- Large motion responses of offshore platforms in harsh environment in deep water are of great concern for the operation and design of the platforms. Thruster-assisted position mooring systems can be applied to avoid excessive motions of the platforms. Fully coupled dynamic analysis of a thruster-assisted turret-moored Floating, Production, Storage, and Offloading unit was performed. Kalman filtering, PD control, and thrust allocation were linked with the hull/mooring/riser time-domain coupled dynamic analysis program called WINPOST-FPSO. The numerical example illustrates general performance of a thruster-assisted turret-moored FPSO and shows that the mooring/riser tensions are reduced.