[Farmers Machine]

Watched a video on Yaskawa site showing the autotuning on the servo drives and rapid settling on position. How would you have to set the servo tuning in camsoft using an auto tuning servo system?
Thank You
The Farmer

[Al_The_Man]

Galil has a tuning program, if that is the card you are using with Camsoft?
With Galil, the PID loop is closed back to the card, not the drive.
Al.

[spoiledbrat]

Agree with Al. I have Sigma 5 servos driving my CNC router. The autotuning features are mainly for using position mode (step and direction, or stepper mode if you are speaking galil!!!)

In torque mode, yaskawa autotuning is not available. In velocity (speed) mode, some yaskawa features are available. In Position mode, all features are available.

The claims made by my dealer were that the autotuning provided stable servo response, regardless of load/machine. This is 100% correct. You will not hear the servo's screaming and crying if you use the autotuning features.

I use position mode. I found that the response time using yaskawa autotuning alone were not good enough. I did use the tuning features to determine the load and inertia ratio for me, and ended up manually changing the gains to achieve a much more accurate, and faster response from my servos. Very pleased with the servos. If you are using galil to control these drives, good luck. I could not get position mode to work with them for my machine/application. I believe it was due to high speed 3d carving gcode clogging up the data throughput...

I did purchase the tuning program from galil (before I abandoned the galil card for the smoothstepper), but could not get it to work right. It did make terrible noises when I hit the autotune button, but not much more than that. I did try multiple settings, and use phone support from galil support along the way. I simply was not getting the right performance from the drives, so I s#!t-canned the Galil Accelera controller. Find someone knowledgable about galil and servo tuning if you are going that route.

Cheers,

Rob

[JLRB]

Rob,

I am currently building a machine using Yaskawa Sigma-V servos and a MP2300 motion controller. I am pretty new to this and this is my first foray into machine building, but I have a question for you.

One of my axis uses a direct drive servo with the load directly and rigidly coupled to the servo. My sizing software predicts a load ratio of 6.5:1 (load/motor). I can certainly use position mode. Do you see any problems with this, or am I good to go? Would you recommend I give the autotuning feature a try? Thanks.

-James

[spoiledbrat]

James,

The autotuning in the yaskawa drives is excellent. I recommend downloading the YE_Applications SigmaWin softare. With it, you can plug the drives into a laptop, and run traces (position error, etc), as well as execute the tuning functions with better control.

I did this on my machine to measure the inertia/load, and to get everything tuned. After that, I did manually adjust the gains in order to tighten up the following error. Results were amazing. No need for an occiliscope, it is built into the drives, and viewable on the SigmaWin software.

I have no experience with that controller. If that does not work for you, or if there is no front-end software available, Smoothstepper card and Mach
3 will get those things singing just fine. And fast.
Hope that helps,

Rob

[spoiledbrat]

Let me clarify that last one.

The MP2300 is indeed a great controller. Just doesnt read GCode.
It appears that you bought the mechatrolink servo drives. This means that you cannot connect a pulse/direction to the drive, and you can't use smoothstepper with it. Or mach.

However, you should check out Soft Servo Systems, Inc.: PC-Based Motion Control. I wanted to use that controller, but my drives are analog/pulsetrain (rather than mechatrolink). They have a controller that reads GCode, and is able to interface with your drives.

If anyone has a less costly solution, please chime in. I have no experience using mechatrolink stuff.

[JLRB]

Thanks for the reply, Rob.

The machine is really a purpose built machine that will only make one type of item over it's lifetime. There will be small variations from item to item, but it will essentially be doing the same thing all the time. I'd like to get more specific, but I'm kind of keeping it on the down low right now.

I have a copy of Yaskawa's Motionworks software to do the programming of the controller, and the plan is to setup and control operation from a dedicated HMI. If anyone can recommend a good related subforum for this sort of thing it would be a great help. Because the machine is not a standard xyz sort of setup I didn't make gcode programming a requirement. The mechanical construction is in progress and moving right along.

I have never used Motionworks, and have very little gcode experience, so I plan on doing a lot of learning in the near future. I have lurked in CNCZone for several years but haven't posted until now. Thanks for the friendly atmosphere.

-James