Reduced order unknown input observer based distributed fault detection for multi-agent systems

This paper is devoted to the problem of distributed fault detection for multi-agent systems. A reduced order unknown input observer based fault detection method is proposed. By constructing reduced order unknown input observers in one agent, the fault in its neighbor can be detected. In the observer design process, only the measurement output of the neighbor agents is used. Two cases are considered. For the case that the observer matching condition is satisfied, the influence of unknown input on residual is removed completely; if this condition is not satisfied, the influence of a part of unknown input is removed, and the influence of the other part is attenuated. Compared with the existing results, the overall dimension of all the observers is decreased greatly. At last, two examples are given to show the effectiveness of the fault detection method.