基于视觉传感的激光-MIG复合焊熔透闭环控制

Vision system for closed-loop control of the penetration in laser-MIG hybrid welding

在对接焊中,坡口间隙的波动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。针对CO2激光-M IG复合对接焊,建立了基于视觉传感和DSP的熔透状态实时检测与控制系统,获取了清晰的熔池背面图像,经过适当的处理得到了熔池背面熔宽的信息,并通过调节焊接速度或控制电弧电流,对熔透状态进行了控制。结果表明:即使在间隙明显波动的情况下也获得了熔透可靠、背面熔宽均匀的焊缝,从而实现了复合对接焊熔透状态的闭环控制。

Real-time detection and control of penetration is needed to ensure steady weld penetration with even as the penetration status changes with variations of the gap width in butt joined welding. A penetration status detection and control system was developed based on vision sensors and digital signal processing for CO2 laser-MIG hybrid welding with gapped butts. Clear backside images of the molten pool were obtained and analyzed to measure the backside widths of the molten pool. The penetration status was controlled by adjusting the welding speed or the arc current. Tests show that even with significant gap width variations, steady penetration and weld depths with uniform backside widths are .obtained by the closed-loop control of the penetration in gapped butt hybrid welding.