PARIS: Part-level Reconstruction and Motion Analysis for Articulated
  Objects
Jiayi Liu Ali Mahdavi-Amiri Manolis Savva
We address the task of simultaneous part-level reconstruction and motion
parameter estimation for articulated objects. Given two sets of multi-view
images of an object in two static articulation states, we decouple the movable
part from the static part and reconstruct shape and appearance while predicting
the motion parameters. To tackle this problem, we present PARIS: a
self-supervised, end-to-end architecture that learns part-level implicit shape
and appearance models and optimizes motion parameters jointly without any 3D
supervision, motion, or semantic annotation. Our experiments show that our
method generalizes better across object categories, and outperforms baselines
and prior work that are given 3D point clouds as input. Our approach improves
reconstruction relative to state-of-the-art baselines with a Chamfer-L1
distance reduction of 3.94 (45.2%) for objects and 26.79 (84.5%) for parts, and
achieves 5% error rate for motion estimation across 10 object categories.
  Video summary at: https://youtu.be/tDSrROPCgUc