A variable admittance controller for human-robot manipulation of large inertia objects

In this work, the problem of cooperative human-robot manipulation of an object with large inertia is addressed, considering the availability of a kinematically controlled industrial robot. In particular, a variable admittance control scheme is proposed, where the damping is adjusted based on the power transmitted from the human to the robot, with the aim of minimizing the energy injected by the human while also allowing her/him to have control over the task. The proposed approach is evaluated via a human-in-the-loop setup and compared to a generic variable damping state-of-the-art method. The proposed approach is shown to achieve significant reduction of the human’s effort and minimization of unintended overshoots and oscillations, which may deteriorate the user’s feeling of control over the task.