Abstract:A circle can be defined as the intersection of a sphere and a plane, where the plane is determined by three arbitrary points. Then the line passes through the center of the circle and the sphere is perpendicular to the circle’s plane. In this paper, we propose a spherical target extraction approach based on these spherical geometry relations. Our algorithm extracts several intersection circles from the point cloud under the predefined constraints, then the center and radius of the spherical target can be determined by minimizing the sum of the distances from the sphere center to the normal vectors of the circles. Experimental comparison with other approaches based on least squares, total least squares and weighted least squares, shows that our spherical target extraction approach is able to achieve higher accuracy and robustness.