Towards a Generic Bicubic Hermite Mesh Template for Cow Udders

Abstract

The shape of cow udders represents an important trait for the functionality and longevity of dairy cows, yet traditional trait definitions cannot fully capture its complexity. In this work we propose a parametric cubic Hermite (CH) based mesh to model the shape of cow udders and teats. The workflow starts from selecting a subset of nodes from the data cloud captured by a depth scanner, and constructing a CH mesh from the nodes. Using a coherent point drifting (CPD) algorithm, the nodes on the mesh are registered from one cow to their counterparts of another cow while preserving the topological coherence of the mesh. This workflow works well for the udder surface when teats are excluded. However, when teats are included in the mesh, misaligned correspondences occur due to data point occlusion and insufficient sampling points. In summary, a first parametric mesh based 3D model has been constructed for the cow udder and teat. We have examined the efficacy of the morphing algorithm, and also the issues to be solved for a statistical cow udder and teat model.