Re: Two Q's: Servo Hum and FreqMod issues

Jake,

You are not alone. I see the same thing when using freqmod. However
for some reason, if I set the INPUT_SCALE and OUTPUT_SCALE higher (say
8000.0) the problem goes away. wierd...

Norm

--- In CAD_CAM_EDM_DRO@y..., "mariss92705" <mariss92705@y...> wrote:
> Try turning the GAIN trimpot down a smidge and see if the "rumbling"
> quiets; you may have it up too high.
>
> Mariss
>
> --- In CAD_CAM_EDM_DRO@y..., "jbordens" <jake@a...> wrote:
> > Got to questions for you wise folks here in CCED...
> >
> > #1 - I've got my servos working well on the bench. My maximum
> > velocity is set to .60 ips, which should be within the range of my
> > servo motors. When I jog, say by running a "G0 X10", the motors
> > accelerate on a nice conversevative acceleration profile. When
> they
> > reach their max velocity they start to ruble/hum.
> >
> > So Q#1: is this normal?
> >
> > I assume this is normal because the servo drive is doing is
> feedback
> > loop thing, and breaking the motor to prevent it from going too
> > fast. Even though I've already tuned my motors using the gecko
> > osciloscope method, I want to be sure that this isn't a symptom of
> > being out of 'calibration'.
> >
> > #2 - I'm using steppermod right now, and all works perfect. When
I
> > switch to FreqMod with a period of .000025 (150mhz pc) and
> > STEPPING_TYPE=0 (drn, step), funny things happen. When I run a
> > command like "g0 x5", the motor seeks to about where 5" would be,
> > but then the motor reverses and slowly seeks backwards and doesn't
> > stop.
> >
> > So Q#2 - any ideas why freqmod is behaving badly.
> >
> > Thanks to all. Have a great weekend.
> > Jake