The device uses a stretch sensor as the bow string with a row of LEDs to indicate how far back the arrow is pulled. A built-in accelerometer senses the orientation of the bow and simulates gravity for an accurate curve of the arrow’s trajectory. This is fed into an ATmega1284P.
The bow also incorporates a game that keeps track of the score on a monitor. Push a button on the monitor, and the game is reset. Push another button on the bow itself, and the game starts. The player is given three shots, and the accuracy of each shot is indicated on a target displayed on the screen, then the point value is tallied up at the end. The design is simple, intuitive, and looks like loads of fun. Check out their site for extensive documentation.
[via Hacked Gadgets]