Full tutorial:

https://learn.adafruit.com/rack-and-pinion-bot/

Reciprocating Rack and Pinion

Learn how to create an automated geared mechanism with hypnotic motion. Use the Adafruit CRICKIT and Circuit Playground Express to make it dance! This is a mechanism for converting rotary motion to linear oscillating motion. The gear appears to bounce back and forth as it continuously rotates. As the wheel spins, the gear turns and oscillates between two tracks. It emits clacks and sloshes sound while in motion creating the sense of white noise. The teeth engage the lower track as it rotates. When it has travels the length of the slot, the teeth clears the end of the track and catches the teeth in the upper part of the track.

Adafruit Crickit for Circuit Playground Express

https://www.adafruit.com/product/3093

Adafruit Circuit Playground Express

https://www.adafruit.com/product/3333

TT DC Gearbox Motor

https://www.adafruit.com/product/3777

3xAA Battery holder

https://www.adafruit.com/product/3842

Visit the Adafruit shop online - http://www.adafruit.com

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