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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 1,513 records · Page 84
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

Launching to the Moon, Mars, and Beyond

America is returning to the Moon in preparation for the first human footprint on Mars, guided by the U.S. Vision for Space Exploration. This presentation will discuss NASA's mission today, the reasons for returning to the Moon and going to Mars, and how NASA will accomplish that mission. The primary goals of the Vision for Space Exploration are to finish the International Space Station, retire the Space Shuttle, and build the new spacecraft needed to return people to the Moon and go to Mars. Unlike the Apollo program of the 1960s, this phase of exploration will be a journey, not a race. In 1966, the NASA's budget was 4 percent of federal spending. Today, with 6/10 of 1 percent of the budget, NASA must incrementally develop the vehicles, infrastructure, technology, and organization to accomplish this goal. Fortunately, our knowledge and experience are greater than they were 40 years ago. NASA's goal is a return to the Moon by 2020. The Moon is the first step to America's exploration of Mars. Many questions about the Moon's history and how its history is linked to that of Earth remain even after the brief Apollo explorations of the 1960s and 1970s. This new venture will carry more explorers to more diverse landing sites with more capable tools and equipment. The Moon also will serve as a training ground in several respects before embarking on the longer, more perilous trip to Mars. The journeys to the Moon and Mars will require a variety of vehicles, including the Ares I Crew Launch Vehicle, the Ares V Cargo Launch Vehicle, the Orion Crew Exploration Vehicle, and the Lunar Surface Access Module. The architecture for the lunar missions will use one launch to ferry the crew into orbit on the Ares I and a second launch to orbit the lunar lander and the Earth Departure Stage to send the lander and crew vehicle to the Moon. In order to reach the Moon and Mars within a lifetime and within budget, NASA is building on proven hardware and decades of experience derived from the Apollo Saturn, Space Shuttle, and contemporary commercial launch vehicle programs. Less than one year after the Exploration Launch Projects Office was formed at NASA's Marshall Space Flight Center, engineers are testing engine components, firing test rocket motors, refining vehicle designs in wind tunnel tests, and building hardware for the first flight test of Ares I, scheduled for spring 2009. The Vision for Exploration will require this nation to develop tools, machines, materials, and processes never before invented, technologies and capabilities that can be turned over to the private sector to benefit nearly all aspects of life on Earth. This new pioneering venture, as did the Apollo Program before it, will contribute to America's economic leadership, national security, and technological global competitiveness and serve as an inspiration for all its citizens.

Sumrall, John P.↗
NASA NTRS1999

Testing of the International Space Station and X-38 Crew Return Vehicle GPS Receiver

This paper discusses the process and results of the performance testing of the GPS receiver planned for use on the International Space Station (ISS) and the X- 38CrewReturnVehicle(CRV). The receiver is a Force-19 unit manufactured by Trimble Navigation and modified in software by NASA:s Goddard Space Flight Center (GSFC) to perform navigation and attitude determination in space. The receiver is the primary source of navigation and attitude information for ISS and CRV. Engineers at GSFC have developed and tested the new receiver with a Global Simulation Systems Ltd (GSS) GPS Signal Generator (GPSSG). This paper documents the unique aspects of ground testing a GPS receiver that is designed for use in space. A discussion of the design of tests using the GPSSG, documentation, data capture, data analysis, and lessons learned will precede an overview of the performance of the new receiver. A description of the challenges that were overcome during this testing exercise will be presented. Results from testing show that the receiver will be within or near the specifications for ISS attitude and navigation performance. The process for verifying other requirements such as Time to First Fix, Time to First Attitude, selection/deselection of a specific GPS satellite vehicles (SV), minimum signal strength while still obtaining attitude and navigation, navigation and attitude output coverage, GPS week rollover, and Y2K requirements are also given in this paper.

Simpson, James↗
NASA NTRS2016

Absolute Navigation Performance of the Orion Exploration Fight Test 1

Launched in December 2014 atop a Delta IV Heavy from the Kennedy Space Center, the Orion vehicle's Exploration Flight Test-1 (EFT-1) successfully completed the objective to stress the system by placing the un-crewed vehicle on a high-energy parabolic trajectory replicating conditions similar to those that would be experienced when returning from an asteroid or a lunar mission. Unique challenges associated with designing the navigation system for EFT-1 are presented with an emphasis on how redundancy and robustness influenced the architecture. Two Inertial Measurement Units (IMUs), one GPS receiver and three barometric altimeters (BALTs) comprise the navigation sensor suite. The sensor data is multiplexed using conventional integration techniques and the state estimate is refined by the GPS pseudorange and deltarange measurements in an Extended Kalman Filter (EKF) that employs UDU factorization. The performance of the navigation system during flight is presented to substantiate the design.

Zanetti, Renato↗
DOE OSTI2023

Design and testing of an enriched uranium fueled molten salt irradiation vehicle

Molten salt reactors (MSRs) have garnered increasing attention recently with several demonstration efforts on the way. A key challenge to the licensing basis for these reactors is the lack of experimental data on fueled salts. This is expected to be crucial to the safety evaluation and licensing basis of reactors of this type deployed in the future. While capability for irradiating molten salts has started being reestablished in the recent decade, no enriched fuel irradiation capability has been developed and tested as of yet. A new experiment vehicle under development at Idaho National Laboratory (INL) is presented here. The Molten-salt Research Temperature-controlled Irradiation (MRTI) experiment was developed to host enriched-uranium bearing salt samples to be irradiated at a test reactor within the lab complex. One of the key scientific objectives is to provide irradiated salt samples for post irradiation examination (PIE) to study the impact of fission product generation and neutron/gamma radioactivity on the salt solution and salt-facing wall material. This paper provides a detailed overview of the mechanical design of the experiment, followed by an overview of the fabrication and assembly of an initial prototype vehicle (with non-fuel bearing salt). A summary of the key analyses conducted as a part of the performance and safety evaluation is then provided. Lastly, an overview of the test conducted in prototypic out-of-pile (non-neutron) environment are shown. These evaluations provide the foundation for a planned irradiation of and enriched uranium-bearing chloride salt sample in the near term. The upcoming irradiation will contain 13cm 3 of UCl 3 -NaCl salt (93% enrichment) generating around 20 W/cm 3 of fission energy during irradiation and a temperature range that can be contained between bounds of 525-900°C.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1978

Structural concepts and experimental considerations for a versatile high-speed research airplane

Future aircraft may be hydrogen fueled and fly at hypersonic speeds. The resulting environments will require new structural concepts to satisfy performance goals. Large representative structures will have to be flight tested prior to commitment to a costly vehicle fleet. To perform flight tests, a versatile, economical, high-speed research airplane is defined. Results of this study including experimental considerations for a hypersonic research airplane are reported.

Jackson, L. R.↗
NASA NTRS2000

Salient Characteristics for Terrestrial Analog Engineering Test Sites

The use of terrestrial analog sites is an essential component of the development process for systems that are planned for lunar and planetary surfaces. These sites can also be valuable for training personnel who are expected to operate those systems. The fact that the site is an integral element, capable of influencing data and impacting test results, must not be overlooked. For tests performed in analog environments to be truly valid it is essential that the relevant characteristics of the employed sites be thoroughly understood. It is also critical that a comparative evaluation be made to assess the similarity of the analog sites to target planetary sites. Examples of relevant characteristics include terrain, soil properties, meteorology, geologic features, biological history, and remoteness. The importance of each of the characteristics varies with the type of extraterrestrial activity to be conducted. As a result, a site that is ideal for one purpose may be totally inadequate for another. It may also be appropriate to utilize multiple sites of increasing fidelity as the development process evolves. For example, early in the development process, the use of lower-fidelity sites may be elected - especially if they are available for a lower cost. Later, it may be necessary to employ higher-fidelity sites to capture greater realism, even if there is an associated increased cost. Finally, when interpreting the results of field tests, it is necessary to understand the sensitivity of the results to the relevant conditions. Knowledge of characteristics and sensitivity of results is particularly important when using field test results to validate analytical model predictions. This is especially true for activities that involve physical interaction with the site. Examples would include tests of rovers or other vehicles and associated trafficability modeling, spacesuit mobility tests, and tests associated with system deployment operations.

Watson, J.K.↗
NASA NTRS2006

Free Enterprise: Contributions of the Approach and Landing Test (ALT) Program to the Development of the Space Shuttle Orbiter

The space shuttle orbiter was the first spacecraft designed with the aerodynamic characteristics and in-atmosphere handling qualities of a conventional airplane. In order to evaluate the orbiter's flight control systems and subsonic handling characteristics, a series of flight tests were undertaken at NASA Dryden Flight Research Center in 1977. A modified Boeing 747 Shuttle Carrier Aircraft carried the Enterprise, a prototype orbiter, during eight captive tests to determine how well the two vehicles flew together and to test some of the orbiter s systems. The free-flight phase of the ALT program allowed shuttle pilots to explore the orbiter's low-speed flight and landing characteristics. The Enterprise provided realistic, in-flight simulations of how subsequent space shuttles would be flown at the end of an orbital mission. The fifth free flight, with the Enterprise landing on a concrete runway for the first time, revealed a problem with the space shuttle flight control system that made it susceptible to pilot-induced oscillation, a potentially dangerous control problem. Further research using various aircraft, particularly NASA Dryden's F-8 Digital-Fly-By-Wire testbed, led to correction of the problem before the first Orbital Test Flight.

Merlin, Peter W.↗
NASA NTRS2015

Active Structural Control for Aircraft Efficiency with the X-56A Aircraft

The X-56A Multi-Utility Technology Testbed is an experimental aircraft designed to study active control of flexible structures. The vehicle is easily reconfigured to allow for testing of different configurations. The vehicle is being used to study new sensor, actuator, modeling and controls technologies. These new technologies will allow for lighter vehicles and new configurations that exceed the efficiency currently achievable. A description of the vehicle and the current research efforts that it enables are presented.

aeroservoelasticity↗
NASA NTRS2010

TPSAS-NF1676L-11132-DND

The Orion Pad Abort 1 Flight Test occurred on May 6th, 2010 at White Sands Missile Range in New Mexico. The test was the first for the Orion vehicle and was primarily a test of the Orion Launch Abort System’s ability to execute an abort from the launch pad. The test was successful, and, in most cases, results were well within predicted outcomes. For this test, the thermal control subsystem was an inherent part of the flight operations team. The thermal team provided pre-launch predictions of component temperatures, set component temperature limits, and monitored those limits during the flight operations process as part of the primary flight operations team. The thermal team was also responsible for day-of-flight predictions of the main abort motor’s propellant mean bulk temperature, a key launch constraint for the test. After the test, thermal data was collected, reviewed, and compared against pre-launch predictions showing very good agreement in most areas. Based on the pre-test and flight operations experience, a detailed list of lessons learned has been developed and will be reviewed prior to potential future Orion or other such flight tests.

Joseph F Gasbarre↗
NASA NTRSDate not supplied

TPSAS-NF1676L-11021-DND

The Orion Pad Abort 1 Flight Test occurred on May 6th, 2010 at White Sands Missile Range in New Mexico. The test was the first for the Orion vehicle and was primarily a test of the Orion Launch Abort System’s ability to execute an abort from the launch pad. The test was successful and in most cases results were well within predicted outcomes. For this test, the thermal control subsystem was an inherent part of the flight operations team. The thermal team provided pre-launch predictions of component temperatures, set component temperature limits, and monitored those limits during the flight operations process as part of the primary flight operations team. The thermal team was also responsible for day-of-flight predictions of the main abort motor’s propellant mean bulk temperature, a key launch constraint for the test. After the test, thermal data was collected, reviewed, and compared against pre-launch predictions showing very good agreement in most areas. Based on the pre-test and flight operations experience, a detailed list of lessons learned has been developed and will be reviewed prior to potential future Orion or other such flight tests.

Joseph F Gasbarre↗
NASA NTRS1976

Determination of subcritical damping by moving-block/randomdec applications

Two techniques are described which allow the determination of subcritical dampings and frequencies during aeroelastic testing of flight vehicles. The moving-block technique is shown to have the advantage of being able to provide damping and frequency information for each mode which might be present in a signal trace, but it has the disadvantage of requiring that the structure be excited transiently. The randomdec technique requires only random turbulence for excitation, but the randomdec signature is difficult to analyze when more than one mode is present. It is shown that by using the moving-block technique to analyze the randomdec signatures, the best features of both methods are gained. Examples are presented illustrating the direct application of the moving-block method to model helicopter rotor testing and application of the combined moving-block/randomdec method to flutter studies of two fixed-wing models.

Hammond, C. E.↗
NASA NTRS1989

Techniques for extreme attitude suspension of a wind tunnel model in a magnetic suspension and balance system

Although small scale magnetic suspension and balance systems (MSBSs) for wind tunnel use have been in existence for many years, they have not found general application in the production testing of flight vehicles. One reason for this is thought to lie in the relatively limited range of attitudes over which a wind tunnel model may be suspended. Modifications to a small MSBS to permit the suspension and control of axisymmetric models over angles of attack from less than zero to over ninety degrees are reported. Previous work has shown that existing arrangement of ten electromagnets was unable to generate one of the force components needed for control at extreme attitudes. Examination of possible solutions resulted in a simple alteration to rectify this deficiency. To generate the feedback signals to control the suspended model, an optical position sensing system using collimated laser beams and photodiode arrays was installed and tested. An analytical basis was developed for distributing the demands for force and moment needed for model stabilization amonge the electromagnets over the full attitude range. This was implemented by an MSBS control program able to continually adjust the distribution for the instantaneous incidence in accordance with prescheduled data. Results presented demonstrate rotations of models from zero to ninety degrees at rates up to ninety degrees per second, with pitching rates rising to several hundred degrees per second in response to step-change demands. A study of a design for a large MSBS suggests that such a system could be given the capability to control a model in six degrees of freedom over an unlimited angle of attack range.

Parker, David Huw↗
NASA NTRS2012

Global Infrared Observations of Roughness Induced Transition on the Space Shuttle Orbiter

High resolution infrared observations made from a mobile ground based optical system captured the laminar-to-turbulent boundary layer transition process as it occurred during Space Shuttle Endeavour's return to earth following its final mission in 2011. The STS-134 imagery was part of a larger effort to demonstrate an emerging and reliable non-intrusive global thermal measurement capability and to complement a series of boundary layer transition flight experiments that were flown on the Shuttle. The STS-134 observations are believed to be the first time that the development and movement of a hypersonic boundary layer transition front has been witnessed in flight over the entire vehicle surface and in particular, at unprecedented spatial resolution. Additionally, benchmark surface temperature maps of the Orbiter lower surface collected over multiple flights and spanning a Mach range of 18 to 6 are now available and represent an opportunity for collaborative comparison with computational techniques focused on hypersonic transition and turbulence modeling. The synergy of the global temperature maps with the companion in-situ thermocouple measurements serve as an example of the effective leveraging of resources to achieve a common goal of advancing our understanding of the complex nature of high Mach number transition. It is shown that quantitative imaging can open the door to a multitude of national and international opportunities for partnership associated with flight-testing and subsequent validation of numerical simulation techniques. The quantitative imaging applications highlighted in this paper offer unique and complementary flight measurement alternatives and suggest collaborative instrumentation opportunities to advance the state of the art in transition prediction and maximize the return on investment in terms of developmental flight tests for future vehicle designs.

Horvath, Thomas J.↗
NASA NTRS1975

Manned Systems Utilization Analysis. Study 2.1: Space Servicing Pilot Program Study

Space servicing automated payloads was studied for potential cost benefits for future payload operations. Background information is provided on space servicing in general, and on a pilot flight test program in particular. An fight test is recommended to demonstrate space servicing. An overall program plan is provided which builds upon the pilot program through an interim servicing capability. A multipayload servicing concept for the time when the full capability tug becomes operational is presented. The space test program is specifically designed to provide low-cost booster vehicles and a flight test platform for several experiments on a single flight.

Wolfe, R. R.↗
NASA NTRS2010

Human Factors Evaluations of Two-Dimensional Spacecraft Conceptual Layouts

Much of the human factors work done in support of the NASA Constellation lunar program has been with low fidelity mockups. These volumetric replicas of the future lunar spacecraft allow researchers to insert test subjects from the engineering and astronaut population and evaluate the vehicle design as the test subjects perform simulations of various operational tasks. However, lunar outpost designs must be evaluated without the use of mockups, creating a need for evaluation tools that can be performed on two-dimension conceptual spacecraft layouts, such as floor plans. A tool based on the Cooper- Harper scale was developed and applied to one lunar scenario, enabling engineers to select between two competing floor plan layouts. Keywords: Constellation, human factors, tools, processes, habitat, outpost, Net Habitable Volume, Cooper-Harper.

Kennedy, Kriss J.↗
NASA NTRS2008

Ares I Integrated Test Approach

This slide presentation reviews the testing approach that NASA is developing for the Ares I launch vehicle. NASA is planning a complete series of development, qualification and verification tests. These include: (1) Upper stage engine sea-level and altitude testing (2) First stage development and qualification motors (3) Upper stage structural and thermal development and qualification test articles (4) Main Propulsion Test Article (MPTA) (5) Upper stage green run testing (6) Integrated Vehicle Ground Vibration Testing (IVGVT) and (7) Aerodynamic characterization testing.

Taylor, Jim↗