How would that SSI to quadrature encoder work? The nice thing about SSI is that when the power goes on, the motion system knows exactly where it is without homing or moving.
I'm trying to find an encoder now. The best I have found far on the surplus market is a 360 count per rev unit which is not very good. I'd like to find at least a 4096 count per rev unit or better yet a linear unit that I could actually use to mockup with a hydraulic cylinder. Dave On 5/25/2011 1:27 PM, Jon Elson wrote: > Dave wrote: > >>>> Does Mesa already >>>> >>>> >> handle >> this protocol? >> >> Peter said that they can get the data into the hardware but that there >> is no driver support for it yet. >> >> I need to get an SSI encoder. >> >> > Well, it seems like it wouldn't be all that hard to adapt my PPMC > encoder card to handle this > protocol, or maybe make an SSI to quadrature converter. If the SSI code > can be interrogated > fast enough, then the delay caused by converting serial to quadrature > won't bother the loop > stability much. I'm guessing from some of the data I read that the > encoder could be read out > perhaps every 20 us or so. > > The advantage of making an SSI to quadrature converter is that there > won't be any driver > issues, and then the encoder can be used with a variety of servo > systems. I have this board > that I made for Fanuc encoders, but it has both differential receivers > and drivers and a > Xilinx XC2C128 CPLD, which might have enough capacity to do the conversion. > > If you have a small encoder I could borrow for a few weeks, I would like > to give it a > try. > > > Jon > > ------------------------------------------------------------------------------ > vRanger cuts backup time in half-while increasing security. > With the market-leading solution for virtual backup and recovery, > you get blazing-fast, flexible, and affordable data protection. > Download your free trial now. > http://p.sf.net/sfu/quest-d2dcopy1 > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ vRanger cuts backup time in half-while increasing security. With the market-leading solution for virtual backup and recovery, you get blazing-fast, flexible, and affordable data protection. Download your free trial now. http://p.sf.net/sfu/quest-d2dcopy1 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
