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I am not in the shop now, but in short, the "pressure" motor is
-a 3 phase BLDC motors with it's own electronic controller taken out of the old photocopiers,
-there are many versions and sizes of them,
-form 5 to 10 pins,
-all signaling is sinking type or "active low", meaning connect to ground to activate
-all have the pinout printed on the board,
-older ones are pure PWM while new ones require also a clock signal,
-some are single direction while some are bidirectional,
-and most of them can be easily used for this purpose/machine,
--The PWM ones require 5V, 12-24V and an inverted PWM signal
--The ones requiring clock signal have a self check feature, so mostly work with only 12-24V supply and one of the pins tied to ground, this pin will spin the motor for about 2 second and stop, and has to be disconnected and reconnected to spin again. This pin is used as inverted PWM but scaling must be set to about max 85-95% PWM to keep the controller from tripping and stopping the motor after 2 seconds.
--for inverting the PWM pin i use a single 220 OHm resistor and a single transistor, any NPN transistor works, resistor connected between base of transistor and PWM output from PC or Mesa board.
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hackaday.io/project/5236-savin-c2020-teardown

@Rosalyk,

And I wonder why this planner is needed at all if I still have to calculate the circle myself.
Yes, that's work of the planner. It should at least work with lines & arcs.

 

Hello everyone,

thank you very much for your continued help
In the next step I would like to try to set up the RTAI kernel.
Is the following procedure correct?
1. install the "normal" Linux CNC from the homeage under Download
2. download the RTAI kernel at linuxcnc.org/downloads/ at the bottom of the page
3. open a console in the download folder
4. install
sudo apt install ./rtai-modules-5.4.258_5.3.3-linuxcnc-delta_amd64.deb
sudo apt install ./linux-image-5.4.258-rtai-amd64_5.4.258-rtai-amd64-2_amd64.deb
5. restart
6. check if successful
Open console
uname -a

edit

Unfortunately, it didn't work out that way.
Are the header files missing?
It worked but i had to select the kernel in bootmenu
 
still bad

how can i check which linux cnc version i use? as i understood it should be the rtai?

@Andrew,

Nice work!

With scurve jogging you can jog faster because you can use higher acc profile. But its problably also
more dangerous jogging at such high speeds.

For a servo driven machine with a lot off mass, scurve jogging will be a used more often as it reduces
machine shocks, cq inertia.

But indeed if you jog normal speeds, trapezium jogging is fine, and in practical sence, it feels
more direct.

Hmm, it looks like this is coming to zero velocity and acceleration at the end of each segment instead of getting up to the highest velocity the segment can get to, and the next segment starting from that velocity.
Ahh ok.

I modified the example to do 100 x 1 inch segments without stopping in between.
It works ok.

I was checking here when it happened so i was left staring at a white page with very small letters at the top left!
Thank you.

Sorry about the down time, I was updating the OS when I lost connectivity and it remained stuck until I could log back in and finish the dist-upgrade.

JT

I think I've fixed all the bugs that I know about so far. Here are 100 randomly generated segments. Some places look like sharp edges, but it's just scale. When zoomed in they are all smooth s-curves.

I'm pretty sure this can also be used for velocity mode and jogging too. The more expensive functions take about 5200ns, and the ones that would be needed for jogging take about 1200ns. I was thinking though. Isn't using s-curves for jogging kind of pointless? You're not cutting anything while jogging, and if you are, you're cutting straight lines, so there is no benefit, just added complications.

 

Yes, I know canon = StatCanon(...) but what does StatCanon do?

JT

Actually I believe that another user referenced perhaps the same issue here .

Are you using the auto tool length probing on your machine?

Not sure what you are referencing here?

If you look at the picture of my machine in this post you can see what I call a "Tool Length Sensor", I believe that's correct CNC terminology.
I also have a touch-off plate but I have not got that to function properly with my 7i76e. I know that my spindle is properly grounded at both ends so I believe that all I need is one wire connected to the plate and I should be able to touch off with the plate.

What I am trying to achieve is the ability to machine a part, remove it from the table and then later machine it again without losing my initial coords.

Regards
Andy

@Andrew,

Here is the scurve doing 100 segments:

Hmm, it looks like this is coming to zero velocity and acceleration at the end of each segment instead of getting up to the highest velocity the segment can get to, and the next segment starting from that velocity.

Hello, I am new to Linuxcncn and I have successfully run the ethercat servo driver. I have been trying to homing 10 days, I have never succeeded. Please, if you can explain it a little more clearly, with pictures or text files, as if you were explaining it to a beginner, I would be very happy. I have been trying day and night for a week, but I have not succeeded. have a nice day . I write to Google Translate

As Aciera suggested, you must use "sudo" when launching the
editor to edit system files:

$ sudo nano /etc/default/grub
 

That typo has been fixed. Download a fresh copy and reinstall.

JT

Judging by the pdf I think this is correct, not sure about the initial null though

"biss_chan_0=null%1bcrc%6fwarning%1berror%1bzero%2uencoder%24e"

(the added "zero" is for the zeros bits in the 26 bit position code"

It started working again soon after I posted the above. (Then I went on vacation and forgot to update the thread.)