磁致伸缩位移传感器应用研究

主要阐述磁致伸缩位移传感器的测量机理,介绍了磁致伸缩位移传感器工作原理,重点讨论了影响磁致位移传感器测量精度的指标,并提出了应对措施。     

磁致伸缩位移传感器的研制

磁致伸缩位移传感器是基于磁致伸缩效应原理实现位移测量的器件，由于磁致伸缩材质和扭转渡的传播特性，以及电子测量电路对于精确测时功能的实现，使得该传感器同时具有非接触、绝对式测量、精度高、测量大位移、寿命长、安装简便，适用范围广等优点。且受外界干扰小，能在恶劣的环境下工作，已在国外得到广泛应用，而国内还没有自主研发的产品。文中介绍了自主研发的磁致伸缩位移传感器的工作原理，传感器的电路部分设计，以及该传感器的相关性能测试和测试结果分析，最后给出了一些性能提升的方案。     

磁致伸缩位移传感器检测信号分析

实验研究了磁致伸缩位移传感器的探测电压信号,以便提高磁致伸缩位移传感器的检测精度。分析和验证了波导丝材料、驱动脉冲电流、检测线圈等参数对磁致伸缩位移传感器输出电压的影响规律。对检测线圈进行了优化设计,基于实验数据确定了传感器的各项参数值。实验发现磁致伸缩系数大、魏德曼效应显著的Fe-Ga材料作为波导丝,可明显提高电-磁-机械能的转换效率,获得较大的检测电压信号。研制了新型Fe-Ga波导丝磁致伸缩位移传感器样机,并与Fe-Ni波导丝传感器进行了性能对比。结果表明,与Fe-Ni波导丝相比,Fe-Ga波导丝磁致伸缩位移传感器的检测信号明显增强,信噪比显著提高,其检测电压信号幅值比Fe-Ni波导丝检测电压信号幅值提高了40mV,相应的传感器精度提高了2倍。     

基于单片机的磁致伸缩位移传感器数字化处理系统研究

介绍了磁致伸缩位移传感器的结构、工作原理及信号特点，提出了一种小型数字化处理系统，利用单片机对磁致伸缩位移传感器的输出模拟信号进行数字化处理，采用轴取被测信号特征量的滑动滤波算法，得到准确的数字信号，以异步串行通信方式传输，提高了传感器的整体性能，使传感器更具智能化。     

磁致位移传感器及其应用

磁致伸缩位移传感器用非接触技术监控活动磁铁。由于磁铁和传感器并无直接接触,因此传感器即使在恶劣的工业环境下,例如易受油渍、溶液、尘埃或其它的污染,也能正常的工作。此外还能承受高温、高压、高振荡的环境,适用于多种不同的自动化环境,例如机械控制、木材加工和液体容积测量等。     

应用磁致伸缩现象的液压气缸位移传感器

应用磁致伸缩现象的液压（气）缸位移传感器于亚非随着工业自动化的不断发展，对液压（气）缸的位移检测要求越来越高了。在此介绍一种磁致伸缩式位移传感器，它具有高精度、高分辨率及高可靠性等特点，能进行模拟输出和数字输出，与计算机有良好的相容性。１工作原理磁致...     

超磁致伸缩微位移给进器异形板弹簧有限元分析

超磁致伸缩微位移给进器是以超磁致伸缩材料为核心、以自动控制理论为基础典型的机电产品。主要通过超磁致伸缩致动元件和微位移传感器实现闭环控制系统，并在软件上实现对磁致伸缩滞后等因素进行补偿，完成车刀的精密给进。根据内燃机活塞异形加工的要求，对超磁致伸缩微位移给进器的关键部件-异形板弹簧进行了有限元分析。通过有限元的计算结果发现，该异形板弹簧的最大应力值出现在弹簧的螺栓孔处，最大变形位置为顶端。这在设计时必须加以考虑。     

一种新型非接触式的传感器──磁致伸缩效应大位移传感器

本文对磁致伸缩效应位移传感器的工作原理作了详细的介绍。同时，对其电路部分也作了具体的分析，并给出了其主要的技术指标和应用场合     

基于SSI的磁致伸缩位移传感器测量系统的设计

设计了一种基于SSI的磁致伸缩位移传感器测量系统,重点介绍了测量系统的硬件设计和SSI接口时序。采用SSI接口作为磁致伸缩位移传感器的输出方式,通过FPGA综合管理和时序设计实现多路SSI信号的测量,并可以通过PCI总线传输接口实现FPGA与上位机的数据通信。测试结果表明,该设计方案稳定、可靠,满足测量系统性能指标要求。     

基于磁致伸缩逆效应的超磁致伸缩力传感器

磁致伸缩逆效应是稀土超磁致伸缩材料的一个重要应用特性,应用磁致伸缩逆效应可以制作超磁致伸缩力传感器。但由于缺乏相应的设计理论分析,从而制约了其发展。在分析了磁致伸缩逆效应的基础上,给出了超磁致伸缩力传感器的设计原理,设计了超磁致伸缩力传感器的结构,并采用数值计算方法对其磁场进行了计算。计算结果与实验结果的比较表明:二者符合较好,设计的超磁致伸缩力传感器方案是可行的,对其今后进行深入应用研究和优化设计具有重要意义。     

Effects of dissipative forces on Coriolis flowmeter readings

An indirect measurement method based on recording the phase difference of resonance vibrations of two symmetrical halves of the flow-carrying tube is used to quantify the mass flow rate of the current fluid in Coriolis mass flowmeters (CMFs). A variant of modeling the CMF vibration system is analyzed, which allows taking into account the influence of the dissipation of oscillations of a measuring tube with fluid flowing through it on the dependence between the mass flow rate of the fluid and the phase difference recorded by the sensor. The steady-state CMF vibration mode is considered as the result of the superposition of two principal vibrations of the measuring tube. The first principal coordinate corresponds to the deformation of the measuring tube along the lowest natural mode excited by an external driving force in the resonance mode. Vibrations of the other principal coordinate correspond to deformation in a natural mode corresponding to a higher natural frequency than the frequency of the exciting force. The relationship of the amplitudes of the principal coordinates is established on the basis of the gyroscopic coupling of the principal vibrations that occurs when a fluid flows through a tube. The coefficients of gyroscopic coupling are determined as a result of 3D finite-element simulation of the steady-state vibration mode of the measuring tube with a flowing fluid. The simulation is performed for five variants of the shape of the axis of the measuring tube, taking into account the distribution of the gyroscopic forces of the flowing fluid. Quantitative estimates of the influence of dissipative forces on the flowmeter readings are obtained on the example of dissipative forces of linear viscous friction. A comparison of the CMF simulation results for different tube axis shapes demonstrates how the phase shift arising in the vibration system is affected by the dissipation level and the proximity of the natural frequencies of the flowmeter measuring tube at a fixed mass flow rate of the fluid.     

应用系统重构技术提高空对地制导武器的作战效能

在阐述某型空对地导弹综合控制计算机和舵机系统的工作原理和技术要求的基础上,针对综合控制计算机初始化过程中舵控信号输出异常的现象,对综合控制计算机D/A转换芯片的特性和工作机理进行了深入的研究,详细阐明了舵控制信号榆出异常的原因,井给出D/A转换芯片的设计和使用是正常的和此类异常现象不属于故障的结论。     

基于自组装成品率的球栅阵列焊点工艺参数分析

为了提高球栅阵列焊点封装器件的自组装成品率,研究了焊点体积偏差率及焊盘直径对器件自组装成品率的影响。考虑封装器件的温度翘曲变形、焊点体积的不可避免的制造误差及焊点位置的随机性,分析了器件自组装过程。通过求解不同体积焊点的形态,得到了不同体积焊点的液桥刚度曲线。基于不同体积焊点的液桥刚度曲线,仿真分析了焊点体积偏差率及焊盘直径对器件自组装成品率的影响。结果表明,焊点体积偏差率及焊盘直径的减小会增大焊点液桥刚度曲线的公共范围,从而提高器件的自组装成品率。     

新型卡板式外径千分表的设计应用

针对机车牵引电机转轴磨削测量中,对转轴轴承位尺寸超差的原因进行分析,设计制作机车牵引电机转轴新型卡板式外径千分表(实用新型:ZL201420477030.7)。实际应用表明,新型卡板式外径千分表保证了牵引电机转轴轴承位的磨削尺寸,避免了转轴轴承位尺寸超差现象,解决了机车牵引电机转轴轴承位磨削测量的工艺、质量问题。     

A technique for recording and analyzing the isothermal relaxation of the capacitance of semiconductor heterostructures

A technique for recording and processing the results of measuring the isothermal relaxation of the capacitance that allows determination of the parameters of the charge-localization centers in semiconductor heterostructures is described. The experimental setup employed ensures recording of the dependences of the structure capacitance on the relaxation time within a wide temperature range. The obtained data are recorded into the computer memory. By choosing the parameters of recording of the capacitance relaxation and the parameters of the subsequent processing of experimental data within the framework of the deep4evel transient spectroscopy technique, it is possible, when determining the parameters of the charge localization centers, to reduce the effects from superposition of the peaks corresponding to the centers with close values of the emission time constant. The results of studying the activation energy of deep centers in the subsurface region of gallium arsenide are presented to illustrate the capabilities of the setup and technique developed.     

韧性材料的几种断裂形式及判据讨论

考察几种韧性材料的复合型断裂试验过程，用传统强度理论思想认定启裂位置与启裂方向，通过对不同物理机制的断裂形式变化规律的研究，判定韧性材料的主要断裂形式有三类，以空穴成核、扩张、聚合为主导机制的正拉断，和以局部剪切带形成、发展为主导机制的两种不同类型的剪切断裂。局部大塑性变形的出现在材料内引起损伤，空穴的聚合或局部剪切带的出现仅发生在载荷达到某一临界值时。导致材料断裂发生的根本因素，是危险点上某应力参数达到了材料的断裂临界值，以此对不同断裂形式的断裂判据进行讨论，提出新的韧性断裂判据。     

Changes in echo-pulse instantaneous frequency when scanning the transducer

A theoretical model has been proposed that makes it possible to explain peculiarities in the frequency characteristics of echo signals at the output of a receiving transducer depending on the geometrical parameters of a reflecting spherical surface when the transducer axis is displaced with respect to the surface’s center of curvature, that is, during scanning. It has been demonstrated that both with and without displacement of the transducer’s geometrical axis with respect to the center of curvature of the reflecting surface, the type of changes in the temporal dependences of the instantaneous frequency of signals at the output of the receiving transducer essentially depends on the geometrical parameters of a wavefront reflected from the surface: the smaller the radius of wavefront curvature at the aperture of the receiving transducer, the stronger the changes of the instantaneous frequency in the echo pulse. It has also been shown that the larger the curvature of this surface, the stronger the changes in the frequency characteristics of the echo pulse as the transducer axis is displaced with respect to the center of curvature of the reflecting spherical surface.     

高速动车组减振器载荷特征研究

减振器的主要功能是提供阻尼力以衰减和抑制车辆系统振动,对高速动车组动力性能有十分重要的影响。既有研究主要将减振器处理为阻尼力以研究车辆系统动力性能,极少从动力学和结构可靠性角度关注减振器自身承受的载荷。制作某型高速动车组转向架抗蛇行减振器、轴箱减振器、二系横向和垂向减振器测力元件,在大同-西安高速线路上测试并获得该型动车组运行过程中四种减振器载荷引起的应变信号。对测试数据进行处理和分析,获得高速动车组运行工况下四种减振器载荷的时间历程,分析减振器载荷的时域和频域特征。采用雨流计数法统计减振器载荷峰谷值和频次,获得不同速度等级下载荷分布。结果表明,高速动车组抗蛇行减振器载荷最大、二系横向减振器载荷最小。轴箱减振器相对速度最大、二系横向减振器相对速度最小。减振器载荷总体上呈正态分布,而且一般有列车运行速度越高减振器载荷越大。列车正线行驶时曲线半径对轴箱减振器、二系垂向减振器以及二系横向减振器载荷影响不明显,列车速度和线路小半径曲线对抗蛇行减振器载荷影响明显。     

The dynamic stability of a crane standing on soil during the rotation of the boom

In this work the influence of flexible soil foundation on the dynamic stability of the boom crane is presented. This analysis was made during the rotation of the boom, such that variable pressure on the soil and other deformations could be taken into account. The rheological deformation of the soil as a function of the changing strain in time has been described by an equation, which is the Duhamel integral. After accepting the discrete model of the considered system dynamic equations of motion were elaborated, which because of their nonlinearity and complexity were solved numerically. Appointed were the dynamic displacements of each of the supports for different rotational speeds of the boom, showing the influence of the rheological deformation of the soil on the behaviour of the whole crane. As well the trajectories of the motion of the weight hoisted were presented for different rotational speeds of the boom, which enabled the analysis of the precision of the positioning of the weight being hoisted (minimization of oscillation).     

RV减速器摆线轮齿廓曲线的曲率影响因素研究

以工业机器人为例,对RV减速器摆线轮齿廓曲线的曲率的影响因素进行了研究。根据微分几何理论,建立摆线轮齿廓的数学模型,采用坐标变换方法推导出摆线齿廓方程,分析了摆线轮齿廓曲线的凹凸特性,求出拐点的数学解析式。根据摆线齿廓方程计算出曲率和曲率半径的参数表达式,最后推导出可以概括摆线针轮传动的诱导法曲率公式。以RV-20E减速器为例,求解出凹凸区间曲率最大值和最小值,并利用Matlab编制程序进行仿真,详细分析了机构的偏心距、针齿半径、针齿分布圆半径、针齿数对拐点所在位置、曲率变化快慢的影响规律。通过对摆线齿廓的曲率的仿真分析,偏心距和针齿分布圆半径对摆线齿廓的曲率影响显著,同时也会影响拐点位置的变化,针齿半径对其有一定的影响,但影响较小,并且不会影响拐点所在的位置。研究结果为科学地选择摆线轮最佳参数和摆线针轮传动的设计提供了一种理论依据,具有一定的实用价值。