【作者】 卢胜男；

【导师】 赵祥模；

【作者基本信息】 长安大学 ， 交通信息工程及控制， 2007， 硕士

【摘要】 超声波无损检测技术由于具有穿透能力强、对人体无害、应用范围广、检测深度大、缺陷定位准确以及成本低等优点,已成为国内外普遍采用的无损检测技术。纵观目前国内外大量使用的混凝土超声检测设备,其采样位数一般为8位,采样频率最大20MHz,可以进行单通道或双通道数据采集,采样精度和工作效率都比较低。同时,常规的混凝土超声检测设备只能对所接收的一维信号进行分析处理和人工判读,可靠性较差,人为因素对检测结果的影响较大。因此,结合本项目,自行研制开发了稀土换能器,并设计和实现了配套的混凝土超声成像检测系统。本课题的主要目的就是对该混凝土超声成像检测系统的硬件平台进行设计和研究。本文在综合分析研究目前国内外混凝土检测系统结构原理的基础上,提出了一种新的网络化混凝土超声检测仪的结构,详细讨论了该混凝土超声检测仪器应满足的功能要求和性能指标。在深入研究CPLD技术、嵌入式Internt技术、数据采集和信号处理等技术的基础上提出了以网络处理器加CPLD为核心,由网络处理器完成网络传输、数据采集功能,信号处理由相应的外围电路来实现,数据采集、信号处理与网络协议处理并行运行的系统构成方案,深入研究了多通道并行采集系统的结构,设计了适合该仪器24路数据并行采集的电路结构。使用CPLD开发环境完成了硬件平台各功能模块之间的逻辑连接和仿真,深入学习和研究网络处理器IP2022硬件结构、操作系统和集成开发环境的基础上,开发了超声信号采集仪的底层通信程序。最后,通过对系统的实测试验表明,本文提出和设计完成的混凝土超声检测系统的硬件平台能够满足课题所提出的基本功能要求,并具有较强的抗干扰能力。更多还原

【Abstract】 The technology of ultrasonic nondestructive testing has been widely used because of its characteristics of good penetrability,harmless to people, widely used,great testing depth and low cost.Up to now, the ultrasonic instrument for concrete testing ,which widely used at home and abroad,has 8bit sampling digits and 20MHz sampling frequency,and collects data from one channel or double channels.At the same time,the testing method has been based on one-dimension signals, from which it is hard to get a clear description on the concrete structures. So a new ultrasonic testing system has been developed,which is suitable for new designed rare earth GMM transducer.The main purpose of this paper is to the design and realization of the ultrasonic instrument used for concrete testing.Based on analysing the structure of ultrasonic testing system,the paper brings forward a new networked ultrasonic system used for concrete testing.and discusses its functions and capability targets. The core of the new instrument is composed of network processor and CPLD.The functions of network transmission and data acquisition are finished by network processor,and the function of signal processing is completed by peripheral circuit.Data acquisition, signal processing and network transmission can be processed simultaneously.Besides, the logical connection and emluator among functional modules of hardware platform is finished by CPLD IDE,and the communications software is implemented by IP2022 IDE.At last,Experimental result shows that this system can reach the required standard,and the ability to resist disturbance is strong. So it can be used for the concrete construction safety supervision and quality evaluation.更多还原