Sinamics V90 - servo "stutter"?

Hello,

I am working on a school project involving three Sinamics V90 kits and one S7-1511T PLC. I am trying to build a SCARA robot.

The exact equipment codes. For the drive - 6SL3210-5FB10-4UF1 and for the servo - 1FL6034-2AF21-1AA1

I am having some issues with the rotational axis. For transmission I am using T5 belts and pulleys and the belt tension is ok, so there is no "skipping" issue.

But the motion is rather "stuttery". I will link 2 videos for you to see. The only difference between the two is the speed I am jogging the servos.

https://www.youtube.com/watch?v=slUcr38JbQ0&feature=youtu.be

https://www.youtube.com/watch?v=9AsJPSq76Hs&feature=youtu.be

The footage in the video was done using the Drive Commissioning option in TIA Portal and "Jog continuously" command.

I have tried commissioning with the V-Assistant or via the TechnologyObject - PositioningAxis and still the same "stuttery" movement.

Hi,

have you performed a One Button Tuning with the drive?

I see...the oscillation seems to be very low frequent.

Maybe I would test to more or less deactivate the position controller by entering a very small gain factor close to 0 and just move with the precontrol signal. Position controller's integral part should be 0 anyways I think. When moving just with precontrol signal you can start to adapt the speed controller settings a bit to see if changing speed controller gain and integral time brings better behavior. (making the speed controller less "aggressive" would mean to increase the integral time and reduce the gain and vice versa of course) 

If the V90 PN supports it, you should use the IRT feature of the PROFINET . see https://support.industry.siemens.com/cs/ww/en/view/109739053

Make sure, there is no setpoint ramp function active in the V90 PN