Multi Spindle Gang Router Config.

I have been mulling this around in my head for some time now. Unfortunately I don't have the programing skills to pull this off by my self.

I would like to set up a gang router with up to 6 spindles each with its own independent Z axis. Each of these Z joints will need to have their own independently adjustable offset, (to allow for setting tool depth), and I would like to have the ability to disable each individual joint as needed (might only need 1, 2, or 5 at a time). .When a joint is disabled I would like it to remain at its home position and not move until called for. I am not opposed to having all of the Z joints move to home when enabling/disabling joints.

Otherwise this is just an ordinary 3 axis machine.

My questions are does the connecting and disconnecting of joints to the Z axis, and the addition of their respective offsets need to be done in the kinematics file? How to handle homing of each of the Z joints (much simpler than a gantry setup since synchronization isn't an issue). Do some of the newer more customizable GUIs like G-screen avoid the rotary/linear axis joint assignment problems that Axis has (can joints 4, 5, and 6 be truly seen as linear)?

If the offsets and disable/enable of Z-joints would be best handled just in HAL I might be able to do it all with Gantrykins. But I am not sure if it is the best option. If it would be best to run it through the kinematics then. I am going to need help making a kins file that sets up all the necessary hal pins to do the job. I am also a bit confused about how the forward and revers kins should work. The one way seems simple enough Z=joint2+offset2, joint3+offset3... But the other way doesn't make sense to me, would I have to just use one joint as a master for feed back, but what if that joint is disabled? Plus how to handle the disabling of joints in the kins?

PS I was planning to use servos not steppers (but they might be step/dir servos)

Well that is enough thinking out loud for now.

andypugh wrote:

Todd wrote:

My questions are does the connecting and disconnecting of joints to the Z axis, and the addition of their respective offsets need to be done in the kinematics file?

I don't think so, I think you could do it in HAL.

But you might also be able to do it with gantrykins. I don't know if there is much advantage in having a joint for each spindle. (I am not sure how to set joint offsets other than by homing, but you might be able to home each spindle/joint to a toolsetter)

If I don't have a joint for each spindle, how do I home them, or jog them when they are not connected to the Z axis signal? There will be times when it will be necessary to control each of these joints individually, such as when setting tools up.

Are there documented ways of controlling a non official "joint" in Linuxcnc? Quick searches for things like controlling tool changer carrousels hasn't turned up much for me yet.

I will need to be able to adjust (fine tune) the offset of each of these. So my plan was to add a hal offset pin for each of these joints with a user gui panel to make those adjustments.