It seems that every day a manufacturer comes out with a new tablet computer. Thinner, lighter, faster, but it seems that they all look about the same and accomplish roughly the same things. When I set out to build my Raspberry Pi tablet I wanted something different. I wanted an all-in-one system that was usable, portable, and Linux based. Additionally, it had to look good. Since I wanted to use it on flights the device couldn’t freak out the TSA or the old lady sitting next to me.
Early in 2013 I started accumulating parts. The Raspberry Pi runs off of 5V so I knew it could be powered from a cell phone charger. Most touchscreens I could find were 12V though, making the electrical work more complex. After a bit of searching I finally found what I was looking for: a touchscreen monitor with a 5V HDMI to LVDS converter from a site called Chalk-Elec.com. I plugged the screen in as soon as I received it and to my delight it worked perfectly with the Pi, even the capacitive touchscreen. Now I knew my dream of a Raspberry Pi tablet was possible.
According to Parkinson’s Law, “Work expands so as to fill the time available for its completion.” Thus was the case for my Pi tablet. Two weeks before Maker Faire Bay Area I was helping a guy in the Shed Tech Support queue that needed some help with his Maker Faire project. Helping him got my creative juices flowing and I decided I wanted a Maker Faire project too. Crazy – right? I had all the parts and now I had an ambitious deadline that couldn’t allow for expansion. Fortunately I had started some preliminary design work so I *kind of* knew what I was going for. I happened to have access to a CNC machine, some 1/2″ Baltic birch plywood, and a relatively large sheet of scrap carbon fiber laying around to form the basis of the frame.
(Full parts listing and design files can be found here.)
After several 4am nights I completed the Raspberry Pi tablet (aka, PiPad) the day before my flight. The build wasn’t without its issues (I had to remove one USB port and the Ethernet jack due to clearance problems.), but everything worked and I was happy with the results. But what about the TSA?
This image was taken while on my flight to San Francisco. It didn’t raise an eyebrow going through security. On the plane though, a flight attendant kept walking by looking closely at the home-built gadget I had on my lap. At one point I could feel her looking over my shoulder and was sure she was going to say something. She nudged me (I thought it was over at this point.) and said, “I love that movie – you’re coming up to the best part!” It turns out that she’d been catching glimpses of “Talladega Nights” that I had playing using RaspBMC. I’ve taken the PiPad on most flights since and no one has said a word.
I’d e-mailed Raspberry Pi Foundation founder Eben Upton a few times for work, but didn’t have the chance to meet him at Maker Faire Bay Area. I finally managed to catch up with him at Maker Faire New York though. Eben is probably the most humble, down to earth person I’ve ever met. I really can’t say enough about him. After a long chat I showed him the PiPad. He gave it several compliments and after a few minutes of playing with it, he graciously signed the back at my request. His signature looks amazing on the carbon fiber!
Overall I’m very happy with my Raspberry Pi tablet. It does what I want it to do and has been a great way to demonstrate the capabilities of the Raspberry Pi at Maker Faires. (Perhaps you noticed it?) The 10,000mAh battery provides a usable six hours of run-time and the device gets constant compliments from makers. (Including Bunnie Huang!) I do wish I would have used a battery that provides power while plugged in. Other changes I’d make would be mostly software related. It’s difficult to double-click on icons reliably and the N-Trig touch driver isn’t supported by RaspBMC, (but can be compiled into the kernel if I could ever get it figured out). I’ve also considered adding a camera and an IR sensor… maybe if I build another one.