Research On Evaluation Of Driving Safety On Snow&Ice Road Based On Driver's Visual Characteristics

Special traffic circumstance of snow and ice road and fault of driver's visual perception are main reasons that cause traffic accidents in winter in cold regions.After snowfall,road and the surroundings are covered by snow and ice so that driver's visual condition becomes worse.Driver's visual behavior changes compared with that under normal driving condition of driving on road without snow and ice covered.Change of driver's visual behavior that results from any changes of elements related to visual behavior could probably threaten driving safety.Thus,it has important guiding significance for preventing and decreasing traffic accidents caused by driver's visual fault,to conduct research on driver's visual characteristics under condition of snow and ice covered road and evaluate driving safety of snow and ice covered road in winter based on driver's visual characteristics,and provides new thought for method of driving safety evaluation of snow and ice covered road.This paper gave an overview of related research status at home and abroad,conducted road test with visual information collection system of Smart Eye combined with theory of driver's visual characteristics,and studied driver's visual behavior under different types of snow and ice covered roads.Specific work of this research is showed below:1)This paper untangled research on driving safety of snow and ice covered road at home and abroad and research of driver's visual characteristic.According to the inadequacies of current research,new thought related driving safety of road covered by snow and ice was brought up in terms of driver's visual characteristic.2)This paper explained characteristics of driver's visual and traffic system of snow and ice covered road,introduced basic forms of driver's eye movement and set up the standard to distinguish between fixation and saccade.Besides,this paper picked up parameters of visual characteristics needed in research on driver's visual characteristics of different types of snow and ice covered roads.Influences of characteristics of traffic system of snow and ice covered road was analyzed theoretically on driver's visual characteristics.3)This paper designed test scheme of visual research on driving safety on snow and ice covered road,built the test platform,conducted road test,collected and preprocessed data of visual information during period of driving on roads covered by different types of snow and ice.4)This paper studied driver's visual behavior of driving on road covered by snow and ice especially from the aspects of fixation and saccade.The variable rules of fixation time,horizontal fixation angle and vertical fixation angle,visual search extend in both horizontal and vertical direction,saccade time,saccade sizes as well as saccade velocity were statistically analyzed.Significant differences of parameters of fixation and saccade collected in roads covered by different types of snow and ice was test by taking the method of nonparametric tests named Mann-Whitney.Single fixation last time,visual search extend in horizontal and saccade velocity was identified as visual evaluation indictors of driving safely on snow and ice covered roads.5)This paper built visual evaluation model of driving safely on snow and ice covered roads based on the approach of AHP&FCE(Analytic Hierarchy Process with Fuzzy Comprehensive Evaluation),established visual evaluation system of driving safely on snow and ice covered roads,identified aggregation of evaluation factors and comments.The weight of all the visual evaluation indictors was calculated based on AHP.Matrix that had fuzzy relationship was built up.At last this paper identified visual evaluation level of driving safely on snow and ice covered roads according to the principle of maximum degree of membership,and then verified applicability of the evaluation model based on actual road and environment conditions.