The thesis describes a method for the rapid, incremental design and implementation of manufacturing systems utilising a combined object-oriented and structured Petri net formalism. The background to the problems facing manufacturing organisations wishing to implement computers into manufacturing systems is presented along with a discussion of how software engineering techniques can be applied to overcome them. Modularity and object-orientation are proposed as a way of enhancing the development of manufacturing systems. A review of current techniques for modelling manufacturing systems is presented which outlines the benefits and drawbacks of a number of methods. A three-level control architecture is developed which distributes complexity amongst the low levels of the system. The control structure is combined with a behavioural constraint object to ensure that maximum reuse can be gained from objects in the system. A formalism for integrating Petri nets into the UML is outlined, entitled Functionally Encapsulated Modules. These modules provide full object-oriented capabilities coupled with the functional modelling power of Petri nets. State space explosion is reduced as Petri nets are used only for modelling the functionality of objects. However, the modules also retain the abilities of simulation tool and mathematical proof of the original Petri net. The methodology and modelling tools are evaluated by applying them to a discrete event manufacturing system.Conclusions are then drawn on the various aspects of the work and details of further research possibilities are described.
|Date of Award||May 2009|