Adaptive Decentralized Prescribed Performance Fault‐Tolerant Control of Interconnected Nonlinear Time‐Delay Systems With Input Dead‐Zone and Saturation

Abstract

This article addresses the problem of adaptive prescribed performance control for interconnected nonlinear systems with time delays in the presence of sensor and actuator faults, input saturation, and dead‐zone nonlinearities. The objective is to achieve accurate reference tracking while ensuring boundedness of all closed‐loop signals under multiple practical constraints. To this end, a delay‐independent adaptive state‐feedback control scheme is developed by combining the dynamic gain technique with a backstepping design framework. A smooth compensating function is introduced to mitigate the effects of unknown disturbances and faults. The nonlinearities arising from input saturation and dead‐zone are approximated and transformed into an affine form using the mean value theorem. By properly selecting the initial conditions of the scaling function, semi‐global or global asymmetric prescribed performance is guaranteed. The total system's stability is determined using Lyapunov‐based analysis. The findings show that, in spite of temporal delays and fault circumstances, the suggested strategy guarantees precise tracking for every subsystem while meeting specified performance limits. Simulation studies verify the suggested control strategy's efficacy and usefulness.