Re: [CAD_CAM_EDM_DRO] Re: G320 Position Error Fault

R Rogers wrote:

> Jon,
>
> Oh sure I understand that. The encoder board I sell tracks the encoder at the control software as well. Although, it ONLY tracks position and Estops if a count error. Any Mach3 system that does a sudden stop presently will lose position. I guess thats how I shouldve said that. I meant any system running Mach3 regardless of motor type or size.
>
> With EMC you can be flat out at high rapid, terminate the script and position is not lost, commanded to actual machine position?

Yes, that's right. As long as you have an encoder on the motor,
and a way to read that in to the PC, you have continuous
monitoring (and graphing, any time you want to check it out)
at the servo update rate. Nominally, that is at 1 KHz.

One of the neat things you can do with this is have a sliding
scale following error limit. So, the error bound can be very
tight at standstill and much looser at high speed. You also
have the ability to add feedforward terms to the PID
calculation, which can reduce following error to the
infinitesimal over a wide range of speeds. I have a minimill
tricked out with servos, and I have gotten the following error
down to 200 uInches up to 50 IPM. This is ridiculous, of
course, on such an imprecise machine, but the servos are
tracking commanded position with amazing accuracy.

Jon