The aim of this study is to develop an automated process for modeling average 3D human body according to body types using both NUBRS-based modeling software Rhinoceros 3D® (Rhino) and Grasshopper as an algorithm editor. First, we categorized men aged 36 to 55 years included in SizeUSA 3D data into the three body types (normal, overweight, and obese), and selected seven samples in each body type. To execute the automated process of generating an average 3D model of their lower bodies in a step-by-step manner, the following procedures were performed: (1) Determine the main reference lines on the 3D-scanned lower bodies, including six horizontal reference lines and six vertical reference lines; (2) Create horizontal and vertical line grids and intersection points (3) Generate an average 3D model in a position that corresponds to the average coordinates of the intersection points (vertex coordinates) of seven samples for each body type. A Grasshopper algorithm was formulated to automatically execute all procedures that had to be repeatedly performed. As a way to verify the average model’s size and shape, the girth measurements of the samples for each body type were averaged, and the results were compared with those of the 3D average body shape. It was found that the deviation was less than 1 cm, which indicates the validity of the 3D modeling approach applied in the present study. Each process was incorporated into commands available in the Rhino interface, and this automation allowed a number of 3D body shape modeling operations to be implemented in a significantly reduced time period.

中文翻译：

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使用 Rhino 和 Grasshopper 算法的 3D 平均人体形状建模自​​动化

本研究的目的是使用基于 NUBRS 的建模软件 Rhinoceros 3D® (Rhino) 和 Grasshopper 作为算法编辑器，开发一种根据身体类型对平均 3D 人体进行建模的自动化过程。首先，我们将 SizeUSA 3D 数据中包含的 36 至 55 岁男性分为三种体型（正常、超重和肥胖），并在每种体型中选择了七个样本。为了逐步执行生成下半身平均 3D 模型的自动化过程，执行以下程序： (1) 确定 3D 扫描下半身的主要参考线，包括六个水平参考线线和六个垂直参考线；(2) 创建水平和垂直线网格和交点 (3) 在对应于每种体型的七个样本的交点（顶点坐标）的平均坐标的位置生成平均 3D 模型。Grasshopper 算法被制定为自动执行所有必须重复执行的程序。为了验证模型的平均尺寸和形状，对每种体型的样本的周长测量值进行平均，并将结果与​​ 3D 平均体型的结果进行比较。发现偏差小于 1 cm，这表明本研究中应用的 3D 建模方法的有效性。每个进程都合并到 Rhino 界面中可用的命令中，