彈性製造單元現場排程模組之構建

Abstract

彈性製造單元(Flexible Manufacturing Cell;FMC)的規劃與管理，可分 為生產規劃(Production Planning)及現場排程(Shop Floor Scheduling) 兩層次。現場排程承接生產規劃之訂單生產資料輸出，針對製造現場的狀 況，進行物流決策之控制。如何將上層的規劃真正落實到下層的生產活動 ，是一個相當重要的課題；這需要考慮現場生產時的設備限制，對現場資 源做最佳的排程和配置。本論文的主要目的即是針對彈性製造單元構建一 套現場排程模組，使排程結果有助於現場實際生產活動的控制，達成生產 目標。彈性製造單元之生產排程考慮夾具夾持特徵、配置托板/夾具、及 製成中換托板/夾具等性質。本文針對現場機器、AGV、裝卸站，托板/夾 具等資源，由各資源相互配合的觀點，擬定工件、機器、AGV的排程規劃 ，及在製品之途程選擇策略。排程之擬定是以啟發式法則兼顧即時式排程 特徵的作法，來掌握系統短期生產動向。彈性製造單元的現場排程，常有 存貨的限制。本現場排程模組，以投料控制因子(ICF)設定值，控制現場 最大容許存量。而此設定值的大小，影響批次完成時間、工件延遲時間、 及工件流動時間等生產績效，因此本論文亦探討了最大存貨量的設定對系 統績效之影響。 The planning and control of the flexible manufacturing cell( FMC) consists of two levels; production planning and shop floor scheduling. The production planning level plans the production orders for a given period. The shop floor scheduling level then arranges the corresponding material movements of these product orders, with consideration of the shop floor status. How to execute the production activity to accomplish the upper planning results is an important problem. It needs to consider the resources' constraints for deciding the best schedule and resource allocations. This thesis therefore aims at constructing a shop floor scheduling module for the FMC to accomplish the production goals. The production scheduling of the FMC needs to consider some operation characteristics such as the features of fixtures clamping, the pallet/fixture matching, the pallet/fixture changing in manufacturing process, etc. This shop floor scheduling module thus develops the scheduling rules for various resources (machines, AGV, and loading/unloading stations), and the routing selection rules for parts. These heuristic rules are developed from system integration viewpoint and from real-time scheduling prospective. It thus can grasps the short-term production trend of the FMC. The shop floor of an FMC usually has the inventory limits. Therefore, the scheduling module establishes the input control factor (ICF) to control the maximum inventory in the shop floor. This ICF value influences the batch completion time, the part flow time. This thesis thus also discusses the influence of the ICF value on the system performance.