Nonlinear control for a MEMS hard-magnetic micromirror by using backstepping sliding mode method

A backstepping sliding mode controller, which combines both backstepping control and sliding mode technique, is introduced to control the deflection trajectory of the MEMS magnetic mirror. First, mathematical model of the MEMS magnetic mirror is presented. Then, a backstepping sliding mode control (BSMC) approach is proposed to improve the performance of the MEMS based mirror. With the backstepping sliding mode controller, the experimental illustration for the magnetic mirror is conducted using a field programmable gate array (FPGA) based digital implementation platform. The result shows that the proposed control approach admits good transient control performance and robustness to uncertainties.