Accession Number : AD0769288

Title :   Seismic Angular Motion Sensor,

Corporate Author : FRANK J SEILER RESEARCH LAB UNITED STATES AIR FORCE ACADEMY CO

Personal Author(s) : Okubo, Shigeo

Report Date : AUG 1973

Pagination or Media Count : 13

Abstract : The design, fabrication and evaluation of a fused silica, balanced rotor, angular motion sensor which is insensitive to linear accelerations is described. A mathematical model was developed which defines the physical parameters that could be controlled during assembly and test. The design parameters include rotor moment of inertia, torsional spring constant, and magnetic damping. An independent optical pickoff system was developed using a solid state light source and two matched photo cell detectors. Extensive testing was accomplished on the subassemblies as well as the completed sensor. Test results indicate a performance sensitivity of about 0.01 arc second with a linear range of nearly two degrees. Comparison tests between two prototype sensors indicate an excellent response to low level angular inputs in the .1 to 100 Hz frequency region. This pilot development effort of an angular motion sensor indicates that an extremely sensitive device can be fabricated from quartz which will provide broadband measurements for a wide range of critical applications. (Author)

Descriptors :   *DETECTORS, *INERTIAL GUIDANCE, EXPERIMENTAL DESIGN, BALANCE, QUARTZ, ELECTROOPTICS, ROTORS, ORIENTATION(DIRECTION), TORSION, MATHEMATICAL MODELS.

Subject Categories : Seismic Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE