← ArchivePaper2020
Model Predictive Control with a Visuomotor System for Physics-based Character Animation
Physics-based character animation using model predictive control paired with a visuomotor perception system for reactive locomotion.
Abstract
This article presents a Model Predictive Control framework with a visuomotor system that synthesizes eye and head movements coupled with physics-based full-body motions while placing visual attention on objects of importance in the environment. As the engine of this framework, we propose a visuomotor system based on human visual perception and full-body dynamics with contacts. Relying on partial observations with uncertainty from a simulated visual sensor, an optimal control problem for this system leads to a Partially Observable Markov Decision Process, which is difficult to deal with. We approximate it as a deterministic belief Markov Decision Process for effective control. To obtain a solution for the problem efficiently, we adopt differential dynamic programming, which is a powerful scheme to find a locally optimal control policy for nonlinear system dynamics. Guided by a reference skeletal motion without any a priori gaze information, our system produces realistic eye and head movements together with full-body motions for various tasks such as catching a thrown ball, walking on stepping stones, balancing after being pushed, and avoiding moving obstacles.
How to read this
- Category
- Method: model predictive control with a visuomotor system for physics-based animation
- Contributions
- An MPC framework that synthesizes coupled eye, head, and physics-based full-body motion while attending to important objects.
- A visuomotor system based on human visual perception and full-body dynamics with contacts, using partial, uncertain observations from a simulated visual sensor.
- A tractable formulation that approximates the resulting POMDP as a deterministic belief MDP and solves it with differential dynamic programming.
- Context
- Sits in the physics-based control lineage exemplified by Peng et al.'s DeepMimic, adding a perception-driven gaze-and-body coupling rather than relying on a priori gaze data.Builds on: DeepMimic: Example-Guided Deep Reinforcement Learning of Physics-Based Character Skills
- Correctness
- Demonstrated on tasks such as catching a thrown ball, walking on stepping stones, balancing after a push, and avoiding moving obstacles; results rely on the belief-MDP approximation and DDP finding a locally optimal policy, so behavior is local and task-guided by a reference skeletal motion.
- Clarity
- Mathematically dense; a first pass conveys the perceive-then-control loop, but the POMDP approximation and DDP need a careful second pass.
- How to read it
- Focus first on how visual attention feeds the controller and what the reference motion provides; a second pass on the belief-MDP and DDP formulation is needed to follow or reproduce the control.
Builds on
Built upon by
Nothing yet.
Related work
- ControlVAE: Model-Based Learning of Generative Controllers for Physics-Based Characters 2022 / SIGGRAPH Asia
- DeepMimic: Example-Guided Deep Reinforcement Learning of Physics-Based Character Skills 2018 / SIGGRAPH
- UniCon: Universal Neural Controller for Physics-Based Character Motion 2020 / arXiv
- PDP: Physics-Based Character Animation via Diffusion Policy 2024 / SIGGRAPH Asia
Keywords
This page summarises the entry and links to its original source. The archive never hosts or redistributes the publication itself.Show it in the full archive list →