Fault-tolerant Tracking Control for Mobile Robots Based on the Framework of Intermediate Estimator and MPC

During the actual motion of the wheeled mobile robot(WMR), actuator faults caused by ageing or system components' misoperation may significantly impact the real-time control performance. Therefore, this paper proposed a fault-tolerant tracking control approach based on MPC and intermediate estimator (IE) that the observer matching condition need not be satisfied. First, a set of reference trajectories is generated from the virtual system, and a nominal tracking error system is obtained based on the relative position of the actual system. Then, an IE is used to estimate the state error and actuator fault of WMR so that an estimation-based predictive model and a fault-compensated composite control law can be obtained to ensure stable control of WMR with an actuator fault. Finally, the simulation that compared to the nominal MPC showed that this fault-tolerant control algorithm has good performance in adapting to actuator faults, which verifies this algorithm's effectiveness.