Arc-heating actuated active-morphing insect robots

Abstract

In nature, insects can swiftly move and actively morph to adapt to complex and varied conditions. However, replicating this capability in insect-scale robots requires sophisticated structural designs, which are difficult to achieve at such a small scale without fundamental hardware innovations. This work proposes a coupling mechanism between actuation and morphing by combining an arc-heating actuator and shape memory alloy wires, presenting a fast insect-scale robot (83.4 body lengths per second) capable of active morphing and self-recovery. The arc-heating actuator is designed to provide the kinetic energy and the thermal energy essential for deforming the wires. The robot can compress its body thickness to traverse through a gap of 70% its height smoothly within 2.2 seconds and is amphibious. Furthermore, after enduring pressure 5 million times its weight, the robot is flattened, but fully recovers its original size and performance in just a few seconds. Replicating the swift movement and active morphing of insects in small-scale robots is challenging. The authors developed an insect-scale robot using an arc-heating actuator and shape memory alloy wires, achieving rapid movement, shape morphing, and self-recovery.