Basic study on production scheduling method for highly-distributed manufacturing systems

Abstract

Recent development of computer network technologies is realizing highly-distributed manufacturing systems from the hardware point of view, where each facility is computerized and manages itself autonomously by communicating with other facilities. For this new type of manufacturing systems, a new discrete event simulation paradigm has been discussed, in which sorting of events is performed by exchanging messages about their occurrence times among the facilities. To make this paradigm beneficial enough, it is desirable that re-scheduling process performed after the simulation is carried out in a similar paradigm. For this reason, a highly-distributed scheduling method was proposed, where priority of each facility for job assignment is dynamically updated with indirect decision making and information control performed by a communication protocol. However, this method was developed only for a very simple scenario, and should be enhanced so that it can be utilized in real manufacturing. This paper presents an improved method which can handle the more complicated scenario where materials are transported to a production area one-by-one at non-constant time periods and some of them cannot be assigned to any machine at its arrival time.

Keywords

• production scheduling
• dispatching rules
• distributed manufacturing systems
• agile manufacturing