arXiv:2507.21957cs.RO2025-07被引 1

用微分方程方法计算机械臂自运动流形,实现全局逆运动学求解。

ODE Methods for Computing One-Dimensional Self-Motion Manifolds

  • 基于常微分方程构建新算法,直接求解一维冗余任务的自运动流形。
  • 可处理非冗余机械臂的隐含冗余,且能发现多个不连通的解集成分。
  • 适用于含移动副的系统,为实际应用提供精确全局解,适合机器人路径规划。

冗余机械臂存在无限多组关节配置可实现期望末端执行器位姿。这种逆运动学(IK)解的多样性使同时解决避障或避开关节极限等辅助任务成为可能。然而,当前主流的数值梯度迭代型IK求解器仅返回局部最优解。本文研究自运动流形(SMM),即所有满足冗余机械臂逆运动学问题的关节配置集合,本质上是全局解。聚焦于一维任务冗余情形,提出一种新型常微分方程(ODE)形式化方法,使用标准显式固定步长积分器计算SMM。还解决了如何在本无冗余的机械臂上“诱导”出一自由度冗余的问题。针对SMM可能由多个不连通成分组成的情况,提出搜索这些独立组件的方法。所提方法无需额外的逆运动学精修即可获得准确解,并扩展至包含移动副的系统——这是现有SMM文献未覆盖的领域。本文给出方法推导及多个实例,展示其工作原理与局限性。

原文摘要 · Abstract (English)

Redundant manipulators are well understood to offer infinite joint configurations for achieving a desired end-effector pose. The multiplicity of inverse kinematics (IK) solutions allows for the simultaneous solving of auxiliary tasks like avoiding joint limits or obstacles. However, the most widely used IK solvers are numerical gradient-based iterative methods that inherently return a locally optimal solution. In this work, we explore the computation of self-motion manifolds (SMMs), which represent the set of all joint configurations that solve the inverse kinematics problem for redundant manipulators. Thus, SMMs are global IK solutions for redundant manipulators. We focus on task redundancies of dimensionality 1, introducing a novel ODE formulation for computing SMMs using standard explicit fixed-step ODE integrators. We also address the challenge of ``inducing'' redundancy in otherwise non-redundant manipulators assigned to tasks naturally described by one degree of freedom less than the non-redundant manipulator. Furthermore, recognizing that SMMs can consist of multiple disconnected components, we propose methods for searching for these separate SMM components. Our formulations and algorithms compute accurate SMM solutions without requiring additional IK refinement, and we extend our methods to prismatic joint systems -- an area not covered in current SMM literature. This manuscript presents the derivation of these methods and several examples that show how the methods work and their limitations.

机器人逆运动学微分方程自运动流形

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。