数字化折页机控制系统开发

针对当前我国折页机数字化程度低的问题,对数字化折页机的控制系统进行了研究,开发了折页机硬件控制系统和上位机控制系统,实现了折页机的数字化控制.上位机系统的开发,简化了折页机操作方式.折页模式的自动预置大大降低了系统的工作准备时间,减少了因系统预置造成的浪费,提高了工作效率.JDF网络接口可视系统与印刷流程控制系统通讯,有利于实现折页机的远程监控.     

采用容栅技术的液位检测系统设计

采用容栅技术的液位检测系统是指在磁翻柱液位计的基础上采用了容栅传感器．通过液位的变化使得容栅传感器的电容发生改变,进行测量的一种检测系统。它既具有磁翻柱液位计的高密封、防泄漏、可靠性好等优点。又能满足在高温环境下实现电信号的远传。     

容栅式大位移测量系统的应用技术

容栅式大位移测量系统利用单片机对传感器传输的位移信号完成采集，转换输出，并具有预置，清零功能。在此基础上对系统的抗干扰性能及有关措施进行分析和设计。     

容栅传感器若干误差的实测与分析

容栅传感器若干误差的实测与分析安徽大学电子工业学院王家福，马修水，史福元，杨明建一、引言八十年代中期，安量、上量等量具厂引进了国际上领先的容栅传感器技术，并在量具上应用，通过近十年的攻关，基本实现了数显卡尺类系列产品国产化。但是，产品水平、产品质量与...     

容栅传感器位移测量系统研究

本文介绍了容栅位移传感器的结构和工作原理,并在传统容栅传感器基本原理研究基础上,深入研究了鉴幅式容栅系统和鉴相式容栅系统信号激励方式和信号输出规律,分析开发出单片机和数字鉴相器为核心的鉴相式容栅高度测量仪。     

容栅电子长度测量系统

一、概述线纹电子长度测量系统中通常包括光栅,同步感应器,磁栅和容栅四种测量系统。容栅电子长度测量系统是七十年代末,八十年代初国际上开始发展起来的一种新颖位移传感器,国内在八十年代陆续引进了容栅器件进行组装。容栅测量系统有几种不同的类型,但其基本原理都应用了电容差动感应的原理。本文介绍的是一种高分辨率的容栅电子长度测量系统。二、工作原理图1　　容栅电子长度测量系统的基本原理如图1所示,它包括一个差动电容传感器,在电容传感器的一边至少有一块接收极板,在电容传感器的另一边至少有两块发射极板。电容传感器两边能作相…     

容栅传感器的误差平均效应

介绍了容栅传感器的工作原理，进行了容栅传感器的精度分析，提出了一种容栅传感器刻线误差的新而具体的计算方法，按该方法计算出的结果与实测得到的结果极为吻合。据此，对容栅传感器的主要元件（动、定栅板）的制造精度要求不必过高。因而，这个计算方法具有重要的实用价值。     

容栅传感器的误差平均效应

介绍了容栅传感器的工作原理，进行了容栅传感器的精度分析，提出了一种容栅传感器刻线误差的新而具体的计算方法，按该方法计算出的结果与实测得到的结果极为吻合，据此，对容栅传感器的主要元件（动，定栅板）的制造精度要求不必过高。因而，这个计算方法具有重要的实用价值。     

一种绝对式容栅测量新技术

在综合分析、比较现有容栅测量技术的基础上,介绍了一种绝对式容栅测量技术.这种技术克服了传统相对式容栅测量系统中存在的缺陷,利用两级耦合多精度合成实现测量位置的绝对编码,实现了高精度、大量程测量.首先介绍了用于高精度测量的容栅测量系统构成,讨论了绝对式测量的工作原理.给出的系统检测电路解决了传统鉴相型检测电路中滤波效应导致信号精确性受到损坏以及需要较长稳定时间的问题.     

容栅传感器静,动态联合数学模型

通过对容栅传感器的定性分析和定量计算，建立了它的静、动态联合数学模型，全面，准确地揭示了传感器的工作原理。     

电容式密度传感器低密度液氢校准实验研究

设计、搭建了一套可调节密度式多点电容式密度传感器校准装置,并进行了电容式密度传感器低密度液氢的校准试验。实现了对液氢在一定低密度范围内(50—70kg/m3)的调节,突破了传统的常压单一密度点校准技术,实现了液氢多密度点的校准,提高了校准结果的可靠性。对电容式密度传感器校准装置各因素引入的不确定度分量进行了评定,分析得到了该装置的不确定度,试验结果表明采用给液氢增压的方式可以对液氢低密度进行准确控制,该调节装置的不确定度满足电容式密度传感器校准设计要求,并且能够对电容式密度传感器在多种低温流体介质中进行较宽密度范围校准。     

柔性极板电容式液位传感器的研究和应用

目的 为了解决传统硬质极板电容式液位传感器在曲面容器上性能不佳的问题.方法 从寄生电容的基本原理出发,研发一种可以包覆于圆柱面容器的柔性极板电容式液位传感器,建立液位与电容量间的数学关系,完成相应的软、硬件设计,通过STM32与柔性极板电容式液位传感器之间的I2C通信,实现液位传感器的在线水位检测,完成传感器性能测试实验,包括线性度、重复性、迟滞特性,并提出一种基于该传感器的流量测量方法.结果 该传感器工作稳定,具有良好线性度,重复性误差为2.70％,在有效测量范围的迟滞特性参数都小于1.69％.结论 该柔性极板电容式液位传感器安装使用便捷、与容器外壁贴合度较好,且测量结果不受容器水平横截面积、待测液体成分的限制,可以实时监测连续液位的变化.制作的传感器可以用在直径20 mm和更小的待测容器上,也可用作微小流量测量.     

The influence of electric-field bending on the nonlinearity ofcapacitive sensors

Three-layered electrode structures are often employed in multiple-electrode capacitive position sensors. Even when advanced algorithms and well-designed guarding electrodes are used, the electric-field-bending effect is still one of the major contributors to the nonlinearity of capacitive position sensors. In this paper, the effects of electric-field bending on linearities of five capacitive linear-position sensors have been studied based on a physical model of the capacitive sensor. It is shown that the effect of electric-field bending on linearities strongly depends on the sensor structures, and that it is significantly reduced when advanced sensor structures and algorithms are used. The results are very useful for optimizing the sensor structure according to its application     

Humidity sensor structures with thin film porous alumina for on-chip integration

Our aim was to produce a cheap, reliable, low-power and CMOS-MEMS process compatible relative humidity (RH) capacitive sensor that can be incorporated into a state-of-the art wireless sensor network. Porous alumina, produced by electrochemical oxidation of aluminum thin film under anodic bias (AAO, Anodic Aluminum Oxide) was used for the purpose of the sensing layer. We prepared two different capacitive sensor structures on silicon substrate using semiconductor processing steps and anodic oxidation in addition. The first sensor has an ultra-thin, vapor-permeable palladium upper electrode, while in the second case, an electroplated gold-grid is used for the same purpose. The highest achieved average sensitivity is approx. 15 pF/RH%, which is much higher than the values found in product catalogues of discrete, off-the-shelf capacitive humidity sensors (0.2-0.5 pF/RH%).     

线面式电容传感器结构设计与传感特性研究

提出了一种基于自阻尼垂向测量参考的线面式电容传感器,对垂向运动中的残留水平位移进行精确测量。线面式电容传感器利用细丝电极作为直接垂向测量参考,消除了间接参考在其转换过程包含的系统误差;同时采用细丝末端的液体阻尼器保证细丝电极的稳定性。实验表明:在0.38~0.4pF范围内,线面式电容传感器的分辨力优于0.05μm,短期稳定性约为0.1μm。     

Nanostructured Metal Oxide Thin Films for Humidity Sensors

Capacitive humidity sensors were fabricated using countersunk interdigitated electrodes coated with amorphous nanostructured TiO₂, SiO₂, and Al₂O₃ thin films grown by glancing angle deposition. The capacitive response and response times for each sensor were measured. The sensor utilizing TiO₂ exhibited the largest change in capacitance, increasing exponentially from ~ 1 nF to ~ 1muF for an increase in relative humidity from 2% to 92%. Adsorption and desorption response times were measured using flow rates of 2.5 l/min and were between 90 ms and 300 ms for the sensors studied here. A simple model of the capacitive response of the devices has been developed and used to calculate the dielectric constant of the combined system of our films and adsorbed water. The obtained dielectric constants are found to be much higher than bulk or literature values for similar systems.     

Tracking Control of a Nanopositioner Using Complementary Sensors

Piezoelectric tube actuators are widely used in atomic force and scanning tunneling microscopy (STM) for nanoscale positioning. There has been a consistent effort to increase the scan speed of these actuators using feedback control techniques. A feedback controller requires a measurement of the scanner's deflection, which is often provided by a capacitive sensor. Such measurements are corrupted by sensor noise, typically in the order of 20 pm/ radicHz rms. Over a bandwidth of 10 kHz, this translates into an rms noise of 2 nm, clearly inadequate for applications that require subnanometer positioning accuracy, e.g., STM. In this paper, we illustrate how the strain voltage induced in a free electrode of the scanner can be used as an additional displacement signal. The noise level corresponding to the strain signal is about three orders of magnitude less than that of a capacitive sensor, making it an ideal choice for nanopositioning applications. However, it cannot be used for dc and low-frequency measurements. A two-sensor-based controller is designed to use the capacitive sensor signal at low frequencies, and the strain displacement signal at high frequencies. By limiting the capacitive sensor feedback loop bandwidth to less than 100 Hz, the rms value of the noise is reduced to well below 1 nm. For almost the same noise level, the two-sensor-based control structure achieves a closed-loop bandwidth of more than three times that of the single-sensor-based controller.     

Capacitive Transduction for Liquid Crystal Based Sensors, Part II: Partially Disordered System

This paper presents the capacitive transduction technique involved with liquid crystal (LC) based sensors in partially disordered systems. These sensors have the potential applications in chemical and biological systems. The theory for tracking the average molecular deformation (state of alignment) and degree of ordering of anisotropic and partially disordered LC film via capacitive sensing is investigated. This system is modeled using the Q-tensor approach in modeling uniaxial LC material. The proposed sensor design is an interdigitated electrodes structure. Transverse and fringing capacitances as function of the molecular deformation are calculated. It is verified that three capacitance measurements are required to track the average molecular orientation and the degree of disorder in the LC film. The sensitivity for the sensor at different alignments and ordering degree is also studied. Toward practical sensor, neuro-fuzzy system is modeled to simulate the capacitive transduction and to monitor the LC profile. Sensors are fabricated and tested. Both the experimental and calculated capacitances are presented and compared.      

气象用湿敏电容传感器的稳定性测试与分析

为研究湿敏电容传感器的稳定性特征,利用14支湿敏电容传感器静态测试数据,用误差年漂移量定量表征湿敏电容传感器的稳定性,并对误差年漂移量的变化规律及影响因素进行分析。结果表明,湿敏电容传感器的稳定性受温度、温度和湿度的交互作用以及厂家制造水平的影响,低温时稳定性较差;室温时稳定性随湿度升高而降低。经过一年的使用,78.6%的湿敏电容传感器无法满足技术指标要求。