arXiv:2603.05309cs.RO2026-03

提出无约束的连续体并联机器人静态建模方法,解决大变形下求解难题。

Constraint-Free Static Modeling of Continuum Parallel Robot

  • 通过运动学嵌入消除连接约束,转为无约束问题求解
  • 采用四阶马格努斯逼近实现端部位姿与应变的显式映射
  • 适用于大变形、大旋转场景,适合机器人控制与仿真应用

连续体并联机器人(CPR)将刚性驱动机构与多根弹性杆以闭环拓扑结合,当刚-连续体连接处施加显式运动学约束时,正向静力学求解极具挑战。传统约束方法引入额外代数变量,增加数值求解与下游控制复杂度。本文提出一种几何精确、基于构型且无约束的CPR静态模型,可在几何非线性、大变形和大旋转条件下保持有效。通过运动学嵌入消除连接约束,转化为简化无约束问题。每个弹性杆在SE(3)上离散为节点姿态,通过线性应变参数化重构单元内应变场。采用四阶马格努斯逼近,建立单元两端姿态与应变间的显式几何一致映射。电机驱动基座与末端执行器平台的刚性连接通过运动学嵌入处理。基于总势能与虚功原理,推导出可装配残差与显式牛顿切线,采用流形乘积上的黎曼牛顿迭代求解非线性平衡方程。对三伺服电机、六杆原型机的实验验证表明,模拟结果与测量值在无载运动及外部载荷情况下均具有良好一致性。

原文摘要 · Abstract (English)

Continuum parallel robots (CPR) combine rigid actuation mechanisms with multiple elastic rods in a closed-loop topology, making forward statics challenging when rigid--continuum junctions are enforced by explicit kinematic constraints. Such constraint-based formulations typically introduce additional algebraic variables and complicate both numerical solution and downstream control. This paper presents a geometric exact, configuration-based and constraint-free static model of CPR that remains valid under geometrically nonlinear, large-deformation and large-rotation conditions. Connectivity constraints are eliminated by kinematic embedding, yielding a reduced unconstrained problem. Each rod of CPR is discretized by nodal poses on SE(3), while the element-wise strain field is reconstructed through a linear strain parameterization. A fourth-order Magnus approximation yields an explicit and geometrically consistent mapping between element end poses and the strain. Rigid attachments at the motor-driven base and the end-effector platforms are handled through kinematic embeddings. Based on total potential energy and virtual work, we derive assembly-ready residuals and explicit Newton tangents, and solve the resulting nonlinear equilibrium equations using a Riemannian Newton iteration on the product manifold. Experiments on a three-servomotor, six-rod prototype validate the model by showing good agreement between simulation and measurements for both unloaded motions and externally loaded cases.

机器人建模连续体机器人非线性力学无约束求解

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。