【作者】 罗怡；

【导师】 许先果；

【作者基本信息】 重庆大学 ， 材料加工工程， 2005， 硕士

【摘要】 本论文开发设计了基于USB型单片机C8051F320的弧焊参数虚拟仪器检测分析系统。本系统由硬件系统和软件系统两大部分组成,以焊接电流、电弧电压为数据采集信号源。文中对涉及到的USB2.0 通信协议、小波分析理论、人工神经网络理论进行了必要的阐述,对系统的硬件设计、软件开发和主要软件功能进行了详细的分析说明。硬件系统利用单片机C8051F320 构筑信号采集硬件核心,该型号单片机由美国Cygnal 公司推出,自带USB2.0 协议的USB 控制器,并集成A/D 转换模块,因此硬件电路设计更简便,可实现采集数据的高速、实时传输。采用这种硬件设计方案,其成本大大低于目前使用最多的插入式数据采集卡,并且充分发挥单片机开发性能优越,使用灵活的特点,具有USB 设备即插即用、热插拔的优点,便于实现嵌入式系统集成,与数字化焊机结合实现产品化。软件系统由下位机程序、USB 驱动程序和上位机程序组成。下位机程序即固件程序用C 语言开发;USB 驱动程序采用美国国家仪器(NI)公司提供的VISA(Virtual Instrument Software Architecture)软件包来自动生成,实现对USB 设备的控制;上位机程序即高级应用程序采用NI 公司推出的LabVIEW7.1 语言开发。LabVIEW 是一种图形化的编程方式,使程序编制更快捷、直观,且易于调试、理解和维护。整个系统具有信号实时采集、波形数据显示与回放、任意数据段截取、数据存储、打印输出等功能。本系统可实现的分析功能有最高至8 层小波消噪、弧焊过程特征信息的小波提取、瞬时U-I 图绘制、电弧电压概率密度分布图绘制、焊接电流概率密度分布图绘制、短路时间频数分布图绘制、燃弧时间频数分布图绘制以及电压、电流、短路时间、燃弧时间的均值、方差、标准差统计分析,在统计分析基础上运用人工神经网络技术评估焊接质量。可基本满足对弧焊过程电参数数据分析、指导焊接实验、生产的需要。本论文设计开发的弧焊参数检测分析系统成功实现了USB 型单片机与LabVIEW 开发平台的数据通信,并集成了两者的优势,使用方便,为焊接生产、试验提供了一套分析弧焊数据、预测焊接质量的高效系统。更多还原

【Abstract】 This paper developed a visual instrument system about arc welding parameters monitoring and analysis based on USB type MCU —C8051F320. The system is composed of hardware circuit and software system. The signal source comes from welding current and arc voltage. USB2.0 communication protocol, wavelet analysis theory and artificial nerve network theory involved are illustrated and the development of the system is clearly analyzed. Data acquisition system hardware core is based on C8051F320 which integrates USB controller of USB2.0 protocol and A/D unit. This hardware design is more convenient and the cost is lower than the design by general data acquisition card. It has the characteristic of Plug&Play of USB bus. The performance is excellent and easy to realize integration of embedded-system. Firmware, USB driver and advanced application program constitute software system. The firmware is developed by C language and the USB driver is automatically created by VISA (Virtual Instrument Software Architecture) which realized the controlling of USB fixture. Advanced application program is developed by LabVIEW language. The system possess the function of signal real time acquisition, wave curve redisplay, data save and curve print. The system have the analysis function of wavelet eliminate noise to 8 level, distilling characteristic information in welding by wavelet, instantaneous U-I curve, probability density distribution curve about welding current and arc voltage, frequence distribution curve about short-circuit cycle and arc cycle, parameters statistic analysis and based on which estimating welding quality by artificial nerve network. The system of arc welding parameters monitoring and analysis realized the data communication between USB type MCU and LabVIEW develop flat and provided a high efficiency and portable system about welding quality analysis and forecast for welding manufacture and experiment.更多还原