Hello All,
I'm going to do my best to describe this issue as succinctly as possible. If videos would make it easier let me know:
Robot: kr200 sp 2
Controller: krc2 4.1.6
When I jog the robot in axis specific setting all axis move well. A6-A3 move immediately and stop immediately when motion button released (not the deadman but the +/-) without bounce or play. Axis 1 and 2 both move immediately but when movement button is released they continue moving and speed down more than stop motion. This takes place over a few centimeters but is easily perceptible to the human eye. I only mention this because I don't know what "normal" behavior should be.
However, when I switch to any other jogging reference frame (robot coordinates, global coordinates, tcp) I get very significant bouncing of the end effector tool when motion is stopped. Again, I'm not releasing the deadman to stop motion, rather just letting my finger off of the +/- button. Digging a little deeper, I removed the caps from the end of all servos to examine motor motion during this "bounce". On axis 2, it is very noticeable on the exposed nut under the cap, that the nut moves back and forth after the motion button has been released.
I don't hear any audible grinding or see any bouncing while the robot is in motion. Further, when I jog the robot far from home and then run the home command it returns smoothly to its home position.
What I'm wondering is how to determine positively that this is a motor issue and not a gear issue (planetary gear not servo gear). Any suggestions for troubleshooting would be appreciated. My mechanical inkling is that a bad gear would not cause the motor to rock back like it is doing. Is this a braking issue with the motor?
Thank you.