One-bit Mechanical Marble Computer


Heather, Zach and myself created a one-bit mechanical adder (with a carry function) that runs on marbles. I found the basic design online and we modified it to our purposes. Zach and Heather used cardboard, foamcore and genius to prototype the flip-flop mechanism, then mounted each on a cardboard box, adding ramps and chutes to carry the marbles through the system. The flip-flops tilt to the left to indicate zero, and to the right to indicate one. So the top indicator denotes binary 1, while the bottom indicator indicates the carry bit, or binary two. Here’s a movie that I made of the adder in action, before I decked it out in rave-wear.

The plan going forward is to implement the design in wood, with additional bits (maybe eight or 16) and a subtraction function. It would be interesting to add a crank mechanism that carried the marbles back up to the top, perhaps in a single turn. This would allow for multiplication.

3 Comments on “One-bit Mechanical Marble Computer

  1. Just fantastic!
    I had a dream about a very similar device a few short years back and have been scouring the internet for people of like-thoughts.

    I had no luck in said search…until now.
    To re witness the same basic principles I saw take effect in my dream is just…wow….

    Mechanical devices fascinate me for some odd reason; so much so that I’ve strongly considered going to school for engineering–the sole purpose being to engineer a massive mechanical computer powered by marbles and gears 🙂

    Anyway it’s just a dream for now, but thank you for helping me to relive it ^_^


  2. This is fantastic. A cool idea to make it from cardboard. And James F, I too share that dream.

  3. figured out my own design couple weeks back, it can handle numbers up to 255 and can add, subtract, multiply and divide! your desgin looks nice aswell and gave me some inspiration! good luck with future projects!