Modeling and robust quantitative control for AUV-tow-load system

• Published in: Ocean engineering Vol. 284; p. 114773
• Main Authors: Shi, Yi, Wang, Yanhu, Xie, Wei, Chen, Weixing, Zhang, Weidong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.09.2023
• Subjects: AUV-tow-load system; Quantitative control; Uncertainties and disturbances estimator; Quantitative control; Uncertainties and disturbances estimator; AUV-tow-load system
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2023.114773

This paper models a point-mass load tethered to a single autonomous underwater vehicle (AUV) and proposes a quantitative control strategy, which is able to drive the load to track the desired trajectory closely. The AUV-tow-load system is modeled as three connected subsystems: load position subsystem, cable direction subsystem, and AUV attitude subsystem. Improving on the current prescribed performance control methods, where the transient-state and steady-state tracking behaviors cannot be preassigned accurately, a quantitative controller is designed for the point-mass load position, achieving predefined tracking performance without violating user-defined quantitative indices including overshoot, convergence time, and steady-state accuracy. An uncertainties and disturbances estimator (UDE) is designed and incorporated into the control inputs to compensate for the effects of uncertain dynamics and external disturbances. Rigorous theoretical proof is presented, showing that all tracking errors converge to the neighborhood of zero with quantitatively designed tracking behaviors, obtaining uniformly ultimately boundedness. Simulation results are provided to validate the efficiency of the proposed method. •Designing a general framework that transforms the AUV-tow-load system into three connected subsystems.•Providing a design paradigm for the AUV-tow-load system to assign some quantitative indices on tracking performance.•Employing uncertainties and disturbances estimator to online estimate the lumped disturbances for AUV-tow-load system.