Coordinating control for a fleet of underactuated ships

In English We consider design of coordinating controllers for a fleet of underactuated ships. Each ship is modeled as a mechanical system with 3 degrees of freedom and 2 control inputs, which are the propeller thrust and the angle of the rudder; presence of lumped environmental forces is assumed. The proposed motion planning procedure relies. on properties of an auxiliary explicitly constructed second order dynamical system. We propose a procedure for motion planning for the whole fleet and for design of a coordinating feedback controller, which stabilizes the motion. In the case when geometric paths for ship motions are given, following our approach, we obtain a description of all feasible motions of the fleet along these paths. In addition, it is shown how to design controllers to counteract environmental forces while remaining on the paths. As a side result, we provide some modifications and give some insights into the weather optimal positioning control design, introduced in 1 for a fully actuated ship model.