ArticulateArena：一种用于关节运动学的度量
ArticulateArena: A Metric for Articulated Kinematics
- UCLA（加州大学洛杉矶分校）
- USC（南加州大学）
- University of Utah（犹他大学）
- Envora
- UCB（加州大学伯克利分校）
- Toyota Research Institute（丰田研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
针对关节物体运动评估缺乏统一度量的问题，提出表示不变的ArticulateArena度量，统一关节类型并提升至运动树，同时发布ArticulateArena-20K数据集并重新评估现有方法。
AI中文摘要：
现代方法重建或生成可用于仿真的关节物体，不仅预测其几何形状，还预测其部件如何连接以及允许的运动方式。评估几何形状是直接的，但评估预测的关节运动则不然，因为关节运动指定的是运动而非形状，并且两个运动之间没有公认的距离。更具体地说，现有协议分别对关节类型、轴方向、原点和运动极限进行评分，尽管这些参数共同描述了一个单一的物理运动，且同一运动可以用不同的参数值表示。因此，一个关节可能相对于其等效编码得到完全错误的最高分，并且若干组件误差在预测变得准确时恰好是病态或未定义的。我们提出ArticulateArena，一种表示不变的关节运动Chamfer距离对应物，它比较单自由度关节引起的运动，而不是编码它们的参数。它通过每个关节的Lie代数端点扭转的无序对来表示关节，并证明由此得到的商距离是一个度量。它统一了固定、旋转、棱柱和螺旋关节，通过紧化将连续关节纳入同一评分，并当按质量分布加权时，读作运动部件以米为单位的RMS运动。一种运动感知的树编辑距离将该度量提升到完整运动树，以与关节误差相同的运动单位对结构误差（如虚假或缺失关节）定价，并且在固定内积下，它仍然是树上的度量（直至重新标记）。伴随该度量，我们发布了ArticulateArena-20K，一个包含19,977个具有验证运动学的关节物体的新套件，并在新度量下重新评估了已发表的的重建方法。项目页面：此https URL
英文摘要：
Modern methods reconstruct or generate simulation-ready articulated objects, predicting not only their geometry but also how their parts are connected and allowed to move. Evaluating the geometry is straightforward, but evaluating the predicted articulation is not, because articulation specifies a motion rather than a shape, and there is no agreed distance between two motions. More specifically, existing protocols score joint type, axis direction, origin, and motion limits separately, although these parameters jointly describe a single physical motion, and the same motion can be written as different parameter values. As a result, a joint can score maximally wrong against an equivalent encoding of itself, and several component errors are ill-conditioned or undefined exactly where predictions become accurate. We propose ArticulateArena, a representation-invariant counterpart of Chamfer distance for articulation that compares the motions one-DOF joints induce rather than the parameters that encode them. It represents each joint by the unordered pair of its Lie-algebra endpoint twists, and we prove that the resulting quotient distance is a metric. It unifies fixed, revolute, prismatic, and helical joints, brings continuous joints into the same score through a compactification, and reads as the RMS motion of the moving part in meters when weighted by its mass distribution. A motion-aware tree edit distance lifts the metric to full kinematic trees, pricing structural errors such as spurious or missing joints in the same motion units as joint errors, and for a fixed inner product it remains a metric on trees up to relabeling. Alongside the metric we release ArticulateArena-20K, a new suite of 19,977 articulated objects with verified kinematics, and we re-evaluate published reconstruction methods on it under the new metric. Project page: https://heyumeng.com/ArticulateArena-web/
