Retrofitting a Claw Crane Game for Twitch Play

You know the game: it’s a cabinet stuffed with toys that you try to fish out using a claw gripper. The claw moves around on an overhead crane gantry, and players use a joystick to control the movement. When the position is just right, a button lowers the claw and theoretically picks up the prize and drops it into a chute for retrieval.

Of course, everyone knows the toy (usually a cheap stuffed animal) is just going to slip out of the claw before it gets anywhere near the chute. Maybe it’s the seemingly easy nature of the game, or the mechanical movement, that draws us in. Whatever the case, lots of quarters have been fed into these types of machines.

Luckily for your coin purse, you can now try your luck on Twitch with Ryan Walmsley’s Pi Claw. Walmsley‏ has retrofitted an old pub-style claw game to be controlled via the Internet, and has made the fun available to everyone (at least during specified times). To give it a try, head over to https://piclaw.xyz and make a guess as to how long the claw should travel in the X and Y directions to snag a toy.

To make this work, Walmsley‏ first removed the original control electronics from his salvaged claw game. Then a Raspberry Pi 3 was added, which provides both a Python-controllable platform for Twitch as well as GPIO pins for the rest of the components. A couple motor drivers and switches later, and the hardware was ready to play! For more details, follow along on Walmsley’s blog.