簡易檢索 / 詳目顯示

研究生: 徐鵬
Xu, Peng
論文名稱: 基於類神經網路切削力預測模型的五軸銑削製程優化之研究
Studies on Process Optimization Based on the Cutting Force Prediction Model of an Artificial Neural Network for Five-axis Milling
指導教授: 李榮顯
Lee, Rong-Shean
學位類別: 碩士
Master
系所名稱: 工學院 - 機械工程學系
Department of Mechanical Engineering
論文出版年: 2015
畢業學年度: 103
語文別: 英文
論文頁數: 72
中文關鍵詞: 製程優化切削力預測五軸加工類神經網路
外文關鍵詞: process optimization, cutting force prediction, five-axis milling, artificial neural network
相關次數: 點閱:91下載:6
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報
  • 如今五軸加工系統和CNC工具機已經為高精度加工製造帶來了很大的便利。然而,為了在實際中避免刀具的損壞和斷裂,人們在設計加工策略比較保守,使得加工參數往往較低。這一行為則導致了加工時間的大量增加,影響了生產的效率。所以如何提高生產效率為目前五軸加工的重要議題,尤其是對於加工有複雜曲面的工件而言。
    隨著虛擬模擬技術的發展,在加工之前直接優化加工參數被認為是提高效率行之有效的手段。基於這一點,本文提出一種新的銑削製程優化方法以統籌銑削約束條件並調整加工參數,從而最大化五軸銑削的加工效率。在眾多約束條件中,切削力約束最為重要。所以,本文首先從切削力模型中分析出必要的切削力成分,經由模擬採集大量銑削數據來訓練類神經網路以達到預測銑削力的目的。然後,本文將包括運動狀況和切削力在內的所有約束條件建立為銑削約束條件模型,以計算出每段切削區間的最優化主軸轉速和進給率。在得到每一加工區間的最佳結果後,又設計出一整套製程優化算法來評估和整合製程中優化參數。至此,所有的優化過程都在虛擬環境中得以實施。而最終優化後的加工數據可以直接用來修改刀具位置檔(CL)。此外,本文通過幾個加工案例來驗證本文方法的優化性能。驗證結果證實了該方法的有效性和可靠性。

    The evolution of the five-axis machining systems and Computer Numerical Control (CNC) machine tools has provided considerable advantages for high-precision manufacturing. However, due to a conservative machining strategy,parameter value shave usually been preset as constants to avoid tool damage or breakage. Unfortunately, this practice leads to a great expense of machining time. So improving production efficiency is an important issue for machining applications such as five-axis milling, especially when machining complex surface parts.

    With the development of virtual simulation technology, optimizing machining parameters before machining is now recognized as a feasible method to improve efficiency. Based on this consideration, this thesis proposes a novel milling process optimization method to regulate milling constraints and adjust parameters so as to maximize the five-axis milling efficiency. As cutting force is the primary constraint, the cutting-force model is first analyzed to identify the necessary force components. The employed artificial neural network (ANN) is trained with collected milling data to predict milling force. Then,a model with all constraints, including drive conditions and force,is established to compute the optimal spindle speed and feed rate in each cutting engagement interval. With the optimized results of each milling interval, a series of process optimization algorithms are proposed to evaluate and integrate the optimal parameters in the process. All these processes are carried out in a virtual machining environment. Finally, the new milling data could be used to directly modify the cutter location (CL)file. In Addition, several case examples have been provided to verify the optimization performance of this method, which was found to be effective and reliable.

    Table of Contents 摘要 I Abstract II Acknowledgement III Table of Contents IV List of Tables VI List of Figures VII Nomenclature IX Chapter 1 Introduction 1 1.1 Background 1 1.2 Literature review 2 1.2.1. Cutting Force Prediction 3 1.2.2. Cutting Process Optimization 4 1.3 Research purpose 7 1.4 Outline of the study 7 Chapter 2 Establishment of Cutting Force Model 9 2.1 Overview 9 2.2 Five-axis milling force model 10 2.3 Modeling force with ANN 11 2.3.1. RBFN Introduction 11 2.3.2. Data preparation 14 2.3.3. Data preprocessing 20 2.3.4. Network training results and analysis 21 Chapter 3 Cutting process optimization model 27 3.1 Optimization overview 27 3.2 Optimization Constraints 29 3.2.1. Cutting Force Constraint 29 3.2.2. Cutter Stability Constraint 30 3.2.3. Drive Condition Constraint 32 3.3 Optimization Scheme 34 3.3.1. Optimization Model 34 3.3.2. Preparation for CL file’s modification 35 3.3.3. Spindle speed optimization 36 3.3.4. Feed rate adjustment strategy 42 Chapter 4 Results and discussion 47 4.1 Cutting force prediction 47 4.2 Milling process optimization 51 4.2.1. Case 1: rough milling process optimization 52 4.2.2. Case 2: semi-finish milling process optimization 56 4.3 Comparison between RBFN-based method and MRR-based method 62 Chapter 5 Conclusion and suggestions 65 5.1 Conclusion 65 5.2 Suggestions 67 References 69

    Altinta, Y., “Analytical prediction of chatter stability in milling—part II: application of the general formulation to common milling systems,” Journal of Dynamic Systems, Measurement, and Control, Vol. 120, No. 1, pp. 31-36, 1998.
    Altintaş, Y., and Budak, E., “Analytical prediction of stability lobes in milling,” CIRP Annals-Manufacturing Technology, Vol. 44, No. 1, pp. 357-362, 1995.
    Altintaş, Y., and Lee, P., “A general mechanics and dynamics model for helical end mills,” CIRP Annals-Manufacturing Technology, Vol. 45, No. 1, pp. 59-64, 1996.
    Aykut, Ş., Gölcü, M., Semiz, S., and Ergür, H. S., “Modeling of cutting forces as function of cutting parameters for face milling of satellite 6 using an artificial neural network,” Journal of Materials Processing Technology, Vol. 190, No. 1, pp. 199-203, 2007.
    Briceno, J. F., El-Mounayri, H., and Mukhopadhyay, S., “Selecting an artificial neural network for efficient modeling and accurate simulation of the milling process,” International Journal of Machine Tools and Manufacture, Vol. 42, No. 6, pp. 663-674, 2002.
    Budak, E., Altintas, Y., andArmarego, E. J. A.,“Prediction of milling force coefficients from orthogonal cutting data,” Journal of Manufacturing Science and Engineering, Vol. 118, No. 2, pp. 216-224, 1996.
    Cus, F., Milfelner, M., and Balic, J., “An intelligent system for monitoring and optimization of ball-end milling process,” Journal of Materials Processing Technology, Vol. 175, No. 1, pp. 90-97, 2006.
    Demuth, H., and Beale, M., “Neural network toolbox user’s guide,” The MathWorksInc, USA, 2000.
    Erkorkmaz, K., Layegh, S. E., Lazoglu, I., and Erdim, H., “Feedrate optimization for freeform milling considering constraints from the feed drive system and process mechanics,” CIRP Annals-Manufacturing Technology, Vol. 62, No. 1, pp. 395-398, 2013.
    Ezugwu, E. O., Fadare, D. A., Bonney, J., Da Silva, R. B., and Sales, W. F., “Modelling the correlation between cutting and process parameters in high-speed machining of Inconel 718 alloy using an artificial neural network,” International Journal of Machine Tools and Manufacture, Vol. 45, No. 12, pp. 1375-1385, 2005.
    Jin, Y. A., He, Y., and Fu, J. Z., “A look-ahead and adaptive speed control algorithm for parametric interpolation,” The International Journal of Advanced Manufacturing Technology, Vol. 69, No. 9-12, pp. 2613-2620, 2013.
    Li, Z. Z., Zhang, Z. H., and Zheng, L., “Feedrate optimization for variant milling process based on cutting force prediction,” The International Journal of Advanced Manufacturing Technology, Vol. 24, No. 7-8, pp. 541-552, 2004.
    Lim, E. M., and Menq, C. H., “Integrated planning for precision machining of complex surfaces. Part 1: cutting-path and feedrate optimization,” International Journal of Machine Tools and Manufacture, Vol. 37, No. 1, pp. 61-75, 1997.
    Milfelner, M., Cus, F., and Balic, J., “An overview of data acquisition system for cutting force measuring and optimization in milling,” Journal of Materials Processing Technology, Vol. 164, pp. 1281-1288, 2005.
    Quintana, G., and Ciurana, J., “Chatter in machining processes: A review,” International Journal of Machine Tools and Manufacture, Vol. 51, No. 5, pp. 363-376, 2011.
    Shunmugam, M. S., Reddy, S. B., and Narendran, T. T., “Selection of optimal conditions in multi-pass face-milling using a genetic algorithm,” International Journal of Machine Tools and Manufacture, Vol. 40, No. 3, pp. 401-414, 2000.
    Sun, Y., Bao, Y., Kang, K., and Guo, D., “An adaptive feedrate scheduling method of dual NURBS curve interpolator for precision five-axis CNC machining,” The International Journal of Advanced Manufacturing Technology, Vol. 68, No. 9-12, pp. 1977-1987, 2013.
    Sun, Y., Zhao, Y., Bao, Y., and Guo, D., “A novel adaptive-feedrate interpolation method for NURBS tool path with drive constraints,” International Journal of Machine Tools and Manufacture, Vol. 77, pp. 74-81, 2014.
    Tandon, V., and El-Mounayri, H., “A novel artificial neural networks force model for end milling,” The International Journal of Advanced Manufacturing Technology, Vol. 18, No. 10, pp. 693-700, 2001.
    Tandon, V., El-Mounayri, H., and Kishawy, H., “NC end milling optimization using evolutionary computation,” International Journal of Machine Tools and Manufacture, Vol. 42, No. 5, pp. 595-605, 2002.
    Tikhon, M., Ko, T. J., Lee, S. H., and Kim, H. S., “NURBS interpolator for constant material removal rate in open NC machine tools,” International Journal of Machine Tools and Manufacture, Vol. 44, No. 2, pp. 237-245, 2004.
    Wang, Y., Wang, T., Yu, Z., Zhang, Y., Wang, Y., and Liu, H.,“Chatter Prediction for Variable Pitch and Variable Helix Milling,” Shock and Vibration,2015.
    Wang, Z. G., Wong, Y. S., and Rahman, M., “Optimisation of multi-pass milling using genetic algorithm and genetic simulated annealing,” The International Journal of Advanced Manufacturing Technology, Vol. 24, No. 9-10, pp. 727-732, 2004.
    Wu, C. H., “Application of Cutting Geometry to Evaluation of Milling Force for Five-Axis Virtual Machining,” M. S. Thesis, Department of Mechanical Engineering, National Cheng Kung University, 2011.
    Yazar, Z., Koch, K. F., Merrick, T., and Altan, T., “Feed rate optimization based on cutting force calculations in 3-axis milling of dies and molds with sculptured surfaces,” International Journal of Machine Tools and Manufacture, Vol. 34, No. 3, pp. 365-377, 1994.
    Zhang, X., Yu, T., and Wang, W., “Modeling, simulation, and optimization of five-axis milling processes,” The International Journal of Advanced Manufacturing Technology, Vol. 74, No. 9-12, pp. 1611-1624, 2014.
    Zhou, J., Sun, Y., and Guo, D., “Adaptive feedrate interpolation with multiconstraints for five-axis parametric toolpath,” The International Journal of Advanced Manufacturing Technology, Vol. 71, No. 9-12, pp. 1873-1882, 2014.
    Zou, X. Y., “BP supervised training of radial basis function (RBF) network,” Oct. 28, 2013. http://blog.csdn.net/zouxy09/article/details/13297881
    Zuperl, U., and Cus, F., “Tool cutting force modeling in ball-end milling using multilevel perceptron,” Journal of Materials Processing Technology, Vol. 153, pp. 268-275, 2004.
    Zuperl, U., Cus, F., Mursec, B., and Ploj, T., “A generalized neural network model of ball-end milling force system,” Journal of Materials Processing Technology, Vol. 175, No. 1, pp. 98-108, 2006.

    下載圖示 校內:2017-08-01公開
    校外:2017-08-01公開
    QR CODE