【作者】 尹力；

【导师】 洪波；

【作者基本信息】 湘潭大学 ， 材料加工工程， 2007， 硕士

【摘要】 焊接自动化是现代焊接的发展趋势,实现焊缝自动跟踪是焊接自动化的重要环节。本文主要研究旋转电弧脉冲GMAW焊焊缝自动跟踪技术,首先对脉冲GMAW焊的性能特点和研究现状、国内外焊缝自动跟踪技术以及传感器技术的发展动态作了简要介绍,重点研究了如下几个关键问题。研究了脉冲GMAW焊的电弧信号特点及其电弧自身调节作用过程,利用旋转电弧传感器的传感优点,通过调整传感器内部结构,成功获取规律变化显著的脉冲电弧传感信号。分析脉冲GMAW焊电弧传感信号的幅频特性,采用无限增益多路反馈二阶低通滤波器对电弧传感信号进行硬件滤波,并进行了硬件电路的抗干扰处理,避免各种干扰对跟踪系统的影响,保证焊缝跟踪的顺利进行。介绍了普通GMAW焊的电弧信号处理方法,并在此基础上提出了一种脉冲GMAW焊的信号处理方法——包络线取值法。通过对脉冲电流信号进行提取包络线处理,获取脉冲电流峰值和谷值,结合有限削波处理,可提取出较为准确、可靠的焊缝偏差信息,该算法具有算法简单、响应快、实现容易的特点。为了保证良好的焊缝跟踪效果,对偏差信号进行了PID控制算法处理,提高跟踪系统的准确性。完成了基于单片机系统的程序设计以及整个系统的联调,实现了旋转电弧脉冲GMAW焊的焊缝自动跟踪,并对焊缝自动跟踪实验结果进行分析和评价。实验结果表明焊缝跟踪效果良好,验证了本文所采用的软硬件相结合的处理方法的可行性,也验证了包络线取值法和有限削波处理方法以及PID算法在脉冲电弧信号处理中可行性。本文创新之处:系统研究了脉冲GMAW焊的电弧特性,提出了包络线取值法,为解决脉冲电弧的信号处理提供了参考依据,对脉冲GMAW焊技术的发展及其在电弧传感焊缝跟踪中的应用具有积极的推动作用。更多还原

【Abstract】 The welding automation is the development tendency of modern welding, and the auto weld tracking system is an important link of the welding automation. The main research of this text is the weld tracking technology of revolving arc sensor in GMAW-P, at first, a brief introduction of the performance characteristic and the present research situation of GMAW-P, and the development trend of domestic and foreign weld tracking technology as well as the sensor technology is made, and then mainly discussed several key problems as follows.Have studied the signal characteristic of the arc of GMAW-P and the arc own adjusting effect process, made use of the sensing excellence of revolving arc sensor, through modulating the internal structure of sensor, obtained the pulse arc signal which has distinct regular changes.Have analyzed amplitude-frequency characteristic of GMAW-P, used the two step low-pass filter with infinite filer and multiple feedback to carry on hardware filter to the arc sensing signal, and have carried on anti-jamming processing to hardware circuit. Used the method of the circuit to avoid the influence of interferer to the auto weld tracking system from various kinds of disturbing, guaranteed the tracking runs smoothly.It also introduced the method of the arc signal processing from the arc of common GMAW. Based on that, comes up with the method of getting numerical value from envelop, a method to dispose the signal for GMAW-P. Worked on the signal of pulse current with that method, got its crest value and its lowest, and combined the way of cutting the signal limitedly, it can get much more veracious and credible information about the deviation of the welding seam. The method owned the trait that calculating simply, responding swiftly and easy to carry out. In order to guarantee the good weld tracking effect, the weld deviation signal has been carried on PID processing to enhance the accuracy of tracking system.Accomplished the program design and the adjustment of the whole system which were based on the system of the single chip computer, carried out the auto weld tracking about the revolving arc sensor in GMAW-P, additionally, analyzed and evaluated the results from the experiments of the auto weld tracking. The experiments showed all right, validated the feasibility of the method of combining the hardware and software working, and the method of getting the numerical value from envelop and the way of cutting pulse limitedly and the PID processing, which were used in pulse arc signal processing.The innovative place of this article: has studied the arc characteristic of GMAW-P systemically, and comes up with the method of getting numerical value from envelop, which supplied a reference for settling the problem about pulse arc signal processing. It promotes greatly that the development of GMAW technology and its application in arc sensing weld tracking.更多还原