The Mechanism Research Of Illumination Variation’s Influence On Drivers’ Recognition Time Under Dynamic Circumstances

With the rapid increase of car ownership, the road traffic accident rate is high, and the problem of road traffic safety is more and more serious. At dusk and dawn when illumination rapidly changes, there is a high rate of traffic accident, which has caused great concern, but the related research and the accident mechanism achievements are penurious. The drivers’visual characteristics are greatly influenced by speed and illumination; when illumination changes quickly, the time of drivers’target recognition is volatile. Recognition time has an impact on drivers’ decision and judgment, and then affects the driving behavior and driving safety. This article firstly explores the rule of the drivers’ recognition time to target boards with different colors, then identifies the relationship between recognition time and speed as well as illumination, finally makes clear the stopping sight distances and limited road speeds under different driving speeds and road illumination ranges. It is significant for reducing accident rate.This article is based on the fund project of "The Mechanism Research of Road Flow Characteristics and Influence on Traffic Safety Based on Illumination (No.51308177) ". Firstly, a real vehicle experiment is designed to explore the rule of drivers’recognition time to target boards with different colors under different driving speeds and illumination intensities. Secondly, analysis of variance (ANOVA) is used to analyze whether colors have a significant impact on drivers’recognition time under different driving speeds and illumination intensities. Thirdly, nonlinear regression is applied to develop the models of drivers’recognition time and illumination and the models of drivers’ recognition time and driving speed, and by optimizing the traditional model of stopping sight distance, recommended stopping sight distances under different driving speeds and road illumination ranges are calculated. Finally, after combining recognition time with driving speed model, stopping sight distance model and design specifications for highway alignment, the limited driving speeds of roads designed for different speeds under different illumination intensities are deduced. The results show that, target boards with different colors have different statistical significances on drivers’ notice and discern moments and their recognition time; under the condition of the same driving speed, there is a high fitting degree between recognition time and illumination models, the significance meets the mathematical requirement, and the model is accurate; compared with the traditional model, the stopping sight distance of the optimized model is more advantageous for the road traffic safety; the measure of using different limited driving speeds to reduce accident rate at dusk is direct and executable, and the dynamic management of speed based on illumination variation can be realized.