I assume they use a De Bruijn sequence < https://en.wikipedia.org/wiki/De_Bruijn_sequence> with perhaps a manchester encoding to guarantee frequent edges.
All you have to do on startup is to see N bits. That will tell you the absolute position. Then interpolate some bit edges using a camera of appropriate resolution. That would add additional bits. I have the parts for a laser interferometer sitting in my parts bin. Maybe it's time to fire it up and make some glass scales. What edge resolution can I get with a cheap camera/microscope? Ken On Fri, Aug 7, 2015 at 6:16 PM, andy pugh <bodge...@gmail.com> wrote: > On 7 August 2015 at 12:23, EBo <e...@sandien.com> wrote: > > Possibly, but I cannot tell from the information Renishaw published in > > that brochure. > > I think that the target is a barcode. The head can see enough barcode > to tell exactly where it is on the code sequence to within one bar, > then looks at the absolute position of the bars in the viewing area > to work out the rest of the bits of data. > > > -- > atp > If you can't fix it, you don't own it. > http://www.ifixit.com/Manifesto > > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-developers mailing list > Emc-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-developers > -- Kenneth Lerman 55 Main Street Newtown, CT 06470 ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
