Despite the high linearity of Al(Sc)N as piezoelectric actuator material, quasi-static MEMS mirrors show exemplary differences due to intrinsic stress. To control the static and dynamic behavior of the mirror, an electronic control system may be used. Rapid control prototyping (RCP) can be a helpful tool for developing generic or application-specific control schemes. This paper provides a practical introduction to the RCP approach and demonstrates it in practice with a gimbal-less bi-axial micro mirror. The application example is a long-range LIDAR system with optical positioning tolerance <0.1 degree and <400 µs point-to-point transition rate. An open loop control is implemented with a digital filter (finite-duration impulse response, FIR), using standard functions from MATLAB®/Simulink® to generate a random signal, a model of the mirror and a Gaussian filter. The response to the filtered input signal is simulated before running the control scheme on the RCP system. The modeling process relies on automatic code generation to program the RCP target system or other supported platforms.
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