3.1.2. Visual Simulation Based on Unity3D

The visual simulation module includes scene resources and unmanned platform models. The scene resource module is responsible for the construction and optimization of 3D scenes in the visual simulation software, and makes the scenes restore the real environment as much as possible to run smoothly through the 3D model import and level of detail (LOD) optimization. Multiple unmanned platforms can be loaded in the simulation scene according to the demand, and the objects can be driven to move according to the immediate feedback of the data in ROS. Particle effect components are used to simulate weather, such as rain and fog. The light was set in the Unity scene to simulate a sunny day, dusk and night. Various meteorological and light environments were combined to simulate different visibilities in the real world. Lastly, the virtual RGB images were obtained through the Unity camera module.

**Figure 5.** The virtual data generation program is deployed on Computer A, and the agent handler and cooperative location program is deployed on Computer B. They are connected using a gigabit network.

**Table 1.** The hardware configuration of the computers running the virtual simulation platform and the positioning algorithm.

