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My FT sensor is a multiple-axis sensor that mounts at the robot end-effector. Tool gravity compensation, external force, and new joint position command calculation are already done, so right now I need to send these commands to LinuxCNC.
Sending via the jog command does not give me a smooth move, I will try the jogwheel function by converting the position command to jog count, not sure if it works

Lately I started looking with great curiosity into LinuxCNC, because it seems to be one of the nicest and most affordable options to get EtherCAT and recently even s-curve acceleration control! In other words, as far as I know, it's the only solution on the market that offers such badass features as well as full configurability at a fraction of the price of other devices.
My current experience is with Mach 3 and UCCNC, but in both cases I was dissatisfied with motion planning where the machine would stutter a lot with complex toolpaths or with larger error allowance, it would run smoothly but it would mess with the surface finish.

My biggest hurdle right now is finding the right hardware. I saw countless solutions and configurations to get this done and I'm looking for something well proven that's not too hard to set up and doesn't look like spaghetti.
I was looking into Mesa boards, but even that got me a bit confused and I don't know what I should get. What's important for me is that the board offers screw terminals for interfacing with endstops and VFD and ideally it has its own computer - i.e. Raspberry Pi.
Could I ask someone for some recommendations? 

I've set up a few multi head gantry machines, but the ones I was working with had fixed spacing between the heads. I've set them up using Z and W for axis for two head machines. But for a larger machine I set up that used 8 heads I used the new extra joints feature and controlled them all with the Z axis command, with each joint having separate offsets for tool lengths and the ability to enable/disable each spindle/head and when one was disabled it automatically would park raised up at it's home position.

I've thought about dual head machines with two heads on a common X or Y axis a little bit and can imagine couple of ways to handle it. One possible way that I think has merit would be to configure both heads with a common X with a U axis set up as the spacing between the two heads. This way an X axis command would move both heads in parralel motion, and U commands would vary the space between them. To set up this, if the joint arrangement is such that the two axis joints are totally independent (say each head is driven by motor turning a pinion gear on a common rack on the gantry.) the kinematics model would be joint0 = X position, and joint3 = X+U and revers kins X=J0 and U=J3-J0.

The advantage to this set up would be that the g code for milling out 2 parallel identical parts could be simple 3 axis xyz g-code. (This could be a big advantage if the current version of Linuxcnc still doesn't do advanced look-ahead tool planning for axis beyond XYZ especially if UVW are left out. That used to be the case a few years ago but may no longer be true and was the reason I set up my machines the way I did to allow commanding multiple Z axis with just a Z command instead of using Z and W...

But If you would want to do something different with both heads simultaneously, like for example cutting out mirror images of the same shape at the same time one on XYZ and the other on UYW. Then it would probably be better to have simple 1:1 kinematics with J0=X, J1=Y, J2=Z, J3=U, and J4=W. However this will make collision prevention more difficult than the U=J0+J3 model.

i have actually learned quite a bit from this project to be honest. i have some big plans for this build. a conventional table and a rotary cutter have some very different needs, if all you need is to cut round tube then things can be kept fairly simple, but if you cross over into other profiles things can get quite involved. this project is one of those projects that take forever to get finished but once done you have something substantial.

I understand, but the file you posted is .HEX and not BIT, so to use it, as I understand it, you must use a PIC programmer. My question is: how is this procedure done?

Thanks Henk,

super useful!

Is the index Z pulse that you mention the R/-R signal on this table?

www.ditron-dro.com/product/ditron-high-p...g-machine-dro-tools/

Could you set it up as a probing move using the force torque sensor target value as the limit input for the probe input? Possibly using a comp hal component to compare the FT sensor output with the desired value.

(edit)
The tricky part would be if you would have to listen to the FT feedback from multiple FT sensors on multiple axis for a complex multi axis kinematic move. But if you only need to listen to one sensor on the end effector, or limit moves to single axis moves, the above should work. (I think)

ok?

Hello Hakan
Here are the results of both checks:

sudo service ethercat status:

● ethercat.service - EtherCAT Master Kernel Modules
     Loaded: loaded (/lib/systemd/system/ethercat.service; enabled; preset: enabled)
     Active: active (exited) since Fri 2025-05-09 13:44:10 CEST; 1min 16s ago
    Process: 542 ExecStart=/usr/sbin/ethercatctl start (code=exited, status=0/SUCCESS)
   Main PID: 542 (code=exited, status=0/SUCCESS)
        CPU: 29ms

Mai 09 13:44:10 roger systemd[1]: Starting ethercat.service - EtherCAT Master Kernel Modules...
Mai 09 13:44:10 roger systemd[1]: Finished ethercat.service - EtherCAT Master Kernel Modules.

sudo modinfo ec_master:

roger@roger:~$ sudo modinfo ec_master
[sudo] Passwort für roger: 
filename:       /lib/modules/6.1.0-30-rt-amd64/updates/dkms/ec_master.ko
version:        1.6.4 1.6.4.g703b611-1+17.1
license:        GPL
description:    EtherCAT master driver module
author:         Florian Pose <This email address is being protected from spambots. You need JavaScript enabled to view it.>
srcversion:     976B904C4EBCA2C98AAB9AC
depends:        
retpoline:      Y
name:           ec_master
vermagic:       6.1.0-30-rt-amd64 SMP preempt_rt mod_unload modversions 
sig_id:         PKCS#7
signer:         DKMS module signing key
sig_key:        0C:21:72:1B:F5:21:65:8B:7F:BF:48:64:17:62:5D:68:85:79:BA:BF
sig_hashalgo:   sha256
signature:      4A:E3:8A:17:F3:B0:9F:77:3C:AC:E0:3A:0E:17:7C:E5:BD:73:15:D5:
        8F:E7:72:79:94:A6:2E:EC:4D:F8:90:8C:9A:D3:02:F1:CA:78:59:46:
        5C:C6:5D:40:72:1D:E6:28:B9:F8:DD:C5:87:DE:C3:11:35:50:E7:EC:
        71:78:C7:43:5F:AE:E9:E1:11:FD:28:8E:58:2A:E8:38:AE:84:80:CE:
        BE:16:8A:8F:86:EE:68:3C:33:EA:39:0C:23:F6:C0:A7:CA:6F:95:BB:
        E2:72:1E:47:C4:62:82:4A:09:A2:7D:FB:3B:F3:7C:ED:E3:FC:8D:36:
        62:9F:47:0B:71:CD:04:8D:69:F6:D5:44:AD:A3:00:44:B5:5A:36:C3:
        CA:5B:E0:D5:B5:5A:50:C0:44:2A:42:63:7A:CC:8E:FB:DE:E7:21:1F:
        06:C9:6D:41:F3:60:3A:0A:AA:AE:4F:51:DF:17:17:0C:25:1D:C3:33:
        71:45:9A:5E:14:73:A9:4C:4E:D0:C4:70:DA:00:EA:57:6D:41:EA:63:
        A5:CE:8A:E4:9D:91:01:54:FC:EE:90:5A:FC:96:8A:94:FE:C4:8D:07:
        9C:8E:82:A8:5F:43:4F:86:49:8C:E6:0D:BF:69:D7:53:C4:5D:8B:C6:
        81:05:63:EC:0F:7E:F1:27:C8:FE:46:15:AD:C1:03:28
parm:           main_devices:MAC addresses of main devices (array of charp)
parm:           backup_devices:MAC addresses of backup devices (array of charp)
parm:           debug_level:Debug level (uint)
parm:           run_on_cpu:Bind kthreads to a specific cpu (uint)

To summarize how I installed it:
I followed the procedure described by rodw exactly. I didn't leave anything out, and I didn't add anything. I also lack the knowledge to do that. I've reinstalled the PC three times now, each time with the same result: Master0 link down. The network adapter settings are as I posted them (IPv4 Local Link and IPv6 disabled). UEFI is not active, and the installation itself didn't report any errors.

Sounds like you are describing a run away servo system. First thing to check is if the encoder feedback direction is correct. Make sure that spinning the motor in the positive direction moves the DRO in the positive direction.. Second need to check if the analog output signal polarity is correct. Make sure applying a positive voltage to the drive input turns the motor in a positive direction. Both of these issues can be corrected in software by making their scale values negative (neg. encoder scale or input scale and neg. output scale). Either of the above conditions can cause a runaway as you describe. However changing both at the same time will cancel each other out and leave you with the same problem.
other out

unknown wrote:

Warning: Spoiler!

Sorry I meant 2.9.4 Try not to get bogged down with latency. Test the machine running code, if it works don't worry too much about it. I took the gcode file that loads when you first start Axis, made it into a loop, loops thru the gcode about a hundred times,if I don't get any errors I'm confident it will be fine. I really don't think there will be much difference between a modular or monolithic kernel. You can gain a bit by fiddling with mount options, looking for any background services that aren't needed, I generally disable sound and I'll disable wifi if it's not required. You'll find this forum a lot different to cnczone, for one no one on here gets caught playing my rapids are this fast, also you won't here anyone saying that you need to be a programmer to use Linuxcnc. It works and works well. Almost any issues you have will have been discussed many many ten times over. 99.99% of the reason Linuxcnc won't start is a typo somewhere in the hal & ini files. Sometimes I think that running the latest kernel on older CPUs isn't the best course of action. Far better to have some extra latency and a stable system. Look you can spend a lot of time building different kernels and trying all the tricks in the book to lower latency, but as long as latency is, as a rule thumb, below 100,000 ns for an external step/direction generator you're good to go. Then again network latency can be a PITA to sort sometimes.

Yes i have Realtek card but i solved the problem with the r8168-dkms module.

 
Why in the kernel of linuxcnc why are hibernation and other acpi function active?
Is not  a problem?

The values for step & direction are part of the ini file and can be adjusted to suit many stepper driver products.
With a 25000 ns base thread motion will be based on this.
External motion control is usually based on a 1ms update period.

Hence the reason a known & steady latency is important, regularity is an important factor, like a band if the drummer isn't regular, uhmmm like Lars from Metallica, things don't work as well as they should.

Sorry I meant 2.9.4

Try not to get bogged down with latency.

Test the machine running code, if it works don't worry too much about it.

I took the gcode file that loads when you first start Axis, made it into a loop, loops thru the gcode about a hundred times,if I don't get any errors I'm confident it will be fine.

I really don't think there will be much difference between a modular or monolithic kernel.

You can gain a bit by fiddling with mount options, looking for any background services that aren't needed, I generally disable sound and I'll disable wifi if it's not required.

You'll find this forum a lot different to cnczone, for one no one on here gets caught playing my rapids are this fast, also you won't here anyone saying that you need to be a programmer to use Linuxcnc. It works and works well.
Almost any issues you have will have been discussed many many ten times over.
99.99% of the reason Linuxcnc won't start is a typo somewhere in the hal & ini files.
Sometimes I think that running the latest kernel on older CPUs isn't the best course of action. Far better to have some extra latency and a stable system.
Look you can spend a lot of time building different kernels and trying all the tricks in the book to lower latency, but as long as latency is, as a rule thumb, below 100,000 ns for an external step/direction generator you're good to go.
Then again network latency can be a PITA to sort sometimes.

can i connect the menu options on the position-logger application with the halpin on the AXIS controller so that i can record the position with an external button (parport input)?

some menus as in the picture