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Went through this twice, still have no clue what ...
We have a modern THC, fully implemented in LinuxCNC, including PID and closed loop and everything, with a bit to much added functionality for my taste. All made possible by Mesa THCAD.
Have a look at PlasmaC and QtPlasmaC, everything mentioned is already there and working properly, and much more.
THC has a single purpose: to keep the torch the set amount of height from the material while cutting.
Everything else are added features that a THC might or might not have, be it in software or hardware.
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Proma THC 150 SD is the stand alone version that intercepts step/dir signals from Z axis
Proma THC 150 sends UP/DOWN/ARC OK signals to PC, and the PC makes the moves, so not stand alone, and can be considered closed loop for sure.

Hi tommylight, i just followed the advice from PCW in an earlier posting: "...and change all joint PID "P" terms to 666"
OK, i will do that and also correct the stepgen max velocityto 160.
FF2 has been also an advive from PCW - I have Servos with integrated drivers, no feedback to the MEsa card.
"You might try plotting the following error and perhaps tuning by adding a little
FF2 (say .0003 to start) to the PID loop (using the calibrate menu so you can do this live) "
I'm just doing what I've been said to.
Thanks for your hints!
Greets Hanno

The best plasma controllers don't have a THC. Instead, the torch height control is done internally by the motion controller. Because the motion controller is all seeing, it knows when to apply anti dive and other corrections because it is THE MOTION CONTROLLER.

This is the approach Linuxcnc takes if you use QTplasmac plasma controller GUI. QTplasmac and its plasmac component take full control of the X axis so motion commands are only in the X,Y axes. In fact, any Z axis motion is stripped out of Gcode files when they are opened.

All you need to do is to feed Linuxcnc the torch voltage and it can use its robust PID routines to control the torch height. You can do this with a THCAD2 from Mesa electronics or in an Ethercat world something like a Beckhoff EL3162.

The THCAD2 is a voltage to frequency converter. It is connected to an encoder and the frequency is converted to a voltage inside Linuxcnc. The EL3162 reads the (divided) voltage directly.

There is a very high linear correlation between torch voltage and torch height so torch voltage becomes an ideal process control variable for torch height control. This is outlined in the Plasma primer in the docs. linuxcnc.org/docs/stable/html/plasma/plasma-cnc-primer.html 

The capabilities of Linuxcnc already far exceed anything from Centroid as the collective minds of open source provide much higher intellect than can be achieved by a closed team.
 
Open loop drives are ideal for plasma use because there are no irregular cutting forces so the system is perfectly predictable. A correctly designed open loop stepper system will use the enormous low down torque to provide high accelleration to minimize the times when corner lock is required. They will only loose steps if the original design is poor.

Linuxcnc does not care about what drives are in use as it just works in device units. Open loop, closed loop, analog, step and direction, ethercat are all the same once installed and configured.

That's a really nice improvement, can't wait until the next release to try it out.

Actually, having a small amount of FF2 improves the following error
(the actual amount should be the time between reading the position and updating the output
though 0.005 seems large)

It may be necessary to take a look at the following error to diagnose the issue
(this will also allow for tuning of the FF2 value)

Increasing the following error limits should not hurt either

Thanks for all the hard work Scott. The PIO install went really smooth, all I needed to do was update my ststm32 lib and it compiled no problem. Next steps for me is doing a H723 port, and figure out how this new repo works. Regarding hardware abstraction, (as always) I have notes on that based on the PIO stuff I did with Drew on the W5500 ethernet branch.


Hmmm call it something like Remora Motion Controller or something? ReMot? ReMOC? RemoraCNC?

Maybe GrblGru with this Extension:  ?

Maybe because I want to use the power of LinuxCNC for something that is not a mill. Like a pick & place machine that would adapt the position according to a vision result

Well, you can, but you need to use the python module.

Nice nice nice... This document is tasty and it is a new galactic space for everyone from us... 

Sinamics are widely used for everything and they are very powerfull.. 

every shared picture is are helpfull i think if you will need help I am here for everyone.. i will create a dry project in the twincat3 to check configuration ...

 

You have a servo period of 2000000 (2 million) but failed to set the correct P value for it at 500, not 666.
Max_velocity is 125 but stepgen_max_velocity is 150 despite just above it being clearly stated it must be 25% above max_velocity, so absolute minimum is 156.25, or rounded 160
And, why do you have anything but 0 for FF2 on a stepper system? It should be 0.
All of those contribute to your issues.

Hey guys, after several delays I got my machine running and I made my first part with it. First part, first problems. The locknut from my driven ball screw came loosened and I got a lot of backlash. I fixed that, then I had problems with my VFD (Hitachi WJ200), and had to send it to the service. Meanwhile, I used a chinese VFD (with filter unit in the line) , that worked fine, but last week I got the known problems with "motor-0-errors. Mostly if the x-axis stopped, turned around, then comes the error. Sometimes it runs several paths, then stopped again. That drives me crazy.
My latency is as good as before, I don't have lost packages, I don't know what to do with it.
Do you have any hints for me to change this problem? I put my actual HAL and INI here.

BTW - I don't understand that kind of error. What makes LCNC to give this error out? There's no connection to the motor's encoders, no feedback nothing what makes sense for me...

Tanks for any help!
Kind regards, Hanno
   

Try this:

unknown wrote:

I don't know where this idea comes from that you need any coding skills to setup Linuxcnc. This is one of the biggest lies ...

 

Sorry if it wasn't clear, my english skills must be just as poor as my coding; I'm coding a component to use TMC5160 drivers over SPI without any step/dir signal. What I wanted to say is that I'm sure I would have a working LinuxCNC configuration by now if I would just have bought a Mesa card. To me LinuxCNC is a bit more complicated to set up, even if you definitively don't need more coding skills than for FluidNC, which also have a config file.

I don't know why you would want to send a gcode file line by line to linuxcnc when it can open and read the file directly.

Maybe because I want to use the power of LinuxCNC for something that is not a mill. Like a pick & place machine that would adapt the position according to a vision result, or for a PUMA arm or any other automation machine in which a "master" would send g-code to a LinuxCNC slave to move the axis. OpenPNP is a good example and there already is an interface .

One thing that is very intriguing, you admit to poor coding skills, yet propose some major replacement of the Linuxcnc internal workings. 

I don't propose anything; I just have the feeling that if there is one area where FluidNC or any micro controller based G-Code interpreter is better than a computer based solution, it is for step/dir generation. There is no Latency-test in FluidNC, just hardware interrupts!   (But also, there is no encoder feedback, no routines, no special kinematics and many other no.)

Have a look at the angle jog component:
linuxcnc.org/docs/stable/html/man/man9/anglejog.9.html

ErwinCNC wrote:

Hello
I put my pi 5 into operation yesterday.
Unfortunately I get the locale error with Pconf

I tried to use the same settings as you.
My keyboard is german

Do you have an idea?
 

I *think* you have to set the localle etc from menu-config - mine was not set for me.