Interactive redundant robotics: control of the inverted pendulum with nullspace motion

In the growing field of service robotics the interaction between humans and robots is an important topic. In this paper the interactive features of the kinematically redundant DLR lightweight robot axe presented. At the example of an inverted pendulum the "interactive nullspace motion" is introduced, where the user is able to modify the configuration as a subtask while balancing the pendulum as primary task. Different ways of nullspace interaction are shown, either contact-free by a teach-device or a position tracker, or by touching the robot, whereas the joint torque sensors measure the external touch.