Systematic design of micro actuators using topology optimization

Systematic design methods for MicroElectroMechanical Systems (MEMS) have been lacking and typical design procedures encompass trial and error approaches. This paper discusses the application of the topology optimization method as a systematic tool for MEMS design. The topology optimization method distributes one or more passive or active materials in a design domain, such that some output performance is optimized. Here, the method is applied to the design of thermal or electrothermal micro actuators where the output work performed on a workpiece of given stiffness is to be maximized. It is shown that actuators with either large output displacement or large output force can be designed by specifying low or high stiffness of the workpiece, respectively. The optimal topologies are strongly dependent on the stiffness of the workpiece as well.