Reprogrammable Untethered Actuator For Soft Bio-Inspired Robots

The use of active materials for the actuators in soft robots allows for safe interactions and adaptable locomotion. However, stimulating the behavior of soft robots as well as reprogramming them and implementing reversible control in them remains a challenge. Herein, a method for fabricating soft, bio-inspired, untethered, infrared-driven actuators that exhibit reversible and reprogrammable behaviors is proposed. By exploiting the mismatch in the infrared-driven thermomechanical responses of the two active materials constituting the bilayered soft actuator, reversible actuation can be realized. More importantly, the shape of robots based on this actuator can be reprogrammed such that they exhibit bio-inspired locomotion specific to the environment. For instance, a soft robot based on the actuator can be made to exhibit several bio-inspired functions, such as crawling, rolling, and object manipulation, in a complex environment. Furthermore, reversible and reprogrammable actuation can be achieved in untethered soft bio-inspired robots using the bilayer of infrared-actuated thermoresponsive materials, suggesting that other materials with similar properties can also be adopted in a similar method. The proposed method allows for the integration of different active materials toward the realization of infrared-driven, untethered reversible, and reprogrammable actuators for soft bio-inspired robots.