基于3-PRRP（4R）并联机构的多维隔振装置的优化设计与性能分析

发布时间：2018-05-09 21:39

本文选题：并联机构 + 多维隔振　；参考：《山东大学》2017年硕士论文

【摘要】：在航空航天、交通运输及机械制造等环境中,设备会受到大量多维振动和冲击的影响,这严重降低了设备的工作性能和使用寿命,甚至还会导致事故的发生,造成巨大的经济和人员损失,如何有效地消除振动和冲击所带来的危害是广大研究人员急需解决的一个问题。一般情况下,通过在振源和所需隔振的设备之间安装隔振器,切断振动的传递路径,实现振动的隔离,是一种有效的减振措施,然而传统的有关隔振的理论和方法不能很好地满足现在工程实际的要求。并联机构是一种结构简单、精度高、刚度大、易于制造、多输入多输出的多自由度系统,相关研究表明,通过在并联机构的原动件和机架之间安装弹簧阻尼装置所构建的多维隔振装置,可以有效实现特定工况下的多维隔振。本文在国家自然科学基金"高铁等超大型结构宽频声振预报的混合能量流方法"(51675306)、"基于柔性变胞机构的精密设备多维振动的主动控制研究"(51275275),国家重点研发计划项目"大型机加厂房等典型场所噪声及电焊烟尘防护技术装备研发"(2016YFC0801704)、"密集抛光打磨车间粉尘及振动危害防护技术装备研发"(2016YFC0801702)资助下,针对多维隔振问题,构建了基于并联机构的多维隔振装置,对多维隔振装置制定科学合理的性能评价指标和基于工况要求的参数优化设计方法进行了探索。第一,根据工程实际中最常见的三平移多维振动形式,在课题组所做研究的基础上,选取了一种3-PRC三平移并联机构作为多维隔振装置的主体机构,为消除该机构中存在的缺陷,对部分结构进行改进设计,得到3-PRRP(4R)并联机构,运动输出分析表明,3-PRRP(4R)机构具有三个平移自由度,满足三平移隔振装置对机构运动输出形式的要求。第二,建立了 3-PRRP(4R)并联机构的运动学模型,通过ADAMS仿真验证了理论模型的正确性,求得了机构的工作空间,分析了在工作空间内机构奇异性和灵巧度随空间位置的变化情况,结合多维隔振装置对工作空间形状和运动学性能的要求,提出了优质球形空间的概念,详细分析了构件尺寸参数对机构工作空间、优质工作空间和优质球形空间体积的影响规律。第三,构建了基于3-PRRP(4R)并联机构的多维隔振装置,建立了隔振装置的静力学模型,通过ADAMS仿真验证了理论模型的正确性,推导出了隔振装置的等效刚度模型,以一种通俗易懂、清晰直观的方式描述装置的刚度特性;在忽略支链质量的条件下建立了装置的自由振动微分方程,通过忽略支链质量和包含支链质量两种仿真方式验证了理论模型的正确性和假设条件的合理性,讨论了上平台质量对理论模型精度的影响;通过频率响应仿真,得到了装置的频率响应特性及有效隔振的频率范围,讨论了构件参数对隔振装置固有频率和模态振型的影响特性,设计了一种通过改变装置初始位置以改变隔振装置固有频率的装置。第四,基于并联机构的多维隔振装置设计方法,采用遗传算法实现了基于特定固有频率的装置参数优化设计;针对一般工况要求,采用遗传算法实现了基于优质球形空间体积和最大固有频率的装置参数优化设计;优化后的装置具有良好的运动学性能和更大的有效隔振频率范围,具有显著的多维隔振效果;最后,按照优化后的尺寸制作了隔振装置样机。本文在基于并联机构的多维隔振装置的研究中所提出的优质球形空间结合了隔振装置度对机构工作空间形状、体积及运动学性能的要求,科学合理;等效刚度通俗易懂、易于为工程人员掌握;基于特定固有频率及基于优质球形空间体积和最大固有频率的参数优化设计方法与工程实际结合紧密。研究成果对基于并联机构的多维隔振装置的设计与评价、推广与应用具有一定的指导意义,对有效解决多维振动问题具有一定的参考价值。
[Abstract]:In the environment of Aeronautics and Astronautics, transportation and machinery manufacturing, equipment will be affected by a large number of multidimensional vibration and impact, which seriously reduces the working performance and service life of the equipment, even leads to the occurrence of accidents, resulting in huge economic and personnel losses, and how to effectively eliminate the hazards caused by vibration and impact. In general, it is an effective damping measure by installing the isolator between the vibration source and the required vibration isolation equipment, cutting off the transmission path of the vibration and isolating the vibration. However, the traditional theory and method of vibration isolation can not meet the requirements of the actual engineering. The mechanism is a multi degree of freedom system with simple structure, high precision, large stiffness, easy to manufacture and multi input and multi output. The related research shows that multidimensional vibration isolation system can be effectively realized by installing a spring damping device between the original moving parts and the frame of the parallel mechanism, and it can effectively realize multidimensional vibration isolation under specific conditions. "Hybrid energy flow method" (51675306), "study on active control of multidimensional vibration of precision equipment based on flexible cell mechanism" (51275275), "Research on the noise of the typical field of large machine building and other typical fields and welding smoke and dust protection technology and equipment" (2016YFC0801704), "(51275275)," Under the support of the research and development of the dust and vibration hazard protection equipment in the intensive polishing and grinding workshop (2016YFC0801702), the multidimensional vibration isolation device based on the parallel mechanism is constructed to solve the multidimensional vibration isolation problem. The scientific and reasonable performance evaluation index and the parameter optimization design method based on the requirements of the working condition are explored. First, on the basis of the most common three translational multidimensional vibration form in the engineering practice, on the basis of the research of the project group, a 3-PRC three translation parallel mechanism is selected as the main body of the multidimensional vibration isolation device. In order to eliminate the defects in the mechanism, some structure is modified, and the 3-PRRP (4R) parallel mechanism is obtained and the movement output is divided. The analysis shows that the 3-PRRP (4R) mechanism has three translational degrees of freedom to meet the requirement of the motion output form of the three translational vibration isolation device. Second, the kinematic model of the 3-PRRP (4R) parallel mechanism is established. The correctness of the theoretical model is verified by the ADAMS simulation, the working space of the mechanism is obtained, and the mechanism singularity in the workspace is analyzed. With the change of the space position and the change of the space position, the concept of high quality spherical space is put forward according to the requirements of the multi-dimensional vibration isolation device for the shape and kinematics of the workspace. The influence rules of the component size parameters on the working space of the mechanism, the high quality working space and the high quality spherical space volume are analyzed in detail. Third, the 3-PRR is built on the basis of the structure. The multidimensional vibration isolation device of the P (4R) parallel mechanism has established the static model of the vibration isolation device. The correctness of the theoretical model is verified by the ADAMS simulation. The equivalent stiffness model of the vibration isolation device is derived. The stiffness characteristics of the device are described in a popular and clear way, and the device is established under the condition of neglecting the quality of the branch chain. The differential equation of free vibration is used to verify the correctness of the theoretical model and the reasonableness of the hypothesis by neglecting the two simulation methods of the quality of the branched chain and the mass of the branched chain. The influence of the quality of the upper platform on the accuracy of the theoretical model is discussed. The frequency response characteristic and the frequency range of the effective isolation are obtained by the frequency response simulation. The influence characteristic of component parameters on natural frequency and modal shape of vibration isolation device is discussed. A device that changes the natural frequency of vibration isolation device by changing the initial position of the device is designed. Fourth, the design method of multidimensional vibration isolation device based on parallel mechanism is designed, and the parameter optimization based on the specific natural frequency is realized by genetic algorithm. In view of the general condition requirements, the genetic algorithm is used to optimize the design of the device parameters based on the high quality spherical space volume and the maximum natural frequency. The optimized device has good kinematic performance and a larger effective vibration isolation frequency range, and has a significant multidimensional vibration isolation effect. Finally, the optimized size is made in accordance with the optimized size. The high quality spherical space proposed in the study of multidimensional vibration isolation device based on parallel mechanism combines the requirements of the vibration isolation device degree to the shape of the workspace, the volume and the kinematics of the mechanism. The equivalent stiffness is easy to understand and is easy to master for the engineers; based on the specific natural frequency and the quality based on the high quality The parameter optimization design method of spherical space volume and maximum natural frequency is closely connected with the engineering practice. The research results have certain guiding significance for the design and evaluation of multidimensional vibration isolation device based on parallel mechanism, popularization and application, and have certain reference value for solving the problem of multidimensional vibration effectively.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB535.1

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