Research On The Algorithm Of Coordinated Collision Avoidance In Partial-Connected Driving Environment

As one of the hottest topics in Intelligent Transportation Systems, Connected Vehicles get more and more attention in recent years. Unlike the USA, Japan and Europe, China carried out research of Connected Vehicles rather late. It has been less than 10 years since China started the research under government support. But the research of Connected Vehicles develops very fast in China. Many automotive corporations have taken part in the research of Connected Vehicles technology. However, before fully applying Connected Vehicles technology in real world, there will be a period of transition during which connected vehicles and non-connected vehicles both exist. In this partial-connected driving environment, many applications based on Connected Vehicles will be limited or even completely invalid. This really goes against the development and popularization of Connected Vehicles technology. In order to make full use of the information provided by Connected Vehicles technology, there will be a new problem of developing safety applications aimed at partial-connected driving environment. Moreover, the problem of how connected vehicles impact on non-connected vehicles and even the whole vehicle group’s safety in the partial-connected environment is also worthy of attention in the application of Connected Vehicles technology. Aimed at these two problems, this paper carries out the following studies.(1) The concept of relative kinetic energy density is proposed and a coordinated collision avoidance algorithm is desighed based on minimizing the total relative kinetic energy density. Simulations of this algorithm under model predictive control have been implemented. By analyzing the results of 1000 simulation experiments where the scenario is that the first vehicle in a group of 10 vehicles executes an emergency brake, the performance of the proposed algorithm is validated.(2) Based on the feasibility analysis on the implementation of the proposed algorithm in partial-connected driving environment, some modifications have been made in the algorithm. By employing an improved driver psychological model, simulations are implemented. The relationship between connected vehicles and the safety of the vehicle group is analyzed.(3) Focusing on the scenario in which the first vehicle in a group of 10 vehicles applies an emergency brake, amounts of coordinated collision avoidance simulations under different penetration rates of connected vehicles have been carried out. By analyzing the simulation results, the quantitative relationship between the penetration rate of connected vehicles and the safety of vehicle group is uncovered. And the specific penetration rates with the highest efficiency in improving safety and decreasing chain collisions are found. Moreover, the influence of connected vehicles on the braking intensity of non-connected vehicles is also analyzed.(4) A test platform for multi-vehicle cooperative control is built. Based on the platform, an experiment in which the first vehicle in a group of 3 vehicles executes an emergency brake is conducted to validate the positive influence of connected vehicles on the vehicle guoup.The study shows that by developing coordinated safety applications, connected vehicles can improve the vehicle group’s safety in partial-connected driving environment and the improvement increases with the penetration rate of connected vehicles. Therefore, Connected Vehicles technology is worthy to be further studied, popularized and widely applied.