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Ehsan_R wrote:

Yes, I tested this before, but it did not make a difference in the result
 

There may be other issues, but you must have
HOME_INDEX_NO_ENCODER_RESET = YES
if the feedback position is not cleared on index

(AFAIK The stepgen knows nothing about the encoder index)

With hostmot2 firmware you can use the stepgen with an index
(That clears the stepgen feedback position in the expected way)
but you then connect the stepgen index enable hal pin to the
joint index enable pin. I have no idea if LitexCNC has a similar
feature.

yeah when you are running at high speeds heat is a real pain in the butt. i use Kool mist which is pretty safe all around. it's not the cheapest but a little goes a long way. it only takes 4 oz per gallon to mix up and a gallon costs around $50 in my neck of the woods.

Dang it my parts are rusting... I really need to start building the mill or i will be left with a pile of rust!
I had no idea mist can help that much, i was aware it helps a bit with cooling, but this is far better than what i imagined.
Thank you, great job and the last pass sounds nice at 4X speed with youtube playing at 2X speed

loving the progress on this, keep up the hard work cant wait to see a version to try my self..

Ehsan_R wrote:

This is how I configured the ini and hal files.

net home-x => joint.n.home-sw-in
net x-index-enable    joint.n.index-enable     encoder.n.index-enable

And

[code]HOME_OFFSET = 0
HOME_SEARCH_VEL = 1
HOME_LATCH_VEL = -0.1
HOME_USE_INDEX = Yes
HOME = 0
HOME_SEQUENCE = 0

1. the hal part will not work as you posted it here, the "n" must be a number, not N, it is there to denote that must be the joint number, so 0, 1, 2, 3.... in your case probably 0 as it is axis X
2. the ini part, what is the HOME set to?
I would assume from your reply at 20, set it to 0 if that is the case.

With great speed comes great weldability



 

Ehsan_R wrote:

Hello
I just connected the z pulse signal from the encoder and I want to use it for homing.
(A, B are not connected) Open loop system
This is how I configured the ini and hal files.

net home-x => joint.n.home-sw-in
net x-index-enable    joint.n.index-enable     encoder.n.index-enable

And

[code]HOME_OFFSET = 0
HOME_SEARCH_VEL = 1
HOME_LATCH_VEL = -0.1
HOME_USE_INDEX = Yes
HOME = 0
HOME_SEQUENCE = 0

But when the homing command is sent, the joint moves until it reaches the homing switch (for example, position x=20), then the axis value immediately becomes zero and moves in the opposite direction until it reaches the index pulse, and when the index pulse is received, the axis value is set to 20 and moves at maximum speed until it reaches zero.
What should I do if I want the joint to stop immediately upon receiving the index pulse and consider that point as the origin?
Is not connecting the encoder the reason for this last movement?
 

[/code]

Does anyone have any ideas or suggestions to solve this problem?

I use a servo motor
What do you mean by enabling signal?
How do I connect it?
Even if I disable the motors, the position of the axes changes
I don't want the position of the axis to change every time I close the software or press the power button or e stop
Please see this post to understand what I mean
github.com/Peter-van-Tol/LiteX-CNC/discu...ssioncomment-9351198

Hilfe mit was?
Was fuhr ein fehler gibt?

Might want to try the MachineKit forums, they use BBB, we do not, although MachineKit is a fork of LinuxCNC.

Fedora is being developed quite rapidly, about 4 months ago i gave it a try, the touchscreen stuff worked by far the best on it, but the boot time is still about 2-3times longer than Mint, and uses RPM while i am used to command line APT.
Still, knowing it works on it is satisfying, so thank you.

You may have a problem with input isolated signals - not good for a "noisy" environment. The 5-axis Chinese controller uses the same simplified scheme. What drivers are you using? Do you have movement at first power on the control board? Why are you ignoring the enabling signal?

If you want the the tool velocity (X,Y,Z)  you can use motion.current-vel

If you want just X,Y as rodw says you can use Pythagoras
(see the hypot hal component)

Hi JT,

I already ordered one from Peter but thanks for letting me know you have them in stock.

I might want to isolate at the source instead.
I think the main problem is that the drive is not isolated. The power ground is shared with it's internal low voltage ground.
One workaround I'm looking at is running the drive in current mode and not splitting the encoder back to the drive. The catch with that is the hall sensor ground is still shared at the motor encoder. Could I add a simple opto isolator board to isolate the encoder from the 7i77 and drive/motor? 

Any idea if this could play nicely with the 7i77 encoder inputs? Motor encoder has 1500 count running at 3000 rpm. I didn't see a spec on timing.

Donker optocupler:

www.amazon.com/Optocoupler-Isolation-Mod...erter/dp/B08LYQQ7X6/


 

Hi,

Thanks Tommy, it helped.

Just finished the test on the production machine.

In the beginning i had some problems, but after a few hours of coding and testing everything went more or less ok.
So in the end, this test is succesfull.

This test was using the tpmod_scurve_grotius.so component. This component used no look ahead and was
using low delta values for the gbrl algoritme.

The component used no back-end scurve runners. The stepgen was directly attached at the tpmod_scurve_grotius.so
output values.

A few things i learned :
- Don't press stop button when machine is moving. Better press pause button as stop can trigger a joint follow error.
- Home all axis before jogging machine, sometimes the dual x axis motors won't run together if not homed.
- The maximum values of this parport driven machine : maxjerk 7500, maxacc 1000, maxvel 10000.
- Change the jerk value when machine is not moving, if doing it while moving linuxcnc can freeze.

A few things made me happy :
- The bigger arc's in the program, the machine moved quite nice.
- The program was running quite stable, restart ok, pause ok. The linuxcnc program flow seems to work properly.

The video :