Phased Predictive Berthing Control in Low-Speed Maneuvering for Autonomous Inland Ships

Journal article, 2026

To address the challenges of safe and efficient automatic berthing for underactuated inland ships without tugboat or lateral thruster assistance, this article introduces a phased predictive berthing control (PPBC) method designed for low-speed conditions with uncertainties. A maneuvering modeling group (MMG) model is initially developed, incorporating twin-propeller and twin-rudder configurations, environmental disturbances (i.e., wind and currents), and model uncertainties. Three distinct berthing strategies, i.e., bow-in berthing, parallel berthing, and stern-in berthing, are formulated to ensure the applicability for most of berthing scenarios with phased states constraints. A time-delay observer is designed to estimate environmental disturbances and model uncertainties, on the basis of which a reliable predictive model is constructed by using the low-speed MMG model and the estimated disturbances and uncertainties. Leveraging this model, a model predictive control (MPC) method is designed to achieve the trajectory tracking of berthing control, while accounting for both control input and phased-state constraints. Simulation results demonstrate that the proposed PPBC method outperforms conventional proportional–integral–derivative, sliding mode control, and standard MPC methods in terms of trajectory, heading, and speed tracking error across a range of evaluated berthing scenarios.