Copyright @ IFAC New Trends in Design of Control Systems. Smolenice. Slovak Republic. 1994 SPECIFICATION, ANALYSIS AND VALIDATION OF DISTRIBUTED CONTROL SYSTEM: THE ACSY -R MODEL V.CHAPURLAT*, F.PRUNET* *LIRMM - Labontoire d'lDformatique, Robotique et Micro-elcctrooique de Montpellier - UMR 9928 - Universite MOIIIpellier IIICNRS - 161, rue ADA - 34392 MOIIIpellier Cedex S Phone.: 6741 8S 81 emaiI : c:hapurIaI@limun.fr Fax: 6741 8S 00 pnmd@1imun.fr AIIm1Ict: We present in this paper an intcrgraIed CASE model for the control part design, the architecture design and the validation of the operational arcbitecture obtaiDed by merging control part and architecture part. The control design is based on a set of functional, behavioural and data processing models. The architecture design allows to model the diffcrmt equipments used. It is based on an object oriented model using the Interpreted Petri nets for the behavioural IpeCification. The validation is supported with a qualitative and quantitative analysis of the operational an:I!itec:tuR. A IOftware tool is yet developped and praeutcd at the end of the paper. Key Words: CAD, Modeling. Control Engineering. Decentralized control, Distributed control, Functional Analysis, Manufactoring processes, Computer An:hitec:ture 1. INTRODUCTION The whole life cycle of a control part system is composed by a set of activities: software and hardware specification, software and hardware design, validation, operational implementation and maintenance. It is covered by a set of models, methods and tools which can't really collaborate like the user wants them to. So, we propose in this paper, an integrated CASE model (Ward, 1986) which allows to integrate these different design steps. This model is the ACSY-R model (French equivalent of Distributed SYstem Command Design). The ACSY-R model is based on the cooperation of various models. These models allow to describe the software command system analysis and the architecture analysis. They permit the merging of control part and architecture part, taking into account the different temporal and physical constraints. At last, the validation step is covered by discrete events simulation. 2. SOITWARE COMMAND SYSTEM SPECIFICA TION The software control specification needs to describe three aspects which are commonly admitted (Yourdon, 1989). These aspects are the functionnal specification, the dynamic specification and the data processing specification (See figure 1) . 117 Functionnalaspect , , ,. _. I Dynamic Data processing aspect aspect Figure I : The control part design aspects 2.1. Top-down approach andfunctionnal specification The control modeling in ACSY-R is always performed according to a toJHlown approach inspired by models such as SADT (Structured Analysis Design Tecoique) (Marca, 1988), SA-RT (Structured Analysis Real Time) (Hatley, 1987) or ESML and ESML+ (Extended System Modeling Language) (Broyn, 1988). The top of the hierarchy is the Context Diagram in which the control can be situated in its environment (sensors, actuators, etc.). The box containing the Context Diagram is splitted up into a first Flows Diagram in which more simple functions appear. This second level of description is then split up into other Flows Diagrams. Boxes are splitted up agrun and again until simple boxes (called 'primitive boxes') are obtained. These boxes contain the data processing or the dynamic behaviour description. All the communications between the different boxes, called 'flows', are gathered and defined in a centralized database: the dictionnary. This database