Distributed Fault-Tolerant Bipartite Output Consensus Control for Descriptor Discrete-Time Uncertain Multiagent Systems

This article addresses the bipartite output consensus problem for descriptor discrete-time multiagent systems (MASs) subject to both process faults and parameter uncertainties. The study is framed within multiagent cyber–physical systems (CPSs), aiming to achieve secure and resilient consensus in adversarial environments characterized by directed signed topologies. To achieve simultaneous estimation of system states and fault signals under discrete-time descriptor dynamics, a new distributed estimator is designed by integrating the directed signed graph topology with a discrete-time generalized algebraic Riccati equation (ARE). Furthermore, a distributed observer is constructed for each follower to track the exosystem state, enabling the bipartite tracking of reference trajectories across two opposing subgroups. This design effectively accommodates exosystem matrices whose eigenvalues lie entirely outside the unit circle, thus relaxing the conventional neutral-stability requirement. Based on the$p$-copy internal model principle from robust output regulation theory, a distributed fault-tolerant output-feedback control law is synthesized. This controller guarantees bipartite output consensus over directed signed networks in the presence of concurrent process faults and model uncertainties. Finally, a numerical simulation validates the feasibility and effectiveness of the proposed approach.