Abstract: A virtual scene including road is constructed by using software Creator, the scene and several vehicle models are added to the simulation software Vega, the car being controlled is operated by mouse and keyboard, other model vehicles’ paths are set in advance and all kinds of parameters relating to navigators in every segment are edited in Path Tool; based on the established following and changing route distance safety models, a simulation program is created by Vega API in Visual C++ 6.0. Every vehicle’s posture and running parameters can be acquired dynamically by virtue of Vega API functions, a dynamic threshold of safety distance between vehicles can be calculated, then it is possible to judge whether the model car can keep moving straight, change lane or overtake, if it cannot, it will be decelerated or stopped, prompt will appear on the execution interface at the same time, these help taking correct measures actively to avoid collisions. Results show that the process of vehicles’ real avoiding collisions is better simulated in the virtual circumstance; the car being controlled is in an active safety running state.

Key words: Active avoiding collision, Intelligent vehicles, Model of safety distance between vehicles, Virtual realization