Mitigating roll–pitch motion by a novel controller in dynamic positioning system for marine vessels

ABSTRACT

In general, a three degree-of-freedom (DOF) horizontal motion control has been regarded as adequate in the design of a dynamic positioning system (DPS). However, for certain marine constructions, especially those with a small waterplane area and low metacentric height, which results in relatively low hydrostatic restoring compared to the inertia forces, an unintentional coupling phenomena between the vertical plane and the horizontal plane through the thruster action can be invoked. A novel roll–pitch motion controller with horizontal motion control law is proposed in this paper. The roll and pitch proportional controller is first introduced into the DP control law. The performance of the newly proposed controller was demonstrated by time-domain simulations for a dynamically positioned semi-submersible.

KEYWORDS:

• Roll and pitch motion control
• dynamic positioning system
• unintentional coupling phenomena

Acknowledgments

We thank the editor and the anonymous reviewers for suggesting valuable improvements to the paper.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors greatly acknowledge the support of the National Key Basic Research Development Plan (973 Plan) Project of China [grant number 2013CB036103]; the Ministry of Industry and Information Technology (Mooring position technology: floating support platform engineering(II)); the National Key Research and Development Program of China [grant number 2016YFC0303405]; the Shanghai Sailing Program [grant number 17YF1409700].