Robust control of unconstrained maneuver and collision for a robot manipulator with bounded parameter uncertainty

The design of a robust nonlinear feedback controller is addressed for an N-degree-of-freedom robot with bounded uncertainty in the dynamic model´s parameters. It is demonstrated that the proposed controller makes the robot system practically stable when both unknown payload variation and joint frictional force are taken into consideration. It is also shown that this controller can guarantee the practical stability of the robot system when a collision between the robot and its environmental occurs. Sufficient conditions for global practical stability are derived using Lyapunov´s second method. A numerical simulation of a two-link robot manipulator with bounded parameter to illustrate the proposed control system