Re: Gearhead motors ? future drives ?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "washcomp" <jeff@w...> wrote:

> Um Dave,
>
> MACH3 is currently able to interface to a PLC through Modbus (spoke
> to a guy today who's using it on his Bridgeport connecting Modbus out
> his RS-232 port). Gives loads of I/O and analog inputs. Gecko will
> support USB for enhanced I/O (but less than PLC) and biggest
> advantage is enhanced pulsing.
>
> At least that's my understanding as of today.
>
> Jeff

The modbus allows simple I/O and could output more data, but as far as
I know, no one has something that will send out a serial command so
that the machine will move 3 axes with each having ramp and speed
independantly but in unison.

I know it's comming, but there is no driving need to force the issue.

All the timing of step and direction has to be moved from the PC to
the micro controller on the controller/driver card.

But, that was not the point I was trying to make.

The step will be an evolution to another platform. It will not bring
any single task that cannot be done now, nor assortment of tasks that
cannot be done now.

It will offer much faster and smoother pulse streams for faster and
smoother motor operation.

But, without the new stepper driver from Gecko that also will monitor
stepper locaton via and encoder, running a stepper at those rates is
not valuable.

Todays limit is 45,000 hz, and with a 10x driver, that means 4,500hz
full steps for a stepper, 4,500 / 200 = 22.5 rev's a second, times 60
= 1,350 RPM

Granted that some people might want more than 1,350 RPM on a stepper,
but in that range, power is fading.

AND, there is technology today that can deliver power and speed and
does not require new software.

Maybe I'm missing why this new method is important, or what feature(s)
is being added that will enhance our machines.

It seems to me that when you peal back the curtain, the bottom line is
that we are using one microprocessor to display information on teh
Windoz platform, and a second to perform the actual controller
functions on a second (FASTER) platform.

That the goal is to get away from the Intel microprocessor and it't
inherent slowness for this sort of work.

So... maybe a PLC can be used to be that interface ? much simplier
microprocessor with much less overhead, exisiting platform, existing
hardware and software and even I/O modules.

Well, that was long winded...

The point is that if you have a machine you want to upgrade, or a
machine you want to build, the mechanical bits and bobs will be the same.

the main PC will be the same,

The motors will be the same,

the wireing will be the same,

that waiting for some new technology does not make sense when there is
no tangable benifit AND when said technology does become common,
stable and de-bugged, one can always upgrade.

Dave