51Sim-One is the first domestic intelligent vehicle simulation tool with independent intellectual property rights independently developed by 51WORLD. The 51Sim-One is applied to the research and development of common technologies for various types of autonomous driving systems. It provides a safe and controllable all-element multi-level for intelligent decision-making control, complex environment perception, human-machine interaction and co-driving, vehicle-road collaboration and network communication. Testing and evaluation of technical support. The simulation engine of 51Sim-One has expanded to serve smart city transportation systems, traffic environment simulation, smart road facility deployment and monitoring, and wireless network construction evaluation.