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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

Road load simulator tests of the Gould phase 1 functional model silicon controlled rectifier ac motor controller for electric vehicles

The test results for a functional model ac motor controller for electric vehicles and a three-phase induction motor which were dynamically tested on the Lewis Research Center road load simulator are presented. Results show that the controller has the capability to meet the SAE-J227a D cycle test schedule and to accelerate a 1576-kg (3456-lb) simulated vehicle to a cruise speed of 88.5 km/hr (55 mph). Combined motor controller efficiency is 72 percent and the power inverter efficiency alone is 89 percent for the cruise region of the D cycle. Steady state test results for motoring, regeneration, and thermal data obtained by operating the simulator as a conventional dynamometer are in agreement with the contractor's previously reported data. The regeneration test results indicate that a reduction in energy requirements for urban driving cycles is attainable with regenerative braking. Test results and data in this report serve as a data base for further development of ac motor controllers and propulsion systems for electric vehicles. The controller uses state-of-the-art silicon controlled rectifier (SCR) power semiconductors and microprocessor-based logic and control circuitry. The controller was developed by Gould Laboratories under a Lewis contract for the Department of Energy's Electric and Hybrid Vehicle program.

Gourash, F.↗
NASA NTRS1977

Baseline tests of the C. H. Waterman DAF electric passenger vehicle

An electric vehicle was tested as part of an Energy Research Development Administration (ERDA) project to characterize the state-of-the-art of electric vehicles. The Waterman vehicle performance test results are presented in this report. The vehicle is a converted four-passenger DAF 46 sedan. It is powered by sixteen 6-volt traction batteries through a three-step contactor controller actuated by a foot throttle to change the voltage applied to the 6.7 kW motor. The braking system is a conventional hydraulic braking system.

Sargent, N. B.↗
NASA NTRS1974

A remotely augmented vehicle approach to flight testing RPV control systems

A remotely augmented vehicle concept for flight testing advanced control systems was developed as an outgrowth of a remotely piloted research vehicle (RPV) program in which control laws are implemented through telemetry uplink and downlink data channels using a general purpose ground based digital computer which provides the control law computations. Some advantages of this approach are that the cost of one control system facility is spread over a number of RPV programs, and control laws can be changed quickly as required, without changing the flight hardware. The remotely augmented vehicle concept is described, and flight test results from a subscale F-15 program are discussed. Suggestions of how the concept could lead to more effective testing of RPV control system concepts, and how it is applicable to a military RPV reconnaissance mission are given.

Deets, D. A.↗
NASA NTRS2011

Orion Launch Abort Vehicle Attitude Control Motor Testing

Current Orion Launch Abort Vehicle (LAV) configurations use an eight-jet, solid-fueled Attitude Control Motor (ACM) to provide required vehicle control for all proposed abort trajectories. Due to the forward position of the ACM on the LAV, it is necessary to assess the effects of jet-interactions (JI) between the various ACM nozzle plumes and the external flow along the outside surfaces of the vehicle. These JI-induced changes in flight control characteristics must be accounted for in developing ACM operations and LAV flight characteristics. A test program to generate jet interaction aerodynamic increment data for multiple LAV configurations was conducted in the NASA Ames and NASA Langley Unitary Plan Wind Tunnels from August 2007 through December 2009. Using cold air as the simulant gas, powered subscale models were used to generate interaction data at subsonic, transonic, and supersonic test conditions. This paper presents an overview of the complete ACM JI experimental test program for Orion LAV configurations, highlighting ACM system modeling, nozzle scaling assumptions, experimental test techniques, and data reduction methodologies. Lessons learned are discussed, and sample jet interaction data are shown. These data, in conjunction with computational predictions, were used to create the ACM JI increments for all relevant flight databases.

Murphy, Kelly J.↗
NASA NTRS2002

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

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

Shams, Qamar A.↗
NASA NTRS1977

Baseline tests of the EPC Hummingbird electric passenger vehicle

The rear-mounted internal combustion engine in a four-passenger Volkswagen Thing was replaced with an electric motor made by modifying an aircraft generator and powered by 12 heavy-duty, lead-acid battery modules. Vehicle performance tests were conducted to measure vehicle maximum speed, range at constant speed, range over stop-and-go driving schedules, maximum acceleration, gradeability limit, road energy consumption, road power, indicated energy consumption, braking capability, battery charger efficiency, and battery characteristics. Test results are presented in tables and charts.

Slavik, R. J.↗
NASA NTRS2011

Challenges of CPAS Flight Testing

The Crew Exploration Vehicle Parachute Assembly System (CPAS) is being designed to land the Orion Crew Module (CM) at a safe rate of descent at splashdown via a series of Drogue, Pilot, and Main parachutes. Because Orion is considerably larger and heavier than Apollo, many of the flight test techniques developed during the Apollo program must be modified. The Apollo program had a dedicated C-133 aircraft, which was modified to allow a simple airdrop of "boilerplate" flight test vehicles. However, the CPAS program must use either commercial or military assets with minimal modifications to airframes or procedures. Conceptual envelopes from 2-Degree Of Freedom trajectories are presented for several existing and novel architectures. Ideally, the technique would deliver a representative capsule shape to the desired altitude and dynamic pressure at test initiation. However, compromises must be made on the characteristics of trajectories or the fidelity of test articles to production hardware. Most of the tests to date have used traditional pallet and weight tub or missile-shaped test vehicles. New test vehicles are being designed to better incorporate Orion structural components and deploy parachutes in a more representative fashion. The first attempt to test a capsule-shaped vehicle failed due to unexpected events while setting up the test condition through a series of complex procedures. In order to avoid the loss of another expensive test article which will delay the program, simpler deployment methods are being examined and more positive control of the vehicle will be maintained. Existing challenges include interfacing with parent aircraft, separating test vehicles, achieving test conditions, and landing within limited test ranges. All these challenges must be met within cost and schedule limits.

Ray, Eric S.↗
NASA NTRS1980

A laboratory facility for electric vehicle propulsion system testing

The road load simulator facility located at the NASA Lewis Research Center enables a propulsion system or any of its components to be evaluated under a realistic vehicle inertia and road loads. The load is applied to the system under test according to the road load equation: F(net)=K1F1+K2F2V+K3 sq V+K4(dv/dt)+K5 sin theta. The coefficient of each term in the equation can be varied over a wide range with vehicle inertial representative of vehicles up to 7500 pounds simulated by means of flywheels. The required torque is applied by the flywheels, a hydroviscous absorber and clutch, and a drive motor integrated by a closed loop control system to produce a smooth, continuous load up to 150 horsepower.

Sargent, N. B.↗
NASA NTRS1972

Performance, static stability, and control effectiveness of a parametric space shuttle launch vehicle

This test was run as a continuation of a prior investigation of aerodynamic performance and static stability tests for a parametric space shuttle launch vehicle. The purposes of this test were: (1) to obtain a more complete set of data in the transonic flight region, (2) to investigate new H-0 tank noseshapes and tank diameters, (3) to obtain control effectiveness data for the orbiter at 0 degree incidence and with a smaller diameter H-0 tank, and (4) to determine the effects of varying solid rocket motor-to-H0 tank gap size. Experimental data were obtained for angles of attack from -10 to +10 degrees and for angles of sideslip from +10 to -10 degrees at Mach numbers ranging from .6 to 4.96.

Buchholz, R. E.↗
NASA NTRS2009

Objectives and Progress on Ground Vibration Testing for the Ares Launch Vehicles

NASA has conducted dynamic tests on each of its major launch vehicles during the past 45 years. Each test has provided invaluable data to correlate and correct analytical models used to predict structural responses to differing dynamics for these vehicles. With both Saturn V and Space Shuttle, hardware changes were also required to the flight vehicles to ensure crew and vehicle safety. The Ares I IVGVT will undoubtedly provide similar valuable test data to support successful flights of the Constellation Program. The IVGVT will provide test determined natural frequencies, mode shapes and damping for the Ares I. This data will be used to support controls analysis by providing this test data to reduce uncertainty in the models. The value of this testing has been proven by past launch vehicle successes and failures. Performing dynamic testing on the Ares vehicles will provide confidence that the launch vehicles will be safe and successful in their missions. In addition, IVGVT will provide the following benefits for the Ares rockets: a) IVGVT data along with Ares development flights like Ares I-X, Ares I-Y, Ares I-X Prime, and Orion-1 or others will reduce the risk to the Orion-2 crew. IVGVT will permit anchoring the various analytical and operational models used in so many different aspects of Ares operations. b) IVGVT data will permit better understanding of the structural and GN&C margins of the spacecraft and may permit mass savings or expanded day-of-launch opportunities or fewer constraints to launch. c) Undoubtedly IVGVT will uncover some of the "unknown unknowns" so often seen in developing, launching, and flying new spacecraft vehicles and data from IVGVT may help prevent a loss of vehicle or crew. d) IVGVT also will be the first time Ares I flight-like hardware is transported, handled, rotated, mated, stacked, and integrated. e) Furthermore, handling and stacking the IVGVT launch vehicle stacks will be an opportunity to understand certain aspects of vehicle operability much better (for example, handling procedures, touch-labor time to accomplish tasks, access at interfaces, access to stage mating bolts, access to avionics boxes, access to the Interstage, GSE functionality, and many other important aspects of Ares I operability). All of these results will provide for better vehicle safety and better stewardship of national resources as NASA begins its next phase of human space exploration.

Tuma, Margaret L.↗
NASA NTRS1981

The DAST-1 remotely piloted research vehicle development and initial flight testing

The development and initial flight testing of the DAST (drones for aerodynamic and structural testing) remotely piloted research vehicle, fitted with the first aeroelastic research wing ARW-I are presented. The ARW-I is a swept supercritical wing, designed to exhibit flutter within the vehicle's flight envelope. An active flutter suppression system (FSS) designed to increase the ARW-I flutter boundary speed by 20 percent is described. The development of the FSS was based on prediction techniques of structural and unsteady aerodynamic characteristics. A description of the supporting ground facilities and aircraft systems involved in the remotely piloted research vehicle (RPRV) flight test technique is given. The design, specification, and testing of the remotely augmented vehicle system are presented. A summary of the preflight and flight test procedures associated with the RPRV operation is given. An evaluation of the blue streak test flight and the first and second ARW-I test flights is presented.

Kotsabasis, A.↗
NASA NTRSDate not supplied

Developing a Motion-Based System for Lunar Vehicle Handling Qualities Testing

— Motion and visual cue influences are critical in any simulator system, as they impact multiple aspects of the human’s neurovestibular and visual systems. Cues of real motion proceeds to the brain before cues of visual change. It is important therefore for simulator motion cues to exist and to match those realistically with those of the real vehicle to provide transferable training of the activity for operations. The United Kingdom’s Royal Air Force Institute of Aviation Medicine (1989)[1] stated that motion platforms are the only simulation devices capable of fully stimulating the body motion sensors. They confirmed that motion platforms can impart accelerations to the whole body and therefore exercise the automatic motion feedback-loop that operators are used to. With both visual and motion cues handling the vehicle becomes more realistic. Strachan (2019)[1] confirms motion cueing from a well set-up motion platform has been found to be important especially in conditions such as night or reduced visibility where motion cues may be more relied upon. As of this writing, the only lunar rover motion simulator is housed at the General Motors (GM) Milford Proving Ground, which only simulates the motions of a traditional car. A NASA Test Team proposed to complete a motion-based simulation system for NASA’s Lunar Terrain Vehicle (LTV) which resides at Johnson Space Center’s Systems Engineering Simulator facility. This activity integrated existing fixed base simulation capabilities with a newly procured six-degree of freedom motion base platform for the design, development, evaluation, and training associated with the LTV project. This would incorporate a South Pole Lunar virtual reality simulation using Lunar Reconnaissance Orbiter 5m/pixel high-resolution imagery and Unreal 5.2 Virtual Shadow Maps, combined with a virtual reality (VR) headset, integrated within a rover cockpit on a Mikrolar Motion Platform for evaluating human performance and vehicle handling qualities for concept roving vehicle designs. The motion-based system received its Human Rating Certification on March 2023. To begin testing the new facility, a preliminary handling qualities study was conducted. The objectives were to determine if there is a correlation amongst three handling quality methods of performance for a lunar vehicle and to understand the effects of a simulated 1/6-g loads and visuals with a motion platform on the operator while in a 1-g physical environment. The capability this system provides directly benefits the NASA’s Extravehicular Activity and Human Surface Mobility Program and NASA’s Flight Operations Directorate in evaluating the driving qualities of vehicle concepts, human performance related to the operating of a lunar surface vehicle, and assessment of suit related driving impacts. It would also provide direct operational benefit by providing a first-in class and unique simulation platform for the lunar astronaut training curriculum. The empirical knowledge of rover and human performance on this scale is paramount as there is currently no other lunar surface simulator with these capabilities. The result of this study ensures a broadly applicable method of testing for shirtsleeve, unpressurized and pressurized suited rover handling qualities.

Test Track↗
NASA NTRSDate not supplied

NASA Space Launch System Completes Key Hot Fire Test and Begins Vehicle Integration

NASA and its commercial and international partners are on the way back to the Moon. Significant progress towards that goal was made in 2021, including on the agency’s Space Launch System (SLS) rocket – a key part of the Artemis initiative. The SLS core stage for the Artemis I mission – the first launch of SLS and an uncrewed Orion capsule – completed its Green Run test series in early 2021 and was successfully mated with the SLS twin solid rocket boosters on the mobile launcher at Kennedy Space Center (KSC). The launch vehicle stage adapter, interim cryogenic propulsion stage, and the Orion stage adapter structural test article and Orion spacecraft mass simulator were also stacked. The flight Orion spacecraft and Orion stage adapter are being prepared for stacking and launch, targeted for late 2021 following a wet dress rehearsal at Launch Complex 39B. SLS hardware for Artemis II, which will be the first flight of crew on Orion and SLS, is also in work. Work progressed on core stage components, booster segments, and other hardware for Artemis III and future missions. This paper will detail the progress made.

John Honeycutt↗
NASA NTRS2017

Aerodynamic Coefficients from Aeroballistic Range Testing of Deployed- and Stowed-SIAD SFDT Models

This report documents a ballistic-range test campaign conducted in 2012 in order to estimate the aerodynamic stability characteristics of two configurations of the Supersonic Flight Dynamics Test (SFDT) vehicle prior to its initial flight in 2014. The SFDT vehicle was a test bed for demonstrating several new aerodynamic decelerator technologies then being developed under the Low-Density Supersonic Decelerator (LDSD) Project. Of particular interest here is the Supersonic Inflatable Aerodynamic Decelerator (SIAD), an inflatable attached torus used to increase the drag surface area of an entry vehicle during the supersonic portion of the entry trajectory. Two model configurations were tested in the ballistic range: one representing the SFDT vehicle prior to deployment of the SIAD, and the other representing the nominal shape with the SIAD inflated. Both models were fabricated from solid metal, and therefore, the effects of the flexibility of the inflatable decelerator were not considered. The test conditions were chosen to match, as close as possible, the Mach number, Reynolds number, and motion dynamics expected for the SFDT vehicle in flight, both with the SIAD stowed and deployed. For SFDT models with the SIAD stowed, 12 shots were performed covering a Mach number range of 3.2 to 3.7. For models representing the deployed SIAD, 37 shots were performed over a Mach number range of 2.0 to 3.8. Pitch oscillation amplitudes covered a range from 0.7 to 20.6 degrees RMS. Portions of this report (data analysis approach, aerodynamic modeling, and resulting aerodynamic coefficients) were originally published as an internal LDSD Project report [1] in 2012. In addition, this report provides a description of the test design approach, the test facility, and experimental procedures. Estimated non-linear aerodynamic coefficients, including pitch damping, for both model configurations are reported, and the shot-by-shot trajectory measurements, plotted in comparison with calculated trajectories based on the derived non-linear aerodynamic coefficients, are provided as appendices. Since the completion of these tests, two full-scale SFDT flights have been successfully conducted: one in June 2014 [2, 3], and one in June 2015 [3].

Ground Test↗