SignalGuru Helps Drivers Avoid Red Lights 436
cylonlover writes "Researchers at MIT and Princeton have now devised a system, dubbed SignalGuru (PDF), that gathers visual data from the cameras of a network of dashboard-mounted smartphones and tells drivers the optimal speed to drive at to avoid waiting at the next set of lights." In their testing, the system saved drivers about 20 percent in fuel.
You can do that right now (Score:2)
When I approach a red light, I don't continue driving and then stop, but start braking immediately and bring my speed down quickly. I then continue rolling at relatively low speed (with the shift stick in neutral, so the car doesn't brake on the engine). Often, I've still speed when the traffic light turns green. This works too if there are cars in front of you, but of course worse the longer the queue before the traffic light is, as they have to pick up speed.
I've always been waiting for the time that my T
Re:You can do that right now (Score:5, Informative)
(with the shift stick in neutral, so the car doesn't brake on the engine)
On a modern car this is bad for fuel consumption - in neutral, the engine is burning fuel to idle, but under engine-braking conditions the ECU cuts the fuel entirely. So if you used the brakes (wasting kinetic energy as heat) and then put the car in neutral to avoid slowing down further, you wasted a load of fuel. Better to just let the engine brake the whole way.
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Mod parent up - This is one of the most common misconceptions I've come across in any walk of life.
Most people really don't understand the importance and value of engine braking in general, and believe the opposite of reality, that it's bad for the car and that it uses more gas. I am so sick of tailing behind people crawling down mountain passes, breathing in 6 months driving worth of their burning brakes.
Using the engine to slow down saves gas and brake pads, and down steep hills is much safer as the c
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It's even worse if the car behind you has a different neutral speed (chance approx. 100%) and needs to either continuously brake or occasionally give some extra gas in order to not crash into you or slow down to the point where it stops too far before the traffic light.
You might save your own fuel, but you're adding cost and being a pain in the arse for everybody else.
Just drive normal; don't brake at the last moment and don't brake before you have to.
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By modern car you mean just about everything post 1990 without a distributor.
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(with the shift stick in neutral, so the car doesn't brake on the engine)
On a modern car this is bad for fuel consumption - in neutral, the engine is burning fuel to idle, but under engine-braking conditions the ECU cuts the fuel entirely. So if you used the brakes (wasting kinetic energy as heat) and then put the car in neutral to avoid slowing down further, you wasted a load of fuel. Better to just let the engine brake the whole way.
True, but missing a sense of scale. The "load of fuel" used to idle an engine (at high vacuum) during the few seconds that you could engine brake before coming to a stop is rather small compared to the "load of fuel" that would be required to bring yourself back up to speed.
If you want to be a hyper-miler, then kill the engine altogether anytime you are not using it for acceleration or cruise - I wouldn't advise this for most people, it's more important to focus on the traffic situation around you than con
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The most fuel efficient strategy is to break hard just once, as soon as possible, and then let the car roll at a speed
Did you read the parent at all?
You break gently using the engine (using zero fuel for all that time) *then* when you reach desired rolling speed you put it in neutral.
(Assuming you have a neutral...most gas guzzlers don't...)
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Aaargh, did I really type "break"? ptui.
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Why do you need to brake hard?
Hard braking is a sign of wasted energy.
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Braking in general is a sign of wasted energy. It doesn't matter how hard it is: Whatever the rate of deceleration, or the mechanism for doing so, you're just converting X units of forward momentum into Y units of heat.
But whatever. Braking early to match a light maximizes average velocity, which both gets you there faster and minimizes fuel consumption. Braking harder (ie: earlier) simply contributes to that effect.
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More like: when you slow down too much the car will stop the engine. That's usually not an exactly smooth transition. Happens when you forget to use the clutch. Remember OP was talking about manual gears.
On the other hand, this is also how you can actually start an engine, useful in cold conditions (with older cars) when the engine is still cold. When slowing down, if the engine shuts off the moment you press the clutch, release the clutch again and the engine will be forced to start. Helps preventing an e
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>>Why would you think the engine cuts fuel completely?
A friend of mine optimizes for this when he hypermiles. He has a widget hooked up to his car's computer, so he can see when it cuts off fuel to the engine (especially - under which circumstances). He's learned to trigger those circumstances on the interstate, and can usually get 60MPG out of his stock 2002 corolla without being (too) annoying to other cars on the freeway.
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That has nothing to do with engine braking, but is a cool idea. You can accelerate, say up to 90mph then coast...the NASCAR guys do that at end of races when they are trying to not run out of fuel.
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When you engine brake, you put the car in a lower gear, which increases the revs on the engine, which requires more fuel. Why would you think the engine cuts fuel completely? First, it needs fuel, even at idle. Second, it needs more fuel to produce more rpms in the lower gear.
Obviously, you don't know much about cars.
When you put the car in a lower gear, and you have forward momentum, this momentum turns the wheels, which then turns the engine. When the gas pedal is not being pressed, the ECU does not prov
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Another way you can potentially safe fuel is by turning off the engine at red lights.
http://www.slate.com/id/2192187/ [slate.com]
The technology on the Prius that this article mentions seems interesting (automatically putting the engine in a sort of standby mode where you just have to push the gas pedal to start it again)
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The technology on the Prius that this article mentions seems interesting (automatically putting the engine in a sort of standby mode where you just have to push the gas pedal to start it again)
An lot of cars in Europe already have this (normal cars with no batteries in them, not just Prius). When you're stopped with your foot on the brake the engine switches off. When you lift off the brake to go for the accelerator it starts up again.
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how does that work in a manual transmission car? no really I like the tech, but i also really like manual transmissions, so i'm wondering if i can have both.
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How do I keep the AC going when I cut the engine at red lights? It was 112 yesterday.
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Battery perhaps?
Unless you're stopping at the red light for a few hours, it shouldn't be a problem.
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No, your 1999 Civic AC unit uses a belt that is driven by the engine.
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Run it off the battery? My car (a 1999 Civic) can run the AC with the engine off...
No it can't. If you're in a US market then your Civic uses a pulley to turn the air conditioning compressor. The air blown out may stay cold for a few minutes, but after that the air will start to heat up again. I was going to go to the trouble of looking up the AC Repair manual at autozone.com, but the website runs slow thru my VM and VPN connection. Suffice it to say that my brother has a '99 Civic and I have worked on the car w/ him before.
In fact, I know someone with a 2007 Mercury Mariner Hybrid an
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This is bad for emission, however, because most engines at least till the late 90s probably till today give plenty of fuel to start the car. Also if you do a lot of stop and go you might even trigger a catalytic converter too slow to warm up code.
Try thinking positive for a change...it works wonders.
The Prius has a more powerful starter motor that was designed for more frequent use.
You mean .... cars that have this feature are designed to do it?
Wow!!! How is that possible???
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I've heard similar things suggested elsewhere, but is engine braking really avoided in the US? When I was taught here in the UK, engine braking was a primary method of braking the vehicle from any speed (you apply the brake while either remaining in the current gear or down shifting and letting each gear engage with no accelerator applied) and is used basically by everyone.
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Also here in UK, taught to take foot of gas and let the car coast as much as possible until you need to brake. This is not always possible as there are ALWAYS dickheads that have lead feet and are right up to your bumper (fender) because they want to get to that red light faster. If you can let the car coast then do so, also wastes less energy from not using the brakes until you really need to.
Of course, that kind of driving to traffic lights may be different for [electric] cars with regenerative braking.
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Most of us in the US own automatics (not me, haven't owned one in 25 years of driving), which makes engine braking hard. Although they have dual clutch multiple speed selector automatics now days, most people don't ever touch the gear selector except to go D, R or N.
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Wooo hooo, I'm in the .0001th percentile!
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the common complaint i hear is "rush hour is too much work in a manual" I've done the 45 minutes to drive 5 miles commute thing, a bit of planning goes a long way.
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Of course we can. The gearshift has lower gear positions that limit the automatic transmission to the lower gears specifically for this purpose.
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You can in every automatic I've ever driven. Are the transmissions so different in the states?
No. The drivers are so different in the states. :-/
I've driven in the US, Canada, and England.
Canadian roads are full of indecisive morons who can't figure out where they need to go, or how to get there. They also have no idea how a car works, as everything is automatic and done for them.
US roads are full of inconsiderate asshats who think everybody else on the road should get off it, so that they can change 3 lanes at once with no signal, since they're too important to have to plan ahead. They mostly ha
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I would agree 100% with your assessment, North Americans generally drive like 'soccer moms' as they call them compared to UK drivers, I noticed this while living in Canada.
Drivers in New Zealand though look like Michael Schumacher compared to both UK and US drivers, particularly in rural areas. The speed limits and speeds people drive at are faster here, but the big difference is corners - people in NZ know how to take corners at speed. I've seen refuse trucks overtaking rental cars round the outside of b
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I do this too, but it sucks when people behind you don't get it and go mad on you... And that's almost always the case.
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To what advantage ? To get a rolling start ? You push it back into gear to drive off again ? Or to block people behind you... ? Maybe you're not used driving is very dense traffic conditions.. ?
The usual action is:
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You're still saving gas. When you're sitting still you're getting 0 mpg. If everyone drove lake that you and I could save even more gas, because we wouldn't have to stop for a green light because everybody else is in such a hurry to race to the red light. People don't seem to realize that in the city, being in a hurry won't get you there any faster. The real speed limit isn't what the sign says, but what the lights are timed at.
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Working in traffic lights business, we got a problem with approach similar to yours.
A smart system will synchronize lights for optimal speed on given section of the road. If you drive 50km/h as the regulations for this location say, you will stop at most once, then get green light on all crossroads along the way. But there's this long, straight section with bright traffic lights visible from a far distance.
Nope, the problem is not assholes who speed to the next lights, then stop, then race again.
It's regula
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This may be the case where you live, but the City of Fresno, California was sued by the EPA a few years ago for artificially slowing down the speed of traffic. They timed the lights so that, if you exceeded the speed limit by more than 10 miles per hour, you could catch every light green. Otherwise, you caught every light red. They then had motorcycle officers waiting to catch you speeding.
The EPA caught wind of this and sued the city, indicating that the city was intentionally increasing smog in order t
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Oh, one more problem with your approach: Low traffic on a crossing with adaptative lights.
In case of two roads of similar level of traffic, the default program type is "AllRed". Meaning, by default if there is no traffic, all directions get red signal, so a car approaching from any direction will get green before they reach the crossing, without waiting at all.
First detectors are located 50 and more meters from the crossing, and as soon as a car is detected, the green signal sequence for that direction star
At last (Score:2)
Terrific! What would be the effects of a 20% fuel savings in town?
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Impossible because a large amount of time the speed you drive is not up to you but rather up to the queued up traffic in front of you.
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RTFA.
Honest Officer (Score:2)
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Were you running the Jesus App?
No, I was running the Your Mom App.
It won't work here (Score:4, Informative)
In the interests of efficiency, most lights here in Melbourne have been converted to a triggered system.
The idea is that the main road (determined by some guru in a government department) has right of way and light changes are triggered by cars moving over sensors at the stop lines of the red lights, in some cases (though not all) they can detect 2 cars per lane. Of course the habit of many drivers to sit back a good car length from the stop lines often means that they do not get close enough to the coils in the road to properly trigger them and as a result you get a few drivers saying"to hell with it" and running through a red light after waiting for 10 minutes. It is really funny to then see the lights change a matter of moments after, in response to the car driving over the sense coils in the road.
The result is that there is no correct speed to catch the green light because there is no direct coordination between lights.
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In Zurich, the urban planners are proud of their ability to force drivers to hit as many red lights as possible. They feel this will discourage people from driving in town, and somehow reduce pollution. Whether the net result of all those cars accelerating and braking all the time is actually better is another discussion, but if they ever thought that a system like this was becoming popular (thwarting their carefully annoying design) they would adjust somehow.
In case you are wondering, this is not my imag
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Of course the habit of many drivers to sit back a good car length from the stop lines....
Where I live, we have a different problem. It seems that many drivers don't understand what the big, thick white line at the intersection means; nor do they understand what the set of thin, spaced lines well beyond that point means. Far too many drivers here invert the meaning of those two symbols, and end up stopping just beyond the thin line closest to the intersection.
This is particularly common for drivers in the left turn lane, which is particularly problematic for drivers trying to make a right turn, and for perpendicular traffic trying to avoid clipping the moron in the left turn lane.
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It might work even so. The predictions are done in real time, using sensing data gathered by an iphone camera mounted in the car. As long as the triggering wasn't hugely irregular, the predictions would probably still be accurate enough to be useful. The paper did mention that they tried it with both fixed-timing and predictive-timing systems, and it worked equally well on both.
Roundabouts (Score:3)
The cost of the infrastructure switchover would be offset by the savings to tax payers in no time.
The government wouldn't like this because it means more money spent on infrastructure and less tax income from gasoline. In the end, less money fed to the machine.
It's good to see hackers like this out there trying to (and succeeding) in subverting the elite.
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Roundabouts are great, but when there's a lot of traffic, there actually worse than traffic lights, so they're not a panacea.
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Which is why you have dual roundabouts/traffic lights. Traffic flow light to moderate, let the roundabout self regulate. Rush Hours, you let the traffic lights direct.
Best of both worlds.
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True, but keep in mind that only works on the bigger ones.
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Um, no. I've seen those in place. Worst of both worlds. Load them up under traffic, and only one entering direction can operate at a time. (Instead of opposing directions, like in a standard traffic light.)
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That depends on a lot of factors. I'd guess that in a heavy traffic situation, a roundabout will still be better overall than traffic lights in terms of congestion. The problem is that it's much more difficult for a driver to navigate safely, given all the information that has to be processed, and in some cases, the bravery needed to use a gap in the traffic.
I used to have to drive through Aberdeen's Haudagain roundabout [wikipedia.org] on a regular basis, so I know how much of a nightmare it can be!
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Another thing to consider is that assuming people yield to traffic on the roundabout* then entrances immediately after popular exists will end up prioritised over other entrances. Depending on the importance of the various feeder roads that behaviour may or many not be desirable. With traffic lights the planners can control the priority of different entrances to try and avoid gridlock.
Also afaict if congestion backs up onto a roundabout it will completely freeze the roundabout whereas other junction types m
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The city of Gainesville, Florida, has installed a dozen or so roundabouts... drivers here have no clue what to do with them, 50% approach them according to roundabout rules, the other 50% approach them as if they are some kind of four way stop - you would think that this would improve over time, but over the last 5 years, it has not.
The installation pattern here seems to have nothing to do with improvement of traffic flow, here it seems more geared toward creating a speed reducing obstacle in an otherwise p
Re:Roundabouts (Score:5, Interesting)
They're installing 'traffic circles' in a few places in Miami now and they're making a mess of it.
A). No-one knows what todo at a roundabout. Both approaching it, and whilst on it. Whilst I've been on a roundabout, I've had people hurtling into my path. As I'm waiting for someone to pass in front of me, they stop in the middle of the roundabout and try to wave me on. (I'll let the fact that no-cars appear to have indicators in Miami go amiss...) Actually, no I won't let it go amiss, as it continues with lack of education that when there IS a roundabout, no-one ever gets the correct positioning it appears. Luckily, it's usually single lane roads, but the occasional 2 lanes feeding into it? NO-ONE gets into the correct lane for their turning (and I recall plenty of public service announcements in the UK to drill it home). So, education of what' they're trying to achieve needs to be implemented.
B) They have STOP signs AT the roundabout in many places. Apparently the city wants them, but the county has different rules, leading to Yield/Stop signs next to each other, not helping people learn what's supposed to actually happen. (Sure this part will be resolved shortly, but it's confusing everyone who's first experience of a roundabout is this).
C) Some places (key biscayne), they've filled the middle of the roundabouts with beautiful plants. That in Miami climes, grows RAPIDLY. Many roundabouts now, the vision is blocked horribly on your exit. There's going to be accidents, and it'll be totally avoidable..
D), Some states have no 'right of way' rule. Florida for example, if you're on a roundabout, you don't have right of way, no-one does. If you have an accident of someone plowing into you from the side, they may be able to fight in on court that you crossed their path. (never underestimate the power of lawyers to make a further mess of something). "He drove in front of me!" "yes, I was on the roundabout" "this court doesn't recognise a roundabout as a valid traffic item'
E) They've done a great job of building roads in the US, but without any though for the placement of a roundabout. Retro fitting them in some places is making some odd designs. (that probably just need a single stop sign, and a yield in the other direction, but no doubt funds are already appropriated)
F) And, like many other places, they put crossings RIGHT on the nearest part of the road, that with the amount of Flora previously mentioned, and the requirements to give way to pedestrians crossing, no indicators, no education on how to drive round a roundabout, means there's going to be issues.
G) odd planning. To place a roundabout at a junction, requires the 4 homes on each corner to give permission. If anyone disagrees, it won't be built (at least that's how I'm understanding it in Coral Gables). Many, not understanding what it's about, say no. The next junction, all the people may allow it. Leading to a confusing road journey filled with Stop sign, roundabout, roundabout, stop sign, roundabout, yield, roundabout with a stop sign, stop sign, roundabout. With some roads having more, some less. If you're going to do it, at least be consistent.
So, when I'm a passenger in a car and the driver encounters a roundabout and starts cursing that it's a terrible thing, and that they cause accidents, and don't improve traffic flow, I mumble under my breath "yeah, but only in America it appears..."
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D), Some states have no 'right of way' rule. Florida for example, if you're on a roundabout, you don't have right of way, no-one does.
Uh what? When you're on a roundabout, from a legal standpoint, you're going in a straight line. Someone entering the roundabout is turning. No new law is needed. Well, maybe in Florida, where the median age is approximately dead...
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You misunderstood me, I love roundabouts! Roundabouts are great, and people around here (Lisbon, Portugal) tend to use them correctly. It's just that when there's really _a lot_ of traffic, they get locked up much more easily than a junction with traffic lights, since changing lanes to get to the right one in order to turn away becomes difficult. Mix in some people trying to cut ahead, and it becomes almost completely locked up pretty fast.
as long as i can remember (Score:2)
i've always said "dont drive down this street, theres a fucking roundabout and every time you go into it, someone just about kills you. whoever the fucking idiot is who put that roundabout in obviously doesnt live on planet earth. they should have built more bicycle lanes and made it easier to walk around the city instead of this bullshit"
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I guess it depends.
I live in the Netherlands, where a lot of traffic lights have been replaced by roundabouts and it improves the flow of traffic a lot. I've rarely had dangerous situations, in fact the false sense of safety that a traffic light gives is probably more dangerous. Atleast you're paying attention when crossing a roundabout. With traffic-lights people just floor it whenever they get a green light, regardless the idiot that just crossed a red light.
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Besides saving fuel, there is a entangled issue of losing time in traffic because of slower speed (reminder: time is money).
Would I ever see the study in my lifetime that links those two issues?
Why not abolish traffic lights? (Score:2)
Couldn't the same processing power and communication be used to avoid the need for traffic lights completely?
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Yes it could ... if drivers scrupulously respected the indications of the magic box on the dashboard.
We can do even better and smarter (Score:4, Insightful)
Instead pf reverse engineering the traffic lights timing, the responsible offices could simply document them, also on road signals.
All the stuff needed to reverse engineer the timings will produce more CO2 than simply say them.
Nonetheless, that idea is really smart.
The human drivers era is ending (Score:5, Interesting)
If you look at all the available safety systems coming in the next generation of cars:
- automatic braking
- infrared night vision
- reverse backup sensors
- adaptive cruise control
- lane departure warning systems
- traction control systems
- electronic stability control
- emergency brake assist
- cornering brake control
- precrash system
- automated parking
It is just a couple of steps away from turning you into a mere supervisor of your car's automatic driving.
If you add fuel efficiency to the safety concerns, it will add a new set or constraints that will give automatic driving an advantage over human driving.
those things have been coming for 30 years (Score:2)
you can find advertisements from the 1980s about radar systems warning people about stuff behind them.
in reality, the cheap models of cars will not have any of that stuff, in order to keep the price low.
that is almost a necessity in this new age, where the distribution of wealth has become so uneven, where you have 9% unemployment measurements (and much higher in reality) , tens of millions of people on food stamps (a historical high), where minimum wage is not enough to live on, let alone buy a car, and mo
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Right up to the point where they're required by law to have them, like seat belts, air bags and antilock braking systems (required in the EU and will likely be required here in a few years).
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They had stripe following demo vehicles in the 1950s. Look far enough into the future, and the "cheapest" cars will be the ones that drive themselves - drivers will pay a premium for manual control. Actually, I think right now we are all paying the premium for manual control, already the "system" (counting roads, signals, vehicles, garages, etc.) would be cheaper overall if every vehicle were automatically driven. Today's tech can handle 100% automated vehicle traffic, what it can't handle is mixing auto
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Great. That will bring to the road even more idiots slowing me down when I am just five minutes after traffic hours trying to make it to the meeting I am overslept.
How about going draconian on would be drivers in traffic schools, drive tests and written tests? How about devising a system PREVENTING bad drivers to EVER step on the road?
How about acknowledging that there are far more people who will never be able to drive adequately that we know?
How about stopping yapping about how driving is not right, but a
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Wonder how the class divide and inability to buy a new car will affect that vision.
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The biggest problem I see for an auto-drive system in normal driving (accident handling has it's own set of problems) is going from the combination of a rough map, a rough position indication (according to wikipedia ordinary GPS currently has an accuracy of arround 20m) and visual clues to successful junction navigation (particually at junctions with lots of exits packed close together).
Maybe i'm a pessimist but this isn't a problem I see being solved without adding infrastructure on the ground to provide a
Its been tried (Score:4, Interesting)
tells drivers the optimal speed to drive at to avoid waiting at the next set of lights."
The problem is that the speed to travel at to not stop at the next set of lights could be 12 km/h or 1.5 times the speed limit. It is hardly ever a speed you are actually going to travel at. We had a system in Melbourne which did this. They had to change it to not display a speed above the speed limit and then the displays showed stupidly low speeds.
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So you can drive very slowly to the next light and not wait or you can drive there quickly and then wait. Either way your average speed is going to suck.
If that is happening on the main road through an area then someone really needs to fix the timing of the lights so cars on the main road can proceed along it at a reasonable speed without having to stop (granted this can become difficult in areas where there is no one "main road")
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Say the speed limit is 60km/h and to get a green at the next intersection you have to travel at either 61 km/h or 12 km/h. Few car drivers will choose the lower of those two values.
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In that case I'd say the problem lies with the timing of the traffic lights themselves. The village where my parents live had a "green wave" for the main road well over 30 years ago already. At the beginning of the village they just put a sign "green wave at 50 km/h" (which is the speed limit), and the traffic lights were timed in such a manner that you would only have to wait for the first light (or, if lucky, not at all). After that continue at 50 km/h and a minute or two later you've passed half a dozen
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Melbourne obviously had their traffic lights timed in a manner that only with extremely high or low speeds you could catch the next green. Instead of timing them to match traffic moving at normal speeds.
The road system is a grid and the system attempts to link the signals in all four directions. But outside the "green wave" there will be at least two solutions for getting the next green. One will be above the limit and the other will be very low.
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While we don't have such a system in my city (London, Canada), if you do 10km/h over the speed limit, you hit many more green lights. I think they're encouraging speeding to make more money off fines.
Beaten by Cheezburger network... (Score:2)
http://cars.failblog.org/2011/08/26/funny-car-photos-smartphones-can-make-you-more-fuel-efficient-gas-science-percent-cooler/#comments [failblog.org]
Its a sad day for /.
Great for speed demons (Score:3)
Don't forget: when you're perfectly synchronized with the traffic lights at 30 mph, you are also at 60 and 120 :)
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when you're perfectly synchronized with the traffic lights at 30 mph, you are also at 60 and 120 :)
Not really, but I do know for a fact (having learned while working in the FDOT district 6 planning office, and personally experienced first hand many times) that the lights on US1 in South Dade county (Miami) are synchronized well above the speed limit in the direction of rush hour traffic flow. Speed limit is mostly 45, but if you can manage to keep moving at an average speed of 55-60 (sometimes 65), you can get green lights all the way from Homestead into Downtown. Having lived there for nearly 20 years
Better Idea (Score:2)
Instead of saving 20% in fuel, why don't we rip up most unnecessary lighted intersections and replace them with roundabouts. The initial cost would be high, but the fuel savings for ALL cars will recover that cost in a few weeks.
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Well they could always skip the roundabouts, and instead properly time the lights to speed. I mean in my home town the lights are set so poorly that it takes longer to drive from one end to the other on a busy friday, than it does to drive 35km on the highway. I'm almost sure it's deliberate, either that or it's incompetence from city engineering.
No, if you are doing it during traffic hours. (Score:5, Insightful)
Roads are not for "saving" on fuel or brakes. Roads are for getting from A to B.
You selfish "saving" on fuel leads to you occupying extra road time-space. You are basically hogging it, take it from other drivers, which leads to heavier traffic, in fact, very often it will lead to creation of extra traffic jams.
Instead of that technology, they should invent technology that will get medieval on the asses of those local government official who intentionally program traffic light system to slow drivers.
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Insightful my fat arse.
Aggressive drivers who try to get from A to B as fast as possible cause traffic jams. Drivers who flow with the traffic don't. That technology is made explicitely for a smooth traffic flow.
Re:No, if you are doing it during traffic hours. (Score:5, Insightful)
What really ensures smooth traffic flow is for everyone to be traveling at about the same speed, with no idiots getting right on someone's butt then hitting the brakes. When they do that, it sets up a standing wave where everyone behind the idiot has to slow down.
I try to do my part by acting as a low-pass filter: when I see people up ahead of me slowing down, I let off the accelerator and slow down gently so that nobody behind me who's paying the least bit of attention has to hit their brakes, thus removing the standing wave.
Obviously this can't help when you've got at-grade crossings when people will stop to wait for traffic so they can turn left, but it's a good general rule.
Re: (Score:3, Informative)
The only reason for "aggressive" driving during traffic hours are idiots who DO NOT "flow with the traffic". Because of them now the traffic (which you call "aggressive") flows around them causing extra speeding diff between lanes, extra lane changes.
As for speed. The higher the speed, the better the smooth traffic flow fixes the problem of jams, because of the extra space that the car takes from the road. At the same 3 sec interval you will take more time-space on the road at lower speed, because larger pa
But ... (Score:2)
You don't really have that much leeway in how fast you drive. Sure 5 above or below the speed limit is fine, but anything more and you will be pulled over at some point.
Wont work around here... (Score:2)
IT seems the idiots here think drag-racing from light to light make it faster. it turned green! FLOOR IT!
Until they either increase the requirements to have a drivers license this green light trickery will be ineffective as all the nimrods will bunch up in front of you causing traffic delays and negating getting a green light. It's why I stopped all hypermiling tricks in town, all the other drivers drive like idiots.
Ignoring the REAL use case... (Score:2)
OK, now can they combine the data with the data from Trapster so you can know when it's worthwhile to EXCEED the speed limit in order to break out of a holding pattern where you're driving against the timing-optimized direction of traffic and would otherwise end up hitting every single red light? When I drive to work in the morning, about 3 miles of my trip goes against the direction FDOT optimized the timing. If I follow the speed limit, I'll hit every light, every inch of the way, every time, guaranteed.
Not so simple... (Score:2)
Around here the only way you're going to be able to avoid red lights is by speeding excessively; it's like traffic lights have been set up to penalize anyone driving at or near the speed limit. It seems like American traffic engineers solve every problem by adding more traffic lights, stop signs and slowing drivers every chance they get.
Roundabouts are great, but they're far from being a panacea and Americans are going to have to change their driving habits too. Americans are too self-righteous and too comf
Wrong way around (Score:4)
Put more sensors and "intelligence" in the traffic lights and let people drive around as normal.
Traffic light systems are really stupid, last night I was driving home at 2am and came to some traffic lights, they changed to red and there was no other cars around.
Arse about (Score:3)
Put more sensors and "intelligence" in the traffic lights and let people drive around as normal.
You've got that completely arse about.
Put more intelligence into the drivers so they stop doing stupid things. People thinking that doing 80 (Kph) in a 60 zone is normal are the problem, not traffic lights. In the vast majority of cities traffic lights and speed limits are designed to work together to ensure traffic flows correctly, when Dingbat McHoon drives at 90 in a 60 zone he is the problem, not the traffic lights.
Driving is somewhere where the Dunning-Kruger effect is very obvious.
Re: (Score:2)
The application tells you how fast to go if you want to catch every green light. It is not there to tell you that one is coming up.
But that level of understanding would require at least reading the summary.
Re:Stay in Gear and look ahead (Score:4)
No.... When your engine breaks, you use no fuel. It's pretty obvious, really.
Re: (Score:2)
It would certainly be more efficient, but would take a lot of costly infrastructure to implement. What's worse, there is unlikely to be the political will to achieve this - public transport is perceived as a form of socialism in the USA.
This, on the other hand, can be done in software, using pre-existing infrastructure - many people have a smartphone. If the 20% fuel saving is consistent, many people could pay for their phone AND their network bills out of the savings they make in fuel. It's probably even w
Re: (Score:3)
Socialism keeps getting redefined. Yours is not the original definition.