共查询到18条相似文献,搜索用时 46 毫秒
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一种无耦合位移和低集中应力的二维微操作器研究 总被引:1,自引:0,他引:1
集中应力和耦合位移是影响基于柔性铰链和压电陶瓷驱动器的微操作器性能的关键因素。单平行四杆机构具有低的集中应力,但存在大的耦合位移,双平行四杆机构没有耦合位移但存在较大的集中应力。在分析上述2种经典微操作器机构优缺点的基础上,吸取每一种机构的优点,摈弃各自的缺点,构建了一种复合四杆机构,并对这3种机构进行了对比分析,用有限元仿真的结果证明了理论分析的正确性。本文还设计加工了3种类型的二维微操作器柔性铰链机构与压电陶瓷驱动组成二微维操作器,并进行了对比实验研究,实验结果表明,该复合四杆微操作器性能优于经典的平行四杆微操作器和双平行四杆微操作器。 相似文献
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为保证压电柔顺微操作器的精准性和稳定性,以压电纤维驱动的单自由度柔性微操作器为例,首先,通过在传统Prandtl-Ishlinskii(简称PI)迟滞模型上串联死区算子,建立改进PI迟滞模型并设计相应前馈控制器;其次,将系统模型分解为线性可逆分量和有界分量,并构建权重函数和增广模型设计H∞反馈控制器,以保证系统的稳定性和精准性;最后,以压电纤维驱动的单自由度柔性微操作器为例,搭建实验测控系统。实验结果表明:在前馈控制下,压电柔顺微操作器的迟滞量从16.5%下降到4.4%,改进PI迟滞模型是可行的。当参考轨迹为阶跃和不同频率的正弦信号、甚至改变微操作器结构参数时,H∞反馈控制均能有效跟踪给定参考信号且相对控制误差较小,验证了所设计H∞反馈控制器的有效性。 相似文献
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基于对压电陶瓷材料的特性研究,利用压电陶瓷的逆压电效应,压电陶瓷双晶片通过组合设计得到压电驱动元件,分析了在电激励条件下,压电陶瓷双晶片悬臂端振动通过摩擦力和惯性力驱动转子转动并输出转距的原理,研制了一种基于摩擦式的压电电机.研究了压电电机输出转速、转矩特性与激励电压频率之间的关系,试验表明:压电电机具有良好的输出特性,响应快、发热很少、转动平稳且可实现双向回转,结构简单,容易实现闭环控制.此设计为进一步研究实用的小型化、低成本、高效率的压电电机提供了一种新的设计方法. 相似文献
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研制出了尺寸为30 mm×30 mm×50 mm的压电陶瓷驱动的球基微驱动器样机,并对该微驱动器进行动力学分析以及微型轴孔装配的实验研究。建立了微驱动器金属球空间坐标关系,分析了球基微驱动器的动力学特征,并建立了其动力学模型。采用龙格-库塔法计算出了微驱动器的动力学参数,并利用MATLAB的SIMULINK模块搭建了微驱动器的仿真模型,并对其进行了动力学仿真分析。研制出了球基微驱动器样机,并在此基础上,集成微夹持器形成微操作器,对微驱动器性能进行了实验测试,并开展了Φ180 μm微型轴与Φ200 μm微型孔之间的精密微装配实验研究。最后,分析了微驱动器金属球质量、驱动信号频率、以及金属球与微驱动单元摩擦块接触表面摩擦系数对其性能的影响。实验结果表明:该球基微驱动器的转动分辨率为0.000 1°,转动定位精度为0.000 5°,微驱动器最大工作频率为1 200 Hz。实验结果验证了逆转振动模型的正确性,由该微驱动器所集成的微操作器,完全可以满足对微小元器件的微米级操作与装配等精密作业的要求。 相似文献
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为从理论上获得压电泵在薄片型压电双晶片和单晶片(统称压电振子)驱动时的输出流量关系,需要获得二者振动时产生的容积变化量。假设压电振子在周边固定约束条件下,应用弹性薄板的小挠度弯曲变形理论,推导了压电双晶片和单晶片振动时的容积变化方程,并根据方程对铜基板直径为35mm,压电陶瓷直径为29mm,基板和压电陶瓷厚度同时为0.2mm和0.3mm 2种规格的压电单晶片和双晶片进行了振动容积计算。计算结果显示,相同基板和陶瓷厚度的双晶片振动产生的容积变化量是单晶片的2.3倍。将上诉压电振子应用到单腔压电泵上进行输送气体流量测试,获得的实际输出流量比在1.5~2倍之间,理论计算结果与试验测试结果比较接近。理论推导结果为比较双晶片和单晶片驱动下压电泵的输出能力提供了可靠依据。 相似文献
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针对全闭环数控回转轴的关键检测元件—圆光栅的安装误差引起回转轴定位精度差的问题,基于圆光栅测量角度的工作原理,分析了圆光栅在安装时由于光栅定位端面的跳动误差对莫尔条纹的影响规律,推导出了相应的数学关系,建立了回转轴定位误差与光栅定位端面的跳动误差之间的数学模型.数值仿真表明当圆光栅出现端面定位安装误差后,回转轴回转一周,输出的莫尔条纹光强变化经历了一个周期,近似为一正弦曲线.针对上述理论分析,在加工中心回转轴C轴上进行了实验研究,结果表明,通过调整圆光栅端面的跳动误差从原来的70 μm到16 μm,利用高精密单频激光干涉仪对回转轴的定位误差进行了检测,两次测量的定位误差曲线均为正弦曲线,且回转轴的定位精度提高了3倍.研究结果表明,减小圆光栅定位端面的轴向跳动误差可有效提高回转轴的定位精度. 相似文献
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Dr E. S. Lee H. G. Wi 《The International Journal of Advanced Manufacturing Technology》1998,14(5):330-335
A method for measuring the accuracy of rotating objects was studied. Rotating axis errors are significant; such as the spindle error of a machine tool which results in increased surface roughness of machined work pieces. Three capacitance-type displacement sensors were used to measure the position of a rotating master ball. The sensors were mounted at the three orthogonal points on the spindle axis. The measurement data were analysed for rotating spindle accuracy, not only for the average roundness error but also for the spindle volumetric positional error during rotation. This method is simple and economical for industrial field use for regular inspection of spindles using portable equipment. The time taken for measurement and analysis using this method is only about two hours. This method can also measure microscopic amplitudes in 3-D directions of vibrating objects. 相似文献
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Chengyuan LIANG Fang YUAN Xuedong CHEN Wei JIANG Lizhan ZENG Xin LUO 《Frontiers of Mechanical Engineering》2019,14(3):255
Nano-precision positioning stages are characterized by rigid-flexible coupling systems. The complex dynamic characteristics of mechanical structure of a stage, which are determined by structural and dynamic parameters, exert a serious influence on the accuracy of its motion and measurement. Systematic evaluation of such influence is essential for the design and improvement of stages. A systematic approach to modeling the dynamic accuracy of a nano-precision positioning stage is developed in this work by integrating a multi-rigid-body dynamic model of the mechanical system and measurement system models. The influence of structural and dynamic parameters, including aerostatic bearing configurations, motion plane errors, foundation vibrations, and positions of the acting points of driving forces, on dynamic accuracy is investigated by adopting the H-type configured stage as an example. The approach is programmed and integrated into a software framework that supports the dynamic design of nano-precision positioning stages. The software framework is then applied to the design of a nano-precision positioning stage used in a packaging lithography machine. 相似文献
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The dynamic characteristics of stick-slip motion in reciprocating friction drive systems are investigated under dry contact using a 0.45% carbon steel pair. Based on this dynamic analysis, the stick-slip motion can be eliminated under certain experimental conditions depending upon driver speed, normal load and spring constant. The effects of normal load, driver speed, and spring constant on the positioning accuracy of the reciprocating friction drive system are examined under harmonic oscillation without stick-slip motion. Results show that at very low spring constants, the slip increases with increasing driver speed such that higher normal load has better positioning accuracy or smaller slip than does lower normal load. However, at high spring constants and high normal loads, there exhibits severe wear or peak at two limit positions on the sliding region. As a result, smaller normal loads have a better positioning accuracy than larger normal loads due to severe wear at high normal loads. 相似文献