Abstract: A carriage is moved along a track by a motor connected in a first control loop to a carriage position sensor. The carriage carries a chassis which is coupled to it by a flexible linkage. The chassis carries an accelerometer connected by a second control loop independent of the first control loop to a linear actuator acting on the chassis and bearing on the carriage. The chassis carries a primary mirror fastened to it and a secondary mirror coupled to it by a piezo-electric actuator controlled via a third control loop by an optical path difference OPD error signal generated in the recombination station that includes the interferometer. The third control loop is desaturated by the first or second control loop, preferably by the second control loop. The preferably stellar interferometer may be on board a spacecraft.

Abstract: A carriage moves on a track and carries, through a flexible linkage, a chassis to which is fixed a payload including an optical element. A linear actuator controls the linkage so as to correct imperfections in displacement of the payload. A piezo-electric accelerometer delivers a filtered signal to control the linear actuator so as to eliminate the effect on the payload of vibration of the carriage. There are two independent control loops, one for controlling the carriage and the other for controlling the chassis. The device is applicable to controlling the mobile part of an optical delay line or of a telescope in a stellar interferometer.