MaskedMimic：通過遮罩運動修補實現統一的基於物理的角色控制

MaskedMimic: Unified Physics-Based Character Control Through Masked Motion Inpainting

September 22, 2024

作者: Chen Tessler, Yunrong Guo, Ofir Nabati, Gal Chechik, Xue Bin Peng

cs.AI

摘要

打造一個單一且多用途的基於物理的控制器，能夠賦予互動角色生命，跨越各種場景的廣泛範疇，代表著角色動畫領域中一個令人興奮的前沿。理想的控制器應該支持多樣的控制模式，例如稀疏的目標關鍵影格、文字指令和場景信息。雖然先前的研究提出了基於物理模擬、場景感知的控制模型，這些系統主要專注於開發每個專精於狹窄任務和控制模式的控制器。本研究提出了一種新方法MaskedMimic，將基於物理的角色控制定義為一個通用運動修補問題。我們的關鍵見解是訓練一個統一的模型，從部分（遮罩）運動描述中合成動作，例如遮罩關鍵影格、物件、文字描述或任何組合。通過利用運動追踪數據並設計一種可擴展的訓練方法，能夠有效利用多樣的運動描述來生成連貫的動畫。通過這個過程，我們的方法學習了一個基於物理的控制器，提供直觀的控制界面，無需為所有感興趣的行為進行繁瑣的獎勵工程。所得的控制器支持廣泛的控制模式，並實現不同任務之間的無縫過渡。通過運動修補將角色控制統一起來，MaskedMimic創造了多才多藝的虛擬角色。這些角色可以動態適應複雜場景，根據需求組合不同的動作，實現更具互動性和身臨其境的體驗。

English

Crafting a single, versatile physics-based controller that can breathe life into interactive characters across a wide spectrum of scenarios represents an exciting frontier in character animation. An ideal controller should support diverse control modalities, such as sparse target keyframes, text instructions, and scene information. While previous works have proposed physically simulated, scene-aware control models, these systems have predominantly focused on developing controllers that each specializes in a narrow set of tasks and control modalities. This work presents MaskedMimic, a novel approach that formulates physics-based character control as a general motion inpainting problem. Our key insight is to train a single unified model to synthesize motions from partial (masked) motion descriptions, such as masked keyframes, objects, text descriptions, or any combination thereof. This is achieved by leveraging motion tracking data and designing a scalable training method that can effectively utilize diverse motion descriptions to produce coherent animations. Through this process, our approach learns a physics-based controller that provides an intuitive control interface without requiring tedious reward engineering for all behaviors of interest. The resulting controller supports a wide range of control modalities and enables seamless transitions between disparate tasks. By unifying character control through motion inpainting, MaskedMimic creates versatile virtual characters. These characters can dynamically adapt to complex scenes and compose diverse motions on demand, enabling more interactive and immersive experiences.