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At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Assembling, maintaining and servicing Space Station

The assembly, maintenance, and servicing of the Space Station and its facilities are discussed. The tools and facilities required for the assembly, maintenance, and servicing of the Station are described; the ground and transportation infrastructures needed for the Space Station are examined. The roles of automation and robotics in reducing the EVAs of the crew, minimizing disturbances to the Space Station environment, and enhancing user friendliness are investigated. Servicing/maintenance tasks are categorized based on: (1) urgency, (2) location of servicing/maintenance, (3) environmental control, (4) dexterity, (5) transportation, (6) crew interactions, (7) equipment interactions, and (8) Space Station servicing architecture. An example of a servicing mission by the Space Station for the Hubble Space Telescope is presented.

Doetsch, K. H.↗
NASA NTRS1988

Dynamics and control characteristics of a reference Space Station configuration

This paper describes the structural dynamic characteristics of a NASA reference space station configuration as defined in the November 1987 Space Station Program - Systems Engineering and Integration Engineering Data Book. The modes and frequencies of the station below 2.0 Hz were obtained and selected results along with rigid body properties are presented. A three-axis attitude control system using control moment gyros responding to attitude and attitude rate signals is used to regulate the orientation of the station. The stability of the control system with non-collocated sensors is investigated for both compensated and uncompensated control signals. Results from a closed-loop simulation of a commanded attitude change about three axes, and from a closed-loop simulation of the response of the station to an externally applied unit force impulse at the docking port are presented. These simulation results are used to evaluate the possible degree of control/structures interaction which could occur during normal operation of the station.

Sutter, Thomas R.↗
NASA NTRS1987

An overview of the program to place advanced automation and robotics on the Space Station

The preliminary design phase of the Space Station has uncovered a large number of potential uses of automation and robotics, most of which deal with the assembly and operation of the Station. If NASA were to vigorously push automation and robotics concepts in the design, the Station crew would probably be free to spend a substantial portion of time on payload activities. However, at this point NASA has taken a conservative attitude toward automation and robotics. For example, the belief is that robotics should evolve through telerobotics and that uses of artificial intelligence should be initially used in an advisory capacity. This conservativeness is in part due to the new and untested nature of automation and robotics; but, it is also due to emphases plased on designing the Station to the so-called upfront cost without thoroughly understanding the life cycle cost. Presumably automation and robotics has a tendency to increase the initial cost of the Space Station but could substantially reduce the life cycle cost. To insure that NASA will include some form of robotic capability, Congress directed to set aside funding. While this stimulates the development of robotics, it does not necessarily stimulate uses of artificial intelligence. However, since the initial development costs of some forms of artificial intelligence, such as expert systems, are in general lower than they are for robotics one is likely to see several expert systems being used on the Station.

Heydorn, Richard P.↗
NASA NTRS1988

Space station functional relationships analysis

A systems engineering process is developed to assist Space Station designers to understand the underlying operational system of the facility so that it can be physically arranged and configured to support crew productivity. The study analyzes the operational system proposed for the Space Station in terms of mission functions, crew activities, and functional relationships in order to develop a quantitative model for evaluation of interior layouts, configuration, and traffic analysis for any Station configuration. Development of the model involved identification of crew functions, required support equipment, criteria of assessing functional relationships, and tools for analyzing functional relationship matrices, as well as analyses of crew transition frequency, sequential dependencies, support equipment requirements, potential for noise interference, need for privacy, and overall compatability of functions. The model can be used for analyzing crew functions for the Initial Operating Capability of the Station and for detecting relationships among these functions. Note: This process (FRA) was used during Phase B design studies to test optional layouts of the Space Station habitat module. The process is now being automated as a computer model for use in layout testing of the Space Station laboratory modules during Phase C.

Tullis, Thomas S.↗
NASA NTRS1989

Evolutionary growth for Space Station Freedom electrical power system

Over an operational lifetime of at least 30 yr, Space Station Freedom will encounter increased space station user requirements and advancing technologies. The space station electrical power system is designed with the flexibility to accommodate these emerging technologies and expert systems and is being designed with the necessary software hooks and hardware scars to accommodate increased growth demand. The electrical power system is planned to grow from the initial 75 kW up to 300 kW. The Phase 1 station will utilize photovoltaic arrays to produce the electrical power; however, for growth to 300 kW, solar dynamic power modules will be utilized. Pairs of 25 kW solar dynamic power modules will be added to the station to reach the power growth level. The addition of solar dynamic power in the growth phase places constraints in the initial space station systems such as guidance navigation and control, external thermal, truss structural stiffness, computational capabilities and storage which must be planned-in in order to facilitate the addition of the solar dynamic modules.

Marshall, Matthew F.↗
NASA NTRS1988

Space Station payload accommodations

Accommodating a multitude of diverse payloads on the Space Station base and its platforms requires an early definition of payload candidates to assure an adequate assessment of payload requirements. The task of interpreting the payload requirements, translating them into Station design requirements, and developing the processes and procedures to accommodate and integrate the user onto the Station is the function of the NASA Space Station Program Office Utilization and Operations Group. This paper describes the Space Station assembly sequence, time-phased payload accommodations, and the unique research environment provided by the Space Station.

Hemmerdinger, Louis↗
NASA NTRS1988

An examination of automation and robotics in the context of Space Station operations

A NASA-sponsored review of Space Station automation and robotics (A&R) applications from an operations and utilization perspective is presented. The goals of the A&R panel and this report are to identify major suggestions for advanced A&R operations application in Space Station as well as key technologies that have emerged or gained prominence since the completion of previous reports; to review and incorporate the range of possible Space Station A&R applications into a framework for evaluation of A&R opportunities; and to propose incentives for the government, work packages, and subcontractors to more aggressively identify, evaluate, and incorporate advanced A&R in Space Station Operations. The suggestions for A&R focused on narrow objectives using a conservative approach tuned to Space Station at IOC and limiting the Station's growth capabilities. A more aggressive stance is to identify functional needs over the Program's life, exploit and leverage available technology, and develop the key advanced technologies permitting effective use of A&R. The challenge is to systematically identify candidate functions to be automated, provide ways to create solutions resulting in savings or increased capabilities, and offer incentives that will promote the automation.

Criswell, David R.↗
NASA NTRS1990

Sensitivity study of Space Station Freedom operations cost and selected user resources

The results of sensitivity studies performed to estimate probable ranges for four key Space Station parameters using the Space Station Freedom's Model for Estimating Space Station Operations Cost (MESSOC) are discussed. The variables examined are grouped into five main categories: logistics, crew, design, space transportation system, and training. The modification of these variables implies programmatic decisions in areas such as orbital replacement unit (ORU) design, investment in repair capabilities, and crew operations policies. The model utilizes a wide range of algorithms and an extensive trial logistics data base to represent Space Station operations. The trial logistics data base consists largely of a collection of the ORUs that comprise the mature station, and their characteristics based on current engineering understanding of the Space Station. A nondimensional approach is used to examine the relative importance of variables on parameters.

Accola, Anne↗
NASA NTRS1989

Evolutionary growth for Space Station Freedom electrical power system

Over an operational lifetime of at least 30 yr, Space Station Freedom will encounter increased Space Station user requirements and advancing technologies. The Space Station electrical power system is designed with the flexibility to accommodate these emerging technologies and expert systems and is being designed with the necessary software hooks and hardware scars to accommodate increased growth demand. The electrical power system is planned to grow from the initial 75 kW up to 300 kW. The Phase 1 station will utilize photovoltaic arrays to produce the electrical power; however, for growth to 300 kW, solar dynamic power modules will be utilized. Pairs of 25 kW solar dynamic power modules will be added to the station to reach the power growth level. The addition of solar dynamic power in the growth phase places constraints in the initial Space Station systems such as guidance, navigation, and control, external thermal, truss structural stiffness, computational capabilities and storage, which must be planned-in, in order to facilitate the addition of the solar dynamic modules.

Marshall, Matthew Fisk↗
NASA NTRS1989

Space station

The history of American space flight indicates that a space station is the next logical step in the scientific pursuit of greater knowledge of the universe. The Space Station and its complement of space vehicles, developed by NASA, will add new dimensions to an already extensive space program in the United States. The Space Station offers extraordinary benefits for a comparatively modest investment (currently estimated at one-ninth the cost of the Apollo Program). The station will provide a permanent multipurpose facility in orbit necessary for the expansion of space science and technology. It will enable significant advancements in life sciences research, satellite communications, astronomy, and materials processing. Eventually, the station will function in support of the commercialization and industrialization of space. Also, as a prerequisite to manned interplanetary exploration, the long-duration space flights typical of Space Station missions will provide the essential life sciences research to allow progressively longer human staytime in space.

Stewart, Donald F.↗
NASA NTRS1990

Multiple manipulator control from orbiter for Space Station assembly

This paper discusses the assembly process of the Space Station Freedom. It is shown that the assembly of the Space Station will require 29 flights of the Space Shuttle Orbiter: six shuttle flights during the initial assembly stage when the Space Station will not have sufficient life-support capability; seven more flights before the Station will support human occupation independent of the presence of the Space Shuttle; and 16 more flights for achieving full operational capability. The shuttle systems to be used in the Space Station assembly are described together with the results of simulation and analyses. Special attention is given to the Space Shuttle Remote Manipulator System which will be available on all Shuttle flights to support the Space Station assembly.

Price, Charles R.↗
NASA NTRS1988

Space station tracking requirements feasibility study, volume 2

The objective of this feasibility study is to determine analytically the accuracies of various sensors being considered as candidates for Space Station use. Specifically, the studies were performed whether or not the candidate sensors are capable of providing the required accuracy, or if alternate sensor approaches should be investigated. Other topics related to operation in the Space Station environment were considered as directed by NASA-JSC. The following topics are addressed: (1) Space Station GPS; (2) Space Station Radar; (3) Docking Sensors; (4) Space Station Link Analysis; (5) Antenna Switching, Power Control, and AGC Functions for Multiple Access; (6) Multichannel Modems; (7) FTS/EVA Emergency Shutdown; (8) Space Station Information Systems Coding; (9) Wanderer Study; and (10) Optical Communications System Analysis. Brief overviews of the abovementioned topics are given. Wherever applicable, the appropriate appendices provide detailed technical analysis. The report is presented in two volumes. This is Volume 2, containing Appendices K through U.

Udalov, Sergei↗
NASA NTRS1988

Space station tracking requirements feasibility study, volume 1

The objective of this feasibility study is to determine analytically the accuracies of various sensors being considered as candidates for Space Station use. Specifically, the studies were performed whether or not the candidate sensors are capable of providing the required accuracy, or if alternate sensor approaches be investigated. Other topics related to operation in the Space Station environment were considered as directed by NASA-JCS. The following topics are addressed: (1) Space Station GPS; (2) Space Station Radar; (3) Docking Sensors; (4) Space Station Link Analysis; (5) Antenna Switching, Power Control, and AGC Functions for Multiple Access; (6) Multichannel Modems; (7) FTS/EVA Emergency Shutdown; (8) Space Station Information Systems Coding; (9) Wanderer Study; and (10) Optical Communications System Analysis. Brief overviews of the abovementioned topics are given. Wherever applicable, the appropriate appendices provide detailed technical analysis. The report is presented in two volumes. This is Volume 1, containing the main body and Appendices A through J.

Udalov, Sergei↗
NASA NTRS1992

Space Station Freedom Utilization Conference

The topics addressed in Space Station Freedom Utilization Conference are: (1) space station freedom overview and research capabilities; (2) space station freedom research plans and opportunities; (3) life sciences research on space station freedom; (4) technology research on space station freedom; (5) microgravity research and biotechnology on space station freedom; and (6) closing plenary.

Source record↗
NASA NTRS1992

Space Station Freedom research capabilities

NASA's plan for enhancing space-based research capabilities begins with extended-duration Space Shuttle missions that will double the research capability currently provided by Spacelab and culminate in Space Station Freedom. The 14-day USML 1 mission flown on the Space Shuttle in June 1992 was a space station precursor mission, dedicated to microgravity and life science research. Freedom will be a permanent space-based research facility, providing a working environment nearly free of buoyancy-driven convection, sedimentation, and hydrostatic pressure and featuring access to the ultra-high vacuum of space (for external payloads). In its crew-tended phase, Space Station Freedom will provide 40 times Spacelab's capability, and in its permanently occupied phase, Freedom will provide 110 times Spacelab's capability. (The Russian space station, Mir, offers 26 times Spacelab's capabilities.) According to NASA's current schedule, the first launch of a space station element will take place in November 1995, with permanently occupied capability planned for September 1999. This year, NASA will conduct space station critical design reviews (CDR's). Work package design reviews will take place from February to April 1993, followed by a systems CDR.

Moorehead, Robert↗
NASA NTRS1985

Interaction between the space transportation systems and the Space Station architecture and operations and technology requirements

This study, limited to the interaction between the Space Station and an orbital transfer vehicle, illustrates the need to include the space transportation system and the station in a synergistic analysis to determine an overall operationally efficient system that takes full advantage of the potential for the exploration and exploitation of space. Included are examples of the effects of the mission model on the selection of a possible orbit transfer vehicle design and processing procedures at the station; safe, timely, and flexible transfer vehicle trajectories from GEO to the station; mechanical assists on the station for vehicle arrivals and departures that reduce the risk of contamination and collision; and a discussion of the need for efficient procedures for vehicle maintenance and processing at the station.

Eide, Donald G.↗
NASA NTRS1990

Space vehicle deployment from Space Station

When launching a spacecraft from Earth parking orbit to deep space, it is highly desirable to have the hyperbolic excess velocity vector (v-infinity) contained in the parking orbit plane. Ground launches can force the parking orbit plane to contain the v-infinity vector by using launch azimuth and lift-off time as independent variables. When launching from the Space Station, a new set of variables comes into play. The Space Station orbit is of fixed inclination but precessing due to the Earth's oblateness. Its plane will seldom (and may never) contain the desired v-infinity vector. Consequently, the departure strategy will usually require multiple burns and include a plane change. Also, the concept of 'launch window' will be somewhat different from Earth surface launches. An analysis of the deployment of interplanetary spacecraft from the Space Station is described, with emphasis on the effect of the trajectory characteristics on station operations. Several planetary mission types are analyzed, including manned Mars missions and unmanned high declination departures. The constraint of Space Station orbit nodal position is quantified and the operational implications for Space Station reboost strategy are examined.

Henry, Paul K.↗
NASA NTRS1993

Using computer graphics to design Space Station Freedom viewing

Viewing requirements were identified early in the Space Station Freedom program for both direct viewing via windows and indirect viewing via cameras and closed-circuit television (CCTV). These requirements reside in NASA Program Definition and Requirements Document (PDRD), Section 3: Space Station Systems Requirements. Currently, analyses are addressing the feasibility of direct and indirect viewing. The goal of these analyses is to determine the optimum locations for the windows, cameras, and CCTV's in order to meet established requirements, to adequately support space station assembly, and to operate on-board equipment. PLAID, a three-dimensional computer graphics program developed at NASA JSC, was selected for use as the major tool in these analyses. PLAID provides the capability to simulate the assembly of the station as well as to examine operations as the station evolves. This program has been used successfully as a tool to analyze general viewing conditions for many Space Shuttle elements and can be used for virtually all Space Station components. Additionally, PLAID provides the ability to integrate an anthropometric scale-modeled human (representing a crew member) with interior and exterior architecture.

Goldsberry, Betty S.↗