Both Dylan and I are members of The Student Space Programs Lab (SSPL). We are nearing completion of the OSIRIS-3U Cube Satellite (CubeSat) and need a better way to track our deadlines. We have used spare hardware to create a functional piece of Lab equipment which will serve to keep members mindful of our mission's timeline and otherwise interested.
What it does
Our clock goes beyond the usual timekeeping tasks, pulling data from Accuweather's API and displaying it on screen along with the current time. The design is capable of displaying daily High and Low temperatures and the forecast Precipitation for any location in the world. The display updates periodically with new information and displays an animation of an SSPL rocket dragging time along with us.
How we built it
The device you see is made entirely of spare parts. I had a Raspberry Pi lying around and the displays had been worked with before but never used for a real project. Custom hardware-level drivers were developed to display characters on the 16 segment displays. Ascii characters are used as indices in a lookup table and shifted out to the 24 16-bit shift registers on the device. We constructed a cardboard housing out of spare materials.
Challenges we ran into
First off, the wifi situation: PSU wifi is not built for these kinds of events. We wound up using a mobile tethering solution so that we could ssh into the Pi to program it. We had some trouble finding the Accuweather API keys but had no trouble integrating with their API after finding it. In the last hour our Wifi drivers have died and we're attempting a recovery. Prospects look good.
Accomplishments that we're proud of
I've never worked with a Raspberry Pi this closely before. Hardware level drivers provide a manageable challenge and are something I'm personally comfortable with. I've learned more about linux in the last 24 hours than I have in months of toying with the Pi. This also served as a great teambuilding exercise for SSPL lab members.
What we learned
Ultimately, if it ain't broke, don't fix it (with respect to the wifi drivers). Conversely, if it is broke, why not fix it? We made something unique out of junk that would otherwise be scrapped.
What's next for The World Clock and Custom Adhesives
This project will continue to live on in the SSPL lab, albeit in a more polished form. We plan to have three clock displays, one for local time, one for Japan time (we know a PhD student there), and one will serve as a mission countdown timer and eventually a mission count-up timer.