The Utah Department of Transportation is finding success using SmartSensor Advance for dilemma zone protection at pedestrian crossings.
Jamie Mackey, PE, PTOE, statewide signal engineer at UDOT, says that running signals in coordination can sometimes delay pedestrians unnecessarily. The problem is, if there are gaps in traffic, pedestrians will often dart across the road without waiting for a walk sign. On the other hand, running the signal free but without detection means that a single pedestrian could interrupt the progression of many vehicles.
It occurred to Mackey that SmartSensor Advance or SmartSensor Matrix could conceivably solve both problems. With Advance detecting traffic at a crossing, Mackey found that pedestrians can cross immediately when no cars are present; but if vehicles are detected approaching the stop bar, Advance can signal the controller to extend the green light to let those vehicles pass, so that traffic isn’t stopped at a moment when pedestrians wouldn’t risk crossing the street anyway.
SmartSensor Advance detects if there are vehicles in the dilemma zone adjacent to the crosswalk and will prevent the walk indicator from flashing if cars are going too fast.
“This is done to prevent people from just hitting the button and strolling across the street when the cars on the street are traveling at 40 or more miles per hour,” says Spencer Banta, marketing manager at Wavetronix.