Water-jet Propelled Squid-Inspired Soft Robot Driven by Pneumatic Bistable Device

Based on the snap-through principle of the bistable structure, a water-jet propelled squid-inspired soft robot is designed. Firstly, a bistable driving device is manufactured, which can jump as the gas periodically switches on and off, to drive a reciprocating motion of the paddle film and change the internal volume of the prototype. Secondly, the prototype can spray water quickly and absorb water slowly by adjusting the driving frequency of the bistable device, and thus a momentum difference is formed to push the prototype forward. The change law of the propulsive force generated by the jump of the bistable driving device is concluded through experiments, which is applied to the drive of squid-inspired robot. Finally, the kinematic characteristics of the snap-through process of the bistable device are analyzed by experiments, and corresponding mechanical model is established. The bending performance of the driving device is simulated and analyzed by the ABAQUS simulation software to verify its bending performance. Research results show that the prototype can reach a speed of 8.7 cm/s (0.58 body length per second) driven by the bistable device, demonstrates a certain load capacity, and exhibits excellent swimming performance.