The Experimantal Study Of Drivers’ Cognitice Process Of Visual Information For Traffic Signs

Nowadays with the rapid development of transportation system, the trafficaccidents are leading more huge social harm. The scientists of the world are still seekingthe cause of the problem and solution. According to the current research, the reason oftraffic accidents are various, but all of them are related to the driver’s improperoperation. If the driver has enough information, there will be enough time for theirdecision and response. Therefore, to provide enough information to the driver is aneffective way for avoiding the accidents or reduce the damage in accident.Traffic signs is one of the important measures for preventing traffic accidents. Itsadvantages are effectively, easy implementation and low cost. However, with the trafficenvironment become more and more complex, the researchers found that in many areas,the traffic signs’ utility is decrease. The reason is that the traffic signs’ ability rely onthe drivers to understand its meaning and than make dicision. In addition, there aremany factors can influence the drivers’ cognition, including regional, cultural,education, age and gender, etc. Thus, it should consider these factors when design orset the traffic signs.At the present, the drivers’ physiological and psychological demand are becamethe emphasis of the traffic signs’ study. Based on the cognitive theory, this paper justbuild a model to describe the drivers’ cognitive process of the traffic signs. In the study,the simulator experiment was employed to test the drivers’ behavior under differentconditions. To analysis the difference of driving behavior, eye movement and eeg data,we acquired the drivers’ cognitive characteristic, and verified the model. According tothe results of experiment data, this paper get the following conclusion:(1) When the driver performing the "curve-deceleration" strategy, the judgmentonly depends on the information about the curve, but careless to the informationprovider. And different objects can provide curve information, and these informationcan be superposed to improve the confidence value of curve information, and then makethe driver releasing the accelerator earlier.(2) During the experiment, we found that when traffic signs in the driver’s field ofvision, the driver’s30%eye fixation would be distracted away from the road byobtaining the information on the traffic signs. In addition, we found that when the trafficsigns and road line type provide the same information, the driver’s eye fixation on thetraffic sign would be shorten.(3) The drivers’ P300waves show that when setting the traffic sign near the curve, the latency of P300component is earlier than without traffic signs. And compared thedriver’s response time and error rate, we also found the drivers’ performance in thegroup with the traffic sign is better than the group without traffic sign. These can explainthat the traffic sign effectively shorten the driver’s information transformation process.(4) The driver’s information matching process is actually a process of giving eachobject an information and weighted summation. This information is not only influencedby objects, but also affected by the driver’s learning and memory system. Thus, theposition of traffic signs, bend radius and driving time all influence the process ofinformation acquiring. In the experiments, when the traffic sign setting near the curve,the first position of driver releasing the accelerator pedal is positive with the bend radius;however when traffic sign setting far from the curve, the first position of driverreleasing the accelerator pedal is positive with the position of traffic sign. Moreover,the increase of number of driving will lead the first position of driver releasing theaccelerator pedal increasing.In all, the speed driver’s response to curver information decides the curve drivingsafety. To reduce information transition time and acquire the information in advanceare the guarantee of the drive to make appropriate operation. Through the experimentalstudy on drivers’ visual information cognition process, this reaserach effectively get thedriver’s visual perception characteristics of traffic signs. According to thesecharacteristics, the advantage of the traffic sign is the ability to quickly and efficientlyprovide the information of ahead road. But early to set up traffic signs not only cangreatly reduce the driver’s attention about the actual road, and also increase the trafficsign’s transition time. Those will cause the driver to ignore the risk factors of aheadroad. So when setting traffic signs, it need more consideration about the driver’scognitive characteristics to the maximum the role of the traffic signs.