposed for the Comet Halley probe is included as an appendix.

Cour-Palais, B. G.

1979-01-01

20

Department of Mechanical Engineering Spring 2012 Space Vehicle Water Drop Test and Vehicle Design  

E-print Network

PENNSTATE Department of Mechanical Engineering Spring 2012 Space Vehicle Water Drop Test and Vehicle Design Overview The team was tasked with modelling the accelerations and pressures of an impact of the scaled landing vehicle to reduce the accelerations and pressures of the vehicle. Objectives Provide

Demirel, Melik C.

21

A lunar construction shack vehicle: Final design  

NASA Technical Reports Server (NTRS)

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.

1988-01-01

22

Design and Implementation of Lab. Simulator for Vehicle Control  

Microsoft Academic Search

The Lab. simulator for conducting a performance test and a reliability test on a vehicle and components has been designed and embodied. In order to control non-linear of a vehicle, a fuzzy control algorithm, a running mode tracking algorithm and a vehicle speed control algorithm were applied to the actuator control. The vehicle controller functions were implemented; setup of the

Jeongdai Jo; Dong-Soo Kim; Kwang-Young Kim; Hyung-Eui Kim

2005-01-01

23

Space transportation vehicle design evaluation using saturated designs  

NASA Technical Reports Server (NTRS)

An important objective in the preliminary design and evaluation of space transportation vehicles is to find the best values of design variables that optimize the performance characteristic (e.g. dry weight). For a given configuration, the vehicle performance can be determined by the use of complex sizing and performance evaluation computer programs. These complex computer programs utilize iterative algorithms and they are generally too expensive and/or difficult to use directly in multidisciplinary design optimization. An alternative is to use response surface methodology (RSM) and obtain quadratic polynomial approximations to the functional relationships between performance characteristics and design variables. In RSM, these approximation models are then used to determine optimum design parameter values and for rapid sensitivity studies. Constructing a second-order model requires that 'n' design parameters be studied at least at 3 levels (values) so that the coefficients in the model can be estimated. There, 3(n) factorial experiments (point designs or observations) may be necessary. For small values of 'n' such as two or three, this design works well. However, when a large number of design parameters are under study, the number of design points required for a full-factorial design may become excessive. Fortunately, these quadratic polynomial approximations can be obtained by selecting an efficient design matrix using central composite designs (CCD) from design of experiments theory. Each unique point design from the CCD matrix is then conducted using computerized analysis tools (e.g. POST, CONSIZ, etc.). In the next step, least squares regression analysis is used to calculate the quadratic polynomial coefficients from the data. However, in some multidisciplinary applications involving a large number of design variables and several disciplines, the computerized performance synthesis programs may get too time consuming and expensive to run even with the use of efficient central composite designs. In such cases, it may be preferable to keep the number of design points to an absolute minimum and trade some model accuracy with cost. For this purpose, another class of experimental designs, called saturated D-optimal designs may be utilized for generating a matrix of vehicle designs. A design is called saturated when the number of design points is exactly equal to the number of terms in the model to be fitted. As a result, saturated designs require the absolute minimum number of design points ((n+1)(n+2)/s) to estimate the quadratic polynomial model coefficients. Saturated designs can be generated using the D-optimality criterion. A good saturated design should give rise to least squares estimates with minimum generalized variance.

Unal, Resit

1993-01-01

24

Vehicle following controller design for autonomous intelligent vehicles  

NASA Technical Reports Server (NTRS)

A new vehicle following controller is proposed for autonomous intelligent vehicles. The proposed vehicle following controller not only provides smooth transient maneuvers for unavoidable nonzero initial conditions but also guarantees the asymptotic platoon stability without the availability of feedforward information. Furthermore, the achieved asymptotic platoon stability is shown to be robust to sensor delays and an upper bound for the allowable sensor delays is also provided in this paper.

Chien, C. C.; Lai, M. C.; Mayr, R.

1994-01-01

25

Design Methodology for Unmannded Aerial Vehicle (UAV) Team Coordination  

E-print Network

1 Design Methodology for Unmannded Aerial Vehicle (UAV) Team Coordination F.B. da Silva S.D. Scott-mail: halab@mit.edu #12;2 Design Methodology for Unmannded Aerial Vehicle (UAV) Team Coordination by F.B. da Silva, S.D. Scott, and M.L. Cummings Executive Summary Unmanned Aerial Vehicle (UAV) systems, despite

Cummings, Mary "Missy"

26

Aeroshell Design Techniques for Aerocapture Entry Vehicles  

NASA Technical Reports Server (NTRS)

A major goal of NASA s In-Space Propulsion Program is to shorten trip times for scientific planetary missions. To meet this challenge arrival speeds will increase, requiring significant braking for orbit insertion, and thus increased deceleration propellant mass that may exceed launch lift capabilities. A technology called aerocapture has been developed to expand the mission potential of exploratory probes destined for planets with suitable atmospheres. Aerocapture inserts a probe into planetary orbit via a single pass through the atmosphere using the probe s aeroshell drag to reduce velocity. The benefit of an aerocapture maneuver is a large reduction in propellant mass that may result in smaller, less costly missions and reduced mission cruise times. The methodology used to design rigid aerocapture aeroshells will be presented with an emphasis on a new systems tool under development. Current methods for fast, efficient evaluations of structural systems for exploratory vehicles to planets and moons within our solar system have been under development within NASA having limited success. Many systems tools that have been attempted applied structural mass estimation techniques based on historical data and curve fitting techniques that are difficult and cumbersome to apply to new vehicle concepts and missions. The resulting vehicle aeroshell mass may be incorrectly estimated or have high margins included to account for uncertainty. This new tool will reduce the guesswork previously found in conceptual aeroshell mass estimations.

Dyke, R. Eric; Hrinda, Glenn A.

2004-01-01

27

Aerospace vehicle design, spacecraft section. Volume 1  

NASA Technical Reports Server (NTRS)

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.

1988-01-01

28

Wooden Spaceships: Human-Centered Vehicle Design for Space  

NASA Technical Reports Server (NTRS)

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.

Twyford, Evan

2009-01-01

29

Configuration Design of the Adaptive Suspension Vehicle  

Microsoft Academic Search

The selection of vehicle and leg configuration and of power transmission and actuation system configuration for the adaptive suspension vehicle (ASV) are discussed. The ASV will be a proof-of-concept prototype of a proposed class of transportation vehicles for use in terrain that is not passable for conventional vehicles. It uses a legged locomotion princi ple. The machine will not be

Kenneth J. Waldron; Vincent J. Vohnout; Arrie Pery; Robert B. McGhee

1984-01-01

30

Orbital Maneuvering Vehicle space station communications design  

NASA Technical Reports Server (NTRS)

The authors present an Orbital Maneuvering Vehicle space station communications systems design approach which is intended to satisfy the stringent link requirements. The operational scenario, system configuration, signal design, antenna system management, and link performance analysis are discussed in detail. It is shown that the return link can transmit up to 21.6 Mb/s and maintain at least a 3-dB link margin through proper power and antenna management control at a maximum distance of 37 km. It is suggested that the proposed system, which is compatible with the space station multiple-access system, can be a model for other space station interoperating elements or users to save the development cost and reduce the technical and schedule risks.

Arndt, D.; Novosad, S. W.; Tu, K.; Loh, Y. C.; Kuo, Y. S.

1988-01-01

31

Design of Flight Vehicle Management Systems  

NASA Technical Reports Server (NTRS)

As the operation of large systems becomes ever more dependent on extensive automation, the need for an effective solution to the problem of design and validation of the underlying software becomes more critical. Large systems possess much detailed structure, typically hierarchical, and they are hybrid. Information processing at the top of the hierarchy is by means of formal logic and sentences; on the bottom it is by means of simple scalar differential equations and functions of time; and in the middle it is by an interacting mix of nonlinear multi-axis differential equations and automata, and functions of time and discrete events. The lecture will address the overall problem as it relates to flight vehicle management, describe the middle level, and offer a design approach that is based on Differential Geometry and Discrete Event Dynamic Systems Theory.

Meyer, George; Aiken, Edwin W. (Technical Monitor)

1994-01-01

32

Computational Aerothermodynamic Design Issues for Hypersonic Vehicles  

NASA Technical Reports Server (NTRS)

A brief review of the evolutionary progress in computational aerothermodynamics is presented. The current status of computational aerothermodynamics is then discussed, with emphasis on its capabilities and limitations for contributions to the design process of hypersonic vehicles. Some topics to be highlighted include: (1) aerodynamic coefficient predictions with emphasis on high temperature gas effects; (2) surface heating and temperature predictions for thermal protection system (TPS) design in a high temperature, thermochemical nonequilibrium environment; (3) methods for extracting and extending computational fluid dynamic (CFD) solutions for efficient utilization by all members of a multidisciplinary design team; (4) physical models; (5) validation process and error estimation; and (6) gridding and solution generation strategies. Recent experiences in the design of X-33 will be featured. Computational aerothermodynamic contributions to Mars Path finder, METEOR, and Stardust (Comet Sample return) will also provide context for this discussion. Some of the barriers that currently limit computational aerothermodynamics to a predominantly reactive mode in the design process will also be discussed, with the goal of providing focus for future research.

Gnoffo, Peter A.; Weilmuenster, K. James; Hamilton, H. Harris, II; Olynick, David R.; Venkatapathy, Ethiraj

2005-01-01

33

Computational Aerothermodynamic Design Issues for Hypersonic Vehicles  

NASA Technical Reports Server (NTRS)

A brief review of the evolutionary progress in computational aerothermodynamics is presented. The current status of computational aerothermodynamics is then discussed, with emphasis on its capabilities and limitations for contributions to the design process of hypersonic vehicles. Some topics to be highlighted include: (1) aerodynamic coefficient predictions with emphasis on high temperature gas effects; (2) surface heating and temperature predictions for thermal protection system (TPS) design in a high temperature, thermochemical nonequilibrium environment; (3) methods for extracting and extending computational fluid dynamic (CFD) solutions for efficient utilization by all members of a multidisciplinary design team; (4) physical models; (5) validation process and error estimation; and (6) gridding and solution generation strategies. Recent experiences in the design of X-33 will be featured. Computational aerothermodynamic contributions to Mars Pathfinder, METEOR, and Stardust (Comet Sample return) will also provide context for this discussion. Some of the barriers that currently limit computational aerothermodynamics to a predominantly reactive mode in the design process will also be discussed, with the goal of providing focus for future research.

Olynick, David R.; Venkatapathy, Ethiraj

2004-01-01

34

Computational Aerothermodynamic Design Issues for Hypersonic Vehicles  

NASA Technical Reports Server (NTRS)

A brief review of the evolutionary progress in computational aerothermodynamics is presented. The current status of computational aerothermodynamics is then discussed, with emphasis on its capabilities and limitations for contributions to the design process of hypersonic vehicles. Some topics to be highlighted include: (1) aerodynamic coefficient predictions with emphasis on high temperature gas effects; (2) surface heating and temperature predictions for thermal protection system (TPS) design in a high temperature, thermochemical nonequilibrium environment; (3) methods for extracting and extending computational fluid dynamic (CFD) solutions for efficient utilization by all members of a multidisciplinary design team; (4) physical models; (5) validation process and error estimation; and (6) gridding and solution generation strategies. Recent experiences in the design of X-33 will be featured. Computational aerothermodynamic contributions to Mars Pathfinder, METEOR, and Stardust (Comet Sample return) will also provide context for this discussion. Some of the barriers that currently limit computational aerothermodynamics to a predominantly reactive mode in the design process will also be discussed, with the goal of providing focus for future research.

Gnoffo, Peter A.; Weilmuenster, K. James; Hamilton, H. Harris, II; Olynick, David R.; Venkatapathy, Ethiraj

1997-01-01

35

Mechatronic design and control of hybrid electric vehicles  

Microsoft Academic Search

The work in this paper presents techniques for design, development, and control of hybrid electric vehicles (HEV). Toward these ends, four issues are explored. First, the development of HEV is presented. This synopsis includes a novel definition of degree of hybridization for automotive vehicles. Second, a load-leveling vehicle operation strategy is developed. In order to accomplish the strategy, a fuzzy

Bernd M. Baumann; Gregory Washington; Bradley C. Glenn; Giorgio Rizzoni

2000-01-01

36

Online Mechanism Design for Electric Vehicle Charging Enrico H. Gerding  

E-print Network

Online Mechanism Design for Electric Vehicle Charging Enrico H. Gerding eg@ecs.soton.ac.uk Valentin electric vehicles are expected to place a consid- erable strain on local electricity distribution networks mechanisms are evaluated in depth, using data from a real-world trial of electric vehicles in the UK

Chen, Yiling

37

Optimal Power Train Design of a Hybrid Refuse Collector Vehicle  

E-print Network

Optimal Power Train Design of a Hybrid Refuse Collector Vehicle Tobias Knoke, Joachim Böcker 5251 60 2212 Abstract-- Due to the stop-and-go drive cycle of refuse collector vehicles, hybrid power as an optimization problem with the objectives "minimize fuel consumption" and "minimize vehicle weight

Paderborn, Universität

38

Improved Design of Vehicle Management System Based on RFID  

Microsoft Academic Search

This paper conducts an investigation in the domestic vehicle management standards and proposes an improved design of vehicle management system based on RFID technology. The system improves vehicle management systems in the domain of system security, data acquisition, statistical analysis, remote computer monitoring and hand-held card reader applications by integrating RFID technology with network communication technology, database technology and embedded

Jiang Lin-ying; Wang Shuai; Zhang Heng; Tan Han-qing

2010-01-01

39

Design and Implement of Vehicle Dynamic Weighing System  

Microsoft Academic Search

In view of the current damage roads and bridges caused by overloaded vehicles, through analyzing the factors affecting the weight of vehicles in process of weighing, the vehicle dynamic weighing protect system has been designed. Based on DSP controller, MODEM communication interface, the ADS1255 high-precision sampling, use of linear regression method to establish a compensation rate of compensation factor model.

Gaohua Liao; Junmei Xi

2010-01-01

40

CONCEPTUAL DESIGNS FOR A NEW HIGHWAY VEHICLE EMISSIONS ESTIMATION METHODOLOGY  

EPA Science Inventory

The report discusses six conceptual designs for a new highway vehicle emissions estimation methodology and summarizes the recommendations of each design for improving the emissions and activity factors in the emissions estimation process. he complete design reports are included a...

41

Conceptual design of a hybrid electric off-road vehicle  

Microsoft Academic Search

This paper presents the conceptual design of a hybrid electric off-road vehicle. The vehicle is intended to be used in Colombia (South America) where the topographical conditions require special considerations for the design of the critical systems. A study and preliminary design of the power supply system, the suspension and the powertrain are presented.

L. E. Munoz; J. C. Blanco; J. P. Barreto; N. A. Rincon; S. D. Roa

2012-01-01

42

Accelerating the Design of Space Vehicles  

NASA Technical Reports Server (NTRS)

One of NASA's key goals is to increase the safety and reduce the cost of space transportation. Thus, a key element of NASA's new Integrated Space Transportation Plan is to develop new propulsion, structures, and operations for future generations of reusable launch vehicles (RLVs). As part of this effort to develop the next RLV, the ClCT Program's Computing, Networking, and Information Systems (CNIS) Project is developing and demonstrating collaborative software technologies that use the collective power of the NASA Grid to accelerate spacecraft design. One of these technologies, called AeroDB, automates the execution and monitoring of computational fluid dynamics (CFD) parameter studies on the NASA Grid. About the NASA Grid The NASA Grid, or Information Power Grid,. is being developed to leverage the distributed resources of NASA's many computers. instruments, simulators, and data storage systems. The goal is to use these combined resources to sdve difficult NASA challenges, such as iimulating the entire flight of a space vehicle from ascent to descent.To realize the vision of the NASA Grid, the CNIS Project is developing the software framework and protocols for building domain-specific environments and interfaces, new Grid services based on emerging industry standards, and advanced networking and computing testbeds to support new Grid-based applications such as AeroDB.

Laufenberg, Larry (Editor)

2003-01-01

43

Propulsion system design of electric and hybrid vehicles  

Microsoft Academic Search

There is a growing interest in electric and hybrid-electric vehicles due to environmental concerns. Efforts are directed toward developing an improved propulsion system for electric and hybrid-electric vehicles applications. This paper is aimed at developing the system design philosophies of electric and hybrid vehicle propulsion systems. The vehicles' dynamics are studied in an attempt to find an optimal torque-speed profile

Mehrdad Ehsani; Khwaja M. Rahman; Hamid A. Toliyat

1997-01-01

44

Design Optimization of Vehicle Control Networks  

Microsoft Academic Search

The advancement of electronic technology has made significant contributions to the safety and convenience of modern vehicles. New intelligent functionalities of vehicles have been im- plemented in a number of electronic control units (ECUs) that are connected to each in vehicle control networks (VCNs). However, with the rapid increase in the number of ECUs, VCNs currently face several challenges, e.g.,

Seongwoo Kim; Eundong Lee; Mideum Choi; Hanyou Jeong; Seungwoo Seo

2011-01-01

45

Nonlinear Control Design for a Supercavitating Vehicle  

Microsoft Academic Search

Supercavitating vehicles can achieve very high speed but also pose technical challenges in system stability, maneuvering, and control. Compared to a fully-wetted vehicle for which substantial lift is generated due to vortex shedding off the hull, a supercavitating vehicle is enveloped by gas surface (cavity) and thus the lift is provided by control surface deflections of the cavitator and fins,

Xiaofeng Mao; Qian Wang

2009-01-01

46

Preventing Passenger Vehicle Occupant Injuries by Vehicle DesignA Historical Perspective from IIHS  

Microsoft Academic Search

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 countermeasuredesigning vehicles that reduce occupant deaths and injuries. For many years, people had urged automakers to add design features to

Brian ONeill

2009-01-01

47

Gain-scheduled reusable launch vehicle attitude controller design  

Microsoft Academic Search

A new kind of gain-scheduled attitude controller for reusable launch vehicle is presented. In this paper, gain-scheduled controller design is finished without considering small perturbation linearization. Simultaneously, coordinated scheduling controller is used to deal with intentionally cross coupling. This framework is applied to the design of coupling between roll, pitch and yaw of reusable launch vehicle with large angles of

Nai-gang Cui; Jiangtao Xu; Rongjun Mu; Pengxin Han

2009-01-01

48

Integrated structural and thermal design of an entry vehicle aeroshell  

E-print Network

, a graphite / epoxy composite structure was designed based on the primary load conditions. Next, a thermal protection system (TPS) was added to the exterior of the vehicle. The second design featured a structurally integrated TPS. This new approach...

Cochran, David Brian

1996-01-01

49

Defining Support Requirements During Conceptual Design of Reusable Launch Vehicles  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

50

43 CFR 420.21 - Procedure for designating areas for off-road vehicle use.  

Code of Federal Regulations, 2013 CFR

...Procedure for designating areas for off-road vehicle use. 420.21 Section 420...DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE Designated Areas and Permitted...Procedure for designating areas for off-road vehicle use. The...

2013-10-01

51

43 CFR 420.21 - Procedure for designating areas for off-road vehicle use.  

Code of Federal Regulations, 2011 CFR

...Procedure for designating areas for off-road vehicle use. 420.21 Section 420...DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE Designated Areas and Permitted...Procedure for designating areas for off-road vehicle use. The...

2011-10-01

52

43 CFR 420.21 - Procedure for designating areas for off-road vehicle use.  

Code of Federal Regulations, 2012 CFR

...Procedure for designating areas for off-road vehicle use. 420.21 Section 420...DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE Designated Areas and Permitted...Procedure for designating areas for off-road vehicle use. The...

2012-10-01

53

43 CFR 420.21 - Procedure for designating areas for off-road vehicle use.  

...Procedure for designating areas for off-road vehicle use. 420.21 Section 420...DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE Designated Areas and Permitted...Procedure for designating areas for off-road vehicle use. The...

2014-10-01

54

43 CFR 420.21 - Procedure for designating areas for off-road vehicle use.  

Code of Federal Regulations, 2010 CFR

...Procedure for designating areas for off-road vehicle use. 420.21 Section 420...DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE Designated Areas and Permitted...Procedure for designating areas for off-road vehicle use. The...

2010-10-01

55

Two designs for an orbital transfer vehicle  

NASA Technical Reports Server (NTRS)

The Orbital Transfer Vehicle (OTV) and systems were researched in the following areas: avionics, crew systems, electrical power systems, environmental control/life support systems, navigation and orbital maneuvers, propulsion systems, reaction control systems (RCS), servicing systems, and structures.

Davis, Richard; Duquette, Miles; Fredrick, Rebecca; Schumacher, Daniel; Somers, Schaeffer; Stafira, Stanley; Williams, James; Zelinka, Mark

1988-01-01

56

DESIGN OF A REMOTELY CONTROLLED HOVERCRAFT VEHICLE FOR SPILL RECONNAISSANCE  

EPA Science Inventory

This program was undertaken to prepare a conceptual design for a practical prototype of a remotely-controlled reconnaissance vehicle for use in hazardous material spill environment. Data from past hazardous material spills were analyzed to determine the type of vehicle best suite...

57

Powertrain Design for Shell Eco-marathon UrbanConcept Vehicle The team was tasked with designing the powertrain for a highly fuel efficient vehicle. The  

E-print Network

Powertrain Design for Shell Eco-marathon UrbanConcept Vehicle Overview The team was tasked with designing the powertrain for a highly fuel efficient vehicle. The vehicle was designed to conform possible fuel efficiency. Finally, the team transported the vehicle to Houston, Texas and successfully

Demirel, Melik C.

58

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

NASA Technical Reports Server (NTRS)

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.

1979-01-01

59

Model-Based Control Design of Integrated Vehicle Systems  

Microsoft Academic Search

This paper presents a model-based control design for an integrated vehicle system in which several active components are operated\\u000a in co-operation. In control-oriented modeling vehicle dynamics is augmented with the performance specifications of the controlled\\u000a system and the uncertainties of the model. In control design performance specifications must be formalized in such a way that\\u000a the performance demands are guaranteed,

Pter Gspr

60

Design considerations for a contactless electric vehicle battery charger  

Microsoft Academic Search

This paper overviews theoretical and practical design issues related to inductive power transfer systems and verifies the developed theory using a practical electric vehicle battery charger. The design focuses on the necessary approaches to ensure power transfer over the complete operating range of the system. As such, a new approach to the design of the primary resonant circuit is proposed,

Chwei-Sen Wang; Oskar H. Stielau; Grant A. Covic

2005-01-01

61

Design and analysis of a gyroscopically controlled micro air vehicle  

NASA Astrophysics Data System (ADS)

Much of the current research on micro air vehicle design relies on aerodynamic forces for attitude control. The aerodynamic environment in which micro air vehicles operate is characterized by a low Reynolds number and is not fully understood, resulting in decreased performance and efficiency when compared to large-scale vehicles. In this work, we propose a new rotary-wing micro air vehicle design that utilizes gyroscopic dynamics for attitude control. Unlike traditional micro air vehicles where attitude control moments are generated by aerodynamic control surfaces, the proposed vehicle will leverage the existing angular momentum of its rotating components to generate gyroscopic moments for controlling attitude. We explore this paradigm in an effort to reduce mechanical complexity that is inherent in blade pitch modulation mechanisms such as the swashplate, and to increase agility and possibly even efficiency when compared to state-of-the-art micro vertical-take-off-and-landing vehicles. The evolution of the mechanical design, including the evaluation of three prototypes that explore the use of gyroscopic attitude control, is presented along with a comprehensive dynamic and aerodynamic model of the third prototype. Two controllers that utilize gyroscopic moments are developed and tested in simulation. In addition, several experiments were performed using a VICON motion tracking system and off-board control. These results will also be presented.

Thorne, Christopher Everett

62

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

PubMed

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 and chest injury measures recorded on driver and front-seat test dummies. NHTSA later added side crash tests and rollover ratings to the U.S. NCAP. Consumer crash testing spread worldwide in the 1990s. In 1995, the Insurance Institute for Highway Safety (IIHS) began using frontal offset crash tests to rate and compare frontal crashworthiness and later added side and rear crash assessments. Shortly after, Europe launched EuroNCAP to assesses new car performance including front, side, and front-end pedestrian tests. The influence of these consumer-oriented crash test programs on vehicle designs has been major. From the beginning, U.S. NCAP results prompted manufacturers to improve seat belt performance. Frontal offset tests from IIHS and EuroNCAP resulted in greatly improved front-end crumple zones and occupant compartments. Side impact tests have similarly resulted in improved side structures and accelerated the introduction of side impact airbags, especially those designed to protect occupant's heads. Vehicle safety designs, initially driven by regulations and later by consumer demand because of crash testing, have proven to be very successful public health measures. Since they were first introduced in the late 1960s, vehicle safety designs have saved hundreds of thousands of lives and prevented countless injuries worldwide. The designs that improved vehicle crashworthiness have been particularly effective. Some newer crash avoidance designs also have the potential to be effective-e.g., electronic stability control is already saving many lives in single-vehicle crashes. However, determining the actual effectiveness of these new technologies is a slow process and needs real-world crash experience because there are no assessment equivalent of crash tests for crash avoidance designs. PMID:19333823

O'Neill, Brian

2009-04-01

63

Conceptual design of flapping-wing micro air vehicles.  

PubMed

Traditional micro air vehicles (MAVs) are miniature versions of full-scale aircraft from which their design principles closely follow. The first step in aircraft design is the development of a conceptual design, where basic specifications and vehicle size are established. Conceptual design methods do not rely on specific knowledge of the propulsion system, vehicle layout and subsystems; these details are addressed later in the design process. Non-traditional MAV designs based on birds or insects are less common and without well-established conceptual design methods. This paper presents a conceptual design process for hovering flapping-wing vehicles. An energy-based accounting of propulsion and aerodynamics is combined with a one degree-of-freedom dynamic flapping model. Important results include simple analytical expressions for flight endurance and range, predictions for maximum feasible wing size and body mass, and critical design space restrictions resulting from finite wing inertia. A new figure-of-merit for wing structural-inertial efficiency is proposed and used to quantify the performance of real and artificial insect wings. The impact of these results on future flapping-wing MAV designs is discussed in detail. PMID:22498507

Whitney, J P; Wood, R J

2012-09-01

64

Design study of toroidal traction CVT for electric vehicles  

NASA Technical Reports Server (NTRS)

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.

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

1980-01-01

65

Application of optimization techniques to vehicle design: A review  

NASA Technical Reports Server (NTRS)

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.

Prasad, B.; Magee, C. L.

1984-01-01

66

Design Criteria for Low Risk Re-Entry Vehicles  

NASA Astrophysics Data System (ADS)

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).

Monti, R.; Pezzella, G.

2005-02-01

67

Conceptual Launch Vehicle and Spacecraft Design for Risk Assessment  

NASA Technical Reports Server (NTRS)

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 innovative risk assessment capabilities.

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

2014-01-01

68

Design principles of descent vehicles with an inflatable braking device  

NASA Astrophysics Data System (ADS)

A new type of descent vehicle (DVs) is described: a descent vehicle with an inflatable braking device (IBD DV). IBD development issues, as well as materials needed for the design, manufacturing, and testing of an IBD and its thermal protection, are discussed. A list is given of Russian integrated test facilities intended for testing IBD DVs. Progress is described in the development of IBD DVs in Russia and abroad.

Alexashkin, S. N.; Pichkhadze, K. M.; Finchenko, V. S.

2013-12-01

69

Design of a recovery system for a reentry vehicle  

Microsoft Academic Search

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

Wulf von Eckroth; William L. Garrard; Norman Miller

1993-01-01

70

Vehicle design and thermal comfort of poultry in transit.  

PubMed

1. Four second-generation artificial chickens (Glorias) simulated the sensible heat exchanges, H, of pullets and end-of-lay hens which they accompanied throughout commercial transit in different sites of the loads. 2. Data from two summer and two winter journeys on each of 5 naturally- and 2 fan-ventilated vehicles were used to derive general equations to predict H and temperature lift for each vehicle. 3. From these, air movement, V, within the crates was calculated together with predicted H at ambient temperatures to compare the thermal comfort of the vehicles. 4. All naturally-ventilated vehicles were over-ventilated in motion, with mean V ranging from 0.9 to 2.4 m/s within the crate, and maximum V of 6.0 m/s resulting in negligible temperature lift above ambient. Poorly-feathered hens were, consequently, extremely cold-stressed in winter. When stationary, vehicles with a central passage that enabled the 'stack effect' to operate were thermally comfortable provided V was kept low. Designs stocked over the whole floor area of the vehicle were too hot. 5. Fan-ventilated vehicles had a similar range of H whether stationary or in motion. The mean V of 1 to 2 m/s of bird-warmed air maintained satisfactory thermal conditions most of the time. 6. For current designs of poultry vehicle stocked at commercial rates, V should normally be between 0.3 and 1.0 m/s; air temperature near pullets or broilers should be 10-15 degrees C and near poorly-feathered hens 22-28 degrees C. Suitable ventilation rates are likely to be in the range 100 to 600 m3 per hour. It is strongly recommended that appropriate temperature monitoring systems be fitted on all vehicles. PMID:9510988

Weeks, C A; Webster, A J; Wyld, H M

1997-12-01

71

Design optimization of space launch vehicles using a genetic algorithm  

NASA Astrophysics Data System (ADS)

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.

Bayley, Douglas James

72

Design study of flat belt CVT for electric vehicles  

NASA Technical Reports Server (NTRS)

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.

Kumm, E. L.

1980-01-01

73

Design of a recovery system for a reentry vehicle  

NASA Astrophysics Data System (ADS)

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.

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

74

Fire hazard considerations for composites in vehicle design  

NASA Technical Reports Server (NTRS)

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.

Gordon, Rex B.

1994-01-01

75

Modular design of the LED vehicle projector headlamp system.  

PubMed

A well designed headlamp for a vehicle lighting system is very important as it provides drivers with safe and comfortable driving conditions at night or in dark places. With the advances of the semiconductor technology, the LED has become the fourth generation lighting source in the auto industry. In this study, we will propose a LED vehicle projector headlamp system. This headlamp system contains several LED headlamp modules, and every module of it includes four components: focused LEDs, asymmetric metal-based plates, freeform surfaces, and condenser lenses. By optimizing the number of LED headlamp modules, the proposed LED vehicle projector headlamp system has only five LED headlamp modules. It not only provides the low-beam cutoff without a shield, but also meets the requirements of the ECE R112 regulation. Finally, a prototype of the LED vehicle projector headlamp system was assembled and fabricated to create the correct light pattern. PMID:23872770

Hsieh, Chi-Chang; Li, Yan-Huei; Hung, Chih-Ching

2013-07-20

76

Systems design analysis applied to launch vehicle configuration  

NASA Technical Reports Server (NTRS)

As emphasis shifts from optimum-performance aerospace systems to least lift-cycle costs, systems designs must seek, adapt, and innovate cost improvement techniques in design through operations. The systems design process of concept, definition, and design was assessed for the types and flow of total quality management techniques that may be applicable in a launch vehicle systems design analysis. Techniques discussed are task ordering, quality leverage, concurrent engineering, Pareto's principle, robustness, quality function deployment, criteria, and others. These cost oriented techniques are as applicable to aerospace systems design analysis as to any large commercial system.

Ryan, R.; Verderaime, V.

1993-01-01

77

MIT Electric Vehicle Team Porsche designing a cooling system for the AC24 electric motor  

E-print Network

In this thesis I worked on the design and analysis of a cooling system for the electric motor of the MIT Electric Vehicle Team's Porsche 914 Battery Electric Vehicle. The vehicle's Azure Dynamics AC24 motor tended to ...

Meenen, Jordan N

2010-01-01

78

19 CFR 115.65 - Technical requirements for road vehicles by design type.  

...SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION...Technical requirements for road vehicles by design type. The plans and specifications...contained in 115.64, and the one or more road vehicles that are...

2014-04-01

79

19 CFR 115.65 - Technical requirements for road vehicles by design type.  

Code of Federal Regulations, 2011 CFR

...SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION...Technical requirements for road vehicles by design type. The plans and specifications...contained in 115.64, and the one or more road vehicles that are...

2011-04-01

80

19 CFR 115.65 - Technical requirements for road vehicles by design type.  

Code of Federal Regulations, 2010 CFR

...SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION...Technical requirements for road vehicles by design type. The plans and specifications...contained in 115.64, and the one or more road vehicles that are...

2010-04-01

81

19 CFR 115.65 - Technical requirements for road vehicles by design type.  

Code of Federal Regulations, 2013 CFR

...SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION...Technical requirements for road vehicles by design type. The plans and specifications...contained in 115.64, and the one or more road vehicles that are...

2013-04-01

82

19 CFR 115.65 - Technical requirements for road vehicles by design type.  

Code of Federal Regulations, 2012 CFR

...SECURITY; DEPARTMENT OF THE TREASURY CARGO CONTAINER AND ROAD VEHICLE CERTIFICATION...Technical requirements for road vehicles by design type. The plans and specifications...contained in 115.64, and the one or more road vehicles that are...

2012-04-01

83

Towards Comprehensive Variation Models for Designing Vehicle Monitoring Systems  

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

84

A comparison of hydrogen, methanol and gasoline as fuels for fuel cell vehicles: implications for vehicle design and infrastructure development  

Microsoft Academic Search

All fuel cells cuuenuy being developed for near term use in electric vehicles require hydrogen as a fuel. Hydrogen can be stored directly or produced onboard the vehicle by reforming methanol. or hydrocarbon fuels derived from crude oil (e.g.. gasoline. diesel. or middle distillates). The vehicle design is simpler with direct hydrogen storage. but requires developing a more complex refueling

Joan M. Ogden; Margaret M. Steinbugler; Thomas G. Kreutz

1999-01-01

85

Off-road perception testbed vehicle design and evaluation  

NASA Astrophysics Data System (ADS)

Off-road robotics efforts such as DARPA"s PerceptOR program have motivated the development of testbed vehicles capable of sustained operation in a variety of terrain and environments. This paper describes the retrofitting of a minimally-modified ATV chassis into such a testbed which has been used by multiple programs for autonomous mobility development and sensor characterization. Modular mechanical interfaces for sensors and equipment enclosures enabled integration of multiple payload configurations. The electric power subsystem was capable of short-term operation on batteries with refueled generation for continuous operation. Processing subsystems were mounted in sealed, shock-dampened enclosures with heat exchangers for internal cooling to protect against external dust and moisture. The computational architecture was divided into a real-time vehicle control layer and an expandable high level processing and perception layer. The navigation subsystem integrated real time kinematic GPS with a three-axis IMU for accurate vehicle localization and sensor registration. The vehicle software system was based on the MarsScape architecture developed under DARPA"s MARS program. Vehicle mobility software capabilities included route planning, waypoint navigation, teleoperation, and obstacle detection and avoidance. The paper describes the vehicle design in detail and summarizes its performance during field testing.

Spofford, John R.; Herron, Jennifer B.; Anhalt, David J.; Morgenthaler, Matthew K.; DeHerrera, Clinton

2003-09-01

86

Overview of integrated programs for aerospace-vehicle design (IPAD)  

NASA Technical Reports Server (NTRS)

An overview of a joint industry/government project, denoted Integrated Programs for Aerospace-Vehicle Design (IPAD), which focuses on development of technology and associated software for integrated company-wide management of engineering information is presented. Results to date are summarized and include an in-depth documentation of a representative design process for a large engineering project, the definition and design of computer-aided design software needed to support that process, and the release of prototype software to integrated selected design functions.

Fulton, R. E.

1980-01-01

87

Reliability-Based Multidisciplinary Design Optimization of Vehicle Structures  

Microsoft Academic Search

1. ABSTRACT Crash Simulation evaluates vehicle crashworthiness for occupant safety. It is a highly undeterministic process due to uncertainty in every aspect, e.g., material, gages, etc. As a result, conventional deterministic optimization may be insufficient for crash problems. In addition, a system approach, which considers multiple crash modes, must be applied for safety, as a design considering only a single

R. J. Yang; L. Gu; C. H. Tho; K. K. Choi; B. D. Youn

88

Methods for Estimating Payload/Vehicle Design Loads  

NASA Technical Reports Server (NTRS)

Several methods compared with respect to accuracy, design conservatism, and cost. Objective of survey: reduce time and expense of load calculation by selecting approximate method having sufficient accuracy for problem at hand. Methods generally applicable to dynamic load analysis in other aerospace and other vehicle/payload systems.

Chen, J. C.; Garba, J. A.; Salama, M. A.; Trubert, M. R.

1983-01-01

89

Multipurpose Uninhabited Air Vehicle (UAV) design and verification  

NASA Astrophysics Data System (ADS)

A multipurpose Uninhabited Air Vehicle was designed and built for the NASA University Research Center. It is capable of carrying a payload of up to 14 lbs with an estimated endurance of 3 hours. This thesis will describe the work that was completed on the aerodynamic and preliminary structural design of the air vehicle. It will be demonstrated how the size and configuration of the airframe were chosen based on the design requirements. The detailed design process will be described to achieve initial performance and mission requirements. Although the URC has successfully constructed airframes in the past, it is the intention of this thesis to also take a different approach on alternative construction methods in an effort to reduce cost and improve aircraft performance.

Barquero, Juan P.

90

Multidisciplinary design optimization of mechatronic vehicles with active suspensions  

NASA Astrophysics Data System (ADS)

A multidisciplinary optimization method is applied to the design of mechatronic vehicles with active suspensions. The method is implemented in a GA-A'GEM-MATLAB simulation environment in such a way that the linear mechanical vehicle model is designed in a multibody dynamics software package, i.e. A'GEM, the controllers and estimators are constructed using linear quadratic Gaussian (LQG) method, and Kalman filter algorithm in Matlab, then the combined mechanical and control model is optimized simultaneously using a genetic algorithm (GA). The design variables include passive parameters and control parameters. In the numerical optimizations, both random and deterministic road inputs and both perfect measurement of full state variables and estimated limited state variables are considered. Optimization results show that the active suspension systems based on the multidisciplinary optimization method have better overall performance than those derived using conventional design methods with the LQG algorithm.

He, Yuping; McPhee, John

2005-05-01

91

Aerospace vehicle design, spacecraft section. Volume 2  

NASA Technical Reports Server (NTRS)

The next major step in the evolution of the space program is the exploration of the planet Mars. In preparation for this, much research is needed on the problem of surveying the planet surface. An aircraft appears to be a viable solution because it can carry men and equipment large distances in a short period of time as compared with ground transportation. The problems and design of an aircraft which would be able to survey the planet Mars are examined.

1988-01-01

92

Application of Adaptive Autopilot Designs for an Unmanned Aerial Vehicle  

NASA Technical Reports Server (NTRS)

This paper summarizes the application of two adaptive approaches to autopilot design, and presents an evaluation and comparison of the two approaches in simulation for an unmanned aerial vehicle. One approach employs two-stage dynamic inversion and the other employs feedback dynamic inversions based on a command augmentation system. Both are augmented with neural network based adaptive elements. The approaches permit adaptation to both parametric uncertainty and unmodeled dynamics, and incorporate a method that permits adaptation during periods of control saturation. Simulation results for an FQM-117B radio controlled miniature aerial vehicle are presented to illustrate the performance of the neural network based adaptation.

Shin, Yoonghyun; Calise, Anthony J.; Motter, Mark A.

2005-01-01

93

Analysis and Design of Launch Vehicle Flight Control Systems  

NASA Technical Reports Server (NTRS)

This paper describes the fundamental principles of launch vehicle flight control analysis and design. In particular, the classical concept of "drift-minimum" and "load-minimum" control principles is re-examined and its performance and stability robustness with respect to modeling uncertainties and a gimbal angle constraint is discussed. It is shown that an additional feedback of angle-of-attack or lateral acceleration can significantly improve the overall performance and robustness, especially in the presence of unexpected large wind disturbance. Non-minimum-phase structural filtering of "unstably interacting" bending modes of large flexible launch vehicles is also shown to be effective and robust.

Wie, Bong; Du, Wei; Whorton, Mark

2008-01-01

94

Considerations on vehicle design criteria for space tourism  

NASA Astrophysics Data System (ADS)

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.

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

1995-10-01

95

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

Microsoft Academic Search

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

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

2010-01-01

96

Entry Vehicle Control System Design for the Mars Smart Lander  

NASA Technical Reports Server (NTRS)

The NASA Langley Research Center, in cooperation with the Jet Propulsion Laboratory, participated in a preliminary design study of the Entry, Descent and Landing phase for the Mars Smart Lander Project. This concept utilizes advances in Guidance, Navigation and Control technology to significantly reduce uncertainty in the vehicle landed location on the Mars surface. A candidate entry vehicle controller based on the Reaction Control System controller for the Apollo Lunar Excursion Module digital autopilot is proposed for use in the entry vehicle attitude control. A slight modification to the phase plane controller is used to reduce jet-firing chattering while maintaining good control response for the Martian entry probe application. The controller performance is demonstrated in a six-degree-of-freedom simulation with representative aerodynamics.

Calhoun, Philip C.; Queen, Eric M.

2002-01-01

97

Design studies of continuously variable transmissions for electric vehicles  

NASA Technical Reports Server (NTRS)

Preliminary design studies were performed on four continuously variable transmission (CVT) concepts for use with a flywheel equipped electric vehicle of 1700 kg gross weight. Requirements of the CVT's were a maximum torque of 450 N-m (330 lb-ft), a maximum output power of 75 kW (100 hp), and a flywheel speed range of 28,000 to 14,000 rpm. Efficiency, size, weight, cost, reliability, maintainability, and controls were evaluated for each of the four concepts which included a steel V-belt type, a flat rubber belt type, a toroidal traction type, and a cone roller traction type. All CVT's exhibited relatively high calculated efficiencies (68 percent to 97 percent) over a broad range of vehicle operating conditions. Estimated weight and size of these transmissions were comparable to or less than equivalent automatic transmission. The design of each concept was carried through the design layout stage.

Parker, R. J.; Loewenthal, S. H.; Fischer, G. K.

1981-01-01

98

Aerodynamic design of electric and hybrid vehicles: A guidebook  

NASA Technical Reports Server (NTRS)

A typical present-day subcompact electric hybrid vehicle (EHV), operating on an SAE J227a D driving cycle, consumes up to 35% of its road energy requirement overcoming aerodynamic resistance. The application of an integrated system design approach, where drag reduction is an important design parameter, can increase the cycle range by more than 15%. This guidebook highlights a logic strategy for including aerodynamic drag reduction in the design of electric and hybrid vehicles to the degree appropriate to the mission requirements. Backup information and procedures are included in order to implement the strategy. Elements of the procedure are based on extensive wind tunnel tests involving generic subscale models and full-scale prototype EHVs. The user need not have any previous aerodynamic background. By necessity, the procedure utilizes many generic approximations and assumptions resulting in various levels of uncertainty. Dealing with these uncertainties, however, is a key feature of the strategy.

Kurtz, D. W.

1980-01-01

99

Design of cryogenic tanks for launch vehicles  

NASA Technical Reports Server (NTRS)

During the period since January 1990, work was concentrated on the problem of the buckling of the structure of an ALS (advanced launch systems) tank during the boost phase. The primary problem was to analyze a proposed hat stringer made by superplastic forming, and to compare it with an integrally stiffened stringer design. A secondary objective was to determine whether structural rings having the identical section to the stringers will provide adequate support against overall buckling. All of the analytical work was carried out with the TESTBED program on the CONVEX computer, using PATRAN programs to create models. Analyses of skin/stringer combinations have shown that the proposed stringer design is an adequate substitute for the integrally stiffened stringer. Using a highly refined mesh to represent the corrugations in the vertical webs of the hat stringers, effective values were obtained for cross-sectional area, moment of inertia, centroid height, and torsional constant. Not only can these values be used for comparison with experimental values, but they can also be used for beams to replace the stringers and frames in analytical models of complete sections of tank. The same highly refined model was used to represent a section of skin reinforced by a stringer and a ring segment in the configuration of a cross. It was intended that this would provide a baseline buckling analysis representing a basic mode, however, the analysis proved to be beyond the scope of the CONVEX computer. One quarter of this model was analyzed, however, to provide information on buckling between the spot welds. Models of large sections of the tank structure were made, using beam elements to model the stringers and frames. In order to represent the stiffening effects of pressure, stresses and deflections under pressure should first be obtained, and then the buckling analysis should be made on the structure so deflected. So far, uncharacteristic deflections under pressure were obtained from the TESTBED program using two types of structural elements. Similar results were obtained using the ANSYS program on a mainframe computer, although two finite element programs on microcomputers have yielded realistic results.

Copper, Charles; Pilkey, Walter D.; Haviland, John K.

1990-01-01

100

Design of a Long Endurance Titan VTOL Vehicle  

NASA Technical Reports Server (NTRS)

Saturn s moon Titan promises insight into many key scientific questions, many of which can be investigated only by in situ exploration of the surface and atmosphere of the moon. This research presents a vertical takeoff and landing (VTOL) vehicle designed to conduct a scientific investigation of Titan s atmosphere, clouds, haze, surface, and any possible oceans. In this investigation, multiple options for vertical takeoff and horizontal mobility were considered. A helicopter was baselined because of its many advantages over other types of vehicles, namely access to hazardous terrain and the ability to perform low speed aerial surveys. Using a nuclear power source and the atmosphere of Titan, a turbo expander cycle produces the 1.9 kW required by the vehicle for flight and operations, allowing it to sustain a long range, long duration mission that could traverse the majority of Titan. Such a power source could increase the lifespan and quality of science for planetary aerial flight to an extent that the limiting factor for the mission life is not available power but the life of the mechanical parts. Therefore, the mission could potentially last for years. This design is the first to investigate the implications of this potentially revolutionary technology on a Titan aerial vehicle.

Prakash, Ravi; Braun, Robert D.; Colby, Luke S.; Francis, Scott R.; Guenduez, Mustafa E.; Flaherty, Kevin W.; Lafleur, Jarret M.; Wright, Henry S.

2006-01-01

101

Kistler reusable vehicle facility design and operational approach  

NASA Astrophysics Data System (ADS)

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.

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

102

Conceptual design of a manned orbital transfer vehicle  

NASA Technical Reports Server (NTRS)

With the advent of the manned space station, man now requires a spacecraft based on the space station with the ability to deploy, recover, and repair satellites quickly and economically. Such a craft would prolong and enhance the life and performance of many satellites. A basic design was developed for an orbital tansfer vehicle (OTV). The basic design criteria are discussed. The design of the OTV and systems were researched in the following areas: avionics, crew systems, electrical power systems, environmental control/life support systems, navigation and orbital maneuvers, propulsion systems, reaction control systems (RCS), servicing systems, and structures. The basic concepts in each of the areas are summarized.

Davis, Richard; Duquette, Miles; Fredrick, Rebecca; Schumacher, Daniel; Somers, Schaeffer; Stafira, Stanley; Williams, James; Zelinka, Mark

1988-01-01

103

Pointing control design for autonomous space vehicle applications  

SciTech Connect

This paper addresses the design of pointing control systems for autonomous space vehicles. The function of the pointing control system is to keep distant orbiting objects within the field-of-view of an on-board optical sensor. We outline the development of novel nonlinear control algorithms which exploit the availability of on- board sensors. Simulation results comparing the performance of the different pointing control implementations are presented.

Young, K.D.

1993-03-01

104

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

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

105

Design of Energy Management Systems for Mobile Power Station of Electric Vehicles  

Microsoft Academic Search

The current development and situation of electric vehicle battery charging station are introduced and analyzed, and a design scheme of mobile power station for electric vehicles is presented. The mobile power station for electric vehicles in this scheme can directly get electricity to drive the electromotor from the electricity supply grid for electric vehicles or oil dual-mode electric drive motor-powered

Zhang Yu; Minghong Zhang; Jianning Yang

2009-01-01

106

NASA advanced aeronautics design solar powered remotely piloted vehicle  

NASA Technical Reports Server (NTRS)

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.

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

107

Design Guidelines for Quiet Fans and Pumps for Space Vehicles  

NASA Technical Reports Server (NTRS)

This document presents guidelines for the design of quiet fans and pumps of the class used on space vehicles. A simple procedure is presented for the prediction of fan noise over the meaningful frequency spectrum. A section also presents general design criteria for axial flow fans, squirrel cage fans, centrifugal fans, and centrifugal pumps. The basis for this report is an experimental program conducted by Hamilton Standard under NASA Contract NAS 9-12457. The derivations of the noise predicting methods used in this document are explained in Hamilton Standard Report SVHSER 6183, "Fan and Pump Noise Control," dated May 1973 (6).

Lovell, John S.; Magliozzi, Bernard

2008-01-01

108

Launch Vehicle Propulsion Design with Multiple Selection Criteria  

NASA Technical Reports Server (NTRS)

The approach and techniques described herein define an optimization and evaluation approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system. The method uses Monte Carlo simulations, genetic algorithm solvers, a propulsion thermo-chemical code, power series regression curves for historical data, and statistical models in order to optimize a vehicle system. The system, including parameters for engine chamber pressure, area ratio, and oxidizer/fuel ratio, was modeled and optimized to determine the best design for seven separate design weight and cost cases by varying design and technology parameters. Significant model results show that a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Other key findings show the sensitivity of propulsion parameters, technology factors, and cost factors and how these parameters differ when cost and weight are optimized separately. Each of the three key propulsion parameters; chamber pressure, area ratio, and oxidizer/fuel ratio, are optimized in the seven design cases and results are plotted to show impacts to engine mass and overall vehicle mass.

Shelton, Joey D.; Frederick, Robert A.; Wilhite, Alan W.

2005-01-01

109

Older Drivers Attitudes about Instrument Cluster Designs in Vehicles  

PubMed Central

Little is known about older drivers preferences and attitudes about instrumentation design in vehicles. Yet visual processing impairments are common among older adults and could impact their ability to interface with a vehicles dashboard. The purpose of this study is to obtain information from them about this topic, using focus groups and content analysis methodology. A trained facilitator led 8 focus groups of older adults. Discussion was stimulated by an outline relevant to dashboard interfaces, audiotaped, and transcribed. Using multi-step content analysis, a trained coder placed comments into thematic categories and coded comments as positive, negative, or neutral in meaning. Comments were coded into these categories: gauges, knobs/switches, interior lighting, color, lettering, symbols, location, entertainment, GPS, cost, uniformity, and getting information. Comments on gauges and knobs/switches represented half the comments. Women made more comments about getting information; men made more comments about uniformity. Positive and negative comments were made in each category; individual differences in preferences were broad. The results of this study will be used to guide the design of a population-based survey of older drivers about instrument cluster forma, which will also examine how their responses are related to their visual processing capabilities. PMID:21819831

Owsley, Cynthia; McGwin, Gerald; Seder, Thomas

2011-01-01

110

Design Considerations for Space Transfer Vehicles Using Solar Thermal Propulsion  

NASA Technical Reports Server (NTRS)

The economical deployment of satellites to high energy earth orbits is crucial to the ultimate success of this nations commerical space ventures and is highly desirable for deep space planetary missions requiring earth escape trajectories. Upper stage space transfer vehicles needed to accomplish this task should ideally be simple, robust, and highly efficient. In this regard, solar thermal propulsion is particularly well suited to those missions where high thrust is not a requirement. The Marshall Space Flight Center is , therefore, currently engaged in defining a transfer vehicle employing solar thermal propulsion capable of transferring a 1000 lb. payload from low Earth orbit (LEO) to a geostationary Earth orbit (GEO) using a Lockheed launch vehicle (LLV3) with three Castors and a large shroud. The current design uses liquid hydrogen as the propellant and employs two inflatable 16 x 24 feet eliptical off-axis parabolic solar collectors to focus sunlight onto a tungsten/rhenium windowless black body type absorber. The concentration factor on this design is projected to be approximately 1800:1 for the primary collector and 2.42:1 for the secondary collector for an overall concentration factor of nearly 4400:1. The engine, which is about twice as efficient as the best currently available chemical engines, produces two pounds of thrust with a specific impulse (Isp) of 860 sec. Transfer times to GEO are projected to be on the order of one month. The launch and deployed configurations of the solar thermal upper stage (STUS) are depicted.

Emrich, William J.

1995-01-01

111

Reentry Vehicle Flight Controls Design Guidelines: Dynamic Inversion  

NASA Technical Reports Server (NTRS)

This report addresses issues in developing a flight control design for vehicles operating across a broad flight regime and with highly nonlinear physical descriptions of motion. Specifically it addresses the need for reentry vehicles that could operate through reentry from space to controlled touchdown on Earth. The latter part of controlled descent is achieved by parachute or paraglider - or by all automatic or a human-controlled landing similar to that of the Orbiter. Since this report addresses the specific needs of human-carrying (not necessarily piloted) reentry vehicles, it deals with highly nonlinear equations of motion, and then-generated control systems must be robust across a very wide range of physics. Thus, this report deals almost exclusively with some form of dynamic inversion (DI). Two vital aspects of control theory - noninteracting control laws and the transformation of nonlinear systems into equivalent linear systems - are embodied in DI. Though there is no doubt that the mathematical tools and underlying theory are widely available, there are open issues as to the practicality of using DI as the only or primary design approach for reentry articles. This report provides a set of guidelines that can be used to determine the practical usefulness of the technique.

Ito, Daigoro; Georgie, Jennifer; Valasek, John; Ward, Donald T.

2002-01-01

112

Assured crew return vehicle post landing configuration design and test  

NASA Technical Reports Server (NTRS)

The 1991-1992 senior Mechanical and Aerospace Engineering Design class continued work on the post landing configurations for the Assured Crew Return Vehicle (ACRV) and the Emergency Egress Couch (EEC). The ACRV will be permanently docked to Space Station Freedom fulfilling NASA's commitment of Assured Crew Return Capability in the event of an accident or illness aboard Space Station Freedom. The EEC provides medical support and a transportation surface for an incapacitated crew member. The objective of the projects was to give the ACRV Project Office data to feed into their feasibility studies. Four design teams were given the task of developing models with dynamically and geometrically scaled characteristics. Groups one and two combined efforts to design a one-fifth scale model for the Apollo Command Module derivative, an on-board flotation system, and a lift attachment point system. This model was designed to test the feasibility of a rigid flotation and stabilization system and to determine the dynamics associated with lifting the vehicle during retrieval. However, due to priorities, it was not built. Group three designed a one-fifth scale model of the Johnson Space Center (JSC) benchmark configuration, the Station Crew Return Alternative Module (SCRAM) with a lift attachment point system. This model helped to determine the flotation and lifting characteristics of the SCRAM configuration. Group four designed a full scale EEC with changeable geometric and geometric and dynamic characteristics. This model provided data on the geometric characteristics of the EEC and on the placement of the CG and moment of inertia. It also gave the helicopter rescue personnel direct input to the feasibility study. Section 1 describes in detail the design of a one-fifth scale model of the Apollo Command Module Derivative (ACMD) ACRV. The objective of the ACMD Configuration Model Team was to use geometric and dynamic constraints to design a one-fifth scale working model of the Apollo Command Module Derivative (ACMD) configuration with a Lift Attachment Point (LAP) System. This model was required to incorporate a rigidly mounted flotation system and the egress system designed the previous academic year. The LAP system was to be used to determine the dynamic effects of locating the lifting points at different locations on the vehicle. The team was then to build and test the model; however, due to priorities, this did not occur. To better simulate the ACMD after a water landing, the nose cone section was removed and the deck area exposed. The areas researched during the design process were construction, center of gravity and moment of inertia, and lift attachment points.

1992-01-01

113

GPS Auto-Navigation Design for Unmanned Air Vehicles  

NASA Technical Reports Server (NTRS)

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

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

2003-01-01

114

SYSTEM DESIGN OF A VEHICLE STRUCTURE BY A NETWORK OF OPTIMIZATIONS  

Microsoft Academic Search

Vehicle design is a complex process requiring interactions and exchange of information among multiple disciplines such as fatigue, strength, propulsion, survivability, safety, thermal management, stealth, maintenance, and manufacturing. Simulation models are employed for assessing and potentially improving a vehicle's performance in individual technical areas. The vehicle's characteristics influence the performance in all the different attributes. Challenges arise when designing a

Jim He; Christopher G. Hart; Nickolas Vlahopoulos

115

Design, development, and validation of a remotely reconfigurable vehicle telemetry system for consumer and government applications  

E-print Network

This thesis explores the design and development of a cost-effective, easy-to-use system for remotely monitoring vehicle performance and drivers' habits, with the aim of collecting data for vehicle characterization and ...

Siegel, Joshua Eric

2011-01-01

116

Vehicle Design Validation via Remote Vehicle Diagnosis: A feasibility study on battery management system  

Microsoft Academic Search

In recent years, passenger vehicle product development faces great challenges to maintain high vehicle quality due to the proliferation of Electronics, Control and Software (ECS) features and the resultant system complexity. Quickly detecting and trouble-shooting faults of integrated vehicle systems during the validation stage in a key to enhancing vehicle quality. In this paper, we present a feasibilty study of

Yilu Zhang; Gary W. Gantt Jr; Mark Rychlinski; Ryan Edwards; John Correia; Calvin Wolf

2008-01-01

117

Video displays for tracked vehicle FLIR systems: some design considerations  

NASA Astrophysics Data System (ADS)

The thrust of this paper will be to trace some of the design decisions made during development of the M1A2 System Enhancement Package (SEP) Forward Looking Infrared (FLIR) display. We will describe factors which determined the size, resolution, optical filtering, as well as packaging characteristics. The Commanders Thermal Viewer (CTV) display is a 16:9 aspect ratio, 9.2' diagonal, mirror electrode EL, providing a 1316 X 480 pixel resolution. These characteristics were determined through a combination of vehicle space limitations, human factors considerations and technology limitations. Packaging, both electrical and mechanical were determined by the environmental and physical constraints of confined space inside a main battle tank.

Thomas, John T.; Downs, Greg

1999-08-01

118

Operational design factors for advanced space transportation vehicles  

NASA Astrophysics Data System (ADS)

The tools and techniques needed to provide design decision-makers with balanced quantitative assessments of the potential operability consequences of their decisions are addressed. The factors controlling operability are identified, and a methodology to predict the impact of these factors on a specific launch vehicle is developed. Requirements to control these factors are established, and analytical tools developed specifically for performing detailed simulations to verify specific operability characteristics are described. An approach to collect, store, organize, and access high-quality historical, current, and future launch system data for the benefit of the USAF and the U.S. launch system community at large is outlined.

Whitehair, C. L.; Hickman, R. A.; Adams, J. D.; Wolfe, M. G.

1992-08-01

119

Design and Control of a Fully Automated Vehicle door  

E-print Network

capacity of 20 pounds, which is sufficient force to motivate vehicle doors. A pulse width magnitude (PWM) signal generated by the PIC micro controller controls the velocity of the motor. In order to maintain the door at a constant angular velocity... door, actuator, sensors, PIC microcontroller, power supply and a mount. The design requirements for the test bed were that it be strong enough to support the weight of the door, have a stable base with a low center of gravity and be mobile...

Hong, Kyung-Min

2010-07-14

120

Assured crew return vehicle post landing configuration design and test  

NASA Technical Reports Server (NTRS)

The 1991-1992 senior Mechanical and Aerospace Engineering Design class continued work on the post landing configurations for the Assured Crew Return Vehicle (ACRV) and the Emergency Egress Couch (EEC). The ACRV will be permanently docked to Space Station Freedom, fulfilling NASA's commitment of Assured Crew Return Capability in the event of an accident or illness aboard Space Station Freedom. The EEC provides medical support and a transportation surface for an incapacitated crew member. The objective of the projects was to give the ACRV Project Office data to feed into their feasibility studies. Four design teams were given the task of developing models with dynamically and geometrically scaled characteristics. Groups one and two combined effort to design a one-fifth scale model of the Apollo Command Module derivative, an on-board flotation system, and a lift attachment point system. This model was designed to test the feasibility of a rigid flotation and stabilization system and to determine the dynamics associated with lifting the vehicle during retrieval. However, due to priorities, it was not built. Group three designed a one-fifth scale model of the Johnson Space Center (JSC) benchmark configuration, the Station Crew Return Alternative Module (SCRAM) with a lift attachment point system. This model helped to determine the flotation and lifting characteristics of the SCRAM configuration. Group four designed a full scale EEC with changeable geometric and dynamic characteristics. This model provided data on the geometric characteristics of the EEC and on the placement of the CG and moment of inertia. It also gave the helicopter rescue personnel direct input to the feasibility study.

Anderson, Loren A.; Armitage, Pamela Kay

1992-01-01

121

Computer Aided Design Tool for Electric, Hybrid Electric and Plug-in Hybrid Electric Vehicles  

E-print Network

This research is focused on designing a new generation of CAD tools that could help a hybrid vehicle designer with the design process to come up with better vehicle configurations. The conventional design process for any type of hybrid-electric...

Eskandari Halvaii, Ali

2012-07-16

122

Design and implementation of Lab. simulator for vehicle control  

Microsoft Academic Search

Lab. simulator for conducting a performance test and a reliability test on a vehicle and components has been embodied. In order to control non-linear of a vehicle, a fuzzy control algorithm, a running mode tracking algorithm and a vehicle speed control algorithm were applied to the actuator control. The vehicle controller and servo controller functions were implemented; position control, the

Jeongdai Jo; Heon Jeong; Kwang-Young Kim; Dong-Soo Kim; Do-Sik Kim

2007-01-01

123

Older drivers' attitudes about instrument cluster designs in vehicles.  

PubMed

Little is known about older drivers' preferences and attitudes about instrumentation design in vehicles. Yet visual processing impairments are common among older adults and could impact their ability to interface with a vehicle's dashboard. The purpose of this study is to obtain information from them about this topic, using focus groups and content analysis methodology. A trained facilitator led 8 focus groups of older adults. Discussion was stimulated by an outline relevant to dashboard interfaces, audiotaped, and transcribed. Using multi-step content analysis, a trained coder placed comments into thematic categories and coded comments as positive, negative, or neutral in meaning. Comments were coded into these categories: gauges, knobs/switches, interior lighting, color, lettering, symbols, location, entertainment, GPS, cost, uniformity, and getting information. Comments on gauges and knobs/switches represented half the comments. Women made more comments about getting information; men made more comments about uniformity. Positive and negative comments were made in each category; individual differences in preferences were broad. The results of this study will be used to guide the design of a population-based survey of older drivers about instrument cluster format, which will also examine how their responses are related to their visual processing capabilities. PMID:21819831

Owsley, Cynthia; McGwin, Gerald; Seder, Thomas

2011-11-01

124

Design of an interim space rescue ferry vehicle  

NASA Technical Reports Server (NTRS)

This paper proposes a stop-gap nonoptimum vehicle for transferring astronauts from a tumbling stranded spacecraft to a nearby rescue spacecraft. The design is limited to the use of available or 'soon-to-be' available flight-qualified hardware and consists of three major components: the manned maneuvering unit, the personnel rescue enclosure, and the apogee kick motor capture device. The apogee kick motor capture device is modified to serve as the connection between the manned maneuvering unit and the personnel rescue enclosure. The performance of this interim rescue vehicle is analyzed with NASA flight simulation software to test the feasibility of the design. Results show that the control system of the manned maneuvering unit adequately limits uncommanded rotations during all simulated maneuvers in the primary control mode but not during transverse translations in the backup control mode. Impingement of thruster plumes on the personnel rescue enclosure is shown to be of some importance in certain maneuvers. The satellite stabilization mode of the control system is found to have significant rotational-to-translational coupling that has associated adverse effects on flying qualities, making the mode undesirable for the rescue mission.

Halsell, James D., Jr.; Widhalm, Joseph W.; Whitsett, Charles E.

1988-01-01

125

Structural design and fabrication techniques of composite unmanned aerial vehicles  

NASA Astrophysics Data System (ADS)

Popularity of unmanned aerial vehicles has grown substantially in recent years both in the private sector, as well as for government functions. This growth can be attributed largely to the increased performance of the technology that controls these vehicles, as well as decreasing cost and size of this technology. What is sometimes forgotten though, is that the research and advancement of the airframes themselves are equally as important as what is done with them. With current computer-aided design programs, the limits of design optimization can be pushed further than ever before, resulting in lighter and faster airframes that can achieve longer endurances, higher altitudes, and more complex missions. However, realization of a paper design is still limited by the physical restrictions of the real world and the structural constraints associated with it. The purpose of this paper is to not only step through current design and manufacturing processes of composite UAVs at Oklahoma State University, but to also focus on composite spars, utilizing and relating both calculated and empirical data. Most of the experience gained for this thesis was from the Cessna Longitude project. The Longitude is a 1/8 scale, flying demonstrator Oklahoma State University constructed for Cessna. For the project, Cessna required dynamic flight data for their design process in order to make their 2017 release date. Oklahoma State University was privileged enough to assist Cessna with the mission of supporting the validation of design of their largest business jet to date. This paper will detail the steps of the fabrication process used in construction of the Longitude, as well as several other projects, beginning with structural design, machining, molding, skin layup, and ending with final assembly. Also, attention will be paid specifically towards spar design and testing in effort to ease the design phase. This document is intended to act not only as a further development of current practices, but also as a step-by-step manual for those who aspire to make composite airframes, predominantly the Oklahoma State University MAE students who either are, or will be using these techniques on a daily basis.

Hunt, Daniel Stephen

126

Optimal design of a magnetorheological fluid suspension for tracked vehicle  

NASA Astrophysics Data System (ADS)

This paper presents optimal design of controllable magnetorheological suspension system (MRSS) for a tracked vehicle. As a first step, a double-rod type MRSS is designed on the basis of the Bingham model of commercially available MR fluid, and its damping characteristics are evaluated with respect to the intensity of the magnetic field. Subsequently, the governing equation of motion of the MRSS featuring the MR valve is established Then, the optimization problem to find optimal geometric dimensions of the MRSS is formulated by considering an objective function which is related to damping torque and control energy. The first order optimization method intergrated with a commercial finite element method(FEM) software is adopted to obtain optimal solution of the system. The performance characteristics of the optimized MRSS are then evaluated and compared with initial ones.

Ha, S. H.; Choi, S. B.; Rhee, E. J.; Kang, P. S.

2009-02-01

127

Modeling of hybrid electric vehicles using gyrator theory: application to design  

Microsoft Academic Search

Modeling and design of advanced vehicles such as hybrid electric vehicles (HEV) and more electric cars (MEC) are challenging because of the presence of two power plants in the vehicle, i.e., an internal combustion engine (ICE) or a fuel cell and an electric power plant. For the modeling of such complex hybrid systems, the gyrator theory has many advantages. The

J. Y. Routex; S. Gay-Desharnais; M. Ehsani

2000-01-01

128

Topology, design, analysis and thermal management of power electronics for hybrid electric vehicle  

E-print Network

Topology, design, analysis and thermal management of power electronics for hybrid electric vehicle an important role in the success of electric, hybrid and fuel cell vehicles. Typical power electronics circuits in hybrid vehicles include electric motor drive circuits and DC/DC converter circuits. Conventional circuit

Mi, Chunting "Chris"

129

Design and Control of the Induction Motor Propulsion of an Electric Vehicle  

E-print Network

Design and Control of the Induction Motor Propulsion of an Electric Vehicle B. Tabbache1,2 , A for presizing the induction motor propulsion of an Electric Vehicle (EV). Based on the EV desired performances for different induction motor-based EVs using a siding mode control technique. Index Terms--Electric Vehicle (EV

Brest, Université de

130

Designing a Fuzzy Logic Controller to Enhance Directional Stability of Vehicles under Difficult Maneuvers  

Microsoft Academic Search

Vehicle which are turning or maneuvering at high speeds are susceptible to sliding and subsequently deviate from desired path. In this paper the dynamics governing the Yaw\\/Roll behavior of a vehicle has been simulated. Two different simulations have been used one for the real vehicle, for which a fuzzy controller is designed to increase its directional stability property. The other

Mehrdad N. Khajavi; Ali Hakima

131

Series hybrid vehicles and optimized hydrogen engine design  

SciTech Connect

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{sub 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{sub x} concentrations must be less than 180 ppm to meet the 0.2 g/mile California Air Resources Board ULEV or Federal Tier II 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.

Smith, J.R.; Aceves, S. [Lawrence Livermore National Lab., CA (United States); Van Blarigan, P. [Sandia National Labs., Livermore, CA (United States)

1995-05-10

132

Series hybrid vehicles and optimized hydrogen engine design  

NASA Astrophysics Data System (ADS)

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.

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

1995-05-01

133

Design Study of Wafer Seals for Future Hypersonic Vehicles  

NASA Technical Reports Server (NTRS)

Future hypersonic vehicles require high temperature, dynamic seals in advanced hypersonic engines and on the vehicle airframe to seal the perimeters of movable panels, flaps, and doors. Current seals do not meet the demanding requirements of these applications, so NASA Glenn Research Center is developing improved designs to overcome these shortfalls. An advanced ceramic wafer seal design has shown promise in meeting these needs. Results from a design of experiments study performed on this seal revealed that several installation variables played a role in determining the amount of leakage past the seals. Lower leakage rates were achieved by using a tighter groove width around the seals, a higher seal preload, a tighter wafer height tolerance, and a looser groove length. During flow testing, a seal activating pressure acting behind the wafers combined with simulated vibrations to seat the seals more effectively against the sealing surface and produce lower leakage rates. A seal geometry study revealed comparable leakage for full-scale wafers with 0.125 and 0.25 in. thicknesses. For applications in which lower part counts are desired, fewer 0.25-in.-thick wafers may be able to be used in place of 0.125-in.-thick wafers while achieving similar performance. Tests performed on wafers with a rounded edge (0.5 in. radius) in contact with the sealing surface resulted in flow rates twice as high as those for wafers with a flat edge. Half-size wafers had leakage rates approximately three times higher than those for full-size wafers.

Dunlap, Patrick H.; Finkbeiner, Joshua R.; Steinetz, Bruce M.; DeMange, Jeffrey J.

2005-01-01

134

Coupled Vehicle Design and Network Flow Optimization for Air Transportation Systems  

E-print Network

Coupled Vehicle Design and Network Flow Optimization for Air Transportation Systems Christine: 10.2514/1.27320 Traditionally, the design of a transportation system has focused on either vehicle for a transportation system, it is advantageous to expand the system boundary during the design process to include

de Weck, Olivier L.

135

Crew Exploration Vehicle Environmental Control and Life Support Design Reference Missions  

NASA Technical Reports Server (NTRS)

In preparation for the contract award of the Crew Exploration Vehicle (CEV), the National Aeronautics and Space Administration (NASA) produced two design reference missions for the vehicle. The design references used teams of engineers across the agency to come up with two configurations. This process helped NASA understand the conflicts and limitations in the CEV design, and investigate options to solve them.

Lewis, John F.; Anderson, Molly K.; Ewert, Mike S.; Stephan, Ryan A.; Carrasquillo, Robyn L.

2007-01-01

136

The computational design of a water jet propulsion spherical underwater vehicle  

Microsoft Academic Search

Underwater vehicles have become an important tool to develop oceans. The design of the shape, hardware circuit and software of a water jet propulsion spherical underwater vehicle was introduced, and the characteristics of water jet pump were presented. The design of the thruster and computation of the thrust was proposed, too. A desired movement result was achieved by the designed

Shuxiang Guo; Juan Du; Xiufen Ye; Rui Yan; Hongtao Gao

2011-01-01

137

THE DEFINITION AND INTERPRETATION OF TERRESTRIAL ENVIRONMENT DESIGN INPUTS FOR VEHICLE DESIGN CONSIDERATIONS  

NASA Technical Reports Server (NTRS)

The description and interpretation of the terrestrial environment (0-90 km altitude) is an important driver of aerospace vehicle structural, control, and thermal system design. NASA is currently in the process of reviewing the meteorological information acquired over the past decade and producing an update to the 1993 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, sea state, etc. In addition, the respective engineering design elements will be discussed relative to the importance and influence of terrestrial environment inputs that require consideration and interpretation for design applications. Specific lessons learned that have contributed to the advancements made in the acquisition, interpretation, application and awareness of terrestrial environment inputs for aerospace engineering applications are discussed.

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

2005-01-01

138

Design of a Vehicle Based Intervention System to Prevent Ozone Loss  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

139

that minimizes vehicle emissions during design of routes in congested environments with time-dependent travel speeds, hard time windows,  

E-print Network

that minimizes vehicle emissions during design of routes in congested environments with time-dependent travel speeds, hard time windows, andcapacityconstraints.ThiscreatesanewtypeofVRP,theemissions vehicle routing problem (EVRP). BACKGROUND AND LITERATURE REVIEW There is extensive literature related to vehicle

Bertini, Robert L.

140

Man-Vehicle Systems Research Facility - Design and operating characteristics  

NASA Technical Reports Server (NTRS)

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.

Shiner, Robert J.; Sullivan, Barry T.

1992-01-01

141

Aerothermodynamic design feasibility of a Mars aerocapture/aeromaneuver vehicle  

NASA Technical Reports Server (NTRS)

Lifting aerodynamic configurations have been screened and selected for the Mars aerocapture mission that (1) meet the geometric packaging requirements of the various payloads and the Space Shuttle cargo bay and (2) provide the aerodynamic performance characteristics required to obtain the atmospheric exit steering accuracy and the parachute deployment conditions desired. Hypersonic heat transfer and aerodynamic loads to the vehicle in the CO2 atmosphere are evaluated. Contemporary low density ablative thermal protection materials were selected that meet all the atmospheric entry requirements and provide a minimum mass solution. Results are presented of the aerodynamic configuration and thermal protection materials screening and selection. It is concluded that the aerothermodynamic design of this concept is feasible using state-of-the-art technology.

Florence, D. E.

1981-01-01

142

Hybrid Wing Body Planform Design with Vehicle Sketch Pad  

NASA Technical Reports Server (NTRS)

The objective of this paper was to provide an update on NASA s current tools for design and analysis of hybrid wing body (HWB) aircraft with an emphasis on Vehicle Sketch Pad (VSP). NASA started HWB analysis using the Flight Optimization System (FLOPS). That capability is enhanced using Phoenix Integration's ModelCenter(Registered TradeMark). Model Center enables multifidelity analysis tools to be linked as an integrated structure. Two major components are linked to FLOPS as an example; a planform discretization tool and VSP. The planform discretization tool ensures the planform is smooth and continuous. VSP is used to display the output geometry. This example shows that a smooth & continuous HWB planform can be displayed as a three-dimensional model and rapidly sized and analyzed.

Wells, Douglas P.; Olson, Erik D.

2011-01-01

143

Optimization of Turbine Blade Design for Reusable Launch Vehicles  

NASA Technical Reports Server (NTRS)

To facilitate design optimization of turbine blade shape for reusable launching vehicles, appropriate techniques need to be developed to process and estimate the characteristics of the design variables and the response of the output with respect to the variations of the design variables. The purpose of this report is to offer insight into developing appropriate techniques for supporting such design and optimization needs. Neural network and polynomial-based techniques are applied to process aerodynamic data obtained from computational simulations for flows around a two-dimensional airfoil and a generic three- dimensional wing/blade. For the two-dimensional airfoil, a two-layered radial-basis network is designed and trained. The performances of two different design functions for radial-basis networks, one based on the accuracy requirement, whereas the other one based on the limit on the network size. While the number of neurons needed to satisfactorily reproduce the information depends on the size of the data, the neural network technique is shown to be more accurate for large data set (up to 765 simulations have been used) than the polynomial-based response surface method. For the three-dimensional wing/blade case, smaller aerodynamic data sets (between 9 to 25 simulations) are considered, and both the neural network and the polynomial-based response surface techniques improve their performance as the data size increases. It is found while the relative performance of two different network types, a radial-basis network and a back-propagation network, depends on the number of input data, the number of iterations required for radial-basis network is less than that for the back-propagation network.

Shyy, Wei

1998-01-01

144

The ironies of vehicle feedback in car design  

Microsoft Academic Search

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 195354). The irony is that this level of sensitivity stands in contrast to the significant changes in vehicle feel accompanying

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

2006-01-01

145

The Household Market for Electric Vehicles: Testing the Hybrid Household Hypothesis--A Reflively Designed Survey of New-car-buying, Multi-vehicle California Households  

E-print Network

ELECTRIC VEHICLES How many hybrid households are in the California new carElectric Vehicles: Testing the Hybrid Household Hypothesis - A Reflively Designed Survey of New-car-Electric Vehicles: Testing the Hybrid Household Hypothesis A Reflexively Designed Survey of New-car-

Turrentine, Thomas; Kurani, Kenneth

1995-01-01

146

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

NASA Technical Reports Server (NTRS)

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.

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

147

Launch vehicle propulsion parameter design multiple selection criteria  

NASA Astrophysics Data System (ADS)

The optimization tool described herein addresses and emphasizes the use of computer tools to model a system and focuses on a concept development approach for a liquid hydrogen/liquid oxygen single-stage-to-orbit system, but more particularly the development of the optimized system using new techniques. This methodology uses new and innovative tools to run Monte Carlo simulations, genetic algorithm solvers, and statistical models in order to optimize a design concept. The concept launch vehicle and propulsion system were modeled and optimized to determine the best design for weight and cost by varying design and technology parameters. Uncertainty levels were applied using Monte Carlo Simulations and the model output was compared to the National Aeronautics and Space Administration Space Shuttle Main Engine. Several key conclusions are summarized here for the model results. First, the Gross Liftoff Weight and Dry Weight were 67% higher for the design case for minimization of Design, Development, Test and Evaluation cost when compared to the weights determined by the minimization of Gross Liftoff Weight case. In turn, the Design, Development, Test and Evaluation cost was 53% higher for optimized Gross Liftoff Weight case when compared to the cost determined by case for minimization of Design, Development, Test and Evaluation cost. Therefore, a 53% increase in Design, Development, Test and Evaluation cost results in a 67% reduction in Gross Liftoff Weight. Secondly, the tool outputs define the sensitivity of propulsion parameters, technology and cost factors and how these parameters differ when cost and weight are optimized separately. A key finding was that for a Space Shuttle Main Engine thrust level the oxidizer/fuel ratio of 6.6 resulted in the lowest Gross Liftoff Weight rather than at 5.2 for the maximum specific impulse, demonstrating the relationships between specific impulse, engine weight, tank volume and tank weight. Lastly, the optimum chamber pressure for Gross Liftoff Weight minimization was 2713 pounds per square inch as compared to 3162 for the Design, Development, Test and Evaluation cost optimization case. This chamber pressure range is close to 3000 pounds per square inch for the Space Shuttle Main Engine.

Shelton, Joey Dewayne

148

Unmanned, space-based, reusable orbital transfer vehicle, DARVES. Volume 1: Trade analysis and design  

NASA Technical Reports Server (NTRS)

The design of an unmanned, space-based, reusable Orbital Transfer Vehicle (OTV) is presented. This OTV will be utilized for the delivery and retrieval of satellites from geosynchronous Earth orbit (GEO) in conjunction with a space station assumed to be in existence in low Earth orbit (LEO). The trade analysis used to determine the vehicle design is presented, and from this study a vehicle definition is given.

1988-01-01

149

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars are reported. Problem areas include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis, terrain modeling and path selection; and chemical analysis of specimens. These tasks are summarized: vehicle model design, mathematical model of vehicle dynamics, experimental vehicle dynamics, obstacle negotiation, electrochemical controls, remote control, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, and chromatograph model evaluation and improvement.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. V.; Yerazunis, S. W.

1973-01-01

150

Analysis and design of a capsule landing system and surface vehicle control system for Mars exporation  

NASA Technical Reports Server (NTRS)

The problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars were investigated. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; navigation, terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks were studied: vehicle model design, mathematical modeling of dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer subsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement and transport parameter evaluation.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

151

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Investigation of problems related to the design and control of a mobile planetary vehicle to implement a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: vehicle configuration, control, dynamics, systems and propulsion; systems analysis; terrain modeling and path selection; and chemical analysis of specimens. The following specific tasks have been under study: vehicle model design, mathematical modeling of a dynamic vehicle, experimental vehicle dynamics, obstacle negotiation, electromechanical controls, collapsibility and deployment, construction of a wheel tester, wheel analysis, payload design, system design optimization, effect of design assumptions, accessory optimal design, on-board computer sybsystem, laser range measurement, discrete obstacle detection, obstacle detection systems, terrain modeling, path selection system simulation and evaluation, gas chromatograph/mass spectrometer system concepts, chromatograph model evaluation and improvement.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1972-01-01

152

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

The following tasks related to the design, construction, and evaluation of a mobile planetary vehicle for unmanned exploration of Mars are discussed: (1) design and construction of a 0.5 scale dynamic vehicle; (2) mathematical modeling of vehicle dynamics; (3) experimental 0.4 scale vehicle dynamics measurements and interpretation; (4) vehicle electro-mechanical control systems; (5) remote control systems; (6) collapsibility and deployment concepts and hardware; (7) design, construction and evaluation of a wheel with increased lateral stiffness, (8) system design optimization; (9) design of an on-board computer; (10) design and construction of a laser range finder; (11) measurement of reflectivity of terrain surfaces; (12) obstacle perception by edge detection; (13) terrain modeling based on gradients; (14) laser scan systems; (15) path selection system simulation and evaluation; (16) gas chromatograph system concepts; (17) experimental chromatograph separation measurements and chromatograph model improvement and evaluation.

Frederick, D. K.; Lashmet, P. K.; Moyer, W. R.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1973-01-01

153

The Effect of Predicted Vehicle Displacement on Ground Crew Task Performance and Hardware Design  

NASA Technical Reports Server (NTRS)

NASA continues to explore new launch vehicle concepts that will carry astronauts to low- Earth orbit to replace the soon-to-be retired Space Transportation System (STS) shuttle. A tall vertically stacked launch vehicle (> or =300 ft) is exposed to the natural environment while positioned on the launch pad. Varying directional winds and vortex shedding cause the vehicle to sway in an oscillating motion. Ground crews working high on the tower and inside the vehicle during launch preparations will be subjected to this motion while conducting critical closeout tasks such as mating fluid and electrical connectors and carrying heavy objects. NASA has not experienced performing these tasks in such environments since the Saturn V, which was serviced from a movable (but rigid) service structure; commercial launchers are likewise attended by a service structure that moves away from the vehicle for launch. There is concern that vehicle displacement may hinder ground crew operations, impact the ground system designs, and ultimately affect launch availability. The vehicle sway assessment objective is to replicate predicted frequencies and displacements of these tall vehicles, examine typical ground crew tasks, and provide insight into potential vehicle design considerations and ground crew performance guidelines. This paper outlines the methodology, configurations, and motion testing performed while conducting the vehicle displacement assessment that will be used as a Technical Memorandum for future vertically stacked vehicle designs.

Atencio, Laura Ashley; Reynolds, David W.

2011-01-01

154

Estimating Basic Preliminary Design Performances of Aerospace Vehicles  

NASA Technical Reports Server (NTRS)

Aerodynamics and Performance Estimation Toolset is a collection of four software programs for rapidly estimating the preliminary design performance of aerospace vehicles represented by doing simplified calculations based on ballistic trajectories, the ideal rocket equation, and supersonic wedges through standard atmosphere. The program consists of a set of Microsoft Excel worksheet subprograms. The input and output data are presented in a user-friendly format, and calculations are performed rapidly enough that the user can iterate among different trajectories and/or shapes to perform "what-if" studies. Estimates that can be computed by these programs include: 1. Ballistic trajectories as a function of departure angles, initial velocities, initial positions, and target altitudes; assuming point masses and no atmosphere. The program plots the trajectory in two-dimensions and outputs the position, pitch, and velocity along the trajectory. 2. The "Rocket Equation" program calculates and plots the trade space for a vehicle s propellant mass fraction over a range of specific impulse and mission velocity values, propellant mass fractions as functions of specific impulses and velocities. 3. "Standard Atmosphere" will estimate the temperature, speed of sound, pressure, and air density as a function of altitude in a standard atmosphere, properties of a standard atmosphere as functions of altitude. 4. "Supersonic Wedges" will calculate the free-stream, normal-shock, oblique-shock, and isentropic flow properties for a wedge-shaped body flying supersonically through a standard atmosphere. It will also calculate the maximum angle for which a shock remains attached, and the minimum Mach number for which a shock becomes attached, all as functions of the wedge angle, altitude, and Mach number.

Luz, Paul L.; Alexander, Reginald

2004-01-01

155

High Efficiency Energy Storage System Design for Hybrid Electric Vehicle with Motor Drive Integration  

Microsoft Academic Search

This paper proposes a new energy storage system (ESS) design including both batteries and ultracapacitors (UC) in hybrid electric vehicle (HEV) and electric vehicle (EV) applications. The conventional designs require a dc-dc converter to interface the UC unit. Herein, the UC can be directly switched across the motor drive dc-link during the peak power demands. The resulting wide voltage variation

Shuai Lu; Keith A. Corzine; Mehdi Ferdowsi

2006-01-01

156

Adjoint-Based Aerothermodynamic Shape Design of Hypersonic Vehicles in Non-Equilibrium Flows  

E-print Network

. The hypersonic vehicle design process requires the synthesis of aerothermodynamic, structural, TPS materialAdjoint-Based Aerothermodynamic Shape Design of Hypersonic Vehicles in Non-Equilibrium Flows Sean R geometries with aerothermodynamic considerations in the presence of high-enthalpy, chemically reactive gas

Alonso, Juan J.

157

Design of an agile unmanned combat vehicle: a product of the DARPA UGCV program  

Microsoft Academic Search

The unmanned ground compat vehicle (UGCV) design evolved by the SAIC team on the DARPA UGCV Program is summarized in this paper. This UGCV design provides exceptional performance against all of the program metrics and incorporates key attributes essential for high performance robotic combat vehicles. This performance includes protection against 7.62 mm threats, C130 and CH47 transportability, and the ability

Lindsey D. Thornhill; Alan Walls; Ronald C. Arkin; Joseph H. Beno; Chuck Bergh; Don Bresie; Anthony Giovannetti; Benny M. Gothard; Larry H. Matthies; Porfirio Nogueiro; Jim Scanlon; Ron Scott; Miguel Simon; Wilford Smith; Kenneth J. Waldron

2003-01-01

158

Deterministic Reconfigurable Control Design for the X-33 Vehicle  

NASA Technical Reports Server (NTRS)

In the event of a control surface failure, the purpose of a reconfigurable control system is to redistribute the control effort among the remaining working surfaces such that satisfactory stability and performance are retained. Four reconfigurable control design methods were investigated for the X-33 vehicle: Redistributed Pseudo-Inverse, General Constrained Optimization, Automated Failure Dependent Gain Schedule, and an Off-line Nonlinear General Constrained Optimization. The Off-line Nonlinear General Constrained Optimization approach was chosen for implementation on the X-33. Two example failures are shown, a right outboard elevon jam at 25 deg. at a Mach 3 entry condition, and a left rudder jam at 30 degrees. Note however, that reconfigurable control laws have been designed for the entire flight envelope. Comparisons between responses with the nominal controller and reconfigurable controllers show the benefits of reconfiguration. Single jam aerosurface failures were considered, and failure detection and identification is considered accomplished in the actuator controller. The X-33 flight control system will incorporate reconfigurable flight control in the baseline system.

Wagner, Elaine A.; Burken, John J.; Hanson, Curtis E.; Wohletz, Jerry M.

1998-01-01

159

Adjustment of Design Limited Imperfections for Transportation Vehicles  

NASA Astrophysics Data System (ADS)

The realization of light weight-construction without loss of passive safety in transportation vehicles is a big challenge for the next years. Considering the requirements on an automobile from consumer view a modern car should combine a high quality of comfort and standard with low operating expenses and a high safety standard. The use of lightweight design enables reductions in fuel consumption and CO2 emissions which are leading to a decrease of operating costs. The increase in passive safety is mainly characterized by an increase in strength and weight due to a concerted material selection, an enhancement of sheet metal thickness and additional compensating elements, e.g. patches. Especially for limited imperfections like cataphoretic drain holes or accesses for joining operations the strength adjustment without additional compensating elements and increasing weight possesses very much potential. The presented research investigate the possibility to reinforce local imperfections considering the material TRIP780 by combining different approaches on light-weight design. The reinforcements are realized by additional forming elements and enhance the moment of inertia. Different investigations were carried out to assess the placement and arrangement of the reinforcements in the deep drawing parts

Voges-Schwieger, Kathrin; Hbner, Sven; Behrens, Bernd-Arno

2011-05-01

160

Critical engine system design characteristics for SSTO vehicles  

NASA Astrophysics Data System (ADS)

Engine system design characteristics are summarized for typical vertical take-off and landing (VTOL) and vertical take-off and horizontal landing (VTHL) Strategic Defense Initiative Organization (SDIO) single stage to orbit (SSTO) vehicles utilizing plug nozzle configurations. Power cycle selection trades involved the unique modular platelet engine (MPE) with the use of (1) LO2 and LH2 at fixed and variable mixture ratios, (2) LO2 and propane or RP-1, and (3) dual fuels (LO2 with LH2 and C3H8). The number of thrust cells and modules were optimized. Dual chamber bell and a cluster of conventional bell nozzle configurations were examined for comparison with the plug configuration. Thrust modulation (throttling) was selected for thrust vector control. Installed thrust ratings were established to provide an additional 20 percent overthrust capability for engine out operation. Turbopumps were designed to operate at subcritical speeds to facilitate a wide range of throttling and long life. A unique dual spool arrangement with hydrostatic bearings was selected for the LH2 turbopump. Controls and health monitoring with expert systems for diagnostics are critical subsystems to ensure minimum maintenance and supportability for a less than seven day turnaround. The use of an idle mode start, in conjunction with automated health condition monitoring, allows the rocket propulsion system to operate reliably in the manner of present day aircraft propulsion.

Fanciullo, Thomas J.; Judd, D. C.; Obrien, C. J.

1992-02-01

161

Design and analysis of the front suspension geometry and steering system for a solar electric vehicle  

E-print Network

A study on the design of the front suspension geometry and steering system to be used in a solar electric vehicle. The suspension geometry utilizes a double wishbone design that is optimized to fit in the space constraints ...

Arensen, Bruce (Bruce Edward)

2014-01-01

162

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

NASA Technical Reports Server (NTRS)

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.

1989-01-01

163

Aerospace Vehicle Design, Spacecraft Section. Final Project Reports. Volume 2; Project Groups 6-8  

NASA Technical Reports Server (NTRS)

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 Freedam and provide 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 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. Special attention is given to spacecraft communications.

1989-01-01

164

System Design of Real Time Vehicle Type Recognition Based on Video for Windows (AVI) Files  

NASA Astrophysics Data System (ADS)

In this system, with technology of motion detection, the data frames include vehicle digital image can be detected automatically from a Video for Windows (AVI) File, at the same time, vehicle type will be recognized and displayed automatically. The system's process consists of five steps: Read the AVI file and decompose it into digital image frames; Motion detection; Vehicle digital image processing; Counting number of black pixels included in vehicle body contour and project on car image; Module of vehicle type classification. In particular, algorithm of vehicle recognition through counting number of black pixels included in vehicle body contour is one innovation algorithm. Experiment on actual AVI files shows: the system design is simple and effective.

Zhan, Wei; Luo, Zhiqing

165

System design and development of hybrid electric vehicles  

Microsoft Academic Search

Hybrid electric vehicles (HEVs) powered by electric machines and an internal combustion engine (ICE) are a promising means of reducing emissions and fuel consumption without compromising vehicle functionality and driving performance. Reducing emissions is important because pollution in cities is almost entirely due to transport and is linked to the illness and death of many people. This paper describes the

B. A. Kalan; H. C. Lovatt; M. Brothers; V. Buriak

2002-01-01

166

Design Criteria for Low Risk Re-Entry Vehicles  

Microsoft Academic Search

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

R. Monti; G. Pezzella

2005-01-01

167

Design of an autonomous underwater vehicle to evaluate the blazed array sonar and simultaneous localization and mapping algorithms  

E-print Network

This thesis has investigated aspects of the design of a new highly maneuverable Autonomous Underwater Vehicle - the XAUV. The overall goal for the design of this vehicle is to create a small, highly maneuverable AUV that ...

Uhle, Matthew William

2007-01-01

168

Hybrid vehicle system studies and optimized hydrogen engine design  

SciTech Connect

We have done system studies of series hydrogen 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. We have evaluated the impact of various on-board storage options on fuel economy. Experiments in an available engine at the Sandia CRF demonstrated NO{sub 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 simulation studies indicate that exhaust NO{sub x} concentrations must be less than 180 ppM to meet the 0.2 g/mile ULEV or Federal Tier II emissions regulations. LLNL has designed and fabricated a first generation optimized hydrogen engine head for use on an existing Onan engine. This head features 15:1 compression ratio, dual ignition, water cooling, two valves and open quiescent combustion chamber to minimize heat transfer losses. Initial testing shows promise of achieving an indicated efficiency of nearly 50% and emissions of less than 100 ppM NO{sub x}. Hydrocarbons and CO are to be measured, but are expected to be very low since their only source is engine lubricating oil. A successful friction reduction program on the Onan engine should result in a brake thermal efficiency of about 42% compared to today`s gasoline engines of 32%. Based on system studies requirements, the next generation engine will be about 2 liter displacement and is projected to achieve 46% brake thermal efficiency with outputs of 15 kW for cruise and 40 kW for hill climb.

Smith, J.R.; Aceves, S.

1995-04-26

169

Design and realization of an intelligent ground vehicle with modular payloads  

NASA Astrophysics Data System (ADS)

In June 2011, Worcester Polytechnic Institute's (WPI) unmanned ground vehicle Prometheus participated in the 8th Annual Robotic Lawnmower and 19th Annual Intelligent Ground Vehicle Competitions back-to-back. This paper details the two-year design and development cycle for WPI's intelligent ground vehicle, Prometheus. The on-board intelligence algorithms include lane detection, obstacle avoidance, path planning, world representation and waypoint navigation. The authors present experimental results and discuss practical implementations of the intelligence algorithms used on the robot.

Akmanalp, Mehmet A.; Doherty, Ryan M.; Gorges, Jeffrey; Kalauskas, Peter; Peterson, Ellen; Polido, Felipe; Nestinger, Stephen S.; Padir, Taskin

2012-01-01

170

Integrating Human Factors into Crew Exploration Vehicle Design  

NASA Technical Reports Server (NTRS)

With NASA's new Vision for Exploration to send humans beyond Earth orbit, it is critical to consider the human as a system that demands early and continuous user involvement, and an iterative prototype/test/redesign process. Addressing human-system interface issues early on can be very cost effective even cost reducing when performed early in the design and development cycle. To achieve this goal within Crew Exploration Vehicle (CEV) Project Office, human engineering (HE) team is formed. Key tasks are to apply HE requirements and guidelines to hardware/software, and provide HE design, analysis and evaluation of crew interfaces. Initial activities included many practice-orientated evaluations using low-fidelity CEV mock-ups. What follows is a description of such evaluations that focused on a HE requirement regarding Net Habitable Volume (NHV). NHV is defined as the total remaining pressurized volume available to on-orbit crew after accounting for the loss of volume due to deployed hardware and structural inefficiencies which decrease functional volume. The goal of the NHV evaluations was to develop requirements providing sufficient CEV NHV for crewmembers to live and perform tasks in support of mission goals. Efforts included development of a standard NHV calculation method using computer models and physical mockups, and crew/ stakeholder evaluations. Nine stakeholders and ten crewmembers participated in the unsuited evaluations. Six crewmembers also participated in a suited evaluation. The mock-up was outfitted with volumetric representation of sub-systems such as seats, and stowage bags. Thirteen scenarios were developed to represent mission/crew tasks and considered to be primary volume drivers (e.g., suit donning) for the CEV. Unsuited evaluations included a structured walkthrough of these tasks. Suited evaluations included timed donning of the existing launch and entry suit to simulate a contingency scenario followed by doffing/ stowing of the suits. All mockup evaluations were videotaped. Structured questionnaires were used to document user interface issues and volume impacts of layout configuration. Computer model and physical measures of the NHV agreed within 1 percent. This included measurement of the gross habitable volume, subtraction of intrusive volumes, and other non-habitable spaces. Calculation method developed was validated as a standard means of measuring NHV, and was recommended as a verification method for the NHV requirements. Evaluations confirmed that there was adequate volume for unsuited scenarios and suit donning/ doffing activity. Seats, suit design stowage and waste hygiene system noted to be critical volume drivers. The low-fidelity mock-up evaluations along with human modeling analysis generated discussions that will lead to high-level systems requirements and human-centered design decisions. This approach allowed HE requirements and operational concepts to evolve in parallel with engineering system concepts and design requirements. As the CEV design matures, these evaluations will continue and help with design decisions, and assessment, verification and validation of HE requirements.

Whitmore, Mihriban; Baggerman, Susan; Campbell, paul

2007-01-01

171

Effects of relaxed static longitudinal stability on a single-stage-to-orbit vehicle design  

NASA Technical Reports Server (NTRS)

The effects of relaxing longitudinal stability requirements on single stage to orbit space vehicles is studied. A comparison of the mass and performance characteristics of two vehicles, one designed for positive levels of longitudinal stability and the other designed with relaxed stability requirements in a computer aided design process is presented. Both vehicles, required to meet the same mission characteristics are described. Wind tunnel tests, conducted over a Mach number range from 0.3 to 4.63 to verify estimated aerodynamic characteristics, are discussed.

Freeman, D. C., Jr.; Wilhite, A. W.

1979-01-01

172

Design and realization of expressway vehicle path recognition and ETC system based on RFID  

Microsoft Academic Search

With the development of expressway, the vehicle path recognition based on RFID is designed and an Electronic Toll Collection system of expressway will be implemented. It uses a passive RFID tag as carrier to identify Actual vehicle path in loop road. The ETC system will toll collection without parking, also census traffic flow and audit road maintenance fees. It is

Zhihui Feng; Yanjie Zhu; Pengtao Xue; Mingjie Li

2010-01-01

173

A design of bi-verification vehicle access intelligent control system based on RFID  

Microsoft Academic Search

Radio-frequency identification (RFID) technology is widespread developed and common for vehicle management in intelligent community. However, smart card used as the sole certificate of identification could also be impersonated by criminals when the card is lost or stolen. In this paper, an improvement design to the current widely-used vehicle monitoring systems, which utilize the RFID technology to carry on is

Xiaohu Fan; Yulin Zhang

2009-01-01

174

Optimal Design of Power-Split Transmissions for Hydraulic Hybrid Passenger Vehicles  

E-print Network

Optimal Design of Power-Split Transmissions for Hydraulic Hybrid Passenger Vehicles Kai Loon Cheong, Perry Y. Li and Thomas R. Chase Abstract-- Hydraulic hybrid vehicles are inherently power dense. Power-split or hydro-mechanical transmissions (HMT) have advantages over series and parallel architectures

Li, Perry Y.

175

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

A number of problems related to the design, construction and evaluation of an autonomous roving planetary vehicle and its control and operating systems intended for an unmanned exploration of Mars are studied. Vehicle configuration, dynamics, control, systems and propulsion; systems analysis; terrain sensing and modeling and path selection; and chemical analysis of samples are included.

1974-01-01

176

Trajectory Design for Autonomous Underwater Vehicles based on Ocean Model Predictions for  

E-print Network

Trajectory Design for Autonomous Underwater Vehicles based on Ocean Model Predictions for Feature to the oceanographic research community. Intelligent planning is required to maneuver a vehicle to high-valued locations for data collection. We con- sider the use of ocean model predictions to determine the locations

Sukhatme, Gaurav S.

177

A realistic simulator for the design and evaluation of intelligent vehicles  

Microsoft Academic Search

The number of vehicles hitting the road each day is rapidly increasing, and several problems, such as traffic congestion or driver safety, can no longer be solved in the same fashion as before. Intelligent transportation systems could potentially solve part of these problems, but prototyping, designing and testing cooperative smart vehicles is a cumbersome task. This paper presents a realistic

Sven Gowal; Yizhen Zhang; Alcherio Martinoli

2010-01-01

178

AIAA engine design competition for a transatmospheric cargo (TAC) vehicle  

Microsoft Academic Search

Past studies of air-breathing\\/rocket single-stage-to-orbit vehicles are used here to develop approximate values for structural weight fraction and subsystem weight fraction for a typical transatmospheric cargo vehicle which could transport 2000 lb of personnel and provisions on a frequent basis to the Space Station Freedom. The studies have shown that structural weight fraction should be about 20 percent, and that

R. D. Kissinger; D. L. Kors

1990-01-01

179

Visualization of ground target designation from an unmanned aerial vehicle  

NASA Astrophysics Data System (ADS)

The common ground station (CGS) receives data from the joint surveillance and target attack radar system aircraft and from other airborne platforms. High-resolution imagery such as that provided by an unmanned airborne vehicle (UAV) carrying an IR and/or synthetic aperture radar (SAR) sensor will be incorporated into an advanced imagery CGS operation. While this level of integration provides a wealth of valuable information, it also increase the complexity of planning, assessment and exploitation which in turn dictates flexible simulation tools for mission rehearsal and operator training. MITRE has developed a ModSAF-driven model for a UAV equipped with a moving target indicator (MTI) radar for wide-area surveillance, and a battlefield combat identification system for positive identification of friendly forces. The imaging functions are performed by integrating the UAV model with visualization software in order to render the sensor's view in real-time. This model forms the basis for a multisensor CGS simulation controls imaging task assignments which taken place when an MTI track is selected for imaging by means of a mouse click entry on an active MTI display. At that time, the UAV is commanded to fly an automatically determined trajectory in order to align MTI display. At that time, the UAV is commanded to fly an automatically determined trajectory in order to align itself for the imaging task. A beam footprint whose position, size and shape is determined by the sensor position, attitude, and field-of-view appears on the display as an indication of the relationship of the image display to the terrain in the operational scenario. A 3D visualization of the designated target area then takes place on a separate display.

Violette Pierce, Deborah J.; Santapietro, John J.

1998-08-01

180

Visualization of ground target designation from an unmanned aerial vehicle  

E-print Network

The Common Ground Station (CGS) receives data from the Joint Surveillance and Target Attack Radar System (Joint STARS) aircraft and from other airborne platforms. High-resolution imagery such as that provided by an unmanned airborne vehicle (UAV) carrying an infrared (IR) and/or synthetic aperture radar (SAR) sensor will be incorporated into an Advanced Imagery CGS (AI CGS) operation. While this level of integration provides a wealth of valuable information, it also increases the complexity of planning, assessment and exploitation which in turn dictates flexible simulation tools for mission rehearsal and operator training. MITRE has developed a ModSAF-driven model for a UAV equipped with a moving target indicator (MTI) radar for wide-area surveillance, and a Battlefield Combat Identification System (BCIS) for positive identification of friendly forces. The imaging functions are performed by integrating the UAV model with visualization software in order to render the sensors view in real-time. This model forms the basis for a multisensor CGS simulation (MSCGS) which consists of the multisensor UAV combined with a UAV Control Station (UAV CS). The UAV CS controls imaging task assignments which take place when an MTI track is selected for imaging by means of a mouse click entry on an active MTI display. At that time, the UAV is commanded to fly an automatically determined trajectory in order to align itself for the imaging task. A beam footprint whose position, size and shape is determined by the sensor position, attitude, and field-of-view appears on the display as an indication of the relationship of the image display to the terrain in the operational scenario. A three-dimensional visualization of the designated target area then takes place on a separate display.

Deborah J. Violette Pierce; John J. Santapietro

1998-01-01

181

An REU project on the design of a brushless DC machine for plug-in hybrid electric vehicles  

Microsoft Academic Search

This paper proposes a design methodology for the propulsion motor of a plug-in hybrid electric vehicle. This research was conducted through the Research Experiences for Undergraduates (REU) program supported by National Science Foundation (NSF). The simulation of a representative plug-in hybrid electric vehicle has been performed using ADVISOR vehicle modeling software. The vehicle has been simulated over a set of

Alex J. Borsuk; Berker Bilgin; Alireza Khaligh; Mahesh Krishnamurthy

2011-01-01

182

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Problems related to an unmanned exploration of the planet Mars by means of an autonomous roving planetary vehicle are investigated. These problems include: design, construction and evaluation of the vehicle itself and its control and operating systems. More specifically, vehicle configuration, dynamics, control, propulsion, hazard detection systems, terrain sensing and modelling, obstacle detection concepts, path selection, decision-making systems, and chemical analyses of samples are studied. Emphasis is placed on development of a vehicle capable of gathering specimens and data for an Augmented Viking Mission or to provide the basis for a Sample Return Mission.

Gisser, D. G.; Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Yerazunis, S. Y.

1975-01-01

183

Third Conference on Fibrous Composites in Flight Vehicle Design, part 1  

NASA Technical Reports Server (NTRS)

The use of fibrous composite materials in the design of aircraft and space vehicle structures and their impact on future vehicle systems are discussed. The topics covered include: flight test work on composite components, design concepts and hardware, specialized applications, operational experience, certification and design criteria. Contributions to the design technology base include data concerning material properties, design procedures, environmental exposure effects, manufacturing procedures, and flight service reliability. By including composites as baseline design materials, significant payoffs are expected in terms of reduced structural weight fractions, longer structural life, reduced fuel consumption, reduced structural complexity, and reduced manufacturing cost.

1976-01-01

184

Design study of an integrated aerobraking orbital transfer vehicle  

NASA Technical Reports Server (NTRS)

An aerobraking orbital transfer vehicle (AOTV) concept, which has an aerobrake structure that is integrated with the propulsion stage, is discussed. The concept vehicle is to be assembled in space and is space-based. The advantages of aeroassist over an all propulsive vehicle are discussed and it is shown that the vehicle considered is very competitive with inflatable and deployable concepts from mass and performance aspects. The aerobrake geometry is an ellipsoidally blunted, raked-off, elliptical wide-angle cone with a toroidal skirt. Propellant tanks, engines, and subsystems are integrated into a closed, isogrid aerobrake structure which provides rigidity. The vehicle has two side-firing, gimbaled RL-10 type engines and carries 38,000 kg of useable propellant. The trajectory during aerobraking is determined from an adaptive guidance logic, and the heating is determined from engineering correlations as well as 3-D Navier-Stokes solutions. The AOTV is capable of placing 13,500 kg payload into geosynchronous Earth orbit (GEO) or carrying a LEO-GEO-LEO round-trip payload of 7100 kg. A two-stage version considered for lunar missions results in a lunar surface delivery capability of 18,000 kg or a round-trip capability of 6800 kg with 3860 kg delivery-only capability.

Scott, C. D.; Roberts, B. B.; Nagy, K.; Taylor, P.; Gamble, J. D.; Ceremeli, C. J.; Knoll, K. R.; Li, C. P.; Reid, R. C.

1985-01-01

185

Design and fabrication of metallic thermal protection systems for aerospace vehicles  

NASA Technical Reports Server (NTRS)

A program was conducted to develop a lightweight, efficient metallic thermal protection system (TPS) for application to future shuttle-type reentry vehicles, advanced space transports, and hypersonic cruise vehicles. Technical requirements were generally derived from the space shuttle. A corrugation-stiffened beaded-skin TPS design was used as a baseline. The system was updated and modified to incorporate the latest technology developments and design criteria. The primary objective was to minimize mass for the total system.

Varisco, A.; Bell, P.; Wolter, W.

1978-01-01

186

System design and optimization of the world's fastest hydrogen fuel cell vehicle  

Microsoft Academic Search

The Buckeye Bullet 2 is the world's fastest hydrogen fuel cell electric vehicle, with a certified FIA record of 487.433 km\\/hr (302.877 mi\\/hr). This paper provides the basic details of the overall vehicle and focuses on the design, testing, and optimization of the propulsion system. A unique fuel cell system was designed, tested, and integrated to produce over 500 kW

Edward Hillstrom; Kevin Ponziani; Benjamin Sinshiemer; Carington Bork; Marcello Canova; Yann Guezennec; Giorgio Rizzoni; Mike Procter

2010-01-01

187

Preliminary power train design for a state-of-the-art electric vehicle (executive summary)  

NASA Technical Reports Server (NTRS)

The preliminary design of a state-of-the-art electric power train is part of a national effort to reap the potential benefit of useful urban electric passenger vehicles. Outlined in a detailed presentation are: (1) assessment of the state-of-the-art in electric vehicle technology; (2) state-of-the-art power train design; (3) improved power train; and (4) summary and recommendations.

1978-01-01

188

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration  

NASA Technical Reports Server (NTRS)

Investigation of problems related to control of a mobile planetary vehicle according to a systematic plan for the exploration of Mars has been undertaken. Problem areas receiving attention include: (1) overall systems analysis; (2) vehicle configuration and dynamics; (3) toroidal wheel design and evaluation; (4) on-board navigation systems; (5) satellite-vehicle navigation systems; (6) obstacle detection systems; (7) terrain sensing, interpretation and modeling; (8) computer simulation of terrain sensor-path selection systems; and (9) chromatographic systems design concept studies. The specific tasks which have been undertaken are defined and the progress which has been achieved during the period July 1, 1971 to December 31, 1971 is summarized.

Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Smith, E. J.; Yerazunis, S. W.

1971-01-01

189

Power converter design for a fuel cell electric vehicle  

Microsoft Academic Search

This research is developed the electric vehicle by the fuel cell. Between fuel cell source and motor controller, we add new power converter, offer steady output voltage to motor controller and drive the direct current hub motor. Converter not only offers steady output voltage but it also combines with coupling inductance technology to battery charger. Besides offers energy to drive

Van-Tsai Liu; Jia-Wei Hong; Kuo-Ching Tseng

2010-01-01

190

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

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

191

Flight Test Experiment Design for Characterizing Stability and Control of Hypersonic Vehicles  

NASA Technical Reports Server (NTRS)

A maneuver design method that is particularly well-suited for determining the stability and control characteristics of hypersonic vehicles is described in detail. Analytical properties of the maneuver design are explained. The importance of these analytical properties for maximizing information content in flight data is discussed, along with practical implementation issues. Results from flight tests of the X-43A hypersonic research vehicle (also called Hyper-X) are used to demonstrate the excellent modeling results obtained using this maneuver design approach. A detailed design procedure for generating the maneuvers is given to allow application to other flight test programs.

Morelli, Eugene A.

2008-01-01

192

The design of an airfoil for a high-altitude, long-endurance remotely piloted vehicle  

NASA Technical Reports Server (NTRS)

Airfoil design efforts are studied. The importance of integrating airfoil and aircraft designs was demonstrated. Realistic airfoil data was provided to aid future high altitude, long endurance aircraft preliminary design. Test cases were developed for further validation of the Eppler program. Boundary layer, not pressure distribution or shape, was designed. Substantial improvement was achieved in vehicle performance through mission specific airfoil designed utilizing the multipoint capability of the Eppler program.

Maughmer, Mark D.; Somers, Dan M.

1987-01-01

193

Preliminary design for a space based orbital transfer vehicle  

NASA Technical Reports Server (NTRS)

A space-based orbital transfer vehicle has been sized for a 50-metric-ton payload delivery from low-earth-orbit to a geosynchronous orbit. Space basing effected substantial reductions in cryogenic insulation, tank, and body structure. The tank and body structural masses are shown to be lower for space basing because of the larger difference in acceleration loads between the on-orbit case (0.2 g's) and delivery (3.0 g's), the latter applying to ground-based vehicles which are delivered to orbit fully loaded with propellants. Insulation masses are lower because of the absence of an atmosphere and the attendant heat transfer losses. Insulation systems masses are also reduced because of the elimination of the problem of liquefaction and freezing of moisture on the tanks.

Macconochie, I. O.; Rehder, J. J.; Brien, E. P.

1979-01-01

194

Dual throat engine design for a SSTO launch vehicle  

NASA Technical Reports Server (NTRS)

A propulsion system analysis of a dual fuel, dual throat engine for launch vehicle application was conducted. Basic dual throat engine characterization data are presented to allow vehicle optimization studies to be conducted. A preliminary baseline engine system was defined. Dual throat engine performance, envelope, and weight parametric data were generated over the parametric range of thrust from 890 to 8896 KN (200K to 2M lb-force), chamber pressure from 6.89 million to 34.5 million N/sq m (1000 to 5000 psia) thrust ratio from 1.2 to 5, and a range of mixture ratios for the two tripropellant combinations: LO2/RP-1 + LH2 and LO2/LCH4 + LH2. The results of the study indicate that the dual fuel dual throat engine is a viable single stage to orbit candidate.

Obrien, C. J.; Salmon, J. W.

1980-01-01

195

Estimating Logistics Support of Reusable Launch Vehicles During Conceptual Design  

NASA Technical Reports Server (NTRS)

Methods exist to define the logistics support requirements for new aircraft concepts but are not directly applicable to new launch vehicle concepts. In order to define the support requirements and to discriminate among new technologies and processing choices for these systems, NASA Langley Research Center (LaRC) is developing new analysis methods. This paper describes several methods under development, gives their current status, and discusses the benefits and limitations associated with their use.

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

1997-01-01

196

A New Handbook for the Development of Space Vehicle Terrestrial Environment Design Requirements.  

NASA Technical Reports Server (NTRS)

A new NASA document entitled "Terrestrial Environment (Climatic) Criteria Handbook for Use in Aerospace Vehicle Development (NASA-HDBK-1001A) has been developed. The Handbook provides terrestrial environment information, data bases, models, recommendations, etc. for use in the design, development, trade studies, testing, and mission analyses for space (or launch) .vehicles. This document is organized into fourteen specific natural environment disciplines of which some are winds, atmospheric models, thermal radiation, precipitation-for-icing, cloud cover, atmospheric electricity, geologic hazards, toxic chemical release by propulsion systems, and sea state. Atmospheric phenomena play a significant role in the design and flight of aerospace vehicles and in the integrity of the associated aerospace systems and structures. Environmental design criteria guidelines in this document are based on measurements and observations of atmospheric and climatic phenomena relative to various aerospace development, operational, and vehicle launch locations. The natural environment criteria guidelines data presented in this Handbook were formulated based on discussions with and requests from engineers involved in aerospace vehicle development and operations. Therefore, they represent responses to actual engineering problems and are not just a general compilation of environmental data. The Handbook addresses the basis for the information presented, the interpretations of the terrestrial environment guideline given in the Handbook, and its application to the development of aerospace vehicle design requirements. Specific examples of the Handbook content and associated "lessons lenmed" are given in this paper.

Johnson, Dale L.; Vaughan, William W.

2008-01-01

197

A New Handbook for the Development of Space Vehicle Terrestrial Environment Design Requirements  

NASA Technical Reports Server (NTRS)

A new NASA document entitled "Terrestrial Environment (Climatic) Criteria Handbook for Use in Aerospace Vehicle Development (NASA-HDBK-IOO1A) has been developed. The Handbook provides terrestrial environment information, data bases, models, recommendations, etc. for use in the design, development, trade studies, testing, and mission analyses for space (or launch) vehicles. This document is organized into fourteen specific natural environment disciplines of which some are winds, atmospheric models, thermal radiation, precipitation-for-icing, cloud cover, atmospheric electricity, geologic hazards, toxic chemical release by propulsion systems, and sea state. Atmospheric phenomena play a significant role in the design and flight of aerospace vehicles and in the integrity of the associated aerospace systems and structures. Environmental design criteria guidelines in this document are based on measurements and observations of atmospheric and climatic phenomena relative to various aerospace development, operational, and vehicle launch locations. The natural environment criteria guidelines data presented in this Handbook were formulated based on discussions with and requests from engineers involved in aerospace vehicle development and operations. Therefore, they represent responses to actual engineering problems and are not just a general compilation of environmental data. The Handbook addresses the basis for the information presented, the interpretations of the terrestrial environment guideline given in the Handbook, and its application to the development of aerospace vehicle design requirements. Specific examples of the Handbook content and associated "lessons lenmed" are given in this paper.

Johnson, Dale L.; Vaughan, William W.

2008-01-01

198

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

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

199

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

NASA Technical Reports Server (NTRS)

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 3-D 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.

Erickson, Gary E.; Peake, David J.; Delfrate, John; Skow, Andrew M.; Malcolm, Gerald N.

1987-01-01

200

Systems Analysis and Structural Design of an Unpressurized Cargo Delivery Vehicle  

NASA Technical Reports Server (NTRS)

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.

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

2007-01-01

201

Structural Design and Analysis of Un-pressurized Cargo Delivery Vehicle  

NASA Technical Reports Server (NTRS)

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.

Martinovic, Zoran N.

2007-01-01

202

Design of an agile unmanned combat vehicle: a product of the DARPA UGCV program  

NASA Astrophysics Data System (ADS)

The unmanned ground compat vehicle (UGCV) design evolved by the SAIC team on the DARPA UGCV Program is summarized in this paper. This UGCV design provides exceptional performance against all of the program metrics and incorporates key attributes essential for high performance robotic combat vehicles. This performance includes protection against 7.62 mm threats, C130 and CH47 transportability, and the ability to accept several relevant weapons payloads, as well as advanced sensors and perception algorithms evolving from the PerceptOR program. The UGCV design incorporates a combination of technologies and design features, carefully selected through detailed trade studies, which provide optimum performance against mobility, payload, and endurance goals without sacrificing transportability, survivability, or life cycle cost. The design was optimized to maximize performance against all Category I metrics. In each case, the performance of this design was validated with detailed simulations, indicating that the vehicle exceeded the Category I metrics. Mobility metrics were analyzed using high fidelity VisualNastran vehicle models, which incorporate the suspension control algorithms and controller cycle times. DADS/Easy 5 3-D models and ADAMS simulations were also used to validate vehicle dynamics and control algorithms during obstacle negotiation.

Thornhill, Lindsey D.; Walls, Alan; Arkin, Ronald C.; Beno, Joseph H.; Bergh, Chuck; Bresie, Don; Giovannetti, Anthony; Gothard, Benny M.; Matthies, Larry H.; Nogueiro, Porfirio; Scanlon, Jim; Scott, Ron; Simon, Miguel; Smith, Wilford; Waldron, Kenneth J.

2003-09-01

203

A Large-Scale Design Integration Approach Developed in Conjunction with the Ares Launch Vehicle Program  

NASA Technical Reports Server (NTRS)

This paper presents a method for performing large-scale design integration, taking a classical 2D drawing envelope and interface approach and applying it to modern three dimensional computer aided design (3D CAD) systems. Today, the paradigm often used when performing design integration with 3D models involves a digital mockup of an overall vehicle, in the form of a massive, fully detailed, CAD assembly; therefore, adding unnecessary burden and overhead to design and product data management processes. While fully detailed data may yield a broad depth of design detail, pertinent integration features are often obscured under the excessive amounts of information, making them difficult to discern. In contrast, the envelope and interface method results in a reduction in both the amount and complexity of information necessary for design integration while yielding significant savings in time and effort when applied to today's complex design integration projects. This approach, combining classical and modern methods, proved advantageous during the complex design integration activities of the Ares I vehicle. Downstream processes, benefiting from this approach by reducing development and design cycle time, include: Creation of analysis models for the Aerodynamic discipline; Vehicle to ground interface development; Documentation development for the vehicle assembly.

Redmon, John W.; Shirley, Michael C.; Kinard, Paul S.

2012-01-01

204

Advanced design of valve-regulated leadacid battery for hybrid electric vehicles  

Microsoft Academic Search

A novel design of lead-acid battery has been developed for use in hybrid electric vehicles HEVs . The battery has current take-offs at both ends of each of the positive and negative plates. This feature markedly reduces battery operating temperatures, improves battery . capacity, and extends cycle-life under HEV duty. The battery also performs well under partial-state-of-charge PSoC rfast-charge, electric-vehicle

L. T. Lam; R. H. Newnham; H. Ozgun; F. A. Fleming

2000-01-01

205

Adaptive guidance law design based on characteristic model for reentry vehicles  

Microsoft Academic Search

In this paper an adaptive guidance law based on the characteristic model is designed to track a reference drag acceleration\\u000a for reentry vehicles like the Shuttle. The characteristic modeling method of linear constant systems is extended for single-input\\u000a and single-output (SISO) linear time-varying systems so that the characteristic model can be established for reentry vehicles.\\u000a A new nonlinear differential golden-section

Junchun Yang; Jun Hu; Maolin Ni

2008-01-01

206

The critical role of aerodynamic heating effects in the design of hypersonic vehicles  

NASA Technical Reports Server (NTRS)

Hypersonic vehicles operate in a hostile aerothermal environment, which has a significant impact on their aerothermostructural performance. Significant coupling occurs between the aerodynamic flow field, structural heat transfer, and structural response, creating a multidisciplinary interaction. The critical role of aerodynamic heating effects in the design of hypersonic vehicles is identified with an example of high localized heating on an engine-cowl leading edge. Recent advances is integrated fluid-thermal-structural finite-element analyses are presented.

Wieting, Allan R.

1989-01-01

207

Design of an innovative lead-acid battery for electric and hybrid vehicles  

NASA Astrophysics Data System (ADS)

An innovative lead acid battery was designed specifically for use in a hybrid car. The battery has exceeded all of the minimum performance goals, and in many cases the optimistic target goals. The eV-1300, which features electrolyte circulation, has excellent energy density, power characteristics, efficiency, and cycle life. It is a good candidate battery for other hybrid vehicles and electric vehicles which require a relatively small cell size.

Baxa, M. S.; Weinlein, C. E.

208

Multidisciplinary design of a rocket-based combined cycle SSTO launch vehicle using Taguchi methods  

NASA Technical Reports Server (NTRS)

Results are presented from the optimization process of a winged-cone configuration SSTO launch vehicle that employs a rocket-based ejector/ramjet/scramjet/rocket operational mode variable-cycle engine. The Taguchi multidisciplinary parametric-design method was used to evaluate the effects of simultaneously changing a total of eight design variables, rather than changing them one at a time as in conventional tradeoff studies. A combination of design variables was in this way identified which yields very attractive vehicle dry and gross weights.

Olds, John R.; Walberg, Gerald D.

1993-01-01

209

Development of integrated programs for Aerospace-vehicle Design (IPAD): Product program management systems  

NASA Technical Reports Server (NTRS)

The Integrated Programs for Aerospace Vehicle Design (IPAD) is a computing system to support company-wide design information processing. This document presents a brief description of the management system used to direct and control a product-oriented program. This document, together with the reference design process (CR 2981) and the manufacture interactions with the design process (CR 2982), comprises the reference information that forms the basis for specifying IPAD system requirements.

Isenberg, J. M.; Southall, J. W.

1979-01-01

210

Engineering and design of vehicles for long distance road transport of livestock (ruminants, pigs and poultry).  

PubMed

During road transportation, livestock are subjected to a number of concurrent potential stressors that can increase mortality and morbidity and compromise welfare status and production efficiency. A major concern is the thermal micro-environment within the vehicle with both heat stress and cold stress constituting major problems. It is possible to mitigate the effects of external climatic conditions by improving vehicle design and operation using engineering solutions that match 'on-board' environmental conditions with the biological requirements of the animals. This review describes an investigative approach that targets four elements. These are the thermal conditions on commercial transport vehicles under a range of climatic conditions, the 'thermal comfort zones' or target conditions for different livestock species, the heat and moisture loads upon vehicles that must be dissipated and the thermodynamic characteristics of animal transport vehicles that affect the design of mechanical or active ventilation systems able to function at maximum efficiency under everyday commercial conditions. Results of research around these four elements can provide the sound scientific basis for improved vehicle design and operation and for legislation and codes of practice aimed at optimising animal welfare and productivity in relation to transportation of livestock on journeys of both long and short duration. PMID:20405426

Mitchell, Malcolm A; Kettlewell, Peter J

2008-01-01

211

Theory and Design of Flight-Vehicle Engines  

NASA Technical Reports Server (NTRS)

Papers are presented on such topics as the testing of aircraft engines, errors in the experimental determination of the parameters of scramjet engines, the effect of the nonuniformity of supersonic flow with shocks on friction and heat transfer in the channel of a hypersonic ramjet engine, and the selection of the basic parameters of cooled GTE turbines. Consideration is also given to the choice of optimal total wedge angle for the acceleration of aerospace vehicles, the theory of an electromagnetic-resonator engine, the dynamic characteristics of the pumps and turbines of liquid propellant rocket engines in transition regimes, and a hierarchy of mathematical models for spacecraft control engines.

Zhdanov, V. T. (editor); Kurziner, R. I. (editor)

1987-01-01

212

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

NASA Technical Reports Server (NTRS)

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.

1991-01-01

213

Cross Layer Design for Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks  

E-print Network

Cross Layer Design for Mobile Ad-Hoc Unmanned Aerial Vehicle Communication Networks Abdel Ilah of wireless network that is formed by a collection of mobile nodes. Each node in such network has the coverage area and reduce the number of hops. Meanwhile, we designed a new Medium Access Control (MAC

Dong, Liang

214

CONCEPTUAL DESIGN ISSUE: DEVELOPING A NEW HIGHWAY VEHICLE EMISSION ESTIMATION METHODOLOGY  

EPA Science Inventory

The paper reports on EPA's effort to define the design of an ideal methodology for estimating emissions from highway vehicles. The design concept will be used by EPA to focus research and promote the availability of accurate, cost effective inventory procedures within 5 to 10 yea...

215

A Study of Design and Control of a Quadruped Walking Vehicle  

Microsoft Academic Search

The paper addresses some of the fundamental problems of energy efficiency, design, and adaptive gait control of quadru ped walking vehicles. The design principle of a leg called a gravitationally decoupled actuator (GDA) is shown to be indispensable for realizing energetically efficient walking mo tion. A novel mechanism, the three-dimensional Cartesian- coordinate pantograph (PANTOMEC), which follows the GDA principle and

Shigeo Hirose

1984-01-01

216

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

NASA Technical Reports Server (NTRS)

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.

Mukhopadhyay, Vivek

2007-01-01

217

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

Code of Federal Regulations, 2012 CFR

...vehicle use on designated roads and trails and in designated...administrative unit of the National Forest System...official shall monitor the effects of motor vehicle use on designated roads and trails and in designated areas under the jurisdiction of...

2012-07-01

218

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

Code of Federal Regulations, 2013 CFR

...vehicle use on designated roads and trails and in designated...administrative unit of the National Forest System...official shall monitor the effects of motor vehicle use on designated roads and trails and in designated areas under the jurisdiction of...

2013-07-01

219

CAD-Based Design Optimization for Vehicle Performance  

Microsoft Academic Search

This paper presents an open and integrated tool environment that enables engineers to effectively search, in a CAD solid model form, for a mechanism design with optimal kinematic and dynamic performance. In order to demonstrate the feasibility of such an environment, design parameterization that supports capturing design intents in product solid models must be available, and advanced modeling, simulation, and

Kuang-Hua Chang; Sung-Hwan Joo

220

Conceptual Design and Cost Estimate of a Subsonic NASA Testbed Vehicle (NTV) for Aeronautics Research  

NASA Technical Reports Server (NTRS)

A conceptual design and cost estimate for a subsonic flight research vehicle designed to support NASA's Environmentally Responsible Aviation (ERA) project goals is presented. To investigate the technical and economic feasibility of modifying an existing aircraft, a highly modified Boeing 717 was developed for maturation of technologies supporting the three ERA project goals of reduced fuel burn, noise, and emissions. This modified 717 utilizes midfuselage mounted modern high bypass ratio engines in conjunction with engine exhaust shielding structures to provide a low noise testbed. The testbed also integrates a natural laminar flow wing section and active flow control for the vertical tail. An eight year program plan was created to incrementally modify and test the vehicle, enabling the suite of technology benefits to be isolated and quantified. Based on the conceptual design and programmatic plan for this testbed vehicle, a full cost estimate of $526M was developed, representing then-year dollars at a 50% confidence level.

Nickol, Craig L.; Frederic, Peter

2013-01-01

221

Performance and operational considerations in the design of vehicle antennas for mobile satellite communications  

NASA Technical Reports Server (NTRS)

This paper examines the vehicle antenna requirements for mobile satellite systems. The antenna parameters are discussed in the light of the requirements and the limitations in performance imposed by the physical constraints of antenna and by vehicle geometries. Measurements of diffraction and antenna noise temperature in an operational environment are examined, as well as their effects on system margins. Mechanical versus electronic designs are compared with regards to performance, cost, reliability, and design complexity. Comparisons between open-loop and close-loop tracking systems are made and the effects of bandwidth, sidelobe levels, operational constraints, vehicle angular velocity, and acceleration are discussed. Some consideration is given to the use of hybrid systems employing both open and closed-loop tracking. Changes to antenna/terminal specifications are recommended which will provide greater design flexibility and increase the likelihood of meeting the performance and operational requirements.

Milne, R.

1995-01-01

222

Resilient design of recharging station networks for electric transportation vehicles  

SciTech Connect

As societies shift to 'greener' means of transportation using electricity-driven vehicles one critical challenge we face is the creation of a robust and resilient infrastructure of recharging stations. A particular issue here is the optimal location of service stations. In this work, we consider the placement of battery replacing service station in a city network for which the normal traffic flow is known. For such known traffic flow, the service stations are placed such that the expected performance is maximized without changing the traffic flow. This is done for different scenarios in which roads, road junctions and service stations can fail with a given probability. To account for such failure probabilities, the previously developed facility interception model is extended. Results show that service station failures have a minimal impact on the performance following robust placement while road and road junction failures have larger impacts which are not mitigated easily by robust placement.

Kris Villez; Akshya Gupta; Venkat Venkatasubramanian

2011-08-01

223

Multi-disciplinary design optimization of subsonic fixed-wing unmanned aerial vehicles projected through 2025  

NASA Astrophysics Data System (ADS)

Through this research, a robust aircraft design methodology is developed for analysis and optimization of the Air Vehicle (AV) segment of Unmanned Aerial Vehicle (UAV) systems. The analysis functionality of the AV design is integrated with a Genetic Algorithm (GA) to form an integrated Multi-disciplinary Design Optimization (MDO) methodology for optimal AV design synthesis. This research fills the gap in integrated subsonic fixed-wing UAV AV MDO methods. No known single methodology captures all of the phenomena of interest over the wide range of UAV families considered here. Key advancements include: (1) parametric Low Reynolds Number (LRN) airfoil aerodynamics formulation, (2) UAV systems mass properties definition, (3) wing structural weight methods, (4) self-optimizing flight performance model, (5) automated geometry algorithms, and (6) optimizer integration. Multiple methods are provided for many disciplines to enable flexibility in functionality, level of detail, computational expediency, and accuracy. The AV design methods are calibrated against the High-Altitude Long-Endurance (HALE) Global Hawk, Medium-Altitude Endurance (MAE) Predator, and Tactical Shadow 200 classes, which exhibit significant variations in mission performance requirements and scale from one another. All three UAV families show significant design gross weight reductions as technology improves. The overall technology synergy experienced 10--11 years after the initial technology year is 6.68% for Global Hawk, 7.09% for Predator, and 4.22% for the Shadow 200, which means that the technology trends interact favorably in all cases. The Global Hawk and Shadow 200 families exhibited niche behavior, where some vehicles attained higher aerodynamic performance while others attained lower structural mass fractions. The high aerodynamic performance Global Hawk vehicles had high aspect ratio wings with sweep, while the low structural mass fraction vehicles had straight, relatively low aspect ratios and smaller wing spans. The high aerodynamic performance Shadow 200 vehicles had relatively low wing loadings and large wing spans, while the lower structural mass fraction counterparts sought to minimize physical size. (Abstract shortened by UMI.)

Gundlach, John Frederick, IV

224

Topology, Design, Analysis, and Thermal Management of Power Electronics for Hybrid Electric Vehicle Applications  

SciTech Connect

Power electronics circuits play an important role in the success of electric, hybrid and fuel cell vehicles. Typical power electronics circuits in hybrid vehicles include electric motor drive circuits and DC/DC converter circuits. Conventional circuit topologies, such as buck converters, voltage source inverters and bidirectional boost converters are challenged by system cost, efficiency, controllability, thermal management, voltage and current capability, and packaging issues. Novel topologies, such as isolated bidirectional DC/DC converters, multilevel converters, and Z-source inverters, offer potential improvement to hybrid vehicle system performance, extended controllability and power capabilities. This paper gives an overview of the topologies, design, and thermal management, and control of power electronics circuits in hybrid vehicle applications.

Mi, C.; Peng, F. Z.; Kelly, K. J.; O'Keefe, M.; Hassani, V.

2008-01-01

225

Design and cost study for development of lead-acid batteries suitable for electric vehicle propulsion  

NASA Astrophysics Data System (ADS)

A design for an improved state-of-the-art (ISOA) battery is proposed. It is believed that this ISOA design is the most efficient design achievable within the constraints of the ISOA battery development program. These constraints include realistic time and financial limitations, and compatibility with existing highspeed production equipment. The ISOA battery is in fact an improved, state-of-the-art lead acid battery for use in an electric vehicle. A durable, light weight polypropylene container and cover complete with single point watering and venting features are incorporated in the ISOA design. A number of materials and process parameters with profound affect on battery performance were chosen after extensive evaluation and cell testing. Development of an advanced lead acid electric vehicle battery involved the evaluation and application of effective forward concepts in the design of the battery. Many weight-saving designs were incorporated. Significant improvements in active material efficiencies and integrity are required.

Weinlein, C. E.

226

Launch Vehicle Design and Optimization Methods and Priority for the Advanced Engineering Environment  

NASA Technical Reports Server (NTRS)

NASA's Advanced Engineering Environment (AEE) is a research and development program that will improve collaboration among design engineers for launch vehicle conceptual design and provide the infrastructure (methods and framework) necessary to enable that environment. In this paper, three major technical challenges facing the AEE program are identified, and three specific design problems are selected to demonstrate how advanced methods can improve current design activities. References are made to studies that demonstrate these design problems and methods, and these studies will provide the detailed information and check cases to support incorporation of these methods into the AEE. This paper provides background and terminology for discussing the launch vehicle conceptual design problem so that the diverse AEE user community can participate in prioritizing the AEE development effort.

Rowell, Lawrence F.; Korte, John J.

2003-01-01

227

Computer modeling in the design and evaluation of electric and hybrid vehicles  

SciTech Connect

This demonstration project uses modern simulation techniques to illustrate the important technologies and design variables that an auto-designer would consider in production a high efficiency, low emissions vehicle. Simulation and modeling techniques use the idea of capturing the relationships between real components of the systems with mathematical equations. These equations are then solved on a computer to simulate the behavior or performance of the system under various conditions. In the current demonstration project, we focus on many variations of a hydrogen-powered vehicle.

Aceves, S.M.; Smith, J.R. [Lawrence Livermore National Lab., CA (United States); Johnson, N.L. [Los Alamos National Lab., NM (United States)

1996-08-16

228

Improving Conceptual Design for Launch Vehicles. The Bimese Concept: A Study of Mission and Economic Options  

NASA Technical Reports Server (NTRS)

This report summarizes key activities conducted in the third and final year of the cooperative agreement NCC1-229 entitled "Improving Conceptual Design for Launch Vehicles." This project has been funded by the Vehicle Analysis Branch at NASA's Langley Research Center in Hampton, VA. Work has been performed by the Space Systems Design Lab (SSDL) at the Georgia Institute of Technology, Atlanta, GA. Accomplishments during the first and second years of this project have been previously reported in annual progress reports. This report will focus on the third and final year of the three year activity.

Olds, John R.; Tooley, Jeffrey

1999-01-01

229

Concurrent trajectory and conceptual vehicle design optimization of an aerobatic air race aircraft  

NASA Astrophysics Data System (ADS)

This paper deals with the development of a framework for the concurrent optimization of trajectory and conceptual vehicle design. The tool is applied to the design of an aerobatic air race aircraft that is required to fly a prescribed slalom course consisting of inflatable pylons in the fastest possible time. It is shown that when the aircraft design is tailored to the characteristics of the race track, an improvement in the lap time of about 1 percent can be achieved.

Visser, Hendrikus G.; Liem, Christiaan

2014-10-01

230

Design and Control Methodology of Plug-in Hybrid Electric Vehicles  

Microsoft Academic Search

This paper systematically discusses the design and control methodologies of a plug-in hybrid electric vehicle (PHEV). Design methodology is focused on battery energy and power capacity design. Two kinds of typical batteries, namely, NiMH and Li-ion, are discussed. Control strategies focus on all electric range and charge depletion range operations. In addition, a constrained engine on and off control strategy

Yimin Gao; Mehrdad Ehsani

2010-01-01

231

Design and control methodology of plug-in hybrid electric vehicles  

Microsoft Academic Search

This paper systematically discussed the design and control methodology of plug-in hybrid electric vehicle (PHEV). Design methodology focused on battery energy and power capacity design. Two lands of typical batteries-NiMH and Li-ion have been discussed. Control strategies focused on all electric range (AER) and charge depletion range (CDR) operations. Also, a constrained engine on and off control strategy has been

Yimin Gao; Mehrdad Ehsani

2008-01-01

232

Development of Integrated Programs for Aerospace-Vehicle Design (IPAD) - IPAD user requirements  

NASA Technical Reports Server (NTRS)

Results of a requirements analysis task for Integrated Programs for Aerospace Vehicle Design (IPAD) are presented. User requirements which, in part, will shape the IPAD system design are given. Requirements considered were: generation, modification, storage, retrieval, communication, reporting, and protection of information. Data manipulation and controls on the system and the information were also considered. Specific needs relative to the product design process are also discussed.

Anderton, G. L.

1979-01-01

233

System design of the Pioneer Venus spacecraft. Volume 4: Probe bus and orbiter spacecraft vehicle studies  

NASA Technical Reports Server (NTRS)

The requirements, trades, and design descriptions for the probe bus and orbiter spacecraft configurations, structure, thermal control, and harness are defined. Designs are developed for Thor/Delta and Atlas/Centaur launch vehicles with the latter selected as the final baseline. The major issues examined in achieving the baseline design are tabulated. The importance of spin axis orientation because of the effect on science experiments and earth communications is stressed.

Bozajian, J. M.

1973-01-01

234

Fixed solar array designs for GPS space vehicles  

NASA Astrophysics Data System (ADS)

A risk reduction approach for the Global Positioning Satellite (GPS) replenishment satellite block which uses fixed rather than tracking solar arrays is described. This design study was carried out as a result of reliability and electromagnetic interference (EMI) concerns with solar array drive power and transfer systems (SADPT). Fixed solar array designs eliminate the need for a SADPT, but result in larger arrays than tracking arrays in order to maintain acceptable end-of-life (EOL) performance. The weight increase due to the larger array is partially compensated for by the elimination of the SADPT. If advanced solar arrays and/or lightweight array designs are used, fixed array designs can lead to weight savings over baseline silicon cell-based designs.

Malachesky, P. A.; Simburger, E. J.; Zwibel, H. S.

235

Decomposition-Based Decision Making for Aerospace Vehicle Design  

NASA Technical Reports Server (NTRS)

Most practical engineering systems design problems have multiple and conflicting objectives. Furthermore, the satisfactory attainment level for each objective ( requirement ) is likely uncertain early in the design process. Systems with long design cycle times will exhibit more of this uncertainty throughout the design process. This is further complicated if the system is expected to perform for a relatively long period of time, as now it will need to grow as new requirements are identified and new technologies are introduced. These points identify a need for a systems design technique that enables decision making amongst multiple objectives in the presence of uncertainty. Traditional design techniques deal with a single objective or a small number of objectives that are often aggregates of the overarching goals sought through the generation of a new system. Other requirements, although uncertain, are viewed as static constraints to this single or multiple objective optimization problem. With either of these formulations, enabling tradeoffs between the requirements, objectives, or combinations thereof is a slow, serial process that becomes increasingly complex as more criteria are added. This research proposal outlines a technique that attempts to address these and other idiosyncrasies associated with modern aerospace systems design. The proposed formulation first recasts systems design into a multiple criteria decision making problem. The now multiple objectives are decomposed to discover the critical characteristics of the objective space. Tradeoffs between the objectives are considered amongst these critical characteristics by comparison to a probabilistic ideal tradeoff solution. The proposed formulation represents a radical departure from traditional methods. A pitfall of this technique is in the validation of the solution: in a multi-objective sense, how can a decision maker justify a choice between non-dominated alternatives? A series of examples help the reader to observe how this technique can be applied to aerospace systems design and compare the results of this so-called Decomposition-Based Decision Making to more traditional design approaches.

Borer, Nicholas K.; Mavris, DImitri N.

2005-01-01

236

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

NASA Technical Reports Server (NTRS)

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.

Gollan, Rowan J.; Smart, Michael K.

2010-01-01

237

Solar Electric Propulsion Vehicle Design Study for Cargo Transfer to Earth-moon L1  

NASA Technical Reports Server (NTRS)

A design study for a cargo transfer vehicle using solar electric propulsion was performed for NASA's Revolutionary Aerospace Systems Concepts program. Targeted for 2016, the solar electric propulsion (SEP) transfer vehicle is required to deliver a propellant supply module with a mass of approximately 36 metric tons from Low Earth Orbit to the first Earth-Moon libration point (LL1) within 270 days. Following an examination of propulsion and power technology options, a SEP transfer vehicle design was selected that incorporated large-area (approx. 2700 sq m) thin film solar arrays and a clustered engine configuration of eight 50 kW gridded ion thrusters mounted on an articulated boom. Refinement of the SEP vehicle design was performed iteratively to properly estimate the required xenon propellant load for the out-bound orbit transfer. The SEP vehicle performance, including the xenon propellant estimation, was verified via the SNAP trajectory code. Further efforts are underway to extend this system model to other orbit transfer missions.

Sarver-Verhey, Timothy R.; Kerslake, Thomas W.; Rawlin, Vincent K.; Falck, Robert D.; Dudzinski, Leonard J.; Oleson, Steven R.

2002-01-01

238

Bioresearch Module Design Definition and Space Shuttle Vehicle Integration Study. Volume 1: Basic Report  

NASA Technical Reports Server (NTRS)

Preliminary designs of the Bioexplorer spacecraft, developed in an earlier study program, are analyzed and updated to conform to a new specification which includes use of both the Scout and the space shuttle vehicle for launch. The updated spacecraft is referred to as bioresearch module. It is capable of supporting a variety of small biological experiments in near-earth and highly elliptical earth orbits. The baseline spacecraft design is compatible with the Scout launch vehicle. Inboard profile drawings, weight statements, interface drawings, and spacecraft parts and aerospace ground equipment lists are provided to document the design. The baseline design was analyzed to determine the design and cost impact of a set of optional features. These include reduced experiment power and thermal load, addition of an experiment television monitor, and replacement of VHF with S-band communications. The impact of these options on power required, weight change and cost is defined.

Lang, A. L., Jr.

1971-01-01

239

Electric vehicle design, racing and distance to empty algorithms  

E-print Network

This research began with the goal of designing and building an electric motorcycle to compete in the Isle of Man TT Zero race. A set of parametric physics-based models was derived to size the batteries and motors, predict ...

Rodgers, Lennon Patrick

2013-01-01

240

ODIN - Optimal Design Integration system for synthesis of aerospace vehicles  

NASA Technical Reports Server (NTRS)

The ODIN system is a new design synthesis procedure for solving multiple discipline design problems. In ODIN an unlimited number of independent technology codes can be linked together in the computer in any desired sequence. This paper describes the ODIN system, the executive program DIALOG, the data management technique, and the program library. The use of ODIN is illustrated with an application drawn from space system studies.

Rau, T. R.; Decker, J. P.

1974-01-01

241

A wireless sensor network design and implementation for vehicle detection, classification, and tracking  

NASA Astrophysics Data System (ADS)

Vehicle intrusion is considered a significant threat for critical zones specially the militarized zones and therefore vehicles monitoring has a great importance. In this paper a small wireless sensor network for vehicle intrusion monitoring consists of a five inexpensive sensor nodes distributed over a small area and connected with a gateway using star topology has been designed and implemented. The system is able to detect a passage of an intrusive vehicle, classify it either wheeled or tracked, and track the direction of its movement. The approach is based on Vehicle's ground vibrations for detection, vehicle's acoustic signature for classification and the Energy- based target localization for tracking. Detection and classification are implemented by using different algorithms and techniques including Analog to Digital Conversion, Fast Fourier Transformation (FFT) and Neural Network .All of these algorithms and techniques are implemented locally in the sensor node using Microchip dsPIC digital signal controller. Results are sent from the sensor node to the gateway using ZigBee technology and then from the gateway to a web server using GPRS technology.

Aljaafreh, A.; Al Assaf, A.

2013-05-01

242

LifeSat engineering in-house vehicle design  

NASA Technical Reports Server (NTRS)

The LifeSat program was initiated to research the effects of microgravity and cosmic radiation on living organisms. The effects of long-term human exposure to free-space radiation fields over a range of gravitational environments has long been recognized as one of the primary design uncertainties for human space exploration. A critical design issue in the radiation biology requirements was the lack of definition of the minimum radiation absorbed dosage required to produce statistically meaningful data. The Phase A study produced a spacecraft conceptual design resembling a Discoverer configuration with a total weight of approximately 2800 pounds that would carry a 525-pound payload module (45 inches in diameter and 36 inches long) and support up to 12 rodents and a general biology module supporting lower life forms for an on-orbit duration of up to 60 days. The phase B conceptual designs focused on gravitational biology requirements and only briefly addressed the design impacts of the shift toward radiobiological science that occurred during the latter half of the Phase B studies.

Adkins, A.; Badhwar, G.; Bryant, L.; Caram, J.; Conley, G.; Crull, T.; Cuthbert, P.; Darcy, E.; Delaune, P.; Edeen, M.

1992-01-01

243

Advanced Usage of Vehicle Sketch Pad for CFD-Based Conceptual Design  

NASA Technical Reports Server (NTRS)

Conceptual design is the most fluid phase of aircraft design. It is important to be able to perform large scale design space exploration of candidate concepts that can achieve the design intent to avoid more costly configuration changes in later stages of design. This also means that conceptual design is highly dependent on the disciplinary analysis tools to capture the underlying physics accurately. The required level of analysis fidelity can vary greatly depending on the application. Vehicle Sketch Pad (VSP) allows the designer to easily construct aircraft concepts and make changes as the design matures. More recent development efforts have enabled VSP to bridge the gap to high-fidelity analysis disciplines such as computational fluid dynamics and structural modeling for finite element analysis. This paper focuses on the current state-of-the-art geometry modeling for the automated process of analysis and design of low-boom supersonic concepts using VSP and several capability-enhancing design tools.

Ordaz, Irian; Li, Wu

2013-01-01

244

Design considerations and prototype implementation of a piezoelectrically driven micro-vehicle for the internal inspection of small diameter pipes  

Microsoft Academic Search

The initial design and the prototype implementation of a micro-vehicle is presented. This micro- vehicle is capable of moving internally and simultaneously inspecting pipe systems with a diameter between 40mm to110mm. The driving motors are chosen to be of ultrasonic piezoelectric type, due to their high torque and compact design characteristics. The structure of the vehicle is modular, based on

I. KATSIKAS; I. KATSOULIS; I. ANTONIADIS

245

Applying Monte Carlo Simulation to Launch Vehicle Design and Requirements Verification  

NASA Technical Reports Server (NTRS)

This paper is focused on applying Monte Carlo simulation to probabilistic launch vehicle design and requirements verification. The approaches developed in this paper can be applied to other complex design efforts as well. Typically the verification must show that requirement "x" is met for at least "y" % of cases, with, say, 10% consumer risk or 90% confidence. Two particular aspects of making these runs for requirements verification will be explored in this paper. First, there are several types of uncertainties that should be handled in different ways, depending on when they become known (or not). The paper describes how to handle different types of uncertainties and how to develop vehicle models that can be used to examine their characteristics. This includes items that are not known exactly during the design phase but that will be known for each assembled vehicle (can be used to determine the payload capability and overall behavior of that vehicle), other items that become known before or on flight day (can be used for flight day trajectory design and go/no go decision), and items that remain unknown on flight day. Second, this paper explains a method (order statistics) for determining whether certain probabilistic requirements are met or not and enables the user to determine how many Monte Carlo samples are required. Order statistics is not new, but may not be known in general to the GN&C community. The methods also apply to determining the design values of parameters of interest in driving the vehicle design. The paper briefly discusses when it is desirable to fit a distribution to the experimental Monte Carlo results rather than using order statistics.

Hanson, John M.; Beard, Bernard B.

2010-01-01

246

Conceptual Design of a Vertical Takeoff and Landing Unmanned Aerial Vehicle with 24-HR Endurance  

NASA Technical Reports Server (NTRS)

This paper describes a conceptual design study for a vertical takeoff and landing (VTOL) unmanned aerial vehicle (UAV) that is able to carry a 25-lb science payload for 24 hr and is able to land and take off at elevations as high as 15,000 ft without human intervention. In addition to the science payload, this vehicle must be able to carry a satellite communication system, and the vehicle must be able to be transported in a standard full-size pickup truck and assembled by only two operators. This project started with a brainstorming phase to devise possible vehicle configurations that might satisfy the requirements. A down select was performed to select a near-term solution and two advanced vehicle concepts that are better suited to the intent of the mission. Sensitivity analyses were also performed on the requirements and the technology levels to obtain a better understanding of the design space. This study found that within the study assumptions the mission is feasible; the selected concepts are recommended for further development.

Fredericks, William J.

2010-01-01

247

Development of a dedicated ethanol ultra-low emission vehicle (ULEV) system design  

SciTech Connect

The objective of this 3.5 year project is to develop a commercially competitive vehicle powered by ethanol (or ethanol blend) that can meet California`s ultra-low emission vehicle (ULEV) standards and equivalent corporate average fuel economy (CAFE) energy efficiency for a light-duty passenger car application. The definition of commercially competitive is independent of fuel cost, but does include technical requirements for competitive power, performance, refueling times, vehicle range, driveability, fuel handling safety, and overall emissions performance. This report summarizes a system design study completed after six months of effort on this project. The design study resulted in recommendations for ethanol-fuel blends that shall be tested for engine low-temperature cold-start performance and other criteria. The study also describes three changes to the engine, and two other changes to the vehicle to improve low-temperature starting, efficiency, and emissions. The three engine changes are to increase the compression ratio, to replace the standard fuel injectors with fine spray injectors, and to replace the powertrain controller. The two other vehicle changes involve the fuel tank and the aftertreatment system. The fuel tank will likely need to be replaced to reduce evaporative emissions. In addition to changes in the main catalyst, supplemental aftertreatment systems will be analyzed to reduce emissions before the main catalyst reaches operating temperature.

Bourn, G.; Callahan, T.; Dodge, L.; Mulik, J.; Naegeli, D.; Shouse, K.; Smith, L.; Whitney, K. [Southwest Research Inst., San Antonio, TX (United States)

1995-02-01

248

Highway Aesthetics: The Design of Motor Vehicles. Teaching Art with Art.  

ERIC Educational Resources Information Center

Addresses the design of highway vehicles as one means for students to learn about forms of three-dimensional art. Focuses on the Corvette, mass-produced cars like the Chrysler Concorde, the modern semi-trailer, and an antique 1931 Dusenberg Model J Murphy Aluminum Top Coupe. (CMK)

Hubbard, Guy

1999-01-01

249

Particle Swarm Optimization for energy management fuzzy controller design in dual-source electric vehicle  

Microsoft Academic Search

How to distribute the power between battery bank and supercapacitor modules to obtain good performance is a vital problem in dual-source electric vehicles. Traditional fuzzy controller design for energy management relies too much on the expert experience, and is easy to get the sub-optimal performance. in order to overcome this drawback, particle swarm optimization (PSO) is introduced for energy management

Zhang Chenghui; Shi Qingsheng; Cui Naxin; Li Wuhua

2007-01-01

250

Grid Generation for Multidisciplinary Design and Optimization of an Aerospace Vehicle: Issues and Challenges  

NASA Technical Reports Server (NTRS)

The purpose of this paper is to discuss grid generation issues and to challenge the grid generation community to develop tools suitable for automated multidisciplinary analysis and design optimization of aerospace vehicles. Special attention is given to the grid generation issues of computational fluid dynamics and computational structural mechanics disciplines.

Samareh, Jamshid A.

2000-01-01

251

Motor design considerations and test results of an interior permanent magnet synchronous motor for electric vehicles  

Microsoft Academic Search

This paper describes the high performance motor design of an interior permanent magnet synchronous motor (IPM motor) for electric vehicles. The authors examined the differences in motor characteristics based on how the magnets were embedded. For this comparison, they set conditions so that the volume of magnets remained constant, and they used both computer simulation and experiments with a prototype

Yukio Honda; Tomokazu Nakamura; Toshiro Higaki; Yoji Takeda

1997-01-01

252

Design of a 100 kW switched reluctance motor for electric vehicle propulsion  

Microsoft Academic Search

Low cost, high reliability, and competitive weight and efficiency combine to make the switched reluctance (SR) motor drive a strong candidate for application in future electric vehicle (EV) propulsion systems. This paper presents methods and results of a prototype SR motor design study. Finite element analysis and transient simulation results predict performance, efficiency, and weight that are competitive with existing

Tatsuya Uematsu; Richard S. Wallace

1995-01-01

253

Design of a mechanism for biaxial rotation of a wing for a hovering vehicle  

Microsoft Academic Search

This paper presents a novel mechanism to actuate the wings of a hovering micro air vehicle (MAV). The mechanism uses a single actuator, but each wing can rotate about two orthogonal axes. The goal of this work is to design a light-weight compact mechanism that flaps the wings, inspired from the wing motion of hummingbird and hovering insects, to generate

Sean H. McIntosh; Sunil K. Agrawal; Zaeem Khan

2006-01-01

254

Design of a Mechanism for Biaxial Rotation of a Wing for a Hovering Vehicle  

Microsoft Academic Search

This paper presents a novel mechanism to actuate the wings of a hovering micro air vehicle (MAV). The mechanism uses a single actuator, but each wing can rotate about two orthogonal axes. The goal of this work is to design a light-weight compact mechanism that flaps the wings, inspired from the wing motion of hummingbird and hovering insects, to generate

Sean H. McIntosh; Sunil K. Agrawal; Zaeem Khan

2006-01-01

255

Setting initial targets in vehicle side impact safety design using regression-based modeling  

Microsoft Academic Search

The performance of a vehicle in a side impact safety assessment test can be influenced by a number of parameters which can be categorized under structural, packaging, and restraint system-related areas. One way of setting design variable targets in initial stages for desirable side impact safety performance is to use reliable regression-based relations developed with the aid of test data.

A Deb; K S Cheruvu

2007-01-01

256

Design and analysis of an anti-slip fuzzy controller for heavy duty off road vehicles  

Microsoft Academic Search

This paper illustrates the design and analysis of a distributed fuzzy control system to prevent wheel slippage in heavy-duty off-road vehicles with hydrostatic power transmission using the vector space analytical approach. The controller described have been fully implemented in a commercially available city tractor and tested on a test track as well as under real working conditions

Jorg-Michael Hasemann; K. Kansala; Yang-Ming Pok

1994-01-01

257

Design and operational requirements for a reusable launch vehicle  

NASA Astrophysics Data System (ADS)

Equipment design, system layout, and operational requirements of reusable launch vechicles are discussed. It is suggested that environmental qualification and lifetime limitations must be reconsidered for extended use of equipment and checkout and accessibility provisions must be enhanced to reduce turnaround time and cost. Spare hardware, procedures and skilled personnel must be available at the launch site for system and equipment maintenance.

Levod, J.

258

AEVITA : designing biomimetic vehicle-to-pedestrian communication protocols for autonomously operating & parking on-road electric vehicles  

E-print Network

With research institutions from various private, government and academic sectors performing research into autonomous vehicle deployment strategies, the way we think about vehicles must adapt. But what happens when the ...

Pennycooke, Nicholas (Nicholas D.)

2012-01-01

259

Hover and wind-tunnel testing of shrouded rotors for improved micro air vehicle design  

Microsoft Academic Search

The shrouded-rotor configuration has emerged as the most popular choice for rotary-wing Micro Air Vehicles (MAVs), because of the inherent safety of the design and the potential for significant performance improvements. However, traditional design philosophies based on experience with large-scale ducted propellers may not apply to the low-Reynolds-number (20,000) regime in which MAVs operate. An experimental investigation of the effects

Jason L. Pereira

2008-01-01

260

On Design and Development of an Intelligent Mobile Robotic Vehicle for StairCase Navigation  

Microsoft Academic Search

\\u000a The present chapter focuses on the study of different features of stair-climbing mechanisms for transporting materials autonomously.\\u000a The authors finally concentrate on arm wheel-based design for stair climbing. An attempt is made to design, develop and construct\\u000a a mobile robotic vehicle for stair navigation with the following functional attributes: (i) motion on plane surface, (ii)\\u000a navigation on stair- case, i.e.,

Ranjit Ray; Bikash Bepari; Subhasis Bhaumik

2010-01-01

261

Design of high-efficiency and high-torque-density switched reluctance motor for vehicle propulsion  

Microsoft Academic Search

A high-density and high-efficiency switched reluctance (SR) motor has been designed and built for vehicle propulsion. Extensive finite-element analyses have been carried out to optimize the geometry for high density. Steady-state performance of the drive has been simulated to ensure good efficiency at all speeds. Special attention has been given during machine design to lower the acoustic noise. Direct liquid

Khwaja M. Rahman; Steven E. Schulz

2002-01-01

262

The Role of Uncertainty in Aerospace Vehicle Analysis and Design  

NASA Technical Reports Server (NTRS)

Effective uncertainty quantification (UQ) begins at the earliest phase in the design phase for which there are adequate models and continues tightly integrated to the analysis and design cycles as the refinement of the models and the fidelity of the tools increase. It is essential that uncertainty quantification strategies provide objective information to support the processes of identifying, analyzing and accommodating for the effects of uncertainty. Assessments of uncertainty should never render the results more difficult for engineers and decision makers to comprehend, but instead provide them with critical information to assist with resource utilization decisions and risk mitigation strategies. Success would be measured by the tools to enable engineers and decision makers to effectively balance critical project resources against system requirements while accounting for the impact of uncertainty.

Kenny, Sean P.; Crespo, Luis G.

2011-01-01

263

Optimal design for hybrid rocket engine for air launch vehicle  

Microsoft Academic Search

A feasibility study and the optimal design was conducted for the application of a hybrid motor with HTPB\\/LOX combination to\\u000a the first stage of an air launch system. The feasibility analysis showed that the hybrid motor could successfully be used\\u000a as a substitute for the solid rocket motor of the first stage of the Pegasus XL if the average specific

Ihnseok Rhee; Changjin Lee; Jae-Woo Lee

2008-01-01

264

Development of a conceptual flight vehicle design weight estimation method library and documentation  

NASA Astrophysics Data System (ADS)

The state of the art in estimating the volumetric size and mass of flight vehicles is held today by an elite group of engineers in the Aerospace Conceptual Design Industry. This is not a skill readily accessible or taught in academia. To estimate flight vehicle mass properties, many aerospace engineering students are encouraged to read the latest design textbooks, learn how to use a few basic statistical equations, and plunge into the details of parametric mass properties analysis. Specifications for and a prototype of a standardized engineering "tool-box" of conceptual and preliminary design weight estimation methods were developed to manage the growing and ever-changing body of weight estimation knowledge. This also bridges the gap in Mass Properties education for aerospace engineering students. The Weight Method Library will also be used as a living document for use by future aerospace students. This "tool-box" consists of a weight estimation method bibliography containing unclassified, open-source literature for conceptual and preliminary flight vehicle design phases. Transport aircraft validation cases have been applied to each entry in the AVD Weight Method Library in order to provide a sense of context and applicability to each method. The weight methodology validation results indicate consensus and agreement of the individual methods. This generic specification of a method library will be applicable for use by other disciplines within the AVD Lab, Post-Graduate design labs, or engineering design professionals.

Walker, Andrew S.

265

The promise of air cargo: System aspects and vehicle design  

NASA Technical Reports Server (NTRS)

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.

Whitehead, A. H., Jr.

1976-01-01

266

Preliminary Design of a Manned Nuclear Electric Propulsion Vehicle Using Genetic Algorithms  

NASA Technical Reports Server (NTRS)

Nuclear electric propulsion (NEP) vehicles will be needed for future manned missions to Mars and beyond. Candidate designs must be identified for further detailed design from a large array of possibilities. Genetic algorithms have proven their utility in conceptual design studies by effectively searching a large design space to pinpoint unique optimal designs. This research combined analysis codes for NEP subsystems with a genetic algorithm. The use of penalty functions with scaling ratios was investigated to increase computational efficiency. Also, the selection of design variables for optimization was considered to reduce computation time without losing beneficial design search space. Finally, trend analysis of a reference mission to the asteroids yielded a group of candidate designs for further analysis.

Irwin, Ryan W.; Tinker, Michael L.

2005-01-01

267

Preliminary Design of a Manned Nuclear Electric Propulsion Vehicle Using Genetic Algorithms  

SciTech Connect

Nuclear electric propulsion (NEP) vehicles will be needed for future manned missions to Mars and beyond. Candidate designs must be identified for further detailed design from a large array of possibilities. Genetic algorithms have proven their utility in conceptual design studies by effectively searching a large design space to pinpoint unique optimal designs. This research combined analysis codes for NEP subsystems with a genetic algorithm. The use of penalty functions with scaling ratios was investigated to increase computational efficiency. Also, the selection of design variables for optimization was considered to reduce computation time without losing beneficial design search space. Finally, trend analysis of a reference mission to the asteroids yielded a group of candidate designs for further analysis.

Irwin, Ryan W. [School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907 (United States); Tinker, Michael L. [Spacecraft and Vehicle Systems Department, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)

2005-02-06

268

Reductions in vehicle fuel consumption due to refinements in aerodynamic design. [for trailer trucks  

NASA Technical Reports Server (NTRS)

Over-the-highway fuel consumption and coastdown drag tests were performed on cab-over-engine, van type trailer trucks and modifications of these vehicles incorporating refinements in aerodynamic design. In addition, 1/25-scale models of these configurations, and derivatives of these configurations were tested in a wind tunnel to determine the effects of wind on the magnitude of the benefits that aerodynamic refinements can provide. The results of these tests are presented for a vehicle incorporating major redesign features and for a relatively simple add-on modification. These results include projected fuel savings on the basis of annual savings per vehicle year as well as probable nationwide fuel savings.

Saltzman, E. J.

1979-01-01

269

A Design for Composing and Extending Vehicle Models  

NASA Technical Reports Server (NTRS)

The Systems Development Branch (SDB) at NASA Langley Research Center (LaRC) creates simulation software products for research. Each product consists of an aircraft model with experiment extensions. SDB treats its aircraft models as reusable components, upon which experiments can be built. SDB has evolved aircraft model design with the following goals: 1. Avoid polluting the aircraft model with experiment code. 2. Discourage the copy and tailor method of reuse. The current evolution of that architecture accomplishes these goals by reducing experiment creation to extend and compose. The architecture mechanizes the operational concerns of the model's subsystems and encapsulates them in an interface inherited by all subsystems. Generic operational code exercises the subsystems through the shared interface. An experiment is thus defined by the collection of subsystems that it creates ("compose"). Teams can modify the aircraft subsystems for the experiment using inheritance and polymorphism to create variants ("extend").

Madden, Michael M.; Neuhaus, Jason R.

2003-01-01

270

Concept Design of a Crash Management System for Goods Vehicles  

NSDL National Science Digital Library

In this study by the European Aluminium Association and FKA (Forschungsgesellschaft Kraftfahrwesen Aachen), a concept crash system for 40t trucks is developed based on the front end design used in the APROSYS study. The concept was built around European safety regulations in CAD software and simulated with an FE model using aluminum and steel. It was found that using an octagon shaped aluminum crush box would be the safest due to its characteristics of low weight, high energy absorption, and low technical complexity. Through additional testing it was also found if EU directive 96/53/EC could be modified to exclude cabin dimensions from its requirements, safer collisions for both parties would result.

2013-07-10

271

Evaluation of Separation Mechanism Design for the Orion/Ares Launch Vehicle  

NASA Technical Reports Server (NTRS)

As a part of the preliminary design work being performed for the Orion vehicle, the Orion to Spacecraft Adaptor (SA) separation mechanism was analyzed and sized, with findings presented here. Sizing is based on worst case abort condition as a result of an anomaly driving the launch vehicle engine thrust vector control hard-over causing a severe vehicle pitch over. This worst case scenario occurs just before Upper Stage Main Engine Cut-Off (MECO) when the vehicle is the lightest and the damping effect due to propellant slosh has been reduced to a minimum. To address this scenario and others, two modeling approaches were invoked. The first approach was a detailed 2-D (Simulink) model to quickly assess the Service Module Engine nozzle to SA clearance for a given separation mechanism. The second approach involved the generation of an Automatic Dynamic Analysis of Mechanical Systems (ADAMS) model to assess secondary effects due to mass centers of gravity that were slightly off the vehicle centerline. It also captured any interference between the Solar Arrays and the Spacecraft Adapter. A comparison of modeling results and accuracy are discussed. Most notably, incorporating a larger SA flange diameter allowed for a natural separation of the Orion and its engine nozzle even at relatively large pitch rates minimizing the kickoff force. Advantages and disadvantages of the 2-D model vs. a full 3-D (ADAMS) model are discussed as well.

Konno, Kevin E.; Catalano, Daniel A.; Krivanek, Thomas M.

2008-01-01

272

Evaluation of Separation Mechanism Design for the Orion/Ares Launch Vehicle  

NASA Technical Reports Server (NTRS)

As a part of the preliminary design work being performed for the Orion vehicle, the Orion to Spacecraft Adaptor (SA) separation mechanism mechanism was analyzed and sized, with findings presented here. Sizing is based on worst case abort condition as a result of an anomaly driving the launch vehicle engine thrust vector control hard-over causing a severe vehicle pitch over. This worst case scenario occurs just before Upper Stage Main Engine Cut-Off (MECO) when the vehicle is the lightest and the damping effect due to propellant slosh has been reduced to a minimum. To address this scenario and others, two modeling approaches were invoked. The first approach was a detailed Simulink model to quickly assess the Service Module Engine nozzle to SA clearance for a given separation mechanism. The second approach involved the generation of an Automatic Dynamic Analysis of Mechanical Systems (ADAMS) model to assess secondary effects due to mass centers of gravity that were slightly off the vehicle centerline. It also captured any interference between the Solar Arrays and the Spacecraft Adapter. A comparison of modeling results and accuracy are discussed. Most notably, incorporating a larger SA flange diameter allowed for a natural separation of the Orion and its engine nozzle even at relatively large pitch rates minimizing the kickoff force. Advantages and disadvantages of the Simulink model vs. a full geometric ADAMS model are discussed as well.

Konno, Kevin E.; Catalano, Daniel A.; Krivanek, Thomas M.

2008-01-01

273

Evaluation of Separation Mechanism Design for the Orion/Ares Launch Vehicle  

NASA Technical Reports Server (NTRS)

As a part of the preliminary design work being performed for the Orion vehicle, the Orion to Spacecraft Adaptor (SA) separation mechanism was analyzed and sized, with findings presented here. Sizing is based on worst case abort condition as a result of an anomaly driving the launch vehicle engine thrust vector control hard-over causing a severe vehicle pitch over. This worst case scenario occurs just before Upper Stage Main Engine Cut-Off (MECO) when the vehicle is the lightest and the damping effect due to propellant slosh has been reduced to a minimum. To address this scenario and others, two modeling approaches were invoked. The first approach was a detailed Simulink model to quickly assess the Service Module Engine nozzle to SA clearance for a given separation mechanism. The second approach involved the generation of an Automatic Dynamic Analysis of Mechanical Systems (ADAMS) model to assess secondary effects due to mass centers of gravity that were slightly off the vehicle centerline. It also captured any interference between the Solar Arrays and the Spacecraft Adapter. A comparison of modeling results and accuracy are discussed. Most notably, incorporating a larger SA flange diameter allowed for a natural separation of the Orion and it's engine nozzle even at relatively large pitch rates minimizing the kickoff force. Advantages and disadvantages of the Simulink model vs. a full geometric ADAMS model are discussed as well.

Konno, Kevin E.; Catalano, Daniel A.; Krivanek, Thomas M.

2008-01-01

274

Design for Reliability and Safety Approach for the New NASA Launch Vehicle  

NASA Technical Reports Server (NTRS)

The United States National Aeronautics and Space Administration (NASA) is in the midst of a space exploration program intended for sending crew and cargo to the international Space Station (ISS), to the moon, and beyond. This program is called Constellation. As part of the Constellation program, NASA is developing new launch vehicles aimed at significantly increase safety and reliability, reduce the cost of accessing space, and provide a growth path for manned space exploration. Achieving these goals requires a rigorous process that addresses reliability, safety, and cost upfront and throughout all the phases of the life cycle of the program. This paper discusses the "Design for Reliability and Safety" approach for the NASA new launch vehicles, the ARES I and ARES V. Specifically, the paper addresses the use of an integrated probabilistic functional analysis to support the design analysis cycle and a probabilistic risk assessment (PRA) to support the preliminary design and beyond.

Safie, Fayssal M.; Weldon, Danny M.

2007-01-01

275

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles  

NASA Technical Reports Server (NTRS)

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the model development and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Cognata, Thomas J.; Leimkuehler, Thomas O.; Sheth, Rubik B.; Le,Hung

2012-01-01

276

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles  

NASA Technical Reports Server (NTRS)

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the modeling and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Cognata, Thomas J.; Leimkuehler, Thomas; Sheth, Rubik; Le, Hung

2013-01-01

277

Design optimization of the electrically peaking hybrid (ELPH) vehicle. Research report  

SciTech Connect

Electrically Peaking Hybrid (ELPH) is a parallel hybrid electric vehicle propulsion concept that was invented at Texas A and M University, by the advanced vehicle systems research group. Over the past six years, design methodologies, component development, and system optimization work has been going on for this invention. This project was a first attempt in integrating the above developments into an optimized design of an ELPH passenger car. Design specifications were chosen for a full size passenger car, performing as well as any conventional car, over the EPA-FTP-75 combined city/highway drive cycles. The results of this design project were two propulsion systems. Both were appropriate for commercial production, from the points of view of cost, availability of the technologies, and components. One utilized regenerative braking and the other did not. Substantial fuel savings and emissions reductions resulted from simulating these designs on the FTP-75 drive cycle. For example, the authors` ELPH full size car, with regenerative braking, was capable of delivering over 50 miles per gallon in city driving, with corresponding reductions in its emissions. This project established the viability of the authors` ELPH concept and their design methodologies, in computer simulations. More work remains to be done on investigating more advanced power plants, such as fuel cells, and more advanced components, such as switched reluctance motor drives, for the authors` designs. Furthermore, the authors` design optimization can be carried out to more detailed levels, for prototyping and production.

Ehsani, M.; Gao, Y.; Butler, K.

1998-10-01

278

Application of advanced multidisciplinary analysis and optimization methods to vehicle design synthesis  

NASA Technical Reports Server (NTRS)

Advanced multidisciplinary analysis and optimization methods, namely system sensitivity analysis and non-hierarchical system decomposition, are applied to reduce the cost and improve the visibility of an automated vehicle design synthesis process. This process is inherently complex due to the large number of functional disciplines and associated interdisciplinary couplings. Recent developments in system sensitivity analysis as applied to complex non-hierarchic multidisciplinary design optimization problems enable the decomposition of these complex interactions into sub-processes that can be evaluated in parallel. The application of these techniques results in significant cost, accuracy, and visibility benefits for the entire design synthesis process.

Consoli, Robert David; Sobieszczanski-Sobieski, Jaroslaw

1990-01-01

279

Preliminary structural design of a lunar transfer vehicle aerobrake. M.S. Thesis  

NASA Technical Reports Server (NTRS)

An aerobrake concept for a Lunar transfer vehicle was weight optimized through the use of the Taguchi design method, structural finite element analyses and structural sizing routines. Six design parameters were chosen to represent the aerobrake structural configuration. The design parameters included honeycomb core thickness, diameter to depth ratio, shape, material, number of concentric ring frames, and number of radial frames. Each parameter was assigned three levels. The minimum weight aerobrake configuration resulting from the study was approx. half the weight of the average of all twenty seven experimental configurations. The parameters having the most significant impact on the aerobrake structural weight were identified.

Bush, Lance B.

1992-01-01

280

Practices in adequate structural design. [of space vehicles and space systems  

NASA Technical Reports Server (NTRS)

An account is given of the guidelines for safe and reliable space vehicle design, especially in the structural engineering area, which have been formulated by NASA in the aftermath of the Space Shuttle Challenger accident in 1986. Illustrative examples are presented from state-of-the-art, performance-driven hardware whose design ineluctably gives rise to a high sensitivity to small variations and uncertainties. It is recommended that such hardware be designed with a view to easy inspectability and manufacturability, with emphasis on the role played in system structures by fracture mechanics. Static and dynamic coupling effects must be precluded wherever possible.

Ryan, Robert S.

1989-01-01

281

Needs and Opportunities for Uncertainty-Based Multidisciplinary Design Methods for Aerospace Vehicles  

NASA Technical Reports Server (NTRS)

This report consists of a survey of the state of the art in uncertainty-based design together with recommendations for a Base research activity in this area for the NASA Langley Research Center. This report identifies the needs and opportunities for computational and experimental methods that provide accurate, efficient solutions to nondeterministic multidisciplinary aerospace vehicle design problems. Barriers to the adoption of uncertainty-based design methods are identified. and the benefits of the use of such methods are explained. Particular research needs are listed.

Zang, Thomas A.; Hemsch, Michael J.; Hilburger, Mark W.; Kenny, Sean P; Luckring, James M.; Maghami, Peiman; Padula, Sharon L.; Stroud, W. Jefferson

2002-01-01

282

Conceptual design of the AE481 Demon Remotely Piloted Vehicle (RPV)  

NASA Technical Reports Server (NTRS)

This project report presents a conceptual design for a high speed remotely piloted vehicle (RPV). The AE481 Demon RPV is capable of performing video reconnaissance missions and electronic jamming over hostile territory. The RPV cruises at a speed of Mach 0.8 and an altitude of 300 feet above the ground throughout its mission. It incorporates a rocket assisted takeoff and a parachute-airbag landing. Missions are preprogrammed, but in-flight changes are possible. The Demon is the answer to a military need for a high speed, low altitude RPV. The design methods, onboard systems, and avionics payload are discussed in this conceptual design report along with economic viability.

Hailes, Chris; Kolver, Jill; Nestor, Julie; Patterson, Mike; Selow, Jan; Sagdeo, Pradip; Katz, Kenneth

1994-01-01

283

Building Operations Efficiencies into NASA's Ares I Crew Launch Vehicle Design  

NASA Technical Reports Server (NTRS)

The U.S. Vision for Space Exploration guides the National Aeronautics and Space Administration's (NASA's) challenging missions that expand humanity's boundaries and open new routes to the space frontier. With the Agency's commitment to complete the International Space Station (ISS) and to retire the venerable Space Shuttle by 2010, the NASA Administrator commissioned the Exploration Systems Architecture Study (ESAS) in 2005 to analyze options for safe, simple, cost-efficient launch solutions that could deliver human-rated space transportation capabilities in a timely manner within fixed budget guidelines. The Exploration Launch Projects (ELP) Office, chartered by the Constellation Program in October 2005, has been conducting systems engineering studies and business planning to successively refine the design configurations and better align vehicle concepts with customer and stakeholder requirements, such as significantly reduced life-cycle costs. As the Agency begins the process of replacing the Shuttle with a new generation of spacecraft destined for missions beyond low-Earth orbit to the Moon and Mars, NASA is designing the follow-on crew and cargo launch systems for maximum operational efficiencies. To sustain the long-term exploration of space, it is imperative to reduce the $4 billion NASA typically spends on space transportation each year. This paper gives toplevel information about how the follow-on Ares I Crew Launch Vehicle (CLV) is being designed for improved safety and reliability, coupled with reduced operations costs. These methods include carefully developing operational requirements; conducting operability design and analysis; using the latest information technology tools to design and simulate the vehicle; and developing a learning culture across the workforce to ensure a smooth transition between Space Shuttle operations and Ares vehicle development.

Dumbacher, Daniel L.; Davis, Stephan R.

2007-01-01

284

Quantum dots as a platform for nanoparticle drug delivery vehicle design  

PubMed Central

Nanoparticle-based drug delivery (NDD) has emerged as a promising approach to improving upon the efficacy of existing drugs and enabling the development of new therapies. Proof-of-concept studies have demonstrated the potential for NDD systems to simultaneously achieve reduced drug toxicity, improved bio-availability, increased circulation times, controlled drug release, and targeting. However, clinical translation of NDD vehicles with the goal of treating particularly challenging diseases, such as cancer, will require a thorough understanding of how nanoparticle properties influence their fate in biological systems, especially in vivo. Consequently, a model system for systematic evaluation of all stages of NDD with high sensitivity, high resolution, and low cost is highly desirable. In theory, this system should maintain the properties and behavior of the original NDD vehicle, while providing mechanisms for monitoring intracellular and systemic nanocarrier distribution, degradation, drug release, and clearance. For such a model system, quantum dots (QDots) offer great potential. QDots feature small size and versatile surface chemistry, allowing their incorporation within virtually any NDD vehicle with minimal effect on overall characteristics, and offer superb optical properties for real-time monitoring of NDD vehicle transport and drug release at both cellular and systemic levels. Though the direct use of QDots for drug delivery remains questionable due to their potential long-term toxicity, the QDot core can be easily replaced with other organic drug carriers or more biocompatible inorganic contrast agents (such as gold and magnetic nanoparticles) by their similar size and surface properties, facilitating translation of well characterized NDD vehicles to the clinic, maintaining NDD imaging capabilities, and potentially providing additional therapeutic functionalities such as photothermal therapy and magneto-transfection. In this review we outline unique features that make QDots an ideal platform for nanocarrier design and discuss how this model has been applied to study NDD vehicle behavior for diverse drug delivery applications. PMID:23000745

Probst, Christine E.; Zrazhevskiy, Pavel; Bagalkot, Vaishali; Gao, Xiaohu

2012-01-01

285

Advanced design of valve-regulated lead-acid battery for hybrid electric vehicles  

NASA Astrophysics Data System (ADS)

A novel design of lead-acid battery has been developed for use in hybrid electric vehicles (HEVs). The battery has current take-offs at both ends of each of the positive and negative plates. This feature markedly reduces battery operating temperatures, improves battery capacity, and extends cycle-life under HEV duty. The battery also performs well under partial-state-of-charge (PSoC)/fast-charge, electric-vehicle operation. The improvements in performance are attributed to more uniform utilization of the plate active-materials. The battery, combined with an internal-combustion engine and a new type of supercapacitor, will be used to power an HEV, which is being designed and constructed by an Australian industry-government consortium.

Lam, L. T.; Newnham, R. H.; Ozgun, H.; Fleming, F. A.

286

Concept Design of High Power Solar Electric Propulsion Vehicles for Human Exploration  

NASA Technical Reports Server (NTRS)

Human exploration beyond low Earth orbit will require enabling capabilities that are efficient, affordable and reliable. Solar electric propulsion (SEP) has been proposed by NASA s Human Exploration Framework Team as one option to achieve human exploration missions beyond Earth orbit because of its favorable mass efficiency compared to traditional chemical propulsion systems. This paper describes the unique challenges associated with developing a large-scale high-power (300-kWe class) SEP vehicle and design concepts that have potential to meet those challenges. An assessment of factors at the subsystem level that must be considered in developing an SEP vehicle for future exploration missions is presented. Overall concepts, design tradeoffs and pathways to achieve development readiness are discussed.

Hoffman, David J.; Kerslake, Thomas W.; Hojnicki, Jeffrey S.; Manzella, David H.; Falck, Robert D.; Cikanek, Harry A., III; Klem, Mark D.; Free, James M.

2011-01-01

287

Development of Integrated Programs for Aerospace-vehicle design (IPAD): Integrated information processing requirements  

NASA Technical Reports Server (NTRS)

The engineering-specified requirements for integrated information processing by means of the Integrated Programs for Aerospace-Vehicle Design (IPAD) system are presented. A data model is described and is based on the design process of a typical aerospace vehicle. General data management requirements are specified for data storage, retrieval, generation, communication, and maintenance. Information management requirements are specified for a two-component data model. In the general portion, data sets are managed as entities, and in the specific portion, data elements and the relationships between elements are managed by the system, allowing user access to individual elements for the purpose of query. Computer program management requirements are specified for support of a computer program library, control of computer programs, and installation of computer programs into IPAD.

Southall, J. W.

1979-01-01

288

A graphical weather system design for the NASA transport systems research vehicle B-737  

NASA Technical Reports Server (NTRS)

A graphical weather system was designed for testing in the NASA Transport Systems Research Vehicle B-737 airplane and simulator. The purpose of these tests was to measure the impact of graphical weather products on aircrew decision processes, weather situation awareness, reroute clearances, workload, and weather monitoring. The flight crew graphical weather interface is described along with integration of the weather system with the flight navigation system, and data link transmission methods for sending weather data to the airplane.

Scanlon, Charles H.

1992-01-01

289

Design considerations for a lithium-aluminum\\/iron sulfide electric vehicle battery  

Microsoft Academic Search

A study has been made of battery-vehicle design interactions using a Toyota Carina converted to electric drive with a Li-Al\\/FeS battery used as a power and energy source. Energy and power requirements were calculated based on a range of 120 or 200 km with acceleration requirements typical of today's internal-combustion automobiles. Cell modeling analysis was employed to relate the specific

A. A. Chilenskas; E. C. Gay; H. Shimotake; D. L. Barney; K. Kawahara; K. Goto

1982-01-01

290

The 7.5K lbf thrust engine preliminary design for Orbit Transfer Vehicle  

Microsoft Academic Search

This document summarizes the preliminary design of the Aerojet version of the Orbit Transfer Vehicle main engine. The concept of a 7500 lbf thrust LO2\\/GH2 engine using the dual expander cycle for optimum efficiency is validated through power balance and thermal calculations. The engine is capable of 10:1 throttling from a nominal 2000 psia to a 200 psia chamber pressure.

Warren R. Hayden; Ralph Sabiers; Judy Schneider

1994-01-01

291

Design features of portable wheelchair ramps and their implications for curb and vehicle access.  

PubMed

This study evaluated a range of portable wheelchair ramps to highlight the effect of different product features on ease of use when wheelchair users climb curbs or access vehicles. Twelve portable ramps were evaluated. Although all the ramps were designed to load powered wheelchairs into motor vehicles, they were manufactured in different designs. The ramps were based on a "singlewide" platform or "channel" design. Some ramps had fixed dimensions, whereas others could be reduced in size because they were telescopic or designed to allow folding. Overall, the ramps could be divided into four subgroups on the basis of their key features. These were horizontally and longitudinally folding ramps, telescopic ramps, and ramps with fixed dimensions. The telescopic ramps could be subdivided into "U"-shaped gutter ramps and reverse profile ramps. Product appraisals and trials involving wheelchair users and caregivers of wheelchair users were done to evaluate each of these ramp designs. Although wheelchair ramps are available in a wide range of designs and configurations, we found that no single ramp design successfully met the needs of all wheelchair users or their caregivers. The evaluation highlighted a number of specific problems and potential hazards. Some ramps were found to move during a maneuver, showed poor stability when used with some vehicles, or were too narrow to allow wheelchair castors to pass through the channel without jamming. Some features, such as handles and locking mechanisms, influenced the ease with which the caregivers could use the ramps. Wheelchair users preferred the wide platform ramps because they were able to drive up these with ease and little preparation. The caregivers preferred folding or telescopic channel ramps because these were easier to handle and store. PMID:15543462

Storr, Tim; Spicer, Julie; Frost, Peggy; Attfield, Steve; Ward, Christopher D; Pinnington, Lorraine L

2004-05-01

292

Department of Mechanical and Nuclear Engineering Spring 2011 Shell 1 -Battery Electric Vehicle Chassis and Body Design  

E-print Network

, Texas. The team performed better than our projected performance. The Battery Electric Vehicle achievedPENNSTATE Department of Mechanical and Nuclear Engineering Spring 2011 Shell 1 - Battery Electric Vehicle Chassis and Body Design Overview The team faced the challenging task of redesigning a previous

Demirel, Melik C.

293

Environmental Controls and Life Support System (ECLSS) Design for a Multi-Mission Space Exploration Vehicle (MMSEV)  

NASA Technical Reports Server (NTRS)

Engineers at Johnson Space Center (JSC) are developing an Environmental Control and Life Support System (ECLSS) design for the Multi-Mission Space Exploration Vehicle (MMSEV). The purpose of the MMSEV is to extend the human exploration envelope for Lunar, Near Earth Object (NEO), or Deep Space missions by using pressurized exploration vehicles. The MMSEV, formerly known as the Space Exploration Vehicle (SEV), employs ground prototype hardware for various systems and tests it in manned and unmanned configurations. Eventually, the system hardware will evolve and become part of a flight vehicle capable of supporting different design reference missions. This paper will discuss the latest MMSEV ECLSS architectures developed for a variety of design reference missions, any work contributed toward the development of the ECLSS design, lessons learned from testing prototype hardware, and the plan to advance the ECLSS toward a flight design.

Stambaugh, Imelda; Baccus, Shelley; Naids, Adam; Hanford, Anthony

2012-01-01

294

Sustainable design for automotive products: dismantling and recycling of end-of-life vehicles.  

PubMed

The growth in automotive production has increased the number of end-of-life vehicles (ELVs) annually. The traditional approach ELV processing involves dismantling, shredding, and landfill disposal. The "3R" (i.e., reduce, reuse, and recycle) principle has been increasingly employed in processing ELVs, particularly ELV parts, to promote sustainable development. The first step in processing ELVs is dismantling. However, certain parts of the vehicle are difficult to disassemble and use in practice. The extended producer responsibility policy requires carmakers to contribute in the processing of scrap cars either for their own developmental needs or for social responsibility. The design for dismantling approach can be an effective solution to the existing difficulties in dismantling ELVs. This approach can also provide guidelines in the design of automotive products. This paper illustrates the difficulty of handling polymers in dashboards. The physical properties of polymers prevent easy separation and recycling by using mechanical methods. Thus, dealers have to rely on chemical methods such as pyrolysis. Therefore, car designers should use a single material to benefit dealers. The use of materials for effective end-of-life processing without sacrificing the original performance requirements of the vehicle should be explored. PMID:24326159

Tian, Jin; Chen, Ming

2014-02-01

295

Conceptual design of a flight validation mission for a Hypervelocity Asteroid Intercept Vehicle  

NASA Astrophysics Data System (ADS)

Near-Earth Objects (NEOs) are asteroids and comets whose orbits approach or cross Earth's orbit. NEOs have collided with our planet in the past, sometimes to devastating effect, and continue to do so today. Collisions with NEOs large enough to do significant damage to the ground are fortunately infrequent, but such events can occur at any time and we therefore need to develop and validate the techniques and technologies necessary to prevent the Earth impact of an incoming NEO. In this paper we provide background on the hazard posed to Earth by NEOs and present the results of a recent study performed by the NASA/Goddard Space Flight Center's Mission Design Lab (MDL) in collaboration with Iowa State University's Asteroid Deflection Research Center (ADRC) to design a flight validation mission for a Hypervelocity Asteroid Intercept Vehicle (HAIV) as part of a Phase 2 NASA Innovative Advanced Concepts (NIAC) research project. The HAIV is a two-body vehicle consisting of a leading kinetic impactor and trailing follower carrying a Nuclear Explosive Device (NED) payload. The HAIV detonates the NED inside the crater in the NEO's surface created by the lead kinetic impactor portion of the vehicle, effecting a powerful subsurface detonation to disrupt the NEO. For the flight validation mission, only a simple mass proxy for the NED is carried in the HAIV. Ongoing and future research topics are discussed following the presentation of the detailed flight validation mission design results produced in the MDL.

Barbee, Brent W.; Wie, Bong; Steiner, Mark; Getzandanner, Kenneth

2015-01-01

296

Multidisciplinary Design Optimization of a Full Vehicle with High Performance Computing  

NASA Technical Reports Server (NTRS)

Multidisciplinary design optimization (MDO) of a full vehicle under the constraints of crashworthiness, NVH (Noise, Vibration and Harshness), durability, and other performance attributes is one of the imperative goals for automotive industry. However, it is often infeasible due to the lack of computational resources, robust simulation capabilities, and efficient optimization methodologies. This paper intends to move closer towards that goal by using parallel computers for the intensive computation and combining different approximations for dissimilar analyses in the MDO process. The MDO process presented in this paper is an extension of the previous work reported by Sobieski et al. In addition to the roof crush, two full vehicle crash modes are added: full frontal impact and 50% frontal offset crash. Instead of using an adaptive polynomial response surface method, this paper employs a DOE/RSM method for exploring the design space and constructing highly nonlinear crash functions. Two NMO strategies are used and results are compared. This paper demonstrates that with high performance computing, a conventionally intractable real world full vehicle multidisciplinary optimization problem considering all performance attributes with large number of design variables become feasible.

Yang, R. J.; Gu, L.; Tho, C. H.; Sobieszczanski-Sobieski, Jaroslaw

2001-01-01

297

Applying Monte Carlo Simulation to Launch Vehicle Design and Requirements Analysis  

NASA Technical Reports Server (NTRS)

This Technical Publication (TP) is meant to address a number of topics related to the application of Monte Carlo simulation to launch vehicle design and requirements analysis. Although the focus is on a launch vehicle application, the methods may be applied to other complex systems as well. The TP is organized so that all the important topics are covered in the main text, and detailed derivations are in the appendices. The TP first introduces Monte Carlo simulation and the major topics to be discussed, including discussion of the input distributions for Monte Carlo runs, testing the simulation, how many runs are necessary for verification of requirements, what to do if results are desired for events that happen only rarely, and postprocessing, including analyzing any failed runs, examples of useful output products, and statistical information for generating desired results from the output data. Topics in the appendices include some tables for requirements verification, derivation of the number of runs required and generation of output probabilistic data with consumer risk included, derivation of launch vehicle models to include possible variations of assembled vehicles, minimization of a consumable to achieve a two-dimensional statistical result, recontact probability during staging, ensuring duplicated Monte Carlo random variations, and importance sampling.

Hanson, J. M.; Beard, B. B.

2010-01-01

298

Integration of Launch Vehicle Simulation/Analysis Tools and Lunar Cargo Lander Design. Part 1/2  

NASA Technical Reports Server (NTRS)

Simulation and analysis of vehicle performance is essential for design of a new launch vehicle system. It is more and more demand to have an integrated, highly efficient, robust simulation tool with graphical user interface (GUI) for vehicle performance and simulations. The objectives of this project are to integrate and develop launch vehicle simulation and analysis tools in MATLAB/Simulink under PC Platform, to develop a vehicle capable of being launched on a Delta-IV Heavy Launch Vehicle which can land on the moon with the goal of pre-implanting cargo for a new lunar mission, also with the capability of selecting other launch vehicles that are capable of inserting a payload into Trans-Lunar Injection (TLI). The vehicle flight simulation software, MAVERIC-II (Marshall Aerospace VEhicle Representation In 'C'), developed by Marshall Space Flight Center was selected as a starting point for integration of simulation/analysis tools. The goals are to convert MAVERIC-II from UNIX to PC platform and build input/output GUI s in the MATLAB environment, and then integrate them under MATLAB/Simulink with other modules. Currently, MAVERIC-II has been successfully converted from UNIX to PC using Microsoft Services for UNIX subsystem on PC. Input/Output GUI's have been done for some key input/output files. Calling MAVERIC-II from Simulink has been tested. Details regarding Lunar Cargo Lander Design are described in Part 2/2 of the paper on page X-1.

Shiue, Yeu-Sheng Paul

2005-01-01

299

Overview of the Integrated Programs for Aerospace Vehicle Design (IPAD) project  

NASA Technical Reports Server (NTRS)

To respond to national needs for improved productivity in engineering design and manufacturing, a NASA supported joint industry/government project is underway denoted Integrated Programs for Aerospace Vehicle Design (IPAD). The objective is to improve engineering productivity through better use of computer technology. It focuses on development of data base management technology and associated software for integrated company wide management of engineering and manufacturing information. Results to date on the IPAD project include an in depth documentation of a representative design process for a large engineering project, the definition and design of computer aided design software needed to support that process, and the release of prototype software to manage engineering information. This paper provides an overview of the IPAD project and summarizes progress to date and future plans.

Venneri, S. L.

1983-01-01

300

Designing cathodic protection systems for marine structures and vehicles. ASTM special technical publication 1370  

SciTech Connect

Cathodic protection is an important method of protecting structures and ships from the corrosive effects of seawater. Poor designs can be far more costly to implement than optimal designs, Improper design can cause overprotection, with resulting paint blistering and accelerated corrosion of some alloys, underprotection, with resultant structure corrosion, or stray current corrosion of nearby structures. The first ASTM symposium specifically aimed at cathodic protection in seawater was intended to compile all the criteria and philosophy for designing both sacrificial and impressed current cathodic protection systems for structures and vehicles in seawater. The papers which are included in this STP are significant in that they summarize the major seawater cathodic protection system design philosophies. Papers have been processed separately for inclusion on the database.

Hack, H.P. [ed.

1999-07-01

301

A Design Comparison of Atmospheric Flight Vehicles for the Exploration of Titan  

NASA Technical Reports Server (NTRS)

Titan, the largest moon of Saturn, is one of the most scientifically interesting locations in the Solar System. With a very cold atmosphere that is five times as dense as Earth s, and one and a half times the surface pressure, it also provides one of the most aeronautically fascinating environments known to humankind. While this may seem the ideal place to attempt atmospheric flight, many challenges await any vehicle attempting to navigate through it. In addition to these physical challenges, any scientific exploration mission to Titan will most likely have several operational constraints. One difficult constraint is the desire for a global survey of the planet and thus, a long duration flight within the atmosphere. Since many of the scientific measurements that would be unique to a vehicle flying through the atmosphere (as opposed to an orbiting spacecraft) desire near-surface positioning of their associated instruments, the vehicle must also be able to fly within the first scale height of the atmosphere. Another difficult constraint is that interaction with the surface, whether by landing or dropped probe, is also highly desirable from a scientific perspective. Two common atmospheric flight platforms that might be used for this mission are the airplane and airship. Under the assumption of a mission architecture that would involve an orbiting relay spacecraft delivered via aerocapture and an atmospheric flight vehicle delivered via direct entry, designs were developed for both platforms that are unique to Titan. Consequently, after a viable design was achieved for each platform, their advantages and disadvantages were compared. This comparison included such factors as deployment risk, surface interaction capability, mass, and design heritage. When considering all factors, the preferred candidate platform for a global survey of Titan is an airship.

Gasbarre, Joseph F.; Wright, Henry S.; Lewis, Mark J.

2005-01-01

302

Cryogenic gear technology for an orbital transfer vehicle engine and tester design  

NASA Technical Reports Server (NTRS)

Technology available for gears used in advanced Orbital Transfer Vehicle rocket engines and the design of a cryogenic adapted tester used for evaluating advanced gears are presented. The only high-speed, unlubricated gears currently in cryogenic service are used in the RL10 rocket engine turbomachinery. Advanced rocket engine gear systems experience operational load conditions and rotational speed that are beyond current experience levels. The work under this task consisted of a technology assessment and requirements definition followed by design of a self-contained portable cryogenic adapted gear test rig system.

Calandra, M.; Duncan, G.

1986-01-01

303

Development and application of ride-quality criteria. [considering vehicle vibration damping design  

NASA Technical Reports Server (NTRS)

Ride quality vibration criteria applicable to the design and evaluation of air and surface transportation systems are described. Consideration is given to the magnitude of vehicle vibration experienced by the passenger, the frequency of vibration, the direction of vibration measurements are presented for a variety of air and surface transportation systems. In addition, simulator data on seat dynamics and passenger response are presented. Results suggest the relative merits of various physical descriptors and measurement locations for characterizing the vibration in terms suitable for the design and/or evaluation of transportation systems.

Stephens, D. G.

1974-01-01

304

An omni-directional design tool for series hybrid electric vehicle design  

E-print Network

ratings of these components, are discussed below. A detailed derivation of these equations involves study of vehicle dynamics [6], electric motors and power converters [7], ICE modeling [8], battery model [9] and others... scenario ........................... 79 36 a)Drive cycle b)motor power versus time c) engine power versus time d) battery power versus time e) battery energy level versus time.................... 80 37 Two dimensional plots for the first...

Shidore, Neeraj Shripad

2005-02-17

305

The design and results of an algorithm for intelligent ground vehicles  

NASA Astrophysics Data System (ADS)

This paper addresses the design, design method, test platform, and test results of an algorithm used in autonomous navigation for intelligent vehicles. The Bluefield State College (BSC) team created this algorithm for its 2009 Intelligent Ground Vehicle Competition (IGVC) robot called Anassa V. The BSC robotics team is comprised of undergraduate computer science, engineering technology, marketing students, and one robotics faculty advisor. The team has participated in IGVC since the year 2000. A major part of the design process that the BSC team uses each year for IGVC is a fully documented "Post-IGVC Analysis." Over the nine years since 2000, the lessons the students learned from these analyses have resulted in an ever-improving, highly successful autonomous algorithm. The algorithm employed in Anassa V is a culmination of past successes and new ideas, resulting in Anassa V earning several excellent IGVC 2009 performance awards, including third place overall. The paper will discuss all aspects of the design of this autonomous robotic system, beginning with the design process and ending with test results for both simulation and real environments.

Duncan, Matthew; Milam, Justin; Tote, Caleb; Riggins, Robert N.

2010-01-01

306

Design for implementation : fully integrated charging & docking infrastructure used in Mobility-on-Demand electric vehicle fleets  

E-print Network

As the technology used in electric vehicles continues to advance, there is an increased demand for urban-appropriate electric charging stations emphasizing a modern user interface, robust design, and reliable functionality. ...

Martin, Jean Mario Nations

2012-01-01

307

Design and analysis of aluminum/air battery system for electric vehicles  

NASA Astrophysics Data System (ADS)

Aluminum (Al)/air batteries have the potential to be used to produce power to operate cars and other vehicles. These batteries might be important on a long-term interim basis as the world passes through the transition from gasoline cars to hydrogen fuel cell cars. The Al/air battery system can generate enough energy and power for driving ranges and acceleration similar to gasoline powered cars. From our design analysis, it can be seen that the cost of aluminum as an anode can be as low as US 1.1/kg as long as the reaction product is recycled. The total fuel efficiency during the cycle process in Al/air electric vehicles (EVs) can be 15% (present stage) or 20% (projected) comparable to that of internal combustion engine vehicles (ICEs) (13%). The design battery energy density is 1300 Wh/kg (present) or 2000 Wh/kg (projected). The cost of battery system chosen to evaluate is US 30/kW (present) or US$ 29/kW (projected). Al/air EVs life-cycle analysis was conducted and compared to lead/acid and nickel metal hydride (NiMH) EVs. Only the Al/air EVs can be projected to have a travel range comparable to ICEs. From this analysis, Al/air EVs are the most promising candidates compared to ICEs in terms of travel range, purchase price, fuel cost, and life-cycle cost.

Yang, Shaohua; Knickle, Harold

308

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

NASA Technical Reports Server (NTRS)

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.

1990-01-01

309

Aerospace Meteorology Lessons Learned Relative to Aerospace Vehicle Design and Operations  

NASA Technical Reports Server (NTRS)

Aerospace Meteorology came into being in the 1950s as the development of rockets for military and civilian usage grew in the United States. The term was coined to identify those involved in the development of natural environment models, design/operational requirements, and environment measurement systems to support the needs of aerospace vehicles, both launch vehicles and spacecraft. It encompassed the atmospheric environment of the Earth, including Earth orbit environments. Several groups within the United States were active in this area, including the Department of Defense, National Aeronautics and Space Administration, and a few of the aerospace industry groups. Some aerospace meteorology efforts were similar to those being undertaken relative to aviation interests. As part of the aerospace meteorology activities a number of lessons learned resulted that produced follow on efforts which benefited from these experiences, thus leading to the rather efficient and technologically current descriptions of terrestrial environment design requirements, prelaunch monitoring systems, and forecast capabilities available to support the development and operations of aerospace vehicles.

Vaughan, William W.; Anderson, B. Jeffrey

2004-01-01

310

Design of a data-driven predictive controller for start-up process of AMT vehicles.  

PubMed

In this paper, a data-driven predictive controller is designed for the start-up process of vehicles with automated manual transmissions (AMTs). It is obtained directly from the input-output data of a driveline simulation model constructed by the commercial software AMESim. In order to obtain offset-free control for the reference input, the predictor equation is gained with incremental inputs and outputs. Because of the physical characteristics, the input and output constraints are considered explicitly in the problem formulation. The contradictory requirements of less friction losses and less driveline shock are included in the objective function. The designed controller is tested under nominal conditions and changed conditions. The simulation results show that, during the start-up process, the AMT clutch with the proposed controller works very well, and the process meets the control objectives: fast clutch lockup time, small friction losses, and the preservation of driver comfort, i.e., smooth acceleration of the vehicle. At the same time, the closed-loop system has the ability to reject uncertainties, such as the vehicle mass and road grade. PMID:21954207

Lu, Xiaohui; Chen, Hong; Wang, Ping; Gao, Bingzhao

2011-12-01

311

Mach 6.5 air induction system design for the Beta 2 two-stage-to-orbit booster vehicle  

NASA Technical Reports Server (NTRS)

A preliminary, two-dimensional, mixed compression air induction system is designed for the Beta II Two Stage to Orbit booster vehicle to minimize installation losses and efficiently deliver the required airflow. Design concepts, such as an external isentropic compression ramp and a bypass system were developed and evaluated for performance benefits. The design was optimized by maximizing installed propulsion/vehicle system performance. The resulting system design operating characteristics and performance are presented. The air induction system design has significantly lower transonic drag than similar designs and only requires about 1/3 of the bleed extraction. In addition, the design efficiently provides the integrated system required airflow, while maintaining adequate levels of total pressure recovery. The excellent performance of this highly integrated air induction system is essential for the successful completion of the Beta II booster vehicle mission.

Midea, Anthony C.

1991-01-01

312

Mach 6.5 air induction system design for the Beta II Two-Stage-to-Orbit booster vehicle  

NASA Technical Reports Server (NTRS)

A preliminary, two-dimensional, mixed compression air induction system is designed for the Beta II Two-Stage-to-Orbit booster vehicle to minimize installation losses and efficiently deliver the required airflow. Design concepts, such as an external isentropic compression ramp and a bypass system, are developed and evaluated for performance benefits. The design is optimized by maximizing installed propulsion/vehicle system performance, and the resulting system design operating characteristics and performance are presented. The air induction system design has significantly lower transonic drag than similar designs, and only requires approximately 1/3 of the bleed extraction. In addition, the design efficiently provides the integrated system required airflow, while maintaining adequate levels of total pressure recovery. The excellent performance of this highly integrated air induction system is essential for the successful completion of the Beta II booster vehicle mission.

Midea, Anthony C.

1991-01-01

313

Studies on thermal protection system for capsule type re-entry vehicle - Computer aided TPS design method  

Microsoft Academic Search

A computer-aided conceptual design method to determine the optimum TPS for a capsule-type reentry vehicle was investigated aerodynamically and aerothermodynamically. This method aims at the effective and rapid design at the conceptual stage, and consequently graphical optimization procedures were adopted using a computer-generated data bank consisting of aerodynamic and aerothermodynamic characteristics of capsule-type vehicles, atmospheric trajectories, thermal properties of TPS,

S. Nomura; Y. Yamamoto; M. Watanabe

1984-01-01

314

Design of an autonomous teleoperated cargo transporting vehicle for lunar base operations  

NASA Technical Reports Server (NTRS)

At the turn of the century NASA plans to begin construction of a lunar base. The base will likely consist of developed areas (i.e., habitation, laboratory, landing and launching sites, power plant) separated from each other due to safety considerations. The Self-Repositioning Track Vehicle (SRTV) was designed to transport cargo between these base facilities. The SRTV operates by using two robotic arms to raise and position segments of track upon which the vehicle travels. The SRTV utilizes the semiautonomous mobility (SAM) method of teleoperation; actuator-controlled interlocking track sections; two robotic arms each with five degrees of freedom; and these materials: titanium for structural members and aluminum for shell members, with the possible use of light-weight, high-strength composites.

Holt, James; Lao, Tom; Monali, Nkoy

1989-01-01

315

Aerothermodynamic design feasibility of a generic planetary aerocapture/aeromaneuver vehicle  

NASA Technical Reports Server (NTRS)

Lifting aerodynamic configurations have been screened and selected for a generic planetary aerocapture/aeromaneuver vehicle where a common configuration will be utilized for missions to any of several planets including Mars, Saturn and Uranus. Hypersonic convective and radiative heat transfer to these vehicles was estimated based on a combination of three-dimensional inviscid and viscous flow field solutions and from engineering correlations developed for the numerous complete convective and radiative heat transfer evaluations in CO2 and H2-He mixtures from the Pioneer Venus and Galileo programs. Thermal protection materials have been selected and sized. It is recommended that the thermal protection system be designed for each specific mission, thus maximizing the deliverable payload. Aerothermodynamic technology needs of this generic aerocapture concept are identified.

Florence, D. E.

1981-01-01

316

Design and vibration control of military vehicle suspension system using magnetorheological damper and disc spring  

NASA Astrophysics Data System (ADS)

This paper proposes a new type of magnetorheological (MR) fluid based suspension system and applies it to military vehicles for vibration control. The suspension system consists of a gas spring, a MR damper and a safety passive damper (disc spring). Firstly, a dynamic model of the MR damper is derived by considering the pressure drop due to the viscosity and the yield stress of the MR fluid. A dynamic model of the disc spring is then established for its evaluation as a safety damper with respect to load and pressure. Secondly, a full military vehicle is adopted for the integration of the MR suspension system. A skyhook controller associated with a semi-active actuating condition is then designed to reduce the imposed vibration. In order to demonstrate the effectiveness of the proposed MR suspension system, a computer simulation is undertaken showing the vibration control performance of such properties as vertical displacement and pitch angle, evaluated for a bumpy road profile.

Ha, Sung Hoon; Seong, Min-Sang; Choi, Seung-Bok

2013-06-01

317

Preliminary Assessment of Artificial Gravity Impacts to Deep-Space Vehicle Design  

NASA Technical Reports Server (NTRS)

Even after more than thirty years of scientific investigation, serious concerns regarding human physiological effects of long-duration microgravity exposure remain. These include loss of bone mineral density, skeletal muscle atrophy, and orthostatic hypertension, among others. In particular, "Safe Passage: Astronaut Care for Exploration Missions," states "loss of bone density, which apparently occurs at a rate of 1% per month in microgravity, is relatively manageable on the short-duration missions of the space shuttle, but it becomes problematic on the ISS [International Space Station]. ...If this loss is not mitigated, interplanetary missions will be impossible." While extensive investigations into potential countermeasures are planned on the ISS, the delay in attaining full crew complement and onboard facilities, and the potential for extending crews tours of duty threaten the timely (< 20 years!) accumulation of sufficient data for countermeasures formulation. Indeed, there is no guarantee that even with the data, a practical or sufficiently robust set of countermeasures will be forthcoming. Providing an artificial gravity (AG) environment by crew centrifugation aboard deep-space human exploration vehicles, long a staple technique of science fiction, has received surprisingly limited engineering assessment. This is most likely due to a number of factors: the lack of definitive design requirements, especially acceptable artificial gravity levels and rotation rates, the perception of high vehicle mass and performance penalties, the incompatibility of resulting vehicle configurations with space propulsion options (i.e., aerocapture), the perception of complications associated with de-spun components such as antennae and photovoltaic arrays, and the expectation of effective crew micro-gravity countermeasures. These perception and concerns may have been overstated, or may be acceptable alternatives to countermeasures of limited efficacy. This study was undertaken as an initial step to try to understand the implications of and potential solutions to incorporating artificial gravity in the design of human deep-space exploration vehicles. Of prime interest will be the mass penalties incurred by incorporating AG, along with any mission performance degradation.

Joosten, B. Kent

2007-01-01

318

DUKSUP: A Computer Program for High Thrust Launch Vehicle Trajectory Design and Optimization  

NASA Technical Reports Server (NTRS)

From the late 1960's through 1997, the leadership of NASA's Intermediate and Large class unmanned expendable launch vehicle projects resided at the NASA Lewis (now Glenn) Research Center (LeRC). One of LeRC's primary responsibilities --- trajectory design and performance analysis --- was accomplished by an internally-developed analytic three dimensional computer program called DUKSUP. Because of its Calculus of Variations-based optimization routine, this code was generally more capable of finding optimal solutions than its contemporaries. A derivation of optimal control using the Calculus of Variations is summarized including transversality, intermediate, and final conditions. The two point boundary value problem is explained. A brief summary of the code's operation is provided, including iteration via the Newton-Raphson scheme and integration of variational and motion equations via a 4th order Runge-Kutta scheme. Main subroutines are discussed. The history of the LeRC trajectory design efforts in the early 1960's is explained within the context of supporting the Centaur upper stage program. How the code was constructed based on the operation of the Atlas/Centaur launch vehicle, the limits of the computers of that era, the limits of the computer programming languages, and the missions it supported are discussed. The vehicles DUKSUP supported (Atlas/Centaur, Titan/Centaur, and Shuttle/Centaur) are briefly described. The types of missions, including Earth orbital and interplanetary, are described. The roles of flight constraints and their impact on launch operations are detailed (such as jettisoning hardware on heating, Range Safety, ground station tracking, and elliptical parking orbits). The computer main frames on which the code was hosted are described. The applications of the code are detailed, including independent check of contractor analysis, benchmarking, leading edge analysis, and vehicle performance improvement assessments. Several of DUKSUP's many major impacts on launches are discussed including Intelsat, Voyager, Pioneer Venus, HEAO, Galileo, and Cassini.

Williams, C. H.; Spurlock, O. F.

2014-01-01

319

Ares I Crew Launch Vehicle Project: Forward Plan to Preliminary Design Review  

NASA Technical Reports Server (NTRS)

The Exploration Launch Projects Office, located at NASA's Marshall Space Flight Center, conducted the Ares I Crew Launch Vehicle System Requirements Review (SRR) at the end of 2006, a mere year after the project team was assembled. In Ares' first year, extensive trade studies and evaluations were conducted to refine the design initially recommended by the Exploration Systems Architecture Study, conceptual designs were analyzed for fitness, and the contractual framework was assembled to enable a development effort unparalleled in American space flight since the Space Shuttle. Now, the project turns its focus to the Preliminary Design Review (PDR), scheduled for 2008. Taking into consideration the findings of the SRR, the design of the Ares I is being tightened and refined to meet the operability, reliability, and affordability goals outlined by the Constellation Program. As directed in NASA Procedure and Regulation (NPR) 7123, NASA Systems Engineering Procedural Requirements, the Ares I SRR examined "the functional and performance requirements defined for the system and the preliminary program or project plan and ensures that the requirements and the selected concept will satisfy the mission." The SRR was conducted to ensure the system- and element-level design and interface requirements are defined prior to proceeding into the project's design phase. The Exploration Launch Projects Control Board convened on December 19,2006, and accepted the findings of the SRR and the go-forward plan proceeding to PDR. Based upon these findings, the Ares project believes that operability must drive the vehicle's design, and that a number of design challenges, including system mass and reliability, must be addressed as part of the progress to PDR.

Dumbacher, Daniel L.; Reuter, James L.

2007-01-01

320

Aeroassisted manned transfer vehicle (TAXI) for advanced Mars Transportation: NASA/USRA 1987 Senior Design Project  

NASA Technical Reports Server (NTRS)

A conceptual design study of an aeroassisted orbital transfer vehicle is discussed. Nicknamed TAXI, it will ferry personnel and cargo: (1) between low Earth orbit and a spacecraft circling around the Sun in permanent orbit intersecting gravitational fields of Earth and Mars, and (2) between the cycling spacecraft and a Mars orbiting station, co-orbiting with Phobos. Crew safety and mission flexibility (in terms of ability to provide a wide range of delta-V) were given high priority. Three versions were considered, using the same overall configuration based on a low L/D aerobrake with the geometry of a raked off elliptical cone with ellipsoidal nose and a toroidal skirt. The propulsion system consists of three gimballed LOX/LH2 engines firing away from the aerobrake. The versions differ mainly in the size of the aeroshields and propellant tanks. TAXI A version resulted from an initial effort to design a single transfer vehicle able to meet all delta-V requirements during the 15-year period (2025 to 2040) of Mars mission operations. TAXI B is designed to function with the cycling spacecraft moving in a simplified, nominal trajectory. On Mars missions, TAXI B would be able to meet the requirements of all the missions with a relative approach velocity near Mars of less than 9.3 km/sec. Finally, TAXI C is a revision of TAXI A, a transfer vehicle designed for missions with a relative velocity near Mars larger than 9.3 km/sec. All versions carry a crew of 9 (11 with modifications) and a cargo of 10000 lbm. Trip duration varies from 1 day for transfer from LEO to the cycling ship to nearly 5 days for transfer from the ship to the Phobos orbit.

1987-01-01

321

Estimation of payload loads using rigid body interface accelerations. [in structural design of launch vehicle systems  

NASA Technical Reports Server (NTRS)

In the design/analysis process of a payload structural system, the accelerations at the payload/launch vehicle interface obtained from a system analysis using a rigid payload are often used as the input forcing function to the elastic payload to obtain structural design loads. Such an analysis is at best an approximation since the elastic coupling effects are neglected. This paper develops a method wherein the launch vehicle/rigid payload interface accelerations are modified to account for the payload elasticity. The advantage of the proposed method, which is exact to the extent that the physical system can be described by a truncated set of generalized coordinates, is that the complete design/analysis process can be performed within the organization responsible for the payload design. The method requires the updating of the system normal modes to account for payload changes, but does not require a complete transient solution using the composite system model. An application to a real complex structure, the Viking Spacecraft System, is given.

Chen, J. C.; Garba, J. A.; Wada, B. K.

1978-01-01

322

Human Exploration Using Real-Time Robotic Operations (HERRO)- Crew Telerobotic Control Vehicle (CTCV) Design  

NASA Technical Reports Server (NTRS)

The HERRO concept allows real time investigation of planets and small bodies by sending astronauts to orbit these targets and telerobotically explore them using robotic systems. Several targets have been put forward by past studies including Mars, Venus, and near Earth asteroids. A conceptual design study was funded by the NASA Innovation Fund to explore what the HERRO concept and it's vehicles would look like and what technological challenges need to be met. This design study chose Mars as the target destination. In this way the HERRO studies can define the endpoint design concepts for an all-up telerobotic exploration of the number one target of interest Mars. This endpoint design will serve to help planners define combined precursor telerobotics science missions and technology development flights. A suggested set of these technologies and demonstrator missions is shown in Appendix B. The HERRO concept includes a crewed telerobotics orbit vehicle as well three Truck rovers, each supporting two teleoperated geologist robots Rockhounds (each truck/Rockhounds set is landed using a commercially launched aeroshell landing system.) Options include a sample ascent system teamed with an orbital telerobotic sample rendezvous and return spacecraft (S/C) (yet to be designed). Each truck rover would be landed in a science location with the ability to traverse a 100 km diameter area, carrying the Rockhounds to 100 m diameter science areas for several week science activities. The truck is not only responsible for transporting the Rockhounds to science areas, but also for relaying telecontrol and high-res communications to/from the Rockhound and powering/heating the Rockhound during the non-science times (including night-time). The Rockhounds take the place of human geologists by providing an agile robotic platform with real-time telerobotics control to the Rockhound from the crew telerobotics orbiter. The designs of the Truck rovers and Rockhounds will be described in other publications. This document focuses on the CTCV design.

Oleson, Steven R.; McGuire, Melissa L.; Burke, Laura; Chato, David; Fincannon, James; Landis, Geoff; Sandifer, Carl; Warner, Joe; Williams, Glenn; Colozza, Tony; Fittje, Jim; Martini, Mike; Packard, Tom; McCurdy, Dave; Gyekenyesi, John

2010-01-01

323

Kandler Smith, NREL EDV Battery Robust Design -1 Design of Electric Drive Vehicle  

E-print Network

#12;Kandler Smith, NREL EDV Battery Robust Design - 4 Li+ V Typical Structure of Li-ion Batteries V EDV Battery Robust Design - 5 Performance Life Cost Safety Requirements Multi-Scale Physics in Li-ion Outline Aging mechanisms in Li-ion batteries Aging models based on accelerated testing Robust design

324

High-Alpha Research Vehicle (HARV) longitudinal controller: Design, analyses, and simulation resultss  

NASA Technical Reports Server (NTRS)

This paper describes the design, analysis, and nonlinear simulation results (batch and piloted) for a longitudinal controller which is scheduled to be flight-tested on the High-Alpha Research Vehicle (HARV). The HARV is an F-18 airplane modified for and equipped with multi-axis thrust vectoring. The paper includes a description of the facilities, a detailed review of the feedback controller design, linear analysis results of the feedback controller, a description of the feed-forward controller design, nonlinear batch simulation results, and piloted simulation results. Batch simulation results include maximum pitch stick agility responses, angle of attack alpha captures, and alpha regulation for full lateral stick rolls at several alpha's. Piloted simulation results include task descriptions for several types of maneuvers, task guidelines, the corresponding Cooper-Harper ratings from three test pilots, and some pilot comments. The ratings show that desirable criteria are achieved for almost all of the piloted simulation tasks.

Ostroff, Aaron J.; Hoffler, Keith D.; Proffitt, Melissa S.; Brown, Philip W.; Phillips, Michael R.; Rivers, Robert A.; Messina, Michael D.; Carzoo, Susan W.; Bacon, Barton J.; Foster, John F.

1994-01-01

325

Weight and volume estimates for aluminum-air batteries designed for electric vehicle applications  

NASA Astrophysics Data System (ADS)

The weights and volumes of reactants, electrolyte, and hardware components are estimated for an aluminum-air battery designed for a 40-kW (peak), 70-kWh aluminum-air battery. Generalized equations are derived which express battery power and energy content as functions of total anode area, aluminum-anode weight, and discharge current density. Equations are also presented which express total battery weight and volume as linear combinations of the variables, anode area and anode weight. The sizing and placement of battery components within the engine compartment of typical five-passenger vehicles is briefly discussed.

Cooper, J. F.

1980-01-01

326

The design and performance estimates for the propulsion module for the booster of a TSTO vehicle  

NASA Technical Reports Server (NTRS)

A NASA study of the propulsion systems for possible low-risk replacements for the Space Shuttle is presented. Results of preliminary studies to define the USAF two-stage-to-orbit (TSTO) concept to deliver 10,000 pounds to low polar orbit are described. The booster engine module consists of an over/under turbine bypass engines/ramjet engine design for acceleration from takeoff to the staging point of Mach 6.5 and approximately 100,000 feet altitude. Propulsion system performance and weight are presented with preliminary mission study results of vehicle size.

Snyder, Christopher A.; Maldonado, Jaime J.

1991-01-01

327

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

NASA Technical Reports Server (NTRS)

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

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

1993-01-01

328

Autonomous controller design for unmanned aerial vehicles using multi-objective genetic programming  

E-print Network

Abstract. Autonomous navigation controllers were developed for fixed wing unmanned aerial vehicle (UAV) applications using multi-objective genetic programming (GP). Four fitness functions derived from flight simulations were designed and multi-objective GP was used to evolve controllers able to locate a radar source, navigate the UAV to the source efficiently using on-board sensor measurements, and circle around the emitter. Controllers were evolved for three different kinds of radars: stationary, continuously emitting radars, stationary, intermittently emitting radars, and mobile, continuously emitting radars. In this study, realistic flight parameters and sensor inputs were selected to aid in the transference of evolved controllers to physical UAVs. 1

Gregory J. Barlow

2004-01-01

329

PM Motor Parametric Design Analyses for Hybrid Electric Vehicle Traction Drive Application: Interim Report  

SciTech Connect

The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies has a strong interest in making rapid progress in permanent magnet (PM) machine development. The program is directing various technology development projects that will advance the technology and lead to request for proposals (RFP) for manufacturer prototypes. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models to determine the effects of design parameters, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This interim progress report summarizes the results of these activities as of June 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory, Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets. The selection of the IPM machine reflects industry's confidence in this market-proven design that exhibits a power density surpassed by no other machine design.

Staunton, R.H.

2004-08-11

330

Hybrid Vehicle Turbine Engine Technology Support (HVTE-TS) ceramic design manual  

SciTech Connect

This ceramic component design manual was an element of the Advanced Turbine Technology Applications Project (ATTAP). The ATTAP was intended to advance the technological readiness of the ceramic automotive gas turbine engine as a primary power plant. Of the several technologies requiring development before such an engine could become a commercial reality, structural ceramic components represented the greatest technical challenge, and was the prime focus of the program. HVTE-TS, which was created to support the Hybrid Electric Vehicle (HEV) program, continued the efforts begun in ATTAP to develop ceramic components for an automotive gas turbine engine. In HVTE-TS, the program focus was extended to make this technology applicable to the automotive gas turbine engines that form the basis of hybrid automotive propulsion systems consisting of combined batteries, electric drives, and on-board power generators as well as a primary power source. The purpose of the ceramic design manual is to document the process by which ceramic components are designed, analyzed, fabricated, assembled, and tested in a gas turbine engine. Interaction with ceramic component vendors is also emphasized. The main elements of the ceramic design manual are: an overview of design methodology; design process for the AGT-5 ceramic gasifier turbine rotor; and references. Some reference also is made to the design of turbine static structure components to show methods of attaching static hot section ceramic components to supporting metallic structures.

NONE

1997-10-01

331

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

NASA Technical Reports Server (NTRS)

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.

Takashima, N.; Kothari, A. P.

1998-01-01

332

Design of a nonlinear robust controller for a complete unmanned aerial vehicle mission  

NASA Astrophysics Data System (ADS)

Unmanned Aerial Vehicle (UAV) flight control systems must be capable of delivering the required performance while handling nonlinearities and uncertainties in the vehicle model, the atmosphere, and ambient wind. These factors necessitate the development of nonlinear flight control system design methods that can handle large nonlinearities and uncertainties. Variable approaches to the linear control of UAVs have been discussed in the recent literature. However, the development of a nonlinear robust autopilot has not been addressed to any significant degree. The development of a nonlinear autopilot based on robust control methods will be discussed in this dissertation. In this design technique, the nonlinear UAV model is not linearized. The control law is designed using the Hinfinity technique. This dissertation presents the results of an exploratory study to examine robust autopilot nonlinear design methods for the UAV and compare this new approach with existing PID, LQR, and linear Hinfinity techniques. Since the method must then be verified, its flight simulation will be done using MATLAB/SIMULINK. Verification, validation and robustness tests are documented at the end of this dissertation. The airplane examined is called the Hawkeye. It was designed and built by KU students in the fall of 2004. It is a small, 14 foot wingspan, remotely controlled airplane made from composite materials with a maximum takeoff weight of 90 lbs. It will be used in the future as a small UAV for research programs at KU. The mission includes take-off, climb, cruise, a one and a half circle accomplished in a level turn, and a return back to its original airfield accomplished by cruising back, descending, and completing an approach and landing. After take-off, the airplane is required to climb to 1,000 ft altitude, and then it travels 5,000 ft over the ground into the target area. It will then take some photos of that target using its camera. The complete mission for the UAV lasts about 180 seconds.

Sadraey, Mohammad Hashem

333

Human Factors in the Design of the Crew Exploration Vehicle (CEV)  

NASA Technical Reports Server (NTRS)

NASA s Space Exploration vision for humans to venture to the moon and beyond provides interesting human factors opportunities and challenges. The Human Engineering group at NASA has been involved in the initial phases of development of the Crew Exploration Vehicle (CEV), Orion. Getting involved at the ground level, Human Factors engineers are beginning to influence design; this involvement is expected to continue throughout the development lifecycle. The information presented here describes what has been done to date, what is currently going on, and what is expected in the future. During Phase 1, prior to the contract award to Lockheed Martin, the Human Engineering group was involved in generating requirements, conducting preliminary task analyses based on interviews with subject matter experts in all vehicle systems areas, and developing preliminary concepts of operations based on the task analysis results. In addition, some early evaluations to look at CEV net habitable volume were also conducted. The program is currently in Phase 2, which is broken down into design cycles, including System Readiness Review, Preliminary Design Review, and Critical Design Review. Currently, there are ongoing Human Engineering Technical Interchange Meetings being held with both NASA and Lockheed Martin in order to establish processes, desired products, and schedules. Multiple design trades and quick-look evaluations (e.g. display device layout and external window size) are also in progress. Future Human Engineering activities include requirement verification assessments and crew/stakeholder evaluations of increasing fidelity. During actual flights of the CEV, the Human Engineering group is expected to be involved in in-situ testing and lessons learned reporting, in order to benefit human space flight beyond the initial CEV program.

Whitmore, Mihriban; Byrne, Vicky; Holden, Kritina

2007-01-01

334

The Levitation Controller Design of an Electromagnetic Suspension Vehicle using Gain Scheduled Control  

Microsoft Academic Search

Maglev vehicles constitute a new class of transport systems that has been constantly developed and improved to become a new alternative of comfortable and secure transport. These vehicles have suspension, propulsion and guidance systems based on magnetic forces. Electromagnetic suspension vehicle systems are highly nonlinear and essentially unstable systems. Levitation of an electromagnetically levitated vehicle prototype can be accomplished with

Min-Soo Kim; Yeun-Sub Byun; Young-Hoon Lee; Kwan-Sup Lee

2006-01-01

335

Design of overload vehicle monitoring and response system based on DSP  

NASA Astrophysics Data System (ADS)

The overload vehicles are making much more damage to the road surface than the regular ones. Many roads and bridges are equipped with structural health monitoring system (SHM) to provide early-warning to these damage and evaluate the safety of road and bridge. However, because of the complex nature of SHM system, it's expensive to manufacture, difficult to install and not well-suited for the regular bridges and roads. Based on this application background, this paper designs a compact structural health monitoring system based on DSP, which is highly integrated, low-power, easy to install and inexpensive to manufacture. The designed system is made up of sensor arrays, the charge amplifier module, the DSP processing unit, the alarm system for overload, and the estimate for damage of the road and bridge structure. The signals coming from sensor arrays go through the charge amplifier. DSP processing unit will receive the amplified signals, estimate whether it is an overload signal or not, and convert analog variables into digital ones so that they are compatible with the back-end digital circuit for further processing. The system will also restrict certain vehicles that are overweight, by taking image of the car brand, sending the alarm, and transferring the collected pressure data to remote data center for further monitoring analysis by rain-flow counting method.

Yu, Yan; Liu, Yiheng; Zhao, Xuefeng

2014-03-01

336

Hardware-Based Non-Optimum Factors for Launch Vehicle Structural Design  

NASA Technical Reports Server (NTRS)

During aerospace vehicle conceptual and preliminary design, empirical non-optimum factors are typically applied to predicted structural component weights to account for undefined manufacturing and design details. Non-optimum factors are developed here for 32 aluminum-lithium 2195 orthogrid panels comprising the liquid hydrogen tank barrel of the Space Shuttle External Tank using measured panel weights and manufacturing drawings. Minimum values for skin thickness, axial and circumferential blade stiffener thickness and spacing, and overall panel thickness are used to estimate individual panel weights. Panel non-optimum factors computed using a coarse weights model range from 1.21 to 1.77, and a refined weights model (including weld lands and skin and stiffener transition details) yields non-optimum factors of between 1.02 and 1.54. Acreage panels have an average 1.24 non-optimum factor using the coarse model, and 1.03 with the refined version. The observed consistency of these acreage non-optimum factors suggests that relatively simple models can be used to accurately predict large structural component weights for future launch vehicles.

Wu, K. Chauncey; Cerro, Jeffrey A.

2010-01-01

337

Review of uncertainty-based multidisciplinary design optimization methods for aerospace vehicles  

NASA Astrophysics Data System (ADS)

This paper presents a comprehensive review of Uncertainty-Based Multidisciplinary Design Optimization (UMDO) theory and the state of the art in UMDO methods for aerospace vehicles. UMDO has been widely acknowledged as an advanced methodology to address competing objectives of aerospace vehicle design, such as performance, cost, reliability and robustness. However the major challenges of UMDO, namely the computational complexity and organizational complexity caused by both time-consuming disciplinary analysis models and UMDO algorithms, still greatly hamper its application in aerospace engineering. In recent years there is a surge of research in this field aiming at solving these problems. The purpose of this paper is to review these existing approaches systematically, highlight research challenges and opportunities, and help guide future efforts. Firstly, the UMDO theory preliminaries are introduced to clarify the basic UMDO concepts and mathematical formulations, as well as provide a panoramic view of the general UMDO solving process. Then following the UMDO solving process, research progress of each key step is separately surveyed and discussed, specifically including uncertainty modeling, uncertainty propagation and analysis, optimization under uncertainty, and UMDO procedure. Finally some conclusions are given, and future research trends and prospects are discussed.

Yao, Wen; Chen, Xiaoqian; Luo, Wencai; van Tooren, Michel; Guo, Jian

2011-08-01

338

Design of Field Experiments for Adaptive Sampling of the Ocean with Autonomous Vehicles  

NASA Astrophysics Data System (ADS)

Due to the highly non-linear and dynamical nature of oceanic phenomena, the predictive capability of various ocean models depends on the availability of operational data. A practical method to improve the accuracy of the ocean forecast is to use a data assimilation methodology to combine in-situ measured and remotely acquired data with numerical forecast models of the physical environment. Autonomous surface and underwater vehicles with various sensors are economic and efficient tools for exploring and sampling the ocean for data assimilation; however there is an energy limitation to such vehicles, and thus effective resource allocation for adaptive sampling is required to optimize the efficiency of exploration. In this paper, we use physical oceanography forecasts of the coastal zone of Singapore for the design of a set of field experiments to acquire useful data for model calibration and data assimilation. The design process of our experiments relied on the oceanography forecast including the current speed, its gradient, and vorticity in a given region of interest for which permits for field experiments could be obtained and for time intervals that correspond to strong tidal currents. Based on these maps, resources available to our experimental team, including Autonomous Surface Craft (ASC) are allocated so as to capture the oceanic features that result from jets and vortices behind bluff bodies (e.g., islands) in the tidal current. Results are summarized from this resource allocation process and field experiments conducted in January 2009.

Zheng, H.; Ooi, B. H.; Cho, W.; Dao, M. H.; Tkalich, P.; Patrikalakis, N. M.

2010-05-01

339

Studies on thermal protection system for capsule type re-entry vehicle - Computer aided TPS design method  

NASA Astrophysics Data System (ADS)

A computer-aided conceptual design method to determine the optimum TPS for a capsule-type reentry vehicle was investigated aerodynamically and aerothermodynamically. This method aims at the effective and rapid design at the conceptual stage, and consequently graphical optimization procedures were adopted using a computer-generated data bank consisting of aerodynamic and aerothermodynamic characteristics of capsule-type vehicles, atmospheric trajectories, thermal properties of TPS, and so forth. As examples, optimum TPS designs were demonstrated both for reusable alumina tile and for charring ablator under a constrained deceleration rate of less than 2 gs.

Nomura, S.; Yamamoto, Y.; Watanabe, M.

340

The Role of Habitability Studies in Space Facility and Vehicle Design  

NASA Technical Reports Server (NTRS)

This document is a viewgraph presentation which reviews the role of the space architect in designing a space vehicle with habitability as a chief concern. Habitability is composed of the qualities of the environment or system which support the crew in working and living. All the impacts from habitability are interdependent; i.e., impacts to well-being can impact performance, safety or efficiency. After reviewing the issues relating to habitability the presentation discusses the application of these issues in two case studies. The first studies the Bio-Plex Hab chamber which includes designs of the living and working areas. The second case study is the ISS-TransHab which is being studied as a prototype for Mars transit.

Adams, Constance M.

1999-01-01

341

Design and test of a situation-augmented display for an unmanned aerial vehicle monitoring task.  

PubMed

In this study, a situation-augmented display for unmanned aerial vehicle (UAV) monitoring was designed, and its effects on operator performance and mental workload were examined. The display design was augmented with the knowledge that there is an invariant flight trajectory (formed by the relationship between altitude and velocity) for every flight, from takeoff to landing. 56 participants were randomly assigned to the situation-augmented display or a conventional display condition to work on 4 (number of abnormalities) x 2 (noise level) UAV monitoring tasks three times. Results showed that the effects of situation-augmented display on flight completion time and time to detect abnormalities were robust under various workload conditions, but error rate and perceived mental workload were unaffected by the display type. Results suggest that the UAV monitoring task is extremely difficult, and that display devices providing high-level situation-awareness may improve operator monitoring performance. PMID:24422345

Lu, Jen-Li; Horng, Ruey-Yun; Chao, Chin-Jung

2013-08-01

342

Holarchical Systems and Emotional Holons : Biologically-Inspired System Designs for Control of Autonomous Aerial Vehicles  

NASA Technical Reports Server (NTRS)

The BEES (Bio-inspired Engineering for Exploration Systems) for Mars project at NASA Ames Research Center has the goal of developing bio-inspired flight control strategies to enable aerial explorers for Mars scientific investigations. This paper presents a summary of our ongoing research into biologically inspired system designs for control of unmanned autonomous aerial vehicle communities for Mars exploration. First, we present cooperative design considerations for robotic explorers based on the holarchical nature of biological systems and communities. Second, an outline of an architecture for cognitive decision making and control of individual robotic explorers is presented, modeled after the emotional nervous system of cognitive biological systems. Keywords: Holarchy, Biologically Inspired, Emotional UAV Flight Control

Ippolito, Corey; Plice, Laura; Pisanich, Greg

2003-01-01

343

A Development of Design and Control Methodology for Next Generation Parallel Hybrid Electric Vehicle  

E-print Network

. ........................................................... 2? Figure 3. Nissan Leaf? commercially available Electric Vehicle ................................. 4? Figure 4. Total passenger vehicle sales and HEV sales in the U. S. ............................... 5? Figure 5. Prius Plug... to that of conventional vehicles. The main disadvantages the electric vehicles are: limited travel range, long recharge time, and high price. Take Nissan Leaf for example, which is a commercially available Electric Vehicle in the North America automobile market...

Lai, Lin

2013-01-28

344

Nozzle design study for a quasi-axisymmetric scramjet-powered vehicle at Mach 7.9 flight conditions  

NASA Astrophysics Data System (ADS)

A nozzle shape optimization study for a quasi-axisymmetric scramjet has been performed for a Mach 7.9 operating condition with hydrogen fuel, aiming at the application of a hypersonic airbreathing vehicle. In this study, the nozzle geometry which is parameterized by a set of design variables, is optimized for the single objective of maximum net thrust using an in-house CFD solver for inviscid flowfields with a simple force prediction methodology. The combustion is modelled using a simple chemical reaction code. The effects of the nozzle design on the overall vehicle performance are discussed. For the present geometry, net thrust is achieved for the optimized vehicle design. The results of the nozzle-optimization study show that performance is limited by the nozzle area ratio that can be incorporated into the vehicle without leading to too large a base diameter of the vehicle and increasing the external drag of the vehicle. This study indicates that it is very difficult to achieve positive thrust at Mach 7.9 using the basic geometry investigated.

Tanimizu, Katsuyoshi; Mee, David J.; Stalker, Raymond J.; Jacobs, Peter A.

2013-09-01

345

A bi-criterion optimization approach for the design and planning of hydrogen supply chains for vehicle  

E-print Network

friendly and has many potential energy uses, including powering road vehicles and aircrafts, and heatingA bi-criterion optimization approach for the design and planning of hydrogen supply chains the design of hydrogen supply chains for vehi- cle use with economic and environmental concerns. Given a set

Grossmann, Ignacio E.

346

Design and control of a single stator dual PM rotors axial synchronous machine for hybrid electric vehicles  

Microsoft Academic Search

In this paper is presenting the preliminary designing and control of a synchronous machine with axial airgap single stator dual-rotor with permanent surface magnets and different pole pairs number, destined for hybrid electric vehicles (HEV) applications. For machines designing was used the equivalent magnetic circuits method that takes into account the saturation and dispersion of the magnetic field. The control

Lucian Nicolae Tutelea; Sorin Ioan Deaconu; Ion Boldea; Fabrizio Marignetti; Gabriel Nicolae Popa

2011-01-01

347

PM Motor Parametric Design Analyses for a Hybrid Electric Vehicle Traction Drive Application  

SciTech Connect

The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies office has a strong interest in making rapid progress in permanent magnet (PM) machine development. The DOE FreedomCAR program is directing various technology development projects that will advance the technology and hopefully lead to a near-term request for proposals (RFP) for a to-be-determined level of initial production. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This report summarizes the results of these activities as of September 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched-reluctance machines. The FreedomCAR program, while acknowledging the progress made by Oak Ridge National Laboratory (ORNL), Delphi, Delco-Remy International, and others in these programs, has redirected efforts toward a ''short path'' to a marketable and competitive PM motor for hybrid electric vehicle (HEV) traction applications. The program has developed a set of performance targets for the type of traction machine desired. The short-path approach entails a comprehensive design effort focusing on the IPM machine and meeting the performance targets. The selection of the IPM machine reflects industry's confidence in this market-proven design that exhibits a high power density.

Staunton, R.H.

2004-10-11

348

Vehicle design influences whole body vibration exposures: effect of the location of the front axle relative to the cab.  

PubMed

Using a repeated measure design, this study compared differences in whole body vibration (WBV) exposures among 13 drivers who drove a truck with the cab over the front axle (cab-over design) and a truck with the cab situated behind the front axle (non-cab-over design). The drivers drove both trucks over a standardized route that comprised three distinct segments: a freeway segment, a city street segment with stop-and-go driving (traffic lights), and a city street segment without traffic lights. A portable WBV data acquisition system collected tri-axial time-weighted and raw WBV data per ISO 2631-1 and 2631-5 standards. Simultaneous global positioning system (GPS) data were also collected to compare vehicle speeds. The GPS data indicated that there were no speed differences between the two vehicles. However, average and impulsive z-axis vibration levels were significantly higher for the cab-over design than for the non-cab-over design. In addition, significant WBV exposure differences between road types were found, with the freeway segments having the lowest exposures and the city street segments without traffic lights having the highest exposures. Vehicle type and the associated WBV exposures should be considered when purchasing vehicles to be used by full-time professional vehicle operators. PMID:21623531

Blood, Ryan P; Rynell, Patrik W; Johnson, Peter W

2011-06-01

349

Statistical methods for launch vehicle guidance, navigation, and control (GN&C) system design and analysis  

NASA Astrophysics Data System (ADS)

A novel trajectory and attitude control and navigation analysis tool for powered ascent is developed. The tool is capable of rapid trade-space analysis and is designed to ultimately reduce turnaround time for launch vehicle design, mission planning, and redesign work. It is streamlined to quickly determine trajectory and attitude control dispersions, propellant dispersions, orbit insertion dispersions, and navigation errors and their sensitivities to sensor errors, actuator execution uncertainties, and random disturbances. The tool is developed by applying both Monte Carlo and linear covariance analysis techniques to a closed-loop, launch vehicle guidance, navigation, and control (GN&C) system. The nonlinear dynamics and flight GN&C software models of a closed-loop, six-degree-of-freedom (6-DOF), Monte Carlo simulation are formulated and developed. The nominal reference trajectory (NRT) for the proposed lunar ascent trajectory is defined and generated. The Monte Carlo truth models and GN&C algorithms are linearized about the NRT, the linear covariance equations are formulated, and the linear covariance simulation is developed. The performance of the launch vehicle GN&C system is evaluated using both Monte Carlo and linear covariance techniques and their trajectory and attitude control dispersion, propellant dispersion, orbit insertion dispersion, and navigation error results are validated and compared. Statistical results from linear covariance analysis are generally within 10% of Monte Carlo results, and in most cases the differences are less than 5%. This is an excellent result given the many complex nonlinearities that are embedded in the ascent GN&C problem. Moreover, the real value of this tool lies in its speed, where the linear covariance simulation is 1036.62 times faster than the Monte Carlo simulation. Although the application and results presented are for a lunar, single-stage-to-orbit (SSTO), ascent vehicle, the tools, techniques, and mathematical formulations that are discussed are applicable to ascent on Earth or other planets as well as other rocket-powered systems such as sounding rockets and ballistic missiles.

Rose, Michael Benjamin

350

Design and optimization of fuel cell/battery/supercapacitor hybrid power sources for electric vehicles  

NASA Astrophysics Data System (ADS)

Fuel Cell powered Hybrid electric Vehicles (FCHVs) are considered to be the most promising alternatives of Internal Combustion Engines (ICE) vehicles. One of the most important research aspects of FCHVs is their hybrid power sources study; however, current research is insufficient and there are many open problems to be further studied, such as hybrid power sources topology analysis, vehicle power sources design and optimization, and related dynamic models construction. Also a powerful simulation package of FCHVs is indispensable to evaluate and support the related research. Addressing these problems, this dissertation carries out a series of studies step by step which includes the following three parts. The first part is focused on modeling electrochemical components. A novel fully dynamic lithium-ion battery model is developed, which accounts for battery nonlinear equilibrium potentials, rate- and temperature-dependencies, thermal effects and response to transient power demand. A multi-stage resistor capacitor ladder supercapacitor model is constructed with unique characteristics including automatic order selection and capacity scaling. In the modeling of a Proton Exchange Membrane (PEM) fuel cell system, each component is first modeled separately, and then these modules are coupled together into an integrative unit. The second part concentrates on the study of hybrid power source topology analysis. Firstly, the concepts of passive hybrid and active hybrid are defined. Secondly, an active hybrid is constructed and explored through both experiments and simulations. Finally, the comparison of passive and active hybrids, along with battery alone, is undertaken to study the performance extension of power sources using power converters. The study process is further extended and applied in hybrid power source design for FCHVs. In the third part, a complete simulation package for FCHVs is constructed in the Virtual Test Bed (VTB) computational environment. The modeling approach is forward looking (causal) and the system setup is modular, thus the package recognizes the dynamic interaction among different vehicle components and provides a powerful capability to simulate different topologies. After that, a novel 8-step energy component size determination and optimization method is proposed, which is based on the operation of the decreasing rearrangement distribution function of drive cycles.

Gao, Lijun

351

Multidisciplinary Design Technology Development: A Comparative Investigation of Integrated Aerospace Vehicle Design Tools  

NASA Technical Reports Server (NTRS)

This research effort is a joint program between the Departments of Aerospace and Mechanical Engineering and the Computer Science and Engineering Department at the University of Notre Dame. Three Principal Investigators; Drs. Renaud, Brockman and Batill directed this effort. During the four and a half year grant period, six Aerospace and Mechanical Engineering Ph.D. students and one Masters student received full or partial support, while four Computer Science and Engineering Ph.D. students and one Masters student were supported. During each of the summers up to four undergraduate students were involved in related research activities. The purpose of the project was to develop a framework and systematic methodology to facilitate the application of Multidisciplinary Design Optimization (N4DO) to a diverse class of system design problems. For all practical aerospace systems, the design of a systems is a complex sequence of events which integrates the activities of a variety of discipline "experts" and their associated "tools". The development, archiving and exchange of information between these individual experts is central to the design task and it is this information which provides the basis for these experts to make coordinated design decisions (i.e., compromises and trade-offs) - resulting in the final product design. Grant efforts focused on developing and evaluating frameworks for effective design coordination within a MDO environment. Central to these research efforts was the concept that the individual discipline "expert", using the most appropriate "tools" available and the most complete description of the system should be empowered to have the greatest impact on the design decisions and final design. This means that the overall process must be highly interactive and efficiently conducted if the resulting design is to be developed in a manner consistent with cost and time requirements. The methods developed as part of this research effort include; extensions to a sensitivity based Concurrent Subspace Optimization (CSSO) MDO algorithm; the development of a neural network response surface based CSSO-MDO algorithm; and the integration of distributed computing and process scheduling into the MDO environment. This report overviews research efforts in each of these focus. A complete bibliography of research produced with support of this grant is attached.

Renaud, John E.; Batill, Stephen M.; Brockman, Jay B.

1998-01-01

352

Design of a Lunar Quick-Attach Mechanism to Hummer Vehicle Mounting Interface  

NASA Technical Reports Server (NTRS)

This report presents my work experiences while I was an intern with NASA (National Aeronautic and Space Administration) in the Spring of2010 at the Kennedy Space Center (KSC) launch facility in Cape Canaveral, Florida as a member of the NASA USRP (Undergraduate Student Research Program) program. I worked in the Surface Systems (NE-S) group during the internship. Within NE-S, two ASRC (Arctic Slope Regional Corporation) contract engineers, A.J. Nick and Jason Schuler, had developed a "Quick-Attach" mechanism for the Chariot Rover, the next generation lunar rover. My project was to design, analyze, and possibly fabricate a mounting interface between their "Quick-Attach" and a Hummer vehicle. This interface was needed because it would increase their capabilities to test the Quick Attach and its various attachments, as they do not have access to a Chariot Rover at KSC. I utilized both Pro Engineer, a 3D CAD software package, and a Coordinate Measuring Machine (CMM) known as a FAROarm to collect data and create my design. I relied on hand calculations and the Mechanica analysis tool within Pro Engineer to perform stress analysis on the design. After finishing the design, I began working on creating professional level CAD drawings and issuing them into the KSC design database known as DDMS before the end of the internship.

Grismore, David A.

2010-01-01

353

The 7.5K lbf thrust engine preliminary design for Orbit Transfer Vehicle  

NASA Technical Reports Server (NTRS)

This document summarizes the preliminary design of the Aerojet version of the Orbit Transfer Vehicle main engine. The concept of a 7500 lbf thrust LO2/GH2 engine using the dual expander cycle for optimum efficiency is validated through power balance and thermal calculations. The engine is capable of 10:1 throttling from a nominal 2000 psia to a 200 psia chamber pressure. Reservations are detailed on the feasibility of a tank head start, but the design incorporates low speed turbopumps to mitigate the problem. The mechanically separate high speed turbopumps use hydrostatic bearings to meet engine life requirements, and operate at sub-critical speed for better throttling ability. All components were successfully packaged in the restricted envelope set by the clearances for the extendible/retractable nozzle. Gimbal design uses an innovative primary and engine out gimbal system to meet the +/- 20 deg gimbal requirement. The hydrogen regenerator and LOX/GH2 heat exchanger uses the Aerojet platelet structures approach for a highly compact component design. The extendible/retractable nozzle assembly uses an electric motor driven jack-screw design and a one segment carbon-carbon or silicide coated columbium nozzle with an area ratio, when extended, of 1430:1. A reliability analysis and risk assessment concludes the report.

Hayden, Warren R.; Sabiers, Ralph; Schneider, Judy

1994-01-01

354

Design and implementation of a biomimetic turtle hydrofoil for an autonomous underwater vehicle.  

PubMed

This paper presents the design and implementation of a turtle hydrofoil for an Autonomous Underwater Vehicle (AUV). The final design of the AUV must have navigation performance like a turtle, which has also been the biomimetic inspiration for the design of the hydrofoil and propulsion system. The hydrofoil design is based on a National Advisory Committee for Aeronautics (NACA) 0014 hydrodynamic profile. During the design stage, four different propulsion systems were compared in terms of propulsion path, compactness, sealing and required power. The final implementation is based on a ball-and-socket mechanism because it is very compact and provides three degrees of freedom (DoF) to the hydrofoil with very few restrictions on the propulsion path. The propulsion obtained with the final implementation of the hydrofoil has been empirically evaluated in a water channel comparing different motion strategies. The results obtained have confirmed that the proposed turtle hydrofoil controlled with a mechanism with three DoF generates can be used in the future implementation of the planned AUV. PMID:22247660

Font, Davinia; Tresanchez, Marcel; Siegentahler, Cedric; Pallej, Toms; Teixid, Merc; Pradalier, Cedric; Palacin, Jordi

2011-01-01

355

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)

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.

1979-01-01

356

Abstract--In this work is proposed the design of a system to create and handle Electric Vehicles (EV) charging procedures,  

E-print Network

Abstract--In this work is proposed the design of a system to create and handle Electric Vehicles network limitation and absence of smart meter devices, Electric Vehicles charging should be performed application to assist the EV driver on these processes. This proposed Smart Electric Vehicle Charging System

da Silva, Alberto Rodrigues

357

Development of an aggregation methodology for risk analysis in aerospace conceptual vehicle design  

NASA Astrophysics Data System (ADS)

The growing complexity of technical systems has emphasized a need to gather as much information as possible regarding specific systems of interest in order to make robust, sound decisions about their design and deployment. Acquiring as much data as possible requires the use of empirical statistics, historical information and expert opinion. In much of the aerospace conceptual design environment, the lack of historical information and infeasibility of gathering empirical data relegates the data collection to expert opinion. The conceptual design of a space vehicle requires input from several disciplines (weights and sizing, operations, trajectory, etc.). In this multidisciplinary environment, the design variables are often not easily quantified and have a high degree of uncertainty associated with their values. Decision-makers must rely on expert assessments of the uncertainty associated with the design variables to evaluate the risk level of a conceptual design. Since multiple experts are often queried for their evaluation of uncertainty, a means to combine/aggregate multiple expert assessments must be developed. Providing decision-makers with a solitary assessment that captures the consensus of the multiple experts would greatly enhance the ability to evaluate risk associated with a conceptual design. The objective of this research has been to develop an aggregation methodology that efficiently combines the uncertainty assessments of multiple experts in multiple disciplines involved in aerospace conceptual design. Bayesian probability augmented by uncertainty modeling and expert calibration was employed in the methodology construction. Appropriate questionnaire techniques were used to acquire expert opinion; the responses served as input distributions to the aggregation algorithm. Application of the derived techniques were applied as part of a larger expert assessment elicitation and calibration study. Results of this research demonstrate that aggregation of uncertainty assessments in environments where likelihood functions and empirically assessed expert credibility factors are deficient is possible. Validation of the methodology provides evidence that decision-makers find the aggregated responses useful in formulating decision strategies.

Chytka, Trina Marsh

2003-10-01

358

> 070131-073Vehicle  

E-print Network

. INTRODUCTION The design and deployment of network centric vehicle control frameworks in a systematic manner> 070131-073Vehicle for Network Centric Operations H. Ferreira from Porto University. Swordfish has an advanced control architecture for multi-vehicle operations

Marques, Eduardo R. B.

359

Evaluation of Design Method for Engine Output and Battery Capacity for Lithium Ion-Battery Hybrid Diesel Railway Vehicles  

NASA Astrophysics Data System (ADS)

Diesel engine lithium-ion battery hybrid vehicles are gaining attention because the energy consumption during their operation and exhaust emission can be reduced considerably. However, designing a reasonably accurate method for the engine power and battery energy has not yet been proposed, though the above mentioned type of traction system can help in realizing an environment-friendly railway vehicle. In this paper, a design method for the battery capacity (energy) and engine output is proposed in the case of a control strategy in which the sum of the kinetic energy of the vehicle and the battery energy is maintained constant. The proposed method is verified by the velocity/state of charge of the battery charts obtained in the experimental tests. The proposed design method can be used to develop the environment-friendly railway traction systems for non electrified lines.

Shiraki, Naoki; Kondo, Keiichiro

360

Solar Electric Propulsion Technologies Being Designed for Orbit Transfer Vehicle Applications  

NASA Technical Reports Server (NTRS)

There is increasing interest in employing Solar Electric Propulsion (SEP) for new missions requiring transfer from low Earth orbit to the Earth-Moon Lagrange point, L1. Mission architecture plans place the Gateway Habitat at L1 in the 2011 to 2016 timeframe. The Gateway Habitat is envisioned to be used for Lunar exploration, space telescopes, and planetary mission staging. In these scenarios, an SEP stage, or "tug," is used to transport payloads to L1--such as the habitat module, lunar excursion and return vehicles, and chemical propellant for return crew trips. SEP tugs are attractive because they are able to efficiently transport large (less than 10,000 kg) payloads while minimizing propellant requirements. To meet the needs of these missions, a preliminary conceptual design for a general-purpose SEP tug was developed that incorporates several of the advanced space power and in-space propulsion technologies (such as high-power gridded ion and Hall thrusters, high-performance thin-film photovoltaics, lithium-ion batteries, and advanced high-voltage power processing) being developed at the NASA Glenn Research Center. A spreadsheet-based vehicle system model was developed for component sizing and is currently being used for mission planning. This model incorporates a low-thrust orbit transfer algorithm to make preliminary determinations of transfer times and propellant requirements. Results from this combined tug mass estimation and orbit transfer model will be used in a higher fidelity trajectory model to refine the analysis.

Sarver-Verhey, Timothy R.; Hoffman, David J.; Kerslake, Thomas W.; Oleson, Steven R.; Falck, Robert D.

2002-01-01

361

Design considerations for a lithium-aluminum/iron sulfide electric vehicle battery  

NASA Astrophysics Data System (ADS)

A study has been made of battery-vehicle design interactions using a Toyota Carina converted to electric drive with a Li-Al/FeS battery used as a power and energy source. Energy and power requirements were calculated based on a range of 120 or 200 km with acceleration requirements typical of today's internal-combustion automobiles. Cell modeling analysis was employed to relate the specific energy of the battery to its power capability in terms of the P/E ratio, and this relationship was then used to estimate the battery weight and volume. Based on the results of the study, the specifications and performance of a compact electric automobile have been derived. It is concluded that, when fully developed, the Li-Al/FeS battery can provide a power source of high energy and power density for a personal electric vehicle. The battery is safe, rugged, requires no maintenance, and may offer the possibility of range extension through quick recharge.

Chilenskas, A. A.; Gay, E. C.; Shimotake, H.; Barney, D. L.; Kawahara, K.; Goto, K.

362

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

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

363

Design and performance of an insect-inspired nano air vehicle  

NASA Astrophysics Data System (ADS)

This work reports the structural design, actuation and performance of an insect-inspired nano air vehicle. For this purpose, an original design concept of resonant wings using indirect actuation and concise transmission to allow large and symmetrical bending angles, passive wing torsion and to minimize energy expenditure is presented. A simplified analytical model and a numerical approach for the transmission between the actuator and the wings are then proposed to validate the design. The all-polymer prototypes were obtained using micromachining SU-8 photoresist technology. An electromagnetic actuator was added to control the vibrating amplitudes and create passive wing torsion. The actuator was optimized to make it more effective whilst at the same time minimizing its mass. Prototypes with a global wingspan of 3.5 cm and a mass of 22 mg due to the structure and actuator are presented. Bending amplitudes of the wings up to 60 were measured with these prototypes. The resonant frequency of the wings varied according to the design and mass. It was demonstrated that it is possible to obtain, without an important driving mechanism a very promising kinematics.

Bontemps, A.; Vanneste, T.; Paquet, J.-B.; Dietsch, T.; Grondel, S.; Cattan, E.

2013-01-01

364

Design considerations to improve cognitive ergonomic issues of unmanned vehicle interfaces utilizing video game controllers.  

PubMed

Unmanned (UAVs, UCAVs, and UGVs) systems still have major human factors and ergonomic challenges related to the effective design of their control interface systems, crucial to their efficient operation, maintenance, and safety. Unmanned system interfaces with a human centered approach promote intuitive interfaces that are easier to learn, and reduce human errors and other cognitive ergonomic issues with interface design. Automation has shifted workload from physical to cognitive, thus control interfaces for unmanned systems need to reduce mental workload on the operators and facilitate the interaction between vehicle and operator. Two-handed video game controllers provide wide usability within the overall population, prior exposure for new operators, and a variety of interface complexity levels to match the complexity level of the task and reduce cognitive load. This paper categorizes and provides taxonomy for 121 haptic interfaces from the entertainment industry that can be utilized as control interfaces for unmanned systems. Five categories of controllers were based on the complexity of the buttons, control pads, joysticks, and switches on the controller. This allows the selection of the level of complexity needed for a specific task without creating an entirely new design or utilizing an overly complex design. PMID:22317628

Oppold, P; Rupp, M; Mouloua, M; Hancock, P A; Martin, J

2012-01-01

365

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

NASA Technical Reports Server (NTRS)

The development and design of a cryogenic liquid quantity gauge for zero-g applications is 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 +/- 1% of tank volume. Southwest Research Institute (Tm) and NASA-GRC (Glenn Research Center) have developed several previous breadboard and engineering development gauges and tested them in cryogenic hydrogen and nitrogen to establish the gauge capabilities, to resolve several design issues, and to formulate data processing algorithms. The CMG has been selected by NASA's Future X program for a flight demonstration on the USAF (United States Air Force) / Boeing Solar Thermal Vehicle Space Experiment (SOTVSE). This paper reviews the design trade studies needed to satisfy the SOTVSE limitations on CMG power, volume, and mass, and describes the mechanical design of the CMG.

Dodge, Franklin T.; Green, Steven T.; Petullo, Steven P.; VanDresar, Neil T.; Taylor, William J. (Technical Monitor)

2002-01-01

366

Design and characterization of Hover Nano Aerial Vehicle (HNAV) propulsion system  

E-print Network

On October 4th 2005, DARPA released a request for proposals for a Nano-Air Vehicle (NAV) program. The program sought to develop an advanced urban reconnaissance vehicle. According the requirement imposed by DARPA, the NAV ...

Sato, Sho, Ph. D. Massachusetts Institute of Technology

2008-01-01

367

Design of an Autonomous Underwater Vehicle to Calibrate the Europa Clipper Ice-Penetrating Radar  

NASA Astrophysics Data System (ADS)

Jupiter's moon Europa has been prioritized as the target for the Europa Clipper flyby mission. A key science objective for the mission is to remotely characterize the ice shell and any subsurface water, including their heterogeneity, and the nature of surface-ice-ocean exchange. This objective is a critical component of the mission's overarching goal of assessing the habitability of Europa. The instrument targeted for addressing key aspects of this goal is an ice-penetrating radar (IPR). As a primary goal of our work, we will tightly couple airborne IPR studies of the Ross Ice Shelf by the Europa Clipper radar team with ground-truth data to be obtained from sub-glacial sonar and bio-geochemical mapping of the corresponding ice-water and water-rock interfaces using an advanced autonomous underwater vehicle (AUV). The ARTEMIS vehicle - a heavily morphed long-range, low drag variant of the highly successful 4-degree-of-freedom hovering sub-ice ENDURANCE bot -- will be deployed from a sea-ice drill hole adjacent the McMurdo Ice Shelf (MIS) and will perform three classes of missions. The first includes original exploration and high definition mapping of both the ice-water interface and the benthic interface on a length scale (approximately 10 kilometers under-ice penetration radius) that will definitively tie it to the synchronous airborne IPR over-flights. These exploration and mapping missions will be conducted at up to 10 different locations along the MIS in order to capture varying ice thickness and seawater intrusion into the ice shelf. Following initial mapping characterization, the vehicle will conduct astrobiology-relevant proximity operations using bio-assay sensors (custom-designed UV fluorescence and machine-vision-processed optical imagery) followed by point-targeted studies at regions of interest. Sample returns from the ice-water interface will be triggered autonomously using real-time-processed instrument data and onboard decision-to-collect algorithms. ARTEMIS will be capable of conducting precision hovering proximity science in an unexplored environment, followed by high speed (1.5 m/s) return to the melt hole. The navigation system will significantly advance upon the successes of the prior DEPTHX and ENDURANCE systems and several novel pose-drift correction technologies will be developed and tested under ice during the project. The method of down-hole deployment and auto-docking return will be extended to a vertically-deployed, horizontally-recovered concept that is depth independent and highly relevant to an ice-water deployment on an icy moon. The presentation will discuss the mission down-select architecture for the ARTEMIS vehicle and its implications for the design of a Europa 'fast mover' carrier AUV, the onboard instrument suite, and the Antarctic mission CONOPS. The vehicle and crew will deploy to Antarctica in the 2015/2016 season.

Stone, W.; Siegel, V.; Kimball, P.; Richmond, K.; Flesher, C.; Hogan, B.; Lelievre, S.

2013-12-01

368

Design of a radiation surveillance unit for an unmanned aerial vehicle.  

PubMed

This paper describes a prototype of a compact environmental radiation surveillance instrument designed for a Ranger unmanned aerial vehicle. The instrument, which can be used for tracking a radioactive plume, mapping fallout and searching for point sources, consists of three different detector types (GM, NaI(Tl) and CZT) and an air sampling unit. In addition to the standard electronics for data acquisition, the system contains an onboard computer, a GPS receiver and environmental sensors, all enclosed in a single housing manufactured of fiberglass-reinforced composite material. The data collected during the flight is transmitted in real-time to the ground station via a TETRA radio network. The radiation surveillance unit is an independent module and as such can be used in, for example, airplanes, helicopters and cars. PMID:15748656

Kurvinen, K; Smolander, P; Pllnen, R; Kuukankorpi, S; Kettunen, M; Lyytinen, J

2005-01-01

369

Aerodynamic heating and surface temperatures on vehicles for computer-aided design studies  

NASA Technical Reports Server (NTRS)

A computer subprogram has been developed to calculate aerodynamic and radiative heating rates and to determine surface temperatures by integrating the heating rates along the trajectory of a vehicle. Convective heating rates are calculated by applying the axisymmetric analogue to inviscid surface streamlines and using relatively simple techniques to calculate laminar, transitional, or turbulent heating rates. Options are provided for the selection of gas model, transition criterion, turbulent heating method, Reynolds Analogy factor, and entropy-layer swallowing effects. Heating rates are compared to experimental data, and the time history of surface temperatures are given for a high-speed trajectory. The computer subprogram is developed for preliminary design and mission analysis where parametric studies are needed at all speeds.

Dejarnette, F. R.; Kania, L. A.; Chitty, A.

1983-01-01

370

Analysis, Design and Optimization of Non-Cylindrical Fuselage for Blended-Wing-Body (BWB) Vehicle  

NASA Technical Reports Server (NTRS)

Initial results of an investigation towards finding an efficient non-cylindrical fuselage configuration for a conceptual blended-wing-body flight vehicle were presented. A simplified 2-D beam column analysis and optimization was performed first. Then a set of detailed finite element models of deep sandwich panel and ribbed shell construction concepts were analyzed and optimized. Generally these concepts with flat surfaces were found to be structurally inefficient to withstand internal pressure and resultant compressive loads simultaneously. Alternatively, a set of multi-bubble fuselage configuration concepts were developed for balancing internal cabin pressure load efficiently, through membrane stress in inner-stiffened shell and inter-cabin walls. An outer-ribbed shell was designed to prevent buckling due to external resultant compressive loads. Initial results from finite element analysis appear to be promising. These concepts should be developed further to exploit their inherent structurally efficiency.

Mukhopadhyay, V.; Sobieszczanski-Sobieski, J.; Kosaka, I.; Quinn, G.; Charpentier, C.

2002-01-01

371

Autonomous Underwater Vehicle Survey Design for Monitoring Carbon Capture and Storage Sites  

NASA Astrophysics Data System (ADS)

Long-term monitoring of sub-seabed Carbon Capture and Storage (CCS) sites will require systems that are flexible, independent, and have long-endurance. In this presentation we will discuss the utility of autonomous underwater vehicles equipped with different sensor packages in monitoring storage sites. We will present data collected using Autosub AUV, as part of the ECO2 project, from the Sleipner area of the North Sea. The Autosub AUV was equipped with sidescan sonar, an EM2000 multibeam systems, a Chirp sub-bottom profiler, and a variety of chemical sensors. Our presentation will focus on survey design, and the simultaneous use of multiple sensor packages in environmental monitoring on the continental shelf.

Bull, J. M.; Cevatoglu, M.; Connelly, D.; Wright, I. C.; McPhail, S.; Shitashima, K.

2013-12-01

372

Reconfigurable Flight Control Designs With Application to the X-33 Vehicle  

NASA Technical Reports Server (NTRS)

Two methods for control system reconfiguration have been investigated. The first method is a robust servomechanism control approach (optimal tracking problem) that is a generalization of the classical proportional-plus-integral control to multiple input-multiple output systems. The second method is a control-allocation approach based on a quadratic programming formulation. A globally convergent fixed-point iteration algorithm has been developed to make onboard implementation of this method feasible. These methods have been applied to reconfigurable entry flight control design for the X-33 vehicle. Examples presented demonstrate simultaneous tracking of angle-of-attack and roll angle commands during failures of the right body flap actuator. Although simulations demonstrate success of the first method in most cases, the control-allocation method appears to provide uniformly better performance in all cases.

Burken, John J.; Lu, Ping; Wu, Zhenglu

1999-01-01

373

Design of a Multi-Sensor Cooperation Travel Environment Perception System for Autonomous Vehicle  

PubMed Central

This paper describes the environment perception system designed for intelligent vehicle SmartV-II, which won the 2010 Future Challenge. This system utilizes the cooperation of multiple lasers and cameras to realize several necessary functions of autonomous navigation: road curb detection, lane detection and traffic sign recognition. Multiple single scan lasers are integrated to detect the road curb based on Z-variance method. Vision based lane detection is realized by two scans method combining with image model. Haar-like feature based method is applied for traffic sign detection and SURF matching method is used for sign classification. The results of experiments validate the effectiveness of the proposed algorithms and the whole system.

Chen, Long; Li, Qingquan; Li, Ming; Zhang, Liang; Mao, Qingzhou

2012-01-01

374

How to conduct a car? A design example for maneuver based driver-vehicle interaction  

Microsoft Academic Search

Conduct-by-Wire is a vehicle guidance paradigm, which investigates the possibility of controlling an automobile by maneuver commands. The focus of this paper is to show one possible interaction strategy for maneuver-based vehicle guidance between driver and vehicle by means of discrete maneuvers. Therefore, the paper starts with a short introduction to the advantages of maneuver-based vehicle guidance and proceeds to

M. Kauer; M. Schreiber; R. Bruder

2010-01-01

375

Design, demonstrations and sustainability impact assessments for plug-in hybrid electric vehicles  

Microsoft Academic Search

Plug-in hybrid electric vehicles (PHEVs) are hybrid electric vehicles that can draw and store energy from an electric grid to supply propulsive energy for the vehicle. This simple functional change to the conventional hybrid electric vehicle allows a plug-in hybrid to displace petroleum energy with multi-source electrical energy. This has important and generally beneficial impacts on transportation energy sector petroleum

Thomas H. Bradley; Andrew A. Frank

2009-01-01

376

Design of a docking station for solar charged electric and fuel cell vehicles  

Microsoft Academic Search

An effect of constant increase in the price of hydrocarbon-based fuels and the resulting pollution of environment have motivated researchers and the automobile industry to take a serious look at electric vehicles (EV). Hybrid technologies have also found their place in the automobile industry. Hybrid Electric and Plug-in Hybrid Electric Vehicles are being developed and improved constantly. An electric vehicle

Diego M. Robalino; Ganapathy Kumar; L. O. Uzoechi; U. C. Chukwu; S. M. Mahajan

2009-01-01

377

Reliability-Based Design Optimization for Durability of Ground Vehicle Suspension System Components  

E-print Network

in attaining vehicle performance of critical structural components in complex systems (e.g., a vehicle structures (e.g., multilay- ered structures made from high specific-strength metals and ballistic fiber their blast/ballistic survivability), it is critical to ensure that vehicle life time does not become governed

Grujicic, Mica

378

Assessment, design and control strategy development of a fuel cell hybrid electric vehicle for CSU's EcoCAR  

NASA Astrophysics Data System (ADS)

Advanced automotive technology assessment and powertrain design are increasingly performed through modeling, simulation, and optimization. But technology assessments usually target many competing criteria making any individual optimization challenging and arbitrary. Further, independent design simulations and optimizations take considerable time to execute, and design constraints and objectives change throughout the design process. Changes in design considerations usually require re-processing of simulations and more time. In this thesis, these challenges are confronted through CSU's participation in the EcoCAR2 hybrid vehicle design competition. The complexity of the competition's design objectives leveraged development of a decision support system tool to aid in multi-criteria decision making across technologies and to perform powertrain optimization. To make the decision support system interactive, and bypass the problem of long simulation times, a new approach was taken. The result of this research is CSU's architecture selection and component sizing, which optimizes a composite objective function representing the competition score. The selected architecture is an electric vehicle with an onboard range extending hydrogen fuel cell system. The vehicle has a 145kW traction motor, 18.9kWh of lithium ion battery, a 15kW fuel cell system, and 5kg of hydrogen storage capacity. Finally, a control strategy was developed that improves the vehicles performance throughout the driving range under variable driving conditions. In conclusion, the design process used in this research is reviewed and evaluated against other common design methodologies. I conclude, through the highlighted case studies, that the approach is more comprehensive than other popular design methodologies and is likely to lead to a higher quality product. The upfront modeling work and decision support system formulation will pay off in superior and timely knowledge transfer and more informed design decisions. The hypothesis is supported by the three case studies examined in this thesis.

Fox, Matthew D.

379

Vehicle Sketch Pad: a Parametric Geometry Modeler for Conceptual Aircraft Design  

NASA Technical Reports Server (NTRS)

The conceptual aircraft designer is faced with a dilemma, how to strike the best balance between productivity and fidelity? Historically, handbook methods have required only the coarsest of geometric parameterizations in order to perform analysis. Increasingly, there has been a drive to upgrade analysis methods, but these require considerably more precise and detailed geometry. Attempts have been made to use computer-aided design packages to fill this void, but their cost and steep learning curve have made them unwieldy at best. Vehicle Sketch Pad (VSP) has been developed over several years to better fill this void. While no substitute for the full feature set of computer-aided design packages, VSP allows even novices to quickly become proficient in defining three-dimensional, watertight aircraft geometries that are adequate for producing multi-disciplinary meta-models for higher order analysis methods, wind tunnel and display models, as well as a starting point for animation models. This paper will give an overview of the development and future course of VSP.

Hahn, Andrew S.

2010-01-01

380

Design of a reconfigurable liquid hydrogen fuel tank for use in the Genii unmanned aerial vehicle  

SciTech Connect

Long endurance flight, on the order of days, is a leading flight performance characteristic for Unmanned Aerial Vehicles (UAVs). Liquid hydrogen (LH2) is well suited to providing multi-day flight times with a specific energy 2.8 times that of conventional kerosene based fuels. However, no such system of LH2 storage, delivery, and use is currently available for commercial UAVs. In this paper, we develop a light weight LH2 dewar for integration and testing in the proton exchange membrane (PEM) fuel cell powered, student designed and constructed, Genii UAV. The fuel tank design is general for scaling to suit various UAV platforms. A cylindrical vacuum-jacketed design with removable end caps was chosen to incorporate various fuel level gauging, pressurizing, and slosh mitigation systems. Heat and mechanical loadings were modeled to compare with experimental results. Mass performance of the fuel tank is characterized by the fraction of liquid hydrogen to full tank mass, and the insulation performance was characterized by effective thermal conductivity and boil-off rate.

Adam, Patrick; Leachman, Jacob [HYdrogen Properties for Energy Research (HYPER) Laboratory, Washington State University, Pullman, WA 99164-2920 (United States)

2014-01-29

381

A Water Vapor Differential Absorption LIDAR Design for Unpiloted Aerial Vehicles  

NASA Technical Reports Server (NTRS)

This system study proposes the deployment of a water vapor Differential Absorption LIDAR (DIAL) system on an Altair unmanned aerial vehicle (UAV) platform. The Altair offers improved payload weight and volume performance, and longer total flight time as compared to other commercial UAV's. This study has generated a preliminary design for an Altair based water vapor DIAL system. The design includes a proposed DIAL schematic, a review of mechanical challenges such as temperature and humidity stresses on UAV deployed DIAL systems, an assessment of the available capacity for additional instrumentation (based on the proposed design), and an overview of possible weight and volume improvements associated with the use of customized electronic and computer hardware, and through the integration of advanced fiber-optic and laser products. The results of the study show that less than 17% of the available weight, less than 19% of the volume capacity, and approximately 11% of the electrical capacity is utilized by the proposed water vapor DIAL system on the Altair UAV.

DeYoung, Russell J.; Mead, Patricia F.

2004-01-01

382

Aerodynamic Design Exploration for Reusable Launch Vehicle Using Genetic Algorithm with Navier Stokes Solver  

NASA Astrophysics Data System (ADS)

In this study, aerodynamic design exploration for reusable launch vehicle (RLV) is conducted using genetic algorithm with Navier-Stokes solver to understand the aerodynamic characteristics for various body configurations and find design information such as tradeoff information among objectives. The multi-objective aerodynamic design optimization for minimizing zero-lift drag at supersonic condition, maximizing maximum lift-to-drag ratio (L/D) at subsonic condition, maximizing maximum L/D at supersonic condition, and maximizing volume of shape is conducted for bi-conical shape RLV based on computational fluid dynamics (CFD). The total number of evaluation in multi-objective optimization is 400, and it is necessary for evaluating one body configuration to conduct 8 CFD runs. In total, 3200 CFD runs are conducted. The analysis of Pareto-optimal solutions shows that there are various trade-off relations among objectives clearly, and the analysis of flow fields shows that the shape for the minimum drag configuration is almost the same as that of the shape for the maximum L/D configuration at supersonic condition. The shape for the maximum L/D at subsonic condition obtains additional lift at the kink compared with the minimum drag configuration. It leads to enhancement of L/D.

Tatsukawa, Tomoaki; Nonomura, Taku; Oyama, Akira; Fujii, Kozo

383

Design of a reconfigurable liquid hydrogen fuel tank for use in the Genii unmanned aerial vehicle  

NASA Astrophysics Data System (ADS)

Long endurance flight, on the order of days, is a leading flight performance characteristic for Unmanned Aerial Vehicles (UAVs). Liquid hydrogen (LH2) is well suited to providing multi-day flight times with a specific energy 2.8 times that of conventional kerosene based fuels. However, no such system of LH2 storage, delivery, and use is currently available for commercial UAVs. In this paper, we develop a light weight LH2 dewar for integration and testing in the proton exchange membrane (PEM) fuel cell powered, student designed and constructed, Genii UAV. The fuel tank design is general for scaling to suit various UAV platforms. A cylindrical vacuum-jacketed design with removable end caps was chosen to incorporate various fuel level gauging, pressurizing, and slosh mitigation systems. Heat and mechanical loadings were modeled to compare with experimental results. Mass performance of the fuel tank is characterized by the fraction of liquid hydrogen to full tank mass, and the insulation performance was characterized by effective thermal conductivity and boil-off rate.

Adam, Patrick; Leachman, Jacob

2014-01-01

384

Ergonomic risk assessment with DesignCheck to evaluate assembly work in different phases of the vehicle development process.  

PubMed

Occupational hazards exist, if the design of the work situation is not in accordance with ergonomic design principles. At assembly lines ergonomics is applied to the design of work equipment and tasks and to work organisation. The ignoring of ergonomic principles in planning and design of assembly work leads to unfavourable working posture, action force and material handling. Disorders of the musculoskeletal system are of a common occurrence throughout Europe. Musculoskeletal disorders are a challenge against the background of disabled workers. The changes in a worker's capability have to be regarded in the conception of redesigned and new assembly lines. In this way ergonomics becomes progressively more important in planning and design of vehicles: The objective of ergonomic design in different stages of the vehicles development process is to achieve an optimal adaptation of the assembly work to workers. Hence the ergonomic screening tool "Design Check" (DC) was developed to identify ergonomic deficits in workplace layouts. The screening-tool is based on the current ergonomic state of the art in the design of physical work and relevant EU legal requirements. It was tested within a federal German research project at selected work stations at the assembly lines at Dr.-Ing. h.c. F. Porsche AG / Stuttgart. Meanwhile the application of the screening-tool DC is transferred in other parts of the Porsche AG, Stuttgart. It is also realized as an ergonomic standard method to perform assembly work in different phases of the vehicle development process. PMID:22317393

Winter, Gabriele; Schaub, Karlheinz G; Gromann, Kay; Laun, Gerhard; Landau, Kurt; Bruder, Ralph

2012-01-01

385

Design and exploitation of supervisory control system for commercial electric vehicle charging station based on virtual DPU technology  

Microsoft Academic Search

Based on virtual distributed processing unit (DPU) technology of distributed control system (DCS), a supervisory control system for commercial electric vehicle charging station was designed and exploited. The real time data exchange between charger and virtual DPU of supervisory control system was realized with CAN bus. Virtual DPU configuration function was used to exploit the control logic and monitoring interface.

Xiaoxing Zhu; Houtao Chen; Wulin Liu; Jie Luo

2010-01-01

386

Highly efficient brushless motor design for an air-conditioner of the next generation 42 V vehicle  

Microsoft Academic Search

In the past few years, worldwide awareness of environmental problems has grown dramatically. The idling stop and 42 V battery system has attracted large attention for next generation vehicle. In order to adapt to idling stop, air-conditioning compressors are required to be changed to electric-motor driven from gasoline engine driven. This paper discusses the optimum design of a high speed

Hiroshi Murakami; Hisakazu Kataoka; Yukio Honda; Shigeo Morimoto; Yoji Takeda

2001-01-01

387

Curriculum Materials as a Vehicle for Innovation: a case study of the Nuffield Design and Technology Project  

Microsoft Academic Search

Prior to the advent of the National Curriculum in England and Wales, the production of teaching materials was an established vehicle for curriculum change. The Nuffield Design and Technology Project recently published extensive materials which enlarge upon the National Curriculum. This paper presents an investigation based on case studies of two teachers in separate schools, each using Nuffield publications with

Nick Givens

2000-01-01

388

Passivity Analysis and Design of Passivity-Based Controllers for Trajectory Tracking at High Speed of Autonomous Vehicles  

E-print Network

vehicles. In liter- ature, many control strategies have been developed. Simple PID controllers have beenPassivity Analysis and Design of Passivity-Based Controllers for Trajectory Tracking at High Speed are under inten- sive development, especially this last decade. This paper focuses on the lateral control

Paris-Sud XI, Université de

389

Constellation Program (CxP) Crew Exploration Vehicle (CEV) Parachute Assembly System (CPAS) Independent Design Reliability Assessment. Volume 1  

NASA Technical Reports Server (NTRS)

This report documents the activities, findings, and NASA Engineering and Safety Center (NESC) recommendations of a multidiscipline team to independently assess the Constellation Program (CxP) Crew Exploration Vehicle (CEV) Parachute Assembly System (CPAS). This assessment occurred during a period of 15 noncontiguous months between December 2008 and April 2010, prior to the CPAS Project's Preliminary Design Review (PDR) in August 2010.

Kelly, Michael J.

2010-01-01

390

Mars Lander/Rover vehicle development: An advanced space design project for USRA and NASA/OAST  

NASA Technical Reports Server (NTRS)

The accomplishments of the Utah State University (USU) Mars Lander/Rover (MLR) design class during the Winter Quarter are delineated and explained. Environment and trajectory, ground systems, balloon system, and payload system are described. Results from this effort will provide a valid and useful basis for further studies of Mars exploratory vehicles.

1987-01-01

391

Nuclear Thermal Rocket/Vehicle Design Options for Future NASA Missions to the Moon and Mars  

NASA Technical Reports Server (NTRS)

The nuclear thermal rocket (NTR) provides a unique propulsion capability to planners/designers of future human exploration missions to the Moon and Mars. In addition to its high specific impulse (approximately 850-1000 s) and engine thrust-to-weight ratio (approximately 3-10), the NTR can also be configured as a 'dual mode' system capable of generating electrical power for spacecraft environmental systems, communications, and enhanced stage operations (e.g., refrigeration for long-term liquid hydrogen storage). At present the Nuclear Propulsion Office (NPO) is examining a variety of mission applications for the NTR ranging from an expendable, single-burn, trans-lunar injection (TLI) stage for NASA's First Lunar Outpost (FLO) mission to all propulsive, multiburn, NTR-powered spacecraft supporting a 'split cargo-piloted sprint' Mars mission architecture. Each application results in a particular set of requirements in areas such as the number of engines and their respective thrust levels, restart capability, fuel operating temperature and lifetime, cryofluid storage, and stage size. Two solid core NTR concepts are examined -- one based on NERVA (Nuclear Engine for Rocket Vehicle Application) derivative reactor (NDR) technology, and a second concept which utilizes a ternary carbide 'twisted ribbon' fuel form developed by the Commonwealth of Independent States (CIS). The NDR and CIS concepts have an established technology database involving significant nuclear testing at or near representative operating conditions. Integrated systems and mission studies indicate that clusters of two to four 15 to 25 klbf NDR or CIS engines are sufficient for most of the lunar and Mars mission scenarios currently under consideration. This paper provides descriptions and performance characteristics for the NDR and CIS concepts, summarizes NASA's First Lunar Outpost and Mars mission scenarios, and describes characteristics for representative cargo and piloted vehicles compatible with a reference 240 t-class heavy lift launch vehicle (HLLV) and smaller 120 t HLLV option. Attractive performance characteristics and high-leverage technologies associated with both the engine and stage are identified, and supporting parametric sensitivity data is provided. The potential for commonality of engine and stage components to satisfy a broad range of lunar and Mars missions is also discussed.

Borowski, Stanley K.; Corban, Robert R.; Mcguire, Melissa L.; Beke, Erik G.

1995-01-01

392

Tools for Designing Thermal Management of Batteries in Electric Drive Vehicles (Presentation)  

SciTech Connect

Temperature has a significant impact on life, performance, and safety of lithium-ion battery technology, which is expected to be the energy storage of choice for electric drive vehicles (xEVs). High temperatures degrade Li-ion cells faster while low temperatures reduce power and energy capabilities that could have cost, reliability, range, or drivability implications. Thermal management of battery packs in xEVs is essential to keep the cells in the desired temperature range and also reduce cell-to-cell temperature variations, both of which impact life and performance. The value that the battery thermal management system provides in reducing battery life and improving performance outweighs its additional cost and complexity. Tools that are essential for thermal management of batteries are infrared thermal imaging, isothermal calorimetry, thermal conductivity meter and computer-aided thermal analysis design software. This presentation provides details of these tools that NREL has used and we believe are needed to design right-sized battery thermal management systems.

Pesaran, A.; Keyser, M.; Kim, G. H.; Santhanagopalan, S.; Smith, K.

2013-02-01

393

Design and performance evaluation of a rotary magnetorheological damper for unmanned vehicle suspension systems.  

PubMed

We designed and validated a rotary magnetorheological (MR) damper with a specified damping torque capacity, an unsaturated magnetic flux density (MFD), and a high magnetic field intensity (MFI) for unmanned vehicle suspension systems. In this study, for the rotary type MR damper to have these satisfactory performances, the roles of the sealing location and the cover case curvature of the MR damper were investigated by using the detailed 3D finite element model to reflect asymmetrical shapes and sealing components. The current study also optimized the damper cover case curvature based on the MFD, the MFI, and the weight of the MR damper components. The damping torques, which were computed using the characteristic equation of the MR fluid and the MFI of the MR damper, were 239.2, 436.95, and 576.78 Nm at currents of 0.5, 1, and 1.5 A, respectively, at a disk rotating speed of 10 RPM. These predicted damping torques satisfied the specified damping torque of 475 Nm at 1.5 A and showed errors of less than 5% when compared to experimental measurements from the MR damper manufactured by the proposed design. The current study could play an important role in improving the performance of rotary type MR dampers. PMID:23533366

Lee, Jae-Hoon; Han, Changwan; Ahn, Dongsu; Lee, Jin Kyoo; Park, Sang-Hu; Park, Seonghun

2013-01-01

394

Design, building, and testing of the post landing systems for the assured crew return vehicle  

NASA Technical Reports Server (NTRS)

The design, building, and testing of the post landing support systems for a water landing Assured Crew Return Vehicle (ACRV) are presented. One ACRV will be permanently docked to Space Station Freedom, fulfilling NASA's commitment to Assured Crew Return Capability in the event of an accident or illness. The configuration of the ACRV is based on an Apollo Command Module (ACM) derivative. The 1990 to 91 effort concentrated on the design, building, and testing of a 1/5 scale model of the egress and stabilization systems. The objective was to determine the feasibility of: (1) stabilizing the ACM out of the range of motions which cause sea sickness; and (2) the safe and rapid removal of a sick or injured crewmember from the ACRV. The ACRV model construction is presented along with a discussion of the water test facility. The rapid egress system is also presented along with a discussion of the ACRV stabilization control systems. Results are given and discussed in detail.

Anderson, Loren A.

1991-01-01

395

A Modularized Design for Multi-drivers Off-road Vehicle Driving-line and its Performance Assessment  

Microsoft Academic Search

Modularized design approach can facilitate the modeling of complex systems and support behavior analysis and simulation in an iterative and thus complex engineering process, by using encapsulated submodels of components and of their interfaces. Therefore it can improve the design efficiency and simplify the solving complicated problem. Multi-drivers off-road vehicle is comparatively complicated. Driving-line is an important core part to

Yi Jianjun; Sun Yingce; Hu Diqing; Li Chenggang

2007-01-01

396

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)

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.

Piccolo, R.

1979-01-01

397

Modeling, Simulation Design and Control of Hybrid-Electric Vehicle Drives  

SciTech Connect

Ohio State University (OSU) is uniquely poised to establish such a center, with interdisciplinary emphasis on modeling, simulation, design and control of hybrid-electric drives for a number of reasons, some of which are: (1) The OSU Center for Automotive Research (CAR) already provides an infrastructure for interdisciplinary automotive research and graduate education; the facilities available at OSU-CAR in the area of vehicle and powertrain research are among the best in the country. CAR facilities include 31,000 sq. feet of space, multiple chassis and engine dynamometers, an anechoic chamber, and a high bay area. (2) OSU has in excess of 10 graduate level courses related to automotive systems. A graduate level sequence has already been initiated with GM. In addition, an Automotive Systems Engineering (ASE) program cosponsored by the mechanical and electrical engineering programs, had been formulated earlier at OSU, independent of the GATE program proposal. The main objective of the ASE is to provide multidisciplinary graduate education and training in the field of automotive systems to Masters level students. This graduate program can be easily adapted to fulfill the spirit of the GATE Center of Excellence. (3) A program in Mechatronic Systems Engineering has been in place at OSU since 1994; this program has a strong emphasis on automotive system integration issues, and has emphasized hybrid-electric vehicles as one of its application areas. (4) OSU researchers affiliated with CAR have been directly involved in the development and study of: HEV modeling and simulation; electric drives; transmission design and control; combustion engines; and energy storage systems. These activities have been conducted in collaboration with government and automotive industry sponsors; further, the same researchers have been actively involved in continuing education programs in these areas with the automotive industry. The proposed effort will include: (1) The development of a laboratory facility that will include: electric drive and IC engine test benches; a test vehicle designed for rapid installation of prototype drives; benches for the measurement and study of HEV energy storage components (batteries, ultra-capacitors, flywheels); hardware-in-the-loop control system development tools. (2) The creation of new courses and upgrades of existing courses on subjects related to: HEV modeling and simulation; supervisory control of HEV drivetrains; engine, transmission, and electric drive modeling and control. Specifically, two new courses (one entitled HEV Component Analysis: and the other entitled HEV System Integration and Control) will be developed. Two new labs, that will be taught with the courses (one entitled HEV Components Lab and one entitled HEV Systems and Control lab) will also be developed. (3) The consolidation of already existing ties among faculty in electrical and mechanical engineering departments. (4) The participation of industrial partners through: joint laboratory development; internship programs; continuing education programs; research project funding. The proposed effort will succeed because of the already exceptional level of involvement in HEV research and in graduate education in automotive engineering at OSU, and because the PIs have a proven record of interdisciplinary collaboration as evidenced by joint proposals, joint papers, and co-advising of graduate students. OSU has been expanding its emphasis in Automotive Systems for quite some time. This has led to numerous successes such as the establishment of the Center of Automotive Research, a graduate level course sequence with GM, and numerous grants and contracts on automotive research. The GATE Center of Excellence is a natural extension of what educators at OSU already do well.

Giorgio Rizzoni

2005-09-30

398

Design and implementation of the smart meter in vehicle-to-grid  

Microsoft Academic Search

With the development of electric vehicles and smart grid, vehicle-to-grid (V2G) will become an inevitable. This paper presented a smart meter applied to vehicle-to-grid. The smart meter is introduced according to the function and characteristic of energy measurement chip ADE7758 and the microprocessor chip S3C2440 is also used in the circuit system. According to the difference of phase angle between

Libiao Qiao; Xiaojun Liu; Baochen Jiang

2011-01-01

399

Probabilistic Design Analysis (PDA) Approach to Determine the Probability of Cross-System Failures for a Space Launch Vehicle  

NASA Technical Reports Server (NTRS)

Quantifying the probability of significant launch vehicle failure scenarios for a given design, while still in the design process, is critical to mission success and to the safety of the astronauts. Probabilistic risk assessment (PRA) is chosen from many system safety and reliability tools to verify the loss of mission (LOM) and loss of crew (LOC) requirements set by the NASA Program Office. To support the integrated vehicle PRA, probabilistic design analysis (PDA) models are developed by using vehicle design and operation data to better quantify failure probabilities and to better understand the characteristics of a failure and its outcome. This PDA approach uses a physics-based model to describe the system behavior and response for a given failure scenario. Each driving parameter in the model is treated as a random variable with a distribution function. Monte Carlo simulation is used to perform probabilistic calculations to statistically obtain the failure probability. Sensitivity analyses are performed to show how input parameters affect the predicted failure probability, providing insight for potential design improvements to mitigate the risk. The paper discusses the application of the PDA approach in determining the probability of failure for two scenarios from the NASA Ares I project

Shih, Ann T.; Lo, Yunnhon; Ward, Natalie C.

2010-01-01

400

Design and development of the redundant launcher stabilization system for the Atlas 2 launch vehicle  

NASA Technical Reports Server (NTRS)

The Launcher Stabilization System (LSS) is a pneumatic/hydraulic ground system used to support an Atlas launch vehicle prior to launch. The redesign and development activity undertaken to achieve an LSS with increased load capacity and a redundant hydraulic system for the Atlas 2 launch vehicle are described.

Nakamura, M.

1991-01-01

401

Design of genetic-fuzzy control strategy for parallel hybrid electric vehicles  

Microsoft Academic Search

Hybrid Electric Vehicles (HEVs) generate the power required to drive the vehicle via a combination of internal combustion engines and electric generators. To make HEVs as efficient as possible, proper management of the different energy elements is essential. This task is performed using the HEV control strategy. The HEV control strategy is the algorithm according to which energy is produced,

Amir Poursamad; Morteza Montazeri

2008-01-01

402

Analysis and design of a speed and position system for maglev vehicles.  

PubMed

This paper mainly researches one method of speed and location detection for maglev vehicles. As the maglev train doesn't have any physical contact with the rails, it has to use non-contact measuring methods. The technology based on the inductive loop-cable could fulfill the requirement by using an on-board antenna which could detect the alternating magnetic field produced by the loop-cable on rails. This paper introduces the structure of a speed and position system, and analyses the electromagnetic field produced by the loop-cable. The equivalent model of the loop-cable is given and the most suitable component of the magnetic flux density is selected. Then the paper also compares the alternating current (AC) resistance and the quality factor between two kinds of coils which the antenna is composed of. The effect of the rails to the signal receiving is also researched and then the structure of the coils is improved. Finally, considering the common-mode interference, 8-word coils are designed and analyzed. PMID:23012504

Dai, Chunhui; Dou, Fengshan; Song, Xianglei; Long, Zhiqiang

2012-01-01

403

Analysis and Design of a Speed and Position System for Maglev Vehicles  

PubMed Central

This paper mainly researches one method of speed and location detection for maglev vehicles. As the maglev train doesn't have any physical contact with the rails, it has to use non-contact measuring methods. The technology based on the inductive loop-cable could fulfill the requirement by using an on-board antenna which could detect the alternating magnetic field produced by the loop-cable on rails. This paper introduces the structure of a speed and position system, and analyses the electromagnetic field produced by the loop-cable. The equivalent model of the loop-cable is given and the most suitable component of the magnetic flux density is selected. Then the paper also compares the alternating current (AC) resistance and the quality factor between two kinds of coils which the antenna is composed of. The effect of the rails to the signal receiving is also researched and then the structure of the coils is improved. Finally, considering the common-mode interference, 8-word coils are designed and analyzed. PMID:23012504

Dai, Chunhui; Dou, Fengshan; Song, Xianglei; Long, Zhiqiang

2012-01-01

404

Design of Autonomous Navigation Controllers for Unmanned Aerial Vehicles Using Multi-objective Genetic Programming  

E-print Network

Unmanned aerial vehicles (UAVs) have become increasingly popular for many applications, including search and rescue, surveillance, and electronic warfare, but almost all UAVs are con-trolled remotely by humans. Methods of control must be developed before UAVs can become truly autonomous. While the field of evolutionary robotics (ER) has made strides in using evo-lutionary computation (EC) to develop controllers for wheeled mobile robots, little attention has been paid to applying EC to UAV control. EC is an attractive method for developing UAV controllers because it allows the human designer to specify the set of high level goals that are to be solved by artificial evolution. In this research, autonomous navigation controllers were developed using multi-objective genetic programming (GP) for fixed wing UAV applications. Four behavioral fitness functions were derived from flight simulations. Multi-objective GP used these fitness functions to evolve controllers that were able to locate an electromagnetic energy source, to navigate the UAV to that source efficiently using on-board sensor measure-ments, and to circle around the emitter. Controllers were evolved in simulation. To narrow the gap between simulated and real controllers, the simulation environment employed noisy radar signals and a sensor model with realistic inaccuracies. All computations were performed on a

Gregory John Barlow

2004-01-01

405

Aerodynamics of Small Vehicles  

Microsoft Academic Search

In this review we describe the aerodynamic problems that must be addressed in order to design a successful small aerial vehicle. The effects of Reynolds number and aspect ratio (AR) on the design and performance of fixed-wing vehicles are described. The boundary-layer behavior on airfoils is especially important in the design of vehicles in this flight regime. The results of

Thomas J. Mueller

2003-01-01

406

Aerodynamic Design of Heavy Vehicles Reporting Period January 15, 2004 through April 15, 2004  

SciTech Connect

Listed are summaries of the activities and accomplishments during this second-quarter reporting period for each of the consortium participants. The following are some highlights for this reporting period: (1) Experiments and computations guide conceptual designs for reduction of drag due to tractor-trailer gap flow (splitter plate), trailer underbody (wedges), and base drag (base-flap add-ons). (2) Steady and unsteady RANS simulations for the GTS geometry are being finalized for development of clear modeling guidelines with RANS. (3) Full geometry and tunnel simulations on the GCM geometry are underway. (4) CRADA with PACCAR is supporting computational parametric study to determine predictive need to include wind tunnel geometry as limits of computational domain. (5) Road and track test options are being investigated. All is ready for field testing of base-flaps at Crows Landing in California in collaboration with Partners in Advanced Transportation Highways (PATH). In addition, MAKA of Canada is providing the device and Wabash is providing a new trailer. (6) Apparatus to investigate tire splash and spray has been designed and is under construction. Michelin has offered tires with customized threads for this study. (7) Vortex methods have improved techniques for the treatment of vorticity near surfaces and spinning geometries like rotating tires. (8) Wind tunnel experiments on model rail cars demonstrate that empty coal cars exhibit substantial aerodynamic drag compared to full coal cars, indicating that significant fuel savings could be obtained by reducing the drag of empty coal cars. (9) Papers are being prepared for an exclusive conference session on the Heavy Vehicle DOE Aerodynamic Drag Project at the 34th AIAA Fluid Dynamics Conference in Portland, Oregon, June 28-July 1, 2004.

Leonard, A; Chatelain, P; Heineck, J; Browand, F; Mehta, R; Ortega, J; Salari, K; Storms, B; Brown, J; DeChant, L; Rubel, M; Ross, J; Hammache, M; Pointer, D; Roy, C; Hassan, B; Arcas, D; Hsu, T; Payne, J; Walker, S; Castellucci, P; McCallen, R

2004-04-13

407

Friction Stir Weld Application and Tooling Design for the Multi-purpose Crew Vehicle Stage Adapter  

NASA Technical Reports Server (NTRS)

The Multi-Purpose Crew Vehicle (MPCV), commonly known as the Orion capsule, is planned to be the United States' next manned spacecraft for missions beyond low earth orbit. Following the cancellation of the Constellation program and creation of SLS (Space Launch System), the need arose for the MPCV to utilize the Delta IV Heavy rocket for a test launch scheduled for 2014 instead of the previously planned Ares I rocket. As a result, an adapter (MSA) must be used in conjunction with the MPCV to account for the variation in diameter of the launch vehicles; 5.5 meters down to 5.0 meters. Prior to ight article fabrication, a path nder (test article) will be fabricated to ne tune the associated manufacturing processes. The adapter will be comprised of an aluminum frustum (partial cone) that employs isogrid technology and circumferential rings on each end. The frustum will be fabricated by friction stir welding (FSW) three individual panels together on a Vertical Weld Tool (VWT) at NASA Marshall Space Flight Center. Subsequently, each circumferential ring will be friction stir welded to the frustum using a Robotic Weld Tool (RWT). The irregular geometry and large mass of the MSA require that extensive tooling preparation be put into support structures for the friction stir weld. The tooling on the VWT will be comprised of a set of conveyors mounted on pre-existing stanchions so that the MSA will have the ability to be rotated after each of the three friction stir welds. The tooling requirements to friction stir weld the rings with the RWT are somewhat more demanding. To support the mass of the MSA and resist the load of the weld tool, a system of mandrels will be mounted to stanchions and assembled in a circle. The goal of the paper will be to explain the design, fabrication, and assembly of the tooling, to explain the use of friction stir welding on the MSA path nder, and also to discuss the lessons learned and modi cations made in preparation for ight article fabrication in support of the 2014 launch of the Orion MPCV.

Alcorn, John

2013-01-01

408

Design and implementation of cooperative autonomous underwater vehicles for Antarctic exploration  

NASA Astrophysics Data System (ADS)

The present work describes the development of two collaborative Autonomous Underwater Vehicles (AUV) for Antarctic exploration to use them in the Ecuadorian Expeditions to the Scientific Base Pedro Vicente Maldonado in Antarctica. One vehicle is an AUV, called TAUV, with classical torpedo architecture, can work as a platform to transport scientific payload in a determined path in open waters. The TAUV length is 2m and diameter of 0.16m and has got three degree of freedom: pitch, yaw and surge. The vehicle achieves stable control with a set of three pairs of control planes. The other vehicle is an AUV, called HAUV, with Hybrid architecture that combines the best characteristics of the ROV and AUV, high stability in the water column, high maneuverability at low velocity without control planes and efficient hydrodynamics. The HAUV length is less than 1.50 m. The propulsion module is formed by four thrusters, three axial and one oriented vertically, this configuration gives to the HAUV three degrees of freedom: heave, surge and yaw. This vehicle can works as a ROV or an AUV. The hybrid configuration features the vehicle to explore dangerous areas near to the glacier wall. Three collaborative behaviors are discussed: formation flying, point inspection near to the glacier wall, replacement of a missing vehicle. Results of some systems of the TAUV and HAUV from laboratory, sea trials in tropical waters and Antarctic environment are show.

Cadena, A.

2011-06-01

409

Design tradeoff studies and sensitivity analysis, appendices B1 - B4. [hybrid electric vehicles  

NASA Technical Reports Server (NTRS)

Documentation is presented for a program which separately computes fuel and energy consumption for the two modes of operation of a hybrid electric vehicle. The distribution of daily travel is specified as input data as well as the weights which the component driving cycles are given in each of the composite cycles. The possibility of weight reduction through the substitution of various materials is considered as well as the market potential for hybrid vehicles. Data relating to battery compartment weight distribution and vehicle handling analysis is tabulated.

1979-01-01

410

Design and analysis of new fault-tolerant permanent magnet motors for four-wheel-driving electric vehicles  

NASA Astrophysics Data System (ADS)

In this paper, a novel in-wheel permanent-magnet (PM) motor for four-wheel-driving electrical vehicles is proposed. It adopts an outer-rotor topology, which can help generate a large drive torque, in order to achieve prominent dynamic performance of the vehicle. Moreover, by adopting single-layer concentrated-windings, fault-tolerant teeth, and the optimal combination of slot and pole numbers, the proposed motor inherently offers negligible electromagnetic coupling between different phase windings, hence, it possesses a fault-tolerant characteristic. Meanwhile, the phase back electromotive force waveforms can be designed to be sinusoidal by employing PMs with a trapezoidal shape, eccentric armature teeth, and unequal tooth widths. The electromagnetic performance is comprehensively investigated and the optimal design is conducted by using the finite-element method.

Liu, Guohai; Gong, Wensheng; Chen, Qian; Jian, Linni; Shen, Yue; Zhao, Wenxiang

2012-04-01

411

Mitigating vestibular disturbances during space flight using virtual reality training and reentry vehicle design guidelines  

NASA Astrophysics Data System (ADS)

Seventy to eighty percent of astronauts reportedly exhibit undesirable vestibular disturbances during the first few days of weightlessness, including space motion sickness (SMS) and spatial disorientation (SD). SMS presents a potentially dangerous situation, both because critical piloted tasks such as docking maneuvers and emergency reentry may be compromised, and because of the potential for asphyxiation should an astronaut vomit while wearing a space suit. SD can be provocative for SMS as well as become dangerous during an emergency in which it is critical for an astronaut to move quickly through the vehicle. In the U.S. space program, medication is currently used both for prevention and treatment of SMS. However, this approach has had only moderate success, and the side effects of drowsiness and lack of concentration are undesirable. Research suggests that preflight training in virtual reality devices can simulate certain aspects of microgravity and may prove to be an effective countermeasure for SMS and SD. It was hypothesized that exposing subjects preflight to variable virtual orientations, similar to those encountered during space flight, will reduce the incidence and/or severity of SMS and SD. Results from a study conducted at the NASA Johnson Space Center as part of this research demonstrated that this type of training is effective for reducing motion sickness and improving task performance in potentially disorienting visual surroundings, thus suggesting the possibility that such training may prove an effective countermeasure for SMS, SD and related performance decrements that occur in space flight. In addition to the effects associated with weightlessness, almost all astronauts experience vestibular disturbances associated with gravity-transitions incurred during the return to Earth, which could be exacerbated if traveling in a spacecraft that is designed differently than a conventional aircraft. Therefore, for piloted descent and landing operations, reducing vestibular disturbances must be considered in the early phases of spacecraft design. An integrated approach combining vestibular disturbances, mission constraints, and other human concerns is proposed in a spacecraft design solution that concurrently addresses all of the above constraints.

Stroud, Kenneth Joshua

412

An efficient fluid-structure interaction method for conceptual design of flexible micro air vehicle wings: Development, comparison, and application  

NASA Astrophysics Data System (ADS)

This thesis summarizes the development, comparison, and applications of an efficient fluid-structure interaction method capable of simulating the effects that wing flexibility has on micro air vehicle (MAV) performance. Micro air vehicles wing designs often incorporate flexible wing structures that mimic the skeleton / membrane designs found in natural flyers such as bats and insects. However, accurate performance prediction for these wings requires the coupling of the simulation of the fluid physics around the wing and the simulation of the structural deformation. These fluid-structure interaction (FSI) simulations are often accomplished using high fidelity, computationally expensive techniques such as computational fluid dynamics (CFD) for the fluid physics and nonlinear finite element analysis (FEA) for the structural simulation. The main drawback of these methods, especially for use simulating vehicles that are able to be manufactured relatively quickly, is that the computational cost required to perform relevant trade studies on the design is prohibitively large and time-consuming. The main goal of this research is the development of a coupled fluid-structure interaction method computationally efficient and accurate enough to be used for conceptual design of micro air vehicles. An advanced potential flow model is used to calculate aerodynamic performance and loading, while a simplified finite element structural model using frame and shell elements calculates the wing deflection due to aerodynamic loading. The contents of this thesis include a literature survey of current approaches, an introduction to the efficient FSI formulation, comparison of the presented FSI method with higher-fidelity simulation methods, demonstrations of the method's capability for tradeoff and optimization studies, and an overview of contributions to a nonlinear dynamic algorithm for the simulation of flapping flight.

Combes, Thomas P.

413

Mars Lander/Rover vehicle development: An advanced space design project for USRA and NASA/OAST  

NASA Technical Reports Server (NTRS)

The results of the studies on one particular part of the Mars Lander/Rover (MLR) system are contained: the Balloon Rover. This component vehicle was selected for further research and design because of the lack of technical literature on this subject, as compared to surface rover technology. Landing site selection; balloon system development and deployment; optics and communications; and the payload power supply are described.

1987-01-01

414

A semi-active suspension design for off-road vehicle base on Magneto-rheological technology  

Microsoft Academic Search

In this paper, a Magneto-Rheological (MR) fluid semi-active suspension system was tested on a off-road vehicle to determine the performance improvements compared to passive suspensions. In the process of suspension design, ride comfort and handing stability are two conflicting considerations. MR fluid dampers are a new class of devices that more suitable for the requirements of automotive applications, including having

Long-ming Gui; Wen-ku Shi; Wei Liu

2012-01-01

415

System design of an unmanned aerial vehicle (UAV) for marine environmental sensing  

E-print Network

Technological improvements over the past decade have led to the widespread use of autonomous surface and underwater vehicles for data collection in marine environmental sensing and modeling in coastal environments. However, ...

Leighton, Joshua (Joshua C.)

2013-01-01

416

Design of a spherical vehicle with flywheel momentum storage for high torque capabilities  

E-print Network

A novel method for supplementing the propulsion of a spherical ground vehicle was conceived and developed. The addition of angular momentum storage via counter-rotating control moment gyroscopes is proposed in order to ...

Schroll, Gregory C. (Gregory Cordner)

2008-01-01

417

Marine Vehicle Sensor Network Architecture and Protocol Designs for Ocean Observation  

PubMed Central

The micro-scale and meso-scale ocean dynamic processes which are nonlinear and have large variability, have a significant impact on the fisheries, natural resources, and marine climatology. A rapid, refined and sophisticated observation system is therefore needed in marine scientific research. The maneuverability and controllability of mobile sensor platforms make them a preferred choice to establish ocean observing networks, compared to the static sensor observing platform. In this study, marine vehicles are utilized as the nodes of mobile sensor networks for coverage sampling of a regional ocean area and ocean feature tracking. A synoptic analysis about marine vehicle dynamic control, multi vehicles mission assignment and path planning methods, and ocean feature tracking and observing techniques is given. Combined with the observation plan in the South China Sea, we provide an overview of the mobile sensor networks established with marine vehicles, and the corresponding simulation results. PMID:22368475

Zhang, Shaowei; Yu, Jiancheng; Zhang, Aiqun; Yang, Lei; Shu, Yeqiang

2012-01-01

418

Design, construction and performance of an EMS-based HTS maglev vehicle  

Microsoft Academic Search

A laboratory-scale EMS-based HTS maglev vehicle operating over a 1.5m guideway has been successfully constructed. The fully integrated system consists of a vehicle chassis, four dependent magnetic circuits, four distance sensors, and control and power amplification circuits. As key component of the system, each magnetic circuit includes a U-shape iron core with one HTS coil forming each pole. Eight HTS

Chen Gu; Menglin Liu; Huawei Xing; Tong Zhou; Wensheng Yin; Jun Zong; Zhenghe Han

2005-01-01

419

Design of a Web-based Decision Support System for End-of-Life Vehicles  

Microsoft Academic Search

Decision Support Systems (DSS) have been involved in all of the stages of the products life-cycle. In the business of end-of-life vehicles (ELVs) treatment, once PEID (Product Embedded Information Devices) systems are used to collect all life-cycle data of the vehicles, a DSS could be needed to manipulate the information and help the operator optimizing the decision results during the

Hui Cao

420

Design of a Permanent Magnet Synchronous Machine for a Flywheel Energy Storage System within a Hybrid Electric Vehicle  

NASA Astrophysics Data System (ADS)

As an energy storage device, the flywheel has significant advantages over conventional chemical batteries, including higher energy density, higher efficiency, longer life time, and less pollution to the environment. An effective flywheel system can be attributed to its good motor/generator (M/G) design. This thesis describes the research work on the design of a permanent magnet synchronous machine (PMSM) as an M/G suitable for integration in a flywheel energy storage system within a large hybrid electric vehicle (HEV). The operating requirements of the application include wide power and speed ranges combined with high total system efficiency. Along with presenting the design, essential issues related to PMSM design including cogging torque, iron losses and total harmonic distortion (THD) are investigated. An iterative approach combining lumped parameter analysis with 2D Finite Element Analysis (FEA) was used, and the final design is presented showing excellent performance.

Jiang, Ming

421

Optimal Design of Integrated Systems Health Management (ISHM) Systems for improving safety in NASA's Exploration Vehicles: A Two-Level Multidisciplinary Design Approach  

NASA Technical Reports Server (NTRS)

Integrated Vehicle Health Management (ISHM) systems are used to detect, assess, and isolate functional failures in order to improve safety of space systems such as Orbital Space Planes (OSPs). An ISHM system, as a whole, consists of several subsystems that monitor different components of an OSP including: Spacecraft, Launch Vehicle, Ground Control, and the International Space Station. In this research, therefore, we propose a new methodology to design and optimize ISHM as a distributed system with multiple disciplines (that correspond to different subsystems of OSP safety). A paramount amount of interest has been given in the literature to the multidisciplinary design optimization of problems with such architecture (as will be reviewed in the full paper).

Mehr, Ali Farhang; Tumer, Irem; Barszcz, Eric

2005-01-01

422

System design optimization for a Mars-roving vehicle and perturbed-optimal solutions in nonlinear programming  

NASA Technical Reports Server (NTRS)

Work in two somewhat distinct areas is presented. First, the optimal system design problem for a Mars-roving vehicle is attacked by creating static system models and a system evaluation function and optimizing via nonlinear programming techniques. The second area concerns the problem of perturbed-optimal solutions. Given an initial perturbation in an element of the solution to a nonlinear programming problem, a linear method is determined to approximate the optimal readjustments of the other elements of the solution. Then, the sensitivity of the Mars rover designs is described by application of this method.

Pavarini, C.

1974-01-01

423

Design of integrated autopilot/autothrottle for NASA TSRV airplane using integral LQG methodology. [transport systems research vehicle  

NASA Technical Reports Server (NTRS)

An integrated autopilot/autothrottle control system has been developed for the NASA transport system research vehicle using a two-degree-of-freedom approach. Based on this approach, the feedback regulator was designed using an integral linear quadratic regulator design technique, which offers a systematic approach to satisfy desired feedback performance requirements and guarantees stability margins in both control and sensor loops. The resulting feedback controller was discretized and implemented using a delta coordinate concept, which allows for transient free controller switching by initializing all controller states to zero and provides a simple solution for dealing with throttle limiting cases.

Kaminer, Isaac; Benson, Russell A.

1989-01-01

424

High voltage energy storage system design for a parallel-through-the-road plug-in hybrid electric vehicle  

NASA Astrophysics Data System (ADS)

A parallel-through-the-road (PTTR) plug-in hybrid electric vehicle (PHEV) pairs an engine powering the front wheels of a vehicle with an electric motor powering the rear wheels. This arrangement gives the flexibility of being able to operate the vehicle in an all-electric mode, an all biodiesel mode, or a combination of both to create maximum power. For this work, a 1.7 L CIDI engine running on biodiesel will be the engine being used and a 103 kW Magna motor will power the rear wheels. In order to power the motor, a high voltage (HV) energy storage system (ESS) needs to be designed and integrated into the vehicle. The goal for the mechanical design of the ESS is to create a structure that will enclose all of the batteries and battery control modules to protect them from environmental factors such as dirt and water as well as to prevent them from becoming dislodged in the event of a collision. The enclosure will also serve as a means to protect the consumer from the dangers of HV. The mechanical design also entailed designing a cooling system that will keep the batteries operating in an acceptable temperature range while they are charging and discharging. The electrical design focused on designing a HV system that could adequately supply enough current flow to each component to meet the peak loading condition yet be able to disconnect should a fault occur to prevent component damage. The system was also designed with safety in mind. Controllers will constantly be monitoring both the HV and LV systems to make sure that each is isolated from the other. Should a controller detect a problem, it will disconnect the HV system. The electrical system will have a high voltage interlock loop (HVIL). The HVIL will be a continuous LV circuit that passes through every HV connector and various switches, so that, if a connector is unplugged or a switch is flipped, the circuit will open. A controller will be monitoring the HVIL for LV. Should it not detect LV, the controller will disconnect the HV system. Several simulations and calculations were conducted as to whether six or seven batteries should be used. Seven batteries will allow the vehicle to accelerate quicker and have lower fuel consumption and emissions produced. However, there are several integration and cooling challenges that arise when trying to integrate seven batteries onto the vehicle. In the end, these challenges outweighed the benefits of seven batteries, and the six battery system was chosen. On top of all of the design and simulation results discussed above, there were also many lessons learned in regards to managing the design team involved in this project. The best way found to keep all members on task was to split the project into smaller sections, create a timeline with specific tasks and corresponding completion dates, and assign a person to be responsible for each task. This helped to gauge whether the project was behind schedule but also gave each member a responsibility and ownership to the project. It was also established that the best way to transmit data was to have a secure, networked drive that allowed members to access it from any computer at any time. This gave members the flexibility to work whenever and wherever was most convenient for them and allowed them to easily share data amongst members without having to attach large files to emails.

Belt, Bryan Whitney D.

425

Assessment and preliminary design of an energy buffer for regenerative braking in electric vehicles  

NASA Technical Reports Server (NTRS)

Energy buffer systems, capable of storing the vehicle energy during braking and reusing this stored energy during acceleration, were examined. Some of these buffer systems when incorporated in an electric vehicle would result in an improvement in the performance and range under stop and go driving conditions. Buffer systems considered included flywheels, hydropneumatic, pneumatic, spring, and regenerative braking. Buffer ranking and rating criteria were established. Buffer systems were rated based on predicted range improvements, consumer acceptance, driveability, safety, reliability and durability, and initial and life cycle costs. A hydropneumatic buffer system was selected.

Buchholz, R.; Mathur, A. K.

1979-01-01

426

22 CFR 121.4 - Ground vehicles.  

...2) Are armored support vehicles capable of off-road or amphibious use specially...Ground vehicles include any vehicle meeting the definitions...surface (e.g., highway, off-road, rail) upon which the vehicle is designed to...

2014-04-01

427

Optimal design of hybrid and non-hybrid fuel cell vehicles  

E-print Network

as an alternative power source for automobiles, because of their clean and efficient power production. This emerging technology, however, still has many issues to be addressed for market acceptance. Several fuel cell vehicle power generation. Therefore, an optimal control strategy also needs to be taken into account

Papalambros, Panos

428

Hybrid Kalman\\/H?filter in designing optimal navigation of vehicle in PRT System  

Microsoft Academic Search

PRT( Personal Rapid Transit ) system is a automated operation, so that it is important exactly finding position of vehicle. Many of PRT system has accepted the GPS system for a position, speed, and direction. in this paper, we propose a combination of Kalman Filter and H? Filter known as Hybrid Kalman\\/ H? Filter for applying to GPS navigation algorithm.

Hyunsoo Kim; Hoang Hieu Nguyen; Phi Long Nguyen; Han Sil Kim; Young Hwan Jang; Myungseon Ryu; Changho Choi

2007-01-01

429

DESIGN AND DEVELOPMENT OF A MICRO AIR VEHICLE (AV) CONCEPT: PROJECT BIDULE  

E-print Network

to the wing loading and a high maximum lift. The wind tunnel testing of a propelled model of the "Bidule, propeller effects, wind tunnel. Introduction The concept of micro-sized Unmanned Aerial Vehicles (UAVs immersed in a propeller slipstream, providing that the destabilising effects due to the power system

Wong, K. C.

430

Platform-Based Embedded Software Design and System Integration for Autonomous Vehicles  

E-print Network

.2002.805827 increase in capabilities of integrated circuit technology and the advances in control about the control of vehicles, such as airplanes and cars, and about the control of armaments, has led, IEEE, AND S. SHANKAR SASTRY, FELLOW, IEEE Invited Paper Automatic control systems typically incorporate

Sastry, S. Shankar

431

Optimal Design and Allocation of Electrified Vehicles and Dedicated Charging Infrastructure for Minimum Greenhouse Gas Emissions  

E-print Network

for Minimum Greenhouse Gas Emissions Submitted for Presentation at the 2011 Annual Meeting to reduce greenhouse gas (GHG) emissions from personal transportation by shifting energy demand from in the fleet for minimum lifecycle GHG emissions over a range of scenarios. We focus on vehicles with similar

Michalek, Jeremy J.

432

HARBOR BRANCH OCEANOGRAPHIC INSTITUTE scientists and engineers design and build tools, instruments, and vehicles  

E-print Network

, instruments, and vehicles for coastal and ocean research, develop sustainable systems for seafood production, and discover life saving drugs. EXPLORATION The need to know more about our oceans has led Harbor Branch researchers to explore and discover habitats and species, using our ship and submersibles, throughout

Fernandez, Eduardo

433

Autonomous Controller Design for Unmanned Aerial Vehicles using Multi-objective Genetic  

E-print Network

simulations and used multi- objective GP to evolve controllers able to locate a radar source, navigate the UAV-- Autonomous navigation controllers were developed for fixed wing unmanned aerial vehicle (UAV) applications were evolved for three different kinds of radars: stationary, continuously emitting radars, stationary

Fernandez, Thomas

434

Hover and wind-tunnel testing of shrouded rotors for improved micro air vehicle design  

NASA Astrophysics Data System (ADS)

The shrouded-rotor configuration has emerged as the most popular choice for rotary-wing Micro Air Vehicles (MAVs), because of the inherent safety of the design and the potential for significant performance improvements. However, traditional design philosophies based on experience with large-scale ducted propellers may not apply to the low-Reynolds-number (20,000) regime in which MAVs operate. An experimental investigation of the effects of varying the shroud profile shape on the performance of MAV-scale shrouded rotors has therefore been conducted. Hover tests were performed on seventeen models with a nominal rotor diameter of 16 cm (6.3 in) and various values of diffuser expansion angle, diffuser length, inlet lip radius and blade tip clearance, at various rotor collective angles. Compared to the baseline open rotor, the shrouded rotors showed increases in thrust by up to 94%, at the same power consumption, or reductions in power by up to 62% at the same thrust. These improvements surpass those predicted by momentum theory, due to the additional effect of the shrouds in reducing the non-ideal power losses of the rotor. Increasing the lip radius and decreasing the blade tip clearance caused performance to improve, while optimal values of diffuser angle and length were found to be 10 and 50% of the shroud throat diameter, respectively. With the exception of the lip radius, the effects of changing any of the shrouded-rotor parameters on performance became more pronounced as the values of the other parameters were changed to degrade performance. Measurements were also made of the wake velocity profiles and the shroud surface pressure distributions. The uniformity of the wake was improved by the presence of the shrouds and by decreasing the blade tip clearance, resulting in lower induced power losses. For high net shroud thrust, a favorable pressure distribution over the inlet was seen to be more important than in the diffuser. Strong suction pressures were observed above the blade-passage region on the inlet surface; taking advantage of this phenomenon could enable further increases in thrust. However, trade studies showed that, for a given overall aircraft size limitation, and ignoring considerations of the safety benefits of a shroud, a larger-diameter open rotor is more likely to give better performance than a smaller-diameter shrouded rotor. The open rotor and a single shrouded-rotor model were subsequently tested at a single collective in translational flight, at angles of attack from 0 (axial flow) to 90 (edgewise flow), and at various advance ratios. In axial flow, the net thrust and the power consumption of the shrouded rotor were lower than those of the open rotor. In edgewise flow, the shrouded rotor produced greater thrust than the open rotor, while consuming less power. Measurements of the shroud surface pressure distributions illustrated the extreme longitudinal asymmetry of the flow around the shroud, with consequent pitch moments much greater than those exerted on the open rotor. Except at low airspeeds and high angles of attack, the static pressure in the wake did not reach ambient atmospheric values at the diffuser exit plane; this challenges the validity of the fundamental assumption of the simple-momentum-theory flow model for short-chord shrouds in translational flight.

Pereira, Jason L.

435

Design and implementation of an early warning system in vehicle for road speed control hump based on DSP and CCD  

NASA Astrophysics Data System (ADS)

Road speed control humps have the effect of strengthening transportation safety by preventing traffic accidents. However, vehicles will produce strong mechanical vibrations when crossing speed control humps at high speed. These vibrations affect the passenger's comfort and cause machine parts damage. Early warning systems in vehicles for road speed control humps were designed based on DSP and CCD sensors. The system uses a CCD camera to take the picture of the road speed control humps. The image information is processed and recognised by DSP. Then the related voice and image information is given quickly and accurately after the system processes. This information will remind the driver to prepare for slowing down in good time, it makes them safe and comfortable to pass over the road speed control hump.TMS320DM642DSP early warning system in vehicles was illustrated from three aspects of the image collection module, the image discernment module and the early warning export module. TMS320C6x soft develop flow was introduced in this paper. The system has strong practicality, rapid response and well directed-viewing.

Yang, Shuyi; Zhu, Pingyu; He, Yanfang; Wang, Le

2011-12-01

436

Design studies of large aperture, high-resolution Earth science microwave radiometers compatible with small launch vehicles  

NASA Technical Reports Server (NTRS)

High-spatial-resolution microwave radiometer sensing from space with reasonable swath widths and revisit times favors large aperture systems. However, with traditional precision antenna design, the size and weight requirements for such systems are in conflict with the need to emphasize small launch vehicles. This paper describes tradeoffs between the science requirements, basic operational parameters, and expected sensor performance for selected satellite radiometer concepts utilizing novel lightweight compactly packaged real apertures. Antenna, feed, and radiometer subsystem design and calibration are presented. Preliminary results show that novel lightweight real aperture coupled with state-of-the-art radiometer designs are compatible with small launch systems, and hold promise for high-resolution earth science measurements of sea ice, precipitation, soil moisture, sea surface temperature, and ocean wind speeds.

Schroeder, Lyle C.; Bailey, M. C.; Harrington, Richard F.; Kendall, Bruce M.; Campbell, Thomas G.

1994-01-01

437

Modeling and inverse controller design for an unmanned aerial vehicle based on the self-organizing map.  

PubMed

The next generation of aircraft will have dynamics that vary considerably over the operating regime. A single controller will have difficulty to meet the design specifications. In this paper, a self-organizing map (SOM)-based local linear modeling scheme of an unmanned aerial vehicle (UAV) is developed to design a set of inverse controllers. The SOM selects the operating regime depending only on the embedded output space information and avoids normalization of the input data. Each local linear model is associated with a linear controller, which is easy to design. Switching of the controllers is done synchronously with the active local linear model that tracks the different operating conditions. The proposed multiple modeling and control strategy has been successfully tested in a simulator that models the LoFLYTE UAV. PMID:16566471