On Monday 02 November 2015 10:28:13 andy pugh wrote: > On 2 November 2015 at 15:08, Gene Heskett <[email protected]> wrote: > >> Also, that example includes spindle orient. You might want to > >> consider a spindle orient commands rather than a spindle start > >> command. > > > > I've no clue how a velocity servo could do that neatly because of > > the inevitable variations in bearing friction. > > PID.
Already in there, setup for velocity. That, its quite stiff at doing. [SPINDLE_9] P = 2.0 I = 0.03 D = 0.00 FF0 = 1.00 FF1 = 0.020 FF2 = 0.00 BIAS = 0.00 FBIAS = 0.60 RBIAS = -0.60 ACCELL = 6.7 LIMIT_S_ACCEL = 750 DEADBAND = 0.00 ENCODER_SCALE = 268.0 PWMGEN_S_SCALE =46.00 MAXACCEL = 1500 PWMGEN_S_FREQ = 30000 NEAR_TOL = 5 NEAR_SCALE = 1.1 ENCODER_SAMPLE = 500000 Suggested changes to make position work? The accuracy, at that encoder scale is no better than a couple degrees. It would have to interpolate, and hunt, or use a deadband to stop the hunting. My thinking has been one of working around that limit since I do not intend to ever drop the 3/4" R8 as long as I have TTS adapters left, unless I have to disable the tool changer and do a special setup by hand. Working around that limit also gives turning room so there is some inertial energy in the spindle when the drawbar wrench hits its stop pin. That should help to loosen or tighten the drawbar. Playing with the code, using that 4" as a limit, I can put 6 pockets in it, and won't have to make the shaft clamp cap, there's room for the hole and a setscrew or 2 to fix it to the 1/2" shaft. Got that worked out, and about to be started on the toy mill. News at 11. Thanks Andy. 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
