Influence of Nonlinear Effects Induced by Mode Coupling on Vibration Trajectories of MEMS Micromirrors

Detection of the vibration trajectories of MEMS micromirrors is crucial for ensuring their application performance. This study investigates key factors influencing micromirror vibration trajectories. When actuated by a square-wave signal containing high-frequency components, micromirrors exhibit mode coupling vibrations. By incorporating a mode coupling mechanism, this paper establishes a comprehensive vibration trajectory model for micromirrors. Numerical simulations were performed to obtain trajectory solutions. Both the experimental and simulation results demonstrate that the mode coupling leads to deviations between the actual trajectory and the expected sinusoidal pattern. These deviations compromise the accuracy of trajectory prediction systems, which typically assume that the trajectory follows a sinusoidal pattern. To mitigate the deviations caused by mode coupling, this study proposes structural parameter optimization during the micromirror design process.