Citation

McDonald LB, Ellis NC. Transp. Res. Rec. 1975; 530: 18-30.

Copyright

(Copyright © 1975, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The need exists for a method by which a highway designer can determine, during the design stage, whether a highway design will demand so much of a driver's attention that there is insufficient time to look for and avoid accidents. One aspect of attentional demand is tracking the lane in curves and tangent sections. A study was done to determine (by use of a secondary task) what percentage of a driver's attention is required to track a lane while various curves are negotiated at various speeds. In addition, data were gathered about how drivers control their lane position.

RESULTS indicated that lane tracking in a 17-deg turn demanded 26 percent of the subject's attention at 20 mph (32 km/h) and 42 percent at 40 mph (64 km/h) and that attentional demand in the straightaway remained around 23 percent for speeds from 40 to 80 mph (64 to 129 km/h). Lane-tracking data indicated that the median location was 5 in. (12 cm) to the left of the lane center in straightaways, 7 in. (18 cm) to the left in left turns, and 6 in. (15 cm) to the right in right turns. Distributions of drift distances from these three median locations were also determined.