Homing with gantry and absolute encoders
- mlhilligsoe
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I can manually square the system and store the encoder offset in the encoders themselves, in order to avoid any squaring through linuxcnc.
Right now LinuxCNC (master/devel + Axis) boots into joint mode, and I then have to manually home each joint. Is there a way to avoid this when using absolute encoders?
Also I tried using the HOME_ABSOLUTE_ENCODER configuration setting, but doesn't seem to do anything and I don't know why?
I will upload .hal and .ini files if requested.
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So, I think we do need to see your INI file.
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I could join in asking to check my .ini. I don't want to start a new thread.
I have ASDA-A2 with absolute encoders. If I manually move the X axis after switching off, I will load the original position instead of the original position + manual relocation when I turn it on. So I don't know where my mistake is.
Can you advise me?
Thank you very much.
jirka
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... will load the original position instead ...
possibly due to:
[TRAJ]
POSITION_FILE = position.txt
POSITION_FILE = position.txt - If set to a non-empty value,
the joint positions are stored between runs in this file.
This allows the machine to start with the same coordinates
it had on shutdown. This assumes there was no movement of
the machine while powered off. If unset, joint positions are
not stored and will begin at 0 each time LinuxCNC is
started. This can help on smaller machines without home
switches. ...
Ref: linuxcnc.org/docs/2.8/html/config/ini-config.html
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If there is no "POSITION_FILE = position.txt", it is always loaded with "X0 Y0 Z0". As if there were no absolute encoders.
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works: net x-pos-fb <= lcec.0.x.enc-pos-enc
i had: net x-pos-fb <= lcec.0.x.enc-pos
Thanks
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- CNCCustoms
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How does Absolute encoder homing work? Is there a way to show the joint position as a comparison to the absolute encoder all the time (i.e. if I move the motors manually while the machine is off, the position is updated when linuxcnc starts up again?)
My home switches are not fantastically accurate so I would like to make use of the always powered absolute encoders I have on my motors.
I'm running in Step gen and not using closed loop/ velocity mode.
Any help will be greatly appreciated.
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Just look for the HOME_ABSOLUTE_ENCODER options here:
linuxcnc.org/docs/2.8/html/config/ini-co...t__lt_num_gt_section
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