Reliability-based topology optimization design of a linear piezoelectric micromotor using an optimum finite element method

This article presents reliability-based topology optimization design of a linear micromotor, including multitude cantilever piezoelectric microbimorphs. This design is considered for quasi-static and linear conditions, and a relatively new computational approach called the smoothed finite element method is applied. Since microfabrication methods are used for manufacturing this type of actuator, the uncertainty variables become very important. Hence, these variables are considered as constraints during our topology optimization design process and reliability-based topology optimization is conducted. To avoid the overly-stiff behavior in finite element method modeling, the cell-based smoothed finite element method (as a branch of smoothed finite element method) has been conducted for this problem. Here, after finding the most effective random design variables using the performance measure approach and first-order reliability approximation, the topology optimization procedure is implemented in order to find an optimum piezoelectric volume fraction (as an unknown constraint for the first step) using piezoelectric material with penalization and polarization model and method of moving asymptotes optimizer. After determining problem constraints, topology optimization design is followed. This algorithm is called reliability-based design optimization using independent approach. Numerical tests show that final characters of the optimized model using cell-based smoothed finite element methods are improved compared with standard finite element methods.