Analysis Of Freeway Lane Changing Characteristics And Safety Evaluation Under Bad Weather

The bad weather will not only affect the road surface and the stability of the vehicle,but also greatly affect the driving safety.Lane change is the basic driving behavior in the process of vehicle driving,which has a great impact on the operation of traffic flow.The success of lane change process is directly related to the safety of vehicle itself and surrounding vehicles,especially in the scene where bad weather and lane change behavior coincide,vehicle driving safety is more important.Based on the driving simulation experimental data,this thesis analyzes the lane changing characteristics of vehicles in different weather.On the basis of obtaining the experimental data,defining the lane changing process and screening the lane changing samples,the lane changing probability models under normal,light rain,heavy rain,heavy fog and dense fog are established respectively.According to this,the influence of driving characteristics on lane changing characteristics is analyzed,Based on the entropy weight TOPSIS method,a lane change safety evaluation model is established to evaluate the lane change safety under different weather conditions.The specific research contents are as follows:Firstly,this thesis puts forward the research direction of this thesis according to the mileage of expressway and the current situation of traffic accidents,then combs and analyzes the impact of bad weather on driving behavior and the research status of vehicle lane changing at home and abroad,and systematically expounds the related concepts and classification of bad weather,as well as the definition,types and influencing factors of vehicle lane changing behavior,It lays a theoretical foundation for the later lane change characteristic analysis and safety evaluation.Secondly,the lane change probability model is established.Based on the UC win/road driving simulation experimental platform,this thesis builds five different weather experimental scenes,collects driving behavior data,and uses the laida criterion method to eliminate and process the abnormal values in the data.On the basis of selecting lane change samples,this thesis establishes a lane change behavior description model under five weather conditions based on logistic regression model,and extracts and screens all lane change data,The accuracy and applicability of the model are verified through the comparative analysis of the lane changing process between the model and manual screening.Then,the influence of driving characteristics on lane changing behavior in bad weather is analyzed.In this thesis,the following distance,lane changing duration,lane changing patience time and the maximum steering wheel angle,maximum lateral acceleration and maximum longitudinal deceleration in the lane changing decisionmaking index are selected as the key variables to analyze the lane changing behavior,and the driver’s gender and driving age are taken as the influencing factors,Statistical methods such as one-way ANOVA and post test were used to study the effects of different factors on lane changing behavior under five kinds of weather.Finally,a lane change safety evaluation model is established.Based on SVM-RFE algorithm,this thesis selects 6 indexes from many indexes output by the experimental platform as lane change safety evaluation indexes,and establishes a lane change safety evaluation model based on entropy weight TOPSIS method to evaluate the lane change safety of four kinds of bad weather and normal weather.