Motion control of marine craft using virtual positional and velocity constraints

Recently, [1] put forward a multi-body representation for modeling and control of formations of marine craft. In this paper, the same line of reasoning is taken one step further and the method is generalized for the cases that include speed assignment tasks. The proposed algorithm is then applied to design a novel path-following controller, in which the control objectives are formulated using virtual positional and velocity constraints, and the control problem is regarded as a constrained multi-body system. Global exponential stability of the error system is proved using the Lyapunov method. Also, global boundedness of the unactuated dynamics is demonstrated in the case of underactuation.