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KMotion/KFLOP Test Version 4.35c Released
Many new examples, features, and fixes!
New Probing Screen Set (thanks to Jeremy Brown and Stigoe) see related Thread
https://youtu.be/LtXcO-KsMTk
Chip - Visual Basic CNC Program Thanks to Rick Caddell
https://youtu.be/Z6DaY6zFw18
New Advanced Trip State Blending
https://youtu.be/LdkyiH-v_9A
Full Change List Here
Download
Great work Tom. How is this "third order trip state" feature used? Are we able to control jerk on interpolated moves yet? Would love to see that feature.
Hi Murray,
Thanks. The 3rd order blending applies to independent axis motions. Previously if the destination or constraints were changed while a move was in progress only simple cases (basically far away from destination) were handled optimally. More complex cases would stop, then move to the new destination. Now optimal trip states should be determined in all cases. Also a blended move with different acceleration and deceleration can now be commanded with the new MoveEx function.
But no this doesn't apply to multi-axes coordinated motions. That is extremely complex.
To bad its a hard one, would be nice feature to have. Even the cheap Chinese 3d printers allow you to tune jerk these days, and seems to make big difference to performance.Quote:
Originally Posted by TomKerekes
I would still love to see that low pass filter added right into the trajectory planner someday too, without needing to use the transform feature. I havent been doing as much 3d toolpaths lately, but it would be a big help for this type of work.
Thanks again for all the work you put into this.
Hi Murray,Quote:
To bad its a hard one, would be nice feature to have. Even the cheap Chinese 3d printers allow you to tune jerk these days, and seems to make big difference to performance.
Do you have a link to a 3D printer with Jerk limits? The ones I've seen use the term loosely. Its actually a speed limit where the printer will slow down to that speed before changing direction instantly - which is quite different.
Hi Tom, I just did some searching and you may be right, looks like some just use this term for start speed or maximum instant speed change, which of course is completely different. I dont know if all machines work this way, or if some really are changing actual jerk (rate of acceleration change). This is very disappointing to see them using the term wrong like that.Quote:
Originally Posted by TomKerekes
Im fairly new to 3d printing, just bought a sidewinder X1 a month or so ago and it seems to be working surprisingly well with stock settings so I havent tried adjusting jerk on mine, cant even confirm if it even has the option to change it, or what it actually changes. I will experiment someday and let you know what i find.
Its probably way over my head...but ive always been curious, what makes the calculations so complex? I understand velocity is first derivative of position, acceleration second, jerk being third. And you obviously have the first two figured out and working great, why is the third step so complicated? I was hoping it could be just one extra step of whatever calculations you are doing now, but I guess its not that easy?
Hi Murray,
That's a good question. I don't have a good answer. Google "3rd order trajectory planning". Its vastly more complex. Path smoothness isn't sufficient to avoid infinite jerk. Constraints of continuous velocity and acceleration between segments means what is done in one segment greatly impacts what needs to be done in others. Try it :)Quote:
ive always been curious, what makes the calculations so complex? I understand velocity is first derivative of position, acceleration second, jerk being third. And you obviously have the first two figured out and working great, why is the third step so complicated? I was hoping it could be just one extra step of whatever calculations you are doing now, but I guess its not that easy?
Yeah it does seem very complex. Out of my league thats for sure. Too bad, I was kinda hoping to see this someday but I guess it isnt really an option. I guess realistically only small percentage of users would even notice and appreciate the change anyway.Quote:
Originally Posted by TomKerekes
Still love this Dynomotion system as it is, thanks again for everything you do Tom.
I noticed pretty fast changing from a jerk limited control to kflop but my machine is relatively large and heavy (table and saddle are over 1500lbs) with motion parts that probably weren't optimal without jerk limiting. That said, for almost everything I have done since the retrofit it hasn't been an issue. Some programs run a little slower than they used to, some are actually a little faster (where the old control would choke on small 3d segments at anything over 30ipm). The most significant increase was ~10 mins on a 4hr long program on the old control.Quote:
Originally Posted by mmurray70
I use my machine to derive my primary income and what I gained was not having to worry about 25 year old hardware dying at the worst possible time; well worth the trade off IMHO.