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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,423 records · Page 79
All sourcesNASA NTRSDOE OSTI
NASA NTRS1991

Lessons learned from Space Shuttle flight software and Mission Control software

The techniques utilized by NASA to manage risk in the development and operations of flight software and Mission Control Center software for the Space Shuttle are reviewed. Particular attention is given to independent software in the backup flight system, structured requirements and design techniques, multiple levels of testing in development and production, independent testing following production, and independence of development and production, and the Mission Control Center model for Real Time Data System project.

Muratore, John F.↗
NASA NTRS1991

The Space Flight Operations Center first phase - Lessons learned

This paper is a retrospective look at the Space Flight Operations Center Project; a large, complex, multimission ground data system which is currently under development at the Jet Propulsion Laboratory (JPL), Pasadena. The Project was established in February 1984 and will be completed in April 1992 when the Magellan, Voyager, Ulysses, Galileo and Mars Observer Projects will be fully supported. The first phase of this project covers the development of a subset of multimission Baseline subsystems, the development of the mission-specific adaptations to this Baseline set for the Magellan Project, the development of a Magellan-specific high rate processor together with the delivery of these subsystems to operations. This first phase became operational in January 1989 in readiness for the Magellan launch in May 1989.

Gainsborough, A. J.↗
NASA NTRS1992

Lessons learned from the Autonomous Power System

The Autonomous Power System (APS) project at the NASA Lewis Research Center is designed to demonstrate the applications of integrated intelligent diagnosis, control and scheduling techniques to space power distribution systems. The project consists of three elements: the Autonomous Power Expert System (APEX) for Fault Diagnosis, Isolation, and Recovery (FDIR); the Autonomous Intelligent Power Scheduler (AIPS) to efficiently assign activities start times and resources; and power hardware (Brassboard) to emulate a space-based power system. The APS project had been through one design iteration. Each of the three elements of the APS project has been designed, tested, and integrated into a complete working system. After these three portions were completed, an evaluation period was initiated. Each piece of the system was critiqued based on individual performance as well as the ability to interact with the other portions of the APS project. These critiques were then used to determine guidelines for new and improved components of the APS system.

Ringer, Mark J.↗
NASA NTRS1991

Spatial orientation and dynamics in virtual reality systems - Lessons from flight simulation

Artificial representations of virtual worlds are becoming more common due to advances in the technology of image generation and display systems. Application areas include flight simulation, mission rehearsal, teleoperator systems, and virtual reality systems. System developers should be forewarned that some proportion of users will experience perceptual anomalies and symptoms of motion sickness as a result of travel through virtual space.

Mccauley, Michael E.↗
NASA NTRS1992

Testing primates with joystick-based automated apparatus - Lessons from the Language Research Center's Computerized Test System

Nonhuman primates provide useful models for studying a variety of medical, biological, and behavioral topics. Four years of joystick-based automated testing of monkeys using the Language Research Center's Computerized Test System (LRC-CTS) are examined to derive hints and principles for comparable testing with other species - including humans. The results of multiple parametric studies are reviewed, and reliability data are presented to reveal the surprises and pitfalls associated with video-task testing of performance.

Washburn, David A.↗
NASA NTRS1993

Launches and the environment - Lessons learned

An evaluation is presented of the consequences of NASA's study of the ways in which the launch of a Space Shuttle generates a plume of HCl and Al2O3; in combination with water from the Shuttle's sound-suppressor cooling water system, these substances can create a corrosive and hard-to-remove Al2O3 coating on nearby surfaces. Attention is given to the site-specific character of such environmental complications, the need to involve environmental-risk specialists in hardware-development teams, and the nonlinearity of many environmental impacts.

Vaughan, William W.↗
NASA NTRS1992

The Soft X-ray Telescope for Solar-A - Design evolution and lessons learned

The Japanese Solar-A satellite mission's Soft X-ray Telescope uses grazing-incidence optics, a CCD detector, and a pair of filter wheels for wavelength selection. A coaxially-mounted visible-light lens furnished sunspot and magnetic plage images, together with aspect information which aids in aligning the soft X-ray images with those from the satellite's Hard X-ray Telescope. Instrument electronics are microprocessor-based, and imbedded in a tightly integrated distributed system. Control software is divided between the instrument microprocessor and the spacecraft control computer.

Bruner, Marilyn E.↗
NASA NTRS1922

Lessons of the glider meets

While light loading was assumed to be the optimal conformation from previous meets, subsequent meets have shown that heavier loading produced better results.

Warner, Edward P↗
NASA NTRS1988

Lessons learned from an Ada conversion project

Recognizing the importance of building software with the robustness to accommodate rapid advances in technology, developers have focused on methods which preserve both past and future investment in software and in providing an advanced software engineering environment that frees the engineer, to the greatest extent possible, from the more routine aspects of software design and development. The software engineer is permitted to concentrate on the creative aspects of problem resolution. Standard languages such as Ada maximize portability across hardware and operating systems. Standard interfaces which enhance portability and permit the incorporation of new technology as it becomes available have been developed. Software design and development techniques which maximize portability receive increasing emphasis. Experience gained in porting an Ada application between two widely varying environments is evaluated in light of current practices to maximize software portability.

Porter, Tim↗
NASA NTRS1992

Experimental software engineering: Seventeen years of lessons in the SEL

Seven key principles developed by the Software Engineering Laboratory (SEL) at the Goddard Space Flight Center (GSFC) of the National Aeronautics and Space Administration (NASA) are described. For the past 17 years, the SEL has been experimentally analyzing the development of production software as varying techniques and methodologies are applied in this one environment. The SEL has collected, archived, and studied detailed measures from more than 100 flight dynamics projects, thereby gaining significant insight into the effectiveness of numerous software techniques, as well as extensive experience in the overall effectiveness of 'Experimental Software Engineering'. This experience has helped formulate follow-on studies in the SEL, and it has helped other software organizations better understand just what can be accomplished and what cannot be accomplished through experimentation.

Mcgarry, Frank E.↗
NASA NTRS1993

Some lessons learned in three years with ADS-33C

Three years of using the U.S. Army's rotorcraft handling qualities specification, Aeronautical Design Standard - 33, has shown it to be surprisingly robust. It appears to provide an excellent basis for design and for assessment, however, as the subtleties become more well understood, several areas needing refinement became apparent. Three responses to these needs have been documented in this paper: (1) The yaw-axis attitude quickness for hover target acquisition and tracking can be relaxed slightly. (2) Understanding and application of criteria for degraded visual environments needed elaboration. This and some guidelines for testing to obtain visual cue ratings have been documented. (3) The flight test maneuvers were an innovation that turned out to be very valuable. Their extensive use has made it necessary to tighten definitions and testing guidance. This was accomplished for a good visual environment and is underway for degraded visual environments.

Key, David L.↗
NASA NTRS1988

Science Operation in Space: Lessons

This program (conceived by a group of veteran Shuttle astronauts) shows prospective experimenters how they can better design their experiments for operation onboard Shuttle flights. Shuttle astronauts Dunbar, Seddon, Hoffman, Cleave, Ross, and ChangDiaz also show how crews live and work in space.

Source record↗
NASA NTRS1994

Handbook for handling and storage of nickel-cadmium batteries: Lessons learned

The handbook provides guidelines for the handling and storage of conventional NiCd flight batteries. The guidelines are based on many years of experience with ground and in-flight handling of batteries. The overall goal is to minimize the deterioration and irreversible effects of improper handling of NiCd flight batteries on flight performance. A secondary goal is to provide the reader with an understanding, in nonanalytical terms, of the degradation mechanisms of NiCd cells and how these mechanisms are affected by improper ground handling of flight hardware. Section 2 provides the reader with a brief introduction to NiCd cells. The effects of the environment on NiCd batteries are discussed in Section 3, and Section 4 contains 12 guidelines for battery handling and storage with supporting rationale for each guideline. The appendix provides a synopsis of NiCd cell design and evolution over 30 years of space flight on Goddard Space Flight Center (GSFC) satellites, along with a chronological review of key events that influenced the design of NiCd cells being flown today.

Ford, Floyd E.↗
NASA NTRS1994

La Chalupa-30: Lessons learned from a 30-day subsea mission analogue

The Behavior and Performance Laboratory (BPL) utilizes space mission analogs to study issues such as the psychological health and well-being, team characteristics, and task performance of crew members on long-duration missions. The analog used in this investigation was an underwater habitat named La Chalupa, which was selected for its similar features to a space station environment. The primary objectives of the La Chalupa-30 investigation were to evaluate the efficiency of several methods for collecting data in remote environments and to assess aspects of living and working under isolated and confined conditions.

Vanderark, Steve↗
NASA NTRS1993

Benefits gained and lessons learned from NASA's Small Explorer (SMEX) Program

NASA's Small Explorer Program (SMEX) is a sustained program of scientific satellites limited in mass to 200-300 kg (depending on orbital inclination) for a 500-km circular orbit. The SMEX program was undertaken to obtain the benefits of scientific yield, short development time, and high flight rate, with the goal to launch a mission every year. NASA also uses the program to train engineers and managers in designing and developing spacecraft. The phases of a SMEX mission life cycle are described including the competitive selection of missions through announcement of opportunity and evaluation of proposals, the definition of mission and system requirements, design and development of the spacecraft, testing, launch, and operations. Program content of some SMEX missions is then reviewed. The first SMEX mission was the Solar, Anomalous, and Magnetospheric Particle Explorer, which confirmed that anomalous cosmic rays are only partially ionized atoms. The Fast Auroral Snapshot Explorer was intended to measure the electric, magnetic, and time-variable fields and to record particle flow in the auroral acceleration region. A future mission is the Submillimeter Wave Astronomy Satellite to examine low-level molecular transitions.

Gilman, David↗
NASA NTRS1994

Pigeonholing planetary meteorites: The lessons of misclassification of EET87521 and ALH84001

The last few years have provided two noteworthy examples of misclassifications of achondritic meteorites because the samples were new kinds of meteorites from planetary rather than asteroidal parent bodies. Basaltic lunar meteorite EET87521 was misclassified as a eucrite and SNC (martian) orthopyroxenite ALH84001 was misclassified as a diogenite. In classifying meteorites we find what we expect: we pigeonhole meteorites into known categories most of which were derived from the more common asteroidal meteorites. But the examples of EET8752 and ALH84001 remind us that planets are more complex than asteroids and exhibit a wider variety of rock types. We should expect variety in planetary meteorites and we need to know how to recognize them when we have them. Our intent here is to show that our asteroidal perspective is inappropriate for planetary meteorites.

Lindstrom, M. M.↗