Offline adaptive control

CNC machining is the only option for rapid manufacturing of components with stringent quality requirements. But the bottleneck to CNC machining is the generation of fool-proof CNC programs. While the CNC programmer is able to generate the correct cutter paths using CAM systems, it is not as easy with the cutting parameters. Adaptive control is able to overcome this difficulty but it requires expensive online force measurements. An alternative is to predict the cutting forces offline from the geometry, kinematics, material properties and cutting parameters. A process model developed for this calculates the optimal cutting parameters at any instant from the contact surface between the cutter and work piece. This hybrid model captures the invariant characteristics of the process in six cutting coefficients determined through simple experiments. This model is applicable to complex machining involving the generic cutter and motions up to five degrees of freedom.

[1]  E. Eleftheriou,et al.  Analysis of the Mechanics of Machining with Tapered End Milling Cutters , 1994 .

[2]  K. P. Karunakaran,et al.  A solid model-based off-line adaptive controller for feed rate scheduling for milling process , 2008 .

[3]  Yusuf Altintas,et al.  Mechanics and dynamics of general milling cutters.: Part I: helical end mills , 2001 .

[4]  Yusuf Altintas,et al.  CAD Assisted Adaptive Control for Milling , 1991 .

[5]  Richard E. DeVor,et al.  Mechanistic Modeling of the Ball End Milling Process for Multi-Axis Machining of Free-Form Surfaces , 2001 .

[6]  Dong-Woo Cho,et al.  3D Ball-End Milling Force Model Using Instantaneous Cutting Force Coefficients , 2005 .

[7]  Minyang Yang,et al.  The prediction of the cutting force in ball-end milling with a flexible cutter , 1993 .

[8]  Roger S. Pressman,et al.  Numerical Control and Computer-Aided Manufacturing , 1977 .

[9]  F. Koenigsberger,et al.  An investigation into the cutting force pulsations during milling operations , 1961 .

[10]  Weihong Zhang,et al.  Efficient calibration of instantaneous cutting force coefficients and runout parameters for general end mills , 2007 .

[11]  Klaus Weinert,et al.  Mechanistic identification of specific force coefficients for a general end mill , 2004 .

[12]  Lihui Wang,et al.  Simplified and efficient calibration of a mechanistic cutting force model for ball-end milling , 2004 .

[13]  L. N. López de Lacalle,et al.  CALCULATION OF THE SPECIFIC CUTTING COEFFICIENTS AND GEOMETRICAL ASPECTS IN SCULPTURED SURFACE MACHINING , 2005 .

[14]  W. P. Wang,et al.  Solid modeling for optimizing metal removal of three-dimensional NC end milling , 1988 .

[15]  E.J.A. Armarego,et al.  Computer Based Modelling of Popular Machining Operations for Force and Power Prediction , 1985 .