四自由度并联工作台虚拟设计与仿真

发布时间：2018-08-19 13:24

【摘要】：并联机床是空间多环机构在机床制造业上的创造性应用,是并联机构与现代机床技术相结合的产物,它可与传统数控机床形成很强的互补。并联机床虽然具有结构简单、刚度大、质量轻、响应速度快等优点,但是随着并联机构理论技术的发展,其制造成本高、工作空间与外形尺寸比不合理等缺点也逐渐暴露出来,且很难实现对具有空间任意角度平面零件(如网架节点球)的加工。根据当前国内外已有的并联机构的结构形式和其优缺点,基于并联机构理论,本文提出了一种新型并联机构——四自由度并联工作台,这种并联工作台可以与铣、镗、加工中心等机床组合使用,满足对具有任意角度平面零件的加工要求,对于扩大机床加工功能和提高机床工作效率有着重要意义。论文的主要工作包括以下几个方面: (1)通过对并联机构的分析,应用并联机构理论,研究确定了并联工作台的结构布局,简述了其工作原理,建立了工作台的运动学正解和逆解模型,并分析了影响其工作空间大小的因素。 (2)结合ZH5132型数控钻、铣加工中心工作空间的大小,确定了工作台的机构参数;根据已有并联机构零部件的结构特点和加工的实际要求,研究确定了并联工作台零部件的结构,提出一种新型伸缩杆结构,该伸缩杆由步进电机驱动,通过齿轮减速器把动力传给滚珠丝杆,再通过滚珠螺母和伸缩套筒实现伸缩作用。 (3)运用全参数化三维画图软件Pro/E4.0对工作台主要零部件进行了三维建模,并进行了虚拟装配和干涉检查,得到了并联工作台的虚拟样机。 (4)通过机械系统动力学仿真软件ADAMS对工作台虚拟样机进行运动学仿真分析,来验证并联工作台各个零部件之间相互位置关系和尺寸的合理性,通过实体仿真进一步验证工作台结构的合理性和可操作性。
[Abstract]:Parallel machine tool (PMT) is a creative application of spatial multi-ring mechanism in machine tool manufacturing industry. It is the product of combining parallel mechanism with modern machine tool technology. It can complement the traditional NC machine tool strongly. Although the parallel machine tool has the advantages of simple structure, high stiffness, light weight and fast response speed, with the development of the theory and technology of parallel mechanism, its manufacturing cost is high, the ratio of workspace to shape is unreasonable, and so on. And it is difficult to realize the machining of plane parts with any angle of space (such as grid node ball). According to the structure form, advantages and disadvantages of the existing parallel mechanism at home and abroad, based on the theory of parallel mechanism, this paper presents a new parallel mechanism-4-DOF parallel table, which can be milling, boring, and boring. The combined use of machine tools such as machining centers can meet the requirements of machining flat parts with arbitrary angles. It is of great significance to expand the machining function of machine tools and improve the working efficiency of machine tools. The main work of this paper includes the following aspects: (1) through the analysis of the parallel mechanism and the application of the parallel mechanism theory, the structural layout of the parallel worktable is studied, and its working principle is briefly described. The forward and inverse kinematic solution models of the worktable are established, and the factors influencing the workspace size are analyzed. (2) the mechanism parameters of the worktable are determined with the size of the workspace in the NC drilling and milling center of ZH5132; According to the structural characteristics of the parts and components of the existing parallel mechanism and the practical requirements of machining, the structure of the components of the parallel worktable is studied and determined, and a new type of telescopic rod structure is proposed, which is driven by a step motor. The power is transferred to the ball wire rod through the gear reducer, and then the ball nut and the telescopic sleeve are used to achieve the telescopic effect. (3) the main parts of the worktable are modeled by the fully parameterized 3D drawing software Pro/E4.0. The virtual prototype of the parallel worktable is obtained by virtual assembly and interference inspection. (4) the kinematics simulation analysis of the virtual prototype is carried out through the mechanical system dynamics simulation software ADAMS. In order to verify the rationality of the position relationship and dimension between the parts of the parallel worktable, the rationality and maneuverability of the structure of the parallel worktable are further verified by the entity simulation.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH112

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