两种几何尺寸对落锤冲击装置加速度激励的影响

微机电系统的不断发展使得加速度传感器被广泛地应用于机械、航空、航天等各领域。加速度传感器的精确校准是其设计制造中的重要一环。落锤冲击装置是常见的加速度计校准系统中的信号输入装置,落锤几何尺寸的改变直接影响着加速度传感器的校准精度。文章基于有限元分析软件ABAQUS对落锤厚度与落锤碰撞面半径的尺寸大小对冲击加速度脉冲的影响进行了数值模拟研究。通过对数值模拟结果的分析得出了以上两种因素对加速度峰值和脉冲宽度的影响规律。不仅为落锤式冲击激励装置的优化提供了参考,也为优化加速度计校准方式提供了新的思路。     

连续物料输送机单片机称重装置设计

连续物料输送装置采用称重传感器测量物料重量，并以单片机作为称重装置计算和控制的核心元件，对传感器送来的信号进行必要的分析、控制、处理、驱动显示，实现在线动态检测；采用软件方法对传感器信号进行一定的处理，减少电路设计难度和元件性能在温、湿度等变化时对电路的影响。     

通用光栅数显装置的研制

为了实现光栅传感器的位移测量,文中研制了一台通用光栅传感器数显装置.该装置通过差分放大器、比较器对输出模拟信号的光栅传感器进行信号处理,与输出数字信号的光栅传感器共用位移测量系统.运用阵列逻辑GAL实现光栅信号的四细分和辨向,利用单片机对GAL输出的细分辨向信号进行计数,通过数码管实时显示光栅传感器的位移测量结果.通用光栅传感器数显装置的研制实现了对模拟/数字信号的测量功能,提高了通用性.     

基于绝对式准静态校准的测力传感器分析

在详细探讨了利用落锤装置进行压力校准的多种途径的基础上,对于力监测压力的绝对式准静态校准方法,若采用制式产品的测力传感器通过螺栓连接的方式固定于落锤装置时,在测力过程中会受到摩擦力、预紧力和惯性力等影响。为了精确测量锤头撞击精密活塞杆时力的大小,根据目前装置的结构及设计要求,研制了锤头及敏感元件一体化的高精度应变式测力传感器并对其进行理论计算和仿真分析,通过试验进一步研究测力传感器的静态特性和动态特性,最终通过试验验证了其可行性。     

四丁基溴化铵（TBAB）包络化合物浆（CHS）固相含量的电导率法测量研究

本文作者设计了一套四丁基溴化铵(TBAB)包络化合物浆(CHS)的固相含量测量装置,该装置通过圆弧电极和一个独创的微电极构成的传感器测量CHS两相流体的电阻率信号,经过采集、处理后得出CHS中的固相含量.开发出了相应测量的计算模型,针对正弦和方波不同频率的激励信号做出一系列实验并对实验结果进行理论分析,实验结果表明:测量在低于1.5 kHz的方波激励信号下有较好的表现,整个测量装置有较好的分辨率,可应用于CHS固液两相流固相含量的测量.     

基于落锤装置的力监测压力绝对校准方法研究

在详细探讨了利用落锤装置进行压力校准的多种途径的基础上,针对力监测压力方法中存在的传感器力值测量精度易受预紧力和惯性力影响的问题,提出了一种改进方法,即在落锤装置原有锤头结构的基础上自行研制了高精度的应变式力传感器,推导了通过自研力传感器监测造压油缸内压力的惯性力修正模型,并总结了模型进一步简化所需满足的前提条件。在此基础上分别对传统和自研力传感器开展了多组校准试验,试验结果表明,采用过渡件和螺栓固定等传统安装方式会对力传感器产生附加预紧力和惯性力两方面的不良影响,造成传感器在测量锤头和活塞杆之间的撞击力时产生很大的测试误差;自研力传感器在满足重锤质量远大于活塞杆质量并保证撞击对中精度的前提下,能够直接根据传感器测得的力值和活塞杆横截面积计算出缸内的压力,和现有的比对式准静态校准方法相比,其高压段压力监测精度优于1%,可作为一种有效的压力校准方法。     

专利信息

用于衡器的超薄型无过梁传感器;测量传感器输出信号的处理方法以及测力装置;负载传感器内置型重量计量装置;     

基于Multisim的电感传感器信号测量系统仿真

电感传感器具有抗干扰能力强、测量精度高等特点。通过建立信号发生电路、T形电感等效电路、放大电路、检波电路和滤波电路等构建电感传感器的信号检测处理系统。根据电磁感应原理，利用电感传感器等效电路中电感的变化代替测头探针移动，实现测量系统信号处理过程。使用Multisim 14.0软件对搭建的电感传感器输出信号处理电路进行仿真分析，得到直流电压信号；对仿真试验得到的数据进行曲线拟合，得出线圈电感变化与输出电压信号在一定情况下成正相关。试验结果表明，信号处理电路设计可靠，可以实现预期功能，对实际测量试验平台搭建具有重要意义。     

微位移检测系统中精密光电转换电路设计

基于像散原理的光学检测系统,是通过对光路系统聚焦信号的离焦量FES的检测实现微位移的测量.四象限光电探测器作为检测系统的光电转换传感器,需要设计光电探测器电路,实现对FES信号的检测,并由微单片机系统采集处理,通过串口通信传给PC机进行数据存储和被测对象二维图像分析和重建.通过将所设计的电路集成在光学测头装置上进行实验测量,光电转换信号稳定,相对误差小于5%.     

光纤位移传感器的研制与应用

讨论了通过控制实现位移的测量和显示，运用单片机作为中央处理器处理数据以及控制系统动作，采用随机型光纤位移传感器和半圆型光纤位移传感器，使用电子线路对光纤位移传感器的信号进行处理和线性补偿，扩大了传感器的测量范围。利用反射式光纤位移传感器的工作原理，通过对反射光强信号的检测，提出了一种用于轧辊磨损度在线非接触检测的光电检测法。     

汽轮发电机转子温度光纤测量系统性能研究

本文介绍了一种新颖的在线监测发电机转子表面温度的光纤测量系统，并对系统的各种性能进行了实验测试。结果表明，该系统具有结构简单，安装方便，性能可靠等优点，系统测温误差在±３℃左右。     

Estimation of uncorrelated content in experimentally measured frequency response functions using three measurement channels

Experimental frequency response functions (FRF) measurements are normally made by measuring two signals: the force applied to the structure and the resulting response. If the coherence between these signals is less than unity, it is known only that there is uncorrelated content present in either or both signals.This paper presents, for the first time, a method for estimating the magnitude and source of any uncorrelated content present in a measurement system, provided that the original random signal is available for measurement. This is the case when a signal generator/amplifier/shaker set-up is used. However, this method cannot be applied to hammer impact testing.Measurements are made of the signals from the random noise generator, the force gauge, and the response transducer. From these measurements estimates can be made of uncorrelated content in the force and response measurements as well as in the amplification/shaker system. These estimates of uncorrelated content will be useful in improving the measurement system and in determining when the results from the and estimators are valid. They also can be used to estimate the s² term in .The uncorrelated content estimators are applied in several different FRF measurements. Estimates of uncorrelated content from an inefficient non-linear shaker-to-force-gauge connection, from a ground-loop problem, and from leakage are shown. Limits on dynamic range are discussed.     

一种新的音频分析系统的实现方法

失真度是无线电信号测试的一个重要参数.提出一种以数字处理芯片DSP和MCU为基本结构,两路DDS芯片及幅值调节电路完成双音频信号发生,快速傅里叶变换来实现对正弦信号失真度的测量方法.DSP芯片为FFT算法提供的快速专用指令,使得程序在快速性和测量精确性方面有很大提高.上位机通过双口RAM完成对音频分析与信号发生模块的实时控制.实测结果表明,系统SINAD值测量准确度优于±0.3 dB、失真因素优于0.2%,可以有效的完成电子系统的综合测试并替代国外同类设备,满足实际应用需求.     

高频信号发生器设计及在水处理系统中的应用

高频信号发生器是高频水处理仪的核心部件，具有除垢抗垢杀菌的作用。本文以集成单片高频信号发生器MAX038为核心．设计了波形发生电路．频率测量电路和频率显示电路．能够输出频率和占空比可调高频方波，正弦波及三角波。     

窝点接触力自动测试仪数据采集系统的设计

实现了一种用于自动测量弹性臂窝点接触力的新型测试仪.主要介绍了该仪器数据采集系统的硬件和软件设计.其中硬件电路的设计包含了信号调理电路和信号采集电路,前端使用了仪用放大器调理传感器输出的微弱信号,后端使用了AVR单片机完成AD转换和数据串行传输.上位机软件主要负责仪器的运动控制、视觉测量和数据的采集和处理.软件的数据处理部分采用了Matlab6.5与VC6混合编程来实现窝点接触力的求解.     

Design and dynamic analysis of a pneumatic impulse generating device for the non-destructive testing of ground anchorages

This paper describes the design and dynamic analysis of an impulse-generating device which has been developed for use as part of a system to test ground anchorage systems non-destructively. The device is a relatively simple pneumatically operated design similar in function to a small air hammer working under computer control. An accelerometer attached to the device provides the measurement function. Results from the testing system are presented which show that in some cases the response of the anchorage to the input is a complex spectrum of frequencies. A dynamic model of the device, including the pneumatic system, is presented and results from this indicate that multiple impacts are occurring within the device during the measurement period. Analysis of the frequency spectrum of a two impulse force input is presented and using a single degree of freedom system and a previously developed and validated model of a ground anchorage, it is shown how the two impulses can produce the type of response exhibited by the test result from an anchorage. Some possible mechanical and signal processing solutions to mitigate the problem are presented.     

A phase stability control system in radiointerferometry experiments

A phase-stability control system of the radio-receiving section of a radio telescope, used in radiointerferometry observations, is presented. The system contains a picosecond pulse generator the phase of output pulses of which is synchronized with the reference-signal phase. The generator pulses with a 40-ps duration are applied to the input of the receiving unit, and, having passed the same path, as a signal received from celestial sources, are intended to compensate a signal-phase change occurring in the receiving-converting section by the correlation processing. The designed system controls the phase stability with an accuracy of 10 ps.     

Heterodyning based portable instrument for eddy currents non-destructive testing

The development and implementation of a portable eddy currents testing instrument with heterodyning based measurements is presented in this paper. The instrument is composed by a dedicated electronic measurement circuitry embedded inside a rugged tablet computer for control and visualization and that interfaces a small footprint planar eddy currents probe. A DDS waveform generator and a transconductance amplifier are used to drive the probe current. The probe output voltage is amplified up to 60 dB and down-converted to an intermediary frequency, which is then digitized. IQ demodulation of the digitized signal is used to obtain the real and imaginary components of the probe output and is computed in real time by the embedded digital signal processor and transmitted to the host computer by USB. The eddy currents testing instrument can be operated as a battery powered standalone device with post-processing and visualization capabilities which can be modified for specific applications without the need for hardware modifications. The system architecture, electrical characterization of the analog circuit, digital signal processing and visualization interface are described. The eddy currents inspection results of an aluminum sample with synthetic defects and friction stir welding joint samples, using this instrument are presented.     

基于PCI总线的小口径高压力电容层析成像系统

介绍了一种应用于高压力气体密相输送煤粉装置中的小口径电容层析成像系统.电容传感器采用8电极结构,交流法电容检测电路可以保证系统具有相当高的电容测量精度,引入带通滤波对信号进行预滤波,可有效提高信噪比.交流和直流两级增益可调,实现宽范围电容检测.硬件系统设计基于PCI数据总线结构,系统运行过程由计算机程序控制,便于后期的数据处理.同时也解决电容层析成像系统和计算机之间通信速度的问题,数据采集速度达300帧/秒.     

DSP技术在风力发电机组状态监测系统中的应用

数字信号处理器（Digital Signal Processor,DSP）具有强大的控制和信号处理功能,如今,广泛应用于军事,数字通信、工业测量及自动控制等要求实时性的领域,因此,DSP已发展成为数字化时代的核心元件。本文简要介绍了风力发电机组的状态监测系统,然后重点介绍了利用以DSP为核心的数据处理器对现场数据进行AD采样和时域状态参数计算。在此基础上提出了一些硬件和软件处理手段,证明可以有效的解决实际使用中采样精度低的问题,实现了一种可靠有效的数据采集处理系统。