【作者】 董罡；

【导师】 宋轶民；

【作者基本信息】 天津大学 ， 机械设计及理论， 2010， 硕士

【摘要】 本文密切结合航空航天、智能机器人等领域对纯转动并联机构的重要需求,在国家自然科学基金项目资助下,深入研究了新型空间三转动自由度并联机构3-PUS&S的设计理论与方法,内容涉及运动学分析、工作空间分析、尺度综合、虚拟样机设计及静/动态特性预估等。主要研究成果如下:1.运动学分析。根据该机构创成运动特点,采用倾斜角-扭转角法描述动平台姿态,借助螺旋理论建立机构正、逆位置分析模型与速度雅可比矩阵,并结合算例验证了上述模型的有效性。2.工作空间分析。明确该机构可达/任务工作空间的数学定义,计及移动副位移、铰链转角及连杆干涉等工程约束,逆向搜索出机构可达工作空间,并揭示了尺度参数对工作空间的影响。3.尺度综合。采用适宜的全域运动学性能评价指标,借助运动学性能图谱揭示了关键设计变量的影响程度与取值范围,并综合考虑相关的几何/工程约束,实现了机构的运动学优化设计。4.虚拟样机设计与静/动态特性预估。结合工程需求开发出虚拟样机,经运动仿真与干涉检验,验证了运动学设计理论的有效性;针对典型姿态,预估虚拟样机的静刚度与动力学特性,并揭示出关键影响因素。上述研究成果为该机构的物理样机开发奠定了坚实基础。更多还原

【Abstract】 With the aid of NSFC Project, to meet the demand for the spatial rotational mechanism used in the field of aircraft industry and intelligent robot, this thesis investigates into the design theory and method of a novel three rotational parallel mechanism which is invented by Tianjin University. The following work has been accomplished.1. Kinematic analysis. Referring to the kinematic characteristics of the three rotational parallel mechanism, the Tilt-and-Torsion angles are used to describe the orientation of the platform. Based on the screw theory, three equations involving driving parameters and pose parameters are formulated and proved by an example. And the Jacobian matrix is derived.2. Workspace analysis. The reachable and task workspace definitions of the mechanism are proposed. Then the reachable workspace is searched based on the inverse position analysis with some constrained conditions such as the actuated journey, gemel angles and linkage interference. And the relationships between dimensional parameters and workspace are studied.3. Dimensional synthesis. The influences and ranges of design variables are showed in the performance maps which describe the relationship between the global kinematic performance indexes and the design variables. Considered the geometry and engineering constraints, the kinematic optimization design is completed.4. Virtual prototype design, and the static/dynamic characteristic estimation. The virtual prototype is set up according to the demand of the engineering. Based on this model, the motion simulation and interference checking are carried out and a finite element model is proposed with the aid of ANSYS software. The key parts which affect the static and dynamic characters of the mechanism are identified by the estimation of static stiffness and modal.The above-mentioned outcomes lay a solid foundation for the development of the 3-PUS&S prototype.更多还原