Abstract Many three-dimensional (3D) imaging techniques, such as 3D laser scanner, stereophotography, and structured light techniques, can only capture upper half particle geometries in the camera view, and lower half particle geometries are occluded from the camera. This research aims to evaluate the accuracy of using half particle geometries to compute 3D particle shape descriptors. Computational geometry techniques are developed to compute eight commonly used particle shape descriptors automatically. Five coarse sand specimens are scanned by X-ray computed tomography and structured light to generate full 3D and half particle geometries, respectively. The convexity, diameter sphericity, and surface area sphericity computed from half particles overestimate these values computed from full 3D particles, which are corrected by statistical equations. The circularity, volume sphericity, intercept sphericity, sphere ratio sphericity, and roundness computed from half particles agreed excellently with these values computed from 3D particles.

中文翻译：

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来自半粒子几何形状的三维粒子形状特征

摘要 许多三维 (3D) 成像技术，如 3D 激光扫描仪、立体摄影和结构光技术，只能捕获相机视图中的上半粒子几何形状，而相机视图中会遮挡下半粒子几何形状。本研究旨在评估使用半粒子几何形状计算 3D 粒子形状描述符的准确性。开发了计算几何技术来自动计算八种常用的粒子形状描述符。五个粗砂样本通过 X 射线计算机断层扫描和结构光扫描，分别生成全 3D 和半粒子几何形状。从半粒子计算的凸度、直径球度和表面积球度高估了从全 3D 粒子计算的这些值，这些值由统计方程校正。