A control model for multi-products processing

Time-critical systems are characterized by operation times included between a minimum and a maximum value. An acceptable behaviour depends not only on the logical correctness of the task sequence but also on the time at which the operations are performed. So, a specific control is required. In this paper, the robustness property is used to build a time schedule of when the manufacturing system is to process several kinds of parts. This approach uses a p-time Petri net as its modeling tool and considers the multi-processing case as a disturbed mono-processing one. To make a more succinct and manageable description of the obtained control, p-time coloured Petri nets are defined. A typical illustration of an electroplating line is given.