الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the present study, a comprehensive study on the application of magneto¬,logical (MR) damper in above knee prosthetic. The above-knee prosthesis has four :>r parts: the socket, the knee system, the shank and the foot-ankle system. A variety of (ets, knees, shanks, feet, and ankles are available and can be combined to produce a nhesis that best meets the needs of each individual amputee.
The motion of walking is divided into two phases for each step. These are the Ice phase and the swing phase. The stance phase takes approximately 63 % of the total e of the step. This value can vary for each subject.
The knee unit used in this study consisting of four-bar prosthetic knee chanism with MR damper operated in valve mode with a mono tube type. The modeling the artificial leg was obtained by applying Newton’s second law at the sagittal plane to d the dynamic equation of motion, by taking the moment about the instantaneous center rotation of knee mechanism.
Due to the damper’s nonlinear characteristics, its inverse dynamics model is iicult to obtain. In this study, a simplified approach has been used for the Spencer )del. The simplified inverse dynamic model has been used to calculate the input voltage, order to realize the desirable control forces obtained from the experimental works.
The input data required to the inverse dynamic model was obtained from the :perimental works by putting a surface marks on the artificial leg and perform the most lily activity to film it. After collecting the positions of the surface marks three software’s tream pix, AVI Edit, and WINanalyze were used for extracting the global position, =locity and acceleration of them at each frame. The previous experimental data were used I calculate the desired force for the MR damper during the most daily activities of the leg.
A full data for all movements were clarified in chapter four. The data obtained :om WINanalyze program were fitted to feed the inverse dynamic model which >rogrammed in SIMULINK program.
The results were summarized in chapter five and show the voltage required for he damper during most daily movements of the person who wears an artificial leg with a bur-bar knee mechanism and MR damper. Each of the voltage depends mainly on many {ariables like the values of displacement, velocity, calculated force, corresponding values )f evolutionary variable and other parameters.