Assembly in abaqus ace 1

[hiwiansys]

Hi All,

I have bone and implant as two parts to be assembled along their principel axis say the vertical axis ebing coaxial.I am not been able to select assembly constraing as coaxial as it is asking me to select a cylindrical or conical surface of the movable instance.neither the bone nor the implant is made up of conical or cylindrical surface.Both have complex geometry.
Please give me suitable hits to assembly both of them such that thier vertical axis lieon same line.

Thank you

Anjali

 

[brep]

Create an axis in each part, then align these axes in the assembly module.