Performance modeling of reconfigurable manufacturing system for different dispatching strategies under exception

A Reconfigurable Manufacturing System (RMS) is having potential for quick adjustment in its production capacity and functionality. These RMSs are considered to be one of the technologies enabling shorter lead times, more product variants, fluctuating volumes of products, shorter product life cycles and lower cost. This paper presents the performance modeling of a hybrid system comprising of dedicated and reconfigurable machine tools simultaneously. The modeling focuses on handling of exceptional situations. One such handling situation arises when there is a breakdown of any resource like machine within the system. The dedicated machines are subjected to random failures and once there is the failure, the jobs are transferred to the reconfigurable machines after suitable reconfiguration to carry out the sequential operation required on the job. Two different production scenarios, first, operation of the system over some predetermined period of time and, secondly, operation of the system for a fixed quantity of products were modeled using ARENA^® discrete event simulation software. Three different dispatching strategies for reactive scheduling of parts based on total average waiting time in queue, total downtime of the failed machine and capacity of the buffer in between the machines were analyzed. The performance of the system was analyzed in terms of productivity, congestion and make-span time. Finally, the results were analyzed and were discussed in the light of previous researches carried out on the topic.