Integrated Actuation and Self-Sensing for Twisted-and-Coiled Actuators with Applications to Innervated Soft Robots

Traditional soft robots require separate sensors and actuators to precisely control their motion. A twisted-and-coiled actuator (TCA) is a new artificial muscle with both actuation and self-sensing capability that can simultaneously serve both as a sensor and an actuator allowing to control the motion of TCAs without external sensors. This paper investigates the integrated sensing and actuation for TCAs, and the self-sensing function is realized by only measuring the TCA's electrical resistance change. The closed-loop control of a single TCA is realized, and an innervated soft finger that can respond to external load without extra sensors is demonstrated. Our results will lay a foundation for integrated sensing and control by directly using the actuator, paving the way for self-contained smart robotic systems (e.g., untethered soft robots).