Amy Khoshbin’s Butt-crack detector… Her blog is here…
using a Lilypad Arduino, vibrating motor, and a photoresistor (measures the amount of light in your coin slot), you will make a wearable apparatus. when the photoresistor/your coin slot is covered, the hip-pack is at rest, when it/your coin slot is exposed, this triggers the vibrating motor to start vibrating & let the user know.
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