Title :
Output Feedback Tracking of Ships
Author :
Wondergem, Michiel ; Lefeber, Erjen ; Pettersen, Kristin Y. ; Nijmeijer, Henk
Author_Institution :
Marine Struct. Consultants b.v., Schiedam, Netherlands
fDate :
3/1/2011 12:00:00 AM
Abstract :
In this brief, we consider output feedback tracking of ships with position and orientation measurements only. Ship dynamics are highly nonlinear, and for tracking control, as opposed to dynamic positioning, these nonlinearities have to be taken into account in the control design. We propose an observer-controller scheme which takes into account the complete ship dynamics, including Coriolis and centripetal forces and nonlinear damping, and results in a semi-globally uniformly stable closed-loop system. Furthermore, a gain tuning procedure for the observer-controller scheme is developed. Experimental results are presented where the observer-controller scheme is implemented onboard a Froude scaled 1:70 model supply ship. The experimentally obtained results are compared with simulation results under ideal conditions and both support the theoretical results on semi-global exponential stability of the closed-loop system.
Keywords :
Coriolis force; closed loop systems; damping; feedback; nonlinear control systems; observers; position control; position measurement; ships; Coriolis forces; centripetal forces; control design; dynamic positioning; gain tuning procedure; nonlinear damping; nonlinearities; observer-controller scheme; orientation measurements; output feedback tracking; position measurements; semiglobally uniformly stable closed-loop system; ship dynamics; Experiments; marine systems; nonlinear control; observer design; tracking;
Journal_Title :
Control Systems Technology, IEEE Transactions on
DOI :
10.1109/TCST.2010.2045654