A sliding manifold approach to the feedback control of rigid robots

In this paper we propose a sliding manifold approach to the control of rigid robotic manipulators. We design a PD feedback controller via singular perturbation theory which guarantees the tracking of a reference trajectory. The control signal tends during a fast transient to the well-defined equivalent control with fast nonoscillating modes and then it remains close to this in the uniform topology. Then the resulting closed-loop system does not have the drawbacks of high-gain feedback systems, even if it retains robustness properties with respect to disturbances and plant parameter uncertainties. An application of the proposed procedure to a robotic system which includes actuator dynamics and tachometers is presented.