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At least 343 records · Page 19

Autonomy and automation for Space Station housekeeping and maintenance functions

The Space Station crew will be a critical resource for economical operation of science and commercial payloads. Core station housekeeping and maintenance functions should be provided in a manner that requires a minimum of crew interaction. This paper outlines a prospective functional architecture for allocation of autonomous and automated control of these functions and discusses implementation issues arising from safety of manned operations, integration test requirements, and evolution of future station capabilities.

Turner, P. R.↗

System maintenance manual for master modeling of aerodynamic surfaces by three-dimensional explicit representation

A system of computer programs has been developed to model general three-dimensional surfaces. Surfaces are modeled as sets of parametric bicubic patches. There are also capabilities to transform coordinate to compute mesh/surface intersection normals, and to format input data for a transonic potential flow analysis. A graphical display of surface models and intersection normals is available. There are additional capabilities to regulate point spacing on input curves and to compute surface intersection curves. Internal details of the implementation of this system are explained, and maintenance procedures are specified.

Gibson, A. F.↗

Cell Maintenance Systems

Living human cells require attachment to a suitable surface and special culture conditions in order to grow. These requirements are modified and amplified when cells are taken into a weightless environment. Special handling and maintenance systems are required for routine laboratory procedures conducted in the Orbiter and in the Spacelab. Methods were developed to maintain cells in special incubators designed for the Orbiter middeck, however, electrophoresis and other experiments require cells to be harvested off of the culture substrate before they can be processed or used. The cell transport assembly (CTA) was flown on STS-8, and results show that improvements are required to maintain adequate numbers of cells in this device longer than 48 hours. The life sciences middeck centrifuge probably can be used, but modifications will be required to transfer cells from the CTA and keep the cells sterile. Automated systems such as the Skylab SO-15 flight hardware and crew operated systems are being evaluated for use on the Space Shuttle, Spacelab, and Space Station research modules.

Morrison, D. R.↗

Automated crew procedure maintenance

The preparation of 30 controlled documents for each flight of the Space Shuttle involves 90 people in processing 200 or 300 changes to existing checklists, and building new procedures. A prototype system is discussed which stores and displays those precise sets of instructions, which include rationale and change history, by using readily available hardware. It provides a simple method of structuring the data in a form for easy undertanding and maintenance.

Hollingshead, P.↗

The cognitive connection: Software maintenance and documentation

With the goal of trying to understand what software maintainers do, talking aloud, video taped protocols with four expert maintainers were conducted as they were actively engaged in the process of enhancing a relatively small, interactive database program. The subjects exhibited a number of different types of information gathering strategies. Underlying these patterns of behavior, however, was the use of expectations about what should be seen in the program under examination. These expectations were generated on the basis of knowledge previously acquired as to the goals and programming plans that are typically employed in realizing interactive database programs. Thus, while the experts seemed to posses adequate programming knowledge, their actual code patches violated a basic principle of program structure. This failure by the programmers was attributed to ineffective program documentation. Suggestions for changes in the content of program documentation that should better facilitate software maintenance are presented.

Soloway, E.↗

Laser-photodetector timing station instruction and maintenance manual

A laser photodetector station is used for detecting the arrival of a projectile at a specific point along a ballistic range. The system can be employed on either an open or evacuated range, with small projectiles, and at hypervelocities. The setup procedures, maintenance, and system components are described.

Strader, E. A.↗

Managing Development and Maintenance of Software

Source Management Utility (SMU) computer program is tool to manage development and maintenance of computer software. Its purpose to control organization of configured data sets containing source, object, and load-module files. Written in PL/1 and assembler.

Rook, Gerald W.↗

Manned Mars mission health maintenance facility

The Health Maintenance Facility (HMF) requirements which enable/enhance manned Mars missions (MMMs) are addressed. It does not attempt to resolve any issues that may affect the feasibility of any given element in the HMF. Reference is made to current work being conducted in the design of the space station HMF. The HMF requirements are discussed within the context of two distinctly different scenarios: HMF as part of the Mars surface infrastructure, and HMF as part of the nine months translation from low Earth orbit to Mars orbit. Requirements for an HMF are provided, and a concept of HMF is shown.

Degioanni, Joseph C.↗

Reliability and maintenance simulation of the Hubble Space Telescope

An analytical approach is presented which was developed and implemented at MSFC specifically for the Space Telescope Program to provide comparisons of critical item failures, system downstates, on-orbit servicing versus return for ground maintenance, overall system downtime, and to obtain a measure of expected uptime for science functions.

Pizzano, F.↗

Space Assembly, Maintenance, and Servicing Study (SAMSS)

The goal is to define and establish Space Assembly, Maintenance, and Servicing (SAMS) capabilities to meet requirements for improved space systems. Consolidated requirements, hardware/tool concepts, systems analysis, related studies interaction, and schedule/milestones are outlined. This presentation is represented by charts and figures only.

Wong, Joseph↗

An assessment of clinical chemical sensing technology for potential use in space station health maintenance facility

A Health Maintenance Facility is currently under development for space station application which will provide capabilities equivalent to those found on Earth. This final report addresses the study of alternate means of diagnosis and evaluation of impaired tissue perfusion in a microgravity environment. Chemical data variables related to the dysfunction and the sensors required to measure these variables are reviewed. A technology survey outlines the ability of existing systems to meet these requirements. How the candidate sensing system was subjected to rigorous testing is explored to determine its suitability. Recommendations for follow-on activities are included that would make the commercial system more appropriate for space station applications.

Source record↗

SAMSS: An in-progress review of the Spacecraft Assembly, Maintenance, and Servicing Study

The Spacecraft Assembly, Maintenance, and Servicing Study (SAMSS) is an effort to define and verify the most cost effective approach to spacecraft servicing, as a alternative to replacement, in the 1990's and beyond. The intent of the study is to assess the servicing of satellites in all orbit regimes. Elements of a space servicing infrastructure are developed and cost estimates are generated. Readiness is assessed and proof of concept demonstrations are identified. Cryogenic fuel resupply is discussed.

Burt, William W.↗

Tutoring electronic troubleshooting in a simulated maintenance work environment

A series of intelligent tutoring systems, or intelligent maintenance simulators, is being developed based on expert and novice problem solving data. A graded series of authentic troubleshooting problems provides the curriculum, and adaptive instructional treatments foster active learning in trainees who engage in extensive fault isolation practice and thus in conditionalizing what they know. A proof of concept training study involving human tutoring was conducted as a precursor to the computer tutors to assess this integrated, problem based approach to task analysis and instruction. Statistically significant improvements in apprentice technicians' troubleshooting efficiency were achieved after approximately six hours of training.

Gott, Sherrie P.↗

The Environment for Application Software Integration and Execution (EASIE) version 1.0. Volume 4: System installation and maintenance guide

The Environment for Application Software Integration and Execution (EASIE) provides both a methodology and a set of software utility programs to ease the task of coordinating engineering design and analysis codes. This document provides necessary information for installing the EASIE software on a host computer system. The target host is a DEX VAX running VMS version 4; host dependencies are noted when appropriate. Relevant directories and individual files are identified, and compile/load/execute sequences are specified. In the case of the data management utilities, database management system (DBMS) specific features are described in an effort to assist the maintenance programmer in converting to a new DBMS. The document also describes a sample EASIE program directory structure to guide the program implementer in establishing his/her application dependent environment.

Randall, Donald P.↗

A simulation program for the analysis of on-orbit Space Station maintenance and logistics operations

This paper describes the analysis approach adopted by NASA's Space Station Maintenance Planning and Analysis (MPA) Study and focuses on the development and use of a simulation program called Simulation of Manned Space System Logistics Support (SIMSYLS) for modeling the Space Station operations environment. The basic assumptions and groundrules used in the development of SIMSYLS are presented, including its capabilities, limitations and samples of analyses performed. Finally, a proposed simulation outgrowth entitled Space Applications System Simulation (SASS) is described. SIMSYLS will constitute the foundation for SASS which will provide a full system operational RAM analysis tool for Space Station and its logistics support environment.

Furlong, Kelly L.↗

Lunar robotic maintenance module

A design for a robotic maintenance module that will assist a mobile 100-meter lunar drill is introduced. The design considers the following areas of interest: the atmospheric conditions, actuator systems, power supply, material selection, weight, cooling system and operation.

Ayres, Michael L.↗

Evolution of EVA Capabilities for Space Station Construction and Maintenance: Soviet and American Experience

The evolution of both Soviet and American Extravehicular Activity (EVA) is discussed. A qualitative review evaluates each EVA with respect to risk, criticality, complexity, and duration. Graphics summarizing increase and rate of increase in productivity emphasize related advancements in the space suits, EVA tools, and equipment technology. Specifics that demonstrated ingenuity in accomplishing unplanned activities which required man's direct manipulation of large payloads and structures are presented. Accumulated EVA successes allow an effective, flexible, recommended approach for construction and maintenance of Space Station to be given in conclusion.

Cathy D Kramer↗