Research Papers

Aggressive Spiral Toolpaths for Pocket Machining Based on Medial Axis Transformation

[+] Author and Article Information
Nuodi Huang

School of Power and Mechanical Engineering,
Wuhan University,
Wuhan 430072, China
e-mail: huangnuodi@126.com

Roby Lynn

George W. Woodruff School
of Mechanical Engineering,
Georgia Institute of Technology,
Atlanta, GA 30332
e-mail: roby.lynn@gatech.edu

Thomas Kurfess

George W. Woodruff School
of Mechanical Engineering,
Georgia Institute of Technology,
Atlanta, GA 30332
e-mail: kurfess@gatech.edu

1Corresponding author.

Manuscript received July 21, 2016; final manuscript received January 3, 2017; published online January 30, 2017. Assoc. Editor: Xiaoping Qian.

J. Manuf. Sci. Eng 139(5), 051011 (Jan 30, 2017) (8 pages) Paper No: MANU-16-1400; doi: 10.1115/1.4035720 History: Received July 21, 2016; Revised January 03, 2017

High-speed machine tools typically provide high spindle speeds and feedrates to achieve an effective material removal rate (MRR). However, it is not possible to realize the full extent of their high-speed capabilities due to the sharp corners of toolpaths which are introduced by conventional machining strategies, such as contour- and direction-parallel toolpaths. To address this limitation, spiral toolpaths that can reduce the magnitude of sudden direction changes have been developed in previous researches. Nevertheless, for some pockets, the average radial cutting width is significantly decreased while the total length of the toolpath is significantly increased as compared to contour- and direction-parallel toolpath. In this situation, spiral toolpath may take more machining time. To overcome these drawbacks, an aggressive spiral toolpath generation method based on the medial axis (MA) transformation is proposed in machining pocket without islands inside, which refers to no additional material inside the counter. The salient feature of this work is that it integrates the advantages of both conventional contour-parallel machining strategy and the existing spiral toolpath machining strategy. The cutting width at each MA point is determined based on the diameter of the locally inscribed circle (LIC) of the MA point and the topological structure of MA. A distance-constrained contour determination algorithm is utilized to calculate the toolpath for each pass. Finally, a circular arc transition strategy is used to transform all the isolated passes into a spiral toolpath. Experiments are conducted to show the effectiveness of the proposed method.

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Pateloup, V. , Duc, E. , and Ray, P. , 2004, “ Corner Optimization for Pocket Machining,” Int. J. Mach. Tools Manuf., 44(12), pp. 1343–1353. [CrossRef]
Bi, Q. Z. , Shi, J. , Wang, Y. H. , Zhu, L. M. , and Ding, H. , 2015, “ Analytical Curvature-Continuous Dual-Bézier Corner Transition for Five-Axis Linear Tool Path,” Int. J. Mach. Tools Manuf., 91, pp. 96–108. [CrossRef]
Lin, Z. , Fu, J. , Shen, H. , Gan, W. , and Yue, S. , 2015, “ Tool Path Generation for Multi-Axis Freeform Surface Finishing With the LKH TSP Solver,” Comput.-Aided Des., 69, pp. 51–61. [CrossRef]
Fu, Q. , 2010, “ A New Geometric-and-Physics Model of Milling and an Effective Approach to Medial Axis Transforms of Free-Form Pockets for High Performance Machining,” Ph.D. thesis, Concordia University, Montréal, QC.
Pamali, A. P. , 2004, “ Using Clothoidal Spirals to Generate Smooth Tool Paths for High Speed Machining,” Master thesis, North Carolina State University, Raleigh, NC.
Pavanaskar, S. , Pande, S. , Kwon, Y. , Hu, Z. , Sheffer, A. , and McMains, S. , 2015, “ Energy-Efficient Vector Field Based Toolpaths for CNC Pocket Machining,” J. Manuf. Process., 20(Part 1), pp. 314–320. [CrossRef]
Bahloul, E. , Brioua, M. , and Rebiai, C. , 2015, “ An Efficient Contour Parallel Toolpath Generation for Arbitrary Pocket Shape Without Uncut Regions,” Int. J. Precis. Eng. Manuf., 16(6), pp. 1157–1169. [CrossRef]
Zhao, Z. Y. , Wang, C. Y. , Zhou, H. M. , and Qin, Z. , 2007, “ Pocketing Toolpath Optimization for Sharp Corners,” J. Mater. Process. Technol., 192–193, pp. 175–180. [CrossRef]
Bieterman, M. B. , and Sandstrom, D. R. , 2002, “ A Curvilinear Tool-Path Method for Pocket Machining,” ASME Paper No. IMECE2002-33611.
Ding, D. , Pan, Z. S. , Cuiuri, D. , and Li, H. , 2014, “ A Tool-Path Generation Strategy for Wire and Arc Additive Manufacturing,” Int. J. Adv. Manuf. Technol., 73(1–4), pp. 173–183. [CrossRef]
Sun, Y. W. , Guo, D. M. , and Jia, Z. Y. , 2006, “ Spiral Cutting Operation Strategy for Machining of Sculptured Surfaces by Conformal Map Approach,” J. Mater. Process. Technol., 180(1), pp. 74–82. [CrossRef]
Xu, J. , Sun, Y. , and Zhang, X. , 2013, “ A Mapping-Based Spiral Cutting Strategy for Pocket Machining,” Int. J. Adv. Manuf. Technol., 67(9–12), pp. 2489–2500. [CrossRef]
Gong, H. , Wang, Y. , Song, L. , and Fang, F. Z. , 2015, “ Spiral Tool Path Generation for Diamond Turning Optical Freeform Surfaces of Quasi-Revolution,” Comput.-Aided Des., 59, pp. 15–22. [CrossRef]
Chuang, J. J. , and Yang, D. C. H. , 2004, “ A Laplace-Based Spiral Contouring Method for General Pocket Machining,” ASME Paper No. IMECE2004-60138.
Ren, F. , Sun, Y. , and Guo, D. , 2009, “ Combined Reparameterization-Based Spiral Toolpath Generation for Five-Axis Sculptured Surface Machining,” Int. J. Adv. Manuf. Technol., 40(7–8), pp. 760–768. [CrossRef]
Banerjee, A. , Feng, H. Y. , and Bordatchev, E. V. , 2012, “ Process Planning for Floor Machining of 2½D Pockets Based on a Morphed Spiral Toolpath Pattern,” Comput. Ind. Eng., 63(4), pp. 971–979. [CrossRef]
Romero-Carrillo, P. , Torres-Jimenez, E. , Dorado, R. , and Díaz-Garrido, F. , 2015, “ Analytic Construction and Analysis of Spiral Pocketing Via Linear Morphing,” Comput.-Aided Des., 69, pp. 1–10. [CrossRef]
Abrahamsen, M. , 2015, “ Spiral Toolpaths for High-Speed Machining of 2D Pockets With or Without Islands,” ASME Paper No. DETC2015-46255.
Held, M. , and Spielberger, C. , 2009, “ A Smooth Spiral Toolpath for High Speed Machining of 2D Pockets,” Comput.-Aided Des., 41(7), pp. 539–550. [CrossRef]
Yao, Z. , and Joneja, A. , 2007, “ Path Generation for High Speed Machining Using Spiral Curves,” Comput.-Aided Des. Appl., 4(1–4), pp. 191–198.
Yao, Z. , 2006, “ A Novel Cutter Path Planning Approach to High Speed Machining,” Comput.-Aided Des. Appl., 3(1–4), pp. 241–248.
Makhe, A. , and Frank, M. C. , 2010, “ Polygon Subdivision for Pocket Machining Process Planning,” Comput. Ind. Eng., 58(4), pp. 709–716. [CrossRef]
Held, M. , and Spielberger, C. , 2014, “ Improved Spiral High-Speed Machining of Multiply-Connected Pockets,” Comput.-Aided Des. Appl., 11(3), pp. 346–357.
Chen, Z. C. , and Zhang, H. , 2009, “ Optimal Cutter Size Determination for 2½-Axis Finish Machining of NURBS Profile Parts,” Int. J. Prod. Res., 47(22), pp. 6279–6293. [CrossRef]
O'Rourke, J. , 1998, Computational Geometry in C, 2nd ed., Cambridge University Press, Cambridge, UK.


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Fig. 5

Architecture of proposed approach

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Fig. 4

Toolpath generation process: (a) isolated passes and (b) spiral toolpath

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Fig. 6

Update pass number for MA points: (a) before update and (b) after update

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Fig. 7

Algorithm to determine pass number

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Fig. 9

Tangent points between local circles and envelope curve

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Fig. 8

Toolpath optimization at tip area

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Fig. 3

Structure of MA circulation loop

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Fig. 2

Basic elements of the MA of a pocket

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Fig. 1

Pocket machining toolpaths: (a) zigzag path, (b) one-way path, (c) contour parallel path, and (d) spiral path

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Fig. 17

Combination strategy of adjacent passes: (a) cam package and (b) proposed method

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Fig. 10

Toolpath for each pass

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Fig. 11

Contour determination with distance constraint

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Fig. 12

Smoothed toolpath for each pass

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Fig. 13

Connection strategy between adjacent passes

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Fig. 16

Demonstrations of developed method in case 3

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Fig. 14

Generated spiral toolpath by proposed method

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Fig. 15

Spiral toolpaths generated by proposed and existing methods




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