The study of baseline drift in MEMS sonar buoys

MEMS sonar buoys are susceptible to motion induced by surface wave excitation, leading to signal distortion and baseline drift. To address this, a coupled motion model between the buoy and surface waves was developed using COMSOL Multiphysics 6.0, with results consistent with theoretical analysis. The output response of the MEMS buoy under vibrations from different directions was simulated, and its sensitivity to vibration direction was analyzed. A damping device comprising two disks connected by multiple elastic ropes was proposed. Transfer function analysis was used to evaluate the impact of key design parameters, revealing superior vibration isolation across frequencies compared to traditional single-disk setups. Experimental validation showed that the proposed design effectively smooths the output signal baseline, achieving an improvement of 18.55 dB at 4 Hz. This study provides a multiphysics-based method for understanding buoy–wave interactions and offers a practical solution to enhance measurement stability. The proposed damping system holds significant promise for improving MEMS sonar buoy performance in complex marine environments.