| Title |
The Effect of Road-obstacle Luminance Combination at Night in Positive Contrast Condition on Driver's Obstacle Detecting Distance : Road Driving Test by the Driver in Their 60s or Older |
| DOI |
http://dx.doi.org/10.5207/JIEIE.2018.32.12.033 |
| Keywords |
Road Lighting ; Visibility Concept ; Small Target Visibility ; STV ; Stopping Sight Distance |
| Abstract |
This is the basic study to develop visibility-based road safety evaluation approach at night, which is intended to identify the effect of road-obstacle luminance combination at night in positive contrast condition in which the obstacle is brighter than road surface on driver's obstacle detecting distance at night as well as to evaluate the safety level on the road at night. To that end, road driving test by the drivers in their 60s was conducted at night. Road luminance was set at 0.3, 1.6 and 3.0cd/m2, respectively, for the test while obstacle luminance was set at 4 to 5 different conditions depending on road luminance to provide positive contrast condition. The size of the obstacle was set at 15×15 according to the requirement in domestic road design criteria. According to the test result, the lower the road luminance and higher the obstacle luminance the longer the detection distance, indicating the relatively higher algebraic function relationship. In this study, combination relations between road luminance and obstacle luminance required for the driver to detect the obstacle at stopping sight distance were presented by target safety level and the result is expected to be used as road safety evaluation guideline at night to determine the obstacle luminance necessary to achieve the safety goal at the certain road luminance condition or as guideline to determine the nighttime road safety evaluation using road luminance and obstacle luminance. |