Digital implementation of adaptive control algorithms for robot manipulators

A hybrid direct adaptive motion control law for robot manipulators is presented. The algorithm is hybrid in the sense that the linear portion of the controller is continuous-time, while the parameter adaptation law is discrete-time. The algorithm utilizes the desired joint signals instead of the actual manipulator joint signals in the computation of the control and parameter adaptation laws. The algorithm is extremely computationally efficient when the desired trajectories are known in advance. The stability of the algorithm is proven utilizing the full nonlinear model of the manipulator in the analysis, and without linearization of the manipulator dynamic equations. The full digital implementation of this algorithm is also discussed, and experimental results on the control of a two-degree-of-freedom SCARA arm are presented