Bio-Inspired Actuation and Sensing

The superb ability of animals to negotiate rough terrain has caused engineers to focus on mechanical properties of muscle and other unique features in order to design improved robots for exploration. This paper reviews recent work in artificial muscle actuators, as well as a new sensor based on a robotic model of the muscle spindle cell. The actuator contains a pneumatic force generator in parallel with a non-linear damping element and in series with a non-linear elastic tendon. Work loop experiments were performed to characterize this actuator under conditions similar to real locomotion at different speeds. The robotic muscle spindle is an 8 × 1 cm device which simulates the response of the physiological muscle spindle to stretch. Its non-linear properties are thought to contribute to stable accurate control over a wide range of motion.