Purpose

The purpose of this study is to investigate the shape change of breast during movement to inform product development of bras and other female wearable products.

Design/methodology/approach

Using the latest 4D body scanning technology, the authors monitored the change of seven non-circumferential breast measurements, including four linear measurements (widths, depth, etc.) and three angular measurements, across nine dynamic scans of a complete gait cycle during running. A series of statistical analysis were conducted to thoroughly investigate the measurement values in dynamic states compared with values extracted from static 3D scans.

Findings

Major findings are as follows: (1) For width-underbust, chest-depth, vertical-acromion and angle ABD, more than half of the dynamic frames presents a significant difference with the static frame. (2) Width-underbust and chest-depth measured in static can underestimate the actual values under motion. (3) vertical-acromion presents a W-shaped general trend for the nine dynamic frames with peaks observed at the keyframes (i.e. when a participant's right or left knee bends the most and rises to its highest level) and lows at the intermediate frames. (4) Angle ABD and angle BAD both present an M-shaped general trend, the exact opposite of a W-shaped trend.

Originality/value

While 3D body scanning and motion capture systems have both contributed significantly to the study of breast, 4D body scanning incorporates the advantages of both technologies and captures the 3D surface of the body during movement at each instant moment. This is one of the first studies that adopt the new technology for apparel applications.

中文翻译：

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监测从 4D 身体扫描获得的动态乳房测量值

目的

本研究的目的是调查运动过程中乳房的形状变化，为胸罩和其他女性可穿戴产品的产品开发提供信息。

设计/方法/方法

使用最新的 4D 身体扫描技术，作者监测了 7 次非圆周乳房测量值的变化，包括 4 次线性测量值（宽度、深度等）和 3 次角度测量值，跨越跑步期间完整步态周期的 9 次动态扫描。进行了一系列统计分析，以彻底调查动态状态下的测量值与静态 3D 扫描中提取的值相比。

发现

主要发现如下：（1）在胸宽、胸深、肩峰垂直和ABD角度，超过一半的动态帧与静态帧存在显着差异。(2) 静态测量的宽度-下胸围和胸深可能低估运动下的实际值。(3) 垂直肩峰在九个动态帧中呈现出 W 形的总体趋势，在关键帧处观察到峰值（即当参与者的右膝或左膝弯曲最多并上升到最高水平时），在中间帧处观察到低点。(4) 角ABD 和角BAD 均呈现M 形大趋势，与W 形趋势正好相反。

原创性/价值

虽然 3D 身体扫描和动作捕捉系统都对乳房的研究做出了重大贡献，但 4D 身体扫描结合了这两种技术的优点，并在运动过程中的每个瞬间捕捉到身体的 3D 表面。这是将新技术应用于服装应用的首批研究之一。