【作者】 王忠伟；

【导师】 程光明；

【作者基本信息】 吉林大学 ， 机械电子工程， 2004， 硕士

【摘要】 利用惯性冲击力形成驱动是构造运动机构的一种新方式。而冲击力大多数情况下是通过机械撞击获得的，控制相对较难且容易对机构造成损坏。由于压电元件具有响应速度快、能量转换效率高、结构简单、易于微小型化等优点。因此压电元件是构造惯性冲击式驱动机构的理想动力元件之一。而利用压电元件的快速变形产生惯性冲击力形成驱动的机构称为压电型惯性冲击式驱动器。 本文以压电双晶片为驱动源，基于惯性冲击运动原理设计并制作了一种两自由度压电型惯性冲击式精密驱动器样机，对其进行了试验测试。 全文共分五章，内容如下： 绪论 由于精密工程关键技术超精密定位的需求，压电驱动器得到了大力研究。冲击是振动的一种特殊形式，有其利弊，利用压电元件产生的冲击力构造驱动器也是最近新兴的精密驱动器研究领域。对精密驱动器的主要类型、压电<WP=82>驱动器的特点、类型和典型应用及驱动材料等进行了综述，认为压电材料在实现精密驱动上具有相当大的优势。同时也指出了目前国内外压电型精密驱动存在的问题。简述了国内外在压电惯性冲击方面的研究重点和研究成果。最后概述了本文的主要研究工作内容。 压电陶瓷性能分析与惯性冲击运动原理压电驱动的基础是压电效应和逆压电效应。 衡量压电陶瓷的性能参数主要有介电常数(、弹性常数s、压电常数d、机电耦合系数K、机械品质因数Qm、等，结合所选用的压电材料，本章着重介绍了PZT材料的介电常数矩阵、弹性常数矩阵和压电常数矩阵形式，将应用与有限元分析中。压电材料作为一种具有压电效应的弹性体，在不同的边界条件下，选择不同的自变量，有四组压电方程与之对应。压电双晶片采用了压电振子的LE振动模式，是一种输出位移大，可控性好，反应速度快，适合于惯性冲击精密驱动场合的压电元件。结合已有的悬臂梁式压电双晶片理论公式推导出压电晶片和基板尺寸参数对其自由端部位移、刚度和频率的影响趋势，为确定压电双晶片尺寸提供了理论依据。惯性冲击运动原理是所设计的压电型两自由度驱动器的原理依据，运用它构思出利用压电双晶片形成直线运动和旋转运动的方法。三. 惯性冲击式驱动器结构设计与分析在分析了试验室前期设计的两种平面内多自由度惯性冲击式驱动器结构的优缺点的基础上，提出新的驱动器结构方案—采用轴孔配合结构，能够<WP=83>实现轴向移动和绕轴心转动两个自由度运动，该结构便于运动导向和驱动力输出。通过试验测试和有限元计算两种方式对驱动器的核心驱动部件压电双晶片振子进行了静力学和动力学分析，得出了压电双晶片尺寸与其性能的一般关系，验证了第二章的理论分析。为了提高测试速度和准确性，编写了压电双晶片静变形、滞环和蠕变自动测试程序，大大方便了压电元器件的测试。分析了摩擦阻力影响和摩擦阻力调整装置的结构形式—柔性铰链，比较了弹簧调节和压电叠堆调节两种方式，以及弹簧选取要求。简要叙述了驱动器机械本体，包括机械底座、移动轴和连接件，在设计过程中应当注意的问题。四. 惯性冲击式驱动器的试验在分析了调节激励频率和调节激励幅值两种调节方式后，得出不同激励频率下压电双晶片振子的位移响应相位和幅值不同，而不同激励幅值作用下的位移响应相位相同，幅值不同，因此决定采用激励幅值调节方式实现驱动器步长和速度的调节。基于幅值调节方式，根据压电双晶片振子对不同频率有效ramp激励响应幅值的关系确定驱动器的驱动频率后，测试了驱动器的直线运动步长，带载能力、速度和旋转运动的步长和带载能力。测试结果为直线运动：最小稳定运动步长0.1μm，移动速度最大可以达到2mm/min，最大载荷能力为50g；旋转运动：最小稳定运动步长6.25μrad，最大载荷为15N·mm。在试验的基础上，提出了驱动器的控制策略。 五. 结论与展望 <WP=84>给出了全文的主要结论，并提出了下一步的深入研究内容。更多还原

【Abstract】 Inertial impact force is a novel kind of drive force to construct drive mechanism. At most cases, the impact force is produced by machinery rams, so control is more difficult relatively and is easy to damage the mechanism itself. Piezoelectric element has some advantages, such as high respond speed, high energetic conversion efficiency, simple structure and microminiaturization, therefore piezoelectric element becomes a type of powerful element of inertia impact drive mechanism. The drive mechanism, which uses the sharp deformation of piezoelectric element to produce inertia impact force, is called as piezoelectric inertial impact actuator. Based on the inertial impact principle, a 2-DOF inertial impact piezoelectric actuator prototype is made with the piezoelectric bimorphs as the drive mechanism and tested by this paper. The paper consists of five chapters, given as follows:Chapter 1 Introduction Because of the need of high precise location of precise engineering, piezoelectric actuator is paid more attention. Impact is a special form of vibration and has its advantages and disadvantages, To use impact as drive force is a new drive way. And it is also a new actuator research field to design precise actuator by the piezoelectric impact force. It conclude that piezoelectric material has large advantage over other materials in the precise drive field after reviewing the main types of precise drive, piezoelectric actuator’s main forms, characteristics and <WP=86>representative usage and the driving materials. At the same time, the problem that exits in the piezoelectric precise field at broad and home is put forward. Then a review about the research emphasis and research results of piezoelectric impact drive at broad and home is given. The main research content of the paper is list at last.Chapter 2 Piezoelectric performance analysis and the inertial impact drive principle The piezoelectric drive fundamental principles are piezoelectric effect and converse piezoelectric effect. The factors which influence performance include dielectric constant (、elastic constant s 、piezoelectric constant d 、electromechanically coupled coefficients K、mechanical quality factorQm,etc. With reference to the selected piezoelectric material, the dielectric constant matrix、elastic constant matrix、piezoelectric constant matrix of PZT is put out specially, which will be used in the FEM analysis in the chapter 3. Piezoelectric is a kind of elastic solids, it has four piezoelectric equations with different independent variable at various boundary conditions. Piezoelectric bimorph adopt the LE mode of piezoelectric oscillator and is a piezoelectric component with large deformation output, easy-to-control, higher response rapid which suits for the inertial impact precise drive. According to the previous cantilever beam piezoelectric bimorph equations, the trend is concluded that the dimension of piezoelectric wafer and base influence the beam’s free end displacement, the stiffness and frequency of the cantilever beam, which will be taken as the academic gist for designing the piezoelectric bimorph. Inertial impact drive principle is the academic base of 2-DOF piezoelectric inertial impact actuator, based on it, the way to utilize the piezoelectric bimorph to drive mechanism linear motion and rotation is given.Chapter 3 Inertial impact actuator structure design and analysis Based on comparing the planar multi-freedom inertial impact actuators structures designed by our lab, the paper provides a new design-axis vs. hole contact, by which the motion along axis and rotation around the center will be fulfilled and which is convenient for motion orientation and output of drive. By examination and FEM two means, the static and dynamic analysis of the <WP=87>piezoelectric bimorph oscillator is carried out in this paper, and the relation between the dimension of bimorph and the performance of it is got, which proves the conclusion in the chapter 2. In order to improve the test rapid and accuracy, an aut更多还原