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TangentAudio wrote:

Reverse motion might open up the door to replicating the "Traking" feature on Prototrak CNC lathes. It lets you use one of the MPG wheels to move forward or reverse through the program motions.

The existing LinuxCNC TP already does this, if you set the feed override negative, it runs backwards. 
This was introduced for spark-eroder applications. 

Grotius wrote:

This can be true, i believe you. But what is accepted by the community? A arc blend or a clothoid blend.
If a product has corner with a arc blend, it looks quite nice. If its a non arc shape, i think they are not happy.

Apple make a special point of having G2(?) continuity on their products. The corners of an iPhone are not arcs, and people generally think this looks better, even if they don't notice it. Similarly on vehicles, they aim for better continuity so that you don't get straight lines in the reflections.

I found this YouTube video absolutely fascinating on the subject, and I did wonder if the matrix equation shown could be expanded to 3 or 9 axes to solve for the required continuity for CNC use. I think that would be a case of choosing the right boundary conditions and possibly solving iteratively.
(Don't be worried that the video is so long, if you are anything like me you will get to the end thinking it's been 15 minutes)

Nonsense deleted

@Automata,

Thanks for your gratulations !
It looks finally we made some progress on the scurve planner. Altough there is a lot to be done.
And there will sure be problems in the future, during testing on high speed machines. But we
can just solve bug by bug.

This document you linked is very nice !.
I there anyone who can help setup the formula's to create the curve's?

Now the planner can do 3d fillets and chamfers, we can just add the clothoid curve function.
The planners infrastructure is ready to add a hal pin to enable clothoid curves.

Also the video with G2 continuity is nice to watch.

1.I tried different methods, the video 1 shows that the tooltip do not show in qtplasmaс, but in the system utilities the tooltip was showing.
2. I sometimes need this when I'm creating part arrays and want to zoom in to see if the parts are overlapping
3. no, it doesn't cause any errors, it looks like the button turns on and immediately turns off the probing function, maybe need to add a delay between turning on and turning off the button.

I have a plasma with pneumatic Ignition, analog of hypertherm, and I did not notice any interference.

Hi,

The fillets are working.

Options during program run :
- use fillets or chamfers.
- Set a G0 fillet size. The rapids can also do fillets.
- Set a G1_G2_G3 fillet size.

So what i learned so far is :
When lcnc loads the gcode line by line at runtime, i add one emtpy line after each loaded segment.
During the program run, buffer is also emptied and new lines are added when using bigger programs.

Then when loading is finished and program run's, it just run's over the empty lines.

Then at runtime the fillets are calculated by the 3d cavalier algo.
It only creates a fillet for your current line & next line.
So it does not fillet the whole path in the same plane, as this would be very nice.
This is too compute expensive to fit in the cycletime and a lcnc signal eleven will occur.
So to minimize the computations, i only did one fillet at a time.

The 3d cavalier algo creates a plane from the current 2 gcode lines. Then it projects the 2 lines to a top view plane,
called the zero plane.
Then in top view the 2d cavalier algo is performed. When this is done, the 3 lines (including fillet) are transformed back
to original position. I think this is a clever method, also for future curves like clothiods etc.

Have fun to watch the fillets at work. Also switching to chamfers & using different fillet values at runtime.

It works in general, for most people. We will need a lot more information to say why it isn't working for you.

For some reason my browser is refusing to view the imgur link, And I don't feel inclined to force the issue given that you are newly signed-up user and this seems to be your first post...

How have you installed LinuxCNC, which Debian version? Which realtime kernel?

If you have a working Debian installation then you can try installing the realtime kernel separately, directly from the Debian repositories.

Search for linux-image-rt in the Synaptic package manager.

"EOF in file" is what LinuxCNC says when it can't find the subroutine file, generally a problem with the SUBROUTINE_PATH.

I am not familiar with the gcode python module, but I wouldn't be surprised to find that the last parameter that you have as an empty string is meant to be the INI file where the parser can find the SUBROUTINE_PATH info.

Maybe post some pictures of the whole affair as that would give us an idea of what we are talking about.

If the data can get into HAL then the rest is just scripting. I think this sounds like a job for a Python component:

linuxcnc.org/docs/stable/html/hal/halmodule.html
linuxcnc.org/docs/stable/html/config/python-hal-interface.html

This does assume that you know Python, or can persuade someone to write it for you. Though someone has created an AI chatbot that does a really decent job of this in the specific LinuxCNC context.
sourceforge.net/p/emc/mailman/emc-develo...mx-bs11/#msg58732428

Thanks Mate you are alway an inspiration
Cheers

Here is the current state of the kinematic model, which also contains the math to calculate the orientation of the end effector:

 

I believe the only way to do 3d arcs in gcode (outside of the 3 main planes) is to either do it in CAM and create short straight segments (which may be problematic given that the trajectory planner falls back to 1 line look ahead for any move involving more than XYZ axes) or do the plane orientation in our custom kinematic.
I have done some work in implementing a tilted work plane (TWP) feature for tool-rotation kinematics (which works quite well) and have been working on doing the same for my melfa 6axis robot. I had to abandon 'genserkins' out of lack of understanding and create my own kinematic with twp parameters built in. I have not ironed out all the bugs but the TWP feature looks promising. The path below is the result of just four lines of gcode:
 

 

The next hurdle for welding would be to modify the kinematics so the C axis (ie wrist rotation) is done in joint mode (to be able to keep the torch pointing to the center of the arc) instead of doing it in world mode like the position.

So basically you would define the tilted work plane by teaching in the 3 points as in the video (which I have already implemented in my 5axis TWP work) and calculate the center of the arc from the same 3 points.
Mind you all of this would only give you circular (and helical)  arc moves which would not let you weld, for example, a pipe joining another pipe.

Grab a bookworm netinstall iso.

Install XFCE desktop.

Then install Linuxcnc.