Trajectory tracking control for multi-thruster AUV considering thruster delay effects

This paper studies the problem of trajectory tracking control for a multi-thruster Autonomous Underwater Vehicle (AUV) considering the effects of thruster delays. An improved adaptive backstepping sliding mode control strategy (IABSMC) is proposed to ensure accurate trajectory tracking. By utilizing an adaptive disturbance observer, the disturbances experienced by the AUV during underwater driving can be effectively observed. To settle the potential issue of thruster delays, a thrust allocation algorithm based on Particle Swarm Optimization (PSO) and Model Predictive Control (MPC) is introduced in this paper. This algorithm enables real-time allocation of thrust between delayed and normal thrusters, reducing the negative effect of thrust delays. Results indicates that, compared with Sliding Mode Control (SMC), the proposed control strategy is more effective in reducing tracking errors and maintaining stability in the presence of thruster delay. It also exhibits good inhibition of chattering, and the adaptive disturbance observer effectively observed the interference caused by underwater currents.