基于USB的机车故障检测记录仪数据传输技术

针对当前机车故障检测记录仪所存故障的快速提取需求，结合USB接口的结构、特点，介绍基于Cypress EZ-USB2131的USB软硬件系统的开发方法，阐述该系统在机车故障检测记录仪中的应用。从实际的检测记录仪装车运行效果可以看出，USB接口技术能够为车载设备信息的提取提供高速可靠的连接，满足实际需求。     

120km/h提速货车可靠性试验研究

通过对120km/h提速货车可靠性试验中收集的大量故障数据进行统计分析,根据18万km的阶段试验数据分析与推断,利用可靠性工程的理论,对货车提速到120km/h运行的可靠性,做出初步的结论性判断,并提出了今后在铁路车辆设计、制造、试验及维护保障管理等各方面,全面引入产品可靠性质量管理理念,进行相应的可靠性深入研究。     

乌鞘岭特长隧道F7断层围岩大变形段二次衬砌安全度分析

乌鞘岭特长隧道11#斜井处正洞在穿越F7断层时,由于隧道埋深大,断层岩体破碎,岩体完整性差,围岩自稳能力弱,受挤压影响等,开挖后围岩变形长时间不收敛,50d后的变形仍有2—4mm/d,累计最大变形量已超过60cm,部分地段严重侵限,不能满足《铁路隧道设计规范》关于二次衬砌施做的规定。如果二次衬砌及时施做,在软岩大变形条件下其安全度问题值得进一步探讨。本文通过现场量测和监测手段,并结合理论计算与分析,对已施工完毕的二次衬砌段的结构安全度进行了探讨,结果认为,目前乌鞘岭隧道F7断层二次衬砌结构的设计参数是可行和安全的,满足《规范》所规定的在软弱围岩地段的要求,建议及时施做二次衬砌。     

奥迪A6轿车防盗系统工作原理与检修

介绍奥迪A6轿车防盗系统的工作原理及控制系统电路,详细总结其故障检修方法及部分故障代码。     

真空助力制动系统故障诊断方法

以带真空助力的液压制动为例，介绍几类制动故障模式的诊断方法、发生故障的原因及部位。     

网络故障受理平台的设计

研究目的：为提高网络的效率，对网络故障进行诊断，设计出网络故障受理平台，当网络出现问题时，适时地通知管理者进行故障排除，调整网络配置，从而有效地改善业务运行环境和运行状况，提高客户的满意程度。 研究方法：PHP是一种服务器端的HTML脚本／编程语言，是建立动态网站的强大工具。而MySQL是一个精巧的SQL数据库管理系统，可运行在多种平台上，本系统采用php＋mysql的组合对系统进行开发设计。 研究结果：开发出网络故障受理平台的网站，本网站可提供同时几百人的浏览并保证速度正常。 研究结论：利用PHP＋MySQL组合工具开发设计的网络故障受理平台界面简单、功能全面、可扩展性好，分为故障发生、确定发生故障的用户、登记故障问题、诊断分析、通知处理、回访结果、故障完成等环节，可减少网络故障发生机率、缩短网络故障处理时间、提高网络工作效率，满足可靠性、灵活性、开放性、安全性的设计原则。     

Fault detection of vehicle suspension system using wavelet analysis

This paper presents a method based on continuous wavelet transform to detect the faults of vehicle suspension systems. The Morlet wavelet functions are employed to approach the natural frequencies of the system and the frequency components of the signal with relative maximum energy. To evaluate our method, we use a full vehicle dynamic model which has been simulated in ADAMS/CAR and validated by laboratory test results. The suspension faults have been considered due to the damage of shock absorbers (dampers) and upper damper bushings (UDBs) and assumed as the decrease in damping force and loose joints, respectively. In this paper, the incapability of the spectral analysis by using fast Fourier transform in analysis of the signals is revealed through applying the inputs that include transient characteristics and then wavelet transform employed to achieve more proper results. A swept frequency is applied as an input to the wheels that simulates the road irregularities. After detection of faulty sections of the system using signal energy distribution, the defects of damper and UDBs are distinguished from each other through observing the changes of natural frequencies and corresponding energy amplitudes.     

网络通道维护经验探讨

网络故障诊断以网络原理、网络配置和网络运行的知识为基础,网络通道检测工作对维护人员的技术水平和相关专业知识掌握有较高的要求,为此对网络通道维护经验进行总结,以便交流和提高。     

Application of observer-based fault detection in vehicle roll control

This paper describes how observer-based techniques for intelligent fault detection were applied to monitoring an active suspension control system in an experimental articulated heavy vehicle. The aim was to define a practical method for detecting faults, taking into account the nonlinearities of the vehicle. The experimental vehicle was divided conceptually into subsystems, namely the passive dynamics of the trailer, the dynamics of the hydraulic actuators, and the expected response of the closed-loop system. A linear dynamic model was designed for each subsystem. A fault detection observer was then designed for each dynamic model. The observer feedback gains were chosen to optimise estimation by the observer residual of specified errors on the output measurements. The observer residuals were then normalised and combined logically to provide a fault diagnosis. The performance of the fault detection scheme is demonstrated in the case of sensor faults and changes in the operation of the active control system.     

JL-902型机车柴油机燃烧系统分析仪的研制及应用

讨论了JL-902型机车柴油机燃烧系统分析仪的系统组成、结构特点、现场测试数据,并对数据进行了分析和讨论。通过对测试的示功图和高压油管压力波的分析能够得出柴油机燃烧系统的基本性能参数,并为柴油机提供了一种新的测试设备。