Evaluating the spindle error of the roundness measurement device

Abstract

Roundness measurement devices use a probe that converts the displacement into an electrical signal. In addition to the out-of-roundness information, the measurement signal can contain undesirable noise due to mechanical, electrical, thermal, and other influences that can lead to an error in the measurement result. Errors in the rotation of the measuring device spindle are often recognised as the most significant cause of deviation of roundness signal. A prevalent technique for evaluating the precision of spindle rotation entails calibration with the precise measuring sphere. The measurement results incorporate not just the form of the rotation error in the spindle but also other sources of error that can be characterized as random noise. A novel approach for eliminating random noise bias, based on the reduction of Fourier terms proposed by Haitjema and Morel, was implemented to enhance the determination of spindle error.

Keywords

• Spindle error determination
• Roundness measurement
• Random noise bias reduction
• Fourier reduction