CAD CAM EDM DRO - Yahoo Group Archive

RE: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent

Posted by dlantz@a...
on 2002-02-14 11:02:45 UTC
SO WHAT im hearing here is that for 'jog wheel'-s we need a shorted cheapo
stepper with the donut shaped encoder on the shaft, with a knob on it, with
the encoder connected to a chip to create step and direction pulses... um...
but how would that chip know what DIRECTION you are going in? do encoders
provide this information somehow?---dave l.

-----Original Message-----
From: mariss92705@... [mailto:mariss92705@...]
Sent: Thursday, February 14, 2002 10:33 AM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent


Hi,

I don't mean to pour cold water on the idea of using a step motor as
an encoder but I don't think it will work.

At speeds above 0.5 revs/sec it's a piece of cake. The winding
voltages are sine/cosine. A pair of simple zero-crossing comparators
give a clean quadrature output.

The rub, and where it all falls apart, is at speeds below that.

I did some quick experiments. Where detent torque can be felt, moving
the motor in single detent increments produces narrow 50 mV, near
simultaneous pulses on both channels. It would require
differentiation of the pulses to retrieve phase timing info from them
which then could be "assembled" into a quadrature output.

When a "real world" inertial and frictional load is coupled to the
motor (a 4" dia, .125" aluminum disk and 10 oz-in friction), it
washes out the detent and the voltage outputs fall below 2 mV.

This signal is below the "noise" level. The motor is microphonic;
simply tapping a pencil on the bench next to it produces 10 mV of
signal.

The result would be an encoder that has no output if the handwheel
were turned at a rate less than 0.25 revs/sec. Above that speed the
quadrature output would suddenly start running at 50 counts per
second. That would be very irritating.

Mariss

--- In CAD_CAM_EDM_DRO@y..., Scot Rogers <scotr@b...> wrote:
>
> Hey all,
>
> I think someone could be on to something with using a stepper for a
> jogwheel. I'm currently waiting on a lathe with just such a
device, and the
> wheel is great.
>
> One thing though. Wouldnt it be best, since the graduations of
jogs are in
> decimal, to use a 3.6 degree stepper instead of a standard 1.8
degree? It
> would make exactly 100 marks and big, well defined dentents at
that. If the
> pulses could be generated with the motor, there could be a way to
hack the
> mouse if the device were used in a program like EMC.
>
> Scot
>
>
>
> /?*$#@%!&*
> -------------------------------------------
> Give me open source, or give me open sores!
> -------------------------------------------


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Discussion Thread

Doug Fortune 2002-02-13 21:17:30 UTC rotary hand encoder wheels with detent Brian Pitt 2002-02-13 21:37:28 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-13 21:56:23 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent ballendo 2002-02-14 04:03:40 UTC Re: rotary hand encoder wheels with detent dlantz@a... 2002-02-14 05:40:26 UTC RE: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Brumley 2002-02-14 06:08:27 UTC Stepper Motor Source Garry & Maxine Foster 2002-02-14 06:39:20 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Mr. sausage 2002-02-14 07:18:21 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Doug Fortune 2002-02-14 07:55:23 UTC RE: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent rcstickman 2002-02-14 07:57:12 UTC Re: Stepper Motor Source Doug Fortune 2002-02-14 08:00:32 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Scot Rogers 2002-02-14 08:26:26 UTC RE: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent dlantz@a... 2002-02-14 09:16:20 UTC RE: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Mark Ehle 2002-02-14 09:28:36 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source Jon Elson 2002-02-14 10:16:57 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source mariss92705 2002-02-14 10:33:13 UTC Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 10:44:36 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent dlantz@a... 2002-02-14 11:02:45 UTC RE: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Ian W. Wright 2002-02-14 11:27:34 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 11:57:14 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 12:11:20 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source dlantz@a... 2002-02-14 12:15:56 UTC RE: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 12:23:39 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 12:26:41 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-14 12:54:17 UTC Re: [CAD_CAM_EDM_DRO] rotary hand encoder wheels with detent Carol & Jerry Jankura 2002-02-14 13:52:00 UTC RE: [CAD_CAM_EDM_DRO] Stepper Motor Source flyspeck1@a... 2002-02-14 16:07:12 UTC Re: rotary hand encoder wheels with detent JanRwl@A... 2002-02-14 18:46:36 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source Doug Fortune 2002-02-14 19:19:13 UTC Re: rotary hand encoder wheels with detent Mr. sausage 2002-02-14 21:03:49 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source Jon Elson 2002-02-14 22:35:02 UTC Re: [CAD_CAM_EDM_DRO] Stepper Motor Source Ian W. Wright 2002-02-15 02:59:37 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent aspaguy 2002-02-15 12:51:26 UTC Re: Stepper Motor Source tedinoue 2002-02-16 03:55:19 UTC Re: rotary hand encoder wheels with detent imserv1 2002-02-16 09:00:47 UTC Re: rotary hand encoder wheels with detent audiomaker2000 2002-02-16 09:13:19 UTC Re: rotary hand encoder wheels with detent audiomaker2000 2002-02-16 09:29:09 UTC Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-16 14:22:05 UTC Re: rotary hand encoder wheels with detent wanliker@a... 2002-02-16 17:18:28 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent imserv1 2002-02-16 22:20:11 UTC Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-17 12:10:29 UTC Re: rotary hand encoder wheels with detent audiomaker2000 2002-02-17 12:30:53 UTC Re: rotary hand encoder wheels with detent imserv1 2002-02-17 13:42:18 UTC Re: rotary hand encoder wheels with detent wanliker@a... 2002-02-17 15:20:14 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent ballendo 2002-02-17 23:20:53 UTC ball plungers was Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-18 10:35:51 UTC Re: rotary hand encoder wheels with detent Mike Snodgrass 2002-02-18 11:19:07 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-18 11:20:26 UTC Re: rotary hand encoder wheels with detent Alan Brumley 2002-02-18 11:37:08 UTC RE: [CAD_CAM_EDM_DRO] Stepper Motor Source Alan Marconett KM6VV 2002-02-18 11:45:39 UTC Re: rotary hand encoder wheels with detent Carlos Guillermo 2002-02-18 11:51:34 UTC Re: rotary hand encoder wheels with detent Angelos 2002-02-18 12:27:17 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Brian Pitt 2002-02-18 13:03:35 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Smoke 2002-02-18 14:05:15 UTC Re: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-18 14:10:09 UTC Re: rotary hand encoder wheels with detent imserv1 2002-02-18 14:34:16 UTC Re: rotary hand encoder wheels with detent Carol & Jerry Jankura 2002-02-18 17:46:01 UTC RE: [CAD_CAM_EDM_DRO] Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-18 17:46:55 UTC Re: rotary hand encoder wheels with detent ballendo 2002-02-19 02:08:27 UTC Feedrate overide was Re: rotary hand encoder wheels with detent ballendo 2002-02-19 04:05:06 UTC keyboard typematic and old dos stuff was Re: rotary hand encoder wheels... Alan Marconett KM6VV 2002-02-19 10:54:07 UTC Re: rotary hand encoder wheels with detent jeffdavis516 2002-02-19 11:23:47 UTC Feedrate overide was Re: rotary hand encoder wheels with detent Alan Marconett KM6VV 2002-02-19 11:31:56 UTC Re: [CAD_CAM_EDM_DRO] Feedrate overide was Re: rotary hand encoder wheels with detent