AI 中文总结
研究针对天花板施工任务依赖重型串联机械手的问题，提出用万向节取代基座球形关节的过约束3-SPR类并联机器人Tripody，介绍其机械设计与控制堆栈，通过实验验证其性能，支持该架构用于轻型、高空、毫米级精确施工机器人。
AI 中文摘要
许多天花板施工任务仍依赖重型串联机械手，在杂乱的室内难以部署。为此，我们推出了三脚架，一种用于高空任务的轮式3自由度并联机器人，它用万向节取代了经典3-SPR形态的基座球形关节，故意对机构进行过约束。小的、分布式弹性变形吸收了由此产生的不兼容性，主要保留平移运动。该33千克系统高度从1.7米延伸到3.4米，支持连续32千克的 payload，并为天花板操作提供模块化末端执行器接口。我们详细介绍了机械设计及控制堆栈。实验表明，三脚架在平面内刚度与球形基座变体相似，但扭转刚度显著更高，闭环定位精度高，还展示了任务级天花板钻孔的可行性。这些结果支持了过约束、吸收柔顺性的3-SPR类架构作为实现轻型、高空、毫米级精确施工机器人的实用途径。
英文摘要
Many ceiling construction tasks still rely on heavy serial manipulators that are difficult to deploy in cluttered interiors, motivating lightweight, field-ready alternatives that reach ceiling height while maintaining millimeter-level accuracy and the stiffness demanded by overhead tool loads. We introduce Tripody, a wheeled 3-DoF parallel robot for high-reach tasks that replaces the base spherical joints of a classical 3-SPR (3 legs; S: base spherical joint; P: actuated prismatic joint; R: end-effector revolute joint) morphology with universal joints, intentionally overconstraining the mechanism; small, distributed elastic deflections absorb the resulting incompatibilities, preserving predominantly translational motion. The 33kg system extends from 1.7m to 3.4m in height, supports a continuous 32kg payload, and offers a modular end-effector interface for ceiling operations. We detail the mechanical design - including custom linear actuators and a kinematic-compatibility analysis - and a control stack for accurate positioning that combines SE(3) state estimation, forward kinematics, and task-space control. In experiments, Tripody exhibits similar in-plane stiffness to a spherical-base variant but substantially higher torsional stiffness - an increase of 67% at 1.7m, 196% at 2.6m, and 454% at 3.4m - while maintaining negligible cross-axis coupling. Closed-loop positioning with a total station converges below 0.6mm across the entire workspace; pure model extrapolation achieves a 95th-percentile error of 2.7mm (max 3.6mm). Finally, we demonstrate task-level ceiling-drilling feasibility in an open-loop study by drilling a 15-hole pattern with 4.5mm maximum relative hole-position error after rigid alignment. These results support overconstrained, compliance-absorbing 3-SPR-like architectures as a practical path to lightweight, high- reach, millimeter-accurate construction robots.
Comments8 pages, 11 figures, Accepted in July 2026 at IEEE Robotics and Automation Letters (RA-L)
Journal refIEEE Robotics and Automation Letters, vol. 11, no. 9, pp. 10497-10504, Jul. 2026
