【作者】 陈乾伟；

【导师】 赵淳生； 黄卫清；

【作者基本信息】 南京航空航天大学 ， 机械设计及理论， 2012， 博士

【摘要】 直线超声电机具有无电磁干扰、结构简单、设计灵活等特点，尤其它能直接实现直线运动并获得很高定位精度的优点，使之受到业界广泛关注。近些年，直线超声电机的基础理论研究和应用基础研究均获得长足进步，一些直线超声电机在德国、日本、美国、以色列等发达国家已进入产业化阶段，部分产品对一些高新技术装备的性能提升提供了强有力的支撑。经过近些年的锐意开拓，我国直线超声电机的研究开发工作取得了较大进展，但距离实际应用还有一定差距。本课题在国家自然科学基金重点项目“压电精密致动技术的基础研究”（No.50735002）的资助下，以多工作模式塔形拓扑结构直线型超声电机为研究对象，设计制作了三种不同塔形结构的原理样机，通过对比研究电机的不同驱动方式对输出性能的影响规律，揭示其微步进特性，建立高精度定位控制方法和措施，为直线超声电机在大行程情况下的微纳米级定位控制技术奠定基础。本论文的主要研究内容和成果如下：1、通过回顾直线型超声电机的发展历史和现状，概括了直线型超声电机的特点；对现有塔形结构直线超声电机和多工作模式直线超声电机进行了概述分析，明确了本课题的研究目标。按照超声电机驱动端面的理论运动轨迹对超声电机进行了分类，认为这种分类方法更容易将超声电机的多种工作模式及多种运行机理统一化。在此基础上，提出了将超声电机驱动端面的运动轨迹分为推程与回程运动轨迹，并对推程运动轨迹做功与回程运动轨迹做功进行比较的能量传递分析方法。通过对超声电机进行能量传递分析，得出了各类超声电机所共同遵循的能量传递规律。2、研究了双模态驱动直线超声电机的相关问题，包括异形工作模态的设计和接触边界条件的频率协调方法、定子支撑方法、预压力施加方式及其对定子最佳工作频率的影响规律。研制了一种工作模态控制解耦的塔形直线超声电机；采用了突变结构弹性支撑结构，用于缓解支撑对定子工作模态的影响；通过测定定子的工作模态频率与预压力的关系，获得了电机在共振运行模式下的最佳工作点；设计了基于三滚子结构的通用化的超声电机一维精密定位运动平台。3、提出了一类倾斜动子结构超声电机的设计方法，并研制了一种单模态驱动双向运动的斜轨塔形直线超声电机。分析了电机的工作原理及设计原则，并推导了电机运行的导轨倾角适用范围，为这一类直线超声电机的深化研究和工程设计提供了理论依据。4、发现了由非对称结构引起的塔形定子模态转化现象，并由此研制了一种单模态驱动双向运动的非对称定子结构的塔形直线超声电机。分析了非对称塔形直线超声电机的工作原理，为非对称定子结构这一类直线超声电机的深化研究和工程设计提供了理论依据。5、根据工作模态控制解耦塔形直线超声电机和非对称塔形直线超声电机的特性，分别为这两种超声电机设计了四种工作模式：共振连续运行模式、非共振连续模式、共振和非共振状态步进运行模式；通过四种工作模式的组合，建立实现大行程微纳米级精度的定位方法。实验表明，两种超声电机在共振连续运行模式可以实现高速稳定运行、在非共振连续运行模式可以实现低速稳定运行、在共振和非共振状态步进运行模式可以稳定实现纳米级（<100nm）微步距；因此四种工作模式的组合应用可以充分发挥这两种塔形直线超声电机在精确定位方面的潜力。这种思路可推广运用到其它类型的直线超声电机上。6、根据定子的振动能与能量阈值的关系对超声电机的瞬态特性和“死区特性”进行了理论研究，得出以下结论：超声电机的步距取决于超声电机的瞬态特性；超声电机的最小步距取决于超声电机的“死区”特性。对模态控制解耦塔形超声电机的“死区”特性进行了实验研究，用实验证实了“死区速度”的存在，进而证明了超声电机的最小步距存在极值。对模态控制解耦塔形超声电机和非对称结构塔形超声电机的纳米级精度步进实验数据进行了统计分析，得出超声电机纳米级精度步进运行的特点；提出了限制超声电机最小步距三个因素，并进而提出进一步降低超声电机步进运行的最小步距应采取的措施。更多还原

【Abstract】 Linear ultrasonic motor(LUSM) has characteristics of non-electromagnetic interference, simplestructure, flexible design, in particular, it is easy to obtain linear motion with high positioningaccuracy and so is paid more attention to in wide industry. Recently there is considerable progress ofLUSM on basic theory research and application research, and the technologies of LUSM in Germany,Japan, the United States, Israel and other developed countries have been employed to the stage ofindustrialization. Some of the products give a strong support to enhance the performance of some hightechnology equipment. Although the technologies on LUSM have made great progress in china bymuch more efforts in recent years, there is still a large gap from practical applications.This research is supported by the key projects of National Natural Science Foundation of “Basicstudies on piezo precision driving technology”(No.50735002). Choosing the multi-driving-patternLUSM with tower-shaped stator to study, the author designed three prototype motors with differentstructural tower-shaped stator; according to the comparative study between their different driving lawswith relative output performance, the characteristics of the micro-stepping is revealed, and thehigh-precision positioning control method is built up, as the foundation for micron-positioning ornano-positioning technologies of the tower-shaped LUSMs in the case of large stroke control. Toconclude, main research contents and achievements of this dissertation are as follows:1. The research status and the history of the development in LUSM are reviewed, and thecharacteristics of LUSM are summarized. that linear ultrasonic motor is of great significance for thedevelopment of modern science and engineering technology. The existing tower-shaped LUSMs andmulti-driving-pattern LUSMs are summarized and analyzed, obtaining a clear research objective ofthis subject. In accordance with the theoretical motion trajectory of the driving end on USM, theclassification of USM is completed, and this classification method is easier to unify manifold drivingpattern and driving mechanism of USM. On this basis, it is provided by the author that the motiontrajectory of the driving end is divided into two processes: push part and return part, and a new energytransfer analysis method is obtained by comparing the push part’s acting with the return part’s acting.Through the energy transfer analysis of ultrasonic motor, the energy transfer laws of every types ofultrasonic motors are gotten.2. The relative issues of dual-mode-driving LUSM are researched, including the design ofUSM’s operation modes of different mode shape, modal frequency harmonizing method in the contact boundary conditions, the stator’s supporting method, pre-pressure applying method and its influenceon the optimal operating frequency of the stator. A mode-control-uncoupling LUSM with atower-shaped stator is designed and manufactured. The support structure of elastic support withabrupt changing configuration is designed to release the impact of the stator’s supporting on theUSM’s operation modes; the optimum operating point of the mode-control-uncoupling LUSMworking in the resonance mode is obtained by testing the relationship between working modalfrequency and pre-pressure;a universal one-dimension and LUSM-driving precision moving stagebased on three roller structure are designed.3. The design method of a kind of USM with inclined rotor are put forward, and asingle-mode-drive bi-direction-moving LUSM composed of an inclined slider and a tower-shapedstator is designed and manufactured. The working principle and the design principles of the motor areanalyzed, and the obliquity range of the inclined slider which can make the motor running normallywas derived,which provides a theoretical basis to the farther research and engineering design of theinclined-rotor USM.4. The mode-conversion phenomenon of a tower-shaped stator arise from asymmetrical structureis discovered, and a single-mode-drive bi-direction-moving LUSM composed of a tower-shaped statorwith asymmetrical structure is designed and manufactured. The working principle of theasymmetrical-stator LUSM is analyzed, which provides a theoretical basis to the farther research andengineering design of the asymmetrical-stator LUSM.5. According to the features of and the mode-control-uncoupling LUSM and theasymmetrical-stator LUSM, four operating patterns are designed. The four operating patterns include:the resonant and continuous-moving pattern, the nonresonant and continuous-moving pattern, theresonant and step-moving pattern, the nonresonant and step-moving pattern. A large strokemicron-positioning or nano-positioning method is provided by a combination of the four operatingpatterns. The experiments show that the two motors can realize high speed moving in the resonant andcontinuous-moving pattern, and can realize low speed moving in the nonresonant andcontinuous-moving pattern, and can realize nano-scale(<100nm) step moving in the resonant andstep-moving pattern, and can realize nano-scale(<100nm) step moving in the nonresonant andstep-moving pattern. So the combination of the four operating patterns can sufficiently exert the twomotor’s ability to precise positioning, and this idea can be extended to other types of LUSM.6. According to the relationship between the stator’s vibration energy and energy threshold,USMs’ transient characteristics and dead-zone characteristics are analyzed, and come to the following conclusion: an USM’ step distance is dependent on its transient characteristics, and an USM’sminimum step distance is dependent on its dead-zone characteristics. An experiment on the dead-zonecharacteristics of the mode-control-uncoupling LUSM has been carried out. From the experiment it isfound that the dead-zone velocity exists. The phenomenon of the existing dead-zone velocity provethat an USM’s minimum step distance has an extremum. A statistical analysis of themode-control-uncoupling LUSM’s and the asymmetrical-stator LUSM’s experiment data on thenano-scale(<100nm) step moving is made, and LUSM’s characteristics of nano-scale(<100nm) stepmoving are obtained. Three main factors to limit LUSM’s smallest step are revealed to propose themethod for the further reduction of the minimum step of LUSM.更多还原