Filament Roller IR Sensor Version 2

A Kickstarter campaign for this product is live:
https://www.kickstarter.com/projects/522476987/filament-roller
Make a donation and receive a finished Filament Roller. Thanks for your support~

This is a prototype IR sensor and alarm which detects the direction and speed of your filament spool. This sensor will sound an alarm when your spool stops due to filament-jamming, nozzle-clogging, extruder-grinding, motor-stalling, or out-of-filament.

This second version is a stronger and easier-t