On Thursday 31 August 2017 07:05:44 theman whosoldtheworld wrote: > seems really a confusion ... but not from XHC and acceleration, but > from velocity and acceleration ..... In fact, but it may be that I > lost something in the meantime, I do not remember it is possible to > change axses acceleration on Lcnc, but only speed. I think in the new > versions 2.8 there should be a "pin selector in hal file" to use a > ramp of acceleration rather than another, but here too they should > also make this strange memory clear to me .... but that you can vary > the acceleration with an MPG it sounds to me very strange. Speed > instead ..... sounds better. > > bkt > In the dials I added for independent x-z control, no attempt was made to control the accel's used, in fact without some further hal trickery I don't know if its possible. So each movement is fed into the jog input as a motion times selected scale unit, eg 1 click can be up to .2" in my original configuration, but that was way too easy to "wind up", leaving the axis moving at maximum speed some unknown distance with the potential for crashing into things, so I have now restricted it to 50 thou per click, still enough to encounter the wind up, catch up scenario. 20 thou as a maximum jog increment may wind up being my choice. Minimum is .0001" which will get there but is slow. Very handy for dialing in that last 3 thou to size. The jog inputs to motion do not have a velocity pin, but this is an instance where one might find it usable if it was available.
As is, once it exceeds the step size of the motors full step, its also obviously noisy. Z in particular as the keyboard & mouse table is on top of the z motor mount, which was designed to use the same 3 bolt holes in the bed that formerly held the QCGB driving the screw. Vibration coupling is excellent. :) That motor is serious overkill at 1600 oz/in, but its what I had left after I took it off the G0704, and moves Z on the lathe 3x faster than it could on the G0704, and its geared down 30 teeth to 42 on the 5 tpi screw. So where it was stalling at 30"/min on the G0704, it can move at nearly 150 ipm if the accels are gentle enough. But its steps are so violent (I should play with the drivers current, it doesn't need the brute force of a 1600 there) I'm going to have to scrounge up a bigger piece of 3/4" and put a skirt around the front and ends to keep the mouse from vibrating off while its running a long program. And a splash guard on the rear to keep flying oil from the rear spindle bearing from spraying all over the keyboard by raising a barrier up and over the bearing. > 2017-08-30 18:16 GMT+02:00 王若溪 <[email protected]>: > > I have an XHC-HB04 18-button wireless MPG on my mill. It's amazing > > that it works on LinuxCNC. But I found something confusing about > > acceleration: > > > > 1. The acceleration in [XHC_HB04_CONFIG]mpg_accels seems to have > > an effect on both jogging and program running. Isn't it supposed to > > affect MPG > > jogging only? > > 2. Probably not related to XHC_HB04. Jog acceleration when using > > Shift+Arrow keys seems to be higher than G0 acceleration. I > > thought they should be identical. I'm using Axis GUI, > > [AXIS_#]MAX_ACCELERATION = 250, [AXIS_#]STEPGEN_MAXACCEL = 937.5 mm's obviously. > > Maybe there is some internal mechanism that I don't know, hope > > someone could cast some light on it. Thats my light, batteries could be weak though. :) Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
