Constrained Control for Cloud Robotic Under Time Delay Based on Command Governor With Interval Estimation

The constrained command tracking problem for the cloud robotic system with unknown bounded time-varying delays is considered. Based on a novel predictor-observer approach, a command governor is proposed to modify the received command in order to guarantee the constraint enforcement of remote robot. We firstly use a prediction algorithm in the forward channel to generate a virtual command, which is close to the original one as much as possible when the danger of constraint violation exists. Then, to deal with the measurement delay and disturbance in the backward channel, interval estimations of the system states are applied instead of delayed measurements in the prediction algorithm of the command governor. The constraints can be rigorously enforced with the upper and lower estimations. The efficiency of the proposed approach is demonstrated by simulations in the case of a single-degree-of-freedom manipulator.