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The role of measurement and modelling of machine tools inimproving product quality

Published online by Cambridge University Press:  06 March 2014

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Abstract

Manufacturing of high-quality components and assemblies is clearly recognised byindustrialised nations as an important means of wealth generation. A “right first time”paradigm to producing finished components is the desirable goal to maximise economicbenefits and reduce environmental impact. Such an ambition is only achievable through anaccurate model of the machinery used to shape the finished article. In the first analysis,computer aided design (CAD) and computer aided manufacturing (CAM) can be used to producean instruction list of three-dimensional coordinates and intervening tool paths totranslate the intent of a design engineer into an unambiguous set of commands for amanufacturing machine. However, in order for the resultant manufacturing program toproduce the desired output within the specified tolerance, the model of the machine has tobe sufficiently accurate. In this paper, the spatial and temporal sources of error andvarious contemporary means of modelling are discussed. Limitations and assumptions in themodels are highlighted and an estimate of their impact is made. Measurement of machinetools plays a vital role in establishing the accuracy of a particular machine andcalibrating its unique model, but is an often misunderstood and misapplied discipline.Typically, the individual errors of the machine will be quantified at a given moment intime, but without sufficient consideration either for the uncertainty of individualmeasurements or a full appreciation of the complex interaction between each independentlymeasured error. This paper draws on the concept of a “conformance zone”, as specified inthe ISO 230:1 – 2012, to emphasise the need for a fuller understanding of the complexuncertainty of measurement model for a machine tool. Work towards closing the gap in thisunderstanding is described and limitations are noted.

Type
Research Article
Copyright
© EDP Sciences 2014

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References

ISO 841:2001 Industrial automation systems and integration – Numerical control of machines – Coordinate system and motion nomenclature
ISO 16907 Numerical compensation of geometric errors of machine tools
Schwenke, H., Knapp, W., Haitjema, H., Weckenmann, A., Schmitt, R., Delbressine, F., Geometric error measurement and compensation of machines – An update, CIRP Ann. Manuf. Technol. 57, 660675 (2008) CrossRefGoogle Scholar
R. Callaghan, Machine tool and motion error standardized definitions for simplified error modeling, Tech. Report (Independent Quality Labs, Inc., 2007)
Ford, D.G., Postlethwaite, S.J.R., Allen, J.P., Blake, M.D., Compensation algorithms for the real-time correction of time and spatial errors in a vertical machining centre, J. Eng. Manufact. 214, 221234 (2000) CrossRefGoogle Scholar
Lee, J.H., Liu, Y., Yang, S.H., Accuracy improvement of miniaturized machine tool: Geometric error modeling and compensation, Int. J. Mach. Tools Manufact. 46, 15081516 (2005) CrossRefGoogle Scholar
Nojedeh, M.V., Habibi, M., Arezoo, B., Tool path accuracy enhancement through geometrical error compensation, Int. J. Mach. Tools Manufact. 51, 471482 (2011) CrossRefGoogle Scholar
H. Spaan, Software error compensation of machine tools, thesis, Technical University of Eindhoven, 1995
S.R. Postlethwaite, Electronic based accuracy enhancement of CNC machine tools, Ph.D. thesis, 1992
A.P. Longstaff, S. Fletcher, A. Myers, D.G. Ford, Volumetric compensation of machine tools makes geometric errors negligible, in 3rd Int. Congress on Precision Machining, 2005, Vol. 3, pp. 209–216
ISO 230-1, 2012. Part 1: Geometric accuracy of machines operating under no-load or quasi-static conditions
A.P. Longstaff, S. Fletcher, A. Poxton, A. Myers, Comparison of Volumetric Analysis Methods for Machine Tools with Rotary Axes, LAMDAMAP 2009 (Euspen Ltd, 2009), pp. 87–96
S. Fletcher, A.P. Longstaff, A. Myers, Defining and Computing Machine Tool Accuracy, LAMDAMAP 2009 (Euspen Ltd, 2009), pp. 77–86
Wang, S.-M., Yu, H.-J., Liao, H.-W., A new high-efficiency error compensation system for CNC multi-axis machine tools, Int. J. Adv. Manufact. Technol. 28, 518526 (2006) CrossRefGoogle Scholar
Huang, D.T., Lee, J.J., On obtaining machine tool stiffness by CAE techniques, Int. J. Mach. Tools Manufact. 41, 11491163 (2001) CrossRefGoogle Scholar
S. Fletcher, A.P. Longstaff, A. Myers, Flexible modelling and compensation of machine tool thermal errors, in 20th Annual Meeting of American Society for Precision Engineering, 2005
Mian, N.S., Fletcher, S., Longstaff, A.P., Myers, A., Efficient thermal error prediction in a machine tool using finite element analysis, Meas. Sci. Technol. 22, 85107 (2011) CrossRefGoogle Scholar
Zhang, Y., Yang, J., Jiang, H., Machine tool thermal error modeling and prediction by grey neural network, Int. J. Adv. Manufact. Technol. 59, 10651072 (2012) CrossRefGoogle Scholar
A. Abdulshahed, A.P. Longstaff, S. Fletcher, A. Myers, Comparative study of ANN and ANFIS prediction models for thermal error compensation on CNC machine tools, LAMDAMAP 2013
Bringmann, B., Knapp, W., Model-based ‘chase-the-ball’ calibration of a 5-axes machining center, CIRP Ann. Manuf. Technol. 55, 531534 (2006) CrossRefGoogle Scholar
BS ISO 8636-2:2007 Machine tools – Test conditions for bridge-type milling machines – Testing of the accuracy – Part 2: Travelling bridge (gantry-type) machines
ISO 10791-3:1998 Test conditions for machining centres – Part 3: Geometric tests for machines with integral indexable or continuous universal heads (vertical Z-axis)
Forbes, A., Measurement uncertainty and optimized conformance assessment, Measurement 39, 808814 (2006) CrossRefGoogle Scholar
BIPM, IEC, IFCC, ISO, IUPAC, IUPAP and OIML 1995, Guide to the Expression of Uncertainty in Measurement (International Organisation for Standardisation, Geneva), ISBN 92-67-10188-9
Balsamo, A. et al., Evaluation of CMM uncertainty through Monte Carlo simulations, CIRP Ann. Manuf. Technol. 48, 425428 (1999) CrossRefGoogle Scholar