Balancing of an inverted pendulum with a kinematically redundant robot

This paper deals with the problem of stabilizing a base-excited inverted pendulum around its upright position with a robot. The pendulum has two rotational degrees of freedom and its base point is moved in two-dimensional space by a planar direct-drive robot. The robot has three degrees of freedom and its kinematic redundancy occurring at the inverse kinematics is utilized to optimize the joint acceleration and the manipulability measure while balancing the pendulum. A decentralized joint acceleration control with a software velocity/acceleration observer is used to accelerate/decelerate each joint of the robot to balance the pendulum. Experimental results are described to show the stable and robust responses of the control system.