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Check Traffic Congestion Online
braddk writes "Looks like traffic helicopters will slowly become unnecessary in Denver, as an ongoing construction project implements online traffic data. The traffic is monitored via "vehicle counters" placed at the onramps and in between interchanges. Although only a 10 mile section is currently monitored, plans are to add more sensors as they complete sections of the larger project. They also have a lighter version for mobile phone users.
Click here to see the Flash version
and to check out the current traffic in Denver. Now I can check whether I really want to head to work in the morning." Kinda like that project in Finland.
Atlanta's traffic Sure it is not in pretty flash, but is is much more extensive.
The reporters can sit in their studios and follow the congestions real-time and will report it with regular intervals on the news. Works fine.
Aren't similar systems in use in lotsof other places?
I'm in a Unix state of mind.
We've had this in the UK for a decade. It's called traffic master. Speed senors are mounted on freeway bridges all around the country and provide constsnt traffic flow information, which can be relayed to a map display on the dash.
Speed sensors give rather better information for this purpose than car-counters. See http://www.trafficmaster.co.uk/
This sounds like the Coordinated Highways Action Response Team. It has an interactive map with colored arrows indicating the speed of traffic on both sides of the highway for a variety of roads in the DC/Baltimore area.
(But please don't Slashdot it, or I won't know if it's safe to leave for work!)
A simple car count will yield garbage data because it is the speed of the cars that passes a given point that really matters.
If 10 cars pass a certain point in 5 minutes, that EITHER means that the traffic is fine and smooth, OR slow as hell.
But if one could get the average speed of the cars passing the point, on the other hand...
Check that: :-)
http://www.transport.ntua.gr/map/
It works for years now, and is very accurate
you can find it here
The Atlanta area has had something similar for awhile. It's pretty handy if you want to check traffic on your way home.
Plus, you can modify the map to display the locations of traffic cameras around the area. When you click a camera, it shows you the current view from that camera.
It's a pretty nifty system.
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We've had this in Chicago for some time, and it works quite well.
http://www.ai.eecs.uic.edu/GCM/chicagoland.html
It's a good place to do a quick check before you head out, just to be sure. However, once you're already in your car, I still think nothing beats the radio stations' traffic people telling you how it is.
http://www.dot.state.mn.us/tmc/trafficinfo/map/ref reshmap.html
Though it seems that only central Minneapolis/St. Paul is working right now.. could it be the mounds of snow?
The modern radar systems that are used to count the traffic are capable of resolving and tracking down to individual vehicles in very dense traffic flows.
These things (based on military targetting radar) probably work out cheaper than fitting gps and associated hardware to every single vehicle.
Such things have existed for years in the US.
Here's Houston: http://traffic.tamu.edu/incmap/
Here's Dallas: http://dfwtraffic.dot.state.tx.us/dfwweb/
These don't use 'car counters' (sounds expensive), they simply use the RFID tags that the tollway system uses to automatically charge you when you cruise through at 70 mph. They just set the sensors up on the side of the road (cheap), and send the info in. That's why they can afford to have coverage over the entire city, not just downtown like that slow Denver map.
What would be great is a standardized system to push these maps to LCD screens in your car.
Nothing new in France either.
Roads have had sensors for at least a decade.
Used for different purposes
- traffic monitoring (accidents, etc.)
- driver information by huge screens on the road, telling how long to this and this direction ; and I find it really nerve calming to know how long it will take and be able to organize (once it only said how long - in distance - the congestion is, which I don't care about)
- website for 4 years.
Here we have two type of sensors
- simple loops, which only give information about the "coverage rate" (that is, proportion of time there is a vehicle on the loop. Funnily, this figure is heavily correlated with the state of traffic and the speed of the vehicles. 0.1 is heavy traffic and 0.2 is congestion. I do not recall exacly the figures but you get the highest throughput for a magic "coverage rate" which corresponds to around 57 kmph (~37 mph).
- double loops are simple loops 1 meter away ; correlating data from the two gives you the time decay between them and so the speed of vehicles, in a more reliable fashion than just simple loops ; in particular with these you can ajust the nominal traffic model with observed speeds so your model integrates real road conditions (snow, rain, saturday night...) and single loops can then give you very accurate information.
On heavily trafficked roads (eg Boulevard Peripherique in Paris) you have a single loop every 400m and a double every 2km AFAIR.
The Dutch government plans to introduce something like this, mainly for road pricing ("kilometerheffing")(make the use of congested roads more expensive to fight that congestion).
there is no doubt that if drivers know they will get caught the roads would be a safer place
No, there would be less speeding. But there are loads of other ways to endanger fellow road users, and these other traffic offences can't be monitored automatically.
Fully automated speed traps don't lead to better road behavior, they just lead to annoyance at the government for placing a lot of emphasis on only one factor in traffic accidents.
We've seen this in the Netherlands, where about 90% of traffic tickets are now automatically generated by speed traps. These speed traps have triggered a tenfold increase in the number of traffic tickets over the past 10 years, to the point where on average every Dutch car driver will get one ticket a year. Are our roads safer now? Hardly. The number of road fatalities has dropped a bit, but there are so many factors contributing to that (safer cars and roads, more congestion leading to a lower average speed, etc.), that the increase in speeding tickets can't have helped much.
Meanwhile, respect for the law has plummeted, and road rage increased, due to speed traps and speed limits that are perceived as pointless.
Never posted so excuse any faux pas.
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I've been watching the Toronto Highway system for a few years now. I'm not sure when they went live but the Ontario Governments Ministry of Trabsportation has made their cameras accessible to the public when I head they revamped their web site. (http://www.mto.gov.on.ca/english/traveller/compa
Even the Weather Network here in Canada has a feed you can access. (http://www.theweathernetwork.com/camera/toronto/
It is very precise, as not only are the microwave oscillators very stable, and the speed of light itself is very constant.
If you find yourself near a microwave doppler supermarket-type door opener that has the mixer-out indicator visible, you can see the indicator dim and brighten as you cross wavefronts in the microwave beam, meaning the phase of the waves reflected from you arrive back in time to either aid or oppose the oscillator transmitting the microwave energy.
There is a lot of cool stuff you can do with microwaves. They are really bouncy things.. they bounce off of darned near anything conductive.. and deriving the doppler is as simple as using a plain junction diode which is exposed to both the transmit and receive side of the microwave beam.. the multiplication of "local oscillator" and "RF" occurs at the diode itself and the resulting "IF" will be in the low audio region ( for human velocities anyway ) and quite easily processed by simple amplifiers.
"Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]
...and the data is available from many sites.
You assume the sensor is "dead," but these traffic management systems set ramp meters based on conditions further down the road. Traffic may be rushing towards a stop. Minneapolis-St. Paul has had these sensors and ramp meters for years now. One of State Senators got a bug up his backside about them and forced MnDOT to do a "study" (well, it was a real study) that involved shutting down all the ramp meters for weeks. The results? A disaster. Congestion increased severly on most roads. Most trips *increased* in drive time (yes, even when you include time spent being an "asshat" at a ramp meter).
The interesting thing was that this was not 100% true. Some routes got better. And drive times improved over the course of the study, although they didn't come back to anywhere near as good (on average) as they were before metering. In other words, people found alternate routes.
One outcome of this was the appearence of lighted arrow signs along side streets of the most congested highways that come on to point motorists on to alternate routes when congestion is severe. Unlike the ramp meters, these are mere suggestions. But it seems to have improved things.
Transit is a huge political issue here. The Republicans took over Minnesota government last election largely by promising massive road building instead of public transit. That's pretty remarkable for MN which has long been considered a Democratic stronghold. People get "het up" about traffic.
Traffic metering WORKS. Sure, you get annoyed waiting on the ramps, but they really do improve travel time.
Oh yeah, the study did improve their meter rates. They were able to speed some meters up and slow some others down and *improve* travel times over the pre-study metering system. It didn't stop me cursing that senator every time I commuted during the study! BTW, in 2001, when the study was done, there were 233 metered ramps in the metro area during the morning rush, and 283 metered ramps in the afternoon rush. I don't really know how many meters exist now, although MnDOT's web site could probably tell you. They have data on the study and its aftermath on their web site.
Houston's real time traffic map
Houston Transtar does traffic monitoring, as well. They use the signals from EZTags (you know, those things you stick on your window that automatically pay a toll for you on toll roads) to measure aggregate traffic speed, and then display it all on a nifty, color-coded map. Accidents get notated with little "!" marks and you can see information on lane closures. They also have histograms available, so you can see what the average speed at any given time of day is supposed to be, and live views from the traffic-monitoring cameras all over the city. Check it out.