On Wednesday 24 November 2021 04:54:02 John Dammeyer wrote: > Hi Gene, > This doesn't answer my question. . > > How does one tell the spindle to do one revolution at 0.5 rps and stop > either after one rev or when a sensor input is detected? Given that > I'm running the MESA board in step/dir mode.
I would use the pulse you have as a both time reference and as a counter in the hal file, Start the counter at zero, until the count is one, and if thats not long enough, put in a oneshot to stretch it, or wait to stop at a count of 2. Running a stepper, the sudden stop might cause a step skip but at that slow a speed I doubt it. Use the end of the oneshot to rezero the counter for the next tool change. Lowering the socket could be done gently, very low air pessure, while turning the spindle slowly until the socket drops onto the nut, reverseing the spindle for a few milliseconds to give it enough slack to fall all the way. then drive the stepper, turning everything until the lock pin drops in. tally that so you can start the unlock 2 turns. For locking, drive it the other way but use a oneshot to time it so the stepper cogs once and gets shut down. Rough outline, I've probably forgotten something. > Thanks > John > > > -----Original Message----- > > From: Gene Heskett [mailto:ghesk...@shentel.net] > > Sent: November-23-21 7:44 PM > > To: emc-users@lists.sourceforge.net > > Subject: Re: [Emc-users] Spindle positioning. > > > > On Tuesday 23 November 2021 21:33:21 John Dammeyer wrote: > > > Still wondering how I might make the spindle turn slowly and then > > > stop on a sensor signal. From the HAL file it's set up the same > > > way as the XYZA axis with respect to step_type and control-type. > > > > > > I'd want to set the velocity to say 30 RPM (0.5 RPS) and during a > > > revolution if it detects an input the motor is stopped. > > > > > > # SPINDLE Step Gen signals/setup > > > setp hm2_7i92.0.stepgen.05.dirsetup [SPINDLE_9]DIRSETUP > > > setp hm2_7i92.0.stepgen.05.dirhold [SPINDLE_9]DIRHOLD > > > setp hm2_7i92.0.stepgen.05.steplen [SPINDLE_9]STEPLEN > > > setp hm2_7i92.0.stepgen.05.stepspace [SPINDLE_9]STEPSPACE > > > setp hm2_7i92.0.stepgen.05.position-scale [SPINDLE_9]STEP_SCALE > > > setp hm2_7i92.0.stepgen.05.step_type 0 > > > setp hm2_7i92.0.stepgen.05.control-type 1 > > > setp hm2_7i92.0.stepgen.05.maxaccel > > > [SPINDLE_9]MAX_ACCELERATION setp hm2_7i92.0.stepgen.05.maxvel > > > [SPINDLE_9]MAX_VELOCITY > > > > > > net spindle-enable => hm2_7i92.0.stepgen.05.enable > > > net spindle-vel-cmd-rps => hm2_7i92.0.stepgen.05.velocity-cmd > > > > For that sort of accuracy, put high rez a/b encoder on the motor > > armature, but get the index from a hall effect watching the socket. > > That will pretty much do away with quantization noise and will let > > you set the stopped point to a small fraction of a degree. > > > > Or use that stepper with at least a 10x geardown if it has enough > > twisting power. Or a stepper with a 90 degree worm drive. I have > > one of the small ones with a 5/1 worm that might be able to do my > > g0704 with a 3NM nema23 on it. But they make that one at much higher > > ratios than this 5/1. There's also good looking plantary inline > > reducers for nearly the same money that look stronger than a worm > > drive. > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > 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, 1940) > > If we desire respect for the law, we must first make the law > > respectable. - Louis D. Brandeis > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > _______________________________________________ > > 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 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, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
