On Friday 15 June 2018 20:20:20 jeremy youngs wrote: > Always another hurdle . Lol. I abandoned the h bridge plan for now as > I am lacking sufficient power supply. I have 2 aerotech 4020 linear > drives . The issue is they need tachometer feedback and it appears > though the drive isn't configured for armature feedback. So the > question is, is there a readily available device to convert 1000 ppr > to an analog signal @7v /1000 rpm ? > > The drive is configurable to torque mode, would it be easier to set > drive in torque mode and tune servo in Linux CNC with 7i90 ? > Thanks
Put a 1000 line encoder on the motor, and use the encoders in the 7i90 to do a position servo. The aerotech drive is line powered, 20 amps max, 40 volts max. And it has inputs for an encoder, taking lcnc out of the circuit if you'd like. But I'd druther put the encoder into linuxcnc, and let it calculate the pwm or pdm drive needed for a position null. I think it would be more precise, and possibly faster. Aerotech mentions using 741's (op-amps) but the gain of a 741 above 10 hz falls like a rock, and that leaves the nyquist phase v stability angles in doubt. I don't see a reason why, if the correct motors are used, that it cannot be made to work. > ---------------------------------------------------------------------- >-------- Check out the vibrant tech community on one of the world's > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users -- Cheers, Gene Heskett -- "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> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
