Dear FEBio Forum,

I'm trying to move from using a rigid body to using a linear elastic material to simulate bone; however, some of the ties between the cartilage-bone interface have not been successful. I've read in the forum that the tied contact in FEBio does not like curved surfaces. Unfortunately, most of the surfaces I need to tie are curved/elipsoidal. Is there a way of improving the tied contact's outcome? I have played with the penalty ranging 0.2-100 but still some of the surfaces are moving apart from oneanother. Is it a matter of playing with the penalty factor to find the optimum setting or are there more suitable options such as, welding the two surfaces (though not ideal). I am currently have the augmented lagrangian activated at value of 1 and the penalty factor at 1, also. Any help or advice is much appreciated.

Many Thanks,

Oliver