Kelly, also known as "Kellbot," designed a custom controller for the cult hit Katamari Damacy. The game involves rolling your Katamari — a big, sticky ball — over everything from gum wrappers to cows, people and skyscrapers to turn into stars and planets depending on its size. The game's simple control scheme, which only requires you to use the two analog sticks on the Playstation controller, translates nicely to her giant trackball.
It uses an optical mouse to track the ball. I gathered up some cheap PS2 controllers, ripped out the potentiometers on the analog sticks, and replaced it with a digital potentiometer and an arduino. The arduino takes signals from two PS/2 mice (one for each analog stick) and adjusts the potentiometer accordingly. It's the first circuit I've ever designed, so obviously it has a lot of room for improvement.She describes it all in a video after the jump in case you want to make your own. Game companies have tried capitalizing on special controllers for video games to make them more immersive, though they never seem as awesome as the DIY projects such as Kellbot's, not to mention the crazy homemade creations people come up with. Click Continue to see that video.