Predicting the launch and on-orbit performance of a peripheral driven filter wheel for geosynchronous satellite remote sensors.

To image optical information in different spectral bands, remote sensors for Earth observation require an active filter-wheel drive mechanism for time-shared switching of the optical path. This paper presents the details of a modeling and testing methodology developed to predict the launch and in-orbit performance of such a filter wheel. The present filter-wheel drive mechanism was designed to achieve a highly precise and stable cut-in and cut-out optical path by means of a large-diameter angular-contact ball bearing driven by a stepper motor. A numerical model is used to analyze the structural dynamic characteristics of the system; mechanical experiments comprising modal, scanning, and microvibration tests are performed to evaluate the launch and in-orbit stability performance; and accelerated life testing of the solid-lubricated bearing is performed to predict its reliability under accelerated conditions. The results indicate that the filter-wheel system has guaranteed structural safety and the required long lifetime. This type of peripheral driven filter wheel with large thin-walled bearings provides a new method for use with large-aperture satellite cameras in space applications.