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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 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
NASA NTRS2006

Grism Performance for Mid-IR (5-40 microns) Spectroscopy

Grisms provide a straightforward method to transform an imager into a spectrometer with little change to the original imaging optics. This paper addresses the performance of a suite of grisms as part of an Astrobiology Science and Instrument Development (ASTID) Program to implement a moderate resolution spectroscopic capability to the mid/far-IR facility instrument FORCAST for the Stratospheric Observatory For Infrared Astronomy (SOFIA) [see accompanying abstract by Adams et al.]. A moderate resolution mid-IR spectrometer on SOFIA will offer advantages not available to either ground or space-based instruments after the Spitzer Space Telescope ceases operation in approx. 2007. SOFIA will begin operations in 2007 and will have an operational lifetime of approx. 20 years. From aircraft altitudes, it will be possible to cover a range of wavelengths, particularly in the critical 5-9 micron band, where detection of astrobiologically interesting molecules have key spectral signatures, that are not accessible from the ground. This grism suite consists of six grisms: four monolithic Si grisms [see accompanying abstract by Mar et al.] and two KRS-5 grisms. These devices will allow long slit low-resolution and short slit, cross-dispersed high-resolution spectroscopic modes selectable by simply moving the camera filter wheels. This configuration will enable observing programs to gather images and spectra in a single SOFIA flight. The four silicon grisms, whose performance is highlighted in this paper, will operate in the following wavelength ranges: 5-8, 17-28, and 28-37 microns. In the 5-8 micron range, R=1200 is achievable for a 2 arcsecond slit using the grism as a cross-disperser. For the 17-28 and 28-37 micron ranges, the resolving powers are R approx. 130, 250 when used in low orders with a slit of 3 arcseconds. The silicon grisms demonstrate a new family of dispersive elements with good optical performance for spectroscopy from 1.2-8 micron and beyond 18 microns. Furthermore, the FORCAST grism modes are close in wavelength coverage and resolving power to the Spitzer Infrared Spectrograph (IRS), so that among other possible observations, SOFIA can now enable follow-up studies of the brighter objects that Spitzer has observed and enable studies of sources that were too bright for observation with Spitzer.

Ennico, K. A.↗
NASA NTRS2003

Using Computational Cognitive Modeling to Diagnose Possible Sources of Aviation Error

We present a computational model of a closed-loop, pilot-aircraft-visual scene-taxiway system created to shed light on possible sources of taxi error. Creating the cognitive aspects of the model using ACT-R required us to conduct studies with subject matter experts to identify experiential adaptations pilots bring to taxiing. Five decision strategies were found, ranging from cognitively-intensive but precise, to fast, frugal but robust. We provide evidence for the model by comparing its behavior to a NASA Ames Research Center simulation of Chicago O'Hare surface operations. Decision horizons were highly variable; the model selected the most accurate strategy given time available. We found a signature in the simulation data of the use of globally robust heuristics to cope with short decision horizons as revealed by errors occurring most frequently at atypical taxiway geometries or clearance routes. These data provided empirical support for the model.

Pilots↗
NASA NTRS2000

Magnetically suspended miniature fluid pump and method of designing the same

A rotary pump for pumping fluids through a patient having a housing with an internal region, a stator member and an impeller positioned within the housing and having impeller blades, wherein the impeller is magnetically suspended and rotated, and wherein the geometric configuration of the rotary pump is sized and proportioned to minimize stagnant and traumatic fluid flow within the rotary pump. The plurality of magnetic impeller blades are preferably rare earth, high-energy-density magnets selected from the group consisting of samarium cobalt and neodymium-iron-boron alloy.

Antaki, James F.↗
NASA NTRS2008

Automated Generation and Assessment of Autonomous Systems Test Cases

This slide presentation reviews some of the issues concerning verification and validation testing of autonomous spacecraft routinely culminates in the exploration of anomalous or faulted mission-like scenarios using the work involved during the Dawn mission's tests as examples. Prioritizing which scenarios to develop usually comes down to focusing on the most vulnerable areas and ensuring the best return on investment of test time. Rules-of-thumb strategies often come into play, such as injecting applicable anomalies prior to, during, and after system state changes; or, creating cases that ensure good safety-net algorithm coverage. Although experience and judgment in test selection can lead to high levels of confidence about the majority of a system's autonomy, it's likely that important test cases are overlooked. One method to fill in potential test coverage gaps is to automatically generate and execute test cases using algorithms that ensure desirable properties about the coverage. For example, generate cases for all possible fault monitors, and across all state change boundaries. Of course, the scope of coverage is determined by the test environment capabilities, where a faster-than-real-time, high-fidelity, software-only simulation would allow the broadest coverage. Even real-time systems that can be replicated and run in parallel, and that have reliable set-up and operations features provide an excellent resource for automated testing. Making detailed predictions for the outcome of such tests can be difficult, and when algorithmic means are employed to produce hundreds or even thousands of cases, generating predicts individually is impractical, and generating predicts with tools requires executable models of the design and environment that themselves require a complete test program. Therefore, evaluating the results of large number of mission scenario tests poses special challenges. A good approach to address this problem is to automatically score the results based on a range of metrics. Although the specific means of scoring depends highly on the application, the use of formal scoring - metrics has high value in identifying and prioritizing anomalies, and in presenting an overall picture of the state of the test program. In this paper we present a case study based on automatic generation and assessment of faulted test runs for the Dawn mission, and discuss its role in optimizing the allocation of resources for completing the test program.

Testing challenges↗
NASA NTRS2009

A Micro Fluorescent Activated Cell Sorter for Astrobiology Applications

A micro-scale Fluorescent Activated Cell Sorter (microFACS) for astrobiology applications is under development. This device is designed to have a footprint of 7 cm x 7 cm x 4 cm and allow live-dead counts and sorting of cells that have fluorescent characteristics from staining. The FACS system takes advantage of microfluidics to create a cell sorter that can fit in the palm of the hand. A micron-scale channel allows cells to pass by a blue diode which causes emission of marker-expressed cells which are detected by a filtered photodetector. A small microcontroller then counts cells and operates high speed valves to select which chamber the cell is collected in (a collection chamber or a waste chamber). Cells with the expressed characteristic will be collected in the collection chamber. This system has been built and is currently being tested. We are also designing a system with integrated MEMS-based pumps and valves for a small and compact unit to fly on small satellite-based biology experiments.

Platt, Donald W.↗
NASA NTRS2001

Shuttle Safety Improvements

The Space Shuttle has been flying for over 20 years and based on the Orbiter design life of 100 missions it should be capable of flying at least 20 years more if we take care of it. The Space Shuttle Development Office established in 1997 has identified those upgrades needed to keep the Shuttle flying safely and efficiently until a new reusable launch vehicle (RLV) is available to meet the agency commitments and goals for human access to space. The upgrade requirements shown in figure 1 are to meet the program goals, support HEDS and next generation space transportation goals while protecting the country 's investment in the Space Shuttle. A major review of the shuttle hardware and processes was conducted in 1999 which identified key shuttle safety improvement priorities, as well as other system upgrades needed to reliably continue to support the shuttle miss ions well into the second decade of this century. The high priority safety upgrades selected for development and study will be addressed in this paper.

Henderson, Edward↗
NASA NTRS2010

Liquid Propulsion: Propellant Feed System Design

The propellant feed system of a liquid rocket engine determines how the propellants are delivered from the tanks to the thrust chamber. They are generally classified as either pressure fed or pump fed. The pressure-fed system is simple and relies on tank pressures to feed the propellants into the thrust chamber. This type of system is typically used for space propulsion applications and auxiliary propulsion applications requiring low system pressures and small quantities of propellants. In contrast, the pump-fed system is used for high pressure, high performance applications. The selection of one propellant feed system over another is determined based on design trade studies at both the engine and vehicle levels. This chapter first provides a brief overview of the basic configurations of pressure-fed systems. Pump-fed systems are then discussed with greater detail given to the turbomachinery design. Selected design requirements and configurations are provided.

Cannon, James L.↗
NASA NTRS2010

Ultra Reliable Closed Loop Life Support for Long Space Missions

Spacecraft human life support systems can achieve ultra reliability by providing sufficient spares to replace all failed components. The additional mass of spares for ultra reliability is approximately equal to the original system mass, provided that the original system reliability is not too low. Acceptable reliability can be achieved for the Space Shuttle and Space Station by preventive maintenance and by replacing failed units. However, on-demand maintenance and repair requires a logistics supply chain in place to provide the needed spares. In contrast, a Mars or other long space mission must take along all the needed spares, since resupply is not possible. Long missions must achieve ultra reliability, a very low failure rate per hour, since they will take years rather than weeks and cannot be cut short if a failure occurs. Also, distant missions have a much higher mass launch cost per kilogram than near-Earth missions. Achieving ultra reliable spacecraft life support systems with acceptable mass will require a well-planned and extensive development effort. Analysis must determine the reliability requirement and allocate it to subsystems and components. Ultra reliability requires reducing the intrinsic failure causes, providing spares to replace failed components and having "graceful" failure modes. Technologies, components, and materials must be selected and designed for high reliability. Long duration testing is needed to confirm very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The system must be designed, developed, integrated, and tested with system reliability in mind. Maintenance and reparability of failed units must not add to the probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass should start soon since it must be a long term effort.

Jones, Harry W.↗
NASA NTRS2011

Orion Flight Test-1 Thermal Protection System Instrumentation

The Orion Crew Exploration Vehicle (CEV) was originally under development to provide crew transport to the International Space Station after the retirement of the Space Shuttle, and to provide a means for the eventual return of astronauts to the Moon. With the current changes in the future direction of the United States human exploration programs, the focus of the Orion project has shifted to the project s first orbital flight test, designated Orion Flight Test 1 (OFT-1). The OFT-1 is currently planned for launch in July 2013 and will demonstrate the Orion vehicle s capability for performing missions in low Earth orbit (LEO), as well as extensibility beyond LEO for select, critical areas. Among the key flight test objectives are those related to validation of the re-entry aerodynamic and aerothermal environments, and the performance of the thermal protection system (TPS) when exposed to these environments. A specific flight test trajectory has been selected to provide a high energy entry beyond that which would be experienced during a typical low Earth orbit return, given the constraints imposed by the possible launch vehicles. This trajectory resulted from a trade study that considered the relative benefit of conflicting objectives from multiple subsystems, and sought to provide the maximum integrated benefit to the re-entry state-of-the-art. In particular, the trajectory was designed to provide: a significant, measureable radiative heat flux to the windward surface; data on boundary transition from laminar to turbulent flow; and data on catalytic heating overshoot on non-ablating TPS. In order to obtain the necessary flight test data during OFT-1, the vehicle will need to have an adequate quantity of instrumentation. A collection of instrumentation is being developed for integration in the OFT-1 TPS. In part, this instrumentation builds upon the work performed for the Mars Science Laboratory Entry, Descent and Landing Instrument (MEDLI) suite to instrument the OFT-1 ablative heat shield. The MEDLI integrated sensor plugs and pressure sensors will be adapted for compatibility with the Orion TPS design. The sensor plugs will provide in-depth temperature data to support aerothermal and TPS model correlation, and the pressure sensors will provide a flush air data system for validation of the entry and descent aerodynamic environments. In addition, a radiometer design will be matured to measure the radiative component of the reentry heating at two locations on the heat shield. For the back shell, surface thermocouple and pressure port designs will be developed and applied which build upon the heritage of the Space Shuttle Program for instrumentation of reusable surface insulation (RSI) tiles. The quantity and location of the sensors has been determined to balance the needs of the reentry disciplines with the demands of the hardware development, manufacturing and integration. Measurements which provided low relative value and presented significant engineering development effort were, unfortunately, eliminated. The final TPS instrumentation has been optimized to target priority test objectives. The data obtained will serve to provide a better understanding of reentry environments for the Orion capsule design, reduce margins, and potentially reduce TPS mass or provide TPS extensibility for alternative missions.

Kowal, T. John↗
NASA NTRS2011

An Update on Experimental Climate Prediction and Analysis Products Being Developed at NASA's Global Modeling and Assimilation Office

The Global Modeling and Assimilation Office at NASA's Goddard Space Flight Center is developing a number of experimental prediction and analysis products suitable for research and applications. The prediction products include a large suite of subseasonal and seasonal hindcasts and forecasts (as a contribution to the US National MME), a suite of decadal (10-year) hindcasts (as a contribution to the IPCC decadal prediction project), and a series of large ensemble and high resolution simulations of selected extreme events, including the 2010 Russian and 2011 US heat waves. The analysis products include an experimental atlas of climate (in particular drought) and weather extremes. This talk will provide an update on those activities, and discuss recent efforts by WCRP to leverage off these and similar efforts at other institutions throughout the world to develop an experimental global drought early warning system.

Schubert, Siegfried↗
NASA NTRS2012

CUBES Project Support

CUBES stands for Creating Understanding and Broadening Education through Satellites. The goal of the project is to allow high school students to build a small satellite, or CubeSat. Merritt Island High School (MIHS) was selected to partner with NASA, and California Polytechnic State University (Cal-Poly}, to build a CubeSat. The objective of the mission is to collect flight data to better characterize maximum predicted environments inside the CubeSat launcher, Poly-Picosatellite Orbital Deplorer (P-POD), while attached to the launch vehicle. The MIHS CubeSat team will apply to the NASA CubeSat Launch Initiative, which provides opportunities for small satellite development teams to secure launch slots on upcoming expendable launch vehicle missions. The MIHS team is working to achieve a test launch, or proof of concept flight aboard a suborbital launch vehicle in early 2013.

Jenkins, Kenneth T., Jr.↗
NASA NTRS2013

Flash Cracking Reactor for Waste Plastic Processing

Conversion of waste plastic to energy is a growing problem that is especially acute in space exploration applications. Moreover, utilization of heavy hydrocarbon resources (wastes, waxes, etc.) as fuels and chemicals will be a growing need in the future. Existing technologies require a trade-off between product selectivity and feedstock conversion. The objective of this work was to maintain high plastic-to-fuel conversion without sacrificing the liquid yield. The developed technology accomplishes this goal with a combined understanding of thermodynamics, reaction rates, and mass transport to achieve high feed conversion without sacrificing product selectivity. The innovation requires a reaction vessel, hydrocarbon feed, gas feed, and pressure and temperature control equipment. Depending on the feedstock and desired product distribution, catalyst can be added. The reactor is heated to the desired tempera ture, pressurized to the desired pressure, and subject to a sweep flow at the optimized superficial velocity. Software developed under this project can be used to determine optimal values for these parameters. Product is vaporized, transferred to a receiver, and cooled to a liquid - a form suitable for long-term storage as a fuel or chemical. An important NASA application is the use of solar energy to convert waste plastic into a form that can be utilized during periods of low solar energy flux. Unlike previous work in this field, this innovation uses thermodynamic, mass transport, and reaction parameters to tune product distribution of pyrolysis cracking. Previous work in this field has used some of these variables, but never all in conjunction for process optimization. This method is useful for municipal waste incinerator operators and gas-to-liquids companies.

Timko, Michael T.↗
NASA NTRS2017

Future Food Production System Development Pulling from Space Biology Crop Growth Testing in Veggie

Preliminary crop testing using Veggie indicates the environmental conditions provided by the ISS are generally suitable for food crop production. When plant samples were returned to Earth for analysis, their levels of nutrients were comparable to Earth-grown ground controls. Veggie-grown produce food safety microbiology analysis indicated that space-grown crops are safe to consume. Produce sanitizing wipes were used on-orbit to further reduce risk of foodborne illness. Validation growth tests indicated abiotic challenges of insufficient or excess fluid delivery, potentially reduced air flow leading to excess water, elevated CO2 leading to physiological responses, and microorganisms that became opportunistic pathogens. As NASA works to develop future space food production, several areas of research to define these systems pull from the Veggie technology validation tests. Research into effective, reusable water delivery and water recovery methods for future food production systems arises from abiotic challenges observed. Additionally, impacts of elevated CO2 and refinement of fertilizer and light recipes for crops needs to be assessed. Biotic pulls include methods or technologies to effectively sanitize produce with few consumables and low inputs; work to understand the phytomicrobiome and potentially use it to protect crops or enhance growth; selection of crops with high harvest index and desirable flavors for supplemental nutrition; crops that provide psychosocial benefits, and custom space crop development. Planning for future food production in a deep space gateway or a deep space transit vehicle requires methods of handling and storing seeds, and ensuring space seeds are free of contaminants and long-lived. Space food production systems may require mechanization and autonomous operation, with preliminary testing initiated to identify operations and capabilities that are candidates for automation. Food production design is also pulling from Veggie logistics lessons, as we learn about growing at different scales and move toward developing systems that require less launch mass. Veggie will be used as a test bed for novel food production technologies. Veggie is a relatively simple precursor food production system but the knowledge gained from space biology validation tests in Veggie will have far reaching repercussions on future exploration food production.

Veggie↗
NASA NTRS2017

Future Food Production System Development Pulling From Space Biology Crop Growth Testing in Veggie

Preliminary crop testing using Veggie indicates the environmental conditions provided by the ISS are generally suitable for food crop production. When plant samples were returned to Earth for analysis, their levels of nutrients were comparable to Earth-grown ground controls. Veggie-grown produce food safety microbiology analysis indicated that space-grown crops are safe to consume. Produce sanitizing wipes were used on-orbit to further reduce risk of foodborne illness. Validation growth tests indicated abiotic challenges of insufficient or excess fluid delivery, potentially reduced air flow leading to excess water, elevated CO2 leading to physiological responses, and microorganisms that became opportunistic pathogens. As NASA works to develop future space food production, several areas of research to define these systems pull from the Veggie technology validation tests. Research into effective, reusable water delivery and water recovery methods for future food production systems arises from abiotic challenges observed. Additionally, impacts of elevated CO2 and refinement of fertilizer and light recipes for crops needs to be assessed. Biotic pulls include methods or technologies to effectively sanitize produce with few consumables and low inputs; work to understand the phytomicrobiome and potentially use it to protect crops or enhance growth; selection of crops with high harvest index and desirable flavors for supplemental nutrition; crops that provide psychosocial benefits, and custom space crop development. Planning for future food production in a deep space gateway or a deep space transit vehicle requires methods of handling and storing seeds, and ensuring space seeds are free of contaminants and long-lived. Space food production systems may require mechanization and autonomous operation, with preliminary testing initiated to identify operations and capabilities that are candidates for automation. Food production design is also pulling from Veggie logistics lessons, as we learn about growing at different scales and move toward developing systems that require less launch mass. Veggie will be used as a test bed for novel food production technologies. Veggie is a relatively simple precursor food production system but the knowledge gained from space biology validation tests in Veggie will have far reaching repercussions on future exploration food production. This work is supported by NASA.

Plants↗
NASA NTRS1996

Validation of the ASTER Thermal Infrared Surface Radiance Data Product

The Advanced Spaceborne Thermal Emission and reflection Radiometer (ASTER) is a 14 channel high spatial resolution instrument selected for flight on the EOS AM-1 platform...To provide an objective assessment of the validity of the atmospheric correction, in situ measurements of water surfaces under a variety of atmospheric conditions will be used to estimate the surface leaving radiance at the scale of an ASTER pixel... These measurements and the spectral emissivity of the water will be combined with the relative system spectral response to provide and estimater of thermal infrared surface leaving radiance for each ASTER thermal channel. An example of this approach using a multichannel thermal aircraft scanner as a stand in for ASTER will be described.

ASTER↗
NASA NTRSDate not supplied

Evaluating Microgreens Crop Readiness for Space Production

Microgreens are small-size, nutrient-rich, and fast-grown crops, which are considered as candidates for future space exploration missions. In particular, the ISS, the Lunar Gateway, and Mars and Lunar missions could benefit from growing microgreens to supplement astronaut diets in the near future. Research at NASA’s Kennedy Space Center has focused on (1) the selection of microgreens compatible species, (2) the evaluation of microgreens food safety, (3) the use of passive wicking, on-demand watering, and hydroponics cultivation, (4) simulated microgravity growth, (5) microgreen canopy gas exchange, and (6) harvesting techniques in microgravity. This interactive presentation summarizes this research. Microgreen species will be evaluated for their yield in relationship to the quantity of inputs – water, seeds, substrate, light intensity, photoperiod, crew time – required for their growth; for their organoleptic and sensory factors in order to down select species that are highly acceptable for humans; and for their microbial loads as detected in their growth environment and the food safety metrics of their edible tissue. Passive wicking, on-demand watering, and hydroponic systems are being studied as an efficient way to deliver essential nutrients and water to microgreens, included in a microgravity environment. Growth studies in simulated microgravity (using 3-dimensional clinostats) will assess microgreens growth relative to that in 1g. Gas exchange studies on microgreens canopies in various airflows will assess their photosynthesis and transpiration. Finally, a series of parabolic flights has enabled the evaluation of different harvesting and bagging techniques in microgravity. Indeed, traditional plant harvesting methods (scissors) in microgravity could generate significant microgreen debris in the space station cabin. Two innovative techniques, coupled to a dedicated bagging method, were designed and evaluated against the control, traditional, harvesting technique. This research was supported by grants from NASA KSC’s Independent Research and Technology Development Program, NASA’s Flight Opportunity Program, NASA Postdoctoral Program Fellowships (L.P. & C.J.) supported by NASA’s Space Biology program, and support from NASA’s Human Research Program.

Space Crop Production↗
NASA NTRSDate not supplied

Evaluating Microgreens Crop Readiness for Space Production.

Microgreens are small-size, nutrient-rich, and fast-grown crops, which are considered as candidates for future space exploration missions. In particular, the ISS, the Lunar Gateway, and Mars and Lunar missions could benefit from growing microgreens to supplement astronaut diets in the near future. Research at NASA’s Kennedy Space Center has focused on (1) the selection of microgreens compatible species, (2) the evaluation of microgreens food safety, (3) the use of passive wicking, on-demand watering, and hydroponics cultivation, (4) simulated microgravity growth, (5) microgreen canopy gas exchange, and (6) harvesting techniques in microgravity. This presentation summarizes this research. Microgreen species will be evaluated for their yield in relationship to the quantity of inputs – water, seeds, substrate, light intensity, photoperiod, crew time – required for their growth; for their organoleptic and sensory factors in order to down select species that are highly acceptable for humans; and for their microbial loads as detected in their growth environment and the food safety metrics of their edible tissue. Passive wicking, on-demand watering, and hydroponic systems are being studied as an efficient way to deliver essential nutrients and water to microgreens, included in a microgravity environment. Growth studies in simulated microgravity (using 3-dimensional clinostats) will assess microgreens growth relative to that in 1g. Gas exchange studies on microgreens canopies in various airflows will assess their photosynthesis and transpiration. Finally, a series of parabolic flights has enabled the evaluation of different harvesting and bagging techniques in microgravity. Indeed, traditional plant harvesting methods (scissors) in microgravity could generate significant microgreen debris in the space station cabin. Two innovative techniques, coupled to a dedicated bagging method, were designed and evaluated against the control, traditional, harvesting technique. This research was supported by grants from NASA KSC’s Independent Research and Technology Development Program, NASA’s Flight Opportunity Program, NASA Postdoctoral Program Fellowships (L.P. & C.J.) supported by NASA’s Space Biology program, and support from NASA’s Human Research Program.

crop↗