Proportional Integral Observer-based Consensus Control of Discrete-time Multi-agent Systems

The multi-agent consensus control is widely used in industrial application, such as industrial robot, satellite attitude control, etc. Therefore, this paper studies the consensus control problem of multi-agent systems. For discrete-time Lipschitz nonlinear multi-agent systems with unknown inputs, a consensus control algorithm based on proportional integral observer is proposed. Firstly, a proportional integral observer is designed for each subsystem to estimate the system states and unknown input signals simultaneously. Then, a consensus control protocol based on the system state estimation is designed, and H ∞ technique is used to effectively suppress the unknown input signals. Furthermore, the gain matrices of the observer and consensus control are obtained by solving a linear matrix inequality. Finally, two simulation examples show the correctness and feasibility of the proposed method.