What 3946 did was use an Arduino and two XBees to make a remote control T-shirt launcher.
All the code for the Arduino (and I believe the Firmware for the XBees) is avalible on our github:
https://github.com/frc3946/MobileAirCannon
What we did was have the XBee standalone in the controller, using its dedicated IO lines as inputs. Then we had the XBee on the Arduino sending that data from the Controller to the Arduino via Serial. Then I made some breakout boards for PWM (S + -) and Relay (A B -) ports.
Here is the hardware we used:
Arduino Leonardo (an Uno or Mega would work just as well):
https://www.sparkfun.com/products/11286
2x XBee Pro S1
https://www.sparkfun.com/products/8742
Arduino XBee Shield:
https://www.sparkfun.com/products/12847
XBee Explorer USB (For Programming XBees):
https://www.sparkfun.com/products/11812
XBee Explorer Regulated (For use in Controller up to 12volts):
https://www.sparkfun.com/products/11373
The rest are just buttons, joysticks, battery holders, and switches to make the controller, and some perfboard and headers for the additional breakout headers.
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Programmer - A creature known for converting Caffeine into Code.
Studying Computer Science @ Louisiana Tech University
Associate Consultant @ Fenway Group
2012-13: 3946 - Head of Programming, Electrical and Web
2014 - 3468 - Programming Mentor
2015 - Present - Lurker