Re: [CAD_CAM_EDM_DRO] Re: Open (i think) design for a parallel robot (reprap may be interested)

Dennis Schmitz wrote:

> Not really. Since CAD models are built in a cartesian coordinate system,
> somewhere along the way you need to translate into a motor space. Whenever
> you translate co-ordinate systems, you get quantization error at the encoder
> (or step) resolution.

In the cartesian axis case, I don't think quantization error is a given,
because the step resolution can match the coordinate system resolution.
In my case, for example, steppers are 200 steps/rev, and leadscrews
are 10TPI. That gives a quantization of 0.0005".

So, as long as I specify coordinates in 0.001" increments (which is what
I normally do), there's an exact representation in motor coordinates
(and no quantization error).

Mike