SSV Servo Tune variables

Has anybody used SSV to set servo tuning parameters? We have a few CNC benders we built, and I would like to have identical programs so i can keep bend settings the same between benders. I was thinking of using a binary select hard wired to a group of inputs. Based on the binary input I would set the tune parameters accordingly.

What parameters would be changed based on a Autotune set for Position Loop?

System bandwidth
system damping
loop bandwidth
integrator bandwidth

All other variables should not change if the machines are identical correct? I only expect the tunes to be different based on fit up tolerances, and age of components.

My other option would be to figure out a way to correlate the bend settings between all the benders. I have 20 part select files based off a UDT with 35 variables, 25 of which are arrays 20 long.

I have not figured out a way to copy part number 8 on bender 1, to part 8 of bender 2, when ever i make a change.

The only options I can think of are below.

Have a seperate program for each bender.
-manually enter all bend settings upon change, or new part number
-create a VB program to copy and paste values between benders
-create a master database and network all benders to access it

Have a master program
-download program to all benders whenever there is a change, or a new part number
-set servo parameters with a SSV so tunes are correct.


Does anybody have any recommendations on which direction I should go?

Thanks
Kenneth

No suggestions?

It depends on how sophisticated the model is and how much power there is.

Most motor models only use the open loop bandwidth and a gain. A problem you will have is that the model changes when moving without a load to moving with a load. You may need 2 sets of gains unless you motor has excess torque. If you know the bandwidth, gain and desired closed loop pole positions the close loop gains can be calculated.

I would have separate parameters for each bender. The mechanics may be close to the same but they are rarely exactly same.

I would have a master that downloads the parameters and bending positions to all the motors.

I have had OEM's deliver systems where the servos have been manually detuned to an acceptable common performance. Ie the servo meets the OEM's design performance specification.
To get better performance and to identify mechanical differences individual axis tuning is required.

Why does the bender making a part rely on the performance of the servo - I would have thought that it would depend on the force feedback settings so mostly product dependant?

Thank you for the replys. I would say all the mechanical are really close except for 1 axis, the bend arm. there is a noticable difference between the two benders. One bend arm I can freely swing, the second, requires a bit of force. Once I get this second one powered up i will do some tuning and see how the torque curves work. I may end up having the toolroom pull that bend arm apart and see why there is a noticeable difference between the two.

Peter, what are you picturing as a master? Have one bender the master, and send updates to the others, or have an offline PLC storing all benders recipes and update all when one is updated?