Design Enhancement of Folded Beams Attachment for MEMS-Based Triaxial Accelerometer

This work presents a study through simulations of an improved MEMS-based triaxial piezoelectric accelerometer. The starting structure of the sensor consists of a seismic mass suspended by four folded beams. Specifically, the beam suspension is placed on both sides of the mass in alignment with the mass’s edges. To evaluate the multiaxial sensitivity, detection electrodes are distributed at the ends of the folded beams. First, the sensor was studied using the finite element method (FEM) to validate the mechanical and electrical behavior in the literature. Next, a geometric optimization, to improve the performance of the existing structure, is carried out by incorporating trapezoidal with corners (TWC)-based beams to obtain maximum stress and therefore higher sensitivity. The results showed that the sensitivity of the modified design was significantly increased by 40%, 42.4, and 50.4% along the x-, y-, and z-axes, respectively, compared to the folded beam-based structure.