dambacher-retrofit.de wrote: > Am 20.08.2010 18:55, schrieb Jon Elson: > >> dambacher-retrofit.de wrote: >> >>> Do you know if there is something similar for old philips glass scales? >>> >>> >> If these are analog scales of sufficient basic resolution, a comparator >> chip can be set up pretty easily to convert sine-wave scales to >> digital. Basically, they compare each signal to a set threshold, and if >> above it outputs a "1", if below, it gives a "0". >> > Hi Jon > I have no technical description of these, but the scale is verry corse (some > 0,3mm) and it has a number of pins to connect so I think it is one with > multiple > detectors in V Form. Using a microcontroller to sample this "grey code" like > signals and count like Andy did with the resolvers sounds good to me. I will > have to do an experiment... > OK, this is the type of scale used with an interpolator. It needs to measure the analog voltage of the two sine quadrature signals and then solve the equation to figure out the position on a circle the arcsin and arccos work out to. Then, you can convert the change from last reading into encoder count pulses. There are boxes sold to do this, but it could be cheaper to just buy a new scale with the desired resolution. Of course, if you want to tinker, it could become an entire project by itself!
Jon ------------------------------------------------------------------------------ This SF.net email is sponsored by Make an app they can't live without Enter the BlackBerry Developer Challenge http://p.sf.net/sfu/RIM-dev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
