RE: Angular axes

["John Guenther" <j.guenther-at-verizon.net>]

Hi Chris.

I have determined this evening that it does not seem to make any difference
whether the axis is configured as LINEAR or ANGULAR it just plain does not
work at any reasonable speed with the INPUT_SCALE and OUTPUT_SCALE set to
any thing less than 1000 steps per unit.  It also appears to totally ignore
the UNITS parameter on the fourth axis.  You are correct in that if the
fourth axis is configured identically to the other axis it will work at
reasonable speeds but you cannot tell it to move say 90 degrees other than
by decimal numbers such as g0 a0.25 will get you a 1/4 revolution move.
This is not how I want to use my rotary table.  Oh well, I am sure it will
get fixed sooner or later.  Maybe I will have to brush up on my C skills and
fix it may self, which is NOT what I want to do.  I want to build engines,
not fix software.

John Guenther
Sterling, Virginia

> -----Original Message-----
> From: emc-at-nist.gov [emc-at-nist.gov]On Behalf Of Chris Wagner
> Sent: Wednesday, July 03, 2002 11:29
> To: Multiple recipients of list
> Subject: Angular axes
>
>
>
> Greetings,
>
> There has been list traffic about various problems with angular axes,
> so I thought I would try some tests.  I will eventually (very long term)
> want to use a rotary table.
>
> I found a problem similar to J Guenther - very slow motion.  I played
> around with my .ini and found that the problem occurs anytime there is
> an angular axis (any of X R, X Y R, X Y Z R, X Y Z R P W).  The slow
> motion also effects the linear axes - they also creep along.  I would
> expect that adding a fourth axis would not effect the behavior of the
> previous three, but it does.
>
> As far as .ini understanding or parsing issues go, I did get a setup
> that would run all the axes fast, by simply copying my three existing
> linear axes sections (the [AXIS_0] etc) to three new sections, changed
> the new [AXIS_x] tags to sequential numbers, used AXES=6, COORDINATES=X
> Y Z R P W in the [TASK] section.  I did _not_ set the three new axis
> type to angular (or make other changes).  The front ends (Tkemc, yemc)
> then show all 6 axes (XYZRPW), and all axes will clock at high speed.
> Moves work with e.g., G1X10Y20Z30A20B30C50 ...  (also works with XYZR)
>
> Of course It would be hard to set steps/revolution or degree since the
> axis section is setup for linear units...
>
> Tentative conclusions:
> 1) Problem is in setup/understanding of ANGULAR .ini configuration.
>
> 2) Something is wrong with the emc parsing of the ANGULAR ini.
>
> --
> Recreational Calculus - Just For Fun!
>
> Chris Wagner
> clwagner-at-eecs.wsu.edu
>
>
>