Displacement limit in electromagnetic actuator

Hello all,

I am trying to simulate the displacement of a plunger in an actuator due to the effect of the forces ( the model includes permanent magnets and a coil), so for my transient analysis I am coupling the magnetic fields physics to calculate the magnetic force and then I am using the solid mechanics to calculate the displacement due to the total forces.

There is a limited space for the plunger to move in, until it reaches the fixed boundary of the steel body (both directions). The problem I have is that after performing a time - dependent study, the plunger ignores the steel body and does not stop at the fixed boundary and keeps going at the same direction interfering with the body. I have used the spring foundation node to make it stop, but the results are not as expected. Is there any way to set the displacement limits in the model? Do you think the reason for that is maybe the wrong definition of the total force?

Another trial I am trying to do is to use the global ODEs and DAEs to define the Newton's Law of motion, but it does not seem to work correctly.

Can you please help?

Regards,
Pavlos.