Research on Electrothermal Actuator Applied in MEMS Safety System

Abstract:
With the development and application of MEMS technology, MEMS fuze is proposed as a new concept fuze. The MEMS fuze safety system is produced to adapt to the development trend of weapon intelligence, precision, and miniaturization. As one of the key components of the MEMS fuze safety system, MEMS actuators are used in the actuators to release insurance. Focusing on the V-shaped electrothermal actuator made from polysilicon, a multi-physics coupling model with the interaction among the electric field, thermal field, and structure field was first established. Then, multi-physics coupling simulation analysis was conducted on the model using COMSOL Multiphysics, so as to obtain the steady-state characteristic results of the V-shaped electrothermal actuator. The results show that the temperature field, stress field, and displacement field are greatly affected by the electrical conductivity of polysilicon. Moreover, the inclination angle and group number of the V-shaped beam have varied influence on the output displacement. Furthermore, the thermal deformation of the V-shaped beam was theoretically analyzed and calculated to obtain the equations for solving output displacement, axial stress, and output force of the V-shaped beam. The findings can serve as a theoretic basis for optimizing the design of the electrothermal actuator in a micro-electromechanical system (MEMS).