To address the control requirements for automatic berthing and unberthing of unmanned surface vehicles (USVs) in high sea states and complex water environments, this paper investigates ship navigation control strategies and safety assessment methods. Wave loads are decomposed into first-order and second-order wave forces through wave spectrum analysis, enabling real-time dynamic response modeling of the vessel. Secondly, a three-degree-of-freedom optimal control algorithm integrating wind and current feedforward compensation is proposed, combined with ship seakeeping analysis. A multi-domain switching mechanism is introduced to optimize the thrust allocation strategy for heterogeneous actuators, enhancing control accuracy and system robustness. Finally, thrust characteristics of multiple control surfaces are calibrated using real-ship experimental data to verify the feasibility and effectiveness of the proposed control algorithm in practical applications. Experimental results show that the proposed method achieves meter-level control accuracy during automatic berthing and unberthing, with a berthing angle error of less than 1 \(^\circ \) and a berthing speed of less than 1 kn, demonstrating safe and efficient automatic berthing and unberthing capabilities.