基于三维点云的小麦叶片曲面参数化重建方法  

Parametric Reconstruction Method of Wheat Leaf Curved Surface Based on Three-Dimensional Point Cloud

作　　者：朱顺尧 瞿宏俊 夏倩 郭维 郭亚 ZHU Shunyao;QU Hongjun;XIA Qian;GUO Wei;GUO Ya(Key Laboratory of Advanced Process Control for Light Industry,Ministry of Education,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学物联网工程学院,“轻工过程先进控制”教育部重点实验室,江苏无锡214122

出　　处：《智慧农业(中英文)》2025年第1期85-96,共12页Smart Agriculture

基　　金：国家自然科学基金项目(51961125102,31771680)。

摘　　要：[目的/意义]植物叶形是植物结构形状的重要组成部分。叶片三维结构模型的建立有助于模拟和分析植物生长。针对三维结构表示与数学模型参数的互操作性,本研究提出了一套参数驱动的具有互操作性的小麦叶片点云反演模型。[方法]利用参数化建模技术,建立具有7个特征参数的小麦叶片参数化曲面模型。基于小麦叶片三维点云对模型参数进行反演估计,实现叶片曲面的逆向参数化构建。为验证该方法可靠性,使用Chamfer距离评估重建点云与原点云间差异度。[结果和讨论]该模型能有效地重建小麦叶片,对于实测数据基于点云的参数化重建结果的平均偏差约为1.2 mm,具有较高的精度。重构模型与点云具有互操作性,可以灵活调整模型参数,生成形状相近的叶簇。反演参数具有较高的可解释性,可用于点云时间序列的一致、连续地估计。[结论]该模型对叶片的一些细节特征进行了适度的简化,只需要少量的参数就可以还原叶片的几何形状。该方法不仅简单、直接、高效,而且得到的参数几何意义更明确,具有可编辑性和可解释性,对小麦叶片的模拟分析和数字孪生具有重要的应用价值。[Objective]Plant leaf shape is an important part of plant architectural model.Establishment of a three-dimensional structural model of leaves may assist simulating and analyzing plant growth.However,existing leaf modeling approaches lack interpretability,invertibility,and operability,which limit the estimation of model parameters,the simulation of leaf shape,the analysis and interpretation of leaf physiology and growth state,and model reusage.Aiming at the interoperability between three-dimensional structure representation and mathematical model parameters,this study paid attention to three aspects in wheat leaf shape parametric reconstruction:(1)parameter-driven model structure,(2)model parameter inversion,and(3)parameter dynamic mapping during growth.Based on this,a set of parameter-driven and point cloud inversion model for wheat leaf interoperability was proposed in this study.[Methods]A parametric surface model of a wheat leaf with seven characteristic parameters by using parametric modeling technology was built,and the forward parametric construction of the wheat leaf structure was realized.Three parameters,maximum leaf width,leaf length,and leaf shape factor,were used to describe the basic shape of the blade on the leaf plane.On this basis,two parameters,namely the angle between stems and leaves and the curvature degree,were introduced to describe the bending characteristics of the main vein of the blade in the three-dimensional space.Two parameters,namely the twist angle around the axis and the twist deviation angle around the axis,were introduced to represent the twisted structure of the leaf blade along the vein.The reverse parameter estimation module was built according to the surface model.The point cloud was divided by the uniform segmentation method along the Y-axis,and the veins were fit by a least squares regression method.Then,the point cloud was re-segmented according to the fit vein curve.Subsequently,the rotation angle was precisely determined through the segment-wise transform estimation meth

关 键 词：小麦叶片 曲面参数化 三维点云 点云重建 参数反演 数字孪生 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]