基于ACFM技术的焊缝跟踪传感器空间磁场建模

Space magnetic field modeling of seam-tracking sensor based on alternative current field measurement

针对窄间隙I形坡口对接焊缝因其结构特殊性而缺乏直接有效的跟踪方法这一难题,设计了一种基于交流电磁场检测(ACFM)技术的新型焊缝跟踪传感器.建立了传感器焊缝表面感应电流的三维空间简化磁场模型,推导出了空间磁场磁感应强度计算解析式,利用MATLAB软件分析了三维方向的磁感应强度分布规律,重点分析工件焊缝引起的磁场畸变信号与焊缝位置之间的内在联系,采用近似二次多项式曲线拟合表征垂直焊缝方向磁感应强度Bz与焊缝左右偏离距离两者的数学关系,提出了一种新的焊缝偏差检测方法,为I形对接坡口焊缝自动跟踪系统的设计提供理论依据.

A new type of seam-tracking sensor was designed based on alternative current field measurement in order to provide effective tracking of narrow-gap I-type groove butt weld.A 3D simplified model of magnetic field was developed to simulate the generation of inductive current on the weld surface by the sensor,the calculating formula of spatial magnetic induction intensity was derived,and the 3D distribution of magnetic induction intensity was simulated using MATLAB software.The relationship between the weld position and magnetic distortion signal caused by weld seam was analyzed,the mathematical relationship between the magnetic induction intensity of weld seam and deviation distance around weld seam was established with the approximate two polynomial curve fitting,and a new method to detect the deviation of weld seam was put forward.