I think 250 lines a head rings a bell On Wed, Aug 18, 2021, 1:49 PM Feral Engineer <theferalengin...@gmail.com> wrote:
> I'm curious what the current level of block lookahead is on lcnc compared > to commercial controls. Anyone know the amount of data buffering that it > can handle? > > Phil T. > The Feral Engineer > > Check out my LinuxCNC tutorials, machine builds and other antics at > www.youtube.com/c/theferalengineer > > Help support my channel efforts and coffee addiction: > www.patreon.com/theferalengineer > > On Tue, Aug 17, 2021, 9:36 PM Sam Sokolik <samco...@gmail.com> wrote: > > > It would be the same setup... Just using servo amps.. Velocity out of > > the pid - position back from the encoders. > > > > On Tue, Aug 17, 2021, 8:14 PM andrew beck <andrewbeck0...@gmail.com> > > wrote: > > > > > Not sure Sam. > > > > > > I have a 7i77 on this mill though also. So analog control > > > > > > On Wed, Aug 18, 2021, 12:51 PM Sam Sokolik <samco...@gmail.com> wrote: > > > > > > > I am going to ask a stuid question.. If you have a velocity run step > > gen > > > > with pid. Couldn't you hook a limit3 between the pid and steghen. > > > > Because the input is velocity instead of position - wouldn't the > > > > acceleration limit in the limit3 be jerk instead of acceleration? I > > am > > > > sure it doesn't work that way.. I was just thinking you have moved > the > > > > derivatives up one.. > > > > > > > > (I can tell you it doesn't seem to work in practice - probably > because > > > the > > > > pid will always try to correct the error. Like maybe you would need > to > > > > negate the limit3 amount on the feedback side..) > > > > > > > > On Tue, Aug 17, 2021 at 1:28 PM Scott Harwell via Emc-users < > > > > emc-users@lists.sourceforge.net> wrote: > > > > > > > > > I haven't tried it yet, but this looks promising. > > > > > LinuxCNC S-Curve Accelerations > > > > > > > > > > > > > > > > > > > > Scott H > > > > > > > > > > > > > > > On Tuesday, August 17, 2021, 12:57:06 PM CDT, Ralph Stirling < > > > > > ralph.stirl...@wallawalla.edu> wrote: > > > > > > > > > > I've also been hoping to see this appear in a Linuxcnc update, > > > > > as it has been worked on by a number of people for years. > > > > > Here are the most recent threads about jerk-limited trajectory > > > planning: > > > > > > > > > > > > > > > > > > > > > > > > > https://forum.linuxcnc.org/24-hal-components/40152-jerk-limited-trajectory-planner-hal-component > > > > > > > > > > > > > > > > > > > > > > > > > https://forum.linuxcnc.org/38-general-linuxcnc-questions/34666-c2-smooth-velocity-profile?start=0 > > > > > > > > > > -- Ralph > > > > > ________________________________________ > > > > > From: David Berndt [ber...@uberwin.com] > > > > > Sent: Tuesday, August 17, 2021 9:01 AM > > > > > To: Enhanced Machine Controller (EMC); andrew beck > > > > > Subject: Re: [Emc-users] jerk control > > > > > > > > > > CAUTION: This email originated from outside the Walla Walla > > University > > > > > email system. > > > > > > > > > > > > > > > I don't have a great need for it with my machines, or the > time/brains > > > to > > > > > implement it. It just seems like a feature we really should have. > > > > > > > > > > I'd be willing to participate monetarily in some sort of system > to > > > > > incentivize the inclusion of jerk control. Perhaps an open-source > > > feature > > > > > bounty? Does the community want to consider that sort of thing? > > > > > > > > > > -Dave > > > > > > > > > > On Mon, 16 Aug 2021 23:06:05 -0400, andrew beck < > > > > andrewbeck0...@gmail.com> > > > > > wrote: > > > > > > > > > > > hey guys > > > > > > > > > > > > I am sitting here watching my cnc mill atm its shaking quite a > bit > > > > > > acceleration is 600mm/sec2 which is not that high i think. > > compared > > > > to > > > > > > every other cnc mill i have used with a commercial controller. > > they > > > > have > > > > > > jerk control and work much better. so looking forward to when we > > get > > > > > > jerk > > > > > > control here on linuxcnc! > > > > > > > > > > > > but in the mean time i need a poor mans jerk control and thinking > > of > > > a > > > > > > limit on the pid output to chop down the initial acceleration for > > the > > > > > > first > > > > > > moment in time just so little moves don't shake it to death > > > > > > > > > > > > andy mentioned that I could maybe use a limit component to limit > > the > > > > > > initial acceleration for the first tiny moment in time to cut > down > > on > > > > the > > > > > > vibrations. > > > > > > > > > > > > how do you guys think that could work? > > > > > > > > > > > > Regards > > > > > > > > > > > > Andrew > > > > > > > > > > > > _______________________________________________ > > > > > > Emc-users mailing list > > > > > > Emc-users@lists.sourceforge.net > > > > > > > > > > > > > > > > > > > > > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=04%7C01%7Cralph.stirling%40wallawalla.edu%7C7457b9607a2d4747a1e508d961a1b508%7Cd958f048e43142779c8debfb75e7aa64%7C0%7C0%7C637648169423748846%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=ue%2BwIaVhfay08NBevlCAvyOoNp0qVz9ojUuigRuCOOs%3D&reserved=0 > > > > > > > > > > > > > > > _______________________________________________ > > > > > Emc-users mailing list > > > > > Emc-users@lists.sourceforge.net > > > > > > > > > > > > > > > > > > > > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=04%7C01%7Cralph.stirling%40wallawalla.edu%7C7457b9607a2d4747a1e508d961a1b508%7Cd958f048e43142779c8debfb75e7aa64%7C0%7C0%7C637648169423748846%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=ue%2BwIaVhfay08NBevlCAvyOoNp0qVz9ojUuigRuCOOs%3D&reserved=0 > > > > > > > > > > > > > > > _______________________________________________ > > > > > Emc-users mailing list > > > > > Emc-users@lists.sourceforge.net > > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > > _______________________________________________ > > > > > Emc-users mailing list > > > > > Emc-users@lists.sourceforge.net > > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > > > > > _______________________________________________ > > > > Emc-users mailing list > > > > Emc-users@lists.sourceforge.net > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
