UML Modelling in Rigorous Design Methodology for Discrete Controllers

Abstract—The paper presents an application of UML technol-ogy in a discrete system development process. In the process at theanalysis stage UML diagrams are fundamental tool. The outcomeof this stage is a basis for formal models exploited at the designstage, where the design is symbolically verified and treated as arule-based system. Two formal models of good graphical appealare proposed: Petri nets and state machine diagrams. Both areheavily using Boolean expressions what makes that design caneasily be implemented in modern programmable structures.Keywords—UML modelling, binary controller, decomposition,digital synthesis, formal analysis, verification. I. I NTRODUCTION D ISCRETE system is a system with countable number ofstates. One of such systems is a discrete control system,where the controller generates signals to the controlled objectand the controlled object responds to the controller (Fig. 1) [1].Moreover, the controller receives signals from an operator andgenerates signals to the operator. For an engineer the designof the system mainly involves the control unit design and thecontrolled object and its behaviour are requirements given bya client. If the signals are of binary value the controller is abinary controller and can be produced as a digital circuit (eg.FPGA or CPLD) [2], [3].