Patent ID: 10083542

Abstract:
Polyhedral data is compared with limited information while keeping accuracy. A comparison of two polyhedrons is accomplished as follows. (1) A squared-sum of the difference of primary moment functions and a squared-sum of the difference of secondary moment functions are separately sought at sample points of polyhedron Ma, Mb, normalize them and compute the sum of both, or seek sum functions of the primary moment functions and the secondary moment functions to compute the squared-sum of the difference of the sum functions, the primary moment function all the sample points of polyhedral data that occupy central symmetry directions are blended in the same sign, which is the different sign in the case of the secondary moment function, the functions having variables representing points on a surface of a sphere of which center is the center of gravity of the polyhedron and a value which is an axial moment value, the axis defined as a line through the points and the center, and (2) in the case that the value of the sum is a certain threshold or less, it is determined that the polyhedrons are similar in shape.