System Identification and Control of Fast Steering Mirror Based on Voice Coil Actuators

Abstract

Fast steering mirror (FSM) is one of the key devices in the light detection and ranging (LIDAR) system and higher resolution and broader operating bandwidth are necessary. In this paper, we present a FSM based on the voice coil actuators (VCA), with a large scanning angle, although, the scanning linearity and bandwidth of the FSM are limited by the presence of mechanical resonance. A mathematical model is proposed to investigate the dynamic behavior of the FSM and based on this system model, a closed-loop controller is introduced to reject the mechanical resonances of the FSM. With the proposed controller, the non-linearity of 50Hz is reduces from 14.58% to 2.13% and the bandwidth enhances from 1244.1rad/s to 2073.5rad/s. The testing result shows that the performance of the FSM is greatly improved.