###### Abstract  
For the design and verification of a motion control algorithm for unmanned surface vehicles, a simulation system is developed based on VRX and Simulink. Firstly, considering the effect of wind, a dynamic model of the USV with padded propellers is established. Secondly, combined with speed control, three control modes are considered, including yaw rate control, heading control, and path-following control, and speed, heading, yaw rate, and path guidance controllers are designed. Then, a real-time simulation system is developed based on the Virtual RobotX (VRX) environment and the Simulink ROS2 toolbox. Finally, motion control simulation experiments under three control modes and a path-following water tank experiment are carried out. The designed simulation system can simulate the motion of USVs and different environmental elements, such as wind, intuitively and realistically. In simulation experiments, the designed controllers can make the USV follow commands quickly and accurately under three control modes. In the water tank experiment, the USV could stably track the desired path with a relatively small tracking error. Therefore, the effectiveness of the simulation system is strongly confirmed through simulation experiments and the water tank experiment. The simulation system will be expanded in the future for more research on target recognition, path planning, and other aspects of USVs. USV; ROS2; Simulink; motion control; simulation system; VRX 2025  
31 March  
Gazebo, as a 3D simulation component of Robot Operating System (ROS), supports various physics engines such as ODE, DART, Bullet, etc., and can simulate various mechanical phenomena, such as the forces acting on USVs in water. Secondly, Gazebo's modular structure allows for the extension of its core functionality through plugins. By customizing sensor plugins, multiple sensors can be simulated, such as cameras, LiDAR, GNSS, IMU, etc. [PERSON] et al. [3] designed a virtual simulation platform for USVs based on ROS and Gazebo, considering disturbances such as wind, waves, and currents. Virtual testing experiments were conducted on a certain type of USV to evaluate its perception, trajectory tracking, and autonomous obstacle avoidance performance, verifying the effectiveness of using the platform to test and evaluate USV's autonomous navigation performance. [PERSON] et al. [4] developed the USV simulation platform USVSim based on ROS and Gazebo by improving the hydrodynamic and buoyancy plugins of the underwater robot simulation platform Freefloating, achieving high-fidelity simulation of USV motion under environmental disturbances such as wind, waves, and ocean currents. [PERSON] et al. [2] proposed a comprehensive simulation system for USVs based on USVSim ([[https://github.com/disaster-robotics-proalertas/usv_sim_lsa](https://github.com/disaster-robotics-proalertas/usv_sim_lsa)]([https://github.com/disaster-robotics-proalertas/usv_sim_lsa](https://github.com/disaster-robotics-proalertas/usv_sim_lsa)) accessed on 30 March 2025) and MATLAB ([[https://www.mathworks.com](https://www.mathworks.com)]([https://www.mathworks.com](https://www.mathworks.com)) accessed on 30 March 2025), which meets the requirements for the rapid development and simulation testing of USV navigation control systems. Virtual RobotX (VRX) is an open-source 3D simulation platform for unmanned surface vessels developed by organizations including the Open Source Robotics Foundation (OSRF). The platform originates from the Maritime RobotX Challenge, which has been held every two years since 2014 and includes tasks such as autonomous path planning, automatic docking, buoy search and detection, and obstacle avoidance [5; 6; 7]. The current VRX version was developed based on the second-generation robot operating system ROS2 framework.