Trajectory Planner using Ruckig Lib

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)

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. 

Regarding toolpath smothing using clothoids in CNC application. I've posted this before in another thread but the link there seems broken so here it is again:
www.researchgate.net/publication/3318941...cf4408a7c0c/download

I just want to say, great work everyone! Just let me know where to send beer.

First of all this is super awesome watching the progress on this project!  a huge thank you to those putting the time in. 

I wanted to throw this out as this is where my issues arise from with machine shake, it occurs during adaptive cutting tool paths on repositioning moves where a series of short line segments are posted.  I have tried using smoothing settings and tolerance settings in fusion but it continues to spit out these short segments.  i use G64 with the P value tied to fusion 360's "smoothing" setting, and it helps slightly but the shake at these repositioning moves is terrible, the doors on the machine rattle and shake something fierce and im sure its awesome for the motion mechanicals.  I am posting the file and was wondering if perhaps you might be inclined to run it in your test TP and show a comparison of the current stock tp and the new scurve.  i have a video here showing the machine shake its pretty ugly..  it was cutting this part, if you have volume you can hear the shudder and if not watch the frames of the doors for the shake.. /o\

Thanks guys!

Chris

repositioning shake video

 

 
 

Hi Chris,

I will test the ngc file i the planner coming day's.

Hi All,

Found a nice lib, github.com/ebertolazzi/G1fitting .
This is from university.G1 fitting with clothoidsby Enrico Bertolazzi and Marco FregoWe are now a few commits ahead of the master.

I walk up to the morning sky first. With all my favorite colors. Right on. My sisters and my brothers.


Ok we made a function test in c++ to verify if we can use the bi-clothoid's into the linuxcnc toolpath planner.


The function peaks to :  0.094579000 milliseconds