Block Format Keyword This interface is Ellipsoidal Surfaces to Elements Contact. It is a penalty contact interface without damping. This interface replaces interface TYPE14, especially if the mesh is coarser than the ellipsoid size.

The secondary surface must be a set of 3-node or 4-node segments (i.e. any kind of surface; except ELLIPS and MDELLIPS surfaces). The main surface must be a MADYMO hyper-ellipsoidal surface or a Radioss hyper-ellipsoidal surface, and Interface does not allow penetrations up to half the ellipsoid.


(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
surf_IDs surf_IDm                
Stif Fric            


Field Contents SI Unit Example
inter_ID Interface identifier

(Integer, maximum 10 digits)

unit_ID unit_ID

(Integer, maximum 10 digits)

inter_title Interface title

(Character, maximum 100 characters)

surf_IDs Secondary surface identifier.


surf_IDm Main surface identifier.


Stif Stiffness factor.

No default (Real)

[ N m ]
Fric Friction coefficient.

No default (Real)



  1. Interface stiffness is a nonlinear increasing function of penetration. Stif is the interface stiffness when the element enters the hyper-ellipsoid (that is when penetration is zero).