AAS 95-337

Parametric Excitation of Two-Rotor Gyrostats with Damping

C. D. Hall, Air Force Institute of Technology, Wright-Patterson AFB, OH

Abstract

In 1974, Scher and Farrenkopf proposed a pulsing procedure to enable a spacecraft to "escape" from a trap state. Here we study this problem with one of the rotors viscously damped and the other parametrically excited by a periodic torque. The spacecraft is intended to operate with rotor 1, denoted R1, having a specified angular momentum, and R2, subject to a viscous torque, in an all-spun condition. Normally this state is asymptotically stable. It is possible that a different asymptotically stable state exists, with R1 having the same angular momentum. Periodic excitation of R1 leads to "escape."