Bicycle detection through the use of inductance loop detectors at vehicular actuated traffic signals

In the United States the bicycle continues to increase in importance as a transport mode for a growing number of people. However, due to significant differences in physical size, mass and operational speed when compared with motorized vehicles, this increase in bicycle traffic has led to a number of relatively new traffic engineering problems. One problem that frequently occurs involves bicyclists that attempt to pass through intersections controlled by vehicular actuated traffic signals. The proper operation of a vehicular actuated traffic signal depends on in-road sensing devices that detect vehicle presence and/or passage. Proper detector operation is, however, frequently precluded because of the small mass and size of bicycles. The most popular type of in-road sensing device in use today is the inductance loop detector. As the bicycle continues to increase in importance as a transport mode for a growing number of people, the detection of bicycles through the use of inductance loop detectors at vehicular actuated traffic signals also continues to increase in importance. This report presents a review of research that has been previously conducted on this topic, a discussion of a field testing program for evaluation of the bicycle detection capability of typical loop detector installations and an analysis of the data that was collected in the field testing program. Conclusions and recommendations based upon the theoretical and experimental study of the performance of inductance loop detectors in detecting bicycles are also suggested. This report should assist engineers and technicians in the design of inductance loop detector systems that provide dependable and consistent bicycle detection at vehicular actuated traffic signals