Chris Radek <[EMAIL PROTECTED]> wrote:
> On Mon, Oct 08, 2007 at 07:51:59PM -0600, Sebastian Kuzminsky wrote:
> >     reference voltage: 19.1 V DC
> >     no-load current: 0.16 A
> >     Peak/Stall Current: 2.51 A
> 
> I think these are the same motors I'm using on my sherline lathe.

Mine is an 8322, yours is a 9413, I can read the label in this picture:
<http://timeguy.com/cradek-files/cnc/lathe/DSCN6295.JPG>

The current lineup of 9xxx motors have much more torque than the
8xxx series motor I'm using, but I think the 9x14 winding has been
discontinued, I can't find the specs on it.

How many lines do your encoders have?

Where did you get the belts & wheels for the X & Z axes on your lathe
CNC conversion?  What's the transmission ratio?

What kind of leadscrews are you using?


> > Duty cycles from 0 to about 55% give me increasing whining from the
> > motor but no movement at all.  55 to 100% gives increasing motor speed
> > and torque.
> 
> I think my linearity is much better than you describe.  Maybe try
> pure pwm mode (not pdm)?  Or it may just be a matter of your low
> power supply.  I'm using 24V on mine.

I really need to scrounge up a better power supply...

I'll try PWM too.

Can I see your HAL config?


> pwm/pdm also have scale and offset parameters that might help you.

I thought of using pwmgen.scale, but isn't that equivalent to just
increasing the PID gains?

Hm, there's also pwmgen.min-dc, which you can set and it gets added to
the duty cycle.  That'd probably work, but at the cost of always running
at that min-dc value.  It'd be pretty similar to the HAL circuit I hacked
up a few nights ago, which would add an offset to dc's greater than 0.01,
so that it would settle down when it reached the target.


Thanks for all the suggestions!


-- 
Sebastian Kuzminsky

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >> http://get.splunk.com/
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to