Generating Continual Human Motion in Diverse 3D Scenes

TL;DR

This paper presents a scene-agnostic method for synthesizing continuous, diverse human motions in 3D environments guided by sparse keypoints, enabling long, plausible motion sequences without scene-specific training.

Contribution

The method introduces a goal-centric coordinate frame approach for scene-agnostic, long-duration motion synthesis that outperforms existing path navigation techniques.

Findings

Generates long, diverse motion sequences across various scenes

Outperforms existing scene navigation methods

Works with minimal keypoint constraints

Abstract

We introduce a method to synthesize animator guided human motion across 3D scenes. Given a set of sparse (3 or 4) joint locations (such as the location of a person's hand and two feet) and a seed motion sequence in a 3D scene, our method generates a plausible motion sequence starting from the seed motion while satisfying the constraints imposed by the provided keypoints. We decompose the continual motion synthesis problem into walking along paths and transitioning in and out of the actions specified by the keypoints, which enables long generation of motions that satisfy scene constraints without explicitly incorporating scene information. Our method is trained only using scene agnostic mocap data. As a result, our approach is deployable across 3D scenes with various geometries. For achieving plausible continual motion synthesis without drift, our key contribution is to generate motion in a goal-centric canonical coordinate frame where the next immediate target is situated at the origin. Our model can generate long sequences of diverse actions such as grabbing, sitting and leaning chained together in arbitrary order, demonstrated on scenes of varying geometry: HPS, Replica, Matterport, ScanNet and scenes represented using NeRFs. Several experiments demonstrate that our method outperforms existing methods that navigate paths in 3D scenes. For more results we urge the reader to watch our supplementary video available at: https://www.youtube.com/watch?v=0wZgsdyCT4A&t=1s