Abstract:

BACKGROUND: Nowadays, how to achieve the comfortableness and flexibility is the focus of the studies on artificial knee joint.
OBJECTIVE: To analyze the law of the instantaneous center of the knee during exercise and to construct a suitable evaluation function to make it better meet the requirements of the wearer comfort and natural, then get the prosthetic knee joint structural parameters.
METHODS: This paper focused on the four-bar linkage mechanism of artificial knee joint, the kinematics of mechanism model was constructed and the centrode of connecting rod was deduced on the basis of three centrosomes theorem. Regarding the comfortableness, the marking system model was established as the evaluation function; further regarding the flexibility, the multi-objective optimization model was established based on the dual optimization objective gained from the minimum total departure of actual and ideal instantaneous center in the process of bending knee and on the maximum value of evaluation function, as well as on the restriction of artificial knee joint mechanism bionics and the restriction of the double rocker linkage size.
RESULTS AND CONCLUSION: Utilizing primary target method and MATLAB program, the parameter of optimal artificial knee joint mechanism was gained. The designed four-bar mechanism can well realize the coordination of the comfortableness and flexibility.