Construction Of Pressure Attenuation Prediction Model And Development Of Adjustment System For Seamless Pressure Garment

Pressure therapy is an important method commonly used in the clinical rehabilitation.It is a treatment method that exerts pressure to human body surface by pressure garment or pressure tube to treat varicose veins of lower limb,inhibit growth of burn scar,relieve limb swelling.Pressure therapy is commonly used in the treatment of hypertrophic scars after burns.The pressure exerted by the pressure garment on treatment sites is the key to pressure therapy in the treatment.Pressure therapy is a long-term treatment method,which is still difficult to maintain continuous pressure exerted treatment site the during long-term intervention.The most important characteristics of the pressure garment made of elastic fabric are with the elasticity and resilience,and this ensures that the pressure garment could exert continuous pressure on human body.However,the pressure of elastic fabric in the stretched state changes with time,and the interface pressure between the skin and the garment will continue to decrease over time,which affects the therapeutic effect of pressure therapy.Correct and active constant pressure treatment is the guarantee to improve the therapeutic effect of pressure garment therapy.The current clinical solution of this problem is to replace the pressure garment in time after the pressure drops.This method not only cannot guarantee continuous and stable pressure delivery,but also cause waste.Therefore,in order to improve the clinical treatment effect of pressure therapy and ensure the effectiveness and durability of the pressure garment in the long-term pressure treatment process,it is urgent to carry on in-depth research on the problem of maintaining continuous and uniform pressure delivery of the pressure garment exerted on the treatment site.There were 8 seamless knitted fabrics with spandex/nylon yarn as ground yarn and nylon as plating yarn taken as the research object in this paper.Firstly,in order to study the relationship between the mechanical properties of seamless knitted fabrics and garment pressure,the tensile properties of samples were tested,and the elastic modulus and tension of samples were calculated.The regression equation of fabric elongation rate and its tension was established by the linear regression analysis of fabric tension and elongation rate.Secondly,based on Laplace’s law and reduction coefficient method,there were cylinder models selected with different circumferences of the human body in the experimental design,and compression tubes with 20% reduction coefficient were made,and the clothing pressure test was carried on.The difference between measured pressure values of compression tubes and the predicted pressure values by applying Laplace’s law was compared,so as to verify the accuracy and applicability of Laplace’s law.Thirdly,there were 4 fabrics with larger elastic modulus as the research object,and7 compression tubes were made with different sizes,including reduction factors of 10%,15%,20%,25%,30%,35%,40%.and the influence of time variables on clothing pressure was considered,put compression tubes on two different cylinder models in sequence,and measured the pressure on them according to the time interval.The non-linear negative exponential function was used to describe the variation regularity of the pressure value exerted by the compression tube to the cylinder model with time,and the mathematical relationship between pressure value,reduction coefficient and time was established with the second-order polynomial surface equation.Finally,based on this model relationship,the garment pressure adjustment mechanism system was developed by Java and Python programming,which was used to predict the change trend of garment pressure and adjust the size of the pressure garment.It was found that there was a positive linear relationship between the coursewise tension of the sample and the elongation,and the average degree of fitting of the regression equation reached 99.8%.By analyzing the relationship between pressure of compression tube and reduction coefficient,it was shown that the clothing pressure and reduction coefficient had a linear increasing trend.The Kolmogorov-Smirnov test and the paired samples T test were performed on the measured pressure and the predicted pressure of compression tubes with 20% reduction,including 4 different cylinder models and 8 samples.There was no statistical difference between the measured pressure value and the pressure value predicted by Laplace’s law in the cylinder models of girth 1 and 2,indicating that Laplace’s law could better predict the pressure exerted by the fabric on the body with a smaller circumference.The nonlinear negative exponential equation to fit the pressure value exerted by the compression tube to the cylinder model varies with time in the same reduction coefficient was finished,and the average fitting error was 0.0133875.The mathematical model between pressure value,reduction coefficient and time was established and the average R2 of models was 0.993.The model could predict the pressure change trend of the pressure garment during the use of different sizes of pressure clothing,or calculate the size of the pressure garment according to the pressure required by the pressure clothing and the time of use.Based on Java and Python programming,a pressure garment pressure adjustment mechanism system was developed,which can calculate the consumer’s corresponding garment garment size information according to the consumer’s treatment pressure value requirements.