| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for extracting cylinder information from a measurement point for surely creating cylinder data from a measurement point on a cylinder surface and allowing an accurate approximation. <P>SOLUTION: The method includes determining a center of a sphere from the measurement point first, then projecting the measurement point after determining a projection direction by using the center of the sphere as a preliminary central point of the cylinder and varying two angles, selecting an angle where the total sum of square of distances between the circumference and the projected measurement point is minimum, then improving the accuracy of the angle with convergent calculation, and finally determining an angle and a central point of a circle where the total sum of square of distances between the circumference and the projected measurement point is minimum by using the angle with the improved accuracy and a value obtained by projecting the preliminary central point with the angle as an initial value of the center of the cylinder. Thus a radius, a center, and a central axis of the cylinder are obtained accurately and in a short time period. <P>COPYRIGHT: (C)2012,JPO&INPIT |
