Driver's Trajectory Tracking Model in Curves of Two-Lane Highway

Considering the complexity of horizontal alignment in curves, and the uncertainty of steering behavior resulting from drivers' fuzzy perception and subjective tendency, the control factors of steering behavior were introduced by analyzing drivers' driving characteristics which are influenced by road alignments ahead. The multi-objective fuzzy optimization decision theory was used to study the influence of fuzziness and subjectivity on steering behavior. Then a mathematical method for modeling driver's trajectory tracking behavior was established using the weight determination method that is based on the gray theory and combines subjectivity with objectivity together. In addition, field experiments in five curves were carried out, and the modeling method was verified to be feasible by comparison of experimental and simulation values in trajectory curves. The results show that the length of trajectory, lateral force coefficient, trajectory's lateral offset are control factors of trajectory tracking behavior; and driver's subjective characteristics in fuzzy optimal decision making trajectory tracking behavior can be reflected by the weight determination method combing subjectivity and objectivity.