水浸超声扫描检测系统的设计

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中北大学学位论文
水浸超声扫描检测系统的设计 摘 要
弹体内部装填火药，是由整体铸造和切削技术加工成型。由于制造水平的局限 性，弹体可能会出现划痕、气孔、分层等缺陷。因此，研制一套水浸超声扫描检 测系统对弹体的大批量生产进行实时评估，不仅能够提高生产的质量，更重要的 是能够消除安全隐患，具有重要意义。 本课题以超声无损检测为基础，根据弹体标准样件的结构特点和缺陷类型，采用了 超声底波回波法和超声缺陷反射回波法的多探头在线检测方法， 设计了四通道超声处理 系统。系统具有超声发射接收、限幅、压控放大、双峰检波、闸门控制和峰值保持等功 能。开发了基于 ISA 总线的超声数据采集卡，以 EPM9560 为逻辑控制核心，对超声处 理系统进行控制，并将采集到的数据存储到 FIFO 中。利用 WinDriver 开发了采集卡驱 动程序， 采用 SC303F 步进仿形控制器对机械系统运行进行编程控制。 开发了基于 Visual C++ 6.0 的超声在线处理软件，能够对超声数据采集卡进行参数设置，通过闸门控制、 滑动平均滤波和阈值法对缺陷信号进行处理、显示，并对检测结果进行保存打印。针对 系统特定的工作环境，提出了一系列抗干扰措施，效果明显。利用本系统对工厂大批量 产品进行了在线检测，性能良好。 最后，对本系统的进一步扩展提出了可行的建议。 关键词：弹体，水浸超声，噪声干扰，ISA 总线
王建民
2012 年
6
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6
日
原 创 性 声 明
本人郑重声明：所呈交的学位论文，是本人在指导教师的指导下，独 立进行研究所取得的成果。除文中已经注明引用的内容外，本论文不包含 其他个人或集体已经发表或撰写过的科研成果。对本文的研究作出重要贡 献的个人和集体，均已在文中以明确方式标明。本声明的法律责任由本人 承担。
3.3 超声发射接收卡及相关电路的设计 .........................................................................15 3.3.1 超声发射电路 ..................................................................................................15 3.3.2 超声限幅及衰减电路 ......................................................................................15 3.3.3 超声压控放大电路 ..........................................................................................16 3.3.4 双峰检波电路 ..................................................................................................17 3.3.5 闸门控制电路 ..................................................................................................18 3.3.6 峰值保持电路 ..................................................................................................18 3.4 数据采集卡的设计 ....................................................................................................19 3.4.1 主控芯片EPM9560 简介 ................................................................................20 3.4.2 ISA总线简介及接口模块的设计 .................................................................20 3.4.3 触发模块的设计 ..............................................................................................23 3.4.4 3.4.5 A/D转换模块的设计 .....................................................................................24 FIFO存储模块的设计 ..................................................................................27
中北大学学位论文
目
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第 1 章 绪论 ..............................................................................................................................1 1.1 选题背景及研究意义 ..................................................................................................1 1.2 研究现状 ......................................................................................................................1 1.2.1 超声检测方法研究现状 ....................................................................................1 1.2.2 信号处理研究现状 ............................................................................................3 1.3 本课题的主要研究内容 ..............................................................................................4 第 2 章 水浸超声扫描检测系统检测方法及原理 ..................................................................6 2.1 系统检测对象简介 .......................................................................................................6 2.2 超声探头的选择 ..........................................................................................................7 2.3 超声检测方法的选择 ..................................................................................................8 第 3 章 水浸超声扫描检测系统硬件平台的构建 ................................................................12 3.1 系统检测总体方案 ....................................................................................................12 3.2 ZBCT_04 数字超声处理系统 ................................................................................13
中北大学学位论文
Design Of Water-logging Ultrasonic Scanning and Testing System Abstract
Projectile bodies filled with gunpowder are molded by whole casting and cutting craft. As result of the limitation of manufacture procedure, flaw types such as scratch, pore and layering etc may be produced. Therefore, a set of water-logging ultrasonic scanning and testing system is required for mass production of projectile bodies. The system can not only improve production quality, but also eliminate security risk, which has significant value. According to the structural features and flaw types of projectile bodies’ standard sample, and based on the ultrasonic nondestructive testing technology, a set of 4-channels ultrasonic processing system is designed adopting ultrasonic bottom wave echo method and flaw wave echo method. The system has the functions of ultrasonic transmitting and receiving, amplitude limiting, voltage controlling, detecting, gate controlling and peak holding, etc. A data acquisition card based on ISA bus is developed taking EPM9560 as the logical controlling center. The card could control the ultrasonic processing system and save the acquired data into FIFO. The driver of the card is developed with WinDriver. The mechanical system is controlled by programming with stepping contouring controller SC303F. The ultrasonic online processing software is developed based on Visual C++ 6.0.The software could set parameters of data acquisition card, process and display acquired data using the methods of gate-controlling, sliding average and threshold. Besides, the testing data could be saved and printed by the software. A series of anti-jamming measures are proposed according to the special working environment and excellent effects have been received. The system has been used to detect mass products in factory and good results have been received. At last, some feasible suggestions are proposed for the further extensions of the system. Keywords: Projectile bodies, Water-logging ultrasonic, noise jamming, ISA bus