Robust Biharmonic Skinning Using Geometric Fields

TL;DR

This paper presents a robust, mesh-free automatic skinning method that generates high-quality weights for both closed and open surfaces, overcoming limitations of volumetric meshing.

Contribution

It introduces a novel Lagrangian approach for skinning weights that avoids volumetric meshes and works reliably on open surfaces and triangle soups.

Findings

Produces skinning weights comparable to state-of-the-art methods

Works reliably on open surfaces and triangle soups

Eliminates issues related to volumetric tetrahedralization

Abstract

Skinning is a popular way to rig and deform characters for animation, to compute reduced-order simulations, and to define features for geometry processing. Methods built on skinning rely on weight functions that distribute the influence of each degree of freedom across the mesh. Automatic skinning methods generate these weight functions with minimal user input, usually by solving a variational problem on a mesh whose boundary is the skinned surface. This formulation necessitates tetrahedralizing the volume bounded by the surface, which brings with it meshing artifacts, the possibility of tetrahedralization failure, and the impossibility of generating weights for surfaces that are not closed. We introduce a mesh-free and robust automatic skinning method that generates high-quality skinning weights comparable to the current state of the art without volumetric meshes. Our method reliably works even on open surfaces and triangle soups where current methods fail. We achieve this through the use of a Lagrangian representation for skinning weights, which circumvents the need for finite elements while optimizing the biharmonic energy.