Simulation Platform For Design Of Intelligent Prosthetic Knee Joint Based On Further Development Of ADAMS

Intelligent prosthetic knee joint with powerful functions can improve the living qualities of amputees and help them return to the society, which has great social significance. Therefore, a simulation platform for design of intelligent prosthetic knee joint with pneumatic damper has been developed in this thesis through futher development of MSC.ADAMS which is a kind of powerful simulation software, and the key problems in the process of designing this kind of prosthetic knee joint have been researched. The research work which has been done in this thesis includes the following aspects:1. A simulation platform which is adapted to design the polycentric intelligent prosthetic knee joint with pneumatic damper were established through futher development of ADAMS. The simulation platform is composed of series of menus and dialog boxes and could accomplish the functions of parameterized modeling, parameterized simulation and postprocessing.2. Design and evaluation of the polycentric prosthetic knee joint were studied. The parameters of the knee joint mechanism were obtained through optimization. In order to simulate the sound knee joint as well as possible, the objective function was determined as the instaneous center of rotation (ICR) of prosthetic knee joint approaches the ICR of sound knee joint as well as possible. The function of the prosthetic knee joint designed by optimization was evaluated through stability index and agility index. The results of the evaluation showed that the prosthetic knee joint designed by optimization is a kind of agile prosthetic knee joint which is adapted to the amputees with strong stump and can control the prosthesis well.3. The control mode during swing phase of the prosthetic knee joint with pneumatic damper was studied. The damping forces that the prosthetic knee joint needed to simulate the sound gait during swing phase at different walking speeds (fast, normal, slow) were obtained through dynamic analysis and kinematic simulation. The relations between the damping forces and the valve opening at different walking speeds were then found through building the model of the pneumatic cylinder and carrying out gas dynamic analysis and thermodynamic analysis on it, which make the intelligent control of prosthetic knee joint come true.4. The experimental prototype of the prosthetic knee joint designed in this thesis was manufactured and then the gait experiment was carried out. The gait characteristics of trans-femoral amputees’sound side and disabled side which wore his own common prosthetic knee joint and the intelligent prosthetic knee joint designed in this thesis respectively were collected by the experiment. The contrast analysis between the gait data of trans-femoral amputees’sound side and disabled side shows that the intelligent prosthestic knee joint designed in this thesis can make the amputee have better gait symmetry than his own common prosthetic knee joint in both space-time parameters and angle parameters.