Intelligent control of materials processing

This paper reviews the application of the techniques, for example fuzzy control, model- and rule-based control, qualitative reasoning and plan execution monitoring, associated with intelligent control, to the processing of materials by discrete manufacturing processes. Such solutions are used where the complexity of the manufacturing process cannot be accommodated by engineering design or the inclusion of an operator in the control loop. This is particularly important, from a commercial viewpoint, where the control of material variability and process flexibility are desired. The paper considers systems to control variations in the output attributes of the process due to inhomogeneous input material or process defects and to assist the set-up process. It also considers systems to control the microstructure of the finished product and to reduce the cycle times associated with open loop process recipes. Operation of such systems is a complex sensing and control task which frequently includes the necessity to control the manufacturing properties of the material and, in some cases, the evolution of its microstructure. A hierarchical framework for the control task in intelligent materials processing is summarised