Re: Why is the push to such high step rates (Grex and Arc100)?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "lcdpublishing"
<lcdpublishing@...> wrote:

>
> That's what I am trying to grasp, what applications are there that
> utilize such high speed & high resolution?
>
> Based on the little that I know about drives, motors, and
> electronics, the only thing that I can see with a 256 microstep
> drive is just to have a larger number of steps within a given about
> of rotational displacement. It has been said by many that you
> cannot rely on the precision of the microsteps, only the full steps
> of a stepper motor. So, if that is correct, then the only advantage
> of having 256 microsteps is perhaps a smother motion? Again,
> assuming microstep as a stepper motor driver, how many stepper
> motors are out there that can deliver any useable torque over 1000
> RPM?
>
> As for servos, I can see where you can put on them very high
> resolution encoders, but where and how would you use something like
> that? Servos don't have much in the form of low RPM torque, so
> running something direct drive with them is unusual such as a timing
> belt pulley attached directly to the servo.
>
> As for resolution and precision, in machine tools, it's pretty hard
> to find anything with a resolution better than .0001" or .001MM.
> Beyond that is very impractical without taking some very special
> steps to insure the mechanicals can deal with any more resolution.
>
> Perhaps there is something in the production of silicon wafers or
> something that this sort of resolution and speed is utilized? I
> can't imagine anything in: metal working, woodworking, robotics,
> etc. so I am sort of stumped as to what applications this would be
> for?
>
> Thanks
>
> Chris
>
>
>
>

Chris you need to realize that you are dealing with hardware engineers
(emphases on Engineer). I are one so I can talk about them! If the
latest greatest chip can do those numbers then SOMEBODY must need it!
Often times it's a solution looking for a problem.

Forgive me if I don't get real excited about the "do everything"
products (all they lack is just a "little" programming). I work down
in the trenches with the guys building their own machines (and a few
OEM's). I still have to answer the most basic of questions. Most of
my support on my hardware is not the hardware itself but things like
MACH3 setup, toolpath development, How to do things like turn on the
spindle or setup Home switches (;-)


Tom Caudle
www.CandCNC.com