Servo tunning in CAMSOFT Pro

[Colin]

I have a Cincinnati 3 axis mill fitted with a kit from Camsoft. There are brush dc motors with Servo Dynamics Corp drivers as supplied from Camsoft. It is finally all going but is limited on the feed and traverse speeds. With too high speeds the servo drivers trip out. The worst is the Z axis which has a hydraulic counterbalance on it. I have tried running the servo tune from the Camsoft diagnostic screen but have never been able to get it to finish without faulting. Sometimes it will run for several minutes without any apparent motion. Sometimes it asks you to wait but doesn't finish. Can this autotune be made to work or is it best to go to 3rd party autotune software ? In previous conversations with Camsoft they have said that a separate computer has to be used, swapping the I/O boards and the motor control boards over so as to eliminate conflict. Is this really necessary ? It has taken so long to get to this stage, I really don't want to disturb a working machine.
Colin

[Al_The_Man]

If your motor/drive combination is not sized right for a given inertial load, then any amount of tuning is not going to make a difference.
The Z axis counterbalance should be adjusted in order to provide the same load in either direction.
But even with perfect counterbalance the Z axis inertial load has to be within the capability of the motor.
Are these the original motors, just new drives?
You could also check the current limit that the drives are set to.
Are the drives matched to the motors?
Al.

[Colin]

Thanks Al,
The motors are original, so I'm sure they would be matched. The Z axis counterbalance has been adjusted and seems to be correct. I assume that the drives are matched to the motors because that is what Camsoft supplied us. They said at the time that they had just recently retrofitted the exact same Cincinnati mill.
I could probably make better decisions if I had a graphical representation of the position/velocity response. I know that some tunning programs provide this. Do you know of one that will work with the Galoi motor control board.
Colin

[Al_The_Man]

I have only used Galil's own motor tuning s/w. Is it speed or accel/decel that it faults at?
What actually shows that it trips the drive, Over current?
Are you set up for the torque mode of operation? Did you happen to use the Tach's with the new drives?
Al.

[Karl_T]

Galil has a servo tuning package called WSDK. Cost is about $200 US for the software. Its a great package for servo tuning and analyzing your responce. I found it much more useful than the package that comes with Camsoft Pro.

There's an old thread on this NG that covers my difficulty with installation of both packages on the same computer. Read the thread, but basically, Galil will highjack your Camsoft driver if you install it after Camsoft. Install WSDK first, then camsoft, and everything works together.

Karl

[Colin]

I will get the Galili package and try that out and let you know how it goes.
Colin

[Colin]

I have purchased WSTK and after much effort, managed to get it installed. I thought that CAMSOFT would have an uninstall - but no it all has to be manually deleted and other files in the Windows directories deleted as per a previous post. After all this effort it does not work properly ! Can anyone help ?
The Auto tuning modes produce no motion at all and simply give the error message "no motor movement" (or similar wording). The "Diagnostic - dynamic test" produces a step motion and this can be tuned/changed by the PID settings, but it does not appear to be a proper step test so I don't trust this mode. It's units are in volts, but a proper step response test would be in counts or position. Furthermore the graph it produces has no units and the actual value changes with PID setting, something it should not do if it was a step test. What is this test testing ? The step response test in autotune does not produce any motor movement.

I also need help with the installation. WSTK will not work in conjuction with CAMSOFT and swapping between the 2 takes several hours so I am not keen to do it more that once. People on this UG talk about "driver conflict" but can anyone tell me the exact file that is involved and a procedure to garuntee that they will both work together.

Thanks,
Colin

[Mr.Anderson]

I think that if you get the latest version of CamSoft there is no driver conflict due to miss-matched drivers with older software.

If you still continue to use older software then somewhere on this site someone posted a list of drivers. Install the WSDK then remove the drivers that someone listed then install CamSoft, which will install the correct drivers and both programs will work just fine together. I think the whole process takes several minutes only and does not need to be done anymore.

[Karl_T]

Originally Posted by Colin I have purchased WSTK and after much effort, managed to get it installed. I thought that CAMSOFT would have an uninstall - but no it all has to be manually deleted and other files in the Windows directories deleted as per a previous post. After all this effort it does not work properly ! Can anyone help ?

My trick to uninstall Camsoft is just RENAME the AS3000 directory. (The drivers are still there) That way I don't lose any .cbk or Gcode files. But, I do agree, an un-install program should be part of any good software package these days.

Read a thread "Galil and Camsoft driver conflict" and "Galil and Camsoft driver conflict, Part 2 " that covers installing both packages. Te key is the most recent Camsoft to go with your Galil. AND Galil must be installed first.

I feel for you, I lost a LOT of time trying to get these two packages to work together.

Originally Posted by Colin The Auto tuning modes produce no motion at all and simply give the error message "no motor movement" (or similar wording). The "Diagnostic - dynamic test" produces a step motion and this can be tuned/changed by the PID settings, but it does not appear to be a proper step test so I don't trust this mode. It's units are in volts, but a proper step response test would be in counts or position. Furthermore the graph it produces has no units and the actual value changes with PID setting, something it should not do if it was a step test. What is this test testing ? The step response test in autotune does not produce any motor movement. Thanks, Colin

You've got something wrong so that the tuning isn't ready to run yet. I'm about 2000 miles away from my WSDK so bear with me (may be a step wrong here)

Use the "Getting Started" tab first. It will ask you to manually rotate shafts. After that step is right, check encoder polarity. There may be another step before you actually tune one axis. Let us know which step gives trouble.

(one gotcha to check for is limit switch polarity. The Galil default is just backward of most machines. The command CN 1,1 changes polarity)

Karl

[Colin]

Continuing the saga of tuning the servo drive parameters: All 3 axes work well on rapid but fault on feed (with feed rates over about 500-1000). The fault is unknown because Camsoft does not report that it has stopped the drive, but I suspect that it is because the drive signal (+-10V) has reached it's limit. On feed (G1), there appears to be no control of the acceleration and deceleration at the beginning and end of moves, is this true ?
The only control I can find is NEXTMOVE/SLOWDOWN, but this still introduces a "bump" at the end of a move.

What can I do to be sure that the axes will not fault at high feedrates (for instance when cutting some plastics or aluminium, or when using a high rate retract on the Z axis ?

Colin

[Al_The_Man]

You mentioned they are the original motors, What are the size of the motors? Cincinnati generally build a very hefty machine and the inertia to move some of these axis at high accelleration rates is fairly high,
Are you using the drives in the torque mode?
What is the maximum voltage of your drive power supply?
You mentioned in your first post the drives are faulting?
With the right size drives you should ideally not reach the max ±10v as you no longer have control.
Al.

[Carlo Rechi]

Mr Colin

There is servo tuning but your amp pots may need to be tuned to handle this much power. There is a pot you turn on the amp that limits the power to the motor but I no not what it is called.

I hear you say it this happens at high cutting speeds but not doing rapid. To make the cutting moves decel like the rapids you can do many things. I add a G10 to the front of any line that I want to force to slow down. You can also add commands inside the GCODE file in G1 to do this automatic and then change the decel value to what works good for you. I have also been thinking that they have a smart automatic program to sense the stress on you machine. I do not have this. It is the name smart path.

Carlo