Christine Gertosio

A distributed decision support system for operational units application to a manufacturing unit

Nowadays, a lot of machines are able to execute complex processes in the manufacturing units. Other machines can execute complex treatments for medical units. The main constraint for using these machines is the good scheduling of the tasks of preparation and the preventive maintenance tasks, which are required. These tasks are manual or semi-automated tasks but they need operators. When several machines are grouped in a unit, it is important to organize the environmental tasks for getting the effectiveness of the entire unit. In order to increase the effectiveness of this kind if units, we studied a decision support system (DSS) for the units operators. The objective of this system is to communicate with each operator category in order to give him the list of next executable actions. This DSS does not control the production facilities; it does not define very elaborate strategies for management: it is based on decisions taken by the operators. The paper discusses about the architectures of the DSS. We identified a hybrid architecture with generic subsystems to manage different types of resources. The DSS has a distributed architecture which can use a distributed environment (object based on MOM middleware). The objective of the distributed environment is to simplify the applications and to insure the independence of the DSS from the communication network. The case study is taken in the domain of the manufacturing: the diesel engines for trucks are manufactured on three assembly lines and the studied unit performs the test of the engines coming from the lines. The case study illustrates the use of the generic part of DSS (subsystems) and that of the message oriented middleware (MOM) system for insuring the communication between the distributed part of the DSS.

Modeling of the test workshop controller

The preliminary specification of the computerized controller for a workshop is related here. The aim of the controller is to help the operators to take in real time the best decision according to the sequencing of the products. The workshop is a real one consisting of 22 workstations, skilled operators, forklift trucks and a storage area. This paper develops the modeling using the object-oriented formalism UML. This study has permitted to identify new object classes of and to define an alternative solution for the management of the storage area.