Fixed-time NN-based adaptive fault-tolerant control for heterogeneous vehicular platoon system with improved exponential spacing policy

This paper is concerned with the distributed fixed-time neural network adaptive tracking control issue for heterogeneous vehicular platoon suffered from actuator faults. Due to the string instability of vehicles caused by non-zero initial spacing errors (ISEs), an improved exponential spacing policy is proposed to eliminate the influence of non-zero ISEs by introducing a compensated term, while guaranteeing the traffic flow stability. Subsequently, a fixed-time platoon control scheme is constructed, where the singularity problem caused by the negative exponent terms of controller is addressed by introducing a cosine-based scalar function. Moreover, the influence of actuator faults and uncertainties for vehicular platoon system is decreased with the control scheme, where the instability caused by maximum acceleration is avoided. The internal stability and string stability of the closed-loop system are proven through Lyapunov stability analysis. The simulation example and comparison results testify to the reliability of control scheme.