Weird homing behavior. Y+Y2 out of sync

More
06 May 2022 12:04 #242127 by andypugh

That looks perfectly normal.

I am not sure that it does. It seems that the final moves to home happen separately. 

It might be more obvious if the HOME_POSITION was further from the end. But I am hesitant to suggest that in case there really is a problem and this pulls the gantry apart. 

Can you use Halscope to log the velocity of each Y joint and also the joint.N.home-state ?
(I suggest adding joint.0.is-homed as the halscope trigger) 
 
The following user(s) said Thank You: AJ

Please Log in or Create an account to join the conversation.

More
06 May 2022 13:35 - 06 May 2022 19:06 #242137 by snowgoer540

I am not sure that it does.


I agree, I slowed the video way down and they are happening separately.

I don't really follow your home/limit switch combination. It looks to me like you have:
home-y (input 001)
home-y2 (input 000)
home-x (input 002)
home-z (input 003)

The bit I'm confused on is:
max-x (input 004)
min-y (input 005)

What you are after can be achieved with 4 switches. If your axis travels lengths (MIN and MAX LIMIT) are properly input, unless you lose steps, you wont run past the max or the min. LinuxCNC sets and obeys these soft limits automatically.

Try using PNCCONF to set up the following:
input 000 -> Y2 Minimum Limit + Home
input 001 -> Y Minimum Limit + Home
input 002 -> X Minimum Limit + Home
input 003 -> Z Minimum Limit + Home (I think this is correct, but if it goes the wrong way then use Z Maximum Limit + Home)

I haven't seen anything but your hal and ini files, but I cant see an immediate reason why you need to use gpio.004 and gpio.005 as you did previously.

Also, your HOME_SEQUENCE (Z = 0, X = 1, Y and Y2 = -2) is correct, you can choose to do tandem axis last (-2 in your case).

For HOME_SEQUENCE, you are also not required to start at 0, and you can use the - sign on axes that are not tandem as well to designate that you don't want to be able to jog the axis until it is homed. In this example, you have to start the count at 1, because "-0" doesn't work. I choose to do this on my table so it cannot be jogged at all prior to homing (prevents crashes into hard stops, etc.). This is not well (maybe not at all) documented, but it does work fine.

My HOME_SEQUENCE entries to achieve this are as follows:
Z = -1
X = -2
Y and Y2 = -3
Last edit: 06 May 2022 19:06 by snowgoer540.
The following user(s) said Thank You: AJ

Please Log in or Create an account to join the conversation.

More
06 May 2022 14:23 #242142 by dgarrett
@AJ Please tell what branch you are using
and how and when it was last updated.

If you are using recent master branch, (after 2may22)
my recent commit may have caused this bad behavior.

Ref:
github.com/LinuxCNC/linuxcnc/commit/e5be0730d1c
 

Please Log in or Create an account to join the conversation.

More
06 May 2022 19:02 #242160 by tommylight
Yeah, slowing down the video does show everything, thank you Andy and Snowwy.
Also thank you Dgarret for always jumping in when we need you.
The following user(s) said Thank You: snowgoer540

Please Log in or Create an account to join the conversation.

More
06 May 2022 20:51 #242173 by AJ
Yes Andy, final moves do happen separately and I cannot have HOME_POSITION any further without breaking the gantry...
I had a go with Halscope today but no luck. Need a bit more time to get my head round on how it works. Will have another go tomorrow

Please Log in or Create an account to join the conversation.

More
06 May 2022 21:00 #242174 by AJ
snowgoer540,
I have wired the sensors without any particular order. I thought it would not matter?

As for
max-x (input 004)
min-y (input 005)
my thinking was that if anything would go wrong, these sensors would stop the machine before crashing. Are you saying these are obsolete and can be removed?

Please Log in or Create an account to join the conversation.

More
06 May 2022 21:07 #242175 by dgarrett
Repeating question:

@AJ Please tell what branch you are using
and how and when it was last updated.

If you are using recent master branch, (after 2may22)
my recent commit may have caused this bad behavior.

Please Log in or Create an account to join the conversation.

More
06 May 2022 21:12 #242176 by AJ

 @AJ Please tell what branch you are using
and how and when it was last updated.

If you are using recent master branch, (after 2may22)
my recent commit may have caused this bad behavior.
 

dgarret,
I have updated LinuxCNC very recently, couple days ago. I'm using version LinuxCNC v2.9.0 QtPlasmaC v1.223.187

Please Log in or Create an account to join the conversation.

More
06 May 2022 21:24 #242178 by dgarrett
ok -- i've reverted the suspicious commit
if you built from git, you must rebuild
if you used buildbot deb, it usually takes a few hours

ref:
github.com/LinuxCNC/linuxcnc/commit/3b17ed1d9c

buildbot status:
buildbot.linuxcnc.org/buildbot/grid
The following user(s) said Thank You: tommylight, Clive S, AJ

Please Log in or Create an account to join the conversation.

More
07 May 2022 06:53 #242208 by AJ

 ok -- i've reverted the suspicious commit
if you built from git, you must rebuild
if you used buildbot deb, it usually takes a few hours

 

All good! I can now park the gantry anywhere I want after homing and both Y1 & Y2 move in tandem.
Thank you!
The following user(s) said Thank You: Clive S

Please Log in or Create an account to join the conversation.

Time to create page: 0.161 seconds
Powered by Kunena Forum