Thanks for all the input everyone

@bot I like the idea of using spring mounded rollers - the challenge there would be ensuring they have enough grip. It's probably worth my exploring it however because if that works, the whole motion system would be much more "out of the box".

@Danal Would love to hear more about how you've managed to offload more complex logic to other controllers. Will hit you up!

Thanks @deckingman - Agree the "belt" config would be vastly simpler (& would make a great addition to the Duet too!)

In my case however, it wouldn't work The machine I'm trying to design is a CNC machine which would be cutting beams of wood. With a router bit flying around and exerting considerable force on the beams while cutting it, we need clamps to hold it all in place in addition to controlling movement.

In the "actual" design we'd need two of the component I sketched, in front and behind the router bit, so it would be a bit more complex again.

Reading into your answer however, is the general solution to this going to be "write custom firmware"?

Hi all - I've been tinkering with the design of a new (I think) style of machine where the Y axis can be significantly larger than the "body" of the machine.

I've knocked up a video to show how the mechanisms would (conceptually) work.

https://youtu.be/D8_z1pKf81Q

I'm pretty comfortable with physically building this, but I'm not sure where to even start with the electronics side of things.

The challenge (as I see it) is in a conventional setup, you control a single motor to control the Y axis.

With my setup, you'd need to control 3 motors (2 clamps and a 1 Y axis motor), AND have some logic that "resets" the Y axis every 200mm.

Pseudocode for "reset" process would look something like this

If(Total Y Axis Movement / 200 == Whole Number) Then {

• Stop Y axis movement
• Activate grip on stationary clamp.
• Release grip on sliding clamp
• Move Y axis slider back to it's "starting" position.
• Activate grip on sliding clamp.
• Release grip on stationary clamp
  }

Can it be done? If so what would be the best way to do this? Can I keep using "conventional" G-code commands (ie G1 Y3000 F3600) to control the Y axis and configure the Duet in some way that it knows to run the "reset" script every time a 200mm breakpoint is passed? Or do the smarts for this live in raw G-code?

Thanks heaps in advance for any tips and advice