LBS-Based Dilemma Zone Warning System at Signalized Intersection

Abstract

In the field of traffic engineering, drivers’ confusion during yellow interval is a great danger to traffic safety. To help drivers solve such problem, an LBS-based dilemma zone warning system at signalized intersection is designed. Different from other dilemma zone solving systems, this is an active safety system, which makes it possible to help drivers take active actions according to reliable warnings. An algorithm based on data from Differential Global Positioning System (DGPS) and traffic signal detector (TSD) was built in the single-chip microcomputer of Dedicated Short Range Communication (DSRC). Corresponding voice warnings (“stop” or “go”) would be sent to drivers by on-board voice alerter. Besides, communication delay and drivers’ reaction time were taken into consideration in the design of warning areas ahead of dilemma zone. To reveal characteristics of reaction time, a field test has been conducted and the reaction time is shorter than current standard. When vehicles are detected in different warning areas, drivers would get alarmed at the beginning of yellow interval. Moreover, this system has been verified feasible in theory by a case study at signalized intersection.