Continuous-time system identification of the steering dynamics of a ship on a river

Abstract

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.

Keywords:

• parameter identification
• continuous-time system
• sensitivity analysis
• ship dynamics

Acknowledgements

The authors thank Professor Ernst Dieter Gilles and the Max-Planck-Institut für Dynamik Komplexer Technischer Systeme, Magdeburg, Germany where Arturo Padilla did part of the work presented in this paper and from where the navigation data were obtained.

Additional information

Funding

This work is supported by UFro, UTFSM and CONICYT-Chile [grant number ACT 53], [grant number FONDECYT 1130861].