三次元デジタイザによる寸法測定条件の最適化

抄録

In recent years, the 3D digitizer has been used for shape measurement of Reverse Engineering for creating 3D CAD data from actual items such as molds without drawings. The 3D digitizer has merit of being able to measure a complex shape in 3D in a short time, but because it creates 3D data from the images taken by camera, the measurement accuracy is lower than Coordinate Measuring Machine. In addition, at the time of measurement, usually, 3D data of the measured object is created by combining the measured data taken in multiple shots front, side, and top surface, etc. Usually , the accuracy of the 3D digitizer offered by manufacturer is represents the accuracy of measurement in of 1 shot , the measurement accuracy of the 3D data created by combining multiple shots data is often not clarified. In this study, we aim to clarify and improve measurement accuracy of the 3D digitizer, we did experiments that aim to clarify the parameter of measurement conditions that influence the measurement accuracy using L18 array by Taguchi method. As a result, we found that the effective parameters that influence the measurement accuracy are the number of camera shots, the position of the measured object, the exposure time, and the reference points. Also, we measured a metal block under the optimum conditions, and the measurement error was 1/8 or less compared with the conventional conditions.