Trajectory along the cutting path

[VaggelisKas]

Hello community,

I am trying to simulate a simple cutting technique in which
the cutting tool needs to follow a trajectory along the work piece.

The following pic illustrates my assembly and the black line is the
trajectory my tool needs to follow.

My guess is to mess with the analytical fields in the definition of the boundary condition
but every equation I have entered is not allowed by the programm to be entered in the
boundary condition edit window.

Any ideas?

Best regards.