负荷传感技术在重型平板车液压控制系统上的应用

近年来,负荷传感液压系统作为一种先进的液压技术在重型平板车上展现了其应用趋势.在介绍了变量泵负荷传感系统原理的基础上,针对某型号重型平板车的工艺要求,设计开发了具有节能、高效和可控性能高的转向与悬挂液压控制系统.     

基于Bandelet稀疏的移动机器人环境视觉纹理图像的压缩传感与重构

压缩传感技术为移动机器人环境视觉的实时高效处理与传输提供了一种新的解决方法。结合Bandelet变换自适应跟踪图像正则方向的特点,进行了基于Bandelet稀疏和正交匹配追踪(OMP)算法的环境纹理图像压缩传感重构分析研究。结果表明：在较大观测值下,Bandelet稀疏重构与传统小波稀疏重构效果差别不大;在较小观测值下,传统sym8小波稀疏重构出现不稳定状态,出现块状信息缺失,不能有效重构,而Bandelet稀疏重构效果相对稳定;在给定观测值下,Bandelet稀疏重构的边缘细节表达能力优于sym8小波,说明Bandelet变换在压缩传感采样高压缩比下恢复重构具有有效性和稳定性。     

无线传感网络的传输信道低误码率控制模型

为了提高无线传感网络通信的信号调度和无损传输能力,提出一种基于波特间隔均衡的通信信道均衡传输控制模型,结合传输信道均衡算法进行无线传感网络通信性能的优化设计,构建无线传感网络通信的信道模型,采用码间干扰抑制方法进行无线传感网络通信的信号传输抗干扰设计,采用直接序列扩频和波特间隔均衡控制技术进行无线传感网络通信的信号传输和自适应调度,构建无线传感网络传输信号的信道均衡控制模型,进行无线传感网络传输信号传感融合识别,实现对无线传感网络通信网络的通信信道均衡处理。     

基于视觉的机器人智能化焊接技术现状与发展

针对机器人自动焊接技术快速发展的现状,结合机器视觉技术、智能控制技术和信息技术在焊接技术领域应用的特点,归纳综合了弧焊视觉传感技术、激光接缝跟踪技术、熔池视觉形态特征传感与提取技术、熔透与熔深智能控制技术、缺陷监测及控制技术和基于网络的数字化焊接技术的研究现状,分析了激光跟踪传感器结构、熔池与接缝计算机图像处理方法、熔池视觉几何特征提取方法、熔深熔透视觉传感与判断技术、基于网络的焊接信息远程传输与品质评价技术,给出了弧焊机器人智能化和数字化焊接技术优质、高效、柔性、快速、适应性强的特点,探讨了的智能化、数字化焊接技术的主要发展方向。     

条码传感技术在小型物流自控系统中的应用

本文介绍了在由传送辊道、分拣机械手、立体仓库和堆垛机组成小型物流自动控制系统中传感技术的应用,主要介绍了在控制系统中采用VS800条码传感器实现物料的自动分拣,并通过对条码信息的数据采集、传输、处理实现物料出、入库的自动控制与信息管理.     

电能表数据传感器的设计

电能表数据传感器是一种通过机电变换方式将电磁式电能表的待记录数据转换为电脉冲信号的传感装置,主要功用是进行数据远程传输和电子显示,主要介绍电能表数据传感器的组成和工作原理,重点介绍电能表数据传感器的结构和运作过程。     

量子隧穿纤维的制备及其传感特性研究

介绍一种功能性纤维,它是用于感知外界微振动、微变形或是声波传输的传感纤维,因其运用隧道电流效应原理,故将其命名为量子隧穿纤维(QTF,quantum tunneling fibre),并对其传感特性做了初步研究,取得了一定的成果。通过不同方法制备出较优的纤维,搭建悬臂梁应变实验及振动实验。实验结果表明:量子隧穿纤维具有较高的静态及动态传感性能。     

长周期光纤光栅及其在通信传感领域的新应用

长周期光纤光栅是一种新型光纤器件。介绍了长周期光纤光栅的耦合机理、制备方法以及应用。其耦合机理是前向传输的纤芯基模与前向传输的各阶包层模式之间的耦合。制备原理是对光纤横向曝光,使光纤的折射率指数在轴向发生周期性变化。阐明了长周期光纤光栅用于带通滤波、光上下路复用、光纤光源、光纤耦合、偏振器件、新型传感等新技术领域的思路,给出了具体实现方法。并通过与其他方案对比,说明了基于长周期光纤光栅器件的优点,肯定了长周期光纤光栅在通信传感领域的价值。     

利用 Wi-Fi 信道的超低功耗无线传感系统

现有的无线传感系统的传感节点需要主动发射射频电磁波进行数据传输,功耗高;利用反向散射调制的无源无线传感系统需要高成本专用阅读器,应用受限。针对上述问题,本文提出利用Wi-Fi信道的无线传感系统,用反向散射调制将传感数据调制于Wi-Fi设备发射的信号中,影响Wi-Fi信道参数。使用Wi-Fi接收设备获取信道状态信息,通过支持向量机训练识别传感数据的检测器,实现无需专用阅读器的超低功耗无线传感系统。用路由器、无线网卡、传感节点搭建无线温度传感系统,传感节点最高功耗不超过350μW,安装无线网卡的Wi-Fi接收设备可读取传感节点距路由器5 m内,以200 bit/s速率传输的传感数据。该系统为智能家居、可穿戴设备等应用的超低功耗无线传感需求提供了有效解决方案。     

皮带机沿线光纤测温装置测温技术分析及安装研究

针对矿用皮带输送机具有托辊数量多,难运维的特点,基于光纤测温原理,通过应用光纤传感技术,来及时高效地监测皮带机托辊温度,介绍了光纤传感技术及其主要优势,分析了测温系统的组成及其具体工作原理,通过比较几种光纤安装方案,得到了最合理的光纤安装方案,皮带机光纤测温装置的应用,减轻了皮带机运维量,实现了皮带机运维的降本增效,达到了高效运维皮带机的目的 .     

Goubau Ice Sensor Transitions for Electric Power Lines

In this paper, 50 Ohm coaxial line transitions required for sensing dielectric (or ice) coatings on power transmission lines (Goubau lines) at microwave frequencies (below 10 GHz) are proposed, designed and simulated. Two different types of transitions are needed: uni- and bi-directional. Computer simulations are performed using finite element methods (FEM). Good performance results using both types of microwave transitions are obtained. Design and simulation results show that Goubau line type transitions can be realized for various applications including detection of ice layers and microwave communications on electric power transmission lines.     

On the Measurement of Thickness of Ice Layers on Power Transmission Lines

In this paper, measurement of ice and ice/water layer thickness on power transmission lines using Goubau modes at 1, 2.54 and 10 GHz is analyzed, simulated and discussed. Ice layer thicknesses change the phase and attenuation of Goubau mode propagation over a given line length. It is found feasible to determine layer thickness by measuring the phase and attenuation of the Goubau mode at a few GHz. In addition to the thickness, it is also possible, to determine the composition of the layer by measuring the different dielectric properties of ice, water and their mixture over a wide bandwidth to develop a database for comparison with measured data. The sensitivity of suggested instrumentation is sufficient for short line lengths (up to 1 m) or long lengths (several km). The implementation of instrumentation on long lines is still to be done but no major obstacles are foreseen. The decision to de-ice transmission line using any given and established techniques is facilitated if average ice thickness on transmission line between supporting transmission line towers can be measured.     

一种基于SIW的阶梯式太赫兹宽带传输线

提出了一种适用于太赫兹频段、长距离传输的阶梯式宽带传输线.将2个基片集成波导(substrate integrated waveguide,SIW)分别置于一个矩形波导两端并分别呈直角转接,整个结构组成一级阶梯形状以实现波导口的空间位置平移.通过在矩形波导两端使用耦合窗的方法完成空气与基片介质之间无模式转换的转接.所提...     

一种提高太赫兹波成像分辨力的方法

成像分辨力低是影响太赫兹波成像系统在质检、安全和医疗领域应用的重要因素之一。用返波管（BWO）作为太赫兹波辐射源搭建了一个连续太赫兹波点扫描透射成像系统。采用扫描步长小于系统聚焦光斑尺寸的方式获得样品物体的太赫兹透射图像,并利用增量维纳滤波法对该图像进行复原获得了超过系统衍射极限分辨力的太赫兹图像。实验结果表明该方法可以有效提高太赫兹波成像的空间分辨力。     

Modeling and characterization of a cantilever-based near-field scanning microwave impedance microscope

This paper presents a detailed modeling and characterization of a microfabricated cantilever-based scanning microwave probe with separated excitation and sensing electrodes. Using finite-element analysis, we model the tip-sample interaction as small impedance changes between the tip electrode and the ground at our working frequencies near 1 GHz. The equivalent lumped elements of the cantilever can be determined by transmission line simulation of the matching network, which routes the cantilever signals to 50 Omega feed lines. In the microwave electronics, the background common-mode signal is canceled before the amplifier stage so that high sensitivity (below 1 aF capacitance changes) is obtained. Experimental characterization of the microwave microscope was performed on ion-implanted Si wafers and patterned semiconductor samples. Pure electrical or topographical signals can be obtained from different reflection modes of the probe.     

太赫兹金属弹簧波导的研究

为深入了解金属弹簧波导对太赫兹波的传输效果,对不同螺线间距金属弹簧的太赫兹波传输特性进行了实验研究。实验结果表明,对于线径0.8 mm、外直径12 mm、长14 cm的金属弹簧,在3.5/4.4 mm等较大的螺距下,弹簧波导反而能在较大的带宽下传导太赫兹波,并具有良好的偏振保持能力。3.5/4.4 mm螺距弹簧的太赫兹传输带宽均约为0.9 THz,且在其峰值频率处的传输损耗分别约为0.2 cm-1和0.27 cm-1。此外,金属弹簧能将太赫兹模式束缚在空气芯内传输,而非通过金属螺线导引传输。该研究结果对金属弹簧波导在太赫兹技术中的应用具有一定参考意义。     

A new 1.4-GHz soil moisture sensor

Moisture content determination in agriculture and civil engineering is a common process which needs special sensors with high accuracy, durability and compatibility with the measurement environment. A new 1.4-GHz soil moisture sensor using microstrip transmission line is presented. The proposed sensor consists of two separate parts: (1) A sensor head, which is a microstrip transmission line to be placed in the soil, and (2) an electronic transceiver which sends a sinusoidal wave into the sensor head at one end of the transmission line, and receives the traveled wave from the other end. Transmitter is basically a Colpitts oscillator, and the receiver is a phase detector that measures the phase shift due to velocity variation caused by the moisture content of soil. At a certain frequency, the velocity of a microwave traveling through a media depends on the permittivity of that media. The proposed sensor is implemented and tested on one sample of typical soil. The main advantages of the proposed sensor are its high accuracy, quickness of measurement, its low cost and ease of implementation. Since the sensor has low power consumption, it can be recommended for low-power applications such as wireless sensor network.     

基于超表面的太赫兹复用成像

提出了一种基于单层超表面的太赫兹复用器件。该器件基于PB(back propagation)相位理论、广义斯涅耳定律以及马吕斯定律,实现了空间分复用成像。计算结果表明,所设计的器件能将一束线偏振入射光离轴出射,并产生多通道的复用图像。该器件的研究对拓展THz波段的高分辨成像、多通道信息传输等功能具有重要意义。     

Application of superlattice multipliers for high-resolution terahertz spectroscopy

Frequency multipliers based on superlattice (SL) devices as nonlinear elements have been developed as radiation sources for a terahertz (THz) laboratory spectrometer. Input frequencies of 100 and 250 GHz from backward wave oscillators have been multiplied up to the 11th harmonic, producing usable frequencies up to 2.7 THz. Even at these high frequencies the output power is sufficient for laboratory spectroscopy. Comparisons to conventional high-resolution microwave spectroscopy methods reveal several superior features of this new device such as very high line frequency accuracies, broadband tunability, high output power levels at odd harmonics of the input frequency up to high orders, and a robust applicability.     

基于DSP的中药丸料湿度密度在线检测系统

设计与研制一种能在现代化中药制药生产线上在线连续测量中药丸料湿度与密度的微波检测系统。系统包括三个组成模块：微波信号源模块，微波谐振腔，数据处理模块。其中，微波谐振腔是专门设计用于中药丸料湿度与密度检测的中心开通孔的金属谐振腔，当中药丸料通过微波谐振腔的中孔时，丸料密度及湿度均令谐振腔的谐振频率产生偏移和功率衰减，数据处理模块据此计算中药丸料的湿度与密度。为提高检测精度，采用模糊聚类算法对实验数据进行分组，对金属谐振腔的频偏和功率衰减特性进行建模，并利用DSP设计并实现了中药丸料湿度与密度的在线检测。现场调试表明：该检测系统适宜于现代化中药制药生产线上的湿度连续在线测量，其检测精度达到93％以上。