Above, a lovely photo by drew & mithi in the process of making a 3d printer. The precise motor control is aided by an opto quadrature encoder disc. Looks like they used the analog inputs to watch for interrupts and wrote some PID controller code. Hopefully they’ll post it up too!
oh hey, you’re right! i did see it, but i didn’t recognize it as the same people
Actually they are not the same people…
abigmagnet.blogspot.com is my blog and the folks who took this picture were the ones working on a 3d printer (nice idea that).
I had been experimenting with PID control to reuse printer motors and the optical quad encoders they often have for position control.