I am trying to model nonholonomic constraint of Wheeled mobile robot anybody knows how ??

hi guys I am modeling a differential drive WMR (Wheeled Mobile Robot) I am done with physical modeling and joint connections and .... now I am trying to model nonholonomic constraint but I don't know how. any idea how to do it ? (there are some example in Simulink like mech_rolling_sphere but my model is in 2nd Generation simmechanic and velocity driver block doesn't exist in 2nd generation is are there any way to do model these non-holonomic constraint ???)

constraint are

1-wheels do not slip in lateral direction

2-wheel's center velocity is R*(theta-dot)

3-WMR center of gravity doesn't have velocity in lateral direction

[Rzwan Ahmed Afzal]

Hi, I hope you have found the answer to this question by now. I am also stuck in the same problem now and looking for possible solutions. Can you please share your findings?