Reposting with updated File

Dear Colleague    

Could you help me with my model please.

File attached. Running time is 20 minutes.

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Ball rolls on disk plate with orbiting trajectory.

Ball Dia:                                            2mm

Ball orbit trajectory radius                 2.25mm

Orbiting angle:                                  11.25 degree (0.19635 radians)

Initial step:  

step 1:  Ball is pushed down by 2.5 N

step 2:  Ball start rolling

The problem is that I don't know orbiting boundary condition 

* I defined Cylindrical coordinate system at orbit hub. R, Theta, Z

* I also defined 2 reference points;  hub orbit  centre and  ball centre.

* I interpreted the boundary  in the following way and applied it in step 2. 

       U1:       R:   (Orbit radius is not changing so this is 0)

       U2:       theta  (this is orbiting angle of ball, so 0.19635 radians)

       U3:       Z (no change so, 0)

       UR1:     rotation against R axis,   0

       UR2:     rotation against Tangent direction     0 

       UR3:     rotation against: Z axis of ball, so 0, (I am sure this, I tested) 

 The result:

The ball does NOT orbit but move in linear in Y direction in Cartesian system.

Please help me how to set up orbit boundary condition.

- Reference point etc.