New technology helps bicyclists at traffic signals

By Robbie Webber

A new enhancement to a bicycle detection and counting device solves a problem and improves safety for bicyclists at intersections. The new addition to the Iteris Smartcycle technology allows bicyclists waiting at a red light to be sure they have been detected, that the light will change, and that the green light will be sufficiently long for them to finish crossing the intersection.

Bicyclists waiting at a traffic signal may wonder, “Is the light going to change? Do I have to wait here until a car comes along? Should I run over to the pedestrian button, just to be sure I get a green? Or maybe I should just wait for a gap in traffic and run the red.” In addition to the uncertainty of whether and when the light will change, the green that finally comes may not be long enough to allow bicyclists to cross the intersection safely.

Unreliable bicycle detection at traffic signals causes safety problems for bicyclists and may contribute to the perception of bicyclists as scofflaws. It also causes excessive delay, which is irritating to anyone. If a green will never come, running a red light makes sense, although it is illegal in most states and potentially dangerous. Bicyclists that opt to use the pedestrian button face problems as well. They likely have to dismount in the street so they can reach the curb and the sidewalk-mounted pedestrian button. After activating the pedestrian signal, they are in a poor position to navigate the intersection when the green signal comes. They may now be on the sidewalk or near the curb, putting them in danger of being cut off by a right-turning car.

Properly calibrated detectors in the pavement or overhead can pick up bicyclists, and many cities include pavement markings on popular bike routes that indicate where a bicyclist should wait to assure detection. But there are still many intersections where a bicyclist is at the mercy of a larger vehicle coming along to trigger the signal. In addition, even at intersections with correctly installed detectors, bicyclists may not know if they have been detected.

This is where the new addition to the SmartCycle technology comes in. A light allows bicyclists to know that they can expect a green, and the light will be long enough to cross the intersection. This is an enhancement to their existing system that detects bicycles at intersections—both those in bike lanes and those in mixed traffic—and also counts bicycles.

This technology follows the recommendations outlined in an ITE Journal article that noted a “blue light feedback device” improved bicyclists’ dwelling behavior at intersections with pavement markings. As more people take to bicycling for transportation, improvements such as these will be important for both signal compliance and safety.

Robbie Webber is a Senior Associate at SSTI.