I live in the Bay Area and drive to work on 101. On the freeway, I pass "signs" that give you automated estimates of driving times to various destinations (e.g. 10 minutes to 237, 25 minutes to 280, etc). These signs are updated dynamically, presumably to reflect current traffic conditions, and I have found them to generally be pretty accurate.
But my question is this: does anyone know how they actually work? Is there a traffic helicopter taking pictures and some human expert who then guessimates based on these pictures and updates the sign? Is it automatically counting the number of cars that pass certain checkpoints in a given time period and estimating based on that?
What is actually going on? Does anyone know for sure how these signs work?
2006-12-06
13:58:00
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4 answers
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asked by
Gordon Str
3