Distributed PI Observer-Based Sensor Fault Estimation in Networked Multi-Agent Systems with Application to Unmanned Ground Vehicles

This paper addresses the problem of distributed sensor fault estimation (FE) in leader-following multi-agent systems (MASs) composed of unmanned ground vehicles (UGVs). In consensus-based formation control, sensor faults affect the local measurements exchanged among neighboring agents, degrading state estimation and compromising the tracking performance of the entire fleet. Although fault estimation techniques have been widely investigated, most existing distributed formulations do not explicitly address sensor FE within a leader-following consensus framework. A distributed Proportional–Integral (PI) observer is proposed to simultaneously reconstruct the agents’ states and estimate sensor fault signals using local and neighbor information. The observer and the leader-following consensus controller are considered within a unified design framework, and sufficient conditions for the simultaneous synthesis of the observer and consensus-controller gains are derived in terms of linear matrix inequalities (LMIs). The proposed methodology is validated through a cooperative UGV formation scenario, where simulation results demonstrate the ability of the distributed observer to reconstruct sensor fault signals and illustrate the effect of sensor faults on the leader-following tracking performance. The proposed approach focuses on sensor fault estimation and does not incorporate an active fault compensation mechanism.