Research On The Visual Characteristics Of Elderly Drivers In Complex Traffic Information Situations

With the constant development of society and an increasingly growing number of elderly drivers,the annual traffic accidents related to the elderly drivers are increasing year by year.The human factor is the main cause of traffic accidents,and the human perception factor plays a leading role in the human factor,the traffic information that obtained from driver’s visual system accounts for about 90%of the total information.The study on the visual characteristics of the elderly driver can be helpful for revealing the law of eye movement of the elderly driver at the intersection,which is of great theoretical significance for the evaluation of the driving ability of the elderly driver.The visual characteristics of elderly drivers at the urban road intersection was taken as the starting point,based on the KMRTDS driving simulator system platform,38 drivers of different age groups were recruited and the eye tracker was used to record dynamic eye movement data(e.g.,the fixation time,fixation frequency,saccade amplitude,scanning speed,etc.)of the approach and entrance the intersection.The results are as follows:First,the drivers’ gaze point video was analyzed,and the K was set to be 5,as well as the K-means clustering algorithm was used to cluster the coordinates of the drivers’ fixation point,and then the drivers’ gaze point was projected to the plane and the distribution of the fixation point was obtained.According to the clustering results and the distribution of the fixation point,driver’s visual plane was divided into the five regions(i.e.,lane region right ahead,left lane region,right lane region,speedometer and the upper right sign region).In the next place,according to the results of the field plan,the difference of the fixation time between the elderly and the young and middle-aged drivers in the different time periods at the intersection was analyzed,and the significance analysis was carried out.The study found there is a big difference that the two groups of drivers’ eye movement regularity near the intersection,young and middle-aged driver’s gaze distribution is more uniform,to take into account the traffic conditions around the lane area,but older drivers at the intersection focus on a certain area.At the same time,the duration of the gaze duration,saccade amplitude,and the scanning average speed of the two groups of drivers are very different.The older driver takes more time to get enough information while entering the intersection.Meanwhile,the saccade amplitude and the scanning average speed lower than the young driver.Finally,the Markov chain theory is used to characterize the driver’s gaze transition mode,and the probability of transfer of the two groups in each gaze interval is solved respectively.The comparative analysis found that young and middle-aged drivers had a more flexible gaze transition mode,while older drivers were more likely to observe the same area in order to obtain adequate traffic information.