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Inside LA's Super Cool Traffic Light Control System

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Remember in the remake of the Italian Job, when Seth Green's character manipulates traffic signals to create an escape route? That's totally possible in LA these days, but you're more likely to see it used to get a bunch of limos to the Oscars smoothly. All this cinematic possibility is offered by the city of Los Angeles' Automated Traffic Surveillance and Control system, which links up traffic data, signal timing, and live video to keep things moving on LA's streets, as explained by Forbes in a story out yesterday. In addition to detailing the God-like powers of the ATSAC, the article gives a nod to LA's efforts to expand its public transit and bicycle infrastructures, since the system has to be able to accommodate everyone. The ATSAC is expected to be complete by early 2013.

Here's a little bit about how the ATSAC work and why it matters to your LA traffic woes:

Regarding the ATSAC infrastructure
- Los Angeles was the first US city to centrally control traffic lights--during the 1984 Olympics it rewired intersections near the Coliseum
- "18,000 magnetic sensors embedded in Los Angeles' roadways send traffic speed and congestion levels to a control room in a former emergency bunker four stories beneath a City Hall annex in downtown Los Angeles."
- ATSAC has 400 live traffic cameras "installed at the most troublesome spots"
- The cost to integrate an intersection into the system is about $150,000
- The system is built on the fiberoptic network; wireless proved impossible, even for Hughes Aircraft
- The city charges $75,000 for license to the software package
- Los Angeles has sold ATSAC to Long Beach and Gilroy, and it is pitching it to Washington, DC
- Several studies have found that travel times drop 15% near ATSAC signals, and drivers make 20% to 30% fewer stops

Regarding the ATSAC/Seth Green Connection
- The system is adaptive: "As congestion builds on one street relative to another, it adjusts traffic-light cycles to give more green time to the congested lanes."
- LA's "187 miles of bike lanes and 18 miles of bus-only lanes" have priority
- ATSAC knows when buses are running late and extends green lights for them (buses have to wait in traffic when they're ahead of schedule)
- ATSAC has special cycles in Jewish neighborhoods so that observant Jews don't have to push a traffic signal button on the Sabbath
- There are special cycles for pre-Lakers game traffic, and "ATSAC guides limos to the Academy Awards"
· 4,114 Stoplights in Los Angeles and the Intricate Network that Keeps Traffic Moving [Forbes]