基于熔池背面图像的薄壁筒体熔透自整定PID控制系统  

Self-tuning PID control of welding penetration in thin-walled cylinder based on rear molten pool image

作　　者：代克杰[1,2] 王勤[3] 赵丽[1] 曾申波[1] 张富巨[1] 

机构地区：[1]武汉大学动力与机械学院,湖北武汉430072 [2]平顶山学院电气信息工程学院,河南平顶山467000 [3]苏州热工研究院有限公司在役检查中心,江苏苏州215001

出　　处：《控制理论与应用》2011年第3期395-399,共5页Control Theory & Applications

基　　金：科技部科技型中小企业技术创新基金资助项目(09C26214204829)

摘　　要：在薄壁筒体环缝焊接中,工艺参数及坡口尺寸的波动都会导致焊接熔透状态的变化.为保证稳定的熔透,需要对焊接熔透状态进行实时检测和控制.本文针对薄壁筒体环缝钨级惰性气体保护焊(TIG焊),建立了基于视觉传感的直接传感法,获取了清晰的熔池背面图像,经图像处理得到了满足熔透要求的熔池背面熔宽范围,并通过自整定PID控制器实时调节焊接速度对熔透状态进行自适应控制.结果表明:该方法提取熔透状态信号可靠,基本消除了熔透状态间接传感法的控制盲区.The fluctuations of process parameters and groove dimensions lead to the variations of weld penetration of the girth welding for the thin-walled cylinder. In order to ensure a stable penetration, the penetrations are needed to be detected and controlled in real-time. A vision-based direct-sensing equipment is installed for the thin-walled cylinder TIG（tungsten inert gas） welding to obtain a clear rear pool image. The processed image gives the rear width-range of the melt pool for desired penetrations. A self-tuning PID controller controls the penetration by properly adjusting the welding speed, Experiment results show that the penetration signal obtained by this method is reliable, practically eliminating the insensitive zone in indirect sensing.

关 键 词：薄壁筒体环缝 熔透状态 背面熔池图像处理 自整定PID 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]