When you create logic circuits using ICs or FPGAs, you can’t easily visualize their operation without special tools. But if you’ve ever seen a mechanical computer (like the Computer History Museum’s Babbage engine) operate, you know you don’t have that problem. Just like it is fascinating to watch a 3D printer or CNC machine, watching mechanical logic gates work can be addictive.
[Anthony] wanted to build some mechanical logic gates and set out designing them using Inkscape. Unlike some common mechanical gate schemes, [Anthony’s] gates use gears to implement the logic operations. He sent the designs off to a laser cutter service and got back parts cut from 3mm acrylic.
A little adjustment and a lot of hot glue resulted in working gates (see video below). [Anthony’s] site has some good animations showing the operation of each gate type. You can also find downloads of the SVG files for all the components.