An adaptive compliance position control based on EKF for series elastic actuation

Considering the intrinsic safety of physical human-robot interaction, this paper proposes a compliance Cartesian position control of robot manipulator with series elastic actuations(SEA). High spring compliance introduces strong passive dynamics to improve safety. A kinetics model of manipulator was built to investigate the effect of applying driving forces. Without adopting the inverse dynamics, an adaptive control method positioning the end-effector to reach the target point was demonstrated based on torque control. The introduction of probabilistic model helps to improve system performance in many aspects including response speed, error rejection and robustness. Both simulation and experimental results shown that the system can be stopped or disturbed safely and stably while it was operating in an unconstructed environment.