A METHOD OF FLEXIBLE JOB-SHOP SCHEDULING FOR HIGHLY-DISTRIBUTED MANUFACTURING SYSTEMS

Recent advances in computer and network technologies is achieving highly-distributed manufacturing systems (HDMSs) from the hardware point of view, where each facilities is computerized and manages itself autonomously by communicating with other facilities. Considering this hardware environment, a distributed method for flexible job-shop scheduling (FJS) was proposed, where machine selection based on a dispatching rule and driving of occurrence of events on facilities are performed by communication among facilities. In this method, only the simplest dispatching rules for machine selection and job selection were considered, and the obtained schedule may not be acceptable enough. It is desirable to enhance this method so that other rules can be utilized and various schedules are obtained. This paper deals with some other rules (LPT, LWKR, MWKR, EDD, NINQ) and provides a distributed FJS method for HDMSs based on those rules. Feasibility of the proposed method was proven by an example.