Study On Limiting Information Content And Maximal Prefix Distance Of Traffic Guide Sign

As China’s urbanization is speeding up, the city traffic network is increasingly developed and the city road is more and more perplexing. The traffic signs guiding, restricting, warning or instructing information to the drivers are one of the main facilities. As a result, its proper design and installation has large effect on the city traffic. This paper studied the maximum amount of information and the maximum prepositive distance of traffic signs through the indoor simulation experiment method by using dynamic video stimulation.First, programming with E-Prime software, simulate the process of divers searching for the target road name on the traffic sign through the indoor simulation experiment. And study the effects of the number of road names and its word count on the searching reaction time. The results show that the number of the road names and the word count have significant influence on the reaction time, but the degree of difficulty of search task does not increase with the word count of road names.So the name number is a better index to measure the amount of information of traffic sign than the word count.Second, the author using eye tracking system though the indoor simulation experiment, discussed multiple eye movement indices such as the reaction time, total fixation time, fixation frequency, average fixation duration, pupil size. Result shows that the maximum road name number of the traffic sign is6at most. Comparing the eye movement indices in different regions and different position of target road name on the traffic signs, the author found that left and the above part of the traffic signs gained more attention than the right part, which indicates that the target road name searching process is influenced by the top-to-bottom and left-to-right daily reading habits.Finally, Marking the6road names as the objects of study, through the indoor simulation experiment based on driver’s short-term memory, the author found that the memory interval time has a significant effect on the reaction time and accuracy. While the target road name position has no such effect. And the indices of reaction time of target road name in different position and different interval time didn’t show a certain regularity. It is concluded that the memory time should not be more than25seconds. And the calculation of the maximum recommended value of the prepositive distance of traffic signs on road with different speed limit is possible according to the findings of this study.