I’ve been on a course on high speed reading for the past three days so I’m just getting back to the Little Dipper project.

Stepper Motors

These motors are out of junk scanners. I was a little concerned they’d be slow but they’re not too bad when using acceleration (rather than running them at a fix speed and starting and stopping them abruptly).

You can see in the video below it behaves quite nicely with smooth stepper control. I’ve been jogging it for a few hours like this and everything is staying cool.

System Architechture

I’m looking at the system architecture now. I think it makes sense to limit the Arduino to just managing X-Motor, Y-Motor and brush servo.

If it’s tethered to a computer and the computer just sends commands to the Arduino microcontroller by serial/usb, then we can have a lot more processing power and a nice interface.

It seems logical to use processing.org to process the images, create tool paths for the brush and manage queuing of the commands going to the machine. Perhaps I can have a job queue.

I will have a look at all prior art before I make any final decisions on the architecture and software.