In a structural analysis by finite elements, it is sometimes necessary to model the kinematic connections between two bodies in a very fine manner in order to appropriately represent the effort transfer. AROBAS Technologies holds a strong expertise in this type of modeling through the acute physical sense and mastery of specific components (connectors, equations, rigid links, ...). The typical example is the ball bearings model created by AROBAS Technologies that takes into account (for lower calculation costs) the stiffness of the link bearings by integrating the number of rolling elements, their preload, their interval, and their contact stiffness (Hertz Theory). This model can not only be integrated into nonlinear static calculations, but also finds its place in dynamic models subject to modal analysis.