Accurate control of welding parameters, such as arc power and wire speed, is critical for successful and appropriate weld joint penetration. The thickness of components being welded is a key parameter in defining optimum arc power for successful penetration, but is not always known beforehand or well controlled in manual and automated welding operations. This paper presents a novel feed-forward, sensor enabled, arc process control strategy based on ultrasonic thickness measurement. An ultrasonic wheel probe, deployed simultaneously alongside the welding torch, enables plate thickness measurement when coupled with a low-latency thickness measurement algorithm deployed on a real-time controller. An automated GTAW fusion control strategy, based on wheel probe measured plate thickness, provides direct input control of arc current, welding torch travel speed and filler wire feed rate. A parametric relationship between ultrasonically measured sample thickness and key arc welding parameters for welding S275 mild steel samples of thickness between 4.1 mm and 6.1 mm was established and verified. It is demonstrated that the system can measure and derive plate thickness while adapting arc power in real-time, with sufficiently low-latency, to allow consistent weld seam and uniform penetration on variable thickness steel samples, which under normal open-loop circumstances lead to sample burn-through and excessive penetration.

精确控制焊接参数（例如电弧功率和焊丝速度）对于成功且适当地焊缝熔深至关重要。焊接部件的厚度是定义成功焊接所需的最佳电弧功率的关键参数，但在手动和自动焊接操作中，事先未必知道或控制得很好。本文提出了一种基于超声波厚度测量的新型前馈，传感器使能的电弧过程控制策略。与焊炬同时部署的超声波轮式探头与在实时控制器上部署的低延迟厚度测量算法结合使用时，可以测量板厚。基于轮式探针测得的板厚的自动GTAW融合控制策略可提供电弧电流的直接输入控制，焊枪行进速度和焊丝进给速度。建立并验证了超声测量的样品厚度与用于焊接厚度在4.1 mm和6.1 mm之间的S275低碳钢样品的关键电弧焊接参数之间的参数关系。结果表明，该系统可以在测量和导出钢板厚度的同时，以足够低的延迟实时调整电弧功率，从而在厚度可变的钢样本上实现一致的焊缝和均匀的熔深，这在正常的开环情况下会导致样品烧穿和过度渗透。