Sampled weighted attraction control of distributed thermal scan welding

This article addresses the problem of distributed-parameter control for a c lass of infinite-dimensional manufacturing processes with scanned thermal a ctuation, such as scan welding. This new process is implemented on a roboti c GTAW laboratory setup with infrared pyrometry, and simulated by a flexibl e numerical computation program. An analytical linearized model, based on c onvolution of Green's fields, is expressed in multivariable state-space for m, with its time-variant parameters identified in-process. A robust control ler design compensates for model uncertainty, and a sampled weighted attrac tion method is introduced for heat source guidance based on real-time therm al optimization of the heat input distribution. The distributed thermal reg ulation strategy with infrared feedback is validated both computationally a nd experimentally in scan welding tests.