A Smooth Uniting Controller for Robotic Manipulators: An Extension of the Adaptive Variance Algorithm (AVA)

The compliant behavior that a robotic manipulator realizes in the proximity of the desired goal is typically undesirable when the robot starts far away from the goal itself. In the latter case, high gains can produce motor torques which are unfeasible or too dangerous for interactions with humans and the environment. In this paper, a control algorithm is proposed that guarantees smooth high-gain/low-gain transitions to accommodate both the local and global requirements. The building block for this method is the recently proposed Adaptive Variance Algorithm (AVA). The theoretical proof of the result is validated with experiments on a humanoid robot.