無人搬運車之整合性指派法則的研究

Abstract

一般而言物，料在生產過程中，尤其是批量加工之零工型工廠中，有 效加工時間所佔的比例低，而花費在運送、等待的時間則相對地佔有相當 高的比例，因此物料搬運系統能否有效率的執行對於系統之績效有很大的 影響。基於彈性、安裝容易與可移動性等優點，無人搬運車可適用於多種 製造環境，便逐漸成為廣泛採用的物料搬運工具之一。 目前無人搬運 車之控制，大都是經由派車法則所設定的優先次序來決定無人搬運車執行 載運任務的對象。雖然近十餘年來已有不少的派車法則發展出來，但是較 少研究討論彈性調整且充分考慮生產時的實際情況的指派法則。因此本研 究希望結合傳統推的策略與JIT拉的策略，同時加上獎勵項目的方式，發 展出一個充分考慮生產系統中的各種因素之整合性指派法則。並藉此比較 簡單的車輛指派法則與考慮多因素之指派法則間對系統績效的影響。 Then transportation time and queue time in general job shop manufacturing system are relatively much higher in comparing with the effective processing time. Therefore, whether the material handling system can be efficiently and effectively executed become one of the most crucial factors influencing the system performance. Because the automated guided vehicle (AGV) system has merits of the flexibility, ease of installation, and mobility, it has been widely accepted and applied in many manufacturing environments. In order to make an AGV deliver right parts to right machines at right time, AGV's dispatching rules that determine its dispatching priorities need to be planed a priori. Althought many AGV's dispatching rules have been developed in the past two decades, each of them has claimed itself suitable for certain performance critera. This research present a hybrid AGV dispatching rule which combines the traditional "push" strategy, the "pull" strategy originating from jist-in-time concept, and a "bonus" strategy. An experiment is designed to extensively compare the system performance under the proposed hybrid dispatching rule with those under other well-recognized ones (STT/D, MOQS, and MIX). When a system is relativelt stable, it is demonstrated that simple rules such as STT/D and MOQS perform as good as complicated rules do.