高压压差传感器的研究

本文介绍了我们研制的一种新型压差传感器,该传感器可用于高基础压力下压力差的测量。本文首先叙述了压差传感器的基本原理和计算方法,然后给出了对该压差传感器在0～51MPa压力范围内进行标定的结果。实验表明,该压差传感器具有较高精度,可以满足实际测量要求。     

高可靠性压差传感器的设计与测试

压差传感器用于伺服系统作动器两腔压力差的测量,文中针对高可靠性、高精度、耐高温、小型化压差传感器的应用需求,提出了高可靠性压差传感器的设计方案并进行测试,主要包括芯体设计、结构设计和电路设计。该产品采用SOI硅晶圆材料制作压力敏感芯片,可在150℃下正常工作。传感器通过性能测试以及环境试验,试验结果表明该传感器能够满足实际使用要求,在150℃下温度漂移和灵敏度漂移均小于±0.1%FS/℃。     

基于FPGA的大气数据采集系统的设计

大气数据的采集是影响无人机飞行控制的主要因素,为了实现对该信号源的采样,根据大气数据的高度和空速的测量原理,选用简易小型空速管作为采样通路,采用芯片级动压和静压传感器作为信号源,设计了基于FPGA的大气数据采集系统,并且在DSP处理器上实现对数据的算法处理。最后通过在某小型无人机上的飞行试验结果表明,该大气数据采集系统能够实现对空速和气压高度的获取。     

基于LabVIEW的滤清器在线干式检漏系统设计

针对柴油滤清器湿式检漏效率低、成本高等问题,研究了基于LabVIEW的滤清器在线干式检漏系统。该系统利用高精度微压差传感器和稳定气压回路测量滤清器进、出口压力变化,借助NI公司的高性能数据采集卡和其强大的软件平台实现对传感器数据的采集、处理及结果输出。试验结果表明该系统能快速、简单、准确地检测出滤清器的泄漏速率,验证了系统的可行性。     

压差传感器信号测量异常问题分析及改进

柴油机后处理为了实现DPF的再生循环使用,在DPF上装有压差传感器。作为监控DPF状态的传感器,压差传感器信号测量的准确性直接影响到DPF的功能。本文通过对DPF压差传感器信号测量异常导致的发动机亮故障灯问题进行分析探讨,通过试验验证,明确地指出了信号测量异常的故障原因及解决措施。     

新型磁性液体微压差传感器的设计及耐压分析

传感器是磁性液体的重要应用领域之一。为弥补现有磁性液体微压差传感器的不足,设计了一种新型的磁性液体微压差传感器,该传感器的复合磁芯由磁导率高的1Cr13和永久磁铁构成,磁性液体被吸附在永久磁铁的端部形成环状起到润滑和密封的作用,敏感元件采用1Cr13,转换元件采用对称线圈。当磁芯进入线圈后,使得线圈电感发生变化,电桥电路输出明显的电压信号。在此基础上,提出了回复力的线性程度和磁性液体环的耐压能力决定了磁性液体微压差传感器的量程范围,并通过理论推导、仿真分析和实验研究的手段证明了磁性液体环的密封耐压能力能够满足磁性液体微压差传感器的测量要求。该传感器体积小、成本低、便于安装,具有很强的实用价值。     

探空温湿压系统研制

介绍了用于测量大气湿度、温度和气压探空集成传感器系统.利用集成温湿压传感器采集信号,测量采用24位AD精度MCU,借助CC1000将信号调制,MAX2235将信号功率放大无线发送.给出了集成温湿压传感器结构、测量系统的原理、测量系统的硬件框图及关键软件的设计流程.实验结果证明该系统在满足测量精度的条件下,降低了系统的体积和成本.     

高速光电式转矩传感器的测量原理与动态特性分析

基于现有的磁电式、光电式转矩转速传感器的测量原理,提出了一种高速光电反射式转矩传感器,介绍了传感器的基本结构和测量原理,分析了传感器的扭振动态特性.该传感器以激光头和反光条纹为发讯器,结构简单、性能稳定.与现有的转矩传感器相比,该系统可用于速度在105 r/min以上的超高速回转机械(如航天叶轮泵、高速轴承等)转矩的测量.     

基于应变式传感器的料位测控系统

针对水泥等行业中对料位进行实时测量的需求,开发出一种新型的料位测控系统.系统的传感器采用应变式传感器,传感器的核心部分是应变片,通过应变片感测物料的侧压力并获得料位信息.传感器是该系统的关键部分,通过传感器的优化设计可以很好地实现在恶劣环境下的测量工作,很好地解决了在恶劣环境下高粉尘、干扰大等普通测量方法无法解决的问题.采用以MSP430为核心的控制电路,使该系统具有了高速、稳定及实时测量的优点.     

空间机械臂模块化关节传感系统设计

设计了空间机械臂模块化关节的传感系统,该系统包括力矩传感器、位置传感器、温度传感器和限位传感器等多种传感器.该系统为空间机械臂提供了丰富的感知能力,可实现位置控制、力控制及主动柔顺控制等多种控制策略.为了实现对关节位置的高精度测量,采用传感器信息融合的方法,并建了关节位置精度测量实验台.实验结果表明,关节位置精度可达0.03°,满足技术指标要求.     

Evaluation of a prototype thermal anemometer for use in low airspeed drying measure calculations

An indicator of the drying rate of an airflow is the product of airspeed and humidity ratio (or vapour pressure) deficit. Significant sensor errors are present in both the high relative humidity and low airspeed ranges. Also, the margin for error is small relative to the desired drying measure for mushroom growth. The objective of this study was to evaluate the suitability of a low-cost prototype anemometer for use in a mushroom growth environment. A calibrated thermal anemometer was used as a performance reference for the prototype airspeed sensor. Case studies were carried out on two prototype airspeed sensors to determine suitability for use in this drying measure application. The study required the construction of a custom wind tunnel to produce a unidirectional airflow. The sensors (housed in the wind tunnel) were evaluated in an environmental chamber over the range of relevant temperatures. Results show promise for the future application of the prototype sensors subject to the sensors being thermally compensated. Reduction in the cost of a low velocity anemometer by an order of magnitude, would facilitate their purchase and subsequent use for airspeed control by the grower, thus broadening the range of control variables available to the grower.     

基于 C 4 D 技术的非满管液体流速测量方法研究

为满足目前小型化设备中液体流速测量的需求,通过将空间滤波测速与电容耦合非接触电导测量(C~4D)技术相结合,提出了一种适用于非满管液体流速测量的新方法。设计了一种轴向两电极结构的C~4D传感器,采用COMSOL仿真软件建立了传感器的三维仿真模型,并对其空间灵敏度分布特性进行了分析,然后基于该传感器的空间滤波效应对液体流速测量原理进行了理论推导,并采用等效峰值频率的方法得到了速度测量的数学表达式;在此基础上,设计了一套可适用于空间滤波的C~4D液体流速测量系统,并通过该测量系统验证了C~4D传感器具有良好的空间滤波效应,且实验结果表明,该测量方法具有良好的可行性,在1.39～2.35 m/s的速度范围内,测量速度的绝对误差均在5%以内。     

磁致伸缩压力传感器设计及其输出特性

研究了铁镓合金(Galfenol)的磁致伸缩特性,提出一种基于Galfenol的新型磁致伸缩压力传感器,以实现机器人的触觉力精确感知。该传感器利用磁致伸缩逆效应将压力转换为电压信号,从而完成对压力的精确测量。设计、制作了磁致伸缩压力传感器,采用双永磁体回形磁路优化了压力传感器的磁场。对传感器进行了理论分析与实验研究,讨论了偏置条件、外压力等因素对输出电压峰值的影响。实验结果表明,在偏置磁场为4.8kA/m、施加的压力为2.5Hz、6N时,传感器的输出电压峰值达16mV,且输出电压峰值与压力呈较好的线性关系。研制的传感器具有结构简单、线性度好、反应速度快等特点,可以满足机器人触觉感知的需求,也可应用于其他领域的压力测量。     

An instrumentation system for multi-parameter measurements of gas-solid two-phase flow based on Capacitance-Electrostatic sensor

In this paper, an instrumentation system for the measurements of local solid volumetric concentration, local solid velocity, local solid mass flowrate and solid mass flowrate in gas-solid two-phase flow system is developed. It is based on a new type of a Capacitance-Electrostatic sensor (CES). The CES sensor is mainly composed of a capacitance electrode array and two electrostatic electrode arrays. The optimum design of the sensor is achieved by finite element method. The capacitance electrode array is employed to detect the solid distribution over the cross-section of the pipe, and the local solid volumetric concentration measurement is further derived. The electrostatic electrode arrays are used to measure the local solid velocities in conjunction with cross-correlation method. From the local solid velocity and local volumetric concentration, the solid mass flowrate and the local solid mass flowrate can be achieved. The developed system for the local solid volumetric concentration measurement is verified through analogue simulation experiments and static experiments. Finally, the system is employed to measure the local solid volumetric concentration, local solid velocity, local solid mass flowrate and solid mass flowrate on a belt conveyor. The experimental results show that the measurement error of the local solid volumetric concentration measurement results are less than 10.43% for solid local volumetric concentration ranging from 0.02 to 0.56, the standard deviations of the local solid velocity measurement results are less than 0.42 for solid velocity ranging from 3.5 m/s to 15.0 m/s, and the relative error of the solid mass flowrate is within −19.6% to +14.9% for solid mass flowrate ranging from 0.006 kg/s to 0.103 kg/s, indicating that the system is capable of achieving multi-parameters measurement in gas-solid two-phase flow system.     

Impacts of inflow conditions on the measurement stability of a turbulence-mitigation based liquid concentration detection system

Liquid concentration plays an important role in many industrial processes. We designed a concentration detection system based on the principle of differential pressure, and introduced a turbulence elimination structure (TES) to improve the internal flow field. In order to explore the influence mechanism of the internal flow field on the detection, two models were used for numerical simulation under different working conditions. The results show that TES can effectively restrain the velocity fluctuation and turbulence intensity change of the flow field in the observation trough, thus forming a good measurement environment. The experimental results show that the measurement signal of the model with TES is more stable, and a stable detection area is formed between sensor 1 and sensor 3, which can be used for efficient detection of the sensor system. For the model with TES, the optimal speed range of 0.3–0.8 m/s was determined through experiments.     

A wind tunnel for anemometer calibration in the range of 0.2-1.25 m/s

In order to calibrate different types of anemometers in a low-speed range (0.2-1.25 m/s) using pressure measurements, a wind tunnel has been built and characterized. The wind tunnel has a low-speed section and a high-speed section. The wind tunnel calibration has been performed by means of comparison of airspeed at the test cross section (low-speed) and at the reference cross section (high-speed). Measurements have been taken with a calibrated hot-wire anemometer and static and total probes respectively. A linear fitting is used to relate reference and test airspeed. A model based on mass conservation law has been developed. Calculations have been made with and without introducing the effect of the speed profile. Uncertainties of the experimental calibration are presented.     

差动结构的平面二维时栅位移传感器

为了解决采用两套高精度一维传感、装置测量二维位移时存在的测量系统复杂、检测同步性难保证和解耦运算复杂等问题，提出了一种基于差动结构的二维感应信号直接解耦方法，用于研究一种平面线圈型二维时栅位移传感器。立足于传统电磁式时栅技术，构建了二维位移直接解耦测量模型，并设计了传感器的基本结构。利用ANSYS Maxwell 建立了传感器三维结构模型并进行了电磁仿真，并对仿真结果进行误差分析和溯源。基于此研制了传感器样机并进行了实验。实验结果表明：样机在79.2 mm×79.2 mm测量范围内，X方向误差为91 μm，Y方向误差为74 μm，可实现二维位移同步检测和直接解耦测量，且测量系统结构简单、体积小，对研究更高性能的二维时栅具有重要参考价值。     

面向固-液两相软性磨粒流嵌入式实时测控系统

针对固-液两相软性磨粒流精密抛光方法中流道微小,无法采用常规直接信号传感器的问题,提出了一种基于二次信号-加速度振动信号的软性磨粒流监测方法。通过小波包分析提取了振动信号的特征。结合基于有限状态机理论与基于嵌入式实时操作系统的并发多任务的程序设计方法,采用面向对象技术开发了一种测控软件框架。采用Linux和DSP／BIOSRTOS实施了双操作系统信号处理技术,开发实现了一个面向软性磨粒流的,具有通用多通道高速数据采集功能的智能化嵌入式实时测控平台。研究结果表明,该系统具有易扩展与易交互的优点。     

Study of Geophysical Parameters by Well Information-Measuring Systems on Regenerative Sources

The information-measuring system is intended to continuously determine a set of geophysical parameters of worked-out areas of running oil reservoirs under pressures of up to 100 mPa. The system consists of ground and well telemeter units, and an acoustic waveguide based on a well scratcher wire is used as a communication link between them. Due to the permanent connection of the housing of the well instrument and scratcher wire and the use of a power supply unit based on a current generator in the form of a spinner rotameter with rotor and stator windings, the well instrument is self-contained and can operate in hostile environments with pressure differences of up to 20 mPa. The measurement ranges are as follows: for the flow velocity sensor, the range is 0.001–0.1 m/s with a 0.5% error; for the pressure gage, it is 0–90 mPa with a 0.1% error; for the temperature sensor, the range is 0–125°C with a 0.1% error; and for the humidity sensor, it is within a humidity range of 50.1–99.9% with a 0.1% error. These systems are multichannel due to the self-synchronization method of the recovered signals of the sensors in the ground part with a 0.1% total reception/transmission error determined by the analog-to-digital conversion.     

汽车罐车耐压试验计算机测控系统的研发

针对汽车罐车耐压试验数据测量不精确、操作繁琐等问题,对汽车罐车耐压试验的系统架构、技术参数和试验控制等方面进行了研究,探索了一种由计算机控制电磁阀、传感器和试压泵来实现试验自动控制的方法,提出了基于单片机技术、传感器技术和测控技术的汽车罐车耐压试验计算机测控系统。通过对整个试验系统的分析,建立了试验管路、微机测控系统和计算机管理系统之间的关系,并对试验管路的设计、微机测控系统电路的设计、试验数据的处理和试验自动控制的方法进行了分析研究。研究结果表明:该测控系统能够高效地完成试验进程,提高试验数据的精度,生成试验报告,并且减轻试验操作人员的工作强度。