Influence of Installation Height and Angle of Single-Post Nonstop Sign on the Driver’s Fixation Characteristics

• Published in: Journal of highway and transportation research and development 2023-06, Vol.17 (2), p.39-47
• Main Authors: Li, Na, Ou, Li-yun, Chen, Qing-lan, Wang, Yi-mo
• Format: Article
• Language: English
• Subjects: Eye movements; Factor analysis; Fixation; Homogeneity; Influence; Outliers (statistics); Roads; Simulation; Traffic signs; Virtual reality
• ISSN: 2095-6215; 2095-6215
• DOI: 10.1061/JHTRCQ.0000866

To explore the influence of installation height and angle of traffic signs and their interaction on the driver’s fixation characteristics within the recommended range of national standards and selecting the common nonstop sign on an urban road as the test sign, a simulated driving scenario of a two-way four-lane urban road was built using the virtual reality software UC-win/Road 10.0 and the driving simulator FORUNM 8, and 32 drivers were selected as the subjects for the eye movement test. Through the simulation test of sign recognition in the simulated cockpit with the driver wearing an eye tracker, the indicator data (fixation duration, number of fixations, and time of first fixation) of the driver recognizing the stop sign with different combinations of height and angle of the traffic signs were obtained. After preprocessing the data, such as outlier elimination, residual normality, and variance homogeneity test, the influence of height, angle, and their interaction on the above indicators was analyzed using the two-factor ANOVA method with interactive effects. The result shows that (1) in single-factor analysis, different installation angles only have a significant influence on fixation duration, and the fixation duration caused by the positive installation is higher than that caused by tilt angle; (2) there are no significant differences in the influences of different installation heights on the driver’s fixation duration, number of fixations, and time of first fixation; and (3) the interaction of installation height and angle has a significant influence on the driver’s fixation duration and number of fixations. Among the 4 combinations of height (high and low) and angle (positive and oblique), the fixation duration and the number of fixations caused by “high × positive” are much higher than those of other combinations, showing that the nonstop sign installed by this combination can attract the most interest and attention of drivers. It is recommended to install this nonstop sign on the two-way four-lane urban road.