Study On Weakening The Energy Of Damage In The Process Of Skin Friction

There is friction and pretightening force in the contact interface between the skin and the artificial limb, while the patient is wearing a prosthetic limb. Pretightening effect of prosthetic socket will get bad and the accepting cavity tend to loosen or even slip if the friction is too small. There will be slip movement in the contact interface of skin and prosthetic socket.This will cause serious damage to the skin of the contact interface. Pretightening force increases with friction, there will cause harm to the hypoderm and serious obstacles to the blood circulation. With time goes on, it will appear poor blood circulation, skin swelling and even necrosis and cause further damage to the patients with stump. It’s not easy to make a quantitative analysis to the friction and pretightening force of the cavity contact interface between skin and artificial limb. There’s lack of scientific basis for most researchers Just by virtue of experience. And it will bring great physical pain to the patient with repeated wearing and provide a theoretical basis for rehabilitation programme of the patients.An experimental simulation is carried out on the basis of the stump of patients with normal walking condition, using tensile testing machine and UMT-Ⅲ multi-functional friction and wear testing machine combined with the independently-developed data acquisition and analysis test system in this paper. Revealing the law of energy loss and change of friction coefficient in the contact interface of skin and prosthetic prosthesis. By analyzing the experiment results of different artificial limb lining materials, the preferential range for friction of artificial limb and surface structure of socket. The main conclusions are as follows:1. The friction coefficient increases with the increase of friction force in the reciprocating friction motion between skin and prosthetic socket. The friction coefficient reaches the maximum value in the range from 15 N to 20 N then gradually decrease. Pretightening effect and the suitability of the friction and the preload force will get best by comparing and analyzing the experimental data curve.2. The energy loss in the contact surface of skin and prosthetic socket also increases with the increase of friction force, the loss of energy and skin temperature tend to be stable when the friction force change from 15 N to 20 N, so we can know that’s the best force range according to the law of friction. With the increase of friction, the energy loss and temperature of skin magnifies and this will cause serious damage to the skin of patients that should be avoided in the rehabilitation. The mapping relationship between the surface structure and roughness of the two different materials and the variation of energy loss and friction coefficient are compared and analyzed, the material pre tightening effect is good, it is more conducive to reduce the skin/prosthetic socket friction damage energy. It provides strong data support and help of the experimental results for improving the production process of artificial limb.3. The influence of surface structure and roughness on the friction behavior of different prosthetic socket was studied in the experiment. According to the comparison of the results before and after the experiment, it is concluded that the receiving cavity of the surface structure is uniform, and the energy loss and the temperature difference change smaller.