3460. Using a Two-Plane Spin Balance Instrument to Balance a Satellite Rotor About Its Own Bearings

Paper

Abstract

This paper addresses the problem of statically and dynamically balancing a satellite, mounted antenna rotor supported on its own bearings, and driven by a motor in the satellite body. The satellite body is considered a stationary platform, (stator) for this procedure and is not part of the balancing problem. The antenna rotor is isolated and balanced independently while spinning on its own bearings. In order to measure the unbalance, a method is developed to utilize a two-plane vertical axis spin balance machine. Rather than using the gas bearing rotor of the measuring instrument and spinning the entire satellite, the satellite body (stator) is attached to the balancing machine table, which is held stationary, and the satellite ‘rotor’ is spun on its own bearings. Forces due to the unbalance are measured by the Spin Balance Machine force transducers. The method is compared to a similar procedure using a single plane spin balancer and to methods using ‘work reversal’ methods to balance the rotor by spinning the entire satellite. The accuracy of this procedure is compared to the basic balance capability of the spin balance instrument when used in the conventional manner.