Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor

D. Clough, S. Fletcher, A. P. Longstaff, P. Willoughby

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Increasing demand on manufacturing industry to produce tighter tolerance parts at a consistent rate means it is necessary to gain a greater understanding of machine tool capabilities, error sources and factors affecting asset availability. The machine tool spindle can be a significant contributor to both machine tool errors and failures resulting in a requirement for spindle error measurement. The use of eddy current non-contact displacement transducers is currently a popular method for measuring spindle error in a manufacturing environment. This is due to their resistance to harsh conditions where dust and coolant may be present. Unfortunately, many eddy current sensors have non-linear outputs that vary with target material and dimension. Typically, adjustments in the signal conditioning are provided to linearise the output, and calibrate the sensors for a specific target material. It is the purpose of this paper to assess current sensor calibration methods and highlight the potential for error in practical situations. To solve the problem, a method of in-situ calibration is presented, which uses the short range positional accuracy of the machine as a reference and least squares best fit of a low order polynomial. Validation is provided through the use of calibration test results and a practical example.

Original languageEnglish
Title of host publicationProceedings of the 37th International MATADOR Conference
EditorsSrichand Hinduja, Lin Li
PublisherSpringer
Chapter7
Pages281-284
Number of pages4
ISBN (Electronic)9781447144809
ISBN (Print)9781447144793, 9781447158592
Publication statusPublished - 9 Oct 2012
Event37th International MATADOR 2012 Conference - Manchester, United Kingdom
Duration: 25 Jul 201227 Jul 2012

Conference

Conference37th International MATADOR 2012 Conference
CountryUnited Kingdom
CityManchester
Period25/07/1227/07/12

Fingerprint

Eddy currents
Machine tools
Calibration
Sensors
Costs
Measurement errors
Coolants
Dust
Transducers
Signal processing
Polynomials
Availability
Industry

Cite this

Clough, D., Fletcher, S., Longstaff, A. P., & Willoughby, P. (2012). Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor. In S. Hinduja, & L. Li (Eds.), Proceedings of the 37th International MATADOR Conference (pp. 281-284). Springer.
Clough, D. ; Fletcher, S. ; Longstaff, A. P. ; Willoughby, P. / Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor. Proceedings of the 37th International MATADOR Conference. editor / Srichand Hinduja ; Lin Li. Springer, 2012. pp. 281-284
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Clough, D, Fletcher, S, Longstaff, AP & Willoughby, P 2012, Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor. in S Hinduja & L Li (eds), Proceedings of the 37th International MATADOR Conference. Springer, pp. 281-284, 37th International MATADOR 2012 Conference, Manchester, United Kingdom, 25/07/12.

Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor. / Clough, D.; Fletcher, S.; Longstaff, A. P.; Willoughby, P.

Proceedings of the 37th International MATADOR Conference. ed. / Srichand Hinduja; Lin Li. Springer, 2012. p. 281-284.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Clough D, Fletcher S, Longstaff AP, Willoughby P. Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor. In Hinduja S, Li L, editors, Proceedings of the 37th International MATADOR Conference. Springer. 2012. p. 281-284