A methodology of CAPP/CAP systems integration based on a product intermediate state representation

The proposed idea of the integration methodology is based on the two basic pillars it is the modified functional model of the manufacturing process plan and a product intermediate states representation. The product state in certain moment of the manufacturing process can be identified by a set of states which describe the current status of the manufacturing process advance for particular manufacturing features. On the other hand from a manufacturing process nature results that during its course a product can be at one of the following states after rough, medium and finishing manufacturing treatment. Information about product states makes the full integration between CAPP and CAP systems possible. The proposed methodology allows reacting to unexpected production process disturbances. In this case the CAP system in cooperation with manufacturing execution system MES, which collects production data just from PLC’s controllers, communicates with CAPP system in the feedback loop and sends a set of the product intermediate states. Base on this description the CAPP system redesign a manufacturing process plan taking into account the current product state. In the paper the modified functional model of the technological process plan and the method of product intermediate states are presented. Moreover the proposal of the functional schema of the integrated CAD/CAPP/CAP environment is shown.