Research On Driving Comfort Of Two-lane Highway In Mountainous Areas Based On Driving Life Psychological Indicators

On condition that mountainous two-lane highways are limited by topography and geomorphology and because of the relatively closed highway environment,some overloaded sections of the road,high driving risk and less comfortable driving experience,the traffic safety issue has attracted widespread attention.In the process of driving,drivers need to continuously obtain effective traffic information from the highway environment and adjust the driving state so as to cope with the changeable driving environment,which will produce driving load and affect driving comfort.Consequently,to reduce driving risks and improve driving safety,studying the mechanism of highway environment on driving comfort is of great significance.This paper aims to study the changing characteristics of driving comfort,analyze the thresholds of various factors under each comfort level,and provide theoretical support for the improvement of mountain road environment by carrying out driving experiments in different highway environments.First of all,according to the research object design driving experiment,collect highway landscape information,highway longitudinal slope and sign information and other highway environmental parameters,at the same time collect the driver’s biopsychological indicators,data screening,standardization processing of the collected data,etc.,based on the factor analysis method,the four parameters of the screened pupil area change rate,fixation time percentage,heart rate variability and electrodermal mean are reduced dimensionality,and a driving load model that combines the driver’s eye movement characteristics,heart rate characteristics and skin electric characteristics is constructed,based on the driving load value.Driving comfort is divided into three levels:comfortable,more comfortable and uncomfortable,and the threshold range of each comfort level is determined.The highway environmental information was preliminarily screened to determine the landscape information,highway slope and traffic sign information of the studied road section.In addition,based on the enclosure theory,the highway road space is divided into three categories,and the threshold range of each road area space is determined.The gaze behavior of drivers in the three types of road space was analyzed,and the main factors affecting driving comfort in the highway environment were landscape information,highway slope and traffic sign information.The continuity characteristics and color characteristics of the landscape were analyzed,and the HSV color model and the area ratio of open area were used to establish a comprehensive quantitative model of landscape information.Combined with the characteristics of mountain highway signs,based on Shannon’s information entropy theory and the weight of each element in traffic signs,the traffic sign information model and traffic sign information density model are established.Moreover,the variation characteristics of driving load under different highway landscape information,highway longitudinal slope and sign information density are explored,the correlation model between each main factor and driving load is established,and the value range of each main factor is determined based on the driving comfort threshold.The results show that when the driving comfort level is comfortable,the maximum amount of landscape information is 1.558 bits,and the maximum downhill slope of highway is-1.931%.The maximum uphill slope of the highway is 2.495%;The maximum amount of flag information is 41.755 bits/km.Based on driving safety,when the driving comfort level is more comfortable,the quantitative values of each factor determined in this paper are the recommended optimal values.The specific values are:the amount of landscape information should not exceed 3.214bits;the downhill slope of the highway should not exceed-3.578%;The uphill slope of the highway should not exceed 3.851%;The density of sign information should not exceed 83.155bits/km.Finally,the comfort evaluation expression of highway landscape information,highway longitudinal slope and sign information density is constructed,and the entropy weight TOPSIS method is used to construct a driving comfort evaluation system for mountainous two-lane highway based on driving life psychological indicators,and based on the universality of the evaluation system verified by examples,the driving comfort value of each road section is quantified and ranked,and improvement measures are proposed to provide a theoretical reference for the rational creation of highway environment.