Tuning Servos with a 7i77
12 Jun 2021 18:31 - 12 Jun 2021 18:35 #211879
by BigJohnT
Tuning Servos with a 7i77 was created by BigJohnT
While I was getting the replacement servo on the BP to work I wanted to update the configuration using what I have been reading on the forum to end up with FF1 == 1.
X and Y axis work fine, however Z will just jump back and forth when I try and jog it. Z seems fine if I comment out the analogout2-scalemax, analogout2-minlim and analogout2-maxlim in the hal file.
X and Y have the same ratio of 1 to 0.667 with 0.200" per rev ballscrew and 2400 RPM servos. I calculated the maximum velocity for them to be 5.333. per second
The only difference on Z is the ratio which is 1 to 0.566 and I calculate the maximum velocity per second of 4.444.
I've attached the ini and hal files as well as the spreadsheet I used to get my numbers.
Thanks
JT
X and Y axis work fine, however Z will just jump back and forth when I try and jog it. Z seems fine if I comment out the analogout2-scalemax, analogout2-minlim and analogout2-maxlim in the hal file.
X and Y have the same ratio of 1 to 0.667 with 0.200" per rev ballscrew and 2400 RPM servos. I calculated the maximum velocity for them to be 5.333. per second
ENCODER_SCALE = -30000
OUTPUT_SCALE = 5.333
OUTPUT_MIN_LIMIT = -5.333
OUTPUT_MAX_LIMIT = 5.333The only difference on Z is the ratio which is 1 to 0.566 and I calculate the maximum velocity per second of 4.444.
ENCODER_SCALE = -35500
OUTPUT_SCALE = 4.444
OUTPUT_MIN_LIMIT = -4.444
OUTPUT_MAX_LIMIT = 4.444I've attached the ini and hal files as well as the spreadsheet I used to get my numbers.
Thanks
JT
Last edit: 12 Jun 2021 18:35 by BigJohnT.
The following user(s) said Thank You: tommylight
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10 Oct 2021 17:51 #222784
by nkp
But the parameters still contain some default value (??)
Even if you comment them out in the file.
Replied by nkp on topic Tuning Servos with a 7i77
Z seems fine if I comment out the analogout2-scalemax, analogout2-minlim and analogout2-maxlim in the hal file.Even if you comment them out in the file.
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10 Oct 2021 22:12 #222801
by PCW
Replied by PCW on topic Tuning Servos with a 7i77
Yes, all parameters have a default value.
I would expect scalemax, maxlim, minlim to default to 10,10,-10
on a 7I77 (scaled in volts)
I would expect scalemax, maxlim, minlim to default to 10,10,-10
on a 7I77 (scaled in volts)
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