A Deformable Robot Based on Shape Memory Alloy and Phase Change Metal

The deformability of robots is important in certain task scenarios. Although phase change metals have become promising materials for deformable robots, pure phase change metal-based soft robots cannot recover their original shape after large deformations. To address this critical issue, this paper presents a deformable robot system inspired by the biological “skeleton-muscle” paradigm, which integrates shape memory alloy (SMA) skeletons and magnetic liquid metal actuation. The robot adopts a silicone elastomer shell to constitute the main structure of the robot body, while the SMA serves as the “skeleton” for the phase change metal and is embedded within the shell to provide the recovery capability via SME effect. The phase change metal fills in the shell and is driven magnetically as the flexible “muscle” for the robot to pass through the apertures/slits in its liquid phase, and for the locomotion in its solid phase. A prototype was fabricated and experimentally validated, demonstrating the robot's effective locomotion and passage capability through different slits/apertures, as well as successful recovery performance. This work provides a novel design strategy for deformable robots by combining SMA and phase change metal, expanding the environmental adaptability of deformable robotic systems.