Simulation of Topology Optimized Electrothermal Microgrippers

In this work, electrothermal microgrippers designed using topology optimization are modeled. The microgrippers are composed of two 5 μm-thick polysilicon actuators facing each other. The gap between the actuators are 2 μm in the initial state and the microgrippers are able to both fully close and further open this gap. The operation principle of the actuators is quite similar to that of a parallelbeam electrothermal actuator and relies on resistive heating by passing a current through the structure. COMSOL MEMS Module is used in order to model the temperature distribution, endeffector displacement and stiffness of both topology optimized and conventional parallelbeam actuators. End-effector displacement vs. bias voltage curves for both modes, i.e. open and close, of the microgrippers obtained through finite element analysis fit almost perfectly to the experimental data.