Comparison of high performance hybrid variable reluctance fast steering mirrors

Abstract

Actuated mirrors are a key element in free-space optical communications. This paper compares the two high performance, commercially available actuators with a hybrid variable reluctance drive principle. They feature a mechanical range of up to 3degrees and achieve closed-loop bandwidths of more than 1kHz in combination with eddy-current sensors. It is shown, that the choice of driver is closely linked to their achievable dynamics. In particular, the performance in the application area of optical communication on satellites is analyzed. Therefore, in addition to the dynamic properties, the integration, their power consumption and suppression of vibrations is also being considered. To ensure comparability, a parameter tuning algorithm is used. The breadboard utilizes the same control software and hardware for both devices. The FSM20B shows better passive rejection against external vibrations, a lower average power consumption, and allows the exchange of its angular sensors. The FSM3000 achieves a better steady-state jitter, features a larger operating range and is more compact in size with precalibrated, internal sensors.