A few quick tests to try to narrow this down: 1. Does running the same command with G61 fix the issue? 2. In G64, if you call a subroutine via MDI that does multiple moves, is just the last move at reduced acceleration? 3. Does the last move of a program accelerate slowly as well?
If the answer to some or all of these is yes, then it might be the trajectory planner's blending behavior. In G64 mode, incoming motions to the trajectory planner are blended with parabolic blends by default (the old linuxcnc 2.6 and earlier method). Parabolic blending works by dropping accelerations of segments to 50% of max, so that prev / next segments can be run simultaneously without violating acceleration constraints. Unfortunately, the last motion is stuck waiting for a "next" motion that will never come, so it ends up at 50% of max acceleration. The fix for this is not trivial, but you may be able to work around it by doing your testing in G61. -Rob On Thu, May 16, 2024 at 8:58 AM Todd Zuercher via Emc-users < emc-users@lists.sourceforge.net> wrote: > Maybe I spoke too soon. I did a little more searching and found that > there is an issue with MDI commands that they are executed with half of the > acceleration of the settings. Is this intentional for some reason, or is > it a bug? > > I confirmed with this machine that yes, regular G-code programs and > jogging moves use the correct acceleration limits, but MDI commands only > use half. Why is that? 2.7 didn't have this behavior. > > It kind of makes testing machine settings a pain in the... > > Todd Zuercher > P. Graham Dunn Inc. > 630 Henry Street > Dalton, Ohio 44618 > Phone: (330)828-2105ext. 2031 > > -----Original Message----- > From: Jon Elson <el...@pico-systems.com> > Sent: Wednesday, May 15, 2024 7:20 PM > To: emc-users@lists.sourceforge.net > Subject: Re: [Emc-users] Acceleration Settings? > > [EXTERNAL EMAIL] Be sure links are safe. > > On 5/15/24 12:23, Todd Zuercher via Emc-users wrote: > > I'm trying to figure out something goofy that seems to be going on with > my acceleration settings. > > I'm running Linuxcnc 2.9.0 and Axis ui. > > I have all of the max_acceleration settings set for 20.0 (and > stepgen_maxaccel = 25), and for some reason everything only moves with an > acceleration of 10 ipsps for G0 and G1 moves (confirmed with Halscope), but > jogging does go at 20. Is there normal behavior or am I missing some > setting somewhere that is limiting the acceleration? > > > In the latest LinuxCNC there are TWO places that have accel and max > velocity settings. Jogging is in the JOINT_x part, and CNC moves are in > the AXIS_x section. In general, you want the same settings in both JOINT > and AXIS sections. > > Jon > > > > _______________________________________________ > 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
