Replicating Human Stiffness Profile with a Cartesian Impedance Controller in Realtime

Abstract

In this chapter, we evaluate the efficiency of the teleimpedance algorithm in two experimental tasks, illustrating different and complementary aspects of the method. The first concerns a classic peg-in-hole task, and is used to illustrate the stability, transparency, and safety characteristics of the method. The second experiment, a ball-reception task, is chosen to assess how effective is the incorporation of human impedance regulation skills in performing tasks with significant dynamics. In both experiments, the slave robot performs the task by tracking both the reference position profile (which corresponds to the endpoint position of the arm of the human operator as measured from an optical position tracking system) and the end-point stiffness profile (estimated from the muscular activities of the operator’s arm) in real-time, via a Cartesian impedance controller. Eventually, the performance of the proposed algorithm is compared to the behavior of the robot arm with different constant stiffness settings.