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machinekit
Strange behaviour with HOME_SEARCH_VEL direction
Bas De Bruijn asked me to open a new issue and to refer to this google groups posting
lineardetla calibration i have not been able to calibrate the printer
the link to group
https://groups.google.com/forum/#!topic/machinekit/MRTmRa3saX0
thanks gary
I experienced the following. While the SEARCH_HOME_VEL was positive, while homing the direction was negative.
- meaning negative in motion (down)
- as well as negative in commands (the positions in the screen increased negatively, which match with going down)
Negating the HOME_SEARCH_VEL and HOME_LATCH_VEL to a - and a + which should be incorrect, but results in the right homing direction (up)
Then the next day, when I started up the config, the homing still went down. But now that the HOME_SEARCH_VEL in the ini file is negative, this is to be expected. So setting these to the correct values again + search_vel and - latch_vel gives the correct behaviour.
My system consists of a BBB rev C, BeBoPr-Bridge, recent build with commit 6ca42cfeb3de5c770041eb0c53a0fc931d7a3313
Does the build-plate move or the printing head? Sometimes the direction just looks wrong.
@gorf25 can you verify (and only this, don't look at scale and direction) that:
- HOME_SEARCH_VEL in your ini file is positive, like +10
- HOME_LATCH_VEL in your ini file is negative, like -1
- while homing the joints shows the positions of the joints being positive and increasing. like screenshow below, yellow box.
HOME_SEARCH_VEL in your ini file is positive, like +10 HOME_LATCH_VEL in your ini file is negative, like -1 while homing the joints shows the negative pos and moves towards the bed numbers decreasing,
HOME_SEARCH_VEL in your ini file is positive, like -10 HOME_LATCH_VEL in your ini file is negative, like +1 while homing the joints shows the positive pos and moves towards home joints being positive and increasing like your picture
I captured a situation where the search velocity is plain wrong. This time in 2 of the 3 joints. All should go up as per the INI file.
- I did a compile last week, from 0febbc7cf0934c287a7842bb57f19afdaecea92c
- printed w/o problems
- have had a long power down
for all joints I have these ini values.
HOME_SEARCH_VEL = 30
HOME_LATCH_VEL = -1
next step I did: changed the for the joints 0 and 2 the following:
HOME_SEARCH_VEL = -30
HOME_LATCH_VEL = 1
- pressing the home button moves all the joints up, with positive numbers in the preview window
- then homing didn't stop at the endswitch
- power down
- e-stop
- e-stop clear
- power up and then the joints 0 and 2 start moving down when I re-home.
- exit Machinekit
- change the ini values again to the correct ones
HOME_SEARCH_VEL = 30
HOME_LATCH_VEL = -1
- start Machinekit
- homing works as it should
I'm flabbergasted.
Will report back if I see something which triggers this.
verified your end stop signals are good before you started homing? Noticing you have ~30:1 difference there.
On Sun, Jun 7, 2015 at 2:58 PM, Bas de Bruijn [email protected] wrote:
next step I did: changed the for the joints 0 and 2 the following:
HOME_SEARCH_VEL = -30HOME_LATCH_VEL = 1
pressing the home button moves all the joints up, with positive numbers in the preview window
then homing didn't stop at the endswitch
power down
e-stop
e-stop clear
power up
and then the joints 0 and 2 start moving down when I re-home.
exit Machinekit
change the ini values again to the correct ones
HOME_SEARCH_VEL = 30HOME_LATCH_VEL = -1
- start Machinekit
- homing works as it should
I'm flabbergasted.
Will report back if I see something which triggers this.
— Reply to this email directly or view it on GitHub https://github.com/machinekit/machinekit/issues/601#issuecomment-109788461 .
good observation! If that were the problem it would be an embarrassing one :) I moved my board, and come to think of it, these exact joints were disconnected. I'll have to do some more rewiring so I'll be extra careful to check the endstops.