Dynamic modeling of a soft micro robot equipped with SMA actuator and investigating the effect of electric current and fluid velocity on its dynamic behavior

In this paper, dynamic modeling of a soft micro robot equipped with shape memory alloy (SMA) actuator is presented. Due to the structure of the soft micro robots, these robots have various applications. Since the shape memory alloys have features such that biocompatibility, high power, small dimensions and working silently, they are suitable for the micro robots. Because there is not a dynamic model for the soft robots equipped with shape memory alloy, here a dynamic model of a micro robot equipped with SMA is introduced. To this end, the motion equations of the robot and actuator’s structural equations are extracted. In dynamic modeling of the soft robot, Cosserat theory is used and Liang and Roger’s model is used for the SMA modeling. Also, modeling of free and forced convection heat transfer in the heating and cooling processes has been done. Then, the dynamic behavior of the micro robot is simulated and its electrical current effect and fluid velocity on the robot's dynamic behavior have been investigated. The simulation results show that the proposed model simulates correctly the behavior of the micro robot.