六自由度微位移定位平台的设计与试验  

Design and Experiment of 6-DOF Micro-displacement Positioning Stage

作　　者：季瑞南[1] 金家楣[1] 张建辉[1,2] JI Ruinan;JIN Jiamei;ZHANG Jianhui(State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronau ics and Astronautics Nanjing,210016,China;School of Mechanical and Electric Engineering,Guangzhou University Guangzhou,510006,China)

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016 [2]广州大学机械与电气工程学院,广州510006

出　　处：《振动．测试与诊断》2019年第6期1264-1270,1363,共8页Journal of Vibration,Measurement & Diagnosis

基　　金：国家自然科学基金资助项目(51775263)

摘　　要：压电叠堆与柔性机构构成了微位移的基本形式,其行程与精度、输出力的矛盾需要结合应用要求对结构进行综合设计。针对所构建的超精密加工工具对六自由度微位移的需求,提出了一种以压电叠堆作为驱动元件,以柔性铰链和楔形机构作为传动机构的空间六自由度微位移定位平台。由于压电叠堆需要一定的预紧力才能发挥其微位移精度和输出力的优势,通过静力分析,得出了微位移平台各个自由度驱动力和位移输出关系的表达式及刚度表达式,对结构进行了优化。试验表明,各自由度的行程与分辨率如下:x,y,z方向的最大位移分别为7.48,8.33和4.14μm,分辨率为0.01μm;沿θx,θy,θz方向的最大旋转角度均为0.13°,分辨率为0.01°,满足所构建的超精密加工工具定位的精度要求。试验获得了微位移定位平台的激励电压与各自由度位移输出曲线,为平台的运动、定位控制提供了依据,也为柔性铰链机构和楔形机构在其他结构中的应用提供了理论依据和试验基础。Piezoelectric stacks and flexure mechanisms constitute the fundamental forms of micro-displacement positioning.Its comprehensive structure design includes the contradictions between stroke and output force caused by the application requirements.To satisfy the requirement of six degrees of freedom(6-DOF)micro-displacement for ultra-precision machining tools,we put forward a 6-DOF micro-displacement positioning stage,which is driven by piezoelectric stacks and uses flexure mechanism and wedge mechanism for transmission.In order to obtain high micro-displacement precision and high output force of piezoelectric stacks,a certain level preload is needed.On the basis of the relational expression between driven force and displacement in each degree of freedom and stiffness expression obtained by static analysis,the structure of the stage is optimized.Experiment results show that the maximum displacement in x,y,zdirection is 7.48μm,8.33μm,and 4.14μm with the resolution of 0.01μm;the maximum rotation angle inθx,θy,θzdirection is 0.13°with the resolution of 0.01°.Therefore,this positioning stage meets the requirements for an ultra-precision machining tool,which means piezoelectric stacks and flexure mechanisms can meet the requirements of both stroke and output force through rational design.The relationship curve of driven voltage and output displacement in each direction obtained by experiments provides the basis for movement and positioning control and also offers the theoretical and experimental basis for the application of flexure hinge mechanism and wedge mechanism in other structures.

关 键 词：六自由度 微定位平台 压电叠堆 柔性机构 楔形机构 

分 类 号：TN384[电子电信—物理电子学] TH113.22[机械工程—机械设计及理论]