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Traffic-Flow Algorithm Can Reduce Fuel Consumption
thecarchik writes "New projects from German automakers Audi and BMW promise to ease congestion simply by looking at traffic signals and driving style, in an effort to smooth the flow of traffic. Through a test course in Munich, vehicles were able to post phenomenal fuel efficiency gains simply by adjusting the timing of traffic lights depending on traffic volume — to whatever speed provides a so-called 'green wave' of four or more synchronized signals."
Not only is it astounding that this isn't done, it's old hat. Where I grew up, the main arteries were all set up so that if you traveled at the speed limit, you'd hit all green lights in one direction in the morning, and all green lights going the other direction in the evening. It saved gas, dramatically reduced average travel times and kept everyone going at the speed limit.
Instead, the main arteries where I live now are all set up to turn red when a car triggers a sensor on a cross street. The end result of that is that a 5 lane thoroughfare stops 15 cars every 50-100 yards because one care on a tiny side street is making a right turn onto the thoroughfare. A 2 mile drive can easily take 5-10 minutes with no traffic, just because the lights are setup so stupidly. And god help us if there's traffic (like, say on Black Friday or something like that): going half a mile to get on the freeway easily takes me 15 minutes, just because there's a light every 50 yards, they're not coordinated, and only 2-3 cars are actually able to cross the intersection at a time.
I'm always wondering if I should go to the city council meeting and ask why they're supporting terrorists with this inane system. The loss in gas mileage is atrocious, and the reason for it is just plain stupidity.
Those who can, do. Those who can't, sue.
Which inductive sensors suck hard for cyclists. I frequently go grocery shopping early in the morning or late at night when there's practically no traffic -- wanna make a left turn? Your choice: sit there for upwards of 5 minutes waiting for a cager to come trip the light (and then they have to wait for you to get through the intersection, a delay I'm sure they appreciate), or disregard the signal (yep, that's an infraction -- being on a bicycle gives me no immunity to laws, just to sensord) and turn when it's safe, without causing grief for others. I always come to a full stop, then turn left when there's no traffic, just to demonstrate a level of caution should that light be under observation, but I'd almost invariably be clear blowing straight through.
Fortunately, one light along the way has cameras, NOT to ticket unwary marks for racing a short yellow, but to control the intersection. Car pulls up? you get a green in a few seconds, just like the loop sensors. Bike pulls up? you ALSO get a green, although the same delay means it'll be green before you get there, and you get just enough time to make it through before yellow. I wish more lights were set up this way.
Besides, for the purpose of maintaining a green wave at traffic speed, I suspect cameras are the better oiption, as you can use the camera of the intersection you're controlling, whereas the induction sensors are usually too close (won't show the wave until the lead vehicles are practically stopped), and you'd need to use the sensors from the previous intersection.
U-Turns aren't legal here, but I frequently turn right, then turn around in a driveway or parking lot, and still get back to the intersection in plenty of time to beat the light change.
You have to love Australia. That particular manoeuvre is illegal there. Also illegal is exiting a roundabout from the same road you entered.
Truth is everybody in Australia is a criminal. You just have to wait until some prosecuting authority thinks it's your turn and they find the rule to nail you with.