Goal-driven variable admittance control for robot manual guidance

In this paper we address variable admittance control for human-robot physical interaction in manual guidance applications. In the proposed solution, the parameters of the admittance filter can change not only as a function of the current state of motion (i.e. whether the human guiding the robot ia accelerating or decelerating) but also with reference to a predefined goal position. The human is in fact gently guided towards the goal along some curved paths, where the damping is conveniently scaled in order to accommodate the motion towards the goal position. The algorithm also allows the human to reach goals that he/she cannot directly see because for example the transported object is bulky and obstructs the worker view. The performance of the proposed controller are evaluated by means of point to point cooperative motions with multiple volunteers using an ABB IRB140 robot.