Say hello to HANS

hans_frontI wanted some new desk art for my office, and this is the result. It’s a digital orrery that simulates our inner solar system with unnecessarily high precision on a hilariously underpowered microcontroller.

Testing my newest contraption…

digital difference engine


A long time ago (after I built my FIBIAC), my friends at Makerbot used their botfarm to make a boatload of 3-digit counters for me. I hadn’t really decided what to do with them at the time, but I thought it would be fun to see how far I could push the delightfully-inefficient instruction-set architecture I had come up with. After languishing for 2 years or so, I finally decided to do something with them. The punch-card chain of the FIBIAC has been replaced by a somewhat more robust stepper-driven instruction drum, and there are now 8 (!) 3-digit counters. Here is a short test video of it running a 4-instruction ‘Difference Engine Emulator’, and computing a table of x^2 (1, 4, 9, 16, 25 …). The final result shows up on the 4th counter from the left (the white one) after every iteration. Enjoy =)

The Pocket Gutenberg

I think I started this project around 2 years ago, but got bogged down in trying design my own printable, movable-type font (it turns out font design is a whole crazy world I want nothing to do with). I recently discovered the “Write” library for openscad (along with Makerbot’s cool ‘customizer’ tool for thingiverse). The result is a neato, pocket-friendly printing press. Customize a plate of type, print it out with a 3D-printer, and then 2D-print until your heart’s content. You can finally make the tiny zine you’ve always wanted to!

Cray-zy progress! We have a booting system!

I had gotten bogged down with the data recovery effort from my COS disk pack in the last year (and my day job building slightly more modern supercomputers got a bit busier), but an awesome programmer named Andras has picked up the torch and carried it ridiculously far!

He not only re-wrote all of my disk recovery software to overcome most of the disk corruption, he also reverse engineered the file system and wrote a simulator for an entire data center’s worth of equipment (4 CPU Cray X-MP, with 4 IO Processors, a peripheral expander, printer, wyse 50 terminals, a farm of disk drives and a real-time clock module that apparently uses the AT command set), and actually got the OS to boot! His write-up about his work is pretty awesome:, including code for his simulator.

If anyone has any software for a Cray-1 or Cray X-MP, now is the time to speak up! We’ve got a working system that can run it! Now, to just find the time to get my FPGA version up to speed so I can run this!

A 3D-printable, mechanical stepper

My efforts have slowly been converging on a workable design for a 3D-printable, all-mechanical computer (with an emphasis on the word *slowly*). Inspired by this recent post I saw floating around the ‘net, I thought I would post my most recent attempt at building a fully-mechanical stepping mechanism (to replace the stepper motors used in my FIBIAC project). Eventually I will get around to integrating this with my electromechanical counter so that I have a fully mechanical counting mechanism.

And video!



I’ve been reading an awesome textbook on power-loom engineering, and it’s inspired me to try to build my own all-mechanical, jacquard-style punch card reader. I have a small 3-bit version more-or-less working, and up on thingiverse in case anyone wants to build their own. I doubt it will ever happen, but it would be cool to build a super-simplified all-mechanical computer that actually used punch cards. Maybe I could call it “Plan 2.8” instead? Anyway, eat your heart out steampunk fans!

To the sea!

A project that’s been on my ‘to-do’ list for years now is some kind of autonomous, robotic boat platform. Although I have dreams of crossing the atlantic someday, for now my sights are set on something more local. To that end, I’ve started construction on a small nautical rover. I unfortunately don’t actually know much about boats or robotics in general, and my primary tools are the laser cutter at NYCResistor and my trusty Thing-o-matic 3D printer, so my boat is kind of funny looking. Some preliminary tests have been promising so far though!

The 3D-printed propellers work much better than I expected!