Shape and topology optimization for tailoring stress in a local region to enhance performance of piezoresistive sensors

Based on the analysis of a typical configuration of piezoresistive sensors, the intensity and uniformity of stress in piezoresistive elements are identified as the parameters that affect the performance of a sensor. To enhance the performance, a shape and topology optimization problem is formulated to ensure the stress is high and uniform in a local region where the piezoresistive elements are placed. The optimization problem is solved via the level set based method. To compute stress accurately, artificial weak material conventionally used to mimic void is avoided in the finite element analysis. Numerical examples in two dimensions are investigated.