Method to Measure Curve Shape Similarities and to Generate Similar Curves

摘要

Similar curve generation technique is strongly required to design a curve in computer aided industrial design. A method to measure shape similarity of the curves and a method to generate a similar curve has been developed to meet this requirement. A parametric curve consists of multi curve segments in general. Therefore, methods to measure entire curve matching and curve segment matching, which is partial matching, are needed. Curve shape similarity measurement is described by introducing the discrete Fourier transformation. The radius of curvature distribution against arc length is analyzed by the discrete Fourier transformation. Using the Fourier coefficients, the spectra for each curve are calculated. Using the difference of the spectrum, similarity between the two curves can be calculated. A similar curve which has the feature of the reference curve is generated using the specified number of frequency by the inverse discrete Fourier transformation.