Introduction: Traffic Light Trigger for Your Bike
Not feeling ferrrous enough to trip the induction loops that trigger green lights? No problem - just epoxy a rare earth magnet to your shoe! Inspired by a product marketed to motorcyclists, which is basically a big neodymium magnet to stick under your ride. I thought it might be better to get a slightly smaller magnet closer to the road.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.
Step 1: Dremel As Needed Between the Lugs of One Heel
I always put my right foot down, so I ground out a little extra space on my right heel. Luckily, my Sidis have tall, widely-spaced lugs, so I didn't have to remove much material.
Step 2: Epoxy the Magnet, Backed With a Washer, to the Shoe
I used PC-7 heavy-duty epoxy paste and coated the entire magnet, both to protect it and to stick it firmly to the heel. Backing the magnet with a washer helps to focus the magnet field, aiming it down (and not up into your heel, not that it should do anything to you anyhow).
Step 3: Using the Magnet to Trigger Lights
Look for the round or diamond-shaped cuts in the asphalt that show where induction loops are buried at intersections, and set your heel down near the tar lines. Here in Portland, some lights helpfully have a small bike between two hashmarks which you're supposed to line your wheels up with, which is a the perfect spot (and more sensitive, too).