• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.862-874
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• 1989

A phase evil method and spectrum analysis were instrument error which is originated from measurement system and the form error of standard specimens. An instrument with a rotating table supported by an air bearing is calibrated using standard specimens. The phase of standard specimens was measured 12 times on the rotating table with rotating 30 in turn and its measurement magnification was set by 100000 times. As a result of data analysis of all the observations, read out at each of 144 orientations(per 2.5) from recorded datafiles, the error of the performance of the instrument and those of the standard specimens are evaluated and a systematic deviation of the instrument is determined. In the particular instrument used in the present experiment, the deviation of the instrument is determined with the accuracy of 15nm and those of standard specimens with the accuracy of 23, 13 n, respectively. The reproducibility of the instrument is investigated, too. If the instrument is calibrated by using the above standard specimens, then the accuracy of the measurement of roundness error can be improved to about 15nm.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.3
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• pp.31-37
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• 1988

A phase different method to evaluate the instrument error of roundness measuring instrument and the form error of specimens for the calibration of the instrument is used. An instrument with a rotary table supported by an air bearing was calibrated by using the standard balls as a standard. The calibration was carried out repeatedly by setting the same ball in 12 phase angles(per 30.deg.) on the table and by recording their roundness errors with a magnification of 100,000 times. As a result of data analysis of all the observations, readout at each of 144 orientations(per 2.5.deg.) from recorded data file, the error of performance of the instrument and the specimens are separated. In the particular instrument used in the present experiment, the error of the instrument was determined with the accuracy of 0.0164 (.mu.m) and the form error of the specimens was determined with the accuracy of 0.0264,0.0172(.mu.m), respectively. If the instrument was calibrated by using the above specimens, then the accuracy of the measurement of roundness error can be improved to about 0.017 (.mu.m).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.3
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• pp.69-75
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• 2017

There are two types of expensive measuring instruments currently on the market shape measurement and roundness measurement instruments. As they are very expensive, from tens of millions to more than 200 million won, buying them is economically burdensome for small companies or individuals. Therefore, in order to integrate the shape and roundness measurements into a single transfer device, this study aimed to reduce the trial and error by 3D modeling and simulation, and we confirmed the feasibility of operation. Based on these outcomes, a prototype hybrid measuring instrument was fabricated. As a result of performance evaluation and comparative evaluation, we verified the feasibility of implementation and application of the hybrid measuring instrument.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04a
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• pp.637-642
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• 1995

For measuring the error motion of ultra-precision spindle, eliminating the geometric errors is a must. Unless it is achieved, geometric errors will be dominant in data. Here, the roundness error and alignment error between spindle and sensor are to be removed. That's because typical error range of such spindle is muchless than geometric one. A capacitive transducer of cylidricalshape was developed, which takes full advantage of the spatial-averaging effect by using large area compared tpo the geometric error. This idea was first proposed by Chapman and here it is modified for better performance with nomical gap of 50 .mu. m and with newly designed guards which encompass the respective sensor to rectify the electrical field distribution in good shape. The measurement system is made to get the orbit of Ultra-Precision Air Spindle which is supposed to have its runout under 1 .mu. m. The Calibration data of this sensor is presented and the spindle orbit from 2000rpm to 5500rpm is showed. It is quite reasonable to use this sensor in the range of 60 .mu. m with an accuracy of several tens of nm.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.2
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• pp.17-23
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• 2002

A cylindrical capacitance-type spindle displacement sensor was developed and its effectiveness as a system to monitor cutting forces during hard turning was tested in this research. The sensor was installed between the face of spindle cover and the chucking element and measured pure radial motion of the spindle under the condition with presence of roundness error at measured surface. To prove the effectiveness of the developed system hard aiming tests using ceramic inserts and tool steel as workpiece were conducted. The workpiece was hardened up to 65 Rc. The variations of pure radial motion of the spindle ware measured during the cutting tests. The signals from the sensor showed the same pattern of cutting force variations from the tool dynamometer due to the progress of tool wear. As the flank wear of the ceramic tool increased both static component of cutting forces and the amount of center shift of spindle orbit increased, Results from the research showed that the developed sensor could be utilized as an effective and cheap on-line sensing device to monitor cutting conditions and tool performance in the un-manned machining center.