This paper reports an automated procedure for constructing a plant model for PLC simulation. Since PLC programs contain only the control logic without information on the plant model, it is necessary to build the corresponding plant model to perform the simulation. Conventionally, a plant model for PLC simulation has been constructed manually, which requires much effort and indepth knowledge of the simulation. As a remedy for this problem, we propose an automated procedure for generating a plant model from the symbol table of a PLC program. To do so, we propose a naming rule for PLC symbols so that the symbol names include sufficient information on the plant model. By analysing such symbol names, we extract a plant model automatically. The proposed methodology has been implemented and test runs performed.

With the aid of the powerful computational ability and software tools, we undergo rapid change in a whole product manufacturing process. In a traditional way, it took long time and cost to build real manufacturing line. The behind time change for the manufacturing process ends up with supplementing large amount of budget. Therefore early detecting the errors on manufacturing process saves quite a big amount of time and money. As a result, the need for plant simulations rises. When we simulate manufacturing line on a virtual environment, it is not easy to acquire 3D data. If we have 3D CAD data, we can reuse them for each tools, products and equipments for the manufacturing line. Even in this case, the size matters. The large size of CAD data makes it difficult for us to directly use CAD data for simulation. As the CAD data and simulation data differs in their own purpose, we can reduce the size of the CAD data without losing simulation purpose. In this paper we propose effective methods for reducing the size of the CAD data and re-using them for simulation, assuming the 3D CAD data are already available.