Re: [CAD_CAM_EDM_DRO] Re: tach output

"Jon Elson" <elson@...> wrote:

>
> Well, I have a strong preference for real servos. The difference with the
> Gecko drives is that the CPU has no position feedback. It sends step
> pulses to the Gecko, and hopes it got there.

Is it possible to use a linear encoder of some sort to provide the feedback
to the Gecko driver in place of a rotary encoder on the servo motor shaft? I
realise that this would still not provide position feedback to the CPU but
it might provide some compensation for backlash in the lead screw.

Regards,

Dave.

David Micklethwaite

> If you have a crash,
> axis fault, emergency stop or whatever, you have to re-home the system
> so the CPU knows where the machine is. You can't use the CNC program
> as a DRO and move the machine manually. Also, at extremely slow speeds,
> the gecko drives move in a step-step fashion. I can get smooth motion
> down to about .01 IPM with my tach-servo system.
>
> Servo amps are available on eBay, sometimes for quite reasonable prices.
> In this case, it sounds like you only need one.
>
> Jon