Mesh2Animation: Unsupervised Animating for Quadruped 3D Objects

Animating quadruped 3D objects, such as chairs and tables, typically involves three steps in the traditional computer graphics pipeline: Rigging, Skinning, and Retargeting. Commonly, prevailing methods for each specific step are conceived in isolation. For rigging and skinning steps, optimization-based methods are typically used, but these approaches tend to be slow and susceptible to variations in 3D mesh surfaces. For the retargeting step, the obtained results often fall short of expectations, especially when dealing with dissimilar source and target skeletons, leading to issues like joint twisting. The devised procedure is also time-intensive, resulting in a complex final pipeline. To this end, we present a unified framework, termed Mesh2Animation, providing an end-to-end solution to these challenges. In Mesh2Animation, a learning-based method is proposed for quadruped 3D skeleton estimation. We introduce both skeleton-level and mesh-level loss, allowing the rigging, skinning, and retargeting steps to be optimized simultaneously. Specifically, a general predicted estimation from the rigging step initializes the skeleton, making the skinning step faster and more accurate, which in turn leads to better results in the retargeting step. Finally, the rigging, skinning and retargeting processes are optimized simultaneously under static and temporal constraints. Additionally, we can construct a novel animating dataset termed ShapeNet2Animation (SN2Animation) based on the proposed method, which shows potential application for pose transfer. Qualitative and quantitative results on SN2Animation, ShapeNet, Object3D and ModelNet10 datasets for animation demonstrate that our method achieves competitive performance and shows promising generalization ability on quadruped 3D objects. Our project is available athttps://sites.google.com/view/mesh2animation.