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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 1,621 records · Page 90
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NASA NTRS1992

Martian sedimentary deposits

The objectives are characterization of flow through outflow channels, sedimentation associated with Martian outflow systems, and documentation of Martian lakes. Over the period of the grant much, but not all, of the study centered on the Maja Valles outflow. Maja served as an example in which the effects of multiple channel routing and ponding could be studied. Maja Valles also served as the test case for calculating flow through an outflow system. Applying the lessons learned in Maja Valles and comparisons and contrast required a scrutiny of other channels.

Dehon, Rene↗
NASA NTRS1993

Recent advances and plans in processing and geocoding of SAR data at the DFD

Because of the needs of future projects like ENVISAT and the experiences made with the current operational ERS-1 facilities, a radical change in the synthetic aperture radar (SAR) processing scenarios can be predicted for the next years. At the German PAF several new developments were initialized which are driven mainly either by user needs or by system and operational constraints ('lessons learned'). At the end there will be a major simplification and uniformation of all used computer systems. Especially the following changes are likely to be implemented at the German PAF: transcription before archiving, processing of all standard products with high throughput directly at the receiving stations, processing of special 'high-valued' products at the PAF, usage of a single type of processor hardware, implementation of a large and fast on-line data archive, and improved and unified fast data network between the processing and archiving facilities. A short description of the current operational SAR facilities as well as the future implementations are given.

Noack, W.↗
NASA NTRS1993

New health and safety initiatives at the Department of Energy (DOE)

This document touches on some of the more important lessons learned and the more noteworthy initiatives DOE has put into motion in the last three years to protect the health and safety of our contractor employees. What we have learned in the process should come as no surprise to those of you who have been working in the field: (1) that management commitment to safety and health is critical to a successful program; (2) that meaningful employee participation in all aspects of the program enhances its effectiveness at every level; and (3) that the dedication and expertise of medical and occupational safety and health professionals are needed if the challenging problems presented by the complex and technologically advanced environment at DOE facilities are to be overcome. I believe that we have made a good beginning in the long and arduous task of building an Occupational Safety and Health Program that will serve as a model for others, and I can assure you that we intend to continue our efforts to protect every worker within the complex from occupational injury and disease.

Ziemer, Paul L.↗
NASA NTRS1993

California Student Get Away Special Payload GAS-450

The California Student Get Away Special Payload GAS-450, recently went into orbit on the STS-57 Mission, Space Shuttle, Endeavour, 21 June 1993, 6:14 AM and landed on the 29 June 1993 at Kennedy Space Center (KSC). Fifty students from 13 California Central Coast Schools and one in San Francisco designed and built 13 active experiments (6 modules) for this mission. Preliminary analysis of our completely reusable payload bus system indicated that the structure, power system, microprocessor, and sensor systems in each experiment module worked flawlessly. The experiments themselves performed exceptionally well with a 60 percent success ratio. The students are thoroughly documenting their own experiments and results via a standard research paper guideline generated by the GAS-450 technical staff. Lessons learned (program management and technical) are documented at the end of the paper. If any other organization needs payload/experiment development or NASA documentation assistance, then please contact us. We can help make your idea a space tested reality. Three years of intense effort culminated on 3 February 1993, the GSFC field operations team at Kennedy Space Center performed the final pressure decay and electrical tests upon the fully integrated GAS-450 flight canister. Subsequently, the payload was integrated with its parent GAS Bridge Assembly in mid-February and the bridge was transferred to the KSC orbiter team in late February 1993. The STS-57 mission originally scheduled to launch on the 29 April 1993 slipped until 21 June 1993. Our Payload shared the cargo bay with ten other GAS Canisters, the EUREKA experiment, the SHOOT experiment, and the SPACEHAB-1 module. The SIL technical staff retrieved the GAS-450 payload after flight from the NASA Spin Test Facility at KSC and shipped it back to California on the 22 July 1993 for student analysis at Allan Hancock College this summer.

Ray, Glen↗
NASA NTRS1993

Kennedy Space Center processing of Shuttle small payloads

There are many steps involved in preparing a payload for a mission into space on the Space Shuttle. Operations at the John F. Kennedy Space Center (KSC) are the last of those steps for the hardware before the payload is launched. To assure a successful and efficient KSC processing flow, a great deal of planning between the Robert H. Goddard Space Flight Center (GSFC) and KSC personnel is required before the payload arrives at KSC. After arrival, pre-flight operations occur between payload personnel, GSFC personnel, and KSC personnel for integration of the payload into its carrier (if required), in preparation for installation into a Orbiter. Once installed into an Orbiter, final test(s), checkout, and close-out of the payload is performed by GSFC and KSC personnel before launch. Mission support varies depending on the payload flying, but once the mission is complete and the Orbiter has returned to KSC, post-flight operations begin. This usually involves a reverse flow of the pre-flight operations. KSC operations conclude when the payload, its ground support equipment (GSE), and personnel depart KSC. A list of lessons learned is generated at the end of each payload flow, to avoid repeating the same mistakes (if any) for the next payload or for multiple repeat flights of the same payload. Always monitored are planned changes that may affect the payloads, GSE, KSC facilities, payload personnel, GSFC personnel, and/or KSC personnel.

Haddad, Michael E.↗
NASA NTRS1993

Utilization of Shuttle small payload accommodations in the DOD Space Test Program

Over the past 27 years, the U.S. Air Force, as executive agent for the Department of Defense (DOD) Space Test Program, has flown approximately 325 space experiments for the Army, Navy, Air Force, and other DOD agencies. These experiments have made significant contributions to the improvement of military technology and operations. Flight of Space Test Program experiments has been carried out utilizing free flyer spacecraft, the Space Shuttle crew cabin, and the Space Shuttle cargo bay. This paper will concentrate on those experiments which have been flown by the NASA Space Shuttle small payload flight systems, e.g., GAS, uprated GAS (CAP), and Hitchhiker flight systems. Discussions of Space Test Program experiments flown by Space Shuttle small payloads flight systems will include the experiment objectives, the accommodations and services provided by the flight systems, experiment results, and lessons learned from the planning and conduct of the flight. Particular emphasis will be placed on those experiments which required and were provided with a new and unique capability by the small payloads flight systems. These capabilities include the first use of the GAS opening lid, the first use of the GAS payload ejection capability, and the first use of the Hitchhiker cross bay carrier.

Hagler, Thomas↗
NASA NTRS1993

Superfluid Helium On-Orbit Transfer (SHOOT) flight demonstration

The Superfluid Helium On-Orbit Transfer (SHOOT) Flight Demonstration was an attached Shuttle payload mounted on a Hitchhiker cross-bay carrier which flew on STS-57 in June of 1993. SHOOT successfully demonstrated the handling and transfer of superfluid helium between two containers, called dewars, in low gravity. SHOOT was a class C payload and for the STS-57 mission was termed a complex secondary payload. The primaries were the retrieval of the EURECA carrier and a collection of modular experiments contained in SPACEHAB. Because the liquid helium was continuously boiling off, SHOOT's activities were scheduled for the first three days of the mission, concurrent with some SPACEHAB experiments, but well before the EURECA retrieval. Control of the SHOOT experiment was highly interactive and originated primarily from the Goddard Payload Operations and Control Center (POCC). Transfer and calibration activities required continuous command windows of up to 50 minutes duration and up to 80 minutes out of each orbit. Occasionally the crew controlled the experiment using the Payload General Support Computer (PGSC) when near-real time control and monitoring was required. SHOOT also placed considerable demands on the orbiter, including a pitch rotation of 3 deg./sec for 15 minutes, and translational burns using both the aft and forward RCS jets to generate accelerations up to 7 milli-g. The basis for these and other requirements are discussed. Interacion with the crew and timing of crew activity during the mission will be detailed. The processing flow of SHOOT at KSC is described with emphasis on the tradeoffs for vertical, as opposed to horizontal, installation in the orbiter. Finally, some lessons learned are presented that are relevant to future cryogenic and Hitchhiker payloads.

Shirron, Peter↗
NASA NTRS1993

An ASIC memory buffer controller for a high speed disk system

The need for large capacity, high speed mass memory storage devices has become increasingly evident at NASA during the past decade. High performance mass storage systems are crucial to present and future NASA systems. Spaceborne data storage system requirements have grown in response to the increasing amounts of data generated and processed by orbiting scientific experiments. Predictions indicate increases in the volume of data by orders of magnitude during the next decade. Current predictions are for storage capacities on the order of terabits (Tb), with data rates exceeding one gigabit per second (Gbps). As part of the design effort for a state of the art mass storage system, NASA Langley has designed a 144 CMOS ASIC to support high speed data transfers. This paper discusses the system architecture, ASIC design and some of the lessons learned in the development process.

Hodson, Robert F.↗
NASA NTRS1993

Developing a space network interface simulator: The NTS approach

This paper describes the approach used to redevelop the Network Control Center (NCC) Test System (NTS), a hardware and software facility designed to make testing of the NCC Data System (NCCDS) software efficient, effective, and as rigorous as possible prior to operational use. The NTS transmits and receives network message traffic in real-time. Data transfer rates and message content are strictly controlled and are identical to that of the operational systems. NTS minimizes the need for costly and time-consuming testing with the actual external entities (e.g., the Hubble Space Telescope (HST) Payload Operations Control Center (POCC) and the White Sands Ground Terminal). Discussed are activities associated with the development of the NTS, lessons learned throughout the project's lifecycle, and resulting productivity and quality increases.

Hendrzak, Gary E.↗
NASA NTRS1993

Publication of science data on CD-ROM: A guide and example

CD-ROM (Compact Disk-Read Only Memory) is becoming the standard media not only in audio recording, but also in the publication of data and information accessible on many computer platforms. Little has been written about the complicated process involved in creating easy-to-use, high quality, and useful CD-ROM's containing scientific data. This document is a manual designed to aid those who are responsible for the publication of scientific data on CD-ROM. All aspects and steps of the procedure are covered, from feasibility assessment through disk design, data preparation, disc mastering, and CD-ROM distribution. General advice and actual examples are based on lessons learned from the publication of scientific data for an interdisciplinary field experiment. Appendices include actual files from a CD-ROM, a purchase request for CD-ROM mastering services, and the disk art for the first disk published for the project.

Angelici, Gary↗
NASA NTRS1992

The application of artificial intelligence to astronomical scheduling problems

Efficient utilization of expensive space- and ground-based observatories is an important goal for the astronomical community; the cost of modern observing facilities is enormous, and the available observing time is much less than the demand from astronomers around the world. The complexity and variety of scheduling constraints and goals has led several groups to investigate how artificial intelligence (AI) techniques might help solve these kinds of problems. The earliest and most successful of these projects was started at Space Telescope Science Institute in 1987 and has led to the development of the Spike scheduling system to support the scheduling of Hubble Space Telescope (HST). The aim of Spike at STScI is to allocate observations to timescales of days to a week observing all scheduling constraints and maximizing preferences that help ensure that observations are made at optimal times. Spike has been in use operationally for HST since shortly after the observatory was launched in Apr. 1990. Although developed specifically for HST scheduling, Spike was carefully designed to provide a general framework for similar (activity-based) scheduling problems. In particular, the tasks to be scheduled are defined in the system in general terms, and no assumptions about the scheduling timescale are built in. The mechanisms for describing, combining, and propagating temporal and other constraints and preferences are quite general. The success of this approach has been demonstrated by the application of Spike to the scheduling of other satellite observatories: changes to the system are required only in the specific constraints that apply, and not in the framework itself. In particular, the Spike framework is sufficiently flexible to handle both long-term and short-term scheduling, on timescales of years down to minutes or less. This talk will discuss recent progress made in scheduling search techniques, the lessons learned from early HST operations, the application of Spike to other problem domains, and plans for the future evolution of the system.

Johnston, Mark D.↗
NASA NTRS1993

Link monitor and control operator assistant: A prototype demonstrating semiautomated monitor and control

This article describes the approach, results, and lessons learned from an applied research project demonstrating how artificial intelligence (AI) technology can be used to improve Deep Space Network operations. Configuring antenna and associated equipment necessary to support a communications link is a time-consuming process. The time spent configuring the equipment is essentially overhead and results in reduced time for actual mission support operations. The NASA Office of Space Communications (Code O) and the NASA Office of Advanced Concepts and Technology (Code C) jointly funded an applied research project to investigate technologies which can be used to reduce configuration time. This resulted in the development and application of AI-based automated operations technology in a prototype system, the Link Monitor and Control Operator Assistant (LMC OA). The LMC OA was tested over the course of three months in a parallel experimental mode on very long baseline interferometry (VLBI) operations at the Goldstone Deep Space Communications Center. The tests demonstrated a 44 percent reduction in pre-calibration time for a VLBI pass on the 70-m antenna. Currently, this technology is being developed further under Research and Technology Operating Plan (RTOP)-72 to demonstrate the applicability of the technology to operations in the entire Deep Space Network.

Lee, L. F.↗
NASA NTRS1994

Catalog of Apollo experiment operations

This catalog reviews Apollo mission reports, preliminary science reports, technical crew debriefings, lunar surface operations plans, and various relevant lunar experiment documents, collecting engineering- and operation-specific information by experiment. It is organized by discrete experimental and equipment items emplaced or operated on the lunar surface or at zero gravity during the Apollo missions. It also attempts to summarize some of the general problems encountered on the surface and provides guidelines for the design of future lunar surface experiments with an eye toward operations. Many of the problems dealt with on the lunar surface originated from just a few novel conditions that manifested themselves in various nasty ways. Low gravity caused cables to stick up and get caught on feet, and also made it easy for instruments to tip over. Dust was a problem and caused abrasion, visibility, and thermal control difficulties. Operating in a pressure suit limited a person's activity, especially in the hands. I hope to capture with this document some of the lessons learned from the Apollo era to make the jobs of future astronauts, principle investigators, engineers, and operators of lunar experiments more productive.

Sullivan, Thomas A.↗
NASA NTRS1993

Evolving directions in NASA's planetary rover requirements and technology

The evolution of NASA's planning for planetary rovers (that is robotic vehicles which may be deployed on planetary bodies for exploration, science analysis, and construction) and some of the technology that was developed to achieve the desired capabilities is reviewed. The program is comprised of a variety of vehicle sizes and types in order to accommodate a range of potential user needs. This includes vehicles whose weight spans a few kilograms to several thousand kilograms; whose locomotion is implemented using wheels, tracks, and legs; and whose payloads vary from microinstruments to large scale assemblies for construction. Robotic vehicles and their associated control systems, developed in the late 1980's as part of a proposed Mars Rover Sample Return (MRSR) mission, are described. Goals suggested at the time for such a MRSR mission included navigating for one to two years across hundreds of kilometers of Martian surface; traversing a diversity of rugged, unknown terrain; collecting and analyzing a variety of samples; and bringing back selected samples to the lander for return to Earth. Current plans (considerably more modest) which have evolved both from technological 'lessons learned' in the previous period, and modified aspirations of NASA missions are presented. Some of the demonstrated capabilities of the developed machines and the technologies which made these capabilities possible are described.

Weisbin, C. R.↗
NASA NTRS1993

Summary of Lift and Lift/Cruise Fan Powered Lift Concept Technology

A summary is presented of some of the lift and lift/cruise fan technology including fan performance, fan stall, ground effects, ingestion and thrust loss, design tradeoffs and integration, control effectiveness and several other areas related to vertical short takeoff and landing (V/STOL) aircraft conceptual design. The various subjects addressed, while not necessarily pertinent to specific short takeoff/vertical landing (STOVL) supersonic designs being considered, are of interest to the general field of lift and lift/cruise fan aircraft designs and may be of importance in the future. The various wind tunnel and static tests reviewed are: (1) the Doak VZ-4 ducted fan, (2) the 0.57 scale model of the Bell X-22 ducted fan aircraft, (3) the Avrocar, (4) the General Electric lift/cruise fan, (5) the vertical short takeoff and landing (V/STOL) lift engine configurations related to ingestion and consequent thrust loss, (6) the XV-5 and other fan-in-wing stall consideration, (7) hybrid configurations such as lift fan and lift/cruise fan or engines, and (8) the various conceptual design studies by air-frame contractors. Other design integration problems related to small and large V/STOL transport aircraft are summarized including lessons learned during more recent conceptual design studies related to a small executive V/STOL transport aircraft.

Cook, Woodrow L.↗
NASA NTRS1993

A user view of the EURECA ground segment

The European Retrievable Carrier (EURECA) was launched on 31 Jul. 1992. It is the largest ESA spacecraft ever launched, and the first one to be launched and retrieved by the NASA Space Shuttle. This paper describes the lessons learned during the first months of utilization of the EURECA ground segment from the point of view of the flight control team.

Ferri, Paolo↗
NASA NTRS1993

A review of mission planning systems

A general definition of Mission Planning is given. The definition covers the full scope of an end-to-end mission planning system. Noting the mission-specific nature of most mission planning systems, a classification of autonomous spacecraft missions is made into Observatory, Survey, multi-instrument science, and Telecommunications missions. The mission planning approach for one mission in each category is examined critically. The following missions were chosen: ISO (Infrared Space Observatory); ERS-1 (European Remote Sensing Satellite); and Eureca (European Retrievable Carrier). The paper gives a summary of lessons learned from these missions suggesting improvements in areas such as requirements analysis, testing, user interfacing, rules, and constraints handling. The paper will also examine commonalities in functions, which could constitute a basis for identification of generic mission planning support tools.

Jones, M.↗