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A new method for characterizing spindle radial error motion a two-dimensional point of view. Xiaodong Lu Special presentation at noon of Aug 25, 2009 Organized by James Bryan. Background. J. Tlusty , “System and Methods of Testing Machine Tools”, Microtecnic , 13(4):162-178, 1959.
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A new method for characterizing spindle radial errormotiona two-dimensional point of view Xiaodong Lu Special presentation at noon of Aug 25, 2009 Organized by James Bryan
Background • J. Tlusty, “System and Methods of Testing Machine Tools”, Microtecnic, 13(4):162-178, 1959. • J. Bryan, R. Clouser, and E. Holland. “Spindle Accuracy”, American Machinist, 111(25):149-164, 1967 • R. Donaldson, A Simple Method for Separating Spindle Error from Test Ball Roundness Error, CIRP Annals, Vol. 21/1, 1972 • J. Peters, P. Vanherck, An Axis of Rotation Analyser, Proc. Of 14th International MTDR Conference, 1973. • ANSI/ASME B89.3.4M – 1985, Axes of Rotation: Methods for specifying and testing, 1985. • ISO 230-7:2006, Test code for machine tools—Part 7: Geometric accuracy of axes of rotation, 2006 • J. B. Bryan, The History of Axes of Rotation and my Recollections, Proceedings of ASPE Summer Topical Meeting on Precision Bearings and Spindles, 2007. • E. R. Marsh, Precision Spindle Metrology, DEStech Publications, 2008.
Something is wrong! • Darcy Montgomery of Kodak Graphics (Vancouver) sent Email to Prof. Yusuf Altintas (UBC), questioning about ASNI B89.3.4, what if the amplitudes of once-per-revolution components in X and Y are not equal to each other? The removal of once-per-revolution component is questionable. • Darcy’s question motivated me and my students (UBC) to develop a new method for a more rigorous treatment of the spindle radial error motion.
Spindle motion analysis framework Layer 1: Test Point Motion Layer 2: Spindle Motion Layer 3: Predict Application Error: effect of spindle radial error motion on a specific application
1: Test point vector motion V[-2] V[0] V[1] V[-1] V[2] V[-2] Error Motion 2ω V[2] V[2] 2ω 2ω V[-1] V[-1] V[-1] ω ω ω ω ω ω ω V[1] V[1] V[1] V[1] V[0] V[0] V[0] V[0] V[0]
1: Test point vector motion 2ω 2ω ω ω
1: Test point vector motion Spindle rotation average point: the intersection between the spindle axis average line and the radial plane at the specified axial location Spindle rotation center: the intersection between the spindle axis of rotation and the radial plane at the specified axial location
3: Spindle error motion effect on applications Applications with two sensitive directions: Applications with single fixed sensitive direction: Applications with single rotating sensitive direction:
Once-per-revolution radial motion Y Y X X A spindle with once-pre-revolution radial error motion The perfect spindle
Once-per-revolution radial motion Y Y X X A spindle with once-pre-revolution radial error motion The perfect spindle
E-beam rotary writing machine A spindle with once-pre-revolution radial error motion
E-beam rotary writing machine A spindle with once-pre-revolution radial error motion
E-beam rotary writing machine A spindle with once-pre-revolution radial error motion
E-beam rotary writing machine A spindle with once-pre-revolution radial error motion
E-beam machine with multi-tools A spindle with once-pre-revolution radial error motion Produced pattern on a once-per-rev error spindle
Mutli-tool boring with k=2 error A spindle with K=2 radial error motion: Produced holes
Mutli-tool boring with k=2 error A spindle with K=2 radial error motion: Produced holes
Another example Spindle Error Motion: ANSI/ASME B89.3.4M
Applications with 2 sensitive directions • Machining/measuring axis-asymmetric patterns • Machining/measuring axis symmetric pattern with multiple tools installed at different radial directions