A Study on the Tool Sharing Policy in FMS with Tool Center

Abstract

In this paper we examine the issue of tool management in a Flexible Manufacturing System (FMS). A tool center storing all tools for jobs is introduced and all tools can be shared by the machining centers through tool change between the machining centers and the tool center. Two tool-change methods, “Augmented Magazine Method (AMM)” and “Magazine Carrier Method (MCM)”, are proposed and evaluated using the methods for the allocation of tools and jobs proposed in this study. A job in this study is defined as a sequence of processing operations and is thus processed by a single machining center. We propose a two-stage method to integrate tool planning and the allocation of tools and jobs. The method in the second stage for the allocation of tools and jobs is proposed on the basis of an auction method including a dispatching rule. For the tool planning with AMM at the first stage, we propose a greedy search method to decide the total number of tools. By simulation, we investigate the characteristics and effectiveness of the proposed two-stage method and the tool-change methods together with the effectiveness of several dispatching rules.