6650 Accuracy Errors

tom_c

Hi,
I am working with  6650's on S4C+ and am having some accuracy errors with a recently commissioned Robot.  We do surface finishing and scan with our Robots to zero and create a virtual model of our workpiece.  The curvature of our virtual model is getting distorted by the Robot: imagine a square section of a sphere where the curvature gets pinched/tightened - it should look like a piece of a sphere but ends up with elliptical looking curvature.  The Robot collides with the workpiece if it tries to go to the distorted section of the virtual model.  The distortion gets worse the further the Robot reaches out.  The other symptom I've seen is when you Jog from extended reach along a plane, the Robot drifts in the Z, turning the movement into in arc.  I have been using this scanning process for years and never encountered this with 6400's and some of our other 6650's are OK.  I have checked all the basics: Tool Definition, Basic Calibration, Arm Loads, etc.  I'm wondering if anyone else has encountered this before and if it could be a fine calibration issue or if a fine calibration could fix this. I've never seen this behavior before and am at a loss...  Any thoughts appreciated.

Regards,
Tom

tom_c

So reinstalling the system fixed this.  My coworker possibly installed the wrong settings...
On a related note, what is the difference between the 6650 and 6650 Type B?

Tom

innebandy

Comparing  with IRB6650 Type A robots, Type B robots have an enlarged gearbox on Axis 2 to improve performance.

tom_c

Thanks!