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Light Traffic

senseable.mit.edu

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Re: Light Traffic

#81

Post by tqkxzugoaupvwqr »

chrisper wrote: post #70
rcarmo wrote: post #14

There's been a marked tendency to replace intersections with roundabouts and shared spaces ( https://en.wikipedia.org/wiki/Shared_space ) in many places, including the outskirts of Lisbon (as well as a few legendary mazes in Britain). There was even a BBC report on the latter (which I can't find right now, as usual, only a follow-up: http://www.bbc.com/news/uk-33303031 ). Drawing a (admittedly inaccurate) parallel wi…

I don't think roundabouts would work in the Bay area because it requires that people know how to use turn signals.

So the solution is a full switch to autonomous vehicles and a ban of all manually driven vehicles?

People will learn to use turn signals quickly if they are fined.

Re: Light Traffic

#82

Post by icebraining »

IshKebab wrote: post #49
sharpercoder wrote: post #39

Earlier quoted context omitted.

On roads where you can drive 30+MPH (50 KMPH+), I would suggest removing any possiblity for pedestrians to cross. Either make the road 20MPH (30KMPH) max where all space is shared with pedestrians, bicycles and cars - or make much better, safer & faster 50KMPH+ roads.

Is this satire? How do you walk anywhere otherwise?

Make the whole city 20mph max? Fine by me :)

Re: Light Traffic

#83

Post by closeparen »

mgbmtl wrote: post #37

I feel like so many similar proposals tend to ignore how saturated our roads are, how expensive the road infrastructure maintenance is, and how fast people expect to drive (because of long commutes from endless suburbs). We need to find innovative ways to implement forms of collective transportation (rail or what not) in already dense areas. Rail/subways have already proven how effective they are. Autonomous vehicles…

Unsustainable compared to what? New York is clearly demonstrating that it’s incapable of sustaining a subway, and it has just about the best conditions possible for such a project. You think a place that can’t even manage roads can swing a subway?

Is it sustainable to all move closer together? Not if the residents of existing cities have anything to say about how those cities are governed. They don’t want the extra population.

Re: Light Traffic

#84

Post by chrisper »

tqkxzugoaupvwqr wrote: post #81
chrisper wrote: post #70

Earlier quoted context omitted.

I don't think roundabouts would work in the Bay area because it requires that people know how to use turn signals.

So the solution is a full switch to autonomous vehicles and a ban of all manually driven vehicles? People will learn to use turn signals quickly if they are fined.

I think for now increasing the requirements to get a driver's license Should help.

Works well in Europe. Though I can understand why this wouldn't work in the US.

Re: Light Traffic

#85

Post by jakecopp »

jakobegger wrote: post #69
jakecopp wrote: post #64

Earlier quoted context omitted.

Even OpenCV running on a Raspberry Pi can pick out cars in a moving image - a bad offline solution (with a sensible fallback) would be better than a timer. On a large remote setup I think you are right though.

OpenCV on a Raspberry does not sound like something that is reliable and easy to deploy. It‘s a long way to go from something that you hack together in the living room to something you can deploy on hundreds of traffic lights, that works in every weather, that can easily be configured for different use cases, and that can be serviced by the technicians.

You are right. I'm trying to say I think the problem is development bound and not insurmountable (secure, reliable, good fallback to timer) rather than "moving, storing, and processing data" bound as per the parent comment.

Re: Light Traffic

#86

Post by jakecopp »

jakobegger wrote: post #65
jakecopp wrote: post #57

Earlier quoted context omitted.

What I don't understand is why every traffic light doesn't have cameras and some image recognition/machine learning (whether local or remote) to improve the timing - it would be such a cheap and easy fix compared to putting a sensor in each car.

Lots of traffic lights in my area already have sensors (induction loops to detect waiting cars or approaching bicycles, IR motion detectors to detect pedestrians). In some cases this is really useful (eg. a traffic light for a bike path does not need to switch very often in winter, so it only switches when a bike approaches) I think that the problem is that often there is too much traffic from all directions and even…

I believe the induction loops only sense if the first car is present. This is helpful, but can't detect the number of cars which I think is the next most important metric.

Re: Light Traffic

#88

Post by jakecopp »

rcarmo wrote: post #14

There's been a marked tendency to replace intersections with roundabouts and shared spaces ( https://en.wikipedia.org/wiki/Shared_space ) in many places, including the outskirts of Lisbon (as well as a few legendary mazes in Britain). There was even a BBC report on the latter (which I can't find right now, as usual, only a follow-up: http://www.bbc.com/news/uk-33303031 ). Drawing a (admittedly inaccurate) parallel wi…

I grew up in Canberra, known as the roundabout capital of Australia [1] as well as being the actual capital of Australia. It has a population of ~350,000, 406 roundabouts and 276 traffic lights.

In my experience they keep traffic moving really well, as long as the traffic load into each entrance is roughly equal - otherwise it's hard to enter the roundabout from a lesser used entrance.

They take up more space than traffic lights in most situations, however Canberra is a planned suburbia so that wasn't an issue there.

[1]: http://www.abc.net.au/news/specials/curious-canberra/2016-12...

Re: Light Traffic

#89

Post by niftich »

jakecopp wrote: post #57
maxander wrote: post #41

So a system that requires all vehicles on the road to have flawless sensor and communications systems can achieve some improvement over current-day technology (from the paper, approximately a "doubling of capacity" for intersections with this implemented.) This is a profoundly uninteresting result, given the current-day technology in question is "a dozen lights attached to a timer." Add devices that are several order…

What I don't understand is why every traffic light doesn't have cameras and some image recognition/machine learning (whether local or remote) to improve the timing - it would be such a cheap and easy fix compared to putting a sensor in each car.

As others are indicating, this is tech exists, and in some places it's widely deployed, where in some others it's nowhere to be found. I've seen them in several US cities and suburbs, in many states, usually along major arterials and covering the busiest intersections.

Missouri Department of Transportation's St Louis District has one of the best FAQs [1] on this tech that shows how these cameras work: exactly as you'd suspect from some OpenCV proof-of-concept.

The cameras are a more robust replacement of the in-pavement induction loops, which are much more widely deployed, but give you a subset of the information at a higher cost.

[1] http://www.modot.org/stlouis/links/signalcameras.htm

Re: Light Traffic

#90

Post by niftich »

jakecopp wrote: post #86
jakobegger wrote: post #65

Earlier quoted context omitted.

Lots of traffic lights in my area already have sensors (induction loops to detect waiting cars or approaching bicycles, IR motion detectors to detect pedestrians). In some cases this is really useful (eg. a traffic light for a bike path does not need to switch very often in winter, so it only switches when a bike approaches) I think that the problem is that often there is too much traffic from all directions and even…

I believe the induction loops only sense if the first car is present. This is helpful, but can't detect the number of cars which I think is the next most important metric.

There's also an amusing "failure mode" of induction loops: impatient people pulling up further into an intersection -- for example, aiming for an opportunistic left turn -- and they move off of the loop. The lights cycle; the left turn green arrow which would give them an exclusive phase never materializes.
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