Approach And Application Of Steering On Freeway Curve Based On Visual Edge Rate

Curves are the main sections where traffic accidents take place. While in a variety of factors causing road traffic accidents, human is the main cause. Visual information accounted for the main part of the environmental information that human received. So it is important to take reasonable and scientific measures based on drivers'visual information to improve the track of vehicles at the curves, and to improve the traffic safety level.Firstly, the study conducts a comprehensive comparative analysis of current steering approach at curves, and then researches the distribution of drivers'attention in straight road and curves. The results shows that, when drivers driving in a straight road, Most of the attention distribute on the road; before drivers entering curves, the drivers will search the tangent point of the curves; when driving in the curves, their attentions will be concentrated close to the tangent point in the direction of curve shifted; while pasting some edge markings next the road edge line, these markings will shift part of the driver's attention.Base on the analysis of drivers'visual information characteristics in the curves and driving characteristics, the study proposes steering approach at curves based on visual information and establishes the model combined with the existing steering method.Based on the models, experimental sections are chose on some dangerous sections of Shi Man freeway. Some designed edge markings with different frequencies are pasted on different regions of a straight road, and vehicles'speed of the road before and after the experiment are observed and noted. The result shows that at the straight road in front of the curve, when the frequency is 4Hz in adaptation area, frequency in controlling zone is changed from 4Hz to10Hz, and the frequency is 10Hz in the transition zone, the vehicles'speed are controlled most obvious, the average speed of cars which is speeding before experiment changed from the 88.04Km/h down to 80.65Km/h.After the speed control experiment in straight road, in the four different experiments which contain 7 small groups experiments related with steering on the transition curve, we set different frequency values and form edge markings on left and right of the lane. The result of vehicle lane keeping in the curves shows that, when the vehicle in the traveling lane whose left edge marking frequency is 5Hz, and the right side is 10Hz, the effect of lane keeping is the most obvious; when the left edge markings are straight, while the right edge markings are fishbone-shaped, lane keeping effect is the most obvious.Based on the result of speed control experimental on straight road and lanes keeping experimental on curve road, road alignment data and related observed variables during the experiment, Weber fraction in the model of speed controlling and the parameter about lateral migration velocity and the frequency difference in steering model are calibrated.Finally, the study makes a conclusion for the theory and the experimental results, and proposes the contents of further study.