Control design and allocation of an over-actuated triangular floating platform

This paper presents the design and practical implementation of an autonomous dynamic positioning scheme, i.e., the stabilization of linear and angular velocities as well as the position and orientation, of a novel triangular floating sea platform. The required closed-loop forces and moments must be provided by three rotating pump jets, located at the bottom of three partly submerged cylinders located at the three corners of the platform. With this control configuration the platform is over-actuated, i.e., it has more control inputs than degrees of freedom (DOF). Design rules that maximize the manipulability of the platform, and a control allocation scheme that allows goal realization without violating thruster capabilities are developed. Simulations results, including environmental disturbances, are presented that demonstrate the performance of the controller, and the allocation scheme employed.