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Old 08-11-2006, 12:48 PM   #51
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Default Re: Traffic lights! ARG

Yes. It's called a car, but we prefer smaller two-wheeled transportation.
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Old 08-12-2006, 04:18 AM   #52
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Default Re: Traffic Lights! Ugh!

i suggest putting your kickstand down on the sensor.

always works for me.
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Old 08-14-2006, 07:51 AM   #53
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Default Re: Traffic Lights! Ugh!

Read http://www.msgroup.org/TIP148.html

I ride a Sportster. I find that simply putting the center of the engine over the embedded wire and waiting causes the light to change. There are surely quite a few places where this will not work. When I find 'em I take a different route the next time through.

These sensors are antenna and are part of a Whetstone bridge. Many just are not tuned well. What do you expect for government work?
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Old 08-14-2006, 10:15 AM   #54
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Default Re: Traffic Lights! Ugh!

You're thinking of a "Wheatstone Bridge", which is a part of a strain-gauge or Load Cell for weighing items. While I've heard of some highway depts using these, they're pretty-much obsolete in light of the developments with cameras and inductance loops (which are nearly obsolete themselves - as cameras and the microprocessors & software that control and interpret the camera signal get better and cheaper all the time).

The Inductance loop is merely a giant metal-detector, imbedded into the pavement (typically known as the six or eight-sided elongated "boxes" you see cut into intersections). There is a transmitting and a receiving loop, usually laid side-by-side, but occasionally they will overlap one-another, or be positioned one-in-front of another. It varies by each mfgr and situation.

How a these work is, an oscillating current is passed through the Tx loop at a high frequency - typically greater than 25k hz - and picked up by the Rx loop, where the signal is then processed, analyzed, and compared to the "outgoing" signal.

Anything that passes between the two loops interferes with the signal, including cars, trucks, pavement, people, etc. - so this is all filtered-out so the detector "looks" for a particular type and "size" of interference - like your average compact car - and anything "bigger" than that is automatically "assumed" to be what the detector is "looking" for (cars and trucks).

So, our new light is in, the Traffic Engineer (and I use this term *loosely*) is busy watching waveforms as various cars come through the newly-controlled intersection. He (or she!) is busy fine-tuning the timing, occasionally checking the O-scope as a Geo Metro or a Dodge Neon comes to a stop at the cross-street. Our Engineer has the gain and filtering set *just* a bit higher than the triggering mass of the smallest vehicle he sees come through the intersection, and is satisfied with a Job Well Done(TM).

But alas! No motorcycles come through the intersection on this balmy December day in beautiful Downtown Detroit, and our Intrepid Engineer is oblivious to the teeny-tiny signal that a small mass of aluminium, plastic, and titanium that your average sportbike generates. In fact, it's low enough that even most Harleys (which contain less ferrous metal than they used to, but still a significant amount compared to your typical import bike) won't generate a large-enough interference signal to "trip the trigger". Especially at 1:00am, with almost no traffic coming from the sidestreets.

It's NOT that the detector DOESN'T "see" the bike - it's that the trigger-level is set too high for the light to change state. So you're stuck, unless you can "fool" the light into thinking you're a larger interference than you really are.

As others have pointed out, one way is to put your kickstand down on top of one of the loops - get the interference "closer" to the loop, it makes it "bigger". Magnetic fields CAN affect it, but this is less-reliable than the sellers of the "Green Light Magnets" would have you believe. Being in motion also increases the interference between the loops, but re-paving without adjusting the gain and filtering *decreases* sensitivity.

The only "Sure-Fire" way to get a nonresponsive light to work, is to complain to the DOT in charge of it. That is, if you can get them to DO anything about it - otherwise, deal with it as best one can.

Now that you (and by "you", I'm referring to the "general you") know how the induction loops work, you can maybe deal with them a bit more effectively.

Ride Safe.

Parfois, on fait pas semblant
Sometimes, it's not pretend
Oderint Dum Metuant
Let them hate so long as they fear
политики предпочитают безоружных крестьян
Politicians Prefer Unarmed Peasants
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Old 08-14-2006, 01:17 PM   #55
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Default Re: Traffic Lights! Ugh!

Cheapest Route: reach back and put that centerstand down, or put her in neutral and put the kickstand down.

Cheap Route: Magnets taped/ attached to bottom the bike. DO NOT waste your money on 'kits' to do this, its just too easy to do it yourself.

All else fails run it and if the cop is hidding and catches you explan the situation. Washington has a two light cycle and legal run rule, check your local rules.
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