Optimization Method of Comb-Shaped Speed Reduction Marking Spacing Based on Variable Space-Time Frequencies

摘要

In view of the practical matters that drivers often have traffic accidents on the freeway curves because of speeding, it is essential to improve the traffic security level and reduce the traffic accident rate of highway. And the key aspects are to keep a safe running speed or let the speed down by setting up reduction measures like speed reduction marking. This paper presents a more scientific design scheme of speed reduction markings. Taking comb-shaped speed reduction marking for example, it's spacing were optimized for further research. First, this paper gives explanations on mechanism of the space-time frequency influence on the drivers' perception of vehicle speed from the angle of body sensing (mainly visual sense). Second, a mathematical model to describe the relationship between spatial frequency and spacing of speed reduction marking was established. After defining comfortable acceleration, maximum safe speed, etc. aiming at different freeway curves, the model can obtain specific value of speed reduction marking's spacing. At last, to explore the practical effects on drivers' speed perceptions, this study simulates highway scenes by 3Dmax. Those road surfaces are patterned with speed reduction markings set in different space-time frequencies. And then evaluates the deceleration effects of those speed reduction markings by comparative analyzing experimentalists' reactions recorded. The experimental results shows that the deceleration effect can be improved effectively by decreasing the spacing of speed reduction markings, namely increasing the frequency. In addition, variable space-time frequencies give drivers illusions that the running speed keeps changing. In general, speed reduction markings set in variable space-time frequencies have better effects on speed reduction.