Abstract:  Wild thick shell Mytilus coruscus in the length range of 85~110 mm was taken as the research object to explore the characteristics of shell model of Mytilus coruscus. After obtaining corresponding sample point cloud file by optical scanner, geomagic wrap software was used to process and optimize the point cloud data to obtain a 3D sample model with good quality. Matlab software was used to fit the 3D sample model to obtain the best fitting model - standard model, and the standard model was digitized to obtain the mathematical function relations of the standard model outer shell surface (W) and inner shell surface (N). By examining the errors among the digital model, standard model and sample model, it was concluded that the average error among the three models was no more than 0.06 mm. Therefore, the digital model could be used to replace the sample model to guide the design of orienting and fixing device parts of Mytilus coruscus and plan the optimal Mytilus coruscus meat stripping route, so as to lay a theoretical foundation for building a modern Mytilus coruscus processing line.

Key words: thick shell Mytilus coruscus, point cloud data, model fitting, digitization, shell surface

摘要： 以长度85~110 mm的野生厚壳贻贝作为研究对象，探究贻贝壳体模型特征。利用光学扫描仪得到相应的样本点云文件，通过geomagic wrap软件处理优化点云数据，得到质量优良的三维样本模型；利用matlab软件拟合三维样本模型，得到最佳的拟合模型¬——标准模型，并将标准模型数字化，得到标准模型壳体外曲面（W）和壳体内曲面（N）的数学函数关系式。检验数字化模型、标准模型、样本模型之间的误差，得出三者间的平均误差均不超过0.06 mm。因此，可以使用数字化贻贝模型替代样本模型来指导贻贝定向、固定装置零部件的设计，规划最佳的贝肉剥离路线，为打造现代化贻贝加工流水线提供理论基础。

关键词: 厚壳贻贝, 点云数据, 模型拟合, 数字化, 壳体曲面