Re: [CAD_CAM_EDM_DRO] Servo control from PC

> Has anyone had any luck running a servo system directly from a pc? I
> have used numerous PCI cards and they work great, but are expensive.
> I was wondering if an interface exists for driving the amplifier
> inputs and receiving encoder inputs from parallel ports. Is Visual
> Basic or some form of C programming capable of this? I have used
> Visual Basic as an interface for the PCI motion control cards.
> I know Geko makes drives capable of running servo motors using step &
> direction signals from stepper software. Has anyone done this and is
> the performance truely that of a servo system? I'm not looking for
> top servo performance, but I would like better than stepper can
> provide.
> Thanks
>

If what you are asking is can you hook up your analog servo amps to the
parallel port and work some magic with VB or C to run them , the answer is
no. Standard servo amps have an analog input of + or - 10V and the parallel
port is strictly digital

I as well as others on the list use step and direction servos driven by
Geckos and Rutex drives and while I can't speak for the Rutex drives, the
performance of the Gecko servo drives is very good. Much much better than
steppers in my opinion. I will never use steppers again after using servos.
I was never 100% confident that my stepper system was where it was supposed
to be. Every time I ran my machine I was always wondering if I just ruined
that piece of aluminum because of lost steps. I know others have got their
steppers to work well but I never could. Since I got the Gecko servo drives
I no longer worry about such things.

John Elson has an interface that hooks to the parallel port and drives
standard analog servo drives, although as far as I know it is only supported
by EMC.

Bill