On Sunday, November 12, 2017 at 3:39:34 PM UTC-5, Daren Schwenke wrote: > > What I would have expected to be the solution would have been setting > initial homed position with a negative Z value, like this: > [TRAJ] > HOME = 300 250 -300 > When I do that and home though, the resulting position Z position is still > positive, and kinematics is still not inverted. > If you are like me, you probably didn't even know there was a HOME under > TRAJ, cause it's ignored for trivial kinematics, and not used for many > others. > I followed the value though, and it does still end up getting used: > > https://github.com/machinekit/machinekit/blob/314246595127ddc2dc08bb0f8a9e8606260e1679/src/emc/ini/initraj.cc#L230 > > Setting the [AXIS] HOME positions negative always results in immediate > following errors. I suppose negative length arms doesn't make any sense. > > Flipping one or more of the tripodkins.Bx,Cx or Cy values ends up > inverting some axis, but not Z. > > If no-one has any ideas, I'll just make a new kinematics module which is > always inverted. Seems like a waste though. > Did this, it works now. This taught me how far off I really was on some of my parameters. Way off... Maybe far enough off to cause tripodkins to not invert on it's own. Perhaps.
> > On Saturday, November 11, 2017 at 6:10:32 PM UTC-5, Daren Schwenke wrote: >> >> I posted the result, not the cause: >> >> https://github.com/machinekit/machinekit/blob/314246595127ddc2dc08bb0f8a9e8606260e1679/src/emc/kinematics/tripodkins.c#L202 >> >> >> >> On Saturday, November 11, 2017 at 6:01:17 PM UTC-5, Daren Schwenke wrote: >>> >>> I have been searching for a while for how to implement tripodkins. Got >>> that sorted, but it's made for struts and not cables. So I actually need >>> inverted tripodkins. >>> >>> Real word the non-inverted tripodkins translates to the opposite >>> compensation occurring. A Z axis coordinated move in the center towards the >>> bed causes the steppers go slower as they are further from the bed. For >>> the same vertical rate, I believe the opposite should be happening. >>> >>> Best I saw online, anywhere for reference was this: >>> https://psha.org.ru/irc/%23emc/2006-07-09.html >>> I implemented that and it works, but of course it ends up not inverted. >>> >>> https://github.com/Arcus-3d/Arcus-3D-C1-BeBoPr/commit/c70258aeaa05a42f8b93c55bf4b650db19091e4c >>> >>> I see a flag in the code for being inverted, which* looks like it's >>> triggered by negative Z* from the other kins. >>> >>> >>> <https://groups.google.com/forum/goog_563650889> >>> >>> https://github.com/machinekit/machinekit/blob/314246595127ddc2dc08bb0f8a9e8606260e1679/src/emc/kinematics/tripodkins.c#L167 >>> >>> >>> >>> >>> So I've tried changing the signs of various things for a solid day in my >>> ini in an attempt to get it inverted, but haven't had any luck yet. >>> Some result in joint following errors, some result in negative axis >>> values, but none seem to invert the kinematics. >>> >>> Short of re-compiling to manually flip it in the source, some guidance >>> would be appreciated. >>> >>> >>> -- website: http://www.machinekit.io blog: http://blog.machinekit.io github: https://github.com/machinekit --- You received this message because you are subscribed to the Google Groups "Machinekit" group. To unsubscribe from this group and stop receiving emails from it, send an email to machinekit+unsubscr...@googlegroups.com. Visit this group at https://groups.google.com/group/machinekit. For more options, visit https://groups.google.com/d/optout.
