A structured approach to the design and simulation-based testing of factory automation systems

In order to face the more and more frequent market changes, reliable and flexible factory automation systems have to be developed or reconfigured with reduced times and costs. Therefore, innovative development methodologies for the structured design and testing of industrial supervision and control systems are mandatory. In the present work a development methodology is presented, which uses the formal reference model proposed by the IEC 61499 international standard to design the modules of a factory automation system. Moreover, a closed-loop simulation based testing method is presented to verify the different hierarchic levels of the designed automation system in a modular way, following a bottom-up approach. Such a technique is implemented in the Matlab environment, using its toolboxes Simulink and Stateflow. Through the adoption of formal models that exploit the concepts of modularity, encapsulation and abstraction, the description of complex systems is simplified and model reuse is enhanced. Furthermore, by means of a simulation based testing method correctness is verified before final implementation and reliability is improved. In the paper an application example is also presented, where the design and testing of the automation system of a manufacturing cell for a furniture factory by means of the proposed framework is illustrated.