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Carousel with analog servo drive
1 year 10 months ago #316884
by lukin1156
Carousel with analog servo drive was created by lukin1156
Hello everyone, I am starting up an automatic tool change on my new milling machine and I have a problem connecting the carousel component. The carousel is rotated by a servo motor that I control with an analog signal. There is a gear transmission of unknown ratio between the motor and the carousel. There are two inductive sensors on the carousel for sensing the index and the tool position. Currently, the carousel rotates to the index after enabling. When entering the pocket number, the carousel rotates to the selected position, but only based on the number of encoder pulses, it ignores the tool position sensor. The signal for the motor goes through a PID loop, named pid.c. Should I unlink the encoder from the carousel component and connect the encoder only to the PID loop?
Code:
loadrt carousel pockets=6 encoding=index dir=2
addf carousel.0 servo-thread
net carousel-index carousel.0.sense-0 hm2_5i25.0.7i77.0.0.input-03-not
net carousel-pulse carousel.0.sense-1 hm2_5i25.0.7i77.0.0.input-02-not
net carousel-enable <= motion.digital-out-05 => carousel.0.enable
net carousel-pocket <= motion.analog-out-00 => conv-float-s32.0.in
net carousel-pocket-out <= carousel.0.pocket-number => conv-float-s32.0.out
# PID carousel
setp pid.c.Pgain [JOINT_3]P
setp pid.c.Igain [JOINT_3]I
setp pid.c.Dgain [JOINT_3]D
setp pid.c.bias [JOINT_3]BIAS
setp pid.c.FF0 [JOINT_3]FF0
setp pid.c.FF1 [JOINT_3]FF1
setp pid.c.FF2 [JOINT_3]FF2
setp pid.c.deadband [JOINT_3]DEADBAND
setp pid.c.maxoutput [JOINT_3]MAX_OUTPUT
setp pid.c.error-previous-target true
net c-index-enable => pid.c.index-enable
net machine-is-enabled => pid.c.enable
net c-pos-cmd => pid.c.command
net c-pos-fb => pid.c.feedback
net c-output <= pid.c.output
# ---PWM Generator signals/setup---
setp hm2_5i25.0.7i77.0.1.analogout3-scalemax [JOINT_3]OUTPUT_SCALE
setp hm2_5i25.0.7i77.0.1.analogout3-minlim [JOINT_3]OUTPUT_MIN_LIMIT
setp hm2_5i25.0.7i77.0.1.analogout3-maxlim [JOINT_3]OUTPUT_MAX_LIMIT
net c-output => hm2_5i25.0.7i77.0.1.analogout3
net c-pos-cmd <= carousel.0.counts-target
# ---Encoder feedback signals/setup---
setp hm2_5i25.0.encoder.03.counter-mode 0
setp hm2_5i25.0.encoder.03.filter 1
setp hm2_5i25.0.encoder.03.index-invert 0
setp hm2_5i25.0.encoder.03.index-mask 0
setp hm2_5i25.0.encoder.03.index-mask-invert 0
setp hm2_5i25.0.encoder.03.scale [JOINT_3]ENCODER_SCALE
net c-pos-fb <= hm2_5i25.0.encoder.03.position
net c-vel-fb <= hm2_5i25.0.encoder.03.velocity
net c-pos-fb => conv-float-s32.1.in
net c-pos-fb-out => conv-float-s32.1.out => carousel.0.counts
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1 year 10 months ago #316885
by andypugh
Replied by andypugh on topic Carousel with analog servo drive
Does your PID control velocity or position? It would need to control velocity to work as intended with the carousel component.
The use the carousel.N.motor-vel output as the (velocity) PID command.
Now the component will derive the tool number from the index and tool pule inputs, and will simply drive the carousel motor at constant speed until the it sees the sensor for the selected too.
It _might_ work better in counts mode based on the encoder in the servo motor, but try it this way first.
The use the carousel.N.motor-vel output as the (velocity) PID command.
Now the component will derive the tool number from the index and tool pule inputs, and will simply drive the carousel motor at constant speed until the it sees the sensor for the selected too.
It _might_ work better in counts mode based on the encoder in the servo motor, but try it this way first.
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1 year 9 months ago #318888
by lukin1156
Replied by lukin1156 on topic Carousel with analog servo drive
I tried using the speed mode, but it didn't work. So I went back to the original control. By manually rotating the carousel, I determined the number of pulses between the individual pockets. The automatic tool change works quite well, sometimes there is just a problem with homing the carousel. If the carousel goes to the same side at the home position, it is fine. However, if the carousel goes to the other side after homing, there is a small error in the position. I tried using rotation in only one direction, but there is another problem that the error in the number of pulses between the individual pockets adds up over time.
Here is short video from tool change.
youtube.com/shorts/BAgzHO6OKA0?si=I7e9RTFSHqlaFPUl
Here is short video from tool change.
youtube.com/shorts/BAgzHO6OKA0?si=I7e9RTFSHqlaFPUl
Code:
# --- automatic tool change ---
loadrt carousel pockets=6 encoding=index dir=2
addf carousel.0 servo-thread
setp carousel.0.scale 1666
setp carousel.0.home-offset -70
net spindlenot <= halui.spindle.0.is-on => not.0.in
net spindlenotout <= not.0.out => and2.2.in0
net toolunlock <= motion.digital-out-00 => or2.1.in0
net toolunlockkey <= hm2_5i25.0.7i84.0.2.input-07 => or2.1.in1
net toolunlockout <= or2.1.out => and2.2.in1
net toolunlockout1 <= and2.2.out => hm2_5i25.0.7i77.0.0.output-00
net carouselup <= motion.digital-out-01 => hm2_5i25.0.7i77.0.0.output-01
net spindleair <= motion.digital-out-02 => hm2_5i25.0.7i77.0.0.output-02
net orient1 <= motion.digital-out-03 => hm2_5i25.0.7i77.0.0.output-12
net orient2 <= motion.digital-out-04 => hm2_5i25.0.7i77.0.0.output-13
net toolisunlock <= motion.digital-in-00 => hm2_5i25.0.7i77.0.0.input-04
net toolislock <= motion.digital-in-01 => hm2_5i25.0.7i77.0.0.input-05
net carouselisup <= motion.digital-in-02 => hm2_5i25.0.7i77.0.0.input-06
net carouselisdown <= motion.digital-in-03 => hm2_5i25.0.7i77.0.0.input-07
net spindleinposition <= motion.digital-in-04 => hm2_5i25.0.7i77.0.0.input-24
net carousel-index carousel.0.sense-0 hm2_5i25.0.7i77.0.0.input-03-not
net carousel-pulse carousel.0.sense-1 hm2_5i25.0.7i77.0.0.input-02-not
net carousel-enable <= motion.digital-out-05 => carousel.0.enable
net carousel-pocket <= motion.analog-out-00 => conv-float-s32.0.in
net carousel-pocket-out <= carousel.0.pocket-number => conv-float-s32.0.out
net carousel-finish <= motion.digital-in-08 <= carousel.0.ready
# PID carousel
setp pid.c.Pgain [SPINDLE_2]P
setp pid.c.Igain [SPINDLE_2]I
setp pid.c.Dgain [SPINDLE_2]D
setp pid.c.bias [SPINDLE_2]BIAS
setp pid.c.FF0 [SPINDLE_2]FF0
setp pid.c.FF1 [SPINDLE_2]FF1
setp pid.c.FF2 [SPINDLE_2]FF2
setp pid.c.deadband [SPINDLE_2]DEADBAND
setp pid.c.maxoutput [SPINDLE_2]MAX_OUTPUT
setp pid.c.error-previous-target true
net c-index-enable => pid.c.index-enable
net machine-is-enabled => pid.c.enable
net c-vel-cmd => pid.c.command
net c-pos-fb => pid.c.feedback
net c-output <= pid.c.output
# ---PWM Generator signals/setup---
setp hm2_5i25.0.7i77.0.1.analogout3-scalemax [SPINDLE_2]OUTPUT_SCALE
setp hm2_5i25.0.7i77.0.1.analogout3-minlim [SPINDLE_2]OUTPUT_MIN_LIMIT
setp hm2_5i25.0.7i77.0.1.analogout3-maxlim [SPINDLE_2]OUTPUT_MAX_LIMIT
net c-output => hm2_5i25.0.7i77.0.1.analogout3
net c-vel-cmd <= carousel.0.counts-target
# ---Encoder feedback signals/setup---
setp hm2_5i25.0.encoder.03.counter-mode 0
setp hm2_5i25.0.encoder.03.filter 1
setp hm2_5i25.0.encoder.03.index-invert 0
setp hm2_5i25.0.encoder.03.index-mask 0
setp hm2_5i25.0.encoder.03.index-mask-invert 0
setp hm2_5i25.0.encoder.03.scale [SPINDLE_2]ENCODER_SCALE
net c-pos-fb <= hm2_5i25.0.encoder.03.position
net c-vel-fb <= hm2_5i25.0.encoder.03.velocity
net c-pos-fb => conv-float-s32.1.in
net c-pos-fb-out => conv-float-s32.1.out => carousel.0.counts
net tool-changed <= iocontrol.0.tool-change => iocontrol.0.tool-changed
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1 year 9 months ago #318894
by PCW
Replied by PCW on topic Carousel with analog servo drive
If it's losing counts you might try decreasing the encoder sample rate
(which has the effect of increasing the input filter time constant)
Since this is global and affects all axis, one trick is to decrease the sample
rate by a factor of 5 and disable the encoder filter on all but the tool changer
encoder. (keeping the main axis encoders with the same filter time but
increasing the tool changer encoder filter time constant by a factor of 5)
(which has the effect of increasing the input filter time constant)
Since this is global and affects all axis, one trick is to decrease the sample
rate by a factor of 5 and disable the encoder filter on all but the tool changer
encoder. (keeping the main axis encoders with the same filter time but
increasing the tool changer encoder filter time constant by a factor of 5)
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