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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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ASE has successfully demonstrated that a spacecraft can be driven by science analysis and autonomously controlled. ASE is available for flight on other missions. Mission hardware design should consider ASE requirements for available onboard data storage, onboard memory size and processor speed.
On Oct. 1, 2001 Cleveland State University and NASA Glenn Research Center embarked on the above named cooperative agreement. Because NASA's research facilities often exhibit instances where the failure to use state-of-the-art technologies and methods to improve on outmoded systems of interface and control, and this runs contrary to the NASA philosophy of "faster, better, and cheaper", it was deemed an ideal opportunity for this collaboration. The main objectives of the proposed effort were to research and investigate the use of the latest technologies, methods, techniques, etc. which pertain to control and interface with industrial and research systems and facilities. The work was done in large part at NASA Glenn Research Center, using selected research facilities as real-world laboratories; such as certain Microgravity Science Division and Space Station projects. Microgravity Science Division at Glenn Research Center designs and builds experiments to be flown on the Space Shuttle and eventually on the International Space Station. Economy of space, weight, complexity, data storage, ergonomics, and many other factors present problems that also exist in industry. Many of the solutions can come from the same areas of study mentioned above.
Experimenters from the fluids, combustion, materials, and life science disciplines all use the microgravity environment of space to enhance their understanding of fundamental physical phenomena caused by disturbances from events such as spacecraft maneuvers, equipment operations, atmospheric drag, and (for manned flights) crew movement. Space conditions reduce gravity but do not eliminate it. To quantify the level of these disturbances, NASA developed the Space Acceleration Measurement System (SAMS) series to collect data characterizing the acceleration environment on the space shuttles. This information is provided to investigators so that they can evaluate how the microgravity environment affects their experiments. Knowledge of the microgravity environment also helps investigators to plan future experiments. The original SAMS system flew 20 missions on the shuttle as well as on the Russian space station Mir. Presently, Lewis is developing SAMS-II for the International Space Station; it will be a distributed system using digital output sensor heads. The latest operational version of SAMS, SAMS-FF, was originally designed for free flyer spacecraft and unmanned areas. SAMS-FF is a flexible, modular system, housed in a lightweight package, and it uses advances in technology to improve performance. The hardware package consists of a control and data acquisition module, three different types of sensors, data storage devices, and ground support equipment interfaces. Three different types of sensors are incorporated to measure both high- and low-frequency accelerations and the roll rate velocity. Small, low-power triaxial sensor heads (TSH's) offer high resolution and selectable bandwidth, and a special low-frequency accelerometer is available for high-resolution, low-frequency applications. A state-of-the-art, triaxial fiberoptic gyroscope that measures extremely low roll rates is housed in a compact package. The versatility of the SAMS-FF system is shown in the three different types of missions SAMS-FF has supported.
Soft ferromagnetic materials have thus far found the most utility in magnetic-MEMS, because the technologies necessary for depositing and micromachining them have been well developed previously by the data storage industry.
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An outstanding problem in spaceflight is the lack of adequate sensors for monitoring the space environment and its effects on engineering systems. By adequate, we mean low cost in terms of mission impact (e.g., low price, low mass/size, low power, low data rate, and low design impact). The New Millennium Program (NMP) is investigating the development of such a low-cost Space Environmental Monitor (SEM) package for inclusion on its technology validation flights. This effort follows from the need by NMP to characterize the space environment during testing so that potential users can extrapolate the test results to end-use conditions. The immediate objective of this effort is to develop a small diagnostic sensor package that could be obtained from commercial sources. Environments being considered are: contamination, atomic oxygen, ionizing radiation, cosmic radiation, EMI, and temperature. This talk describes the requirements and rational for selecting these environments and reviews a preliminary design that includes a micro-controller data logger with data storage and interfaces to the sensors and spacecraft. If successful, such a sensor package could be the basis of a unique, long term program for monitoring the effects of the space environment on spacecraft systems.
A tactile display device utilizes an electrorheological fluid to activate a plurality of tactile dots. A voltage is selectively produced uniformly across an electrorheological fluid flowing between a common ground electrode and a plurality of conductive dot electrodes, thereby producing an increase in the fluid's viscosity to the extent that fluid flow between the two electrodes is restricted. The flow restriction produces a build-up of electrorheological fluid in a corresponding dot actuator chamber. The resulting pressure increase in the chamber displaces an elastic diaphragm fixed to a display surface to form a lump which can be perceived by the reader as one dot in a Braille character cell. A flow regulation system provides a continually pressurized flow system and provides for free flow of the electrorheological fluid through the plurality of dot actuator chambers when they are not activated. The device is adaptable to printed circuit techniques and can simultaneously display tactile dots representative of a full page of Braille characters stored on a medium such as a tape cassette or to display tactile dots representative of non-Braille data appearing on a computer monitor or contained on another data storage medium. In an alternate embodiment, the elastic diaphragm drives a plurality of spring-loaded pins provided with positive stops to maintain consistent displacements of the pins in both their actuated and nonactuated positions.
A simulation process has been developed for generation of the longitudinal and lateral components of ground wind atmospheric turbulence as a function of mean wind speed, elevation, temporal frequency range and distance between locations. The distance between locations influences the spectral coherence between the simulated series at adjacent locations. Short distances reduce correlation only at high frequencies; as distances increase correlation is reduced over a wider range of frequencies. The choice of values for the constants d1 and d3 in the PSD model is the subject of work in progress. An improved knowledge of the values for zO as a function of wind direction at the ARES-1 launch pads is necessary for definition of d1. Results of other studies at other locations may be helpful as summarized in Fichtl's recent correspondence. Ideally, further research is needed based on measurements of ground wind turbulence with high resolution anemometers at a number of altitudes at a new KSC tower located closer to the ARES-1 launch pad .The proposed research would be based on turbulence measurements that may be influenced by surface terrain roughness that may be significantly different from roughness prior to 1970 in Fichtl's measurements. Significant improvements in instrumentation, data storage end processing will greatly enhance the capability to model ground wind profiles and ground wind turbulence.
European Space Agency Mission is designed to study the atmosphere and surface of Saturn's largest satellite, Titan carried by the Cassini spacecraft which provides: a) Power for support equipment; b) S-band antenna system; and c) Data storage and playback. Instruments/investigations include: 1) Aerosol Collector Pyrolyzer (ACP). Study of clouds and aerosols in the Titan atmosphere. 2) Descent Imager and Spectral Radiometer (DISR). Aerosol and cloud optical properties and spectroscopy measurements of Titan's atmosphere and surface. 3) Doppler Wind Experiment (DWE). Study of winds from their effect on the Probe during Titan descent. 4) Gas Chromatograph and Mass Spectrometer (GCMS). Chemical composition of gases and aerosols in Titan's atmosphere. 5) Huygens Atmospheric Structure Instrument (HASI). In-situ study of Titan atmospheric physical and electrical properties. 6) Surface Science Package (SSP). Physical properties of Titan's surface and related atmospheric properties.
The Balloon-borne Experiment with a Superconducting Spectrometer, BESS, has been developed to study elementary particle phenomena in the early universe through measurements of low energy antiprotons to investigate their origin and through a search for antihelium. The BESS collaboration carried out nine northern latitude flights between 1993 and 2002. BESS-Polar is an advanced program of the BESS collaboration to study these topics with much greater precision using long duration flights above Antarctica. The BESS-Polar spectrometer was successfully developed to accumulate much larger numbers of events during long duration flights around the South Pole. Approximately a factor of four reductions in the amount of material in the particle beam enables measurement of much lower energy antiprotons down to 100 MeV (at top of atmosphere). The first BESS-Polar flight (BESS-Polar I) of 8.5 days was carried out above Antarctica in December 2004. recording 900 million cosmic-ray events. The second BESS-Polar flight (BESS-Polar 11) was successfully carried out in the austral summer season of 2007-2008. Based on experience with BESS-Polar I, the spectrometer was improved in performance and achieved long term stability during the flight. A newly constructed magnet with a larger liquid He capacity and improved thermal insulation and an upgraded data storage system with larger capacity of hard disk drives (HDDs) enabled longer observation time. BESS-Polar II was launched on December 22, 2007 from Williams Field, McMurdo Station, in Antarctica. The spectrometer worked properly and observed cosmic rays for about 24.5 days at float altitude, recording 4.6 billion events on the HDDs until the limit of the magnet operation was reached on January 16, 2008. The flight was terminated and the spectrometer was safely landed on the West Antarctic ice sheet (1000 km from the South Pole) on January 21, 2008. Here, the BESS-Polar instrument is discussed, highlighting improvements made for BESS-Polar II, and overviews of the flight and performance are reported.
A document discusses placing memory modules on the high-speed serial interconnect, which is used by a spacecraft s computer elements for inter-processor communications, to allow all multiple computer system architectures to access the spacecraft data storage at the same time. Each memory board is identical electrically and receives its bus ID upon connection to the system. The computer elements are configured in a similar fashion. The architecture allows for multiple memory boards to be accessed simultaneously by different computer elements, and results in a scalable, strong, fault-tolerant system. The IEEE-1393 ring bus can be routed so that multiple card failures can occur and the mass memory storage will still function.
An outstanding problem in spaceflight is the lack of adequate sensors for monitoring the space environment and its effects on engineering systems. By adequate, we mean low cost in terms of mission impact (e.g., low price, low mass/size, low power, low data rate, and low design impact). The New Millennium Program (NMP) is investigating the development of such a low-cost Space Environmental Monitor (SEM) package for inclusion on its technology validation flights. This effort follows from the need by NMP to characterize the space environment during testing so that potential users can extrapolate the test results to end-use conditions. The immediate objective of this effort is to develop a small diagnostic sensor package that could be obtained from commercial sources. Environments being considered are: contamination, atomic oxygen, ionizing radiation, cosmic radiation, EMI, and temperature. This talk describes the requirements and rational for selecting these environments and reviews a preliminary design that includes a micro-controller data logger with data storage and interfaces to the sensors and spacecraft. If successful, such a sensor package could be the basis of a unique, long term program for monitoring the effects of the space environment on spacecraft systems.
Future in-space and lunar operations will require significantly improved monitoring and Integrated System Health Management (ISHM) throughout the mission. In particular, the monitoring of chemical species is an important component of an overall monitoring system for space vehicles and operations. For example, in leak monitoring of propulsion systems during launch, inspace, and on lunar surfaces, detection of low concentrations of hydrogen and other fuels is important to avoid explosive conditions that could harm personnel and damage the vehicle. Dependable vehicle operation also depends on the timely and accurate measurement of these leaks. Thus, the development of a sensor array to determine the concentration of fuels such as hydrogen, hydrocarbons, or hydrazine as well as oxygen is necessary. Work has been on-going to develop an integrated smart leak detection system based on miniaturized sensors to detect hydrogen, hydrocarbons, or hydrazine, and oxygen. The approach is to implement Microelectromechanical Systems (MEMS) based sensors incorporated with signal conditioning electronics, power, data storage, and telemetry enabling intelligent systems. The final sensor system will be self-contained with a surface area comparable to a postage stamp. This paper discusses the development of this "Lick and Stick" leak detection system and it s application to In-Space Transportation and other Exploration applications.
In recent years, hardware-in-the-loop (HIL) testing has carved a strong niche in several industries, such as automotive, aerospace, telecomm, and consumer electronics. As desktop computers have realized gains in speed, memory size, and data storage capacity, hardware/software platforms have evolved into high performance, deterministic HIL platforms, capable of hosting the most demanding applications for testing components and subsystems. Using simulation software to emulate the digital and analog I/O signals of system components, engineers of all disciplines can now test new systems in realistic environments to evaluate their function and performance prior to field deployment. Within the Aerospace industry, space-borne satellite systems are arguably some of the most demanding in terms of their requirement for custom engineering and testing. Typically, spacecraft are built one or few at a time to fulfill a space science or defense mission. In contrast to other industries that can amortize the cost of HIL systems over thousands, even millions of units, spacecraft HIL systems have been built as one-of-a-kind solutions, expensive in terms of schedule, cost, and risk, to assure satellite and spacecraft systems reliability. The focus of this paper is to present a new approach to HIL testing for spacecraft systems that takes advantage of a highly flexible hardware/software architecture based on National Instruments PXI reconfigurable hardware and virtual instruments developed using LabVIEW. This new approach to HIL is based on a multistage/multimode spacecraft bus emulation development model called Reconfigurable Hardware In-the-Loop or RHIL.
This software generates high-quality plans for carrying out mine-sweeping activities under resource constraints. The autonomous planning and replanning system for unmanned underwater vehicles (UUVs) takes as input a set of prioritized mine-sweep regions, and a specification of available UUV resources including available battery energy, data storage, and time available for accomplishing the mission. Mine-sweep areas vary in location, size of area to be swept, and importance of the region. The planner also works with a model of the UUV, as well as a model of the power consumption of the vehicle when idle and when moving.
As an early proponent of grid computing, Ames Research Center awarded Small Business Innovation Research (SBIR) funding to 3DGeo Development Inc., of Santa Clara, California, (now FusionGeo Inc., of The Woodlands, Texas) to demonstrate a virtual computer environment that linked geographically dispersed computer systems over the Internet to help solve large computational problems. By adding to an existing product, FusionGeo enabled access to resources for calculation- or data-intensive applications whenever and wherever they were needed. Commercially available as Accelerated Imaging and Modeling, the product is used by oil companies and seismic service companies, which require large processing and data storage capacities.
The Acquisition and Curation Office at JSC has undertaken a 4-year data restoration project effort for the lunar science community funded by the LASER program (Lunar Advanced Science and Exploration Research) to digitize photographs of the Apollo lunar rock samples and create high resolution digital images. These sample photographs are not easily accessible outside of JSC, and currently exist only on degradable film in the Curation Data Storage Facility
This paper gives a description of OPC (Object Linking and Embedding for Process Control) standards for process control and outlines the experiences at JSC with using these standards to interface with I/O hardware from three independent vendors. The I/O hardware was integrated with a commercially available SCADA/HMI software package to make up the control and monitoring system for the Environmental Systems Test Stand (ESTS). OPC standards were utilized for communicating with I/O hardware and the software was used for implementing monitoring, PC-based distributed control, and redundant data storage over an Ethernet physical layer using an embedded din-rail mounted PC.