MICROVIBRATION CONTROL ON A SATELLITE TRUSS STRUCTURE

摘要

Microvibration control is a topic of great interest in the space community, both for military and civilian applications. A test structure has been designed to validate active control strategies aimed at isolating an observation platform from vibrations coming from the base structure. Typical excitations are due to inertial wheels, cryogenic coolers and other disturbances. The active truss connecting the base to the observation platform is made up of six bars equipped with piezoelectric translators and force sensors. These sensor/actuator pairs -three on each bar- are located off the bar neutral line so that longitudinal and flexural actuation are possible. The first phase of the study involved control of the platform through simultaneous actuation of the three translators with a common control law. Feedback controller design had to take into account the very rich dynamics of the truss in the frequency band 0 to 3000 Hz, even though performance was required in a subset of this range, namely 20-200 Hz. These particular aspects of the problem called for robust control approaches. The design of the controller has been carried out from a simplified model of the structure, and real time implementations have been successfully achieved. Experimental results will be shown in the course of the presentation, that validate the approach for broadband feedback vibration isolation.