一种新型非对称五自由度混联机器人的尺度综合

提出一种新型非对称五自由度混联机器人，由三自由度1T2R位置型并联机构和二自由度A/C转头串接组成。为保证机器人具有近似面对称的性能，围绕其中的并联机构开展尺度综合研究。通过定义并联机构的参考位形，提出一种凝练独立尺度参数的方法，并定义出可评价工作空间、运动/力传递特性及其面对称程度的运动学性能指标。在此基础上，将机构尺度综合问题归结为一类有约束多目标优化问题，并采用范数理想点法，得到一组可使机构兼具优良的运动/力传递特性及大作业空间/机构占地比的尺度参数，同时运动/力传递特性在全域内具有近似面对称乃至轴对称分布。在相同尺度参数下与Exechon和TriMule机器人的对比分析表明，该机器人具有与二者近似的全域运动学性能。

Dimensional Synthesis of a Novel Asymmetric 5-DOF Hybrid Robot

A novel asymmetric 5-DOF hybrid robot was proposed, which composed of a 3-DOF 1T2R parallel mechanism and a 2-DOF A/C wrist. In order to achieve a nearly plane symmetric kinematic performance, the dimensional synthesis approach of the 3-DOF parallel mechanism was subsequently investigated. Firstly an approach to extract the dimensional parameters was presented by the definition of the reference configuration. Then a set of kinematic indices were proposed for evaluating the workspace, motion/force transmissibility and level of plane symmetry. Finally the optimal dimensional synthesis was theoretically formulated as a multi-objective optimization problem with constrains, leading to a set of homogeneous dimensionless parameters that were enable to achieve both of large ratio of workspace volume over footprint and good motion/force transmissibility with a nearly plane symmetric and even axisymmetric distribution. A comparison study shows the novel hybrid robot has a very similar global kinematic performance to that of the Exechon and TriMule provided that they both have same dimensions.