This paper presents an efficient dynamics-based computer animation system for simulating and controlling the motion of articulated figures. A non-trivial extension of Featherstone's O(n) recursive forward dynamics algorithm is derived which allows enforcing one or more constraints on the animated figures. We demonstrate how the constraint force evaluation algorithm we have developed makes it possible to simulate collisions between articulated figures, to compute the results of impulsive forces, to enforce joint limits, to model closed kinematic loops, and to robustly control motion at interactive rates. Particular care has been taken to make the algorithm not only fast, but also easy to implement and use. To better illustrate how the constraint force evaluation algorithm works, we provide pseudocode for its major components. Additionally, we analyze its computational complexity and finally we present examples demonstrating how our system has been used to generate interactive, physically correct complex motion with small user effort.

中文翻译：

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动画关节的有效动态约束。

本文提出了一种有效的基于动力学的计算机动画系统，用于模拟和控制关节运动。导出了Featherstone O（n）递归前向动力学算法的非平凡扩展，该算法允许对动画人物实施一个或多个约束。我们演示了我们开发的约束力评估算法如何使仿真关节之间的碰撞，计算冲力的结果，强制关节极限，对闭合运动学环建模以及以交互速率鲁棒地控制运动成为可能。特别注意使算法不仅快速，而且易于实现和使用。为了更好地说明约束力评估算法的工作原理，我们为其主要组件提供了伪代码。另外，