本篇論文提供了一個基於平衡的動作編輯方法。當給定了一段經過動作編輯後可能不平衡的人體動畫，這套方法會將不平衡的動畫轉變為平衡的動畫並盡可能保留原本動作的特性。我們分析並控制零力矩點(Zero moment point, ZMP)的軌跡以達到動態平衡。當零力矩點的軌跡跑出使用者定義的支撐區域(Supporting area)時，我們需要調整人體的關節來校正零力矩點的軌跡。本方法將平衡動作編輯看成一個受限制的狀態計算問題(Constrained state estimation problem)，我們使用非察覺型卡爾曼濾波器(Unscented Kalman Filter)去解決這個問題。在穩定的執行速度下，動畫師可以調整濾波器中的參數去微調最後產生的動畫。

This article presents a balance-based motion editing technique. Given an edited unbalanced human animation, the method converts it to a balanced one while preserving the original motion characteristics as much as possible. We achieve dynamic balance by analyzing and controlling the trajectory of the zero moment point(ZMP). If the ZMP trajectory is lying out of the user-defined supporting area, we need to adjust human joints to correct the ZMP trajectory. This technique converts the balance editing problem to a constrained state estimation problem, based on the per-frame Unscented Kalman filter framework. Animators can tune several filter parameters to adjust the final animations at a stable interactive rate.

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