32 research outputs found

    Sixth Aerospace Mechanisms Symposium

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    Design and development of mechanisms for spacecraft components - conference

    A systems engineering approach to disturbance minimization for spacecraft utilizing controlled structures technology

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1991.Includes bibliographical references (leaves 159-163).by Christopher Emil Eyerman.M.S

    Space Mechanisms Lessons Learned Study. Volume 2: Literature Review

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    Hundreds of satellites have been launched to date. Some have operated extremely well and others have not. In order to learn from past operating experiences, a study was conducted to determine the conditions under which space mechanisms (mechanically moving components) have previously worked or failed. The study consisted of an extensive literature review that included both government contractor reports and technical journals, communication and visits (when necessary) to the various NASA and DOD centers and their designated contractors (this included contact with project managers of current and prior NASA satellite programs as well as their industry counterparts), requests for unpublished information to NASA and industry, and a mail survey designed to acquire specific mechanism experience. The information obtained has been organized into two volumes. Volume 1 provides a summary of the lesson learned, the results of a needs analysis, responses to the mail survey, a listing of experts, a description of some available facilities, and a compilation of references. Volume 2 contains a compilation of the literature review synopsis

    Rotor Position Tracking Control for Low Speed Operation of Direct-Drive PMSM Servo System

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    In this paper, a rotor position tracking control (RPTC) strategy is proposed to effectively reduce the speed fluctuation for a direct-drive permanent magnet synchronous motor (DD-PMSM) servo system operating at low speed with different torque disturbances. In this strategy, considering the derivative relationship between the rotor position and speed, a speed command is converted to a real-time rotor position trajectory, and then a position-current two-loop control with the RPTC controller is proposed based on the internal model method to smoothly track the rotor position. In addition, the parameter design of RPTC controller from the perspectives of robust stability and anti-disturbance capability is investigated as well. Comparative simulation and experimental results demonstrate that, at low speed, the proposed RPTC strategy has a good speed performance for both periodic and non-periodic torque disturbances. Moreover, it enjoys simple implementation for not requiring the precise speed feedback and specific torque disturbance information

    High Energy Astronomy Observatory, Mission C, Phase A. Volume 2: Preliminary analyses and conceptual design

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    An analysis and conceptual design of a baseline mission and spacecraft are presented. Aspects of the HEAO-C discussed include: baseline experiments with X-ray observations of space, analysis of mission requirements, observatory design, structural analysis, thermal control, attitude sensing and control system, communication and data handling, and space shuttle launch and retrieval of HEAO-C

    Large Telescope Experiment Program /LTEP/. Volume 2 - Technical proposal Final technical report

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    Summary of large telescope development progra

    Design of an optical interferometer spacecraft

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    Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1992.Includes bibliographical references (leaves 131-134)by Andrew Marc Nisbet.M.S

    Optical technology Apollo extension system /OTES/, volume 2 Final report

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    Subsystem conceptual design for manned optical technology extension system - Apollo spacecraf

    Technology for large space systems: A bibliography with indexes (supplement 22)

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    This bibliography lists 1077 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to the researcher or manager engaged in the development of technologies related to large space systems. Subject areas include mission and program definition, design techniques, structural and thermal analysis, structural dynamics and control systems, electronics, advanced materials, assembly concepts, and propulsion
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