Re: [CAD_CAM_EDM_DRO] Clarification for microstepping requirement

The biggest benefit of microstepping in my view is that is greatly
reduces the resonances caused by steppers in full-step mode. This
resonance is sometimes enough to lose useful torque at certain step
frequencies, in addition to the other undesirable effects of vibration
on the machine it is attached to. Microstepping shouldn't be relied on
for greater accuracy, but it it worth it for reducing resonance and
getting more even torque response from the motor.

Richard

On Mon, 2005-12-12 at 21:20, ERIC QUARNSTROM wrote:
> Hey all:
>
> I read the great FAQ's on this site regarding steppers and how they work and
> microstepping. Very inciteful and I think I even understand how they do it.
> What I can't quite figure out is why it is required. In one of the FAQ's it
> says the primary purpose for microstepping is to eliminate the jerkyness
> between steps. However, when I do the math on my proposed set up I come up
> with a movement of the axis per step that is so small I can't consider it to
> be 'jerky'. Therefore I am afraid I either didn't understand what I read
> well enough or I'm missing something. My math is below and I welcome
> comments.
>
> System statistics:
> Lead screw with 10 TPI
> 1:2 gearing between motor and lead screw
> motor with 200 steps/revolution
>
> My math:
> Every turn of the lead screw gear produces .1 inches of travel.
> Every turn of the motor gear produces .05 inches of travel
> Motor has 200 steps per turn of the motor so every one step would produce
> .05/200 inches of travel
>
> In summary .00025 inches of travel per full step seems like a very small
> amount of movement. So why would I need to divide that by 10 for a
> microstepping drive?
>
> Thanks in advance,
> Eric Q.
>
>
>
>
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