Impact of Thruster Interaction Effects on Optimal Thrust Allocation in Dynamic Positioning Systems

Existing strategies and proposed methods for optimal thrust allocation in dynamic positioning systems of floating objects are primarily focused on minimization of power consumption with treating of numerous limitations and conditions that should be satisfied at the same time. On the other hand, one can notice that thruster interaction effects such as axial and transverse current, thruster-hull interaction, thruster-thruster interaction and ventilation are rarely taken into account. These effects, whether they occur separately or in combinations, can cause significant thrust losses which can consequently degrade reliability of dynamic positioning systems, decrease accuracy, increase response time and power/fuel consumption, etc. The main goal of this paper is quantification of selected aforementioned effects as well as the proposal of their implementation in optimal thrust allocation strategies based on Moore-Penrose pseudoinverse matrix. Moreover, the thrust allocation procedure here considered has been performed with and without thrust loss effects together with comparative analysis of these two approaches.