Hard contact surface tracking for industrial manipulators with orientation control and (SR) position based force control

We present a hybrid control concept that solves a wide range of surface tracking tasks for manipulators with defined contact to (moving) rigid objects. The definition of contact includes a contact force between end-effector and work-piece, as well as orientation angles relative to the surface and the tracking direction. Position based neural force control (NFC-P) consists of a hybrid force/position controller that accurately generates contact forces to objects with arbitrary flexibility and uncertain distance or shape. Orientation control is realized by a supplementary module in the control loop, using force and position sensor signals. Disturbances in force control are caused by joint friction, and a neural friction compensation is developed. NFC-P includes a neural trajectory generating tool for smooth and kinematically valid contact movements. The kinematic mappings guarantee singularity robustness (SR) in the entire workspace