Research On Inform Signs Of Grade Intersection Based On Driver’s Visual Characteristics

Urban road traffic is the most important basic setting to support urban vitality.In 2017,the National People’s Congress proposed the overall requirement that “urban management should be as elaborate as embroidery”.As the "language" of road traffic,the regulation and reasonable traffic sign setting is an important embodiment of the fine management of urban traffic.The Directional Sign is a type of traffic sign that includes forenotice,inform,and confirmation signs.At present,there are few related studies on the setting of inform signs in China.The current national norms only give general requirements for setting standards for inform signs.There are no specific descriptions for different road conditions,which leads to many problems in the setting of inform signs in some cities.The most prominent is that the setting position is not standardized.Normally placed on the right side of the road,it is often placed on the left side when the road is marked with a central isolation belt.Therefore,it is necessary to study the problem of setting the inform signs at the intersection.In this paper,the status quo of the inform sign setting at the intersection is taken as the research background.Combined with the visual characteristics of the driver,the indoor experiment method is used to study the position of the inform signs.The influencing factors include the number of lanes and the lane position.The driver’s cognitive time is obtained by E-Prime software,and the eye movement index such as pupil diameter,cumulative gaze time,saccade duration,visual information search trajectory and gaze hot spot are collected by ETG eye tracker,and different visual characteristic parameters are performed.After the analysis,the setting scheme of the grade crossing inform signs is obtained.The experimental results show that the interaction between the position of the inform signs and the number of lanes is significant(P<0.05),but the interaction with the location of the lane does not have a significant impact on the eye movement parameters(P>0.05);In the four lane conditions,the inform sign is set on the right side to reduce the driver’s cognitive load and improve reading efficiency.In the three-lane and five-lane conditions,when the notification flag is set on the left side,the driver’s cognitive load,information processing difficulty is lower,and the reading efficiency is higher;when the driver is in the inner(outer)side lane and the inform sign is set at the same side of the road,there will be no backsight phenomenon and the gaze point is simple and the degree of dispersion is low.The position of the inform sign has little influence on the driver’s reading process.When the driver is in the inner(outer)side lane and the inform sign is set on the other side of the road,the position of the notice sign has a great influence on the driver’s reading process,which is manifested in the retrospective phenomenon caused by the visual information search trajectory,the track of gaze point trajectory is highly discrete,and the focus on hot spots area is scattered.The research conclusions enrich the research on the setting of the inform sign at the intersection,which provides a reference for the further refinement of the current national regulations.At the same time,it is also of practical significance in giving better play to the function of inform signs,ensuring good traffic conditions and improving the efficiency of intersections.