Re: [CAD_CAM_EDM_DRO] re:Re: mill threading, Acceleration, Axis

ballendo@... wrote:

> Alan,
>
> Jon already gave you some good advice. I'll add in a different
> direction...
>
> The "best" acceleration "curve" for a stepper motor is generally
> considered to be the "S" curve. This is where we start acceleration
> slowly, then accelerate the acceleration (yep, read that one twice!),
> and then do the reverse to slowly move into the desired step rate.
>
> It's two exponential curves back-to-back. The benefit here is that
> the acceleration RATE is low at the beginning and end of
> the "ramp"(curve), where the inertia of the load is against us. And
> the acceleration RATE is HIGH in the "middle" of the ramp, so we get
> to our desired rate as quickly as possible.

Do you gain anything by tableizing the sigmoid curve in normalized form and just scaling it....or are the processors today so fast
they are not challanged?

Dave