Designing Novel MEMS Cantilevers for Marine Sensing Robots Using COMSOL Modeling and Different Piezoelectric Materials

The present work presents an innovative marine sensing robotics device based on piezoelectric cantilever-integrated micro-electro-mechanical systems (MEMS) modeled on approach of fish lateral lines. The device comprises 12 cantilevers of different sizes and shapes in a cross-shaped configuration, embedded between molybdenum (Mo) as electrodes in a piezoelectric thin film (PbTiO3, GaPO4). It has the advantage of directional response due to the unique design of the circular cantilevers. In COMSOL software, we designed, modeled, and simulated a piezoelectric device based on a comparative study of these piezoelectric materials. Simulations were performed on cantilever microstructures ranging in length from 100 um to 500 um. The results show that Lead Titanate (PbTiO3) performs best with these materials. The maximum potential voltage was 4.9 mV using the PbTiO3 material cantilever with 37 um displacement. To investigate the first resonance frequency mode and displacement measurements, a Laser Doppler Vibrometer was used, and good agreement between simulations and experimental results was achieved. Its performance and compactness make us envision its employment in underwater acoustics for monitoring marine cetaceans and ultrasound communications. In conclusion, MEMS piezoelectric transducers can be used as hydrophones to sense both the amplitude and directionality of underwater acoustics pulses.