Optimal brassiere wire based on the 3D anthropometric measurements of under breast curve

It has been difficult to quantify the fit of brassiere wire to the natural nude under breast line due to the difficulty of obtaining women's nude under breast line in 3D image. The objectives of this study are firstly to design the ergonomic brassiere wire that should fit to the curve of under breast and thorax and secondly to apply the 3D measurement of human body structure to the product design and evaluation using phase shifting moiré topography. Eight brassiere wires were evaluated and key factors of comfortable wires were selected depending on the types of women's under breast those are considered as backbones of the brassiere structure. Twenty-one middle-aged women participated in the subjective wear test, and 17 volunteers of them continued to participate in the 3D image recording. 3D morphological data of the breast before and after wearing experimental brassiere was examined by phase shifting moiré topography. As results, it was found that the fitting of the global average radius of curvature of wire to that of the body line of the under breast curve was an important variable for the design of wires. Conventional shape of brassiere wire was suitable to the majority of the subjects. However, for those who have skewed under breast lines, the wire of larger global average radius of curvature along the inner part of the under breast line was rated higher in terms of wear comfort and appearance. The recommended magnitude of the torsional rigidity of the brassiere wire was about 0.015 N/mm2mm. The observation on women's under breast curve and their comfortable breast wire as discussed in this paper would provide with comfortable and stable fit for women in special needs such as soldiers, athletes and actress.