On 28 January 2014 00:34, Greg Bentzinger <[email protected]> wrote:
> An idea I had was to do something like that when trying to read high count > encoders at higher speeds. Once the velocity has passed a given threshold it > is known which direction an axis is moving so at that point is Quad still > really needed? Could you just continue to count the leading edge for A and > use that for velocity tracking? Depending on the application you might consider using two software encoder functiions, one in "counter mode" working on a single channel to report speed, and a second one in quadrature mode to accurately measure position at lower speeds. I think this would work well for a lathe spindle, where feed-per-rev uses the spindle-speed-in input, and threading uses the spindle-revs (position) input. I don't think anything uses both, so if they get out of synch it doesn't matter. If you wanted to do this for an actual axis then I think it would be possible in HAL, by carefully combining the outputs of the two encoders (probably using latches and muxes) -- atp If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ WatchGuard Dimension instantly turns raw network data into actionable security intelligence. It gives you real-time visual feedback on key security issues and trends. Skip the complicated setup - simply import a virtual appliance and go from zero to informed in seconds. http://pubads.g.doubleclick.net/gampad/clk?id=123612991&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
