Building Finite Element Model Of The Lower Extremities And Numerical Analysis Of Socks’ Comfort

Recent years, with the continuous development of science and technology， people’sconsumption concept of clothing’s comfortable requirements have already changed,comfortable clothing is more and more welcomed by consumers. Pressure on wearingclothing on the human body is an important evaluation whether the clothing is comfortable.Objectively measured pressure does not reflect the state of distribution of stress and strainunder the pressure from clothing to human skeletal as well as muscle and soft tissue. So wechoose the human lower limb as the research object, select the appropriate socks comfort ofthe human lower limb pressure as the research target, use the CMM measured modelingmethod and image modeling method to establish model of the human lower limb, choosebiomechanical model of relevant skeletal muscle and tissue to establish the constitutiverelation, establish a multi-level, multi-structure, multi-material finite element model;thenanalyze the pressure distribution on the physical model of lower limbs based on this model.What the thesis mainly researches and the conclusions are as follows:(1) Choose CT images of a18-year-old female’s legs as material, extract geometricaltomography (CT) image data of human lower limb’s skeletal muscle through the CTtomography system, then extract the boundary data, and choose this data as basis to establishmodels and analyze;(2) Use the medical software-Mimics to deal with CT image data, and finish thereconstruction of lower-limb model from point cloud file, then create a physical model basedon the principle of PRO/E’s reverse modeling: draw lines from points, surfaces from lines,bodies from surfaces, finally we can establish a precise model of human lower limb;(3)Choose biomechanical model of relevant skeletal muscle and tissue to establish theconstitutive relation,then we can establish a multi-level, multi-structure, multi-material finiteelement model;(4) In accordance with the above methods, we can do numerical analysis of the pressureon the shank. The research finds that: when giving pressure on the shank: compressive stressvalue of foreleg is higher than portion of the hind legs, it means that the forelegs’ feel is moresensitive than the hind legs, the comfortable pressure of foreleg is the key referred data topressure threshold of socks’ mouth. Select comfortable pressure threshold of leg,givingfollowing pressure to the lower leg:1.33KPa,1.73KPa,2.02KPa,2.32KPa, the range of stressof muscles and soft tissue is from317.12Pa to3265.7Pa, the range of strain is from0.00042to0.003923, the amount of deformation:(1)foreleg portion:0to0.1161mm;hind leg: from0.13369to0.58051mm. These data will provide theoretical reference to the research ofcomfortable pressure of human lower limbs, fabric structure of socks and design of elasticforce on socks’ mouth.