超声波电机稳态运行的建模和仿真

研究超声波电机稳态运行的模型建立问题,由于传统电机稳态模型过于复杂和计算量大,影响超声波电机系统的性能优化。为解决上述问题,改善模型的复杂程度,提出用Kirchof薄板理论为基础,将超声波电机的定转子接触简化为一个二维弹性接触问题的方法来建模,并且用matlab进行软件仿真超声波电机模型。通过仿真获得的超声波电机的稳态运行数据,与实际测量值比较吻合的较好。实验证明,建立的模型简洁,计算时间短,为环形行波型超声波电机的进一步开发和性能优化提供了基础。     

超声电机及其在机器人驱动中的应用

声波电机(Ultrasonic Motor,简称USM)是一种近二十年来发展起来的一种利用超声波振动能作为驱动源的新原理电机.以行波型超声电机为例,介绍超声电机原理结构、特点及其驱动控制技术,并以超声电机驱动的二轴机械臂控制系统为例子介绍超声电机在机器人控制、执行中的应用.     

Motion control with deadzone estimation and compensation using GRNN for TWUSM drive system

The traveling wave ultrasonic motor (TWUSM) drive has a strong nonlinearity, which varies with driving conditions and possesses variable deadzone in the control input associated with the phase difference of applied two-phase AC driving voltages. This deadzone is a problem as an accurate positioning actuator for industrial application, and it is important to eliminate the deadzone in order to improve the control performance. To overcome the above problems, a new motion control scheme with deadzone estimation and compensation using generalized regression neural network (GRNN) is proposed in this paper to improve the control performance of the TWUSM drive system. One of them is to approach the nonlinearity deadzone part of the TWUSM drive system, and another one with extension form is to approach the inverse of nonlinearity deadzone to realize the dynamic compensation. Once the nonlinearity of deadzone is compensated exactly by its inverse compensation, the whole TWUSM drive system can be treated as linear, and the estimated parameters of the linear system can be adopted to design a controller for a desired reference command.     

基于超声电机的护理机器人的设计与实现

以超声电机为驱动元件,设计并实现了双平行四边形结构的护理机器人。根据行波型超声电机的特性,利用调节频率的方式结合闭环理论进行速度控制,利用查表的方法实现了圆形轨迹的控制。实验结果表明,该系统运行稳定且精确。     

Design of a PCB stator coreless axial flux permanent magnet synchronous motor based on a novel topology Halbach array

A novel topology Halbach permanent magnet array is proposed and applied to the design of a printed circuit board (PCB) axial flux permanent magnet (AFPM) motor. Compared with the traditional coreless AFPM motor, this novel topology for a Halbach permanent magnet array PCB stator AFPM motor has larger air-gap magnetic flux density and air-gap flux per pole. The magnetic flux leakage is effectively reduced, and the air-gap magnetic density is close to the sine wave. Results of the finite element analysis and prototype experiments verify the feasibility and effectiveness of the novel Halbach permanent magnet array PCB stator motor. A reference basis and practical value for the design of the PCB AFPM motor are provided.

     

Piezoelectric micromotors for microrobots

The authors have begun research into piezoelectric ultrasonic motors using ferroelectric thin films. The authors have fabricated the stator components of these millimeter diameter motors on silicon wafers. Ultrasonic motors consist of two pieces: a stator and a rotor. The stator includes a piezoelectric film in which bending is induced in the form of a traveling wave. A small glass lens placed upon the stator becomes the spinning rotor. Piezoelectric micromotors overcome the problems currently associated with electrostatic micromotors such as low torque, friction, and the need for high voltage excitation. More importantly, they may offer a much simpler mechanism for coupling power out. Using thin films of lead zirconate titanate on silicon nitride membranes, various types of actuator structures can be fabricated. By combined new robot control systems with piezoelectric motors and micromechanics, the authors propose creating micromechanical systems that are small, cheap and completely autonomous     

行波型超声波直线电机的效率研究

针对关于行波型超声波直线电机效率问题方面的误区,按照行波型超声波直线电机的输入、输出功率关系,重新进行效率的定义,并提出效率计算式.     

一种二维力/扭矩传感器的设计

针对用于测试旋转型行波超声电机工作状态下定子、转子摩擦力/力矩的特殊要求,并利用有限元法对传感器进行了结构优化,设计了组合式二维传感器,该传感器的一维测量法向正压力;另一维测量扭矩。法向力的量程为0~200N,准确度为0.09%;扭矩的量程为0~2N.m,准确度为0.41%。满足了试验要求。     

Piezoelectric linear motor with unimorph structure by co-extrusion process

A new piezoelectric linear motor was developed using a ring-shaped, unimorph stator composed of a piezoelectric active layer (0.3PZN–0.7PZT/Mn) and a conductive passive layer (0.3PZN–0.7PZT/Mn/Ag). The stator was prepared by co-extrusion followed by the thermoplastic green machining (TGM) process. After co-extruding the piezoelectrically active and passive layers together, they were machined into a ring shape and then sintered at 930 °C for 4 h. The stator was poled in the thickness direction and operated in radial vibration mode. A glass rod was used as the moving shaft. When a saw-tooth electric field was applied, the shaft moved linearly as a result of the stator's bending motion. When an inverted saw-tooth electric potential was applied, the shaft moved linearly in the opposite direction. The velocity of the piezoelectric linear motor was about 4 mm/s at an applied voltage of 80 V_p–p and a resonance frequency of 36.5 kHz.     

Resonant-Type Smooth Impact Drive Mechanism Actuator with Two Langevin Transducers

A smooth impact drive mechanism (SIDM) is a unique piezoelectric actuator that is widely used as a camera focusing mechanism, cell phone lens movement mechanism, etc. This principle enables a compact driving mechanism; however, it cannot generate high-speed movement because a soft-type multilayered piezoelectric transducer (PZT) is utilized at off-resonant movement. This paper proposes a resonant-type SIDM actuator driven with hard-type PZTs to realize high-speed and powerful operation. The fundamental principle is also based on the conventional SIDM; therefore, a saw-shaped movement is required. To generate a high-power ultrasonic output, two Langevin transducers are adopted instead of a soft-type multilayered PZT. One Langevin transducer was a stator and the other was slider whose tip was adhered to a carbon fiber reinforced plastic (CFRP) rod. The CFRP rod was connected to the stator transducer with the frictional force. To obtain quasi-saw-shaped vibration, the longitudinal vibration for each Langevin transducer was excited and these movements were added at the connection point at the CFRP rod. In order to combine these vibration modes, the lengths of the stator and slider Langevin transducers were designed to make the resonant frequencies ratio to be 1:2. By using the proposed principle, the slider Langevin transducer was successfully driven with the speed of 0.11 m/s and the output force was 1.8 N with no load.     

超声电机定子的动力学特性仿真

将行波超声电机的两相振动简化为两自由度系统,建立了基于模态假定的动力学方程,基于机电类比建立定子系统的传递函数技导纳表达式,通过有限元计算及实验测量确定模型参数,在此基础上建立了定子动力学模型的仿真模型结果表明该模型可用于进行定子的参数化设计及性能的预测。     

大范围纳米驱动定位压电马达的研究

提出一种基于尺蠖运动(Inchwormmotion)原理的大范围纳米级驱动压电马达,并着重阐述了压电马达的机械结构设计和控制系统的驱动电源等方面的内容。     

超声电机速度的模糊跟踪控制

与传统的电磁感应电机不同,超声电机是利用压电陶瓷的逆压电效应激发超声振动,然后通过定子和转子之间的摩擦作用把电能转化为机械能的一种新型电机.针对超声电机的非线性、难以建立精确数学模型等特性,以目前得到广泛应用的一类超声电机为研究对象,利用模糊T-S模型建立了超声电机的模型,基于此模型,结合模糊状态反馈控制和H<,∞>控...     

Study and optimization of traveling wave generation in finite-length beams

This paper presents a detailed study of the generation of traveling waves in finite-length beams. The method used is the mode superposition. It consists in exciting, with two actuators, two standing waves space shifted of a quarter wavelength and time shifted of a quarter period. Thanks to an analytical model giving the general solution of the flexural wave, we define the ideal conditions ensuring the best quality of this wave across the beam. Then, through an optimization process, we get the excitation parameters, actuator positions and driving frequency, that allow to approach at most these conditions.     

感应电动机调速系统的自适应逆控制

针对电压源型逆变器供电的感应电动机调速系统,提出了一种自适应逆控制方法,实现了电磁转矩和定子磁链的解耦控制．应用得到的逆系统将多变量、非线性、强耦合的感应电动机调速系统解耦为电磁转矩和定子磁链两个一阶线性子系统,从而简化了各个闭环线性调节器的设计难度．为了提高系统的鲁棒性,利用递推最小二乘算法实时辨识电动机参数,降低了参数变化对系统性能的影响．使用MATLAB软件进行了仿真实验,实验结果验证了理论分析的正确性和控制方案的可行性．     

The transfer function of a new disc-type ultrasonic motor

This paper deals with the transfer functions of a new disc-type ultrasonic motor: stator and stator–rotor energy transformation. The objective is to initiate a mode that can produce certain relative dynamic responses in the proposed motor. The performance will be parameterized by system inputs in an attempt to obtain an optimal operational configuration. The transfer function model of the piezoelectric ultrasonic stator based on the lateral elliptical motion is derived for the control application and certification of its load-characteristic parameters and also predicts the motor performance. On this basis, we can determine whether the output of the motor will be stable. The contact-dynamics behaviors of the stator are also studied. These derived formulations in this paper are based on the general concept of the constitutive laws governing piezoelectric materials which permit the introduction of kinetic energy, electrical energy, and geometric constraints relating to the deformation variables.     

小型超声导波管道检测系统的研究和开发

针对目前我国超声导波检测设备的落后现状,根据超声导波检测的机理,采用新型高速单片机、模数转换芯片、高频线性功率放大电路、环状阵列压电陶瓷传感器和基于LabVIEW的数据采集软件,开发了一种集成化的小型超声导波检测系统.该系统能够在管道中激励和接收超声导波,通过对激励波及反射回波的时空位置分析,判断出管道长度及存在的缺陷.     

Design Optimization of a Bionic Fish with Multi-Joint Fin Rays

This paper aims to design a novel bionic fish propelled by oscillating paired pectoral fins. Flapping motion deformation of the nature sample, the cow-nosed ray, is realized with simple mechanical structure through optimization. Locomotion analysis of the nature sample under linear cruise swimming conditions is carried out. Simplified mathematical models of the pectoral fin are obtained to be the design foundation of the bionic fin rays and the bionic fish. The number of fin rays is decided according to the passing kinematic wave shape and number. Distance and structure parameters are optimized, and determined by the minimum area error method. A novel two-stage slide–rocker mechanism is designed to fulfill the driving requirements with only one servo motor. System design of a new bionic fish robot is presented, including the mechanical design and the control method. Main bionic characteristics extracted from the cow-nosed ray are fulfilled by the prototype and verified by experiments.     

Effect of shearing deformation on the transient response of a traveling wave ultrasonic motor

Some works take into account the shearing deformation of frictional material, but its effect on the transient response has not yet been considered. In this paper, optimal deformation angle and resonance frequency of frictional material are investigated. Force expressions in the stator/rotor interface are developed. Mechanical characteristics taking into account the effect of shearing deformation are deduced and presented. It is shown that the shearing deformation affects the initial state as well as on the steady state. Also, the fast time response of the motor is deduced. Results of the simulation are validated using the measurements made by other researchers on traveling wave piezoelectric motor AWM90-X, Daimler-Benz type, and a prototype USM(AWM-90).     

步进电动机的最佳细分控制

提出按照线性加工弦规律波形对步进电动机绕组电流进行细分，以解决在实际应用中存在的低频振荡、高频出力不足、频率特性差等问题。设计制作了同频脉宽调制细分驱动电路。试验结果表明该方法是正确和可行的。