A Stargate for Your Desktop
Engage those chevrons and establish a wormhole!
Stargate SG-1 is my favorite TV show, and I was in the midst of making my girlfriend watch the entire series when I saw that Instructables was having a PCB design contest. So, it was only natural that I design a desktop Stargate PCB.
Going into this project, I knew I wanted it to have a DHD you could use to engage each chevron on the Stargate, and eventually to establish the wormhole. But, PCB fabrication costs are based on the overall size of your PCBs, which meant I had to get clever about the shape and size of the PCB.
Eventually I settled on the designed you see. The main ring of the Stargate is 4 inches in diameter, and the DHD PCB fits in the center of that. Each of the outer corners around the Stargate are supports: two to keep the Stargate upright, and two to stabilize the battery holder that acts as the base of the DHD. All of the pieces are held together by thin tabs, and snap off easily.
I designed the physical shape of the PCB in Autodesk Fusion 360, and exported it as a DXF to bring into KiCAD as my Edge Cuts layer. Then, in KiCAD, I designed the schematic. An ATtiny85 provides the logic, and controls each of the eight LEDs through a 74HC595 shift register. The ATtiny85 also checks the capacitive touch pad on the DHD PCB for taps, and that touch pad required a custom footprint.
After laying out the components on the PCB, I had one major task left: adding the glyph silkscreen. That was also custom, of course, and I used GIMP and InkScape to create the images. Then, I took advantage of KiCAD’s built-in bitmap converter to bring them into the silkscreen layers.
With the PCB design done, I sent the Gerber files to Seeed Studio Fusion for fabrication. A week and a half later, I received the boards from DHL. The boards turned out perfectly, and I was very happy with the price and quality. The last step was to 3D print chevron covers and the LED diffuser for the wormhole in the center. Overall, it turned out very well, and the only complaint I have is that the blue wormhole LED is a bit too dim.