A Passive Output Feedback Controller with Wave Filter for Marine Vehicles

An output feedback controller with wave filter for regulation of nonlinear marine vehicles is derived. Only measurements of position and attitude are needed. Asymptotic stability for the position and attitude around the desired values, and the velocity about zero is proven by applying Lyapunov stability analysis. Even though the wave filter in this paper has a notch filter structure, it is incorporated in the controller such that the system from the vehicles velocity to the control input is passive. This is opposed to conventional notch filters which are usually designed separately from the controller itself, possibly complicating the stability analysis. Finally, a simulation study of a ship illustrates the design procedure of the controller. Keywords: Marine vehicle control, passive controllers, wave filtering, output feedback controllers. 1 Introduction In the design of marine vehicle controllers, one of the main problems is wave disturbances. To avoid unnecessary use of and wear ..