The contact breaker points where touch with the tangent and the curved line of aforementioned given where contact breaker points specific manner, tangent creation manner and

摘要

PPROBLEM TO BE SOLVED: To provide a contact point identification method and the like capable of more appropriately identifying a contact point. PSOLUTION: The contact point identification method includes: an axial line generation step of generating an axial line not included in a plane passing through a given point and including a curve; a spiral start point setting step of setting a spiral start point at a position not in the plane and distant from an axial line which is more distant from a most distant point from the axial line on a given curve; a three-dimensional spiral generation step of generating a three-dimensional spiral with the axial line as its axis from the spiral start point; a twisted face generation step of generating a twisted face collecting perpendicular lines drawn from respective points on the three-dimensional spiral to the axial line; a projected curve generation step of generating a projected curve obtained by projecting a given curve on the twisted face in a direction parallel with the axial line; and a contact point identification step of extracting, on the projected curve, a shortest point passing through the spiral start point and having a shortest distance from a reference plane orthogonal to the axial line, and setting a point on which the shortest point is projected on a curve in a direction parallel with an axial curve as a contact point. PCOPYRIGHT: (C)2010,JPO&INPIT