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Oh whichever is easiest for you, I don't have a parting slide and C axis at this moment is all I'm trying to do. I'm immensely grateful anyway

You can try these examples that I have working with some of those ETHERCAT servos

OK. I'm having a really hard time understanding the code base. The files don't seem to have any comments explaining what they actually do, what leads to them, or where they lead to.

If the cubic.c is only for non-trivial kinematics, how does the interpolation work for normal cartesian machines?

I was assuming that every servo period it pulls a target position and velocity from the trajectory planner creating 1ms stair steps of constant velocity, but I really can't tell.

Good to hear that you managed to get your toolchanger working.
I would hope that the PID settings can be constant. I did think that the error term can be scaled.
We know the state of the backgear and the output (spindle encoder). With the analog output, we can have at least a good estimate of the motor RPM. So back-calculating the ratio of the variator should be possible, at least to a degree.

If we scale the error term with the overall transmission ratio and tune the PID at that state, it should give reasonably good behavior over the whole range, wouldn’t it? I am not sure of this. Doing this would give a wonky error at startup (estimating the variator would take a few rotations, I think), but it should be fine before the spindle is fully started up, I think.

But I may have an error in my thinking. Control theory is not my strong suit.

Might be worth asking in the Remora thread.

I am working on a similar solution, but want to do it as a comp, since I got my comp for the turret working this weekend.

Gear ratio can be inferred from spindle speed / commanded voltage, corrected to frequency, corrected to RPM. (You are a step ahead of me there, with your vfd frequency out put).

I expect we will need a constantly changing set of PID settings, as the inertia varies over the entire speed range.

I always wondered whether the back gear can change gear with the spindle running, but it would be pretty pointless, given the huge 6.5:1 spindle speed change, so I will only trigger it stationary.
Cheers,
Mark


 

And you see the pin iocontrol.0.emc-enable-in toggling high?

Maybe something odd with the amp-fault pin for the W-axis?
joint.N.amp-fault-in

Yeah, I would also happily sacrifice full screen for M1.

There have been recent updates to the driver. Which LinuxCNC version are you using?

@Andypugh

If you want me to subsidize the shipping cost as a contribution to the project, just let me know.  Once you get an address to @jschulze and a shipping cost is determined, I can paypal either you or @jschulze directly.

 

If you have the index connected to the 7I96S index input, then a standard
pncconf or MesaCT created hal file will have the correct connections.

jetbadger wrote:

From what I gather, logic.s0free should be an AND device, so with personality=0x105? Maybe there are other essential things there? I assume SPIN0-xx  signals are distributed in another file?

 

Yes, logic.s0free is 0x105

There are probably other essential ingredients missing from that hal file.  Best bet is for me to post my whole config...  You've got two options:

• I can give you a slightly out-of-date version right this second.  It has all the spindle/c-axis stuff in it, OR
• Wait until tonight and I'll give you the latest version
  • Includes a switchkins component for my separate parting slide, plus some changes that don't affect C-axis stuff

Keep in mind that either config is quite complicated, and there are still a number of functions/features I haven't finished:
- Collet closer position sensor logic/interlocks for both main and sub-spindles
- GUI view rotation for sub/main spindle work
- Other stuff yet to be discovered

Your pick.

The M1 button is the one i am actually missing in Gmoccapy.
The space constraint is a hard one, everybody has other needs.
For me personally i would rather skip the full screen toggle, but a total of 11 buttons would fit as well.
 

This recent commit has me suspecting that it is in some way related to non-trivial kinematics.
github.com/LinuxCNC/linuxcnc/pull/3890

I use M1 option stops all the time, to give me time to check things on a new program before continuing to the next thing. This is still implemented on my mills old Gmoccapy installation.

Did turning on/off stops on M1 really get deleted from Gmoccapy? That would be disappointing.