A longstanding goal in character animation is to combine data-driven
specification of behavior with a system that can execute a similar behavior in
a physical simulation, thus enabling realistic responses to perturbations and
environmental variation. We show that well-known reinforcement learning (RL)
methods can be adapted to learn robust control policies capable of imitating a
broad range of example motion clips, while also learning complex recoveries,
adapting to changes in morphology, and accomplishing user-specified goals. Our
method handles keyframed motions, highly-dynamic actions such as
motion-captured flips and spins, and retargeted motions. By combining a
motion-imitation objective with a task objective, we can train characters that
react intelligently in interactive settings, e.g., by walking in a desired
direction or throwing a ball at a user-specified target. This approach thus
combines the convenience and motion quality of using motion clips to define the
desired style and appearance, with the flexibility and generality afforded by
RL methods and physics-based animation. We further explore a number of methods
for integrating multiple clips into the learning process to develop
multi-skilled agents capable of performing a rich repertoire of diverse skills.
We demonstrate results using multiple characters (human, Atlas robot, bipedal
dinosaur, dragon) and a large variety of skills, including locomotion,
acrobatics, and martial arts.

本研究旨在将数据驱动的行为规范与能够在物理模拟中执行类似行为的系统相结合，以实现对扰动和环境变化的逼真响应。通过将运动模仿目标与任务目标相结合，我们可以训练出能够在交互环境中智能反应的角色，例如向所需方向行走或向用户指定目标扔球。同时，本研究探讨了多种集成多个运动片段的方法，以开发出能够执行丰富多样的技能的多才多艺的代理。