Anilam/ supermax Frankenstein project using Dynomotion Kflop and Kanalog boards.

[TremFab]

I FORGOT ABOUT ENCODER COUNTS!!!! I set up a travel indicator and moved in half inch increments on all three axis and tried multiple times in each direction and encoder counts:distance is really consistent on the x and y axis but the z axis is only accurate to within about 20 counts. moving a half inch for the x and y axis gives me a consistent count of 1270 or 2540 counts/inch. and the z axis gave me numbers ranging from 2536 counts/inch to 2494 counts/inch that gives me approximately .0004" per count and the count inconsistency gives me an error of about .018 on my z depth. considering I will be using this machine mostly for hole patterns and single level tool paths this error doesn't really bother me.

doing some quick math using my x axis i see about 200 IPM

3000 counts in about .3 seconds
3000 counts is about 1.181 inches x 3 = 3.543 inches/sec
3.543 X 60 = 212 Inches/minute

Any thoughts, feelings, frustrations, or concerns?
-WT

[TomKerekes]

Hi WT,

Very good. The second plot is not saturating. I think it would be better to slow down a bit and use higher gain for better accuracy. Reduce Velocity to 9000 counts/sec. That would be:

9000/2540 = 3.54 inches/sec = 213ipm (same as your calculations).

Your acceleration is still way too high also. Reduce to 50,000. So in summary:

Velocity = 9000
Acceleration = 50000
Jerk=1000000

We should now focus on tuning for accuracy. Right now the following errors are almost 1/4 inch (500 counts) at max speed. You may not care much about that for a drilling application but I'm sure we can do much better. Put the P gain up to 5 or higher if you can. Then add some I gain. Start with 0.0001. Then increase until things go unstable. Then reduce by a factor of 2.

You will find that I gain will increase the accuracy a lot as it forces the average error to be zero. With P Gain alone the system can get "stuck" with a small error that is not enough to cause the motor to move. But I gain keeps summing/accumulating the small error over and over applying more and more output until eventually the motor will move.

If you plot position error it will be easier to see how well we are doing.

Regards

[TremFab]

P10 I .0001 just for a "control sample so I can compare notes.


P10 I .001


P10 I .02 for "scientific purposes"

Settled on this:



the other graph looked a little wonky to me so i backed off the P to 7 these were the results for the position graphs:

P7 I .001

this seemed the best average between the two graphs. I hope I'm not too far off base.
WT

[TomKerekes]

Hi WT,

Those look fairly good although still a bit sluggish. If the performance meets your requirements then they are fine. You might have tried some some I Gain values between 0.02 and 0.0017. That is a big change. Did you mean to test 0.002?

I think plot #5 tells a lot about your system's characteristics. Looking at the period from 2-3 seconds you can see how the position sticks and breaks free moving a few counts taking about 1 second for the Integrator to drive the error from about 20 counts (~0.008 inch) to about 1 count (0.0004 inches) over a period of ~1 second.

I suggest we assume that is good enough for now and move on. You can always return to do more tuning.

I would suggest setting the Max Following Error on the Config Screen to 250 counts so that if the system hits something or goes unstable for any reason it will Disable.

The next step is to convert all the parameters into a C Program to initialize everything. This can be accomplished very easily with the following:

#1 Using KMotion's C Program Screen select Thread #1
#2 Open the example C program called Init3Analog.c
#3 On the Config/Flash Screen push "Export All to Open C Program"
#4 Depress "OK" to a message indicating Axis Channels 0,1,2 will be Updated.
#5 On the C Program Screen push "Save As" and supply a unique name

You are now ready to Assign this program to a button in KMotionCNC

#1 Run KMotionCNC
#2 Select the Tool Setup
#3 Select the "User Buttons" Tab
#4 Select "Execute Prog" mode for the First Button and change its label to "INIT"
#5 Enter Thread=1 Var=0 and File as the one you created above

Let's also set up the System Resolution and such on the Trajectory Planner Tab

I think all your resolutions are 2540 counts/inch

Convert Velocities and Accelerations that you found in KMotion to inches by dividing buy 2540

Velocity 9000/2540 = 3.54 in/s
Acceleration 50000/2540 = 20 in/sec2

Check that your Jog Speeds and Step Increments are set to your desired values

Select "OK" to exit the Tool Setup.

You should now be able to push the "INIT" button to initialize your system

I believe Jog Buttons and basic GCode should function.

Let me know how far you get.

Regards

[TremFab]

The next step is to convert all the parameters into a C Program to initialize everything. This can be accomplished very easily with the following:

#1 Using KMotion's C Program Screen select Thread #1
#2 Open the example C program called Init3Analog.c
#3 On the Config/Flash Screen push "Export All to Open C Program"
#4 Depress "OK" to a message indicating Axis Channels 0,1,2 will be Updated.
#5 On the C Program Screen push "Save As" and supply a unique name

#1 Got it!
#2 Got it!
#3
I don't have that button. Will "copy to C clipboard" and pasting the individual channels in place of the sample c program in their respective places suffice? I understand G code, I know they are not at all that similar, but its pretty simple to look at it and see what all these lines are doing and calling for now that I have been playing with all of the parameters for a couple weeks now. In the meantime I will try this and see if it works.

Then from there it APPEARS to be cut and dry.

[TremFab]

I'm a tinkerer, answering my own question through a theory that c programming is done similarly to G and M code. by giving specific command with a given magnitude and speed. C code being just a list of parameters that constrain how, In this case, a machine behaves by giving it limits. more or less what looks like, when simplified, if/then statements. Only one parameter per line, and the programmer(s) of the source code was (were) even brilliant enough to construct all of the terms in the c code to be intuitive to the human reader so that they can see where to go to change a small error. what bothers me is that the tuning was very much the hardest part so far. Not the programming. Either that, or Tom is just a genius at making people capable of doing things they don't understand.

So, I have Kmotion CNC running a few of the sample programs and I have even edited in some changes to see if things would work as planned. THEY DID!!!! EXCITING STUFF!!!
all of the axis are moving in almost perfect precision. (after I figured out my machine was in inches and the DRO in kmotion cnc was in sillymeters.) I'd like to figure out how to reduce the servo movement when the machine isn't moving though, its a bit annoying. its moving less than a .001" so I'm not really worried about it tooooo much.

My Z axis is moving in the opposite trajectory than I want it to, I'll keep playing with it but how do you reverse the direction?

The kmotion cnc works but the programming is a bit different and I'm not sure if my cam package has a post for it. How can I make this machine play nicely with MACH 3? i have been reading pouring through the online help but it gets to the c programming part I get lost again. I can find the files but i dont know what to do with them when i find them.

[TomKerekes]

Hi WT,

Great progress. Its a pleasure to work with someone who can explain what they are thinking, follow instructions carefully, answer questions, explain what they did, what happened, and not be afraid to reveal they don't know something.

I don't have that button. Will "copy to C clipboard" and pasting the individual channels in place of the sample c program in their respective places suffice? I understand G code, I know they are not at all that similar, but its pretty simple to look at it and see what all these lines are doing and calling for now that I have been playing with all of the parameters for a couple weeks now. In the meantime I will try this and see if it works.

You must be running an older Version here is our current Configuration Screen. The C Code->Clip Board will work just as well. It just takes more steps.

after I figured out my machine was in inches and the DRO in kmotion cnc was in sillymeters

I assume you realize you can display inches or mm.

I'd like to figure out how to reduce the servo movement when the machine isn't moving though, its a bit annoying. its moving less than a .001" so I'm not really worried about it tooooo much.

The first thing to try is the Dead Band Range/Gain. This allows the system to treat small errors less aggressively. Or to ignore them entirely. A Deadband Gain of 0 is like telling the servo to stop trying to make corrections when it is within the Dead Band Range.

My Z axis is moving in the opposite trajectory than I want it to, I'll keep playing with it but how do you reverse the direction?

See faqs

The kmotion cnc works but the programming is a bit different and I'm not sure if my cam package has a post for it. How can I make this machine play nicely with MACH 3?

The same Initialization file can be used to Configure KFLOP within Mach3 so there isn't much to do. See Here

Next steps might be to add Limits, Homing, and Spindle Control.

Regards
TK

[TremFab]

started getting random sporatic and unprompted jumps in my x axis. spent three hours trying to figure it all out. im going to completely wipe the slate clean and start over tomorrow. Now that I have a better idea what im doing i can just go for it!

[TomKerekes]

Hi WT,

There are some simple observations in cases like this that can help narrow down the problem. The main one is if the encoder tracks position properly. Move back to the same position before and after a "jump" and check if the position reading repeats.

Regards

[TremFab]

I'm not getting any positive results. I'm thinking possibly that I goofed up when I set a parameter and it has been flashed to the kflop. In despiration I just started making rash decisions and got inpatient at the end of a long day of almost getting things to work then moving in the wrong direction. I really don't believe that its a hardware issue, moreover a user error. now I "recieve the OPPORITUNITY" to hammer on this project until I get it done because I need this mill basically for all of the projects that I currently have in the shop. (yes I could do it the hard way, but id waste time and money doing it that way. Id rather spend that time and money fixing the machine and just have it work right and save the headache of doing things the hard way.) Yesterday I had CNC control of the machine and in what seemed to be correct trajectories and magnitudes, then I tried to link it into Mach 3 and ran into issues. Sometimes you just need a bigger hammer...

is there a way to reset the kflop and kanalog to default settings or wipe it clean as it were?

I think cutting my line and retying is going to be a better/faster option over untangling the fishing line.

[TremFab]

having a steady drift on all three axis, they aren't servo-ing
Here is what I know:
1) Re-installed all Kmotion software.

2) I have entered all three axis with the same parameters (they all at least somewhat worked respectably well before in each axis.) The only differences would be Channel (axis) input/output numbers are 0-7 1-6 2-5 respective to each axis. all others are "no input/no output" and respective channels are all set to different channels than those listed above.

3) I compiled downloaded and ran the basic starter motor configuration c file to get rid of whatever was in the K boards. (good or bad idea I don't know, but at least I know what is on there now.)

4) All of the encoders seem to be working fine still. I checked them with an indicator. They still move.

5) the 0,1,and 2 channels are all "enabled" in step response

6) when turn on the servos they don't even jump when I hit "move" in step response.

With these symptoms do you see anything that I missed and made my own life difficult?
does anything in these statements seem odd or stick out?
was I supposed to flash "new" onto the K boards?

[TomKerekes]

Hi WT,

I don't know what you mean by "basic starter motor configuration c file". But that is probably not a good idea. Cycle power on KFLOP and start from its default configuration.

I see you are running KMotionCNC. Do not do that until after you get your system working in KMotionCNC.

Work with one motor at a time and one step at a time.

Basically go back to post #1 and verify your hardware and settings. Can you move the motor with DAC commands?

Regards

[TremFab]

I did all the hardware checks, and everything checks out, but I cant get the servos to stay put. DAC commands aren't working at all and I have roughly 10 seconds to get anything accomplished. I tried "DAC0=0" and it wouldn't stop moving. also tried "DAC0=1000" (did this with all three axis) didn't have any change in speed. Is there any way to do a hard reset on the boards to make them go to default settings? or a "default" set of programs to run and flash to memory that the boards come with?



UPDATE: after more mindless fiddling, turned off the power supply for about 10 seconds turned it back on and the y axis started working again. So I turned off everything for a while and came back to it and all three axis were working again. Don't know how or why. I'd Rather be lucky than good any day. so moving on to where I was on two days ago...

[TomKerekes]

Hi WT,

Step #1 is to check if DAC0 works. If that fails stop. There is no point in skipping a failing step and going forward.

We don't recommend Flashing Configurations or programs to KFLOP as it isn't necessary for your type of system. If you think you might have Flashed something to KFLOP by mistake you can restore KFLOP to all defaults using the Config/Flash New Version Button.

So in summary:

#1 Flash New Version to KFLOP
#2 Cycle Power On KFLOP
#3 Check if the Enabled LED on Kanalog is on
#4 Enter DAC0=200 on the Console Screen

If not check if the Voltage on the DAC0 Output is ~ 1V.

HTH
Regards


Does the motor move?

[TremFab]

OK.... not really sure why but things started making sense and pulling together, I'm so close I can taste it! here is my tiny little problem...

E stop button on the control screen won't "stick" (the digital one on the screen) it resets for a second or two.In that time I can jog or zero the dro buttons, but I literally only have about one or two seconds. I'm not hitting any limits because they are hard wired into the servo drives to shut them off. everything seems to be functioning correctly other than that... So this leads me to believe that I have all the programs in order but there is just a couple parameters that are arguing with each other. It Doesn't do this in kmotion cnc. that program seems to be working fine. I think this is where I was a couple days ago but couldnt figure out that it was the E stop. GRRRRRRR


I hope this is the last thing everything looks so close. I think this is it!!!

[TomKerekes]

Hi WT,

What do you have the Mach3 EStop input configured as?

Regards

[TremFab]

that is the only input that is enabled right now. key 27 is the escape key.

[TremFab]

ITS ALIIIIIIVE!!!!!!!!!! I spent another 2 hours scouring the interwebz and found a guy with a similar problem on Rockcliff machine inc forum. ( I hope that isn't a four letter word here) anyways it was as simple as leaving the e stop enabled and changing the port and pin for the e stop input to zeros. basically telling the computer "yes there is an e stop, but it doesn't have anything to do with you. So don't look for it" I hate how the simplest things often prove to be the most difficult to figure out because you are so intent of fixing a problem that you overlook or ignore entirely the small stuff! Even worse, the things that you thought were going to be easy turned out to be difficult and the things that you thought were going to be impossible turn out to be the easiest part.I think Ill be buying another K motion setup for my next project! CNC Router!!!!!!! now that I have a fairly firm grasp on how to make them work.


THANK YOU SOOOOOOOO MUCH FOR ALL YOUR HELP!!! words cant express how ecstatic I am!!! I was literally yelling in the shop, I was so excited! I thought my computer locked up when the reset button turned green and STAYED green. Thanks a million!

[TomKerekes]

Yahoo!! Thanks for your patience. (I was just typing that you can't use IO Bit 10 as an Estop input as that is being used for the KFLOP-Kanalog communication).

Good luck

[ricochet]

Hi Tom, This post of Q&A with WT is by far the most informative material I have found for getting started and completing a project with Kflop / Kanalog and Dynomotion.

Thanks for all you do!

....ricochet