A Decision-making Method for Lane Changes of Automated Vehicles on Freeways Based on Drivers' Dissatisfaction

In this study, a decision-making method based on drivers' dissatisfaction is proposed in order to carry out lane changes on freeways and meet the requirements of safe and efficient driving, smooth decision-making results, and combined with a motion planning module to guide the vehicle's movement. First, a model of drivers' dissatisfaction was established, which was used as the basis for generating intentions of lane changes. Second, two types of efficiency strategies were built, according to the motion states of obstacles in different lanes, and a prediction engine was designed to forecast and evaluate candidate lanes. The lane with the higher driving efficiency was then selected as the target lane. Third, the minimum safety spacing model of lane changes was applied to ensure safety throughout the whole process of lane changing. The resultant target lane was then provided to the motion planning module, based on an improved artificial potential field, to identify the goals of movement. Finally, a variety of scene tests of the integration algorithms were carried out on the CarSim/PreScan/Simulink co-simulation platform as well as on the hardware-in-the-loop platform. The simulation results demonstrate that the algorithm can generate stable lane change intentions based on the accumulation of drivers' dissatisfaction, select the target lane with higher driving efficiency, guarantee the safety of lane changes throughout the whole process, and deal with unexpected situations such as the sudden acceleration or deceleration of obstacle vehicles. Simultaneously, by changing the target lane, the motion planning module can automatically adjust the vehicle's movement to enable car following and lane changing. © 2019, Editorial Department of China Journal of Highway and Transport. All right reserved.