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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Assembly Test Article (ATA)

The assembly test article (ATA) consisted of two live loaded redesigned solid rocket motor (RSRM) segments which were assembled and disassembled to simulate the actual flight segment stacking process. The test assembly joint was flight RSRM design, which included the J-joint insulation design and metal capture feature. The ATA test was performed mid-November through 24 December 1987, at Kennedy Space Center (KSC), Florida. The purpose of the test was: certification that vertical RSRM segment mating and separation could be accomplished without any damage; verification and modification of the procedures in the segment stacking/destacking documents; and certification of various GSE to be used for flight assembly and inspection. The RSRM vertical segment assembly/disassembly is possible without any damage to the insulation, metal parts, or seals. The insulation J-joint contact area was very close to the predicted values. Numerous deviations and changes to the planning documents were made to ensure the flight segments are effectively and correctly stacked. Various GSE were also certified for use on flight segments, and are discussed in detail.

Ricks, Glen A.↗
NASA NTRS1973

Compression test assembly

A compression test assembly is described which prevents buckling of small diameter rigid specimens undergoing compression testing and permits attachment of extensometers for strain measurements. The test specimen is automatically aligned and laterally supported when compressive force is applied to the end caps and transmitted to the test specimen during testing.

Kariotis, A. H.↗
NASA NTRS2019

A Simple Transient Thermal Test Assembly for Insulation Materials

A simple transient thermal test was developed for evaluating the thermal performance of high-temperature flexible insulation materials in atmospheric pressure air. The test setup was inspired by the test assembly used for evaluating the performance of fire shelters and fire protective clothing. The heating source used was a burner supplied with propane gas that can generate relatively uniform heating over a wide area. The ratio of the in-plane width to thickness of the insulation test sample in the test assembly was selected to be greater than ten so that the heat transfer in the center of the test assembly was nearly one-dimensional. A rigid, thin Inconel plate was used as the septum plate directly exposed to the flame to provide a relatively uniform, known-temperature boundary condition for the test assembly, and to prevent convective heat transfer through the test insulation from the burner. The test sample, flexible alumina paper insulation, was placed between the Inconel plate and a thin titanium witness plate. The overall assembly was further insulated using a combination of rigid and flexible ceramic insulations to minimize heat losses from the periphery of the test assembly. Thermocouples installed on the septum and witness plates and inside the insulation test sample provided temperature measurements at various locations. For the evaluation tests, the Inconel septum plate reached temperatures between 780°C and 850°C for tests with flame exposure durations of 120 sec to 300 sec. The measured temperatures for various tests with similar flame exposure times were repeatable. A one-dimensional numerical heat transfer model of the test assembly was developed. The close agreement between measured and predicted temperatures on the titanium witness plate and inside the insulation test sample indicated that this test may provide a one-dimensional thermal testing capability for evaluation of thermal performance of similar insulations.

Daryabeigi, Kamran↗
NASA NTRS2007

Development of a Cryogenic Thermal Distortion Measurement Facility for Testing the James Webb Space Telescope Instrument Support Integration Module 2-D Test Assemblies

The James Webb Space Telescope Instrument Support Integration Module (ISIM) is being designed and developed at the Goddard Space Flight Center. The ISM Thermal Distortion Testing (ITDT) program was started with the primary objective to validate the ISM mechanical design process. The ITDT effort seeks to establish confidence and demonstrate the ability to predict thermal distortion in composite structures at cryogenic temperatures using solid element models. This-program's goal is to better ensure that ISIM meets all the mechanical and structural requirements by using test results to verify or improve structural modeling techniques. The first step to accomplish the ITDT objectives was to design, and then construct solid element models of a series 2-D test assemblies that represent critical building blocks of the ISIM structure. Second, the actual test assemblies consisting of composite tubes and invar end fittings were fabricated and tested for thermal distortion. This paper presents the development of the GSFC Cryo Distortion Measurement Facility (CDMF) to meet the requirements of the ISIM 2-D test. assemblies, and other future ISIM testing needs. The CDMF provides efficient cooling with both a single, and two-stage cryo-cooler. Temperature uniformity of the test assemblies during thermal transients and at steady state is accomplished by using sapphire windows for all of the optical ports on the radiation shields and by using .thermal straps to cool the test assemblies. Numerical thermal models of the test assemblies were used to predict the temperature uniformity of the parts during cooldown and at steady state. Results of these models are compared to actual temperature data from the tests. Temperature sensors with a 0.25K precision were used to insure that test assembly gradients did not exceed 2K lateral, and 4K axially. The thermal distortions of two assemblies were measured during six thermal cycles from 320K to 35K using laser interferometers. The standard deviation for all of the distortion measurements is less than 0.5 microns, which falls within the ISIM requirement of 3 microns.

Miller, Franklin↗
NASA NTRS1974

Anti-buckling fatigue test assembly

An antibuckling fatigue test assembly is described for holding a metal specimen which is subjected to compression and to rapid cyclical heating and cooling while permitting visual observation. In an illustrative embodiment of this invention, the anti-buckling fatigue test apparatus includes first and second guide members between which the metal specimen is disposed and held, a heating assembly comprising a suitable heating source such as a quartz lamp and a reflecting assembly directing the heat onto the specimen, and a cooling assembly for directing a suitable cooling fluid such as air onto the specimen. The guide members each have a passage to permit the heat to be directed onto the specimen. An opening is provided in the reflecting assembly to permit visual inspection of that region of the specimen adjacent to the opening onto which the heat is directed.

Eichenbrenner, F. F.↗
NASA NTRS2020

Prokaryotic and Fungal Characterization of the Facilities Used to Assemble, Test, and Launch the OSIRIS-REx Spacecraft

To characterize the ATLO (Assembly, Test, and Launch Operations) environment of the OSIRIS-REx spacecraft, we analyzed 17 aluminum witness foils and two blanks for bacterial, archaeal, fungal, and arthropod DNA. Under NASA’s Planetary Protection guidelines, OSIRIS-REx is a Category II outbound, Category V unrestricted sample return mission. As a result, it has no bioburden restrictions. However, the mission does have strict organic contamination requirements to achieve its primary objective of returning pristine carbonaceous asteroid regolith to Earth. Its target, near-Earth asteroid (101955) Bennu, is likely to contain organic compounds that are biologically available. Therefore, it is useful to understand what organisms were present during ATLO as part of the larger contamination knowledge effort—even though it is unlikely that any of the organisms will survive the multi-year deep space journey. Even though these samples of opportunity were not collected or preserved for DNA analysis, we successfully amplified bacterial and archaeal DNA (16S rRNA gene) from 16 of the 17 witness foils containing as few as 7 ± 3 cells per sample. Fungal DNA (ITS1) was detected in 12 of the 17 witness foils. Despite observing arthropods in some of the ATLO facilities, arthropod DNA (COI gene) was not detected. We observed 1,009 bacterial and archaeal sOTUs (sub-operational taxonomic units, 100% unique) and 167 fungal sOTUs across all of our samples (25–84 sOTUs per sample). The most abundant bacterial sOTU belonged to the genus Bacillus. This sOTU was present in blanks and may represent contamination during sample handling or storage. The sample collected from inside the fairing just prior to launch contained several unique bacterial and fungal sOTUs that describe previously uncharacterized potential for contamination during the final phase of ATLO. Additionally, fungal richness (number of sOTUs) negatively correlates with the number of carbon-bearing particles detected on samples. The total number of fungal sequences positively correlates with total amino acid concentration. These results demonstrate that it is possible to use samples of opportunity to characterize the microbiology of low-biomass environments while also revealing the limitations imposed by sample collection and preservation methods not specifically designed with biology in mind.

Aaron B. Regberg↗
NASA NTRS1995

Flexseal Insulator Test Assembly

Small-scale version of solid-fuel rocket motor flexseal nozzle bearing assembly instrumented and tested in compression-testing fixture simulating conditions during rocket motor operation described in report.

Buchanan, Eric↗
NASA NTRSDate not supplied

Defining Pupil Knowledge Requirements for Roman Space Telescope Integrated Payload Assembly Testing

This thesis examines the use of phase retrieval to characterize an optical system under testing conditions with pupil knowledge error. The purpose of this investigation is to define pupil knowledge requirements for the integrated payload testing of the Roman Space Telescope. We have conducted a Monte Carlo study to determine how location uncertainty of the ground support equipment relative to the payload caused by the temperature deformation in the Space Environment Simulator will affect our ability to use image-based wavefront sensing during the test to characterize system alignment. This test will be conducted with significant wavefront error (WFE) present due to gravity sag on the primary mirror. The study incrementally decenters two pieces of ground support equipment and evaluates how the phase retrieval algorithm attempts to fit the wavefront. We conducted this investigation in two steps. First, we used an ideal optical model of the test configuration without the gravity sag on the primary mirror to see the fitting effects related only to pupil knowledge error introduced by the decentering. Then, we used perturbed and gravity sag models to investigate the effects of decentering dependent wavefront effects in addition to pupil knowledge error. The results from the ideal model provided a clear limit of the amount of pupil knowledge error that can be present before seeing significant WFE in the phase retrieval. For the second study, we used the decentering tolerances from the ideal model results to determine the WFE effects of decentering in the presence of gravity sag and system misalignments. The second part of this study will be factored into the overall integrated payload assembly testing WFE budget.

Roman Space Telescope↗
NASA NTRS1985

Test chip assembler and test program generator

One of the major problems in working at the geometry level for the generation of either test structure or functional circuit designs is the amount of labor involved in the design phase. To reduce the amount of labor involved in both the design and test of the structures used, JPL has developed a design and test program consisting of a Test Chip Assembler (TCA) and a Test Program Generator (TPG), which creates the geometrical description of the structures and generates the necessary test information using a high-level language. This system reduces the design time for a test chip by a factor of 30. To analyze the data obtained from wafer probing, a statistical package called STMJPL was developed. Some of the capabilities of the JPL software (STMJPL) are described.

Pina, C. A.↗
NASA NTRS2022

Defining Pupil Knowledge Requirements for Roman Space Telescope Integrated Payload Assembly Testing

This thesis examines the use of phase retrieval to characterize an optical system under testing conditions with pupil knowledge error. The purpose of this research is to define pupil knowledge requirements for the integrated payload testing of the Roman Space Telescope (RST). I have conducted a Monte Carlo study to determine how uncertainty in the location of the ground support equipment relative to the payload will affect the ability to use image-based wavefront sensing during the test to characterize system alignment. This test will be conducted in the Space Environment Simulator (SES) with the presence of Wavefront Error (WFE) due to gravity sag on the primary mirror. In this study, I incrementally decentered a piece of ground support equipment, the SubAperture Metrology System (SAMS), and evaluated how the phase retrieval algorithm attempted to fit the wavefront with the pupil mismatch. The results of this study are a factor in the overall Integrated Payload Assembly (IPA) testing WFE budget.

Roman Space Telescope↗
NASA NTRS2023

The Assembly, Test, and Integration of LOFTID (Low-Earth Orbit Flight Test of an Inflatable Decelera-tor)

R.J. Bodkin Biography Mr. Bodkin worked in industry for a rapid prototype company focusing on UAVs and manned experimental aircraft. Later he served as the Inflation System Lead on IRVE-II and 3 and the Re-Entry Vehicle Lead for LOFTID at NASA Langley Research Center. Introduction: The Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID), developed in partnership with United Launch Alliance (ULA) and flown in conjunction with the National Oceanic and Atmospheric Administration (NOAA) Joint Polar Satellite System-2 (JPSS-2) satellite, demonstrated Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology has progressed and is ready for mission infusion. LOFTID’s success demonstrates that aeroshells are not limited to the internal diame-ter of the launch vehicle payload fairing, allowing larger payloads to be deployed to the surfaces of planetary bodies with atmospheres. The challenges of assembling, integrating, and testing this revolutionary spacecraft will be dis-cussed as well as issues associated with doing this with a fixed launch date the project did not control. Assembly: Because LOFTID flew as a rideshare partner with JPSS-2, it was constrained with addi-tional schedule, milestone, and technical require-ments that were beyond the project’s control. As-sembly of the LOFTID hardware was challenged with the normal mechanical fit issues while also having to navigate the SARS-COVID-II pandemic. Challenges ranged from availability of team per-sonnel required on-site for vehicle assembly to dif-ficulties associated with team collaboration while working remotely and increased costs and lead times of components due to supply chain con-straints. Numerous additional challenges cascaded from the additional time required. Integration: LOFTID flew as a secondary pay-load to JPSS-2 in a mission-unique configuration, directly under JPSS-2 primary payload, inside the Payload Adapter that integrated JPSS-2 to the Atlas V launch vehicle. A mission unique Payload Adapt-er Separation System (PASS) was required to sepa-rate the Payload Adapter from the Launch Vehicle prior to the start of the LOFTID flight demonstra-tion. Development of this system was challenging due to a shortened development schedule resulting from the iterative nature of Payload Adapter devel-opment with the partners at ULA. Preparations to integrate the main segments of the LOFTID vehicle posed unique challenges of having to accommodate issues with a fixed launch date that led to some cre-ative solutions to the integration. The partnership agreement with ULA and JPSS-2 resulted in a mass simulator designed to be installed late in the inte-gration in the event the LOFTID vehicle was not ready in time.. Test: LOFTID testing was carried out in several phases. Some components were tested at the com-ponent level, others at the sub-system levels and then finally the integrated vehicle level. This culmi-nated with the Complete Systems Test (CST) per-formed in a vacuum chamber as one of the final checkouts prior to disassembly for re-packing of the aeroshell. CST challenges will be discussed as well as obstacles encountered post-CST. After CST, the vehicle was disassembled so the HIAD could be repacked, and the vehicle was reassembled for ac-ceptance vibration testing. Testing concluded with the fully assembled vehicle being shipped to the launch site for final testing and integrations with the Payload Adapter to JPSS-2 for launch and opera-tions. Conclusion: The challenges posed by the AI&T for LOFTID could inform the planetary community of some of the opportunities and challenges of de-veloping technologies on a rideshare with a rela-tively small budget.

R.J. Bodkin↗
NASA NTRS2000

International Space Station Carbon Dioxide Removal Assembly Testing

Performance testing of the International Space Station Carbon Dioxide Removal Assembly flight hardware in the United States Laboratory during 1999 is described. The CDRA exceeded carbon dioxide performance specifications and operated flawlessly. Data from this test is presented.

Knox, James C.↗
NASA NTRS1988

Results of EVA/mobile transporter space station truss assembly tests

Underwater neutral buoyance tests were conducted to evaluate the use of a Mobile Transporter concept in conjunction with EVA astronauts to construct the Space Station Freedom truss structure. A three-bay orthogonal tetrahedral truss configuration with a 15 foot square cross section was repeatedly assembled by a single pair of pressure suited test subjects working from the Mobile Transporter astronaut positioning devices (mobile foot restraints). The average unit assembly time (which included integrated installation of utility trays) was 27.6 s/strut, or 6 min/bay. The results of these tests indicate that EVA assembly of space station size structures can be significantly enhanced when using a Mobile Transporter equipped with astronaut positioning devices. Rapid assembly time can be expected and are dependent primarily on the rate of translation permissible for on-orbit operations. The concept used to demonstate integrated installation of utility trays requires minimal EVA handling and consequentially, as the results show, has little impact on overall assembly time.

Watson, Judith J.↗
NASA NTRS1990

RS-88 Pad Abort Demonstrator Thrust Chamber Assembly Testing at NASA Marshall Space Flight Center

This paper documents the effort conducted to collect hot-tire dynamic and acoustics environments data during 50,000-lb thrust lox-ethanol hot-fire rocket testing at NASA Marshall Space Flight Center (MSFC) in November-December 2003. This test program was conducted during development testing of the Boeing Rocketdyne RS-88 development engine thrust chamber assembly (TCA) in support of the Orbital Space Plane (OSP) Crew Escape System Propulsion (CESP) Program Pad Abort Demonstrator (PAD). In addition to numerous internal TCA and nozzle measurements, induced acoustics environments data were also collected. Provided here is an overview of test parameters, a discussion of the measurements, test facility systems and test operations, and a quality assessment of the data collected during this test program.

Farr, Rebecca A.↗
NASA NTRS1979

Simulated EVA operation of a remote connector assembly test report

The features of a connector concept with respect to timelines and ease of connection by EVA (extravehicular activity), in various mating orientations were evaluated. The connector tests were conducted by thee EVA astronaut test subjects. Each of four test conditions (baseline, off angle, overhead, and with visual obstruction) were run three times by each of the test subjects. Time data were taken on each test run. Visual and voice communications with the subjects were recorded. The tests demonstrated that EVA personnel can perform connection tasks in relatively short times (generally one minute) and the connector configuration was a reasonable design base for such tasks. The in-situ communications and post-test comments indicated that the connector was generally acceptable but requires improvement to its manual interface features.

Lefever, A.↗