RE: [CAD_CAM_EDM_DRO] Dead zone in stepper power curve

I think on the Gecko white paper this is referred to as mid band
instability. I know that Gecko uses feedback from the motor to actively
modify the output and stabilize the motor.

Tim
[Denver, CO]

> -----Original Message-----
> I was wondering if anybody had encountered this problem. I'm
> developing my own stepper controller system and experience the
> following...
>
> when I run a smooth speed ramp, there are certain speeds at which
> the motor doesn't like to run. Not fast speeds, but slow ones. I'm
> running assembly on a microcontroller, and the pulses are very
> accurately timed.
>
> Depending on how I set the winding power (it's a chopper drive), I
> can tune out these dead spots. Usually by decreasing the power.
>
> Do you think this is a resonnance problem? Or is it more likely to
> be a problem with my code?
>
> I've scoped the waveforms and they are uniform and glitch free
> through the problem speed zone.
>
> Any thoughts?
>
> Thanks,
> Ted
>
>
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