PROCESS CHAIN SIMULATION : VIRTUAL REALITY TO MACHINE-VR2M

The networking of production processes by means of information technologies (IT) has become a major field of development within industry and research. The main target is to interlink autonomous production systems to an intelligent production line, where products itself organise and control their manufacturing. This new attempt in production is -actual in Germany described under the definition "Industry 4.0", the fourth industrial revolution. Basically, the essential hardware and software to meet this objectives has been developed in other branches and is able to upgrade machines and handling systems to cyber-physical systems. The crucial issue to design an autonomous, intelligent production line is to generate the exact process data for each production step, to verify this data and to transfer it into the individual machine control. The characteristics of this main problem increases with the degree of interactions between the processes in the production line. In the woodworking industry, the process chain of profiling has a high degree of interactions. The individual production steps are strictly based on another and the result of a process effects the subsequent one respectively. To network these processes and add IT, an integrated IT system with individual CAD/CAM system for each process type is needed. The estimation of the interactions is done by the simulation of the whole process chain in a virtual reality before the real production. This enables to verify the process data, and to benefit from simultaneous engineering. Besides the essential algorithms to calculate the process data for the different process types and estimate the geometry corruptions due to systematic errors and manufacturing tolerances, the consideration of the material behaviour during the production is the determining factor to get valid data for the process chain. The shrinking and swelling of wood and woodbased materials due to a change of moisture content causes a geometry corruption and requires algorithms to simulate this behaviour in the virtual real ity. The result of these algorithms for the processes and the material behaviour are the exact process data for a specific profile. The database for the calculations and the data storage is a developed product data model. This product data model forms the gateway for the simulation in the virtual reality to the machine controls.