摘要
采用一种基于支链分析法的并联机构构型综合方法,综合出了具有解耦特性的2转动并联机构。首先,对2转动并联机构的结构特点进行分析,得到2转动并联机构的最简结构形式,并基于空间无约束的Kutzbach-Grübler公式对各支链的自由度组合方式进行分类,得到所有支链组合形式。其次,提出了一种并联机构初步筛选原则,并考虑球副、万向副的加工难度和成本对并联机构进行优选。最后,由于优选出的2转动并联机构存在局部自由度,对具有局部自由度的并联机构支链进行降自由度处理,得到6种解耦性好、承载能力高、精度高、结构简单的2转动并联机构。采用螺旋理论对U-RPU-UPS并联机构进行自由度分析,建立了逆运动学模型,并进行了验证。结果表明,所构建的并联机构可以实现2转动自由度的运动,并且具有很好的运动解耦特性。所综合出的2转动并联机构弥补了现有机构的不足,可作为光伏跟踪尤其是聚光光伏跟踪机构。
Based on a configuration synthesis method of parallel mechanisms of branch chain analysis, 2-rotational parallel mechanisms with decoupling characteristics were synthesized. Firstly, the structural characteristics of the 2-rotational parallel mechanisms were analyzed, and the simplest structural form of the 2-rotational parallel mechanisms was obtained. Based on the spatially unconstrained Kutzbach-Grübler formula, the combination modes of the degree of freedom of each branch chain were classified, and all branch chain combinations were obtained. Secondly, a preliminary screening principle of parallel mechanisms was proposed, and the parallel mechanisms were optimized considering the processing difficulty and cost of spherical joints and cardan joints. Then, considering that the optimized 2-rotational parallel mechanisms had passive degrees of freedom, the degrees of freedom for branch chains of parallel mechanisms with local degrees of freedom were reduced, and six kinds of 2-rotational parallel mechanisms with good decoupling, high bearing capacity, high precision and simple structure were obtained. Finally, the degrees of freedom of the U-RPU-UPS parallel mechanisms were analyzed by using the screw theory, and the inverse kinematics model was established and verified. The results show that the constructed parallel mechanisms can realize the movement of 2-rotational degrees of freedom, and have excellent motion decoupling characteristics. The synthesized 2-rotation parallel mechanism makes up for the shortcomings of the existing mechanisms, and can be used as a photovoltaic tracking mechanism, especially a concentrating photovoltaic tracking mechanism.
作者
杜小强
赵世豪
贺磊盈
DU Xiaoqiang;ZHAO Shihao;HE Leiying(Faculty of Mechanical Engineering&.Automation,Zhejiang Sci-Tech University,Hangzhou 310018,China;Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province,Zhejiang Sci-Tech University,Hangzhou 310018,China)
出处
《浙江理工大学学报（自然科学版）》
2023年第1期115-123,共9页
Journal of Zhejiang Sci-Tech University(Natural Sciences)
基金
国家自然科学基金项目(31971798)
浙江省“领雁”研发攻关计划项目(2022C02057)。
关键词
并联机构
构型综合
螺旋理论
自由度分析
转动解耦
逆运动学
parallel mechanism
configuration synthesis
screw theory
analysis of degree of freedom
rotational decoupling
inverse kinematics
