CAD CAM EDM DRO - Yahoo Group Archive

Re: stepper vs servo

on 2001-08-08 01:41:39 UTC
Jon Elson <elson@p...> wrote:
> Servos don't stall, unless the physical limits of the machine are
reached.

Trying to get exact meaning of terms:
stall = stop?
stall = stop temporily?
Servos don't stall = there are no conditions, however severe, that
they will stop/stop temporily when they are supposed to be moving?
When torque is insufficient, only the feedrate fall below the
commanded feedrate?

For steppers:
stall = stop?
stall = lose step?

> They can slow down, however. Some systems (the Allen-bradley 7320
> I worked with before, for instance) had a feature called feed-rate
> compensation.
> Whenever one axis lagged more than some limit behind commanded
position,
> all axes cut their feedrate in half, hoping that would allow the
lagging
> axis
> to catch up.

Meaning servos alway act in unison? When Y slow down, X will slow
down simultaneously, and there is no time-lag?

My feeble mind: The only way that X will know Y has slowed down is
when Y has already slowed down and a signal is issued that this has
happened, by which time X may already have proceeded some steps
beyond Y? By which time there will already be some deviation, even if
minute, from the planned path? Is the answer below:

> And, it is most likely that the lagging axis will leave extra
material in
> place,
> rather than remove extra material, and a later pass can clean it up.

Thanks in advance

Peter

Discussion Thread

cadcamcenter@y... 2001-08-07 17:17:24 UTC stepper vs servo cadcamcenter@y... 2001-08-07 17:22:54 UTC Re: stepper vs servo JanRwl@A... 2001-08-07 17:28:53 UTC Re: [CAD_CAM_EDM_DRO] stepper vs servo Stephen Goldsmith 2001-08-07 17:40:07 UTC Re: [CAD_CAM_EDM_DRO] stepper vs servo Jon Elson 2001-08-07 23:27:10 UTC Re: [CAD_CAM_EDM_DRO] stepper vs servo cadcamcenter@y... 2001-08-08 01:41:39 UTC Re: stepper vs servo Carol & Jerry Jankura 2001-08-08 05:29:24 UTC RE: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-08 10:12:01 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo brian 2001-08-08 11:31:46 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo cadcamcenter@y... 2001-08-08 14:40:16 UTC Re: stepper vs servo JanRwl@A... 2001-08-08 17:05:31 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo mariss92705@y... 2001-08-08 17:55:44 UTC Re: stepper vs servo Jon Elson 2001-08-08 22:31:10 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo info.host@b... 2001-08-08 23:40:50 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo cadcamcenter@y... 2001-08-09 01:35:56 UTC Re: stepper vs servo Ian Wright 2001-08-09 03:25:59 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo cadcamcenter@y... 2001-08-09 05:02:16 UTC Re: stepper vs servo cadcamcenter@y... 2001-08-09 05:03:05 UTC Re: stepper vs servo cncdxf@a... 2001-08-09 05:49:39 UTC Re: stepper vs servo Chicken & Egg Art Fenerty 2001-08-09 09:01:31 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Chicken & Egg Tim 2001-08-09 09:22:04 UTC RE: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 10:54:04 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 10:59:33 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 11:12:13 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 11:19:17 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo jguenther@v... 2001-08-09 11:22:02 UTC RE: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 11:27:44 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Chicken & Egg Alan Marconett KM6VV 2001-08-09 12:06:16 UTC Re: stepper vs servo cncdxf@a... 2001-08-09 12:14:46 UTC Re: stepper vs servo Chicken & Egg Weyland 2001-08-09 12:19:53 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Alan Marconett KM6VV 2001-08-09 12:45:35 UTC Re: stepper vs servo Weyland 2001-08-09 13:04:05 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo JanRwl@A... 2001-08-09 15:05:59 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 21:12:57 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jon Elson 2001-08-09 21:19:12 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Chicken & Egg Jon Elson 2001-08-09 21:50:55 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo M. SHABBIR MOGHUL 2001-08-15 00:28:19 UTC hi all smeboss 2003-03-11 17:42:06 UTC stepper vs servo smeboss 2003-03-11 17:42:06 UTC stepper vs servo Lloyd Leung 2003-03-11 17:54:57 UTC RE: stepper vs servo kdoney_63021 2003-03-11 18:57:34 UTC Re: stepper vs servo smeboss 2003-03-11 19:43:04 UTC Re: stepper vs servo JanRwl@A... 2003-03-11 22:37:23 UTC Re: [CAD_CAM_EDM_DRO] stepper vs servo kdoney_63021 2003-03-13 05:53:42 UTC Re: stepper vs servo smeboss 2003-03-13 07:01:12 UTC Re: stepper vs servo ddgman2001 2003-03-13 10:04:19 UTC Re: stepper vs servo dakota8833 2003-03-13 13:09:35 UTC Re: stepper vs servo Jon Elson 2003-03-13 22:06:45 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo ddgman2001 2003-03-15 14:18:59 UTC Re: stepper vs servo Jon Elson 2003-03-15 22:23:50 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo ddgman2001 2003-03-17 08:56:33 UTC Re: stepper vs servo Jon Elson 2003-03-17 09:34:25 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Monte Westlund 2003-03-23 16:24:56 UTC Re: stepper vs servo Jon Elson 2003-03-23 17:22:08 UTC Re: [CAD_CAM_EDM_DRO] Re: stepper vs servo Jeff Goldberg 2003-03-23 18:31:48 UTC RE: [CAD_CAM_EDM_DRO] Re: stepper vs servo J Hamilton 2003-03-23 18:54:29 UTC Re: stepper vs servo