Coupled elastic actuation development for robots as an intrinsic compromise between performance and safety

Up to now, most of robotic systems, consisting of rigid links, electrical servo actuators, tough covers, high-ratio reduction devices, and position sensors, hardly interact with people and environments under safety constraints or move slowly with careful motion planning results with multiple control strategies. This paper proposes a new actuation approach, coupled elastic actuation (CEA), to provide oncoming robots an intrinsic compromise between performance and safety in unstructured environments. One possible prototype of a 1-DOF coupled elastic actuator with adjustable characteristics adaptive to the applied output force and input force is designed to provide a favorable solution to reach a compromise between performance and safety by a Torque Switch mechanism. Both simulations and experiments are presented to show the desired properties of the CEA systems.