Target and system for three-dimensionally measuring position and attitude using said target

A system for enabling a position and an attitude occupied by an object to be three-dimensionally measured from a measuring point remote from said object, wherein said system comprises:

• a mark for indicating four or more different points on a single common plane;
• a target including a spherical reflector of which the center of curvature is located remote from said common plane;
• means for irradiatiang a light toward said target;
• image building means for building up an image representing said target;
• image photographing means for photographing said image representing said target;
• means for extracting from said image representing said target mark image portions representing said mark and a point image portion representing a bright point formed by said spherical reflector;
• means for detecting a coordinate value corresponding to the center of gravity of said mark image portions representing said mark and a coordinate value corresponding to the center of gravity of said point image portion representing said bright point;
• and
• calculating means for determining in three dimensions said position and said attitude occupied by said object via a series of calculations based on said coordinate values.

A method of measuring position and attitude of an object from a remote measuring point, comprising the steps of:

• providing the object with a target having a mark embedded in and not extending beyond a surface of the target, the mark defining at least four fixed coplanar points and having a concave spherical reflector embedded in and not extending beyond the surface of the target, the spherical reflector having a center of curvature located in a fixed non-coplanar positional relationship with the mark;
• illuminating the target;
• forming an image of the illuminated target;
• and
• calculating position and attitude of the target on the basis of locations in the image of portions corresponding to the mark and the spherical reflector.

A target for measuring in three dimensions a position and an attitude occupied by an object from a measuring point remote from said object, wherein said target comprises:

• a mark including means defining at least four points disposed respectively at different positions and in a common plane;
• and
• a spherical reflector having a center of curvature located at a position remote from said common plane;
• said mark including,
• a first group of said points disposed outside of said spherical reflector;
• and
• a second group of said points disposed within said spherical reflector.

A target for measuring in three dimensions a position and an attitude occupied by an object from a measuring point remote from said object, wherein said target comprises:

• a mark including means defining at least four points disposed respectively at different positions and in a common plane, embedded in the target and not extending beyond a surface thereof;
• and
• a spherical reflector having a center of curvature located at a position remote from said common plane, embedded in the target and not extending beyond a surface thereof;
• said mark including,
• a first group of said points disposed on a circular locus having a first radius;
• and
• a second group of said points disposed on a second circular locus having a second radius.

A target for indicating a position and an attitude of an object to a measuring device remote from the object, the target comprising:

• a body;
• at least four distinct and all spacedly disposed means connected to the body, embedded in and not extending beyond a surface thereof, each of the at least four means for indicating a location to the measuring device, and the indicated locations defining a single common plane;
• and
• a concave spherical reflector connected to the body, embedded in and not extending beyond a surface thereof, and having a center of curvature disposed at a fixed location remote from the single common plane.