Remote Sensing (LIDAR) for Management of Highway Assets for Safety, 2003

The main objective of this study was to utilize light detection and ranging (LIDAR) technology to obtain highway safety-related information. The safety needs of older drivers in terms of prolonged reaction times were taken into consideration. The tasks undertaken in this study were (1) identification of crashes that older drivers are more likely to be involved in, (2) identification of highway geometric features that are important in such crashes, (3) utilization of LIDAR data for obtaining information on the identified highway geometric features, and (4) assessment of the feasibility of using LIDAR data for such applications. A review of previous research indicated that older drivers have difficulty negotiating intersections, and it was recognized that intersection sight triangles were critical to safe intersection negotiation. LIDAR data were utilized to obtain information on potential sight distance obstructions at six selected intersections located on the Iowa Highway 1 corridor by conducting in-office line-of-sight analysis. Crash frequency, older driver involvement, and data availability were considerations in the selection of the six intersections. Results of the in-office analysis were then validated by visiting the intersections in the field. Sixty-six potential sight distance obstructions were identified by the line-of-sight analysis, out of which 62 (89.8%) were confirmed while four (5.8%) were not confirmed by the video. At least three (4.4%) potential sight distance obstructions were discovered in the video that were not detected by the line-of-sight analysis. The intersection with the highest crash frequency involving older drivers was correctly found to have obstructions located within the intersection sight triangles. Based on research results, it is concluded that LIDAR data can be utilized for identifying potential sight distance obstructions at intersections. The safety of older drivers can be enhanced by locating and rectifying intersections with obstructions in sight triangles