存在两条连续转轴的两转一移和两转少自由度并联机构研究

The two-rotation-and-one-translation 3-Dof (2R1T) and two-rotation 2-Dof (2R) parallel mechanisms with two continuous rotational axes, have the advantage of simple kinematic model, so it is easy to implement trajectory planning, parameter calibration and motion control, which have wide application prospects. However, structural constraints of the 2R1T and 2R parallel mechanisms with two continuous rotational axes are not investigated systematically yet, and the kinds of 2R1T and 2R mechanisms with two continuous rotational axes are very few, which restricts the development and engineering application of such mechanisms. Thus, structural constraints of the 2R1T and 2R mechanisms with two continuous rotational axes will be explored in this project, systematic theory on type synthesis of the 2R1T and 2R mechanisms with two continuous rotational axes will be established by using reciprocal screw theory. Then, the internal relation between motion decoupling of the obtained mechanisms and the two continuous rotational axes will be studied, the performances such as singularity and workspace will also be analyzed and compared. As a result, the 2R1T and 2R mechanisms with outstanding comprehensive performances would be piched out. Finally, based on the 2R1T and 2R mechanisms picked out, multi-Dof hybrid robots and 3-Dof hybrid rotating platforms will be constructed respectively, and basic theory analysis, prototype design and experimental research on the above hybrid robots and rotating platforms will be carried out, which would provide theoretical and technical basis for the design and development of the novel parallel equipment with all rotational axes being continuous.

存在两条连续转轴的两转一移三自由度（2R1T）和两转二自由度（2R）并联机构运动学模型简单，易于实现轨迹规划、参数标定和运动控制，具有非常广阔的应用前景。然而，目前尚未对存在两条连续转轴的2R1T和2R并联机构的结构约束进行系统的分析，且存在两条连续转轴的2R1T和2R并联机构类型比较少，限制了这类机构的发展与工程应用。本项目拟探索2R1T和2R并联机构存在两条连续转轴的结构约束，建立系统的关于存在两条连续转轴的2R1T和2R并联机构的型综合理论，研究综合所得机构的运动解耦性与两条连续转轴之间的内在关联，对机构奇异位形及工作空间等性能进行分析与比较，筛选出综合性能突出的存在两条连续转轴的2R1T和2R机构。基于优选出的2R1T和2R机构，分别构造多自由度混联机器人和三自由度混联转台，对其开展基础理论分析、样机设计及实验研究，为完全具有连续转轴的新型并联装备的设计及开发提供理论与技术基础。

存在两条连续转轴的两转二自由度（2R）和两转一移三自由度（2R1T）并联机构运动学模型简单，易于实现轨迹规划、参数标定和运动控制，具有非常广阔的应用前景。然而，目前尚未对存在两条连续转轴的2R1T和2R并联机构的结构约束进行系统的分析，且存在两条连续转轴的2R1T和2R并联机构类型比较少，限制了这类机构的发展与工程应用。本项目结合反螺旋理论和空间几何学理论，探索2R和2R1T并联机构存在两条连续转轴时其末端的约束线矢力在空间的布置关系，包括约束线矢力在各分支的不同分布。基于获得的分支结构约束，同时考虑各分支约束线矢力之间的几何关系，综合出合适的分支运动链。对应于每一种结构约束的各分支运动链进行合理的配置，建立系统的关于存在两条连续转轴的2R和2R1T并联机构的型综合理论，并从连续转轴角度分析2R和2R1T并联机构运动解耦性和两条连续转轴之间的内在关联。对机构支链复杂程度、受力性能等进行定性分析与比较，筛选出综合性能突出的存在两条连续转轴的2R和2R1T机构。基于优选出的2R和2R1T机构，分别构造多自由度混联机器人和三自由度混联转台构型，建立了其运动学与动力学建模，进行了尺度优化与结构优化设计，搭建了虚拟样机模型并研制了样机各1台，开展了三自由度混联转台样机的标定实验研究，标定后转台的误差得以大幅度降低。通过上述研究，本项目建立了关于存在两条连续转轴的2R和2R1T少自由并联机构的构型综合理论；揭示了2R和2R1T并联机构两转动自由度完全解耦的充分条件；建立了一套关于五自由度混联机器人与三自由度混联转台运动学与动力学分析、尺度与结构优化设计的理论方法。研究成果丰富了存在两条连续转轴的2R1T和2R并联机构构型，为完全具有连续转轴的新型并联装备的设计及开发提供了理论与技术基础。