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Signal magnet

Magnetic field trips engine sensors at traffic lights
  [vote for,

According to California motor vehicle regulations, bicyclists have all the rights and responsibilities of drivers of motorized vehicles on public roadways from which they are not specifically prohibited. Among these rights is the right to use the left-turn lane to turn left at an intersection. The problem is that many traffic signals, including but not limited to almost all left turn signals, activate only when they detect a vehicle in a particular position on the roadway. The large circles cut into pavement at intersections are wires. When a car idles over one of these circles, the engine generates a strong magnetic field, which in turn induces an electrical current in the wire buried under the pavement below. This system works great for cars, but not for bicycles. When there are no cars handy to trip the signal, cyclists are forced to dismount and cross intersections as pedestrians, or break the law in order to continue pedaling through the intersection. In cases where a smaller street intersects a larger street with more traffic volume, the traffic light is often set such that it never stops traffic on the high-volume roadway unless the sensor detects a car in any lane on the smaller street. This again is very inconvenient, since many such intersections to not possess adequate pedestrian crosswalks. Solution: an electromagnet that stores momentum while the bicycle is either moving or braking, and generates a magnetic field discharge powerful enough to trip traffic signals. Any suggestions on feasibility, design, and implimentation?
sierkejd, Oct 28 2003


       "Any suggestions on feasibility, design, and implimentation?"
That's what you're supposed to provide.
phoenix, Oct 28 2003

       Yes I like this idea. In the UK I have a cyclist friend and some of our lights use sensors at night, and this really annoys him.   

       Why not have dynamic brakes, that trains have, so when you slow down to the red light, you end up generating lots of electicity to power an electromagnet?
Carcical, Oct 28 2003

       The loop sensors in the road don't detect engines, they detect any suitably large chunk of magnetoresponsive material, as this changes the inductive resistance of the circuit. A magnetic field will not have much effect on it. My old steel bicycle would set them off with no problems, but my new bycicle, made of aluminum, with carbon fiber wheels, fails to set them off every time.
Freefall, Oct 28 2003

       Chainmail bicycle shorts and iron Viking helmet with horns.
Laughs Last, Oct 28 2003

       Okay, how about a button, either recessed into the turn lane itself or on a pole on the divider? Make it just like crossing the street at a crosswalk.
phoenix, Oct 28 2003

       Way too low-tech. We need RFID transponders built into the bike. And flashing LEDs, lots of flashing LEDs.
krelnik, Oct 28 2003

       Video stores and credit crad holders would LOVE this.   

       I am laughing as I ride around erasing every tape and card within a 50 foot radius.
xylene, Oct 28 2003

       Where the lines for the sensor is visible, aligning the bike frame along either side should trip the sensor. If this doesn't work report the sensor as faulty to road traffic authority as they can change sensitivity.
PiledHigherandDeeper, Oct 28 2003


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