A Study On The Impact Of Lighting On Driver Visual Perception Characteristics At Highway Intersections

Considering economic benefits and Stroboscopic effect,some highways in China do not provide lighting.On rural highways,when pedestrian flow and vehicle flow join at unsignalized intersections,severe accidents occur between vehicles and bicycles,or vehicles and pedestrians,due to lack of lighting at night.Appropriate lighting and speed limits should be set at such intersections according to the visual perception characteristics of drivers to improve traffic safety and protect life and property.This paper studies the visual perception characteristics under different speed at night highway intersections.We summarized the relevant domestic and foreign research,and qualitatively divides the highway intersection lighting area into transition area with significant lighting changes and normal area.In the transition area,we analyzed the driver’s pupil diameter changes under different lighting and speed through real-vehicle road tests;in the normal area,we use the simulator test to study the driver’s visual search capability for emergencies under different lighting and speed,combined with attention distribution theory and logistics regression to quantify the driver’s visual search capability,the specific research content is as follows:(1)First,we analyzed the components of the traffic scene at the highway intersection,and selected the typical intersection as the research object.Then we analyzed the safe stopping distance at the intersection,summarized the current vehicle headlight standards and road lighting specifications,determined the necessity of street lighting layout,and provided a basis for scene selection and construction for subsequent tests.Finally,we divided intersections into areas qualitatively according to the lighting characteristics.We also determined the research parameters and methods of each area.(2)We analyzed the visual perception characteristics of drivers in the transition area,designed and completed the road test for the transition area,using the pupil diameter.We preprocessed the test data and extracted the required parameters,then analyzed and compared the transition area lighting and speed limit schemes,and found that setting the transition section driver’s pupil diameter is significantly better than not setting it.(3)We analyzed the visual perception characteristics of drivers at intersections,and choose attention distribution theory to study the visual search capabilities of drivers at intersections.We built a test platform to collect test data and performed statistical analysis on the extracted parameters,combining it with logistics regression to build a quantitative model of visual search capabilities based on attention allocation theory.Comparing intersection lighting and speed limit schemes through vehicle operating parameters and visual search capabilities,we found that setting up lighting is a necessary measure to ensure traffic safety at highway intersections.Based on lighting,lowering the speed limit is effective in improving the driver’s visual search ability.