In this study, we consider the parameter estimation problem of a ship dynamics model. We consider two possible approaches to identify a continuous-time model from real data obtained on a river, where the presence of disturbances is a key issue. The first approach is identification through optimisation using a disturbance observer. The second approach corresponds to the refined instrumental variable method for linear parameter varying systems. In addition, we evaluate the accuracy of the parameter estimation through a sensitivity analysis. The obtained results show an improvement in the parameter estimates compared to identification procedures that do not consider the river disturbances. The application of the model for track-keeping control is also illustrated.

The methods presented in this paper were designed to improve the performance of a control scheme for the automatic track-keeping of inland vessels. The performance of this control scheme heavily depends on the underlying models as it employs model inversion for the calculation of feedforward input signals and reference trajectories for feedback control. However, vessels on rivers are subject to model uncertainties as well as disturbances, such as cross currents or wind. Therefore, an estimation scheme was designed for the estimation of disturbances and their integration into the model inversion procedure. Simulation results show the usefulness of the presented methods for various disturbances and model uncertainties.

This paper presents a path planning method for lock entering maneuvers that is based on nonlinear programming. Fairway boundaries, lock walls and the input saturation of the thrust devices of the vessel are accounted for as inequality constraints in the optimization. The environmental constraints are modeled as polygons or constructive solid geometry objects. Each of the methods is used to compute a path for a typical inland vessel with a bow thruster and a rudder and propeller configuration.

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