Driver’s Visual Cognitiion Safety Research Of Traffci Signs Based On Simulation Technology

As a normal infrastructure, highway traffic signs pass the road and trafficinformation to road users to guide them use the road resources reasonable and orderly.It can promote traffic safety and road operating efficiency. Reasonable informationvolume of traffic signs enables the driver to obtain valid information in a short time,thereby avoiding improper driving behavior, reducing the probability of operator error.However, with the demand of traffic information increased and the road networkencrypted, the information overload condition is generally increased, which increasesthe drivers’ visual recognition burden, and pose security risk. By using the drivingsimulation technology and eye tracker and other equipment, we obtain test data. Thisthesis analyses the drivers’ eye movement parameters and the operational status of thevehicle, and do a research on the reasonable information volume of highway trafficsigns with the purpose of improving the visual cognition safety. This thesis mainlycarries out the work of the following aspects:First of all, summarizing the traffic signs research in china and abroad, andanalyzing the shortcomings of previous related studies. Then put forward the researchdirection and method. In this paper, test method was adopted to do the research onvisual cognition safety of highway traffic signs.Secondly, visual cognition test of traffic signs were carried out in simulation barnand real road. By contrasted the different character height and visual cognitiondistance, we concluded that the magnification is2.7. we developed time loggingsoftware to measure the drivers’ visual cognition time, and used the eye tracker torecord the eye movement parameters (fixation duration and fixation number) and thedriving simulation barn recorded the vehicle running state(acceleration and offset).Thirdly, the research of gaze behavior when driver reading the traffic signs. Thispaper adopted dynamic clustering method to divide the drivers’ gaze region into threecategories, namely, traffic sign region (the first area), the road ahead region (thesecond area), the car dashboard region (the third area). Through the analysis of eyemovement data we can concluded that as the driving speed and information volumeincreased, the fixation duration and number percentage of traffic sign region had adecreasing trend and the fixation to the front road decreased. Beside these, the visualcognition time decreased as the driving speed increased. Fourthly, the research of vehicle running status changes when driver reading thetraffic signs. Through the analysis we can concluded that information volume anddriving speed have a high correlation with the acceleration and offset distance ofvehicle. With the information volume and driving speed increased, the vehicleacceleration change and standard deviation of acceleration have shown an increasingtrend, the vehicle offset distance and standard deviation have same changing trend.From the prospect of drivers’ visual cognition safety, the number of road name onhighway guide signs should not exceed5, and to the non-guide signs it needs specificanalysis on the complexity of the graphic symbols, but overall, it should not exceedthe maximum amount of information of guide signs.Main findings were summarized at the end of the paper. Directions for futureresearch in this topic were proposed.