What looks to be a cross between T-Mobile’s Sidekick and a Nintendo Switch is actually an ultra-mobile portable computer (UMPC) designed around the Raspberry Pi. rahmanshaber created the open source mutantC handheld PC using a unique 3D-printed slide-out enclosure that reveals a physical keyboard housed under a display. It also has an expansion header that can be used to connect add-on boards, including Arduino shields.
“A Raspberry Pi UMPC. An open platform device to use and create. It is fully open source hardware. So you can hack it as you wish. You can make your expansion-card like GPS, radio, etc., and attach them. You can access all the ports of the pi, and the back part is attached with four screws. It can hold a 4" or 3.5" touchscreen. Also, have a physical keyboard attached via USB. It doesn't need any custom image of Raspbian. You can use vanilla Raspbian and install the LCD driver, that's it.”
The mutantC is outfitted with a custom PCB that is compatible with the Raspberry Pi Zero, Pi 2, or Pi 3, although rahmanshaber states the Pi 4 runs too hot to be utilized for his build. He also says you can use any Raspberry Pi form factor SBC, including Asus’ Tinker Board S, Pine H64 Model B, and Banana Pi as well. The keyboard portion is designed using 43 tactile switches, which are laid out in QWERTY fashion, and are driven by SparkFun’s Pro Micro.
On the display side, the mutantC with any 3.5 or 4-inch Raspberry Pi LCD screen, not anything larger or smaller will fit in the 3D-printed case. rahmanshaber has uploaded a parts list, PCB, and Gerber files, along with an extensive guide on his website for those who would like to make the mutantC UMPC.