Research On Vehicle Lane-changing Model And Lane-changing Decision In Urban Roads

Vehicles frequently change lanes in urban road.Reasonable discretionary lane-changing can relieve traffic pressure and increase the capacity of road traffic,consciously turning to lane change according to traffic regulations can maintain normal traffic order.However,Lane-changing of vehicle become the major cause of urban road traffic accidents in recent years.Its safety issues have to cause people's attention.Therefore,it is particularly important to study the lane-changing model and lane-changing decision of urban road vehicles.First,the thesis analyzes the behavior of lane-changing from the operating characteristics,incentives and classification.According to the behavior of lane-changing,the lane-changing process is divided into three stages: lane-changing intent,safety analysis and lane-changing execution.The stage of safety analysis is divided into three typical cases according to the order of the critical collision time of each car.The factors affecting lane-changing are analyzed from the aspects of vehicle type,road and traffic flow.The demand for discretionary lane-changing and the strength of the turning lane-change are modeled by using of fuzzy theory.Through the vehicle trajectory on road,it is verified that the model has a higher recognition rate for the vehicle to perform lane change or not to perform lane change.Based on the model output results,the initial decisions for lane-changing are given.Then,according to the movement state and relative position of the lane-changing vehicle and the surrounding vehicles,the kinematics principle was used to establish lane-changing safety distance model.Through Matlab simulate the change of vehicle uniform speed and uniform acceleration of the minimum initial longitudinal safety distance required in the three situations of the security analysis stage.If the relative distance between the lane-changing vehicle and surrounding vehicles of the lane-changing is not within the safe area at the initial time,the speed and distance can be adjusted by changing the speed and distance before changing lanes to allow the lane-change vehicle to enter the safe area.According to the results of simulation,the vehicle safety lane change decision is analyzed.The initial lane-changing distance in the actual lane change track is compared with the minimum initial longitudinal safety distance required by the model in the same state.The analysis finds that the initial distance of the actual lane-changing is within the initial range of the model's solution,thus verifying that the vehicle lane-changing safety distance model is feasible.Finally,a complete information static non-cooperative game model is established by using game theory.According to the Nash equilibrium solved by the model,the respective optimal strategies are given to provide basis for solving vehicle lane-changing decision under complex conditions.