Digital redesign of robot control

A continuous nonlinear control law for a robot manipulator is redesigned for digital implementation. The digital control law is derived so that the response of the digital control system is close to that of the continuous control system. The amount of computation for the redesigned control algorithm is almost the same as the amount of computation for the original nonlinear control algorithm. The redesign method provides satisfactorily stable results, even for a fairly large sampling interval. The algorithm was experimentally applied to a direct-drive arm with two degrees of freedom. Simulation and experimental results illustrate the effectiveness of the proposed redesign method