On Thursday 27 March 2014 10:04:20 andy pugh did opine: > On 27 March 2014 09:50, Gene Heskett <[email protected]> wrote: > > What would be the usual way to toss a gear change constant into a > > servo speed control so that the PID.#.error band is relatively well > > centered in both gears? > > You could try using > http://www.linuxcnc.org/docs/html/man/man9/gearchange.9.html after the > PID and before the DAC.
That makes sense, with the stepup out of the PID being effective in the low speed range. I'll give that a shot, maybe today since they are promising temps with a + sign later today. > Alternatively there is "lincurve" for altering PID parameters on the > basis of something else. I will be re-inserting that also because the gemini still has a positive speed vs voltage in at the higher speeds above about 1/2 scale. Placed after the gearchange & before the DAC. > > > I have one input left that I could use to report a switch was closed > > by the lever being in high gear. > > On my mill I auto-detect the engaged gear (but I don't use any PID, I > just trust the DAC to be linear enough for my purposes.) > http://linuxcnc.org/hardy/dapper/index.php/english/forum/47-hal-examples > /27071-automatic-spindle-gear-detection That sounds neat too, but I don't think I need auto detection. Since I've only two speeds, a switch the lever twangs should be good enough. Thanks Andy. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
