T. Lauvdal et Ti. Fossen, A GLOBALLY STABLE ADAPTIVE SHIP AUTOPILOT WITH WAVE FILTER USING ONLYYAW ANGLE MEASUREMENTS, Modeling, identification and control, 17(2), 1996, pp. 107-119
A stable minimum phase transfer function from rudder angle to yaw angl
e is used to design a globally stable adaptive ship autopilot. First-o
rder wave disturbances in yaw are filtered by applying a notch filter.
Integral action is introduced by using a reference model technique. G
lobal stability is proven for the total system which include the yaw r
ate observer, the parameter update law, the feedback controller, the n
otch filter and the integral part of the controller. The simulation re
sults showed that the performance is excellent, even with no a priori
knowledge of the ship parameters.