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 contributionpeer-review

1 Citation (Scopus)


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
Number of pages4
ISBN (Electronic)9781447144809
ISBN (Print)9781447144793, 9781447158592
Publication statusPublished - 9 Oct 2012
Event37th International MATADOR Conference - University of Manchester , Manchester, United Kingdom
Duration: 25 Jul 201227 Jul 2012
Conference number: 37 (Link to Call for Papers)


Conference37th International MATADOR Conference
Abbreviated titleMATADOR 2012
Country/TerritoryUnited Kingdom
Internet address


Dive into the research topics of 'Practical in-situ calibration method for the non-linear output from a low cost eddy current sensor'. Together they form a unique fingerprint.

Cite this