Modeling of Knee Joint in The Human Lower Extremity by Using Cam-Follower and Revolute-Translational Composite Joint
P. Eko Purwanto, Shigeki Toyama and Atsuhiko Kamijima
Tokyo University of Agriculture and Technology, 2-24-16, Nakacho, Koganei, Tokyo, 184 Japan
This paper presents a musculoskeletal model of the human lower extremity for computer simulation studies of the knee joint during movement. In this model, we developed a knee joint model by using a combination of cam-follower joint and revolute-translational composite joint. The cam-follower joint is used, where femur is the cam and tibia is the follower, to determine the reaction force as well as the reaction torque (the reaction torque cannot be calculated in the revolute joint). Furthermore the revolute-translational composite joint is used to represent the movement of the knee joint that undergoes revolute motion as well as translational motion. The estimation of muscle force is then developed from the moment of the joint that consists of moment of inertia, moment of external force, and moment resulting from the effect of gravity. In the walking motion analysis, simulation results then indicate the validity of the knee joint model and the estimation of muscle force. We therefore conclude that the use of cam-follower and revolute-translational composite joint in the knee joint model is useful to express the motion in the knee joint and to estimate force in the muscles in the lower extremity.