Mirror synthesis in a mechatronic system for superficial defect detection

This paper deals with the problem of defect detection on highly reflective surfaces making use of vision systems. A new mechatronic system has been developed, based on a nonflat mirror. According to the method described in this paper, the light rays emitted from a source hit a suitably designed nonflat mirror, and are reflected so as to illuminate the curved surface under investigation. The path of the light rays from the source of light to the mirror and then to the object surface is mathematically traced making use of the optical geometry laws. After the reflection on the object surface, the light rays are collected by a charge-coupled device (CCD) camera and elaborated by a vision system, which manages to detect the surface defects as shadows of various shape and size within the picture. Simulations have been carried out in order to provide the optimal mirror shape. Moreover, a prototype of the mechatronic system, including the synthesized mirror, has been built to perform some experimental tests to validate the method. The results, reported in the paper, definitively show the effectiveness of the proposed method.     

汽车制动性评价及制动距离效果分析

汽车在行驶过程中会有一定的动能,随着汽车行驶速度不断提高,为了使行驶速度降低或者停车,就必须对汽车施加一个相反的阻力,驾驶员要根据交通情况来对制动力进行控制,来实现车辆停止的强制制动,汽车的制动功能是汽车的主要功能,而汽车的制动效能是汽车在生产及使用过程中的最基本评价指标.     

一种便携式故障检测系统的设计

供输弹机是武器上易发生故障的子系统,以往的故障检测设备体积庞大。针对这一问题,以某型火炮的供输弹机为对象,结合数据采集的思想,提出了一种基于嵌入式PC104控制总线的便携式故障检测系统。论述了该系统的工作原理,硬件设计,并阐述了基于Visual C++开发工具的系统软件实现。试验表明,该检测系统在保证供输弹机运转的同时,能够快速检测弹丸输送中的多路信号,为准确定位供输弹机的故障,提供了有效的解决方案。     

远程检测技术在故障诊断系统中的应用

针对装备故障诊断系统,建立用于远程故障诊断的远程检测点信息传输模型。采用数据绑定的方法来传输中心站或者各装备端的控制指令信息,利用远程面板技术来实时传输各个仪器的实时运行界面,利用数据抽取的方法来减小波形传输的数据量,最后在LabVIEW软件开发平台下实现了上述功能。     

浅析电力系统继电保护及故障检测

电力系统继电保护装置是电力系统安全稳定运行的重要基础,更是电力系统故障的第一道防线。随着近年来电力系统的加速发展,电力系统中出现的故障问题也日益严重。本文结合相关资料和文献分析电力系统继电保护及故障检测的重要作用,并对故障检测方法进行了简单介绍。     

基于单片机的短距离电缆故障检测系统设计

针对目前10m以内电缆出现故障时,难以精确检测及查找等问题,提出了一种基于单片机的线路故障点检测系统。设计了单片机控制双臂电桥测量低电阻电路、多谐振荡测量电容电路、辅助调平电桥电路、输出显示等电路。对电话线进行了实际测试,测试结果表明,该系统在10m以内线路出现短路和断路故障时,能给出准确的定位,并且具有较高的精度和稳定性,其中短路距离平均误差小于1%,断路距离平均误差小于15%。     

以观测器为基础的量化网络化系统故障检测

文中针对具有未知输入和不确定扰动信号的系统,研究一类以观测器为基础的量化网络化系统故障检测问题。首先,引入时变量化器,对输出信号进行量化处理,在此基础上,对原系统建立故障检测滤波器,通过比较原系统与观测器的输出,建立故障检测滤波器误差系统。最后,基于H∞稳定性理论,将故障检测滤波器问题转化为问题。在论证过程中结合LMI有关定理,给出仿真实例,验证文中方法的有效性。     

基于信号提纯的机械故障检测系统设计

运用传统机械故障检测系统对机械进行检测时,未对通道信号进行分离和提纯处理,检测结果误差较大。针对上述问题,设计一种基于信号提纯的机械故障检测系统。该系统主要包括主控单元、信号提纯模块和人机界面,通过主控单元的PC104控制总线、信息采集卡和信号转换调理器获取符合电气标准的初始运行信号,再利用信号提纯模块实时管控、信号管理、运算控制、存储控制等功能对初始运行信号进行分离、提纯。系统软件设计数据采集流程通过数据采集卡初始化、A/D变更和确立仿真输入通道获取故障检测流程的基础数据。在此基础上,通过故障检测流程的动态检测方法实现机械故障检测。实验结果表明,所设计系统获取的故障信号误差为0.08～0.34,不同故障检测准确率均在97%以上,说明该系统稳定性高、实用性强。     

基于JAVA的软件故障自动检测系统设计

为了提高软件的故障自动检测能力,进行软件故障自动检测系统优化设计,提出基于JAVA的软件故障自动检测系统。系统由软件故障数据采集模块、故障信息融合模块、特征提取模块、信息集成处理模块和故障专家系统诊断模块组成。在DSP和逻辑PLC中进行故障检测系统的集成开发。采用数据融合滤波技术进行软件故障信息的多传感器采集,对采集的故障采用自适应功率放大进行信息增强处理,提高故障的类别属性诊断能力,在故障信息融合中进行故障特征挖掘,提取反映软件故障类别的关联特征量,在专家系统进行故障识别和智能诊断。在JAVA开发工具下进行软件故障自动检测系统的模块化开发设计。测试结果表明,设计的软件故障检测系统具有很好的故障诊断能力,故障检测的准确率较高。     

Data-driven design of robust fault detection system for wind turbines

In this paper, a robust data-driven fault detection approach is proposed with application to a wind turbine benchmark. The main challenges of the wind turbine fault detection lie in its nonlinearity, unknown disturbances as well as significant measurement noise. To overcome these difficulties, a data-driven fault detection scheme is proposed with robust residual generators directly constructed from available process data. A performance index and an optimization criterion are proposed to achieve the robustness of the residual signals related to the disturbances. For the residual evaluation, a proper evaluation approach as well as a suitable decision logic is given to make a correct final decision. The effectiveness of the proposed approach is finally illustrated by simulations on the wind turbine benchmark model.     

基于深度学习的电力设备红外与可见光图像配准

针对相对位置固定的红外和可见光双目相机配准任务,现有算法没有考虑到两者相对位置固定的先验知识,存在配准精度低、几何定位差异大等问题,适用性差。提出一种基于几何约束下区域搜索的红外可见光双目图像配准方法。首先借助红外和可见光双目相机的标定信息对红外和可见光图像进行立体校正使二者处于同一高度之上。接着借助于相位一致性计算红外与可见光的边缘特征图,然后在红外边缘图上提取特征点,最后提出两阶段的同名特征点搜索方法,以红外特征点为基准在可见光边缘图局部区域内搜索同名特征点。在第一阶段以归一化互相关（Normalized cross-correlation,NCC）为相似性度量计算两边缘图的整体水平偏移,预测同名特征点初始位置,在第二阶段提出多尺度加权NCC作为相似性度量,在初始同名特征点位置周围精确搜索同名特征点。在构造的真实环境数据集上进行实验,实验结果表明相对于其他对比算法,在特征点匹配数量和准确率以及主观视觉上的配准效果都优于其他对比算法。     

A mechatronic sensing system for vehicle guidance and control

Magnetic sensing is used for control and guidance in intelligent transportation systems (ITS). This includes vehicle applications such as lane-keeping in intelligent cruise control as well as driver assistance in highway maintenance functions such as snow removal. This paper presents a new mechatronic magnetic sensing system for ITS. The new system has several advantages both in terms of its hardware design and its underlying reference detection algorithms, providing a significant improvement in performance, maintainability, and upgradability over existing systems. It is a mechatronic system in that it combines mechanical position sensing with electronics implementation of the hardware and the underlying algorithms.     

双向全桥DC-DC变换器故障智能检测系统设计

传统DC-DC变换器故障检测系统只对变换器中某重要元器件进行故障检测,导致检测结果不准确。为此,设计了新的双向全桥DC-DC变换器故障智能检测系统。通过闭环霍尔电流传感器对电流信号进行采集,给出信号采集电路,通过分析双向全桥DC-DC变换器元件衰减过程提取故障数据,对不同故障状态样本进行采集,构建HMM模型,求出HMM模型初始参数,迭代参数直至其收敛到既定区间,对采集的电压、电流信号进行归一化处理,产生观察值序列,把观察值序列输入到训练完成的不同HMM模型中,求出相似或然率和相似或然率最大值相应的HMM模型,即为双向全桥DC-DC变换器故障检测结果。实验结果表明所设计系统检测准确性高。     

基于新型故障搜寻策略的检测系统设计

为了达到复杂系统快速故障搜寻的目的,设计了一种基于二元决策图优化的新型故障搜寻策略的检测系统设计。通过对基于二元决策图优化的故障搜寻方法研究和实际的硬件电路设计,最终实现了检测系统的软硬件设计。使用这种方法能够很好的实现故障诊断系统在嵌入式平台的开发,并能够取得较好的诊断效果。     

A fuzzy expert system for fault detection in statistical processcontrol of industrial processes

Little work has previously been reported on the use of fuzzy logic within statistical process control when this is used for fault detection as part of quality control systems in industrial manufacturing processes. Therefore, the paper investigates the potential use of fuzzy logic to enhance the performance of statistical process control (SPC). The cumulative sum of the deviation in the monitored parameter is combined with the deviation in an attempt to discriminate between false alarms and real faults and, consequently, to improve the quality of the solution. Combinations of control rules are utilized and trained to cope with different inputs such that rejection of false alarms is achieved and quick detection of real faults is obtained. The design and implementation of this fuzzy expert system (FES) are presented, and a comparative rule based study is performed     

Data-mining based fault detection

This paper presents a fault-detection method based on the phase space reconstruction and data mining approaches for the complex electronic system. The approach for the phase space reconstruction of chaotic time series is a combination algorithm of multiple autocorrelation and Г-test, by which the quasi-optimal embedding dimension and time delay can be obtained. The data mining algorithm, which calculates the radius of gyration of unit-mass point around the centre of mass in the phase space, can distinguish the fault parameter from the chaotic time series output by the tested system. The experimental results depict that this fault detection method can correctly detect the fault phenomena of electronic system.     

Assessment of mechatronic system performance at an early design stage

For conceptual design of electromechanical motion systems, an assessment method is formulated that supports the design of a feasible reference path generator, control system, and electromechanical plant with appropriate sensor locations, in an integrated way. This method is based on a classification of standard transfer functions, plant models, and closed-loop systems. The assessment method can be applied in several ways, depending on the available knowledge about the design problem. In order to illustrate this method, an application to an industrial motion system is described. The assessment method quickly provides insight in the design problem. Furthermore, feasible goals and required design efforts can be estimated at an early stage.     

基于Compact PCI总线的多通道通信故障检测系统设计

针对现有多通道通信故障检测系统检测性能弱、效率低、比特误差率偏高的不足,提出一种基于Compact PCI总线的通信信号故障检测系统。给出Compact PCI总线通信故障检测机制,并基于此设计了检测系统的硬件平台及软件算法。通信故障检测系统的硬件部分由Compact PCI总线架构、信号采集模块、主控芯片、总线控制器及部署在终端的网络工作站组成,分别介绍了各模块的特征及基础功能;在软件算法流程上选用了通用性更好的二次相关算法,能够在低信噪比的条件下准确预估出通信网络时延,并提取出多通道通信故障信号中所包含的异常信息。最终的测试结果显示,提出系统的检测效率更高,在同等测试条件下可以得到更低的比特误差率。