Singular Perturbation Method in Control of Multiple Flexible-Joint Robots

The trajectory-tracking control of a typical industrial robot with six revolute joints is studied, where the joint flexibility is taken into account. An explicit form of the control law is obtained by using the composite control technique. The stability of system is discussed. The global convergence of tracking error can be reached by tuning the controller parameters. This method has a unique advantage in handling a multiple flexible-joint robot as well as hybrid rigid/flexible-joint robot. Numerical simulation on a Fanuc-s430iw heavy-duty robot arm has been performed to verify the control algorithm. Satisfactory tracking performance has been achieved.