Over at the perhof website they've written a simple yet useful tutorial on how rotary encoders work, how to read the signals coming from them and finally how to interface them with an Arduino. Rotary encoders are quite useful for user-interfaces - they're the type of knob you can turn endlessly, but still read their rotational direction and travel in either direction. Some also have a push button built in, so they can be used for numerical or menu control and selection. Or controlling Pong. However they're generally misunderstood by many beginners so this tutorial will be of great use.
If you found the project above interesting - but not sure how to start with Arduino - then the best way to learn is with our Experimenter's Kit for Arduino:
The package includes a wide variety of parts, sensors and modules including: a servo motor, lights, buttons, switches, sound, sensors, breadboard, wires and more. Furthermore a Freetronics Eleven Arduino-compatible board is included to make this an extensive hobby experimenter, inventor and starter kit. However we don't leave you alone to figure it all out, included is a great project and instruction booklet, plus access to a supporting web page and software examples. In other words - this is everything you need to get started for a fun range of electronics and Arduino related projects!
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