The purpose of the present study was to examine effects of driver, vehicle, and environment characteristics on Collision Warning System (CWS) design. One hypothesis was that the capability of collision avoidance should not be the same since the driver, vehicle, and environment group have different characteristics. Accident analysis and quantitative analysis was used to examine this hypothesis in terms of 'risk' and 'safety margin' respectively. The study focused on rear-end collisions. The accident analysis showed that heavy trucks showed a higher susceptibility for fatal rear-end accidents than car and light truck. Also, dry road surface compared to wet or snow, darkness compared to daylight, straight road compared to curved road, level road compared to slope, crest or sag, roadway having more than 5 travel lanes compared to roadway having 2, 3 or 4 travel lanes showed a higher susceptibility of the fatal rear-end accidents. Relative rear-end accident proportion compared to the other types of collision was used as a measure of susceptibility. As a result of quantitative analysis, a significant difference in terms of Required Minimum Warning Distance (RMWD) was made among different vehicle types and braking system groups. However, relatively small difference was made among different ages or gender groups in terms of RMWD. Based on the result, breaking performance of vehicle should be regarded as an input variable in the design of CWS, specifically warning timing criteria. The report is available at the Internet: http://www.ep.liu.se/exjobb/itn/2001/kts/017/exjobb.pdf.
Abstract