Smooth non-uniform rational B-spline (NURBS) machining with kinematic limit for short linear segments

Set of methods based on non-uniform rational B-spline (NURBS) are proposed in this article, which are adopted to improve the smoothness during short linear numerical control (NC) codes machining. The smoothness refers to two aspects: the contour fairness of CL trajectory and the machining stability of the machine tool. To obtain contour fairness, the optimised knots combination strategy (OKCS) is proposed in least square NURBS fitting from short linear segments, which generates NURBS curve for the next interpolating process. Sequentially, an axis-based look-ahead NURBS interpolator (ALANI) is designed for NURBS interpolation in order to improve the machining stability according to the kinematic limit. Both OKCS and ALANI are simulated and compared with congener algorithms, respectively. Furthermore, algorithms are implemented on digital signal processor (DSP) platform, and actual machining examples are presented at last.

[1]  Jiing-Yih Lai,et al.  CNC codes conversion from linear and circular paths to NURBS curves , 2008 .

[2]  Muhammad Sarfraz,et al.  Capturing outline of fonts using genetic algorithm and splines , 2001, Proceedings Fifth International Conference on Information Visualisation.

[3]  Hyungjun Park,et al.  A method for approximate NURBS curve compatibility based on multiple curve refitting , 2000, Comput. Aided Des..

[4]  Hu Chen,et al.  Implementation of a CNC NURBS curve interpolator based on control of speed and precision , 2009 .

[5]  L. Schumaker,et al.  Curves and surfaces in geometric design , 1994 .

[6]  Jiing-Yih Lai,et al.  Reverse engineering of composite sculptured surfaces , 1996 .

[7]  Dirk Zeckzer,et al.  Approximation of NURBS curves and surfaces using adaptive equidistant parameterizations , 2005 .

[8]  Syh-Shiuh Yeh,et al.  The speed-controlled interpolator for machining parametric curves , 1999, Comput. Aided Des..

[9]  J. Kruth,et al.  NURBS curve and surface fitting for reverse engineering , 1998 .

[10]  Ahmet Arslan,et al.  Automatic knot adjustment using an artificial immune system for B-spline curve approximation , 2009, Inf. Sci..

[11]  Toshinobu Harada,et al.  Automatic knot placement by a genetic algorithm for data fitting with a spline , 1999, Proceedings Shape Modeling International '99. International Conference on Shape Modeling and Applications.

[12]  Syh-Shiuh Yeh,et al.  Implementation of online NURBS curve fitting process on CNC machines , 2009 .

[13]  Josef Hoschek,et al.  Approximate conversion and data compression on integral and rational B-spline surfaces , 1994 .

[14]  Siti Mariyam Hj. Shamsuddin,et al.  Particle Swarm Optimization for NURBS Curve Fitting , 2009, 2009 Sixth International Conference on Computer Graphics, Imaging and Visualization.

[15]  FarinGerald From Conics to NURBS , 1992 .

[16]  Syh-Shiuh Yeh,et al.  Design of NURBS Curve Fitting Process on CNC Machines , 2007, 2007 American Control Conference.

[17]  Les A. Piegl,et al.  On NURBS: A Survey , 2004 .

[18]  Les A. Piegl,et al.  The NURBS Book , 1995, Monographs in Visual Communication.

[19]  Åke Björck,et al.  Numerical Methods , 2021, Markov Renewal and Piecewise Deterministic Processes.

[20]  Mahmoud Houshmand,et al.  INFELT STEP: An integrated and interoperable platform for collaborative CAD/CAPP/CAM/CNC machining systems based on STEP standard , 2010, Int. J. Comput. Integr. Manuf..

[21]  Ming-Jen Kuo,et al.  NURBS machining and feed rate adjustment for high-speed cutting of complex sculptured surfaces , 2001 .

[22]  Gang Zhao,et al.  Adaptive knot placement in B-spline curve approximation , 2005, Comput. Aided Des..

[23]  Martin Hardwick Third-generation STEP systems that aggregate data for machining and other applications , 2010, Int. J. Comput. Integr. Manuf..

[24]  Min-Yang Yang,et al.  A study on a generalized parametric interpolator with real-time jerk-limited acceleration , 2004, Comput. Aided Des..

[25]  Gerald E. Farin,et al.  From conics to NURBS: A tutorial and survey , 1992, IEEE Computer Graphics and Applications.

[26]  Hao Lan Research of whole fairing and approximation algorithm of NURBS curve: Research of whole fairing and approximation algorithm of NURBS curve , 2008 .

[27]  Chen Zichen,et al.  AXIS-BASED LOOK-AHEAD INTERPOLATOR FOR MACHINING OF SURFACES REPRESENTED BY NURBS CURVES , 2008 .

[28]  Ranga Narayanaswami,et al.  A parametric interpolator with confined chord errors, acceleration and deceleration for NC machining , 2003, Comput. Aided Des..

[29]  M. Mori,et al.  Adaptive interpolation scheme for NURBS curves with the integration of machining dynamics , 2005 .

[30]  LI De-xin Research of whole fairing and approximation algorithm of NURBS curve , 2008 .

[31]  Yusuf Altintas,et al.  High speed CNC system design. Part I: jerk limited trajectory generation and quintic spline interpolation , 2001 .

[32]  Hoda A. ElMaraghy,et al.  NURBS representation of estimated surfaces resulting from machining errors , 2009, Int. J. Comput. Integr. Manuf..

[33]  E. T. Y. Lee,et al.  Choosing nodes in parametric curve interpolation , 1989 .

[34]  Mohammed Bennamoun,et al.  Automatic Bayesian knot placement for spline fitting , 2001, Proceedings 2001 International Conference on Image Processing (Cat. No.01CH37205).

[35]  Hong-Tzong Yau,et al.  Real-time NURBS interpolator: application to short linear segments , 2009 .

[36]  H. Yau,et al.  Reverse engineering of complex geometry using rational B-splines , 1997 .

[37]  Daniel C. H. Yang,et al.  Parametric interpolator versus linear interpolator for precision CNC machining , 1994, Comput. Aided Des..

[38]  Weiyin Ma,et al.  Parameterization of randomly measured points for least squares fitting of B-spline curves and surfaces , 1995, Comput. Aided Des..

[39]  Zezhong C. Chen,et al.  A New High Precision Fitting Approach for NURBS Tool Paths Generation , 2005 .

[40]  Syh-Shiuh Yeh,et al.  Adaptive-feedrate interpolation for parametric curves with a confined chord error , 2002, Comput. Aided Des..

[41]  M. Tsai,et al.  Development of a dynamics-based NURBS interpolator with real-time look-ahead algorithm , 2007 .

[42]  Hong-Tzong Yau,et al.  PC-based Controller with Real-time Look-ahead NURBS Interpolator , 2007 .

[43]  Massimiliano Lucchesi,et al.  The Numerical Method , 2008 .

[44]  Moshe Shpitalni,et al.  Realtime curve interpolators , 1994, Comput. Aided Des..

[45]  Shi Li-min An Iterative Algorithm of NURBS Interpolation and Approximation , 2006 .

[46]  Chia-Hsiang Menq,et al.  Smooth-surface approximation and reverse engineering , 1991, Comput. Aided Des..