Fixed-time output feedback trajectory tracking control of marine surface vessels subject to unknown external disturbances and uncertainties

• Published in: ISA transactions Vol. 93; pp. 145 - 155
• Main Authors: Zhang, Jingqi, Yu, Shuanghe, Yan, Yan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.10.2019
• Subjects: Adding a power integrator (API); Fixed-time control; Fixed-time extended state observer (FESO); Marine surface vessels (MSVs); Trajectory tracking; Fixed-time extended state observer (FESO); Fixed-time control; Trajectory tracking; Adding a power integrator (API); Marine surface vessels (MSVs)
• ISSN: 0019-0578; 1879-2022; 1879-2022
• DOI: 10.1016/j.isatra.2019.03.007

This paper proposes a novel fixed-time output feedback control scheme for trajectory tracking of marine surface vessels (MSVs) subject to unknown external disturbances and uncertainties. A fixed-time extended state observer (FESO) is proposed to estimate unknown lumped disturbances and unmeasured velocities, and the observation errors will converge to zero in fixed time. Based on the estimated values, a novel fixed-time trajectory tracking controller is designed for an MSV to track a time-varying reference trajectory by the extension of an adding a power integrator (API), and the tracking errors can converge to zero in fixed time as well. Additionally, the convergence time of the controller and the FESO is independent of initial state values. Finally, simulation results and comparisons illustrate the superiority of the proposed control scheme. •A fixed-time extended state observer (FESO) is proposed.•A novel fixed-time output feedback control scheme is proposed.•The observation errors and tracking errors converge to zero in fixed time.•The convergence time is independent of initial states of a vessel.