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All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

BRAINSTACK – A Platform for Artificial Intelligence & Machine Learning Collaborative Experiments on a Nano-Satellite

As space missions continue to become more ambitious, complex, and distant to Earth, the need for advanced on-board intelligent decision making to guide everything from mission operations to fault detection and recovery has become a major front of space research. While the prevalence of research on such Artificial Intelligence / Machine Learning (AI/ML) modules has exploded, the capacity to experimentally validate such modules in space in a rapid and inexpensive format has not. To this end, the Nano Orbital Workshop (NOW) group at NASA Ames Research Center has been at the forefront of performing initial flight evaluation tests of ‘commercially’ available AI/ML computational platforms via the TechEdSat (TES-n) flight series as part of what is programmatically referred to as the BRAINSTACK. BRAINSTACK will provide an orbital AI/ML evaluation laboratory where computational experiments are pre-loaded into memory prior to launch, and then executed as desired during the mission, with results reported back and program tweaks or new data sets uploaded as needed. Processors selected as part of the BRAINSTACK are of ideal size, packaging, and power consumption for easy integration into a cube satellite structure. These experiments have included the evaluation of small, high-performance GPUs and more recently, neuromorphic processors in LEO operations. Neuromorphic processors are of particular interest due to their superior computational power efficiency over GPUs. The first TES-n flight test of an Intel first-generation Loihi neuromorphic processor launched on January 13, 2022 and continues to operate in orbit despite almost no space environment modifications. The Intel Loihi Gen-1 is characterized by a 14nm 128-core Spiking Neural Network (SNN) able to support on-chip training. This experiment utilized a Loihi packaged in the ‘Kapoho Bay’ USB module, providing a relatively straight-forward interface to the bus avionics system. The Kapoho Bay was in turn managed by a host Intel Pentium single-board computer to handle scheduling of the AI/ML application payloads, and communications with the satellite vehicle manager. The recently released Intel Loihi Gen-2, able to support integer-valued spike payloads and produced using 7nm process, will form part of the basis of the evolving BRAINSTACK in the upcoming three TES-n/NOW flights. Additionally, it is planned to measure the radiation environment these processors experience to understand any degradation or computational artifacts caused by long term space radiation exposure on these novel architectures. This evolving flexible and collaborative environment involving various research teams across NASA and other organizations is intended to be a convenient orbital test platform from which many anticipated future space AI/ML applications may be initially tested.

Artificial Intelligence↗
NASA NTRSDate not supplied

BRAINSTACK – A Platform for Artificial Intelligence & Machine Learning Collaborative Experiments on a Nano-Satellite

As space missions continue to become more ambitious, complex, and distant to Earth, the need for advanced on-board intelligent decision making to guide everything from mission operations to fault detection and recovery has become a major front of space research. While the prevalence of research on such Artificial Intelligence / Machine Learning (AI/ML) modules has exploded, the capacity to experimentally validate such modules in space in a rapid and inexpensive format has not. To this end, the Nano Orbital Workshop (NOW) group at NASA Ames Research Center has been at the forefront of performing initial flight evaluation tests of ‘commercially’ available AI/ML computational platforms via the TechEdSat (TES-n) flight series as part of what is programmatically referred to as the BRAINSTACK. BRAINSTACK will provide an orbital AI/ML evaluation laboratory where computational experiments are pre-loaded into memory prior to launch, and then executed as desired during the mission, with results reported back and program tweaks or new data sets uploaded as needed. Processors selected as part of the BRAINSTACK are of ideal size, packaging, and power consumption for easy integration into a cube satellite structure. These experiments have included the evaluation of small, high-performance GPUs and more recently, neuromorphic processors in LEO operations. Neuromorphic processors are of particular interest due to their superior computational power efficiency over GPUs. The first TES-n flight test of an Intel first-generation Loihi neuromorphic processor launched on January 13, 2022 and continues to operate in orbit despite almost no space environment modifications. The Intel Loihi Gen-1 is characterized by a 14nm 128-core Spiking Neural Network (SNN) able to support on-chip training. This experiment utilized a Loihi packaged in the ‘Kapoho Bay’ USB module, providing a relatively straight-forward interface to the bus avionics system. The Kapoho Bay was in turn managed by a host Intel Pentium single-board computer to handle scheduling of the AI/ML application payloads, and communications with the satellite vehicle manager. The recently released Intel Loihi Gen-2, able to support integer-valued spike payloads and produced using 7nm process, will form part of the basis of the evolving BRAINSTACK in the upcoming three TES-n/NOW flights. Additionally, it is planned to measure the radiation environment these processors experience to understand any degradation or computational artifacts caused by long term space radiation exposure on these novel architectures. This evolving flexible and collaborative environment involving various research teams across NASA and other organizations is intended to be a convenient orbital test platform from which many anticipated future space AI/ML applications may be initially tested.

Artificial Intelligence↗
NASA NTRS2011

Materials and Nondestructive Evaluation Laboratoriers: User Test Planning Guide

The Materials and Nondestructive Evaluation Laboratory process, milestones and inputs are unknowns to first-time users. The Materials and Nondestructive Evaluation Laboratory Planning Guide aids in establishing expectations for both NASA and non- NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware developers. It is intended to assist their project engineering personnel in materials analysis planning and execution. Material covered includes a roadmap of the analysis process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, products, and inputs necessary to define scope of analysis, cost, and schedule are included as an appendix to the guide.

Schaschl, Leslie↗
DOE OSTI2018

Repeatable and reproducible measurements of myocardial oxidative metabolism, blood flow and external efficiency using {sup 11}C-acetate PET

Background: Non-invasive approaches to investigate myocardial efficiency can help track the progression of heart failure (HF). This study evaluates the repeatability and reproducibility of {sup 11}C-acetate positron emission tomography (PET) imaging of oxidative metabolism. Methods and results: Dynamic {sup 11}C-acetate PET scans were performed at baseline and followup (47 ± 22 days apart) in 20 patients with stable HF with reduced ejection fraction. Two observers blinded to patients’ clinical data used FlowQuant{sup ®} to evaluate test–retest repeatability, as well as intra- and inter-observer reproducibility of {sup 11}C-acetate tracer uptake and clearance rates, for the measurement of myocardial oxygen consumption (MVO{sub 2}), myocardial external efficiency (MEE), work metabolic index (WMI), and myocardial blood flow. Reproducibility and repeatability were evaluated using intra-class-correlation (ICC) and Bland–Altman coefficient-of-repeatability (CR). Test–retest correlations and repeatability were better for MEE and WMI compared to MVO{sub 2}. All intra- and inter-observer correlations were excellent (ICC = 0.95-0.99) and the reproducibility values (CR = 3%-6%) were significantly lower than the test–retest repeatability values (22%-54%, P < 0.001). Repeatability was improved for all parameters using a newer PET–computed tomography (CT) scanner compared to older PET-only instrumentation. Conclusion: {sup 11}C-acetate PET measurements of WMI and MEE exhibited excellent test–retest repeatability and operator reproducibility. Newer PET–CT scanners may be preferred for longitudinal tracking of cardiac efficiency. [French] French Abstract: Contexte: Les examens non invasifs de la fonction myocardique aident à suivre la progression de l’insuffisance cardiaque. Dans ce travail, nous avons évalué la répétabilité et la reproductibilité de l’étude du métabolisme oxydatif du myocarde par imagerie tomographique à positrons avec l’acétate marqué au carbone 11. Méthodes et résultats: Une étude de base et un second examen TEP dynamique à l’ acétate marqué au carbone 11 ont été réalisés (47 ± 22 jours) chez 20 patients présentant une insuffisance cardiaque stable avec une fraction d’éjection réduite. Sans aucune connaissance des données cliniques et au moyen du programme FlowQuant®, deux observateurs ont évalué la répétabilité des TEPs de base et de leur suivi, la reproductibilité intra- et inter-observateur, l’absorption et la clearance du traceur, la mesure de la consommation d’oxygène du myocarde (MVO2), l’efficacité contractile du myocarde (MEE), l’index métabolique du travail myocardique (WMI) et le débit sanguin myocardique (MBF). La reproductibilité et la répétabilité ont été évaluées en utilisant la corrélation intra-classe (ICC) et le coefficient de répétabilité Altman (CR). Les corrélations entre les études de base et leur suivi et la répétabilité des données se sont avérées supérieures pour les paramètres MEE et WMI par rapport à MVO2. Toutes les corrélations intra- et inter-observateurs furent excellentes (ICC = 0,95-0,99). Les valeurs de reproductibilité (CR = 3-6%) furent significativement inférieures aux valeurs de répétabilité (22-54%, p <0.001). La répétabilité des paramètres mesurés s’est avérée supérieure avec un scanner TEP-TDM de nouvelle génération par rapport à l’utilisation de la TEP sans TDM Conclusion: Les mesures réalisées dans cette étude TEP 11C-acétate montre une excellent répétabilité et reproductibilité des paramètres WMI et WMI entre les examens de base et leur suivi effectués par des opérateurs différents. Les nouveaux scanners TEP-TDM devraient être préférés pour le suivi longitudinal de la fonction cardiaque. [Spanish] Spanish Abstract: Antecedentes: el abordaje no invasivo para investigar la eficiencia miocárdica puede ayudar en el seguimiento de la progresión de la insuficiencia cardíaca. Este estudio evalúa la repetibilidad y la reproducibilidad del estudio de metabolismo oxidativo con PET 11C-acetato. Métodos y resultados: Se realizaron estudios de PET 11C-acetato dinámicos al inicio y durante el seguimiento (47 ± 22 días de diferencia) en 20 pacientes con insuficiencia cardíaca estable y fracción de eyección reducida. Dos observadores cegados a los datos clínicos de los pacientes utilizaron FlowQuant® para evaluar la repetibilidad de la prueba-reprueba, así como la reproducibilidad intra e interobservador de la captación de radiotrazador 11C-acetato y sus tasas de eliminación, la medición del consumo miocárdico de oxígeno (MVO2), la eficiencia externa miocardica (EEM), el índice trabajo-metabólico (ITM) y flujo sanguíneo miocárdico (FSM). La reproducibilidad y la repetibilidad se evaluaron mediante la correlación intraclase (ICC) y el coeficiente de repetibilidad (CR) de Bland-Altman. Las correlaciones Prueba-Reprueba y la repetibilidad fueron mejores para la EEM y el ITM en comparación con el MVO2. Todas las correlaciones intra e interobservador fueron excelentes (ICC = 0.95-0.99) y los valores de reproducibilidad (CR = 3-6%) fueron significativamente menores que los valores de repetibilidad prueba-reprueba (22-54%, p <0.001). La repetibilidad fue mejor para todos los parámetros utilizando un equipo PET-TC más nuevo en comparación con un equipo PET sin CT. Conclusión: las mediciones del PET con 11C-acetato del ITM y EEM mostraron una excelente repetibilidad prueba-preprueba y reproducibilidad del operador. Los nuevos equipos PET-CT pueden ser elegidos para el seguimiento longitudinal de la eficiencia miocárdica. [Chinese] Chinese Abstract: 背景: 采用非侵入式方法来研究心肌代谢效率可以帮助追踪心力衰竭的过程。本研究评估利用碳-11 醋酸盐为 PET 显影剂行氧化代谢成像的可重复性和可再现性。 方法和结果: 纳入射血分数减低的 20 名稳定性心衰患者,对患者基线和 47±22 天随访都进行碳-11 醋酸盐 PET 扫描。为测量心肌耗氧量(MVO{sub 2}), 心肌外效率(MEE), 工作代谢指标(WMI)和心肌血流量(MBF), 两名观察者按照双盲的方法利用 FlowQuant®对碳-11 醋酸盐的摄取率和清空率进行了重复性测试以及不同观察者之间的可再现性测试。采用组内相关系数(ICC)和 Bland Altman 可重复性系数(CR)分别对可再现性和可重复性进行评估。MEE 和 WMI 的两次试验系数和可重复性优于MVO{sub 2}。所有观察者之间的相关系数都较好(ICC=0.95-0.99),可再现性系数的值(CR=3-6%)明显低于两次试验可重复性的值(22-54%, P<0.001)。相比于旧的只有 PET 的设备, 采用新型 PET-CT 扫描仪能够使所有参数的可再现性都有所提高。 结论: 碳-11醋酸盐 PET 显像测量 WMI 和 MEE 有很好的可重复性和可再现性。新的 PET-CT 扫描仪可能更适合于心脏代谢效率的长期追踪。.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
NASA NTRS1974

Design guidelines for use of adhesives and organic coatings in hybrid microcircuits

A study was conducted to investigate the reliability of organic adhesives in hybrid microcircuits. The objectives were twofold: (1) to identify and investigate problem areas that could result from the use of organic adhesives and (2) to develop evaluation tests to quantify the extent to which these problems occur for commercially available adhesives. Efforts were focused on electrically conductive adhesives. Also, a study was made to evaluate selected organic coatings for contamination protection for hybrid microcircuits.

Caruso, S. V.↗
NASA NTRS1979

Feasibility of SiC composite structures for 1644 deg gas turbine seal applications

The feasibility of silicon carbide composite structures was evaluated for 1644 K gas turbine seal applications. The silicon carbide composites evaluated consisted of Si/SiC Silcomp (Trademark) - and sintered silicon carbide as substrates, both with attached surface layers containing BN as an additive. A total of twenty-eight candidates with variations in substrate type and density, and layer chemistry, density, microstructure, and thickness were evaluated for abradability, cold particle erosion resistance, static oxidation resistance, ballistic impact resistance, and fabricability. The BN-free layers with variations in density and pore size were later added for evaluation. The most promising candidates were evaluated for Mach 1.0 gas oxidation/erosion resistance from 1477 K to 1644 K. The as-fabricated rub layers did not perform satisfactorily in the gas oxidation/erosion tests. However, preoxidation was found to be beneficial in improving the hot gas erosion resistance. Overall, the laboratory and rig test evaluations show that material properties are suitable for 1477 K gas turbine seal applications.

Darolia, R.↗
NASA NTRS1980

Method of mitigating titanium impurities effects in p-type silicon material for solar cells

Microstructural evaluation tests performed on Cu-doped, Ti-doped and Cu/Ti doped p-type silicon single crystal wafers, before and after the solar cell fabrication, and evaluation of both dark forward and reverse I-V characteristic records for the solar cells produced from the corresponding silicon wafers, show that Cu mitigates the unfavorable effects of Ti, and thus provides for higher conversion efficiency, thereby providing an economical way to reduce the deleterious effects of titanium, one of the impurities present in metallurgical grade silicon material.

Salama, A. M.↗
NASA NTRS1986

Stability, reliability and cross-mode correlations of tests in a recommended 8-minute performance assessment battery

A need exists for an automated performance test system to study drugs, agents, treatments, and stresses of interest to the aviation, space, and environmental medical community. The purpose of this present study is to evaluate tests for inclusion in the NASA-sponsored Automated Performance Test System (APTS). Twenty-one subjects were tested over 10 replications with tests previously identified as good candidates for repeated-measure research. The tests were concurrently administered in paper-and-pencil and microcomputer modes. Performance scores for the two modes were compared. Data from trials 1 to 10 were examined for indications of test stability and reliability. Nine of the ten APT system tests achieved stability. Reliabilities were generally high. Cross-correlation of microbased tests with traditional paper-and-pencil versions revealed similarity of content within tests in the different modes, and implied at least three cognition and two motor factors. This protable, inexpensive, rugged, computerized battery of tests is recommended for use in repeated-measures studies of environmental and drug effects on performance. Identification of other tests compatible with microcomputer testing and potentially capable of tapping previously unidentified factors is recommended. Documentation of APTS sensitivity to environmental agents is available for more than a dozen facilities and is reported briefly. Continuation of such validation remains critical in establishing the efficacy of APTS tests.

Wilkes, R. L.↗
NASA NTRS2023

BRAINSTACK – A Platform for Artificial Intelligence & Machine Learning Collaborative Experiments on a Nano-Satellite

As the space economy continues to expand through increasingly easy access to advanced and inexpensive technology, space missions themselves have become more ambitious with exploration targets growing ever distant while simultaneously requiring larger guidance and communication budgets. These conflicting desires of distance and control drive the need for advanced on-board intelligent decision making to reduce communication and control limitations by automating as many mission functions as possible in-situ. While the amount of research on such Artificial Intelligence and Machine Learning (AI/ML) software modules has grown exponentially, the capacity to experimentally validate such software modules in space in a rapid and inexpensive format has not. To this end, the Nano Orbital Workshop (NOW) group at NASA Ames Research Center has been at the forefront of performing initial flight evaluation tests of ‘commercially’ available bleeding-edge computational platforms via what is programmatically referred to as the BrainStack on the TechEdSat (TES-n) flight series. This on-orbit computational platform provides an evaluation laboratory where advanced software experiments are pre-loaded into memory prior to launch, then executed as payloads during mission operations with results reported back and program tweaks or new training sets uploaded as needed. Processors selected as part of the BrainStack are of ideal size, packaging, and power consumption for easy integration into a cube satellite structure. These experiments have included the evaluation of small, high-performance GPUs and, more recently, neuromorphic processors, in LEO operations. Neuromorphic processors are of particular interest due to their superior power efficiency over GPUs in intelligent automation applications. The first TES-n flight test of an Intel first-generation Loihi neuromorphic processor launched on TES-13, January 13, 2022, and continues to operate in orbit despite no significant modifications to harden the processor against the space environment. The Intel Loihi Gen-1 on TES-13 is characterized by a 14nm 128-core Spiking Neural Network (SNN) able to support on-chip training. The processor is packaged in the Kapoho Bay USB module, providing a relatively straight-forward interface to the bus avionics system. The Kapoho Bay was in turn managed by an Intel Pentium single-board computer to handle scheduling of the software application payloads and communications with the satellite’s primary computer. The recently released Intel Loihi Gen-2, able to support integer-valued spike payloads and produced using 7nm process, will form part of the continually evolving BrainStack in the upcoming three TES-n/NOW flights. The Kapoho Point unit will incorporate eight Loihi-2 processors, enabling neural networks of up to one million neurons and one billion synapsis. Additionally, it is planned to measure the radiation environment these processors experience to understand any degradation or computational artifacts caused by long term space radiation exposure on these novel architectures. This evolving flexible and collaborative environment involving various research teams across NASA and other organizations is intended to be a convenient orbital test platform from which many anticipated future space automation applications may be initially tested.

Artificial Intelligence↗
NASA NTRS2007

Test Methodology to Evaluate the Safety of Materials Using Spark Incendivity

For many years scientists and engineers have been searching for the proper test method to evaluate an electrostatic risk for materials used in hazardous environments. A new test standard created by the International Electrotechnical Commission is a promising addition to conventional test methods used throughout industry. The purpose of this paper is to incorporate this test into a proposed new methodology for the evaluation of materials exposed to flammable environments. However, initial testing using this new standard has uncovered some unconventional behavior in materials that conventional test methods were thought to have reconciled. For example some materials tested at higher humidities were more susceptible to incendive discharges than at lower humidity even though the surface resistivity was lower.

Buhler, Charles↗
NASA NTRS1976

Development of a Self-contained Heat Rejection Module (SHRM), phase 1

The laboratory prototype test hardware and testing of the Self-Contained Heat Rejection Module are discussed. The purpose of the test was to provide operational and design experience for application to a flight prototype design. It also provided test evaluation of several of the actual components which were to be used in the flight prototype hardware. Several changes were made in the flight prototype design due to these tests including simpler line routing, relocation of remote operated valves to a position upstream of the expansion valves, and shock mounting of the compressor. The concept of heat rejection control by compressor speed reduction was verified and the liquid receiver, accumulator, remote control valves, oil separator and power source were demonstrated as acceptable. A procedure for mode changes between pumped fluid and vapor compression was developed.

Fleming, M. L.↗
NASA NTRS1979

Indoor test for thermal performance evaluation of seven Elcam fin-tube solar collector configurations

The test procedure used and the results obtained from an evaluation test program conducted to obtain thermal performance data on seven Elcam fin-tube solar collector configurations under simulated conditions are described. These tests were made using the Marshall Space Flight Center solar facilities. The Elcam fin-tube (liquid) solar collectors each consist of an absorber plate 5.9 inches wide by 83 inches long and a type M copper tube of 0.569 inch nominal inside diameter. No cover plate was used with any of the specimens. The uniqueness of each of the seven configurations is described, and tests were performed on each separate configuration.

Source record↗
DOE OSTI2014

Wind Turbine/Radar Interference: Offshore Test Options

This paper attempts to describe the options to expand the scope of the current Interagency Field Test & Evaluation (IFT&E) objectives to include wind turbine encroachment on agency missions for offshore wind development in the United States. The options described here build on the recently completed IFT&E test campaigns that took place in 2012 and 2013. Those tests, which looked at the CARSR, ASR-11, ARSR-4, and eight proposed mitigation technologies, found that wind turbines can significantly impact the ability of radars to detect aircraft and meet mission requirements above and near wind farms. One of the more immediate successes of the IF&E Program is that today, several of the infill radar technologies which were tested, took the results of their IF&TE performance to move well beyond Technology Readiness Level 6/7 and some have been deployed and are operating at airports in the United Kingdom (UK). As well, the UK Ministry of Defense (MOD) has deployed the replacement radar which was tested to address specific concerns with especially concerning offshore wind farms. The UK MOD continues to test and hopes to refine these systems so that identified shortfalls in surveillance capability and operations which remain can be addressed. Wind energy has been steadily growing in the U.S. With a current capacity of over 60 GW today and the expectation that this capacity will need to grow to 300 GW to meet the U.S. Department of Energy's (DOE) goal of 20% wind energy in the future, offshore wind farms are gaining more attention. The specific impacts of wind turbine interference on maritime radars have not been determined at this time. However, the DOE did fund a study conducted by the University of Texas at Austin entitled, "Assessment of Offshore Wind Farm Effects on Sea Surface, Subsurface and Airborne Electronic Systems," that focused on identifying the broader Wind-Turbine/Radar Interference: Offshore Test Options SAND2014-17870 effects of electromagnetic interference expected to be caused by offshore wind farms.' A review of that study would be worth the reader's time. And while no comprehensive field studies have been accomplished, it is worth noting that many mitigation solutions that were tested I the IFT&E Program are derived from short-range maritime radar systems. The Wind and Water Power Technologies Office (WWPTO), within the DOE Office of Energy Efficiency and Renewable Energy, supports the development, deployment, and commercialization of wind and water power technologies. This report is funded by the WWPTO.

17 WIND ENERGY↗
NASA NTRS1994

Advanced nickel-hydrogen spacecraft battery development

Eagle-Picher currently has several advanced nickel-hydrogen (NiH2) cell component and battery designs under development including common pressure vessel (CPV), single pressure vessel (SPV), and dependent pressure vessel (DPV) designs. A CPV NiH2 battery, utilizing low-cost 64 mm (2.5 in.) cell diameter technology, has been designed and built for multiple smallsat programs, including the TUBSAT B spacecraft which is currently scheduled (24 Nov. 93) for launch aboard a Russian Proton rocket. An advanced 90 mm (3.5 in.) NiH2 cell design is currently being manufactured for the Space Station Freedom program. Prototype 254 mm (10 in.) diameter SPV batteries are currently under construction and initial boilerplate testing has shown excellent results. NiH2 cycle life testing is being continued at Eagle-Picher and IPV cells have currently completed more than 89,000 accelerated LEO cycles at 15% DOD, 49,000 real-time LEO cycles at 30 percent DOD, 37,800 cycles under a real-time LEO profile, 30 eclipse seasons in accelerated GEO, and 6 eclipse seasons in real-time GEO testing at 75 percent DOD maximum. Nickel-metal hydride battery development is continuing for both aerospace and electric vehicle applications. Eagle-Picher has also developed an extensive range of battery evaluation, test, and analysis (BETA) measurement and control equipment and software, based on Hewlett-Packard computerized data acquisition/control hardware.

Coates, Dwaine K.↗
NASA NTRS2023

Establishing Standardized Test Methods for Evaluating Space Suit Gloves

The Artemis space suit glove environmental protection garment (EPG) will be the first line of protection used to protect the crewmember’s hands from the environments encountered during extravehicular activity (EVA). As the Artemis missions will include more extreme environments, it is necessary to define tests to evaluate if gloves can meet new, challenging requirements. The NASA Engineering and Safety Center (NESC)has funded an effort with the goal to help vendors to produce a space suit glove that is sufficiently durable to meet the needs of the Artemis missions. Three problems were identified in meeting that goal. First, there are no standardized tests defined to evaluate the durability of space suit gloves for the extreme lunar environments. Second, there is insufficient data on glove performance in a lunar environment from which to compare new designs. And third, current ISS glove TMG fabrics are unlikely to be sufficient to meet Lunar requirements. Four tasks were established to answer different aspects of these three problems. Task 1 focused on the characterization of potential glove fabrics using ASTM standardized test methods when possible. When one did not exist, new standardized test procedures were devised. Task 2 focused on developing a procedure for characterizing the thermal performance of a glove assembly. Task 3 focused on devising a standard procedure for characterizing the dust/abrasion resistance of a space suit glove. Task 4 focused on devising a standard procedure for characterizing the cut resistance of a space suit glove while at cryogenic temperatures. The new procedures created in Tasks 2, 3 and 4 were then validated by testing the Phase VI glove to collect baseline data. This paper will summarize the approach used to establish standardized test methods for each task and will expound on the ASTM process to publish the new standards.

spacesuit↗
NASA NTRS2011

Full-Scaled Advanced Systems Testbed: Ensuring Success of Adaptive Control Research Through Project Lifecycle Risk Mitigation

The National Aeronautics and Space Administration's Dryden Flight Research Center completed flight testing of adaptive controls research on the Full-Scale Advance Systems Testbed (FAST) in January of 2011. The research addressed technical challenges involved with reducing risk in an increasingly complex and dynamic national airspace. Specific challenges lie with the development of validated, multidisciplinary, integrated aircraft control design tools and techniques to enable safe flight in the presence of adverse conditions such as structural damage, control surface failures, or aerodynamic upsets. The testbed is an F-18 aircraft serving as a full-scale vehicle to test and validate adaptive flight control research and lends a significant confidence to the development, maturation, and acceptance process of incorporating adaptive control laws into follow-on research and the operational environment. The experimental systems integrated into FAST were designed to allow for flexible yet safe flight test evaluation and validation of modern adaptive control technologies and revolve around two major hardware upgrades: the modification of Production Support Flight Control Computers (PSFCC) and integration of two, fourth-generation Airborne Research Test Systems (ARTS). Post-hardware integration verification and validation provided the foundation for safe flight test of Nonlinear Dynamic Inversion and Model Reference Aircraft Control adaptive control law experiments. To ensure success of flight in terms of cost, schedule, and test results, emphasis on risk management was incorporated into early stages of design and flight test planning and continued through the execution of each flight test mission. Specific consideration was made to incorporate safety features within the hardware and software to alleviate user demands as well as into test processes and training to reduce human factor impacts to safe and successful flight test. This paper describes the research configuration, experiment functionality, overall risk mitigation, flight test approach and results, and lessons learned of adaptive controls research of the Full-Scale Advanced Systems Testbed.

Pavlock, Kate M.↗
NASA NTRSDate not supplied

Stochastic Verification by Analysis for Autonomous Systems Management Architecture (ASMA)

The Gateway Vehicle Systems Manager (VSM) is the top-level of a distributed, hierarchical software control system. VSM is data-driven and will make decisions related to mission, fault, resource management and vehicle control. These attributes combined with a high degree of autonomy make it susceptible to emergent behavior. In order to achieve the high level of confidence needed in this critical system, the VSM team has developed a multifaceted verification strategy employing traditional verification techniques, simulation, model checking, and runtime verification. Individual algorithms are verified using conventional testing and model checking using assume-guarantee contracts. A discrete event-based simulation approach is being developed to verify timelines. This presentation describes an enhancement to the verification approach using analysis to enhance system robustness by detecting and resolving the potential for emergent behavior. The verification by analysis employs a Software in the Loop (SITL) environment with real flight software executing on emulated processors, simulations of vehicle subsystems, flight dynamics, and human inputs. Since the possible input space and configuration data set are too large for exhaustive testing, a Monte Carlo approach is used to cover feasible scenarios, augmented with corner cases and known higher-risk scenarios. A key problem in using Monte Carlo-based system verification is evaluating test results to ensure that system behavior is correct. The presentation describes the approach the VSM team uses to monitor behavior for compliance with predetermined boundaries and to identify anomalous behavior for further analysis. This presentation describes the multi-level systems approach to verification, and the simulation-based layer that covers the feasible state space: 1. Overview of the Gateway VSM 2. Special challenges due to heterogeneous, hierarchical architecture 3. Modeling and simulation environment using flight software and system simulations 4. Developing input sets to ensure state-space coverage 5. Developing model and data configuration sets to ensure model coverage 6. Interpreting results without predetermined outcomes 7. Lessons learned and future work

Verification and Validation↗
NASA NTRS2012

Benchmarking Evaluation Results for Prototype Extravehicular Activity Gloves

The Space Suit Assembly (SSA) Development Team at NASA Johnson Space Center has invested heavily in the advancement of rear-entry planetary exploration suit design but largely deferred development of extravehicular activity (EVA) glove designs, and accepted the risk of using the current flight gloves, Phase VI, for unique mission scenarios outside the Space Shuttle and International Space Station (ISS) Program realm of experience. However, as design reference missions mature, the risks of using heritage hardware have highlighted the need for developing robust new glove technologies. To address the technology gap, the NASA Game-Changing Technology group provided start-up funding for the High Performance EVA Glove (HPEG) Project in the spring of 2012. The overarching goal of the HPEG Project is to develop a robust glove design that increases human performance during EVA and creates pathway for future implementation of emergent technologies, with specific aims of increasing pressurized mobility to 60% of barehanded capability, increasing the durability by 100%, and decreasing the potential of gloves to cause injury during use. The HPEG Project focused initial efforts on identifying potential new technologies and benchmarking the performance of current state of the art gloves to identify trends in design and fit leading to establish standards and metrics against which emerging technologies can be assessed at both the component and assembly levels. The first of the benchmarking tests evaluated the quantitative mobility performance and subjective fit of four prototype gloves developed by Flagsuit LLC, Final Frontier Designs, LLC Dover, and David Clark Company as compared to the Phase VI. All of the companies were asked to design and fabricate gloves to the same set of NASA provided hand measurements (which corresponded to a single size of Phase Vi glove) and focus their efforts on improving mobility in the metacarpal phalangeal and carpometacarpal joints. Four test subjects representing the design ]to hand anthropometry completed range of motion, grip/pinch strength, dexterity, and fit evaluations for each glove design in both the unpressurized and pressurized conditions. This paper provides a comparison of the test results along with a detailed description of hardware and test methodologies used.

Aitchison, Lindsay↗