re:Re: mill threading, Acceleration, Axis

Mariss,

I love when you point out these "overlooked" or "misunderstood/
misinterpreted" things! There is a BIG difference between the real
world implementation and the theory. I'm glad I'm not alone here :-)

Ballendo

P.S. Just came back from consulting on a Hi- dollar project. A lot
changes when you can throw a LOT of money at the problems. The
answers are indeed different; when the same questions are asked!

>My experience has been that the touted advantages of these profiles
>over a linear ramp aren't as great as one would hope. The major
>detractor is the inevitable "staircasing" that results from software
>generated acceleration ramps. Each is an infinite impulse and will
>pump the motor resonance.

<snip>The results were the staircase frequency had to be above 3kHz

>to accrue real benefit. This was beyond the capability of the CPU I
>was using by an order of magnitude.
>Mariss