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 <[email protected]> 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 <[email protected]> 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 < > > [email protected]> 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 < > > > [email protected]> 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 [[email protected]] > > > 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 < > > [email protected]> > > > 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 > > > > [email protected] > > > > > > > > > > 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 > > > [email protected] > > > > > > > > > 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 > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
