基於孔特徵辨識之孔加工工序規劃

Abstract

在加工零件過程中使用CAM軟體以產生加工路徑，可提高產品生產效率，但還是需要具備加工經驗人員操作軟體並且以人工方式選取加工區域與加工條件。 本研究針對工件上之鑽孔特徵，建立出孔特徵辨識演算法、對應的孔加工規劃流程以及優化每道次的孔加工路徑。在孔特徵辨識方面，辨識出STEP圖檔的孔加工特徵，當孔特徵互相干涉時，也能正確辨識。在獲得孔特徵的幾何尺寸之後，依照實際加工機台所提供的加工能力、所使用的加工參數來新增預鑽削工法，並且考量較少的加工道次與換刀次數條件下安排預鑽削。而每道次之刀具選用是從刀具庫中選出適合之鑽頭作加工，安排出孔加工工序。在計算每道工序之加工路徑時，本研究藉由貪婪演算法與兩元素優化法優化加工孔之順序，可減少48%之空行程，提升加工效率。 本研究藉由孔特徵辨識技術可減少人為判斷加工區域錯誤性與增加產生加工路徑的效率，加上藉由鑽孔工序安排，可減少換刀次數和加工時間，大幅提升加工規劃效率。

The mechanical manufacturer can improve production efficiency and product quality by using CAM software. However, it is necessary to have the practical experience to operate the software and manually select the processing area based on the workpiece geometry. In this study, a drilling feature recognition algorithm is developed to identify the drilling features from STEP files of CAD. When the detailed geometric dimensions of the hole feature are obtained, drilling procedures and processing paths can be planned. In this study, drilling processes are planned according to the machine tool, tool library and hole feature. The drilling path is automatically generated by considering the actual processing and the algorithm of reducing the toolpath. In calculating the toolpath of each process, the greedy algorithm and two- optimization algorithm are used to optimize the order of the holes, which can reduce the empty travel by 48% and improve the processing efficiency. The results show that the mistakes of manual judgment of processing area can be reduced by hole feature recognition, and the numbers of tool changes and processing time can be reduced by drilling process planning, which greatly improves the processing efficiency.