Turn red lights to green?

[EagleKeeper]

Originally posted by: kherman
This is cool and everything, but won;t this just turn all the lights red atthe intersection?

The Opticom system triggers an override in the Traffic Signal control box. The box then will activate the light green in the direction that the strobe detects. After a preset time, the signal will revert back to its normal Red/Green/Yellow programmed cycle.

 

[Electric Amish]

I've never seen an emergency vehicle change a light color here in Utah.

amish

 

[Kevin]

Originally posted by: Electric Amish

Originally posted by: kevin000
I always thought they should put sensors into traffic signals. That way when there's a major road an intersection of a main road that no one uses, the light stays green until a car is waiting to pass. Its so practical and would alleviate most traffic problems and congestion that it would NEVER happen...

They already do that for many intersections. They use pressure lines buried in the asphalt.

amish

I don't think New York does that. I know they have them on Bridge Tolls.

I went through a Teller/EzPass Toll and it wouldn't work. So I asked the attendant and she goes "Its broken" and I go "Sucks for You" and proceeded to go. Then in her ghetto-Brooklyn voice she yells "You best be paying the $6." So I proceed to back up to pay her and she starts yelling "SIR, DO NOT BACK UP" so I stopped and backed up again. Boy was she pissed that I backed up twice. I couldn't understand why I was in the wrong if THEIR system was broken. They should have disabled the light that said "Cash/EzPass" but she chose not to. I don't mind paying but she could have been a little smarter and nicer. She got what she deserved.

 

[dakata24]

Originally posted by: bmacd
i don't think you guys understand how they work. They are more commonly sold in Australia, where it works with their traffic light system. If ambulances needed them here, why would they bother turning on their lights and siren to blow through a light?

-=bmacd=-

to get traffic to slow and move over to the right so the ambulance can cruise by?

 

[Evadman]

Originally posted by: KthxBye
Ok, I'm here to explain it all. EMS, firefighters, and police can change stoplights through a technology called Opticom that was developed by 3M. Basicly, the car has a strobe on it that emits light in one of two frequencies. 10Hz for low priority, and 14Hz for high. Traffic lights (most of them anyways) have sensors which pick up the light and change accordingly. Here is a site of some guy who tried make one (most of this info comes from him), and HERE is a site that sells them. (but only to government agencies)

HAHA! I live about 30 minutes from that Guy! ( or from the intersections he has listed anyway ) Small world.

 

[NogginBoink]

Originally posted by: ffmcobalt

Originally posted by: Cyberian

Originally posted by: madthumbs
The sensors buried detect metal, a bicycle can trip it.

Some probably do, but some work on weight of the vehicle.

Most work on weight, not sensing metal.

nik

Huh?

Why would you bury a mechanical device that coud fail, when an metal detector (a capacitor or wire loop) would have no moving parts, could probably be repaved over, etc.

I have no idea what "most" work on, but any engineer worth his salt would go for the no moving parts answer.

A bike magazine had an article a few years ago instructing bikers to lay their bike as horizontal as possible at a stoplight to get the metal detector to sense the bike.


And that's a TOTALLY DIFFERENT issue from devices that can be added to stoplights to "see" an oncoming emergency vehicle and change the light green before the vehicle gets there. Many of these work by detecting the strobe lights, although recently Dallas investigated the use of an infrared device for the inner city "express" buses. (I have no idea if it was adopted.)