Robust Output Feedback Control of an Electrostatic Micro-Actuator

Due to compact layout, manufacturing tolerance, modeling errors, and environmental changes, micro-electromechanical systems (MEMS) are subjected to parasitics and parametric variations. In order to better guarantee their stability and a certain level of performance, one must take into account these factors in the design of MEMS control systems. This work presents a robust output control scheme for a parallel-plate electrostatic micro-actuator in the presence of these uncertainties. The construction of the control law is based on a combination of input-to-state stability (ISS) and robust backstepping. The stability and the performance of the system are demonstrated through both stability analysis and numerical simulation.