Research on Super-twisting Sliding Mode Control Based on Disturbance Observer

In this paper, a Super-twisting sliding mode control strategy on account of a nonlinear disturbance observer is proposed to solve the problem of disturbance suppression in the beam scanning process of MEMS micromirrors, in response to the degradation of the scanning precision of MEMS micromirrors due to external perturbation in the beam scanning process. The working mechanism of MEMS micromirror beam scanning is analyzed, the system model of MEMS micromirror is constructed, and the NDOB-Super-twisting controller is designed. The step response test, robustness test, and perturbation suppression analysis simulation are carried out. The results show that NDOB-Super-twisting controller has a 56.25% improvement in regulation time, no overshooting, and about 60% improvement in steady state error compared to the PID controller.