+ Visit NASA.gov + Contact NASA   + Home Collection > NASA  Author > Lou, Michael C.  Author > Shih, Choon-Foo  NASA Center > Jet Propulsion Laboratory  Publication Year > 1991-2000 > 1991  Subject > S-U > Spacecraft Design, Testing And Performance  Availability Options > Online > PDF  Item/Media Type > Conference Paper  Note: Start a new navigation search by selecting a link above     Previous Record | Next Record + Back to Results   + Printer Friendly Title: System dynamic simulation of precision segmented reflector Author(s): Shih, Choon-Foo; Lou, Michael C. Abstract: A joint effort was undertaken on a Precision Segmented Reflector (PSR) Project. The missions in which the PSR is to be used will use large (up to 20 m in diameter) telescopes. The essential requirement for the telescopes is that the reflector surface of the primary mirror must be made extremely precise to allow no more than a few microns of errors and, additionally, this high surface precision must be maintained when the telescope is subjected to on-orbital mechanical and thermal disturbances. Based on the mass, size, and stability considerations, reflector surface formed by segmented, probably actively or passively controlled, composite panels are regarded as most suitable for future space based astronomical telescope applications. In addition to the design and fabrication of composite panels with a surface error of less than 3 microns RMS, PSR also develops related reflector structures, materials, control, and sensing technologies. As part of the planning effort for PSR Technology Demonstration, a system model which couples the reflector, consisting of panels, support truss and actuators, and the optical bench was assembled for dynamic simulations. Random vibration analyses using seismic data obtained from actual measurements at the test site designated for PSR Technology Demonstration are described. NASA Center: Jet Propulsion Laboratory Publication Date: Mar 1, 1991 Document Source: CASI Online Source: View PDF File Document ID: 19910013004 Accession ID: 91N22317 Publication Information: NASA. Langley Research Center, Fourth NASA Workshop on Computational Control of Flexible Aerospace Systems, Part 1, p 133-144, Number of Pages = 12 Price Code: A03 Keywords: ACTIVE CONTROL; CONTROL STABILITY; CONTROL SYSTEMS DESIGN; MIRRORS; RANDOM VIBRATION; REFLECTORS; ACTUATORS; COMPOSITE STRUCTURES; ERRORS; PANELS; SIMULATION; TELESCOPES; TRUSSES; Notes: In NASA. Langley Research Center, Fourth NASA Workshop on Computational Control of Flexible Aerospace Systems, Part 1 p 133-144 (SEE N91-22307 14-18) Accessibility: Unclassified; No Copyright; Unlimited; Publicly available; Updated/Added to NTRS: 2008-05-31 + Back to Top + Sponsored by the NASA Scientific and Technical    Information Program + 2004 Vision for Space Exploration + Freedom of Information Act + NASA Web Privacy Policy and Important Notices + NASA Disclaimers, Copyright Notice,    and Terms and Conditions of Use NASA Official: Calvin Mackey Page Curator: NASA Center for AeroSpace Information (help@sti.nasa.gov) Last Updated: July 5, 2007