Design and analysis of a non-backdrivable series elastic actuator

The compliance of series elastic actuators makes them robust to environmental perturbations, and their ability to use impedance control may improve their performance in open-loop environments such as conventional prosthetic control. Series elastic actuators have historically required a backdrivable transmission to ensure adequate bandwidth. The authors have created a non-backdrivable series elastic actuator through the inclusion of a harmonic drive transmission, which contains no backlash; the dominant feature in limiting frequency resolution. The actuator has an acceptable speed and stall torque and an adequate frequency range, and would be used in the future to implement impedance control of prosthetics.