A Nitinol Actuated Worm-Inspired Robot Capable of Forward Motion, Turning, and Climbing Obstacles

Abstract

This thesis introduces a new worm-inspired robot made of a pre-fabricated mesh and nitinol shape memory alloy springs.The unique arrangement of actuators enables the robot to move forward, turn left and right, lift its front segments into the air, and surmount an obstacle 14% of the robot's diameter.Multiple iterations resulted in a prototype capable of moving forward at a speed of 0.88cm/min.While testing the robot over multiple days, a significant deterioration in performance was observed.The nitinol actuators were identified as the likely cause of the degradation, after considering other potential causes.To validate or disprove this hypothesis, preliminary experiments on the effects of cyclic thermomechanical loading of the nitinol springs were conducted.The preliminary results suggest inadequate cooling time between cycles leads to a shifting of the set-point of the nitinol spring, even if the temperature is below the transition temperature of the nitinol.