Stuart Stevenson wrote: > > My first thought was to control the spindle with the MPG and have the Z (or > other linear axis) scaled to the correct feedrate. With the MPG controlling > the spindle the reversal should not need to be as abrupt. > You can make the spindle reversal as smooth as you like, as long as there is a DAC output from EMC2 to control the spindle drive. You put a filter component (either lowpass or limit) between the commanded spindle speed (which changes abruptly) and the velocity input to the VFD. This works great. See http://pico-systems.com/codes/jebport/ppmc_motion.hal
but mostly it looks like this : # set up 4th DAC generator as a spindle speed control newsig spindle-speed float newsig spindle-DAC-cmd float newsig spindle-DAC-filt float newsig spindle-DAC-abs float linkps motion.spindle-speed-out => spindle-speed linksp spindle-speed => mult2.1.in0 setp mult2.1.in1 0.002457 linkps mult2.1.out => spindle-DAC-cmd linksp spindle-DAC-cmd => lowpass.0.in linkps lowpass.0.out => spindle-DAC-filt setp lowpass.0.gain 0.005 linksp spindle-DAC-filt => abs.0.in linksp spindle-DAC-abs => abs.0.out linksp spindle-DAC-abs => ppmc.0.DAC.03.value This uses the old hal syntax. I feed the absolute of the filtered speed command to the drive as this one expects only 0-10 V magnitude on the speed input. Hmmm, still seems like the forward/reverse relays would flip immediately and not wait for the analog output to ramp down, but it seems to work on my drive. Maybe it ignores the direction reversal until the speed command has ramped down. I used lowpass as I was familiar with it. limit would be smoother, with a constant rate of accel/decel. Jon ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
