A SUGGESTION OF SIMULATION FRAMEWORK FOR VERIFING PLC PROGRAM & APPLICATION IN AUTOMOTIVE PRODUCTION LINE

Proposed in this paper is a framework of virtual plant model for verification of PLC program by conducting the virtual plant modeling and simulation. The proposed virtual plant model consists of three types of objects: the virtual device model (object model), the intermediary transfer model (functional model) and PLC program (dynamic model). For the implementation of the proposed virtual plant model, this paper employs the I/O model which is based on Automata and Discrete Event System Specifications (DEVS) formalism. By applying an example of the automotive assembly line, nine errors in the PLC code are found and have been revised. With the proposed approach, it will be helpful to reduce the ramp up or down time of the automated manufacturing system.