A generic multielement microsystem for portable wirelessapplications

An open-architecture microsystem that can be populated with a variety of sensors and actuators is described. The microsystem is designed for low-power wireless applications where small size and high sensor accuracy are important. It consists of an in-module microcontroller connected to multiple front-end transducers through an intramodule sensor bus. An external interface allows internally processed data to be output through either a hard-wired input/output port or a radio-frequency transmitter. The present microsystem is configured for environmental monitoring and measured temperature, barometric pressure, relative humidity, and acceleration/vibration. It occupies less than 10 cc, consumes an average of 530 μW from 6 V, and transmits data up to 50 m. System features such as active power management, the intramodule sensor bus, generic bus interface circuitry, and in-module sensor compensation based on bivariate polynomials are discussed     

金属环封装低频光纤布拉格光栅振动传感系统研制

研制了一种金属环封装的单柱体芯轴式光纤布拉格光栅(FBG)振动传感器,搭建了基于非平衡迈克耳逊干涉仪相位载波调制(PGC)解调技术的FBG振动传感器解调系统,实现了低频振动信号的高精度实时解调,并分析了各参数对传感器谐振频率和灵敏度等特性的影响。实验结果表明,研制的FBG振动传感器谐振频率为388Hz,在10～200Hz频率范围内,传感器的加速度灵敏度约为81pm/g,且加速度响应平坦,起伏小于1dB,与理论分析结果基本一致。研制的振动传感器可实现200Hz以下低频振动信号的实时检测,解调系统的波长检测精度为1.07×10-3 pm,最小可检测加速度为1.3×10-5 g。     

压电加速度传感器有限元仿真方法研究

压电加速度传感器具有频带宽,结构简单,耐高温性能好等特点,在复杂机械应力和高温应力环境下应用广泛,是航空发动机健康监测、爆炸冲击监测等应用下必不可缺的器件。对于压电加速度传感器的设计和研究,常使用有限元仿真法来分析其固有频率、响应及在此基础上的各种机械应力、温度应力下的状态。从压电加速度传感器的原理、结构和有限元仿真的基本流程出发,调研了压电加速度传感器有限元仿真中的主要问题。按照不同结构类型总结了建立几何模型时的结构简化方法,分析了螺栓预紧力的主要仿真方法;区分部分仿真和整体仿真,总结了固有频率的仿真方法;按照不同激励,讨论了不同应力的仿真实现方法。     

机载传感器加速度状态下可靠性检测系统研究

针对机载传感器加速度状态下性能检测问题,设计并实现了一种机载传感器不同加速度状态下可靠性检测系统。该系统基于离心运动提供加速度原理和RS485通信技术,设计并实现了离心机数据采集系统。实验结果表明,设计的离心机实验平台可靠稳定,能够实现飞机加速度模拟,以及在0-10G不同加速度条件下的传感器输出信号高速采样检测,传感器标准样本临界状态检测准确率达到100%,有效保证传感器在飞机运行过程中的正常工作。     

基于嵌入式的厂区环境在线监测系统的设计

目前结合Zigbee无线传感网络和嵌入式技术的实际应用层出不穷,通过使用Zigbee无线传感技术,方便地实现信息的智能获取与系统管理。系统基于CC2530模块为控制核心的前端数据采集节点,利用CC2530搭载GP2Y1010粉尘传感器、二路光耦测速传感器、DHT22温湿度传感器、BMP180气压传感器实现对数据的实时采集、处理。同时利用CC2530射频单元搭建Zigbee网络,实现数据的无线传输与共享。树莓派上位机界面通过串口触摸控制整个系统,系统完成一次数据通信转接板指示灯闪烁一次,提高了控制平台的便携性和数据通信的可检验性。最终进行系统现场实测,设计既可以实现低功耗数据采集,又可以实现树莓派对数据的实时监测和处理,整体设计确保生产生活安全、经济、有效、健康地进行。     

基于无线传感器网络的角度监测系统

针对传统的角度测量设备体积庞大,测量精度低,实时性差等问题,介绍了一种空间物体三维姿态监测系统,其使用三轴加速度传感器监测空间物体的横摆角和俯仰角,使用三轴地磁传感器,结合加速度传感器对其进行修正,监测空间物体的滚转角,监测数据通过Zigbee无线通信网络传输至监测终端进行数据的实时显示与存储.测试实验证明系统具有使用灵活、测量精度高,实时性好等优点.     

Simple low-frequency optical fiber accelerometer with largerotating machine monitoring applications

A simple fiber optic accelerometer with large rotating equipment monitoring applications is presented. The sensor is optimized for detection of mechanical vibrations in the frequency range 0.2-140 Hz. The minimum detectable acceleration is 0.025 m/s² root mean square (rms), and it has low transverse sensitivity. The transducer operating principle, based on a fiber optic cantilever beam without any selamic mass on it, is simple and easy to construct, and the intensity-modulation and compensation techniques developed require simple electronic processing and provide very good stability and accuracy. Other advantages of the system are its robustness, compact size, and cost-effectiveness, which make it appropriate for industrial applications, specially for those where harsh environments are involved. The complete process of research and development of the sensor has been carried out, from the theoretical study of its operation principles, through the design, fabrication, experimental characterization and enhancement, to its starting up in a high-power electric station for hydrogenerator monitoring     

基于ZigBee无线网络的电源电压监控系统

针对当前传感器网络普遍采用的有线连接方式的布线不便、灵活性不高的缺点,提出了一种基于ZigBee无线网络的实时监控系统的实现方法。介绍了利用CC2430芯片搭建系统硬件平台的方法和各节点协议栈的软件设计过程,最后介绍了使用LabWindows/CVI制作上位机界面。最终实现了利用无线网络对电源的监控。实验证明,该系统能够采集ZigBee无线传感器网络内节点的电源电压即时数据。     

Microchannel‐Confined MXene Based Flexible Piezoresistive Multifunctional Micro‐Force Sensor

Multifunctional micro‐force sensing in one device is an urgent need for the higher integration of the smaller flexible electronic device toward wearable health‐monitoring equipment, intelligent robotics, and efficient human–machine interface. Herein, a novel microchannel‐confined MXene‐based flexible piezoresistive sensor is demonstrated to simultaneously achieve multi‐types micro‐force sensing of pressure, sound, and acceleration. Benefiting from the synergistically confined effect of the fingerprint‐microstructured channel and the accordion‐microstructured MXene materials, the as‐designed sensor remarkably endows a low detection limit of 9 Pa, a high sensitivity of 99.5 kPa^?1, and a fast response time of 4 ms, as well as non‐attenuating durability over 10 000 cycles. Moreover, the fabricated sensor is multifunctionally capable of sensing sounds, micromotion, and acceleration in one device. Evidently, such a multifunctional sensing characteristic can highlight the bright prospect of the microchannel‐confined MXene‐based micro‐force sensor for the higher integration of flexible electronics.     

Design and Development of Thermistor based Power Meter at 140 GHz Frequency Band

Design and development of thermistor based power meter at 140 gigahertz (GHz) frequency band have been presented. Power meter comprises power sensor, amplifier circuit and dialog based graphical user interface in visual C++ for the average power measurement. The output power level of a component or system is very critical design factor. Thus there was a need of a power meter for the development of millimeter wave components at 140 GHz frequency band. Power sensor has been designed and developed using NTC (Negative Temperature Coefficient) thermistors. The design aims at developing a direct, simple and inexpensive power meter that can be used to measure absolute power at 140 GHz frequency band. Due to absorption of 140 GHz frequencies, resistance of thermistor changes to a new value. This change in resistance of thermistor can be converted to a dc voltage change and amplified voltage change can be fed to computer through data acquisition card. Dialog based graphical user interface (GUI) has been developed in visual C++ language for average power measurement in dBm. WR6 standard rectangular waveguide is the input port for the sensor of power meter. Temperature compensation has been achieved. Moderate sensor return loss greater than 20 dB has been found over the frequency range 110 to 170 GHz. The response time of the power sensor is 10 second. Average power accuracy is better than ±0.25 dB within the power range from −10 to 10 dBm at 140 GHz frequency band.     

A telemetry-instrumentation system for monitoring multiplesubcutaneously implanted glucose sensors

An implantable potentiostat-radiotelemetry system for in vivo sensing of glucose is described. An enzyme electrode sensor measures the oxidation current of hydrogen peroxide formed by the stoichiometric conversion of glucose substrate and oxygen cofactor in an immobilized glucose oxidase layer. The sensor current is converted to a frequency and transmitted at programmable intervals (4, 32, 256 s) to a remote receiver. Low power CMOS circuitry is employed and device operation for up to 1.5 years is predicted using two series connected 250 mAh lithium cells. Crystal controlled RF frequencies uniquely identify each sensor allowing over 10 sensors within the same 10 m radius. A custom interface card allows a PC to program the receiver and handle the transmitted sensor data using software written in Microsoft C and QuickBasic. Software control allows on-the-fly sensor addition or subtraction to the sensor group being monitored. Over 10 sensors can be tracked long-term using the longest transmit interval, or four sensors can be tracked during short-term infusion studies when the transmit interval is reduced to 4 s. The design, construction, operation, and performance of the system hardware and software are described and evaluated     

基于共振光隧穿效应的加速度传感器

为了设计新型的加速度传感器，将共振光隧穿结构应用于传感元件，利用COMSOL软件对传感器的频率响应、灵敏度性能等关键要素进行了模拟仿真分析，搭建了实验平台，验证了共振光隧穿原理。结果表明，基于共振光隧穿效应结构的加速传感器在100Hz~3000Hz范围内、加速度为500m/s2的情况下，灵敏度可达到6.7dB/g。该传感器小巧轻便、结构简单，且具有较高的灵敏度，这为光学传感器的研究提供了新的方法和思路，具有广阔的应用前景。     

微型加速计全差分Σ-Δ接口IC

主要描述一种加速度感应系统全差分Σ-ΔCMOS接口IC。电容传感器接口由一个前端可配置开关电容(SC)电荷放大器和一个末端,一阶SCΣ-Δ调制器组成。本设计采用开关双采样技术(CDS)来消减低频噪声,能有效地隔离高性能Σ-Δ调制器和MEMS传感器。采用0.35μm CMOS技术,在3.3 V电源环境下能够理想工作。仿真结果显示该设计能达到0.55 V/g的精度。     

Technologies for highly miniaturized autonomous sensor networks

Recent results of the autonomous sensor research program HUMAN++ will be summarized in this paper. The research program aims to achieve highly miniaturized and (nearly) autonomous sensor systems that assist our health and comfort. Although the application examples are dedicated to human monitoring/assistance, the necessary technology development for this program is generic and can serve many wireless sensor applications. This multi-disciplinary program combines research on wireless ultra-low-power communications, research on 2D/3D integration and packaging platforms, energy scavenging techniques, as well as low-power and ultra-low-power sensor circuit design. An example sensor system is the wearable wireless EEG system.     

Design of Three-component Photoelastic Waveguide Accelerometer

In order to realize a high accuracy seismic exploration in the high electro-magnetic field and to improve oil producibility and recovery efficiency, a three-component photoelastic waveguide accelerometer is designed. Based on the photoelastic effect, the Mach-Zehnder integrated optical interferometer is designed to measure the three-orthogonal components of acceleration and the combined three-component simple harmonic vibrator is designed to reduce the cross-talk among the acceleration components. According to the variation of LiNbO3 waveguide phase under the action of the applied acceleration, the cross-axise sensitivity and transverse sensitivity ratio（TSR） were analysed. The results reveal that the accelerometer has wide band and good linearity. It can satisfy the sensor requirements of high accuracy seismic exploration. The main design parameters of the geophone system are： phase sensitivity： 1.86 × 10^-4 Rad ·m^-1 ·s^-2, natural frequency： 3 500 Hz, and the transverse sensitivity ratio： 0. 11%.     

三角剪切式微震监测压电加速度传感器设计

针对现有应用于矿井突水动力灾害防治微震监测传感器存在灵敏度低及频率范围窄的问题,该文提出了一种基于三角剪切式结构的微震监测压电加速度传感器。首先建立了压电加速度传感器的力学模型,对与固有频率和灵敏度有关的结构及材料参数进行了分析;然后设计了三角剪切型压电加速度传感器结构,探讨了压电陶瓷材料的选择,再利用ANSYS建立了压电加速度传感器有限元结构模型,分别对传感器进行模态分析、谐振响应分析与压电分析。仿真结果表明,设计的压电加速度传感器的工作频率和灵敏度满足微震监测要求。最后对设计的压电加速度传感器进行了标定和微震信号检测试验。结果表明,该传感器的谐振频率为6 300 Hz,工作频率为0.1~2 100 Hz,电荷灵敏度为34.626 pC/(m·s^-2)时,可完成对微震信号的检测,且具有宽频率范围和高灵敏度。     

基于ARM的智能三相电力监控仪表设计

介绍了一种电力监控系统智能三相电力监控仪表的设计方案,叙述了监控仪表的总体结构,给出了信号调理电路、开关量输入/输出电路和通信接口电路的设计方案,并说明了监控仪表的硬件配置图、监控界面和典型的应用电路。监控仪表以32位ARM处理器MB9BF218为控制核心,以ATT7022D为测量元件,实现了对电压、电流、频率、功率因数、有功功率、无功功率等三相电力参数的测量,具有RS485和以太网RJ45两种通信接口,可以方便地与其它设备一起构成电力监控系统。该监控仪表置具有功能完善、高性价比、高可靠性的特点,具有一定的应用价值。     

一种具有较大电容动态测量范围的接口电路

针对应用广泛的电容式传感器信号采集问题,提出了一种具有较大电容动态测量范围的高精度电容式传感器接口电路。该接口电路包括一个电容式有源电桥,以及用于将电容直接转换为频率的张弛振荡器,电路的频率输出用于确定微湿度传感器的响应特性。在基于薄膜的电容湿度传感器上进行了测试,实验结果表明,相比现有的类似电路设计,提出电路的结构更加简单且具有更大的电容测量范围和较高的精度,在1 p-600 p测量范围内的精度（误差百分比）<-2.14%,接口电路灵敏度为4.91 Hz/ppm,且输出频率与电容变化成线性关系。     

基于PC104与C8051F120的水下机器人环境监测系统设计

为了实现对水下机器人周围环境的监测,提出了一种基于PC104与C8051F120的水下机器人环境监测系统设计方案,并完成系统的软硬件设计.该系统的硬件部分主要是采集下潜深度传感器、姿态传感器、温湿度传感器的数据,软件部分采用用Visual C＋＋ 6.0设计了监控界面.该系统能够实时显示视频和各传感器数据.实际测试表明,该系统具有稳定性高、准确性高的特点,达到了设计要求.     

基于光纤压力传感器的管道监控系统研究

针对运输管道埋设于土壤中面临的泄漏或堵塞点难发现、难定位的问题,结合光纤压力传感器高灵敏度、高抗干扰的特性,设计了一种基于光纤压力传感器的管道监控系统。系统采用包覆有合适热膨胀系数材料的单模光纤组成的偏振型压力传感器,能很好地克服外界环境温度扰动;采用模块化设计的压力敏感探头以20 m间距均布于管线上,形成信号点阵列源;结合点阵列数据重构与插值定位算法确定故障点的位置。结果表明:该系统的光纤压力传感器可有效克服温度变化对传感测量的不良影响,5.5 km范围内对故障点的定位精度在1 m内。