- #1
darkfall13
- 33
- 0
Hey everyone!
I recently picked up a motorcycle for class/work commutes because walking home at 11pm from the lab is not fun. But I have come across something of interest.
Some intersections keep a green light on the main street and red on cross streets until a car pulls up. Before observing that I had sat at intersections forever, finally opting to "right on red" around until I got heading in the right direction again.
So clearly something senses a vehicles presence at the intersection, I ruled out weight sensors because that seems too easy to "fool" (ie have a mob of people stand on the spot and could get the light to change maybe). So I'm going to guess something such as how metal detectors work with detecting magnetic fields, which does make sense, a car does have a lot of iron on it. But what would you think the detecting threshold of something like this be? Or in other words, if I bought a couple rare-earth magnets and put them on the bottom of the motorcycle would this create enough signal to trigger the stop lights?
I recently picked up a motorcycle for class/work commutes because walking home at 11pm from the lab is not fun. But I have come across something of interest.
Some intersections keep a green light on the main street and red on cross streets until a car pulls up. Before observing that I had sat at intersections forever, finally opting to "right on red" around until I got heading in the right direction again.
So clearly something senses a vehicles presence at the intersection, I ruled out weight sensors because that seems too easy to "fool" (ie have a mob of people stand on the spot and could get the light to change maybe). So I'm going to guess something such as how metal detectors work with detecting magnetic fields, which does make sense, a car does have a lot of iron on it. But what would you think the detecting threshold of something like this be? Or in other words, if I bought a couple rare-earth magnets and put them on the bottom of the motorcycle would this create enough signal to trigger the stop lights?