Hacker News Reader

Cams with the shaped required to draw the digit for each digit arm. You can see there's a rod with various cams on for each digit, four of them in total. I imagine there's some sort of slider to engage a cam for the "current digit" so when the redraw triggers the selected cam is the one used for the motion.

Many automata use a similar design to to achieve preprogrammed movements, like writing, drawing or playing an instrument.

It doesn't look like a Fourier series. It couldn't do sharp angles if it was (like for the 5 or 7).

Looking at the pictures, it looks like a two axis parallel robot where the arms are controlled by a cams with complex shapes. The cams can be seen in picture 11/16.

I see what you mean, I think you must be right

I recall a young man building a portion of the 'Game Of Thrones' theme video. Think watching a real-life mechanical, clockwork Winterfell or Kings Landing twisting and rising all out of pop-up flatwood in your spare bedroom.

I've tried a quick search on Youtube for the video but couldn't easily find it.

The kid's friend joked about how soon HBO would hit him up on copyright.