Authorities who installed Los Angeles' first so-called "smart" crosswalk here last March said Thursday the high-tech system has reduced traffic speeds and protected pedestrians.
Despite its success, however, the technology still has a couple of kinks.
"We have done a little before and after study," said Brian Gallagher, a city transportation engineer.
Microwave sensors installed at Lankershim Boulevard and Arminta Street--which previously had no traffic lights--trigger a flashing yellow signal to warn motorists of pedestrians. The sensors send out beams that when disturbed by pedestrians cause the lights to flash.
"There was a big improvement in the percentage of drivers that yield the right of way," Gallagher said. Before the lights, 80% of the cars that had a reasonable amount of time and distance to stop did not do so. That rate fell to 65% after the installation, he said.
Also, before the system was in place, most motorists usually traveled between 27 and 29 mph through the intersection. Now most vehicles pass through at a speed usually between 21 and 27 mph, Gallagher said.
His follow-up study found the sensors have a 95% success rate, only misfiring 5% of the time.
Sometimes, when automobiles in the westbound lane of Arminta turn north onto Lankershim, the sensors mistake the cars for people. And the sensors do not detect pedestrians who cross outside crosswalk boundaries.
Last October, before the sensors, Juana de la Cruz Mercado and her infant daughter were struck by a sports utility vehicle at the intersection. They have since recovered.
After the accident, Los Angeles police officers had planned to question fellow Officer Bryce Wicks in connection with the hit-and-run incident. But shortly after they arrived at his Acton home, Wicks shot and killed himself.