基于电容式传感测头的电容检测系统的设计

针对纳米尺寸测量领域的不同测量要求,尝试开发一种基于电容传感器的微触觉测头及其电容检测系统。阐述了测头的结构原理和电容传感器的工作原理,研制了基于电容传感器的微触觉测头。测头的测量原理表明:微小电容检测电路是整个电容检测系统的关键部分。该微小电容检测电路选用电容/数字转换器(CDC)AD7747芯片,分别编写了单片机与该芯片的I2C通信程序和单片机与上位机间的串行通信程序,实现了微小电容的采集和处理,简单进行了电容式传感测头的轴向性能的测试实验。实验表明:电容式微触觉测头的分辨率为0.02μm,重复性较好,证实了此电容式微触觉测头的可行性。     

电容式扭矩传感器的微小电容检测系统设计

针对电容式传感器输出微小电容信号检测难的情况,结合圆容栅扭矩传感器微小电容检测电路中遇到的问题,说明了圆容栅扭矩传感器的基本工作原理,设计了利用LC共振检测微小电容变化的系统.利用LC振荡电路在共振频率附近急剧变化180°的特性,当C的值发生变化时,相位对应的角度会发生比较大的变化,将电容变化转变为对相位差的检测.并在...     

不同检测电容结构对MEMS电容传感器性能的影响分析

改进传感器检测电容几何结构能有效改善传感器的性能。本文对梳齿电极结构、栅形电极结构及梳栅电极结构检测电容的性能特点进行分析比较,重点分析了振子质量、空气阻尼、系统阻尼系数比以及灵敏度等特性,得出在相同的外轮廓尺寸、支撑梁、振子厚度以及振子到衬底的距离的条件下,栅形结构传感器的振子质量最大,空气阻尼最小,适合制作高分辨率的传感器;在大气下,梳齿结构灵敏度增加的同时空气阻尼力也会增加,且振子质量较小,适合制作高灵敏度,低分辨率传感器结构;梳栅结构的特点居于两者之间,适合制作需要兼顾分辨率和灵敏度的传感器。通过实例计算,证明了该结果。     

基于MEMS传感器的飞行姿态指示系统

采用MEMS传感器设计了一种飞行姿态指示系统.给出了系统的原理及整体框架,重点阐述了系统的硬件电路和软件的设计.系统以32位处理器STM32F103C作为控制核心,采用MEMS加速度计和磁传感器测量各轴向的重力加速度分量和地磁强度,进而确定飞行姿态.与传统姿态指示系统相比较,该系统体积小、功耗低.试验表明该系统具有较高的可靠性,适合无人机等体积小、机动性低的飞行器.     

基于MEMS传感器的脊柱形态检测系统设计

鉴于传统的脊柱检测普遍具有放射性,设计出基于MEMS传感器的无放射性脊柱形态检测系统。检测系统使用MEMS姿态传感器测量被测人背部脊柱姿态角度,由微处理器STM32进行数据读取、分析、处理后,在显示模块上显示检测结果,并将检测结果发送到上位机。检测系统可以分析被测人脊柱的Cobb角和轴向躯干旋转角度ATR,判断被测人脊柱是否畸形。     

圆柱面径向微小尺寸测量用特殊平行板电容传感器讨论

用平行板电容传感器测量微小尺寸可获得高精度，好的动态特性和易于实现信号转换及后续控制与处理，但用普通平行板电容传感器一为测量圆顼径向微小尺寸则受到精度，量程范围及诸多因素的限制。     

基于图像处理的产品表面缺陷检测系统研究

随着嵌入式技术的发展,基于图像处理的产品表面缺陷检测技术的优势越来越突出,其技术主要包括产品表面图像的采集、匹配和识别。本系统采用单精度浮点运算的STM32F405作为核心处理器,CMOS彩色数字摄像芯片OV7610作为图像采集传感器,并在VC++环境下使用面向对象的方法设计控制程序,主要用于产品表面图像的采集与处理。实验结果表明,该系统工作稳定,实时性和可控性达到设计要求。     

电容式传感器微电容检测电路的研究

基于MEMS技术研制的微电容传感器,其有效电容的实际变化量仅为飞法级。实验表明,二元调宽式信号拾取专用集成电路BH5001为检测微电容变化量建立了一个高信噪比的平台,结合优良的巴特沃斯低通滤波器和高品质的差动放大器,即可完成微电容的检测。     

用电容传感器测量 微小振幅时的间距补偿

用电容传感器测量振动体振幅,其灵敏度随设定的间距值变化,影响精度.作者以电路技术简捷地克服了这一不足,很有参考价值,今节载,以飨同行.本文系林明邦教授征得笔者同意后,请孔合平翻译,经审核,推荐给本刊.为节约篇幅,编辑部作了部分改编.     

一种小型固定翼无人机姿态测量系统的设计

针对小型固定翼无人机设计中对姿态测量系统小型化、低成本的需要,设计了以STM32F405为处理核心的低成本的姿态测量系统。系统采用MARG传感器方案,利用优化的梯度递减算法对采集的数据进行处理,将处理结果通过改进的互补滤波算法完成数据的融合,最终完成飞行姿态参数的解算。实验验证表明,所设计的系统具有实时性、低功耗、低成本、小型化等特点,能较好地完成无人机的姿态角数据的测量,具有较强实用性。     

电容式MEMS加速度传感器在气囊系统中的应用

安全气囊系统作为汽车被动安全的核心组成,有着极为重要的作用.为了提高其性能,设计了一种基于MEMS的外围加速度传感器的系统.该系统通过微机械结构检测汽车碰撞时的加速度,再通过一体式的专有集成电路对信号进行处理,然后将数据经总线传送到安全气囊控制器进行逻辑运算.通过实际碰撞测试,证明该设计系统能增强碰撞识别度和提早点火时间,极大地提高了安全气囊系统的性能.     

A novel high sensitive MEMS intraocular capacitive pressure sensor

This paper presents a novel high sensitive MEMS capacitive pressure sensor that can be used as a part of LC tank implant circuit for biomedical applications. The pressure sensor has been designed to measure pressures in the range of 0–60 mmHg that is in the range of intraocular pressure sensors. Intraocular pressure sensors are important in detection and treatment of an incurable disease called glaucoma. In this paper two methods are presented to improve the sensitivity of the capacitive pressure sensor. First low stress doped polysilicon material is used as a biocompatible material instead of p++silicon in previous work (Gu in Microfabrication of an intraocular pressure sensor, M.Sc Thesis, Michigan State University, Department of Electrical and Computer Engineering, 2005) and then some slots are added to the poly Si diaphragm. The novelty of this research relies on adding some slots on the sensor diaphragm to reduce the effect of residual stress and stiffness of diaphragm. The slotted diaphragm makes capacitive pressure sensor more sensitive that is more suitable for measuring intraocular pressure. The results yield a sensor sensitivity of 1.811 × 10^?5 for p++silicon clamped, 2.464 × 10^?5 1/Pa for polysilicon clamped and 1.13 × 10^?4 1/Pa for polysilicon slotted diaphragm. It can be seen that the sensitivity of the sensor with slotted poly Si diaphragm increased 6.2 times compared with previous work (clamped p++silicon diaphragm).     

A high-performance MEMS capacitive strain sensing system

This paper describes the design of a functional strain sensing module with large dynamic range (80 dB), DC to 10 kHz response, high resolution, and mini size for industrial applications, such as the rolling-element bearings research. The design of the MEMS capacitive strain sensor employs mechanical amplifications of package design and buckle beams as well as the linear differential comb capacitor. The sensor is interfaced with a low noise charge amplifier, mixer, and filter circuits to provide an analog output that demonstrated a resolution of 0.09 microstrains with a maximum range of ±1000 microstrains. The sensor and the electronic circuits, including a temperature sensor, can be integrated on a chip, and packaged as a small functional unit. Additional electronics were integrated with the interface circuit on the chip that provide A/D conversion, radio frequency power supply, and digital signal telemetry to a near-by control unit. Preliminary test results are compared with the design simulation.     

A dual-axis MEMS capacitive inertial sensor with high-density proof mass

This paper reports a novel dual-axis microelectromechanical systems (MEMS) capacitive inertial sensor that utilizes multi-layered electroplated gold. All the MEMS structures are made by gold electroplating that is used as a post complementary metal-oxide semiconductor (CMOS) process. Due to the high density of gold, the Brownian noise on the proof mass becomes lower than those made of other materials such as silicon in the same size. The single gold proof mass works as a dual-axis sensing electrode by utilizing both out-of-plane (Z axis) and in-plane (X axis) motions; the proof mass has been designed to be 660 μm × 660 μm in area with the thickness of 12 μm, and the actual Brownian noise in the proof mass has been measured to be 1.2 \({\upmu}{\text{G/}}\sqrt {\text{Hz}}\) (in Z axis) and 0.29 \({\upmu}{\text{G/}}\sqrt {\text{Hz}}\) (in X axis) at room temperature, where 1 G = 9.8 m/s². The miniaturized dual-axis MEMS accelerometer can be implemented in integrated CMOS-MEMS accelerometers to detect a broad range of acceleration with sub-1G resolution on a single sensor chip.     

A high sensitive MEMS capacitive fingerprint sensor using slotted membrane

In this paper a novel single-chip microelectromechanical systems (MEMS) capacitive fingerprint sensor with slotted membrane is developed to improve the sensitivity. The capacitive sensor consists of a thin, flexible membrane and a rigid back plate with air gap. In this study with making slots in upper electrode to decrease the mechanical stiffness of the membrane, using proportional T-shaped protrusion on diaphragm in order to concentrate the force from finger ridges, making holes in lower electrode to reduce the air damping and using low stress material for diaphragm, we have been succeeded to design a novel MEMS fingerprint sensor with high sensitivity compared with the previous works (Sato et al., IEEE Trans Electron Devices 52:1026–1032, 2005; Damghanian and Majlis, 2008 IEEE International Conference on Semiconductor Electronics (ICSE 2008), pp 634–638 2008). The behaviors of the fingerprint sensor with clamped and slotted membranes are analyzed using the finite element method (FEM). The results yield a sensitivity of 1.44 fF/Mpa for the clamped and 3.22 fF/Mpa for the slotted fingerprint sensor with a 50 × 50 μm² diaphragm. The sensitivity of the slotted structure is increased 2.236 times.     

电容式MEMS超声传感器设计与分析

目前电容式MEMS超声传感器（CMUS）多为收发一体结构,但二种工作模式对传感器结构要求存在很大差异,设计时为了兼顾收发性能往往不能使传感器性能达到最优;此外,传统的电容式MEMS超声传感器还存在寄生电容大的缺点。针对以上问题,基于收发分离的思想,设计了一种专用作超声接收的MEMS电容式传感器,结构上采用上下电极引线互错,单元间电极联线交错的方式来减小寄生电容。通过理论分析和ANSYS仿真得到所设计传感器的最佳工作电压为586V,灵敏度为174.2fF/Pa,满足现有超声接收传感器的应用要求。     

MEMS热电堆传感器的红外探测系统

为了实现远距离红外目标的运动和静止状态的识别,设计了基于热电堆红外传感器的红外探测系统,系统包括梯析(GRIN)透镜、微系统(MEMS)热电堆传感器、信号调理电路、数据采集电路和识别算法.探测结果表明:在相同光路系统的情况下,探测系统实现了比热释电系统更远的探测距离,实现了动态目标和静态目标的识别,并基于探测目标温度、辐射面积的区别,实现了人、车辆和其他红外目标的分类识别,可为红外目标的探测识别提供一种新的解决方案.     

CMOS integrated elliptic diaphragm capacitive pressure sensor in SiGe MEMS

A novel CMOS integrated Micro-Electro-Mechanical capacitive pressure sensor in SiGe MEMS (Silicon Germanium Micro-Electro-Mechanical System) process is designed and analyzed. Excellent mechanical stress–strain behavior of Polycrystalline Silicon Germanium (Poly-SiGe) is utilized effectively in this MEMS design to characterize the structure of the pressure sensor diaphragm element. The edge clamped elliptic structured diaphragm uses semi-major axis clamp springs to yield high sensitivity, wide dynamic range and good linearity. Integrated on-chip signal conditioning circuit in 0.18 μm TSMC CMOS process (forming the host substrate base for the SiGe MEMS) is also implemented to achieve a high overall gain of 102 dB for the MEMS sensor. A high sensitivity of 0.17 mV/hPa (@1.4 V supply), with a non linearity of around 1 % is achieved for the full scale range of applied pressure load. The diaphragm with a wide dynamic range of 100–1,000 hPa stacked on top of the CMOS circuitry, effectively reduces the combined sensor and conditioning implementation area of the intelligent sensor chip.     

Design of MEMS sensor for the detection of cholera and diarrehea by capacitance modulation

Microsystem Technologies - Cholera is caused by vibriocholera bacteria which were present in water or food. Diarrhea is caused by E. coli bacteria which were present in water or food. Bio-sensors...