Vehicle: Car: Communication
Traffic light g-spot locator   (+3)  [vote for, against]
Don’t wait for the timer…

I looked and couldn't find this one being done yet......

When you’re the first person at a light your car is detected by the traffic controller system. This is done with sensors in the ground that detect a large metal object above itself. The sensor is actually a weak radio transmitter and receiver (think handheld RadioShack metal detector) If you don’t land exactly right on the sensor it is possible you car not be detected. You then wait for the timer to let you go forth. My idea is to install traffic light sensor sensor’s into cars to let them know if they are on the sensor or; if they need to move a smidge to the right. A few LEDs in the dash to notify the driver of the presence of the radio emission and the general direction it was coming from. So you could find the sensor if you weren’t on it correctly. Get on the it, let the traffic light brains know your there, and be on your way fastar.
-- evilpenguin, Aug 09 2007

Or just put magnets on the bottom of your car http://www.instruct...EL8EH6RZ1REP286X29/
[discontinuuity, Aug 10 2007]

Alternatively, send out an RF beam 300 yards ahead and 10 yards wide upon the press of a button, to have the lights starting their timer before you even get there...
-- vincevincevince, Aug 09 2007

Oh, that kind of g-spot. So not something to help you on first dates then.
-- marklar, Aug 09 2007

Around here, the sensor coils are usually fairly easy to see, as they have been cut into the pavement and filled in with tar. And they are usually in the area that you should be stopping in, so there's little need to find them.

The only times I've seen a car not over the coils is when a driver pulls 'way too far forward through impatience.

The only times I've needed to worry about just where on the coil I was located was when I was triggering the sensor using my bicycle frame or a toolbox. The sweet spots are in the corners, supposedly. You can step out of the pedals, lay your bike mostly down, and trigger the coil. You can also get out the entrance of a gated lot by putting your toolbox over the entrance coil.

After all that: Just how is a "traffic light sensor sensor" made?
-- baconbrain, Aug 09 2007

vince^3, I like your idea better!

And I know of few sensors on lights around my house that are picky when it comes to dection of cars. The one at the end of my street is horrible. My street (sidestreet) intersects with a bust street, and the timers for automatic greens for my street take 2 minutes. If you hit the sensor right, about 20 senconds. I know from expirence where to drive to hit it, but its infurating driving behind an someone who doesn't know where to go.

This idea could also be used to detect speed sensors on the highways, and speed cameras in some area's.

//After all that: Just how is a "traffic light sensor sensor" made?// Radio emmission dection (radio frequency scanner, with specific frequency squelsh settings)
-- evilpenguin, Aug 09 2007

I'm not sure what they use where you live, [EP], but around here they just use an induction coil, which can only broadly be considered a radio transmitter/receiver. The basic idea is still good though.
-- 5th Earth, Aug 10 2007

//So not something to help you on first dates then.//

Not that kind of red light, [marklar]; also, not that kind of first date either! Plus, er, reversing it would be kind of awkward too you know.

//Traffic light g-spot locator//

Of course you'd always get that red light runner who chooses to speed up and beat the sensor warning light on the dashboard.
-- quantum_flux, Aug 10 2007

A device that helps you find your passenger's g-spot in the time it takes for the light to turn green? Sounds like WIBNI to me, how's it work?
-- globaltourniquet, Aug 10 2007

Please explain why that is not a radio transmission at all. Induction is magnetic only? Or electro-magnetical only? Seeing as how I don't understand, please exlain further than blanketing with 'wrong'.....
-- evilpenguin, Aug 10 2007

Ooh, a girl's private parts that glow red when you're away the right area, yellow when your finger is nearing the right area, and green when you're right on it.
-- phundug, Aug 10 2007

<shakes head and rolls eyes>
-- k_sra, Aug 10 2007

Warning, science ahead.

The principle of the induction coil is pretty simple. You take a coil of wire, and run AC through it. Because it's a coil, there is a slight resistance to the AC current (look up inductance). It also generates a fluctuating magnetic field (this could, very broadly speaking, be considered a sort of radio signal of absurdly low frequency). This magnetic field will create a sympathetic current in anything conductive next to it, like a car. This induced current will then generate it's own magnetic field, in opposed polarity to the original field. This secondary field increases the resistance of the induction coil, which is detected, and trips the traffic lights.

In basic terms, if you run AC through a coil of wire, the resistance of the wire increases when you put metal things next to it.

Now, will an electrical engineer please tell me how I got this wrong, because I'm pretty sure I did.
-- 5th Earth, Aug 10 2007

//or; if they need to move a smidge to the right//

How would you move to the right once you've stopped? Or is this something that would give you indication as you were approaching the stop, so you could adjust before stopping?
-- awesomest, Aug 10 2007

Earth and beaton, science is Appreciated... thanks

Okay, so its a 60hz alternating current electro-magnet that is subject to variable resistence, dectected by the controller circuitry(?)

Wow, I really thought it was more complicated.

And danieol, reverse and get on the sensor, assuming there is nobody behind you.
-- evilpenguin, Aug 11 2007

[Beep] There are actually systems in place that do just that. They work on radio identifiers on the emerigency vehecial that communicate with traffic lights to go force greens. There were a few test markets where the system was tested.

(sorry for the sp errors, its late)
-- evilpenguin521, Aug 12 2007

[5th Earth] //(this could, very broadly speaking, be considered a sort of radio signal of absurdly low frequency)//

In principal, induction coils can use higher frequency AC current, and avoid being effective radio transmitters by being too small. They could, broadly speaking, be considered absurdly weak or short range radio transmitters.

The road ones may use roughly 60Hz current (do they?), but the handheld metal detector circuit I've looked at works at a much higher frequency
-- caspian, Aug 12 2007

OKay, so the real question, to complete my idea, is it possible to dectect the feild it creates, wether it be radio or electro-magnetic?
-- evilpenguin, Aug 13 2007

I should think so. A 60Hz alternating magnetic field is a fairly distinct thing. Get an antenna tuned to 60Hz (or reasonable harmonic of it) and it'll generate a current anytime it's near one of the sensors.
-- 5th Earth, Aug 13 2007

random, halfbakery