LinuxCNC S-Curve Accelerations

I revised the NC program and made the number of corners and the radius parameterizable.

 
 Thats a dodecadon lol
I was planning to make rounded corners actually be radiuses in the gcode G2 G3, probably next week, unless you want to oblige, many thanks again Rüdiger!

NC program.
square with parameterizable size and corner radius.
with G10 L2 R can be rotated around the C axis.
I don't have the knowledge to create an NC program with any number of corners and G2/G3 radiuses

github.com/grandixximo/linuxcnc

For whomever would like to help me test the improvements, download and build, this is not in master yet, still waiting for the halcsope to get merged, I have only tested on the scope so far, will do some testing on real hardware before sending a PR to master.
Would love to have some help testing, thank you all!

still in fixing a few things, don't expect the git history to stay

The arc interpolations need some work, G1 seems pretty good, will work on arcs next, maybe not ready for testing yet...

@grandixximo
Note the issues related to scurve code:
github.com/LinuxCNC/linuxcnc/issues/3719
github.com/LinuxCNC/linuxcnc/issues/3720

I'm not sure if pinging you on github works.

I get notifications, I do check on them when I am free...

Edit:

YangYang also replied, those will be fixed, but we have bigger fish to fry now, we are working on arc stopping, and some other arc blending related issues.

Does it compatible with mesa based setup ??

it is compatible with mesa default setup, but you need add the jerk parameters in the ini file, look at the axis_mm_scurve.ini file


I wanted some feedback from the community about s-curve, there a few considerations to make, not just jerk spikes

I think there are some choices to make, when trying to respect jerk limits, we can:

1 - Slow down at curvature changes: reduce Vel so the centripetal acceleration change is manageable. (this defeats high-speed machining)

2 - Modify the geometry: insert transition curves (clothoids, Bezier, splines) that have gradually changing curvature. This eliminates the discontinuity but changes the path. (when G64 Px is too small you will see jerk spikes)

3 - Accept the spike: the programmed path has a curvature discontinuity, so the motion will too.

There is no fourth option. You cannot maintain velocity, follow the exact programmed path, AND have smooth jerk. we need pick two.

My personal opinion is to default to #1. But as G64P tolerance increases allow more path tolerance so that velocity deviation can decrees.