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Hi all, I'm working on moving from an older (Linuxcnc 2.8) Axis config to a Probe Basic config after getting a new spindle for my router.

I have successfully gotten the basics working and have even gotten the ATC functions mostly where I want them. (Huge thanks for the the starting point that is the Probe Basic screen set and all the macros)

I am running into trouble integrating my XHC-WHB04B-6 pendant. It works just how I want it to in the old Axis configuration, and in fact that configuration runs just fine under Linuxcnc 2.9 and the pendant works in that config.

However, in Probe Basic the pendant produces stuttery motion when jogging both in step mode and in continuous mode. It also will not register all pulses or clicks of the jog wheel when the wheel is spun quickly. If I slowly click the wheel in step mode (say 1 click per second) I get each step translated into machine motion, but if I quickly spin the jog wheel, I will only get a small fraction of the wheel clicks actually translating into machine motion.

General info:
-  What Linux OS being used including kernel type?
> Debian GNU/Linux 12 (bookworm)
> Kernel version: 6.1.0-44-rt-amd64

-  What version of Linuxcnc is installed?
> 2.9.8

-  What version of QtPyVCP and Probe Basic is installed?
> Probe Basic version: 0.6.6

-  How did you install Probe Basic? Quickstart guide? Dev Guide? 
> Probe Basic APT stable install following the guide here: kcjengr.github.io/probe_basic/index.html

-  Have you gone through your ini and hal files and compared to the sim config files to make any changes needed?
> Yes, Probe Basic is functioning, just the integration with the pendant is giving me headaches

-  Have you added all of the necessary files in your config folder that probe basic needs to run?
> Yes

I attached the hal files ini files and pendant hal files for the two configs. (note i renamed the pendant.hal file for the Odroid config so that there were not two of the same file name)

Please take a look and let me know if more info will make the problem easier to diagnose.

Thanks!
 

You need two network cards for that, no switch.

Rod, i refrained from giving up such info.

tommylight wrote:

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But we have 18% HCl and 25% H2SO4 anywhere... and you can buy ammonium nitrate in 50KG bags for 20 Euro! With no permit or any paper!
I can not build a hobby rocket nor get rid of the bugs (every spring tiny flying ants, by the millions), but blowing up half a city is easy!

Just add diesel and perhaps a detonator and you will be golden! I once watched (from a distance) mud blown out of a dried up water hole with 6 bags of nitram fertiliser and a small stick of gelicnite to hold the detonator and the results were spectacular! Even more amazing was the guy was actually was still live. He hid behind a tree and fired the detonator with the battery from his tractor and a far too short (for me) roll of electrical cable. Car sized blobs of mud beside the hole!

 Hello. Recently I’ve had problems controlling XYZAB because in fact I have two YY motors, so I need 6 Stepgens to avoid some issues I was having.  I added a 7i96s card and a switch, and added 10.10.10.11 and 10.10.10.12 in the Ethernet connections, also with gate 8. I’m not sure how to proceed with the ini/hal changes, tried some ideas around adding a second card IP, card1 read and write, and others, but no matter how, I couldn’t power up the system with both cards. Is there a base config o could work with to have both cards working? Any tips in having both cards working? I can ping both IPs, but I’m not sure if i won’t have other connectivity issues. Thank you in advance.

You are welcomed, always.

By the way, this is the HAL and COMP I have gotten working to control the turret.

 

"On second thought, in this kind of project I might use nested PID" that sounds super fancy, but I see two problems with it for me. For one, I would not know where even to start implementing this. And second, the motor RPM that I get is way too inaccurate for PID to effectively work.

I get the value from a 4–20 mA current from the VFD. I then have a 470 ohm resistor very close to my 7i84 that has the ADC to give me the signal I then process to get an RPM. The signal is rock solid, with no noticeable jitter at all, but it is only an 8-bit ADC, and my voltage is between 1.7 V and a little over 9 V, using less than half of the ADC range.

For getting an approximate gear ratio, this seems fine, but not for actual speed control, at least that is what I think. I may very well be wrong.

The feedback that I used for the spindle is an encoder on the spindle, so I am very confident in this feedback being good. The stuff I am doing with the motor RPM I really do not trust too much. The encoder also has an index, so threading is possible. I don’t want to change that either.

As to “This still leaves you to have to measure the adjustable gearing ratio between spindle and motor for properly scaling the speed command,” the variator is infinitely adjustable. That is why I think even a not completely accurate motor RPM and a really accurate spindle RPM to calculate the gearing ratio every servo cycle would do the trick.

So in a sense, this would only scale the error, as in: if commanded is 1000 and feedback is 800, the error would be -200. Now let’s say we are close to 1:1, then that does not really change, and we actually want the motor to go 200 RPM more.

Let’s say with the same commanded and feedback but a ratio of about 2:1—in that case, we need only about a 100 RPM change on the motor, so scaling the error with the ratio should do that. And as it is just a factor, it will never wildly change the system.

I am sorry if that makes sense only in my head. I have been banging my head against a wall here for some time now.

Regarding my problem 1, I think I have found the reason why the output is between 3000 and -3000. It is this line: [HMOT](CARD0).pwmgen.05.output-type 1
If I read the documentation correctly, it has to be:[HMOT](CARD0).pwmgen.05.output-type 0 to be 0 to 3000. I will see if that helps tomorrow.

On second thought, in this kind of project I might use nested PID:

The inner PID gets its feedback from the motor RPM, its command from the outer PID, its output drives VFD hz command. This PID has to be tuned first, testing it by manually commanding it in motor RPM units.

Next, the outer PID. This gets its feedback from the spindle RPM, its command from LinuxCNC spindle speed command, then its output commands the inner PID.

Am I correct, thinking this will automatically compensate for gearing changes? Except forward/reverse gear change if it exists which would need to be handled by reversing the direction of the outer PID.

Wow! That worked! Thanks so much!

Dudelbert wrote:

I may have not explained what I am after very well. With the variator, if we are properly tuned at 1:1, we would get a problem, as with, for example, 2:1 the same tune would overshoot massively, and with 1:2 we would undershoot.

So what I want is to measure the motor RPM and spindle RPM to get the transmission ratio and scale the PID error accordingly to have a similar response to the point at which it was tuned. I am not after controlling the motor RPM directly.

But to know if this will work or not, I have to get the tune at one point right first, see problem 1 of my previous post.

Just to clarify where your spindle speed PID feedback comes from:
1. Are you using motor RPM for feedback? I think that would be the proper way to do it.
2. Are you using spindle RPM for feedback? To regulate commanded spindle speed? I'm not sure whether there is any easy way to tune that. It seems your tuning would have to change dynamically with the gearing ratio, causing multiple complications.

If I'm correct, ideally the scaling from spindle RPM to motor RPM should be on the PID command signal. At that point the gearing affect on PID tuning should only be mechanical.

This still leaves you to have to measure the adjustable gearing ratio between spindle and motor for properly scaling the speed command.

Its possible but a little awkward do make new firmware with older PKTUART versions
because you need to copy files around to do it.

Can you update to current LinuxCNC  (2.9.8)

If not I can look into automating the PKTUART versioning as is done for most
modules but that is a fair amount of work.

Note that the full source is available in the 7I96S.zip file

here  is complete setup for 250us position control loop ... with internal homing subroutine and internal probing input mapping for internal precision homing ability... you can select more methods of homing ... pos, pos + latch, neg, neg + latch ... but carefully map everything 

just enjoy !

Hello endian,
thank you very much for your reply.
The AX5201 is working fine now. I didn't read your desciption of your conversion tool carefully. So I exported the "Startup.xml" manually from TC3 and assigned it also manually in ethercat-conf.xml. With the parameters "complete -i" this is done automatically and works fine.
Thanks again!