On Sat, 10 Sep 2011 23:06:08 -0500, Jon Elson wrote:
Ignoramus13208 wrote:
On 2011-09-10, Lloyd E. Sponenburgh wrote:

What do you think of the idea of having absolute positioning
information in EMC, rather than the "dead reckoning" positioning
provided by screws of unknown accuracy? Do you know if anyone else has
approached it this way? (i.e. - taken a DRO, and used it for the
positioning info?)
....
Lloyd, this will work just fine. It is a known approach. If your DRO is
absolute, you can also avoid homing.

Well, if he has 1 uInch encoder resolution, then at 60 IPM he will have
a million encoder counts/second. That is fairly fast. Also, how will
he read this into EMC2? An existing quadrature encoder counter, or is
Lloyd going to build something custom to read the absolute data?

In another post, Lloyd said resolution on one of the scales is
1 micron, rather than 1 microinch. At a million microns per meter,
1 micron is about 40 microinches. (.000039370")

--
jiw