Finally! A fool-proof, incredibly solid, incredibly easy, non-finicky encoder system!
The Dagu encoder system is specifically for the Little Black Duck motors, but will work with just about anything that spins. The kit consists of (2) 8-segment magnetic discs, self-adhesive mounting stickies, and really nice hall-effect sensors. The sensors have already been soldered to servo-style 3-pin connectors, no soldering required.
The concept is quite simple, as the discs spin and each magnetic "segment" of the disc passes the sensor, the sensor clicks low. The sensor itself can vary greatly in distance from the disc with no loss in performance. Put simply, stick the disc to something, get the sensor kinda close and boom, you are counting revolutions. No more adjusting IR stuff, no more painting white and black stripes on stuff. These sensors are as straight-forward and solid as they get.
Included in the kit: