Determination of Crosstalk in a Dual-axis Piezoelectric MEMS Mirror and Suppression with Feedforward Algorithms

The dual-axis micro-electro-mechanical system (MEMS) mirror has the characteristics of miniaturization, high speed and low power consumption, and is the core component of the miniaturized laser scanning and tracking system. This paper focuses on the crosstalk of dual-axis MEMS mirrors and its impact on control, so as to improve the control accuracy of laser scanning. Firstly, the comparison experiments between the conventional structure and the mechanically decoupled structure reveal that the dual-axis crosstalk is a result of mechanical coupling. This phenomenon is influenced by the frequency of driving signal and the difference in resonant frequency between the two axes. Then, the SIMULINK crosstalk model is established to explain the crosstalk effect well. Secondly, the two-step feedforward control algorithm is designed to suppress the resonance effect of the MEMS mirror, so that the crosstalk value is reduced from 28.89% to less than 2%, and the stabilization time is shortened from 2.02 s to 0.5 ms. Finally, the impact of crosstalk effect on laser two-dimensional vector scanning is studied. The feedforward algorithm improves the control accuracy from 0.096 mrad to 0.012 mrad and the scanning frame rate from 0.2 Hz to 3.8 Hz. This paper studies the crosstalk model of piezoelectric MEMS mirrors and its impact on scanning control in detail for the first time, which is important to the structure design and control algorithm of MEMS mirrors for the improvement of the control performance of MEMS mirrors.