驱动器用陶瓷材料发展与展望

叙述了适用于制造驱动器的几种陶瓷材料,即压电陶瓷、电致伸缩陶瓷、相转变（反铁电-铁电）陶瓷和弛豫基铁电单晶材料,并对它们各自的优缺点及特性作了简单的评述,同时展望了它们在驱动器领域的应用前景。     

压电、电致伸缩传动器及其应用

本文介绍了近年来压电和电致伸缩传动器的发展状况,重点介绍了目前发展较快的几种传动器。     

提高输出推力的蠕动式微进给定位机构

蠕动式压电／电致伸缩微进给机构具有在保持高位移分辨率的同时实现大位移行程的特点,但迄今进给刚度和推力较小,以及不连续进给运动的不足之处制约了蠕动机构的实际应用。本文作者研究通过采用柔性铰链构成的周向分布式杠杆箝位机构的设计,研制出一种提高轴向刚度和输出推力的蠕动式压电／电致伸缩微进给机构,并进行了机构性能的初步测试,探讨了连续运动控制和超精密定位控制方法     

两种压电陶瓷微位移器的特性分析与实验对比

压电和电致伸缩材料，根据其压电和电致伸缩效应，可作为新型的微位移器件。它具有结构紧凑、体积小、分辨率高、控制简单等优点。不存在发热问题，容易实现０．０１μｍ的位移精度。在精密机械及航空航天精密工艺中得到了广泛应用。本文对这两种材料的机电耦合效应进行了描述。并通过实验曲线对两种典型的压电和电致伸缩材料的特性进行了分析对比，指出了各自的适用范围。     

一种新型压电陶瓷驱动电路

一种新型压电陶瓷驱动电路浙江大学傅卫压电陶瓷作为一种精度高的工作台微动机构，是不少精密仪器所必不可少的。它利用加在其上面的电压。通过压电晶体的电致伸缩特性，产生与电压相应的形变，推动工作台移动。精度达几至几十纳米，形变总量一般可达几十微米。但它所需电...     

压电-电流变平面二维步进式驱动器

首次提出了一种利用压电效应和电为效应相结合的新型平面步进式驱动器,研制的驱动器包括４个提供驱动力和产生位移的以压电致动器,以及４个用来箝位器,根据仿生运动模式,箝位器与压电致动器采用不同的运动组合,可分别实现沿ｘ和或ｙ向的蠕动式步式运动,实验结果显示,平面步进驱动器机在ｘ向和ｙ向都能灵活运动,并具有大行程和低于０．１μｍ的高的分辨率特性,驱动器的最高步进速度为６ｍｍ／ｍｉｎ最大承载能力为１．７０Ｎ     

电可控机电耦合特性的研究

基于经典的压电学第一，第二类方程，引入铁电体中普遍存在的电致伸缩效应，本文导出了电可控机电耦合特性的关系式，该式表明电可控机电耦合效应主要起源于铁电体的电致伸缩效应，电致伸缩效应愈强，可控范围愈大；具有弥散相变的铁电体可控范围要远大于尖锐相变的铁电体。理论结果和实验相一致。     

微系统工程中的新型致动器——意义，示例与再发展的可能性

现代致动器对于德国工业中出口产品的行业至关重要，因为它通过其竞争能力发挥决定性作用。特别是对于配有压电、磁致伸缩和电致伸缩固体变换器的新型致动器，对于具有形状记忆合金、电磁流变和电致伸缩流变液体的致动器以及电化学致动器，微型致动器和电磁小型驱动机构，存在明显上升的趋势。     

压电与压磁声电转换材料的研究及应用

对应用于声电转换方面的两类材料－压电与压磁声电转换材料的制备作了研究，对它们的压电效应与压磁效应、电致伸缩与磁致伸缩及其应用作了归类比较。并且指出，在有些重要应用方面它们将长期共存及相互不可替代。     

压电谐波电机承载能力的研究

以保证柔轮与刚轮的正常啮合为条件,引入计算径向变形量系数,设计径向变形量系数以及允许位移损失系数,通过确定位移放大机构输出端允许位移损失量或柔轮的实际径向变形量,计算压电谐波电机承载能力。建立了压电谐波电机承载能力的设计准则,是包括压电驱动器驱动能力选择以及其他结构尺寸设计与校核的主要依据。其输出扭矩与压电驱动器与位移放大机构的刚度成正比,与柔轮变形力、轮齿啮合角以及摩擦系数成反比。克服了基于压电驱动器最大驱动能力建立压电谐波电机输出扭矩方法的缺陷。该模型也可用于采用超磁致伸缩等其他驱动器的谐波电机承载能力的计算。设计计算表明,相对于一般原动机,压电谐波电机能提供较大的输出扭矩。     

Complex Effective Dielectric Permittivity of Micromechanically Tunable Microstrip Lines

It is considered an influence of physical-topological parameters of controlled microstrip lines where characteristics modification is achieved by signal electrode movement over the substrate on effective dielectric permittivity and electromagnetic energy loss in the line expressed in form of complex permittivity. There are stated the ways of increase of sensitivity of effective dielectric permittivity modification to signal electrode shift and loss decrease. There are determined ultimate characteristics of tuning and loss. There are represented calculations of transfer factor effective permittivity corresponding to experimental results. These results can be used for development of controlled resonant elements and phase shifters with application of electrically tunable micromovement devices, such as piezo- and electrostrictive actuators or microelectromechanic systems. Due to application of invariant relations of physical-topological parameters represented calculations are suitable for estimation of tuning factors and loss of devices with micromechanical control in a wide range of operating frequency with application of wide range of materials.     

Temperature‐Insensitive (K,Na)NbO3‐Based Lead‐Free Piezoactuator Ceramics

The development of lead‐free piezoceramics has attracted great interest because of growing environmental concerns. A polymorphic phase transition (PPT) has been utilized in the past to tailor piezoelectric properties in lead‐free (K,Na)NbO₃ (KNN)‐based materials accepting the drawback of large temperature sensitivity. Here a material concept is reported, which yields an average piezoelectric coefficientd₃₃ of about 300 pC/N and a high level of unipolar strain up to 0.16% at room temperature. Most intriguingly, field‐induced strain varies less than 10% from room temperature to 175 °C. The temperature insensitivity of field‐induced strain is rationalized using an electrostrictive coupling to polarization amplitude while the temperature‐dependent piezoelectric coefficient is discussed using localized piezoresponse probed by piezoforce microscopy. This discovery opens a new development window for temperature‐insensitive piezoelectric actuators despite the presence of a polymorphic phase transition around room temperature.     

Laser glass composition and the possibility of eliminating electrostrictive effects

Many authors have stated that electrostrictive self-trapping of the light beam initiates laser damage in solid transparent dielectrics. By systematically varying composition, it may be possible to find a glass in which electrostrictive effects are eliminated.     

Progresses in Tensile,Torsional, and Multifunctional Soft Actuators

Soft actuators have received intensive attention in the fields of soft robots, sensors, intelligent control, artificial intelligence, and visual intelligence. By combination of tensile and torsional deformations, different types of motions can be realized, such as bending, rolling, and jumping. Soft robotics need soft actuators, such as artificial muscles to lift or move objects to perform some work. Additionally, actuation integrated with functions of sensing, signal transmission, and control is also needed in the development of advanced intelligent systems, which further stimulates the requirement of multifunctional actuators. Here different types of soft actuators that can perform tensile and torsional actuations are summarized, including twisted fiber artificial muscles, shape memory polymers, hydrogels, liquid crystal polymers, electrochemical actuators with conducting polymers, and some natural materials. Examples are also included regarding the bending or rolling deformations of the actuators for lifting objects. Then, recent interesting reports about multifunctional soft actuators combined with sensing and signal transmission performances, are summarized. Last, a summary of different ways to realize tensile and torsional actuations, different materials, and designs for lifting or moving objects, as well as construction of multifunctional actuators with actuation and sensing functions is provided.     

Mechatronic design and control of singly and doubly curvedcomposite mesoscale actuator systems

Recently, the design of curved mesoscale actuators (deflections from 1 to 15 mm) has been a topic of study for many researchers. The work in this paper deals with the development of a comprehensive modeling technique for dealing with curved actuators. First, the formulation begins with the equations of motion for a general shell surface. Second, relationships for reducing the equations to those for known actuators are given. The technique can be applied to a broad array of curved actuators. These actuators include but are not limited to rainbow actuators, thunder actuators, and basic C-block actuators. Next, the technique is then experimentally verified on a stack of rainbow actuators. Finally, the system is controlled using both classical and intelligent control techniques. In addition, hardware and circuitry issues are explored     

Mixing and detection of microwave signals in fibre-opticelectrostrictive sensor

The nonlinear strain-polarisation relationship in electrostrictive ceramics is exploited to demonstrate, for the first time, detection and mixing of microwave signals in a fibre-optic electrostrictive sensor. The nonlinear electrostrictive transducer mixes the microwave signal with a signal from a local oscillator, and the resulting strain at the intermediate frequency is detected with a fibre-optic interferometer. The sensor demonstrated approximately flat response in the microwave regime (up to 20 GHz) with a resolution of 5×10^-6 V/√ Hz     

Application of MEMS technology in automotive sensors and actuators

Sensors and actuators are the critical system components that collect and act on information in the analog environment and link it to the world of digital electronics. The functional groups of sensors, software, controller hardware, and actuators from the backbone of present and future automotive systems. Unit volumes for sensors and actuators in the automotive industry are measured in millions per year and at a unit cost of a few dollars. The design of sensors and actuators has increasingly made use of microelectromechanical systems (MEMS) technology. This technology is well suited to producing a class of micromachined sensors and actuators that combines signal processing and communications on a single silicon chip or contained within the same package. This paper contains a discussion of the issues in producing MEMS sensors and actuators from the concept selection stage to the manufacturing platform. Examples of commercial and emerging automotive sensors and actuators are given, which illustrate the various aspects of device development. Future trends in MEMS technology as applied to automotive components are also discussed     

Electric Actuation of Nanostructured Thermoplastic Elastomer Gels with Ultralarge Electrostriction Coefficients

Electrostriction facilitates the electric field‐stimulated mechanical actuation of dielectric materials. This work demonstrates that introduction of dielectric mismatched nanodomains to a dielectric elastomer results in an unexpected ultralarge electrostriction coefficient, enabling a large electromechanical strain response at a low electric field. This strong electrostrictive effect is attributed to the development of an inhomogeneous electric field across the film thickness due to the high density of interfaces between dielectric mismatched periodic nanoscale domains. The periodic nanostructure of the nanostructured gel also makes it possible to measure the true electromechanical strain from the dimensional change monitored via in situ synchrotron small angle X‐ray scattering. The work offers a promising pathway to design novel high performance dielectric elastomers as well as to understand the underlying operational mechanism of nanostructured multiphase electrostrictive systems.     

Solid-State Physical Transducers for Biomedical Research

The development of solid-state sensors and actuators during the last decade is reviewed, with emphasis on solid-state physical transducers for the measurement or control of the physical parameters in biomedical instrumentation systems. The principles and performance of electrodes, sensors for temperature, position, motion, pressure, fluid flow, and humidity, as well as actuators, are briefly discussed. Selective references on physical sensors and actuators are listed.