Research On Multi-material Bra Wires Design By Finite Element Analysis

Lacks of bones, women’s breasts are likely to cause mastoptosis and deformations under the normal circumstance, which make ladies feel embarrassed and inconvenienced. However,wearing a suitable bra can improve this greatly. In the process, well-shaped bra wires play the important role on bearing, protecting and shaping perfect breasts. The wire will lose its shape after wearing. In the ideal state, the new form is supposed to match the under bust line. However,in the aspect of shape and structure design, designers are over relying on experience without theoretical support or verification of anthropometric information. In the aspect of material quality design, although some new materials are developed, the mismatching of wire material and wire structure leads to poorly fitting, which makes the development worthless and meaningless. Therefore, the research on shape and structure design of multi-material bra wire has important realistic meaning and theory value.Firstly, the research conducts simulation analysis on wires’ stress and distortion process in view of Finite Element Theory, solves the problem by corresponding boundary-fitted wire 3D displacements due to evaluated wire 3D forces, and then predicts and constructs 3D morphology of boundary-fitted wires. In this way, one quantifiable way of designing bra wires comes into being. Secondly, on such a basis, setting up various structures for different materials to enrich and elaborate bra wire design and development. Finally, realizing batch production. Wire 3D displacement predictive modeling simplifies design process, improves productivity and saves labor cost. Specific studies as follows:(1) Wire Mechanical Analysis Based on Bra StructureThe wire mechanical study is conducted on the condition that the human being is standing still in an upright position and analyzes the wire effects of forces in the horizontal and vertical directions. By the experimental approach, influence factor analysis of wire distortion is carried out in terms of bra straps, back wings fabric, back wings tension and bra wire material quality.(2) Wire 3D Modeling Based on Reverse EngineeringBy using Canadian high-precision handheld 3D scanner Handyscan, the research obtains point cloud data of basic bra wire and extracts 3D coordinates of wire key points with the help of Reverse Engineering. 3D solid models of basic wire are established by variable section sweep in3 D software. This effectively characterizes 3D shapes and features of the bra wire and solves the problem that tiny wire structure is difficult modeling in the reverse engineering.(3) Bra Wire Design Approach based on Finite Element AnalysisThe paper introduces Finite Element theory and method to wire designing and proposes one quantifiable designing method with segmented and discrete thinking. In other words, with the help of Finite Element Analysis software ANSYS, simulation analysis of basic bra wire is carried out and 3D force results are generated when wearing. On this basis, the boundary-fitted bra wire3 D solid model, referring to body under bust line, combines Finite Element Analysis with computer auxiliary design and manufacture, providing theoretical basis and scientific, reasonable method for wire simulation analysis, structural design shape optimization, thereby realizing bra wire customization.(4) Multi-Material Bra Wires Design and Verification Based on Finite Element MethodOn the basis of Finite Element Analysis of bra wire design, the research focuses on mechanical properties of different materials, extracts the parameters of elasticity modulus and Poisson’s ratio, designs matching material quality and structure, enriching and refining wire design and providing a strong modeling foundation for the development of new materials.(5) Predictive Model Research on 3D Displacement of Basic WireStarting with back wings tension effect on wire deformation, tensile property of back wings are tested and analyzed and mathematical model is built between back wings tension and deformation variables. By means of deformation law, experimentally, the research makes a predictive model for 3D displacement and back wings tension, so that wire 3D shape prediction can be made by body shape and tensile property of back wing. This streamlines the process,improves productivity and realizes mass production.