Robust Cooperative Fault-Tolerant Control for Discrete-Time Multi-Agent Systems With Uncertainties and Actuator Faults

In this paper, we address a class of distributed robust cooperative fault-tolerant control problems for discrete-time multi-agent systems (MASs). The discrete-time MASs considered in this paper have both uncertainties and actuator faults, and a distributed intermediate variable estimator that does not require a fault estimation matching condition is designed for obtaining the estimation information of the actuator faults. In addition, to further obtain higher design freedom and better estimation performance, the intermediate variable estimator considers both centralised and distributed output estimation errors as feedback terms. A fault-tolerant control protocol is designed using the fault estimation information to ensure the reliable operation of discrete-time MASs. It is worth noting that in the method proposed in this paper, there is no need to know the boundary information about the faults and their changing rates, and the method is applicable to discrete-time MASs with directed communication topology. In order to ensure the solvability of the Linear Matrix Inequality (LMI) for better obtaining of the gain matrices of the designed fault estimators, further decoupling and dimensionality reduction of the LMI are carried out in this paper. Finally, a numerical simulation and a network of four one-link flexible joint manipulator systems simulation verify the truthfulness and effectiveness of the method proposed in this paper.