The Research In Prepositive Distance Of Advanced Intersection Lane Control Signs

As an important section of the traffic guide signs in urban road intersection, advanced intersection lane control signs(AILCS) is indispensable for drivers to recognize and comprehend effective destination information. A rational installment of AILCS make a positive influence on the safety and efficiency of the urban road intersections. Based on the multi-subject theory in the traffic engineering, cognitive psychology and ergonomics, this research has investigated the different design types of AILCS, which focuses on the shortages in the AILCS design and installment. The reasonable information load threshold of AILCS is determined by the theoretical analysis and computer-based experiments. Based on the proposal, the recognizing process of traffic signs information transmission is further analyzed in this paper. The main research contents are listed as followed.Investigation of the information load threshold in integrated signs with AILCS and destination signs(DS).A two-step experiment is conducted in this study. The step one is a legibility experiment of single lane control arrow signs is conducted. It is found that there is no significant difference between drivers’ reaction time in different types of single lane control arrow signs, which is a guidance for the integrated signs design. Then, the step two is a legibility experiment of integrated signs, which to get a cognitive rule in integrated signs. In addition, the information load threshold of integrated signs is determined by analyzing the mutation point of drivers’ reaction time.Recommendations for the installment and design of the integrated signs with AILCS and DS.An equivalence principle is proposed based on the former studies and the computerbased legibility experiments. Recommendations of total street names and lane control arrow number is made according to the different type of central pattern. In addition, it is suggested not to set an integrated signs which have exceed the information load threshold.Field verification experiment of AILCS.A relationship between three types of AILCS in simulated computer-based experiments is investigated, which is based on the statistical analysis from the distance-reaction in field experiments. The field experiment results are in accordance with those in the simulated computer-based experiments, which have verified the validity of the simulated experiments. Thus, under the same condition, it can be proved that the simulated experiments based on psychological experiment design platform called EPrime meet the statistical requirement in legibility experiment of traffic signs, which have guaranteed the accuracy and science of the visibility of traffic signs.Model construction of prepositive distance in AILCS and application in examples.Based on the cognitive psychology and ergonomics, this study analyzes the process of drivers’ recognizing, comprehending and operating behaviors in traffic signs. Model of prepositive distance in AILCS is constructed, which is consisted of the combined installment and separated installment. In addition, the prepositive distance in AILCS is determined by the application of the model in example.Findings in this study will provide rationale for urban highway in designing and installment of traffic guide signs, which is a theoretical basis for revising the Chinese national standard GB 5768-2009, Road Traffic Signs and Markings.