IIMAS - FENOMEC
UNAM
Asymptotic modelling of tibio-femoral contact for multibody dynamic simulations of the human knee joint
Resumen:
Multibody dynamic simulations of joints require modelling the distributed internal forces generated
by articular contact. It is believed that namely dynamic and impact patterns of the contact
pressures play an important role in the development and progression of knee joint osteoarthritis.
Thus, multibody dynamic models of the knee joint capable of predicting contact
stresses would be useful for studying the mechanical aspects of this joint degenerative disease.
A multibody knee contact modelling methodology (Bei, Fregly 2004; Machado et al. 2010) should include the implementation of
an efficient mathematical model for calculating contact pressures. A number of musculoskeletal
models of the knee joint employ different forms of the elastic Winkler foundation model
(Blankevoort et al. 1991). It is known (Barber 1990) that this model is appropriate for describing the stress-deformation behavior
of thin compressible elastic coating layers, and it fails to represent contact interaction
of incompressible coatings. At the same time, it was shown (Ateshian et al. 1994) that a biphasic cartilage layer
under distributed normal forces behaves like a bonded thin incompressible elastic layer.
A new methodology for modelling tibio-femoral contact presented in this study is based on
the recently developed asymptotic model of frictionless elliptical contact interaction between
thin viscoelastic cartilage layers (Argatov, Mishuris 2011). The approach requires use of the smooth contact surface
geometry and efficient contact points detection methods. The normal contact forces are determined
analytically based on the exact solution for elliptical contact between thin viscoelastic
cartilage layers.
Informes: coloquiomym@gmail.com, o al 5622-3564.