5 axis CNC Router/3d printer

Moderators: TomKerekes, dynomotion

Post Reply
User avatar
TomKerekes
Posts: 2527
Joined: Mon Dec 04, 2017 1:49 am

Re: 5 axis CNC Router/3d printer

Post by TomKerekes » Sat Jan 21, 2023 7:21 pm

Hi George,
I opened one of the sample files and an error
message came up saying there was a file missing. Screen came on and there was no viewer and the controls where also missing, so I could not go back and reset the screen.
You should always be able to right click the title bar to get to the Tool Setup Screens.
That is why I was wondering where the data was store so I could try reloading.
Oops sorry I missed that question. The configuration is stored in \KMotion\Data\GCodeConfigCNC.txt (and GCodeConfigCNC.txt.bak)

The simplest thing is to restore all files in the \KMotion\Data folder. See also here.

Strange. I can't see how re-loading software would do anything unless something was now set differently.
One thing I did notice was as the axis rotates there is a small amount of jitter. Is there any way to get that out?
When running GCode? Can you be more descriptive? Are the axes well tuned in KMotion.exe?
Regards,

Tom Kerekes
Dynomotion, Inc.

George Butty
Posts: 102
Joined: Sun Mar 22, 2020 9:36 pm

Re: 5 axis CNC Router/3d printer

Post by George Butty » Mon Jan 23, 2023 2:01 am

Hi Tom, I ran a simple Gcode to rotate B45 and then C180 and then return to 0 on both axis with RTCP on.
The C axis has a jitter that comes and goes at a low speed. It starts a small shake and goes away then starts
the same shake again little latter. It's like a harmonics until it stops moving. Running C axis in jog mode with
with RTCP off does not do this. You asked about tuning. The Teknic motors run as steppers so there is no feedback
for position. I only tuned the motors using the Teknic software. Is there something I can do in Kmotion as well.
I don't have any values in the IIR filters. I know about tuning if running with feed back. Would that make a difference?
Thanks
George

User avatar
TomKerekes
Posts: 2527
Joined: Mon Dec 04, 2017 1:49 am

Re: 5 axis CNC Router/3d printer

Post by TomKerekes » Mon Jan 23, 2023 3:02 am

Hi George,
I ran a simple Gcode to rotate B45 and then C180 and then return to 0 on both axis with RTCP on.
The C axis has a jitter that comes and goes at a low speed. It starts a small shake and goes away then starts
the same shake again little latter. It's like a harmonics until it stops moving. Running C axis in jog mode with
with RTCP off does not do this.
You are confusing me. Are you running GCode or Jog mode? Please test with RTCP on and off with GCode.
The Teknic motors run as steppers so there is no feedback for position.
So I assume all axes are configured for Step/Dir mode. In that mode PID Feedback or IIR Filters are not used. You might Post your Init Program.
Is there something I can do in Kmotion as well.
No

There are ways to capture what is actually being commanded to the motors for a motion. Such as:
C:\KMotion435h\C Programs\CaptureXYZMotionToFile.c

this could be expanded to include B and C. This data can then be plotted in something like Excel to see if there are any anomalies.

It sounds like the Teknic servos are tuned marginally. But I wouldn't expect those to behave differently if XY are moving concurrently or not.
Regards,

Tom Kerekes
Dynomotion, Inc.

George Butty
Posts: 102
Joined: Sun Mar 22, 2020 9:36 pm

Re: 5 axis CNC Router/3d printer

Post by George Butty » Tue Jan 24, 2023 2:44 am

Hi Tom, Yes I ran the Gcode in RTCP ON (G43.3) and also compared to running C axis in jog mode ( arrow) with RTCP OFF (G49).
and yes there is a slight shake with RTCP ON and no shake with RTCP OFF.
Yes all axis is running in Step/ Direction set on the Tecknic motors and in the Init. file. That is the setting needed to run them but in
Step/Direction mode, the motors have an option to receive Quad signals instead which is what I am doing.
Unfortunately my motor fault problem has returned. Yes it was too easy just to reload the software! I also connected to
Ch0 to send signals to both motors and did not make a difference. There is another method for tuning the slaved
motors and will need to contact Tecnic for that. I will focus on tuning at the moment and see where that leads.
Also I am running Ver 434. should I update to 435h ? If so, can you send link.
Thanks
George

User avatar
TomKerekes
Posts: 2527
Joined: Mon Dec 04, 2017 1:49 am

Re: 5 axis CNC Router/3d printer

Post by TomKerekes » Tue Jan 24, 2023 10:55 pm

Hi George,
Yes I ran the Gcode in RTCP ON (G43.3) and also compared to running C axis in jog mode ( arrow) with RTCP OFF (G49).
and yes there is a slight shake with RTCP ON and no shake with RTCP OFF.
Sorry, It still isn't clear when it does it and when it doesn't. There are 4 situations.

Which axis is the "shake" in?

So you are only commanding B to move? When Jogging B with RTCP off the B Motion should be at the Jog Speed. With RTCP on the speed of the B axis may be slower if the XYZ axes need to travel faster than their limits (Velocity and acceleration). Maybe a velocity/acceleration difference is the cause?
Unfortunately my motor fault problem has returned. Yes it was too easy just to reload the software
Again a problem coming and going without changes tends to indicate something very marginal.
Also I am running Ver 434. should I update to 435h ? If so, can you send link.
Here
Regards,

Tom Kerekes
Dynomotion, Inc.

George Butty
Posts: 102
Joined: Sun Mar 22, 2020 9:36 pm

Re: 5 axis CNC Router/3d printer

Post by George Butty » Tue Jan 31, 2023 3:03 am

Hi Tom, sorry for taking so long to get back to you . Still struggling with X1 axis faulting. Had it running nice on Friday but no luck today.
Did every thing I could think of to get the problem to shift to another axis so I could isolate the problem. Interchanged parts and wiring with no luck.
Today I decided to connect my scope to the Kflop output to see if I could catch a bad signal. I connected the Tecknic motor to there software to
monitor the fault. I comes up with a Step input timing error every time when fault accurse. Connected scope to ch0 X1 axis, output 28and 29, JP5 pin 1 and 2 and output pin 36 and 37. This is the 3.3 TTL PNP output. Set scope to capture start of first pulse. Ran RTCP first time and got nice clean Quad
signal. Ran RTCP a couple of more time and finally captured a bad signal and motor faulted as well. Attached picture of scope and Teknic fault.
Still running ver 434. Any idea what is causing this?
George
Attachments
20230130_114504.jpg
20230130_170558.jpg

User avatar
TomKerekes
Posts: 2527
Joined: Mon Dec 04, 2017 1:49 am

Re: 5 axis CNC Router/3d printer

Post by TomKerekes » Tue Jan 31, 2023 7:26 pm

Hi George,

I can't really follow what you are doing and you aren't answering some of my questions. Please specify step by step what are you doing and what happens. What do the DROs indicate before and after the fault?

The scope seems to show a burst of high frequency pulses. Maybe 1 MHz? KFLOP may do that when the trajectory is discontinuous. Something such as the axis is at say 1 inch and some motion begins starting at 2 inches. This would result in an "infinite" speed jump to 2 inches.

Are you still using the unmodified CKinematics5AxisGimbalCB?

Are you calling your X Master/Slave axis X1 and X2?

Where was the scope connected when you saw that?

I would try Version 4.35g. Although no changes were made to CKinematics5AxisGimbalCB.
Regards,

Tom Kerekes
Dynomotion, Inc.

George Butty
Posts: 102
Joined: Sun Mar 22, 2020 9:36 pm

Re: 5 axis CNC Router/3d printer

Post by George Butty » Tue Jan 31, 2023 8:34 pm

Hi Tom, this signal is at the start of the RTCP motion. I captured the signal coming directly out of the Kflop. Please read my last post again. I am very specific about the scope connection. This is the master signal ch0 which I call X1 which is directly read from the Kflop output (3.3v). X2 is the slave. The DRO's read close to zero for the xyz axis and show the angle of the B and C axis rotation. The DRO XY values do not come back to zero once the program cycle is complete. Yes I am still using the unmodified CKinematics5AxisGimbalCB. I am assuming the values are not coming to zero because I have not set the new CKinematics file. Also I do not have the fault signal output programed yet therfore X Axis stops moving but the rest continue. DRO continues like if nothing happened.

This is the program I run in RTCP:
G49 G40 G54
G20 T1001 M06
G43.4 H1001 (H value 4)
G01 F1000
B45
C90
C-180
B0 C0
M30

It looks like I found the problem and it seems to be the ch0 output. Here Is a video of the signal coming from the 3.3v output on Kflop at the START of the RTCP program stated above. Soon as I hit the the green cycle start, a bad high frequency signal is triggered from Ch0. This is for a very short time and then the normal Quad signal starts. Once the High Frequency signal is started, the X1 master motor Faults causing X2 to fault right after.
See attached link to Video. Pay attention to to start of the cycle. https://www.youtube.com/shorts/SQy57V_Ydks
So today I reconfigured the Master/Slave to run only off Ch1 with the Quad signals from both motors connected to CH1. Therefore Ch1 is sending
signals to both motors at the same time. Also connected scope to Ch1 directly coming out of Kflop. So far getting no faults and getting perfect
Quad signals every time program starts.

George

User avatar
TomKerekes
Posts: 2527
Joined: Mon Dec 04, 2017 1:49 am

Re: 5 axis CNC Router/3d printer

Post by TomKerekes » Wed Feb 01, 2023 1:28 am

Hi George,

I was able to reproduce that in Version 4.34. I think it has to do with switching RTCP on/off while BC not at Zero resulting in a "quantum leap".

That issue was fixed in Version 4.35e. Please use Version 4.35h

For me the issue (burst of pulses) is perfectly consistent and occurs on both the Master and Slave quadrature Outputs. So I don't understand why changing to drive both Master and Slave from the Slave Outputs should have made any difference.
Regards,

Tom Kerekes
Dynomotion, Inc.

George Butty
Posts: 102
Joined: Sun Mar 22, 2020 9:36 pm

Re: 5 axis CNC Router/3d printer

Post by George Butty » Wed Feb 01, 2023 2:17 am

Hi Tom, I will load 4.35h and see what happens. Right now I am running both X1 and X2 off Ch1 and I also disabled the Master/Slave.
Just running ch1 as a straight X output. Reconfigured axis in the Init.c file. Running very nicely under these settings so far.
I also ran into a problem with KmotionCNC. I get a gcode read error pop up. This error is coming up with the files that I had no problem running before.
Can't seem to get rid of it. What would the fix be for that.
Thanks
George

Post Reply