抄録
A new method for measuring the roundness of a cylindrical ground part is developed. The roundness is measured on a cylindrical grinder by a practical measuring apparatus which has two displacement detectors. The obtained signals are expanded in the Fourier series, and separated into the roundness and the error motion. The calculated result of the roundness agrees approximately with a result measured by a roundness meter. A cause of the difference is disagreement of three undulation spectra. A new method to separate the three undulation spectra into the roundness and the error motion is introduced, and the calcuilated results agree well with the results measured by a roundness meter. Consequently a possibility of in-process roundness measuring of cylindrical ground parts is indicated.