Abstract
In this brief paper, both static and dynamic behaviors of an electrostatic-actuated MEMS mirror are modeled and studied. To overcome the intrinsic pull-in problem and the dynamic disadvantages in the open-loop controlled actuation, a novel closed-loop feedback control method is proposed assuming the mirror tilt angle can be measured. First, a fixed voltage slightly higher than the pull-in voltage is applied when the mirror tilt angle is small. Then Proportional-Derivative (PD) control is used when the mirror is approaching the target position. Simulink simulation results show that this combined PD closed-loop control can overcome the pull-in problem and improve the dynamic behavior; furthermore, it can also enhance the robustness of the mirror actuation system to overcome environmental disturbances.
