Sensor Triggers Red Light When Speeding

Be interesting to see how it works.

average of 55 in 35 mile zone makes me want more information.

How much latitude do they give. If they're too restrictive a lot of drivers will be ticked off and could result in rash of rear enders. Time will tell.

Maybe a follow up is needed in 6 months on this.

Sounds like a very self-serving approach.

They can then automatically send a camera violation ticket without even having to have police on site. It raises the ways in which revenue for the local jurisdictions can be enhanced.

Skeptical in Maryland.
Fred

They might be using radar and no cameras.

Interesting, but how will it affect everyone else on the road/intersection at the time?

Only the Pennsylvania State Police can use RADAR in Pennsylvania, this road is a city patrolled road.

From the article linked in the first post:

"On Kelly Drive, three sensors spaced six feet apart have been embedded in each lane heading north and south near Fountain Green Drive, Montanez said.

Each sensor detects when a vehicle passes over and its speed, Montanez said. An average is determined from the three sensors to make the reading more accurate."

The road in question is a fairly winding road along the Schuylkill River, it's 4 lanes, two in each direction, and in spots pretty narrow. At least once a month you hear about a bad accident on that road, most of the time speed related.

Here's a couple of videos of a ride on Kelly drive (I don't know any of the people in these videos)

http://www.youtube.com/watch?v=eF_mF9Sy8Kc

http://www.youtube.com/watch?v=9CCH9Dx8l6s

About two years ago, the local bean counters must have had some spare money in the budget and they placed a similar device on a road here near me on Long Island. This light's sole purpose is to stop drivers going over 30 MPH on a small two lane road. The side street where the light is placed contains about 4 homes on it, so the side traffic is minimal at most. Not sure how they detect the speed, but if you approach it at any speed above 30 MPH (the local limit), the light will turn red before you get there. If you slow down to 30 MPH before reaching the light, it stays green. Each direction is independent of the other. There is no camera or fines or any such things here, it's just a speed deterrent.

Thanks for that explanation camerabob.
This really does sound like a reasonable deterrent rather than a speed trap.

Fred

It's a case of the needs (and wants) of the many being affected by the few. While the average speed was quoted as being 54.8 MPH (that's 88 Kph) it also means many were going even faster than 55. If the sensors and they are probably hockey puck sized devices in the pavement measure the speed at greater than the 35 MPH speed limit the signal change will affect all drivers, including those not speeding. What we don't know from the story is will the light trigger because a single vehicle is going over the limit or will it take several. Until we know more about how the signal and sensors are integrated, we can only guess and assume.

Based on this quote from the linked story, "If a vehicle passes the sensor going above the speed limit, the light at Fountain Green turns red" I'd say the light triggers for the first car it detects speeding.

I first heard about this on a local radio station, the guy reporting the story said the three sensors in each direction and traffic signal are tied together by wifi.

But again, it's a guess. We don't know how the sensors are integrated with the controller. While it may be that it takes only a single vehicle, it could also be dependent on the speed where going above a certain threshold a single vehicle will trigger the light or it could be an average of several vehicles traveling at a some speed above the limit. I would hold out it is a combination in that a single car doing say 15 MPH over the limit would trigger it but it would take 3 or 4 going say 10 MPH over the speed limit to trigger the change.

dohdohdohdohdoh

no money in for the crooked politicians and their lackeys

I suppose at some point, we'll get to where they can back down an offending speeder's throttle, much like our existing traction control systems do now. All they need to do is to be able to trigger that existing system remotely from a roadside sensor to make that happen.

Actually, it might not be a really bad thing if it could be triggered from a police car when warranted. Something like that would reduce those dangerous high-speed chases we see sometimes. But it wouldn't be long before it got abused and out of control, I'm sure.

After reading the news article and thinking about the situation one could increase speed every 5mph from 30 to find out at what point the system trips to red.

Once one found out what the red light tripping speed was then one could see if the red light would trip on if they were straddling between lanes, instead of driving within the lane.

The above also brings up a interesting question. I wonder if it also works with motor scooters and cycles... especially if THEY were to straddle lanes?

Now that I think about it... I also question if the time it takes to trip the red light is in direct relationship to the vehicle speed, or if the tripping time is a constant no matter what the speed is?

All of these questions unanswered via the incomplete news article.

Nuvi1300WTGPS

We already have these! It doesn't trigger a green light, per se, but what it does is if someone is approaching the intersection, it holds the green (or alternately holds the cross traffic at red) until the vehicle clears the intersection. Our town was looking at getting something like this but it was cost prohibitive. One of the State Routes in my area though has it and it has made my driving through that area that much easier. Until drivers understand how it works, there is a lot of wasted time where everything is held red, but the trick is to not panic when you see it go yellow because it sees you and will hold the yellow for you so you don't have to slam on your brakes. I do wish it had a white strobe or something like the preemption systems do for emergency vehicles so you have some assurance that it's working.

And on that state route, the loop detectors are set far back enough that when you approach the state route on a cross street late at night it will trigger the state route to immediately go yellow (and hold if necessary for any traffic that might need to clear) and then go green on the cross street in advance of your arrival at the intersection so you can go through.

For an overview of the technology see: http://safety.fhwa.dot.gov/intersection/resources/techsum/fh...

For a specific model, which is the system I am most familiar with, see: http://www.wavetronix.com/en/products/smartsensor/advance/sa...

A lot of the "smart" lights in our area were doing this many years ago, the idea has been around for awhile and is a good one. Unfortunately, this safety-enhancing behavior seems to have largely been thrown out the window in favor of shortened yellow-light times to increase revenue collection. Hopefully we'll see this making a comeback but I'm not holding my breath until the economy improves, reducing the number of municipalities desperate for revenue.

Also, if these turn red on speeding lights get too annoying, one could always jam the WiFi as they approach the device. How far the sensors are from the control box would determine how easy it would be to jam.

- Phil

I am unaware of any city other than Oakland (see http://www.poi-factory.com/node/39440) that has shortened yellow lights for revenue enhancement. You make it seem that this is more widespread than Oakland. If you have any support that other municipalities have done this, would you please give us more details.

Ok, I hereby, herewith and heretofore modify my comment as follows:

Unfortunately, this safety-enhancing behavior (of lengthening yellow light times in order to allow a car to safely pass through the intersection), seems to have largely been thrown out the window in order to increase revenue collection.

That said, you make it seem as if no other municipality other than Oakland could possibly have done this. If you can prove that this has never happened in another municipality, please provide any relevant details supporting that claim.

Thanks for the modification.

I can not "prove" that no city other than Oakland has ever reduced yellow timings to enhance revenue.

However, for three years now, I have been questioning every member who has made the claim that there have been municipalities that have "shortened" yellow times and asked for links to some source. Lots of members (in addition to the ones I questioned) have claimed that there were cities that had done this, but in each case, the true facts were that these cited cities had an intersection (may have been as many as 3) where the yellow cycle was not at the timing it should have been given the approach speed (and other factors). When the short yellow was disputed by a citizen, the timing was determined to be wrong and was corrected - most often with refunds to those caught by the improper timing. These situations were in the early and mid 2000s. The Oakland instance was in 2013.

In Florida, there was the situation where the Florida DOT shortened yellow timings (and as far as is known not below the minimum guidelines) and the municipalities did not know. My understanding is that Florida may take the step of lengthening yellow timings based on ITE recommendations that yellow lights be longer than otherwise would be calculated whenever there is heavy truck traffic or a large number of elderly drivers. I do not think this has yet happened. I hope that it will.

Opponents of Automated Traffic Enforcement love to misrepresent "short" as "shortened" and those who do not investigate links to see if they agree with the purported "facts" are eager to repeat such misrepresentations.

Since the health of our democracy depends on an informed citizenry, I try to raise questions when I find that the facts - as best they can be determined - have been misrepresented to further someone's agenda.

I took a drive on Kelly Drive today. The following video is on the east bound side. About the 1:31 mark I pass the sign, a few seconds later I go over the sensors at 40 mph. I see a car coming up pretty fast behind me and as he passes about where the sensors are the light turns to red. I thought the white car would have triggered it but he got hung up behind the RV before the sensors. (be sure to change the player setting to high def otherwise it's pretty blurry)

http://www.youtube.com/watch?v=R86YMeaZPjY

This is west bound, if you pause the video around the 2:10 mark you can see the sensor spots.

http://www.youtube.com/watch?v=Q__dSQKq8-k

Here's a few stills I lifted from my dash cam videos. The red circles show the area the sensors are embedded into the road.

http://tinyurl.com/m2hzh2m

http://tinyurl.com/kd4v7oy

http://tinyurl.com/lr77wlh

Here's a couple close ups I took with my phones camera.

http://tinyurl.com/lr77wlh

http://tinyurl.com/mvw2y57

There are three sensors pretty much in the center of each lane. Not sure how they work of course, do they each pick up in a 360 degree pattern or does it work like a big rectangle box.

Are there any signs alerting drivers where these things are installed? If not, it's mostly just wasting a lot of fuel as many drivers will likely never figure out what's happening.

EDIT: I guess I should have actually checked out the link first... duh. I retract the question.

It's an interesting strategy though, just annoy the speeders until they slow down.

Hopefully, the good folks here who generate the POI files will either add these to the speed camera database or make another file for them as they become more prevalent. That will help to save fuel and reduce emissions.

Of course if signs are posted everywhere they're doing this, I guess it's a moot point.

@JGermann: no problem, point taken.

- Phil

These are not speed cameras, in fact there are no fines or tickets involved. This is something called "Traffic Calming" First place I saw traffic calming was in New Castle County Delaware, they took a perfectly nice road and put all kinds of obstacles in the way so you had to slow down to avoid hitting them. I'll take the red light triggers over the kind of solution to speeding I saw in Delaware.

Here's one from I used to travel through in Delaware, they put all these brick islands in the road:

http://www.deldot.gov/information/projects/outstanding_proje...

Here's a few examples: (these are not from Delaware, just images on the net)

http://www.internetigloo.com/wildwood/images/funky%20roundab...

http://www.wsdot.wa.gov/NR/rdonlyres/30F86B52-9BB9-4FAB-AF9B...

http://upload.wikimedia.org/wikipedia/commons/9/96/Barrmill_...

wonder how it handles emergency vehicles??

It'll be just like any other light that's red when an emergency vehicle approaches, they'll slow down check the intersection and proceed through the light.

I didn't notice any yet but they could put those emergency responder light trippers (see below) on the pole, but I can't recall ever seeing those in use within the city limits.

http://upload.wikimedia.org/wikipedia/commons/7/73/Millersvi...

http://www.tcmfd.com/stuff/opticom.html
.

Here in Chicago speeding doesn't trigger a red light, it triggers a ticket that comes in the mail A guy at work got one and told me he was going to watch his speed carefully from now on.

Police, Ambulances, Taxis and Buses in some cities in New Zealand have a remote control to change the lights to green; I would be surprised if the USA and other countries do not have the same or similar remote control.

The two links in my last post show what we use in Pennsylvania and some surrounding states, but I have not seen their use in the City of Philadelphia, PA, where this thread is about.

In Spokane WA, emergency vehicles have a strobe light that activates a sensor in the traffic signal that gives them a green light. It only works when the emergency lights are displayed.
I have never observed those devices in any other state.
Edit: See soberbykers link.

Those strobe traffic lights are in wide use across the US. The receiver is a small cylinder mounted on the cross bars holding the lights. You will probably only see them in urban areas.They've been around for 10 years or so.

Go back two of my posts and the links I included show one and and explain how they work.

I live in suburban Philadelphia and there is pretty wide spread use of them, the city itself doesn't though.

Perhaps they should also outfit steering wheels to shock speeders?

Interesting idea....

I would like to see that in practice. Some cities have synced lights for an average speed if you go down the street. Though there are others which are completely HORRIBLE, no syncing at all!

The system in my neck of the woods is Opticom. BTW, the system records the date/time and vehicle identity that tripped it.