Calibration jig, calibration method, and measurement system

A calibration jig which calibrates a measurement apparatus that measures a three-dimensional geometry of a measurement target and includes a plurality of cameras that capture the measurement target, the calibration jig comprising:

• a plurality of elements to be measured;
• and
• a frame part to which the plurality of elements to be measured are attached, wherein each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, wherein
• the label part further includes a recognition code common to the plurality of elements to be measured for recognizing that label part,
• the identification code is composed of a combination of basic components of a predetermined first shape, and
• the recognition code includes basic components of a predetermined color that is different from a color of the basic components of the first shape.

A calibration jig which calibrates a measurement apparatus that measures a three-dimensional geometry of a measurement target and includes a plurality of cameras that capture the measurement target, the calibration jig comprising:

• a plurality of elements to be measured;
• and
• a frame part to which the plurality of elements to be measured are attached, wherein each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, wherein
• the label part further includes a recognition code common to the plurality of elements to be measured for recognizing that label part,
• the identification code is composed of a combination of basic components of a predetermined first shape, and
• the recognition code includes a portion where a predetermined image is shown.

A calibration jig which calibrates a measurement apparatus that measures a three-dimensional geometry of a measurement target and includes a plurality of cameras that capture the measurement target, the calibration jig comprising:

• a plurality of elements to be measured;
• and
• a frame part to which the plurality of elements to be measured are attached, wherein each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, wherein
• the label part further includes a recognition code common to the plurality of elements to be measured for recognizing that label part,
• the recognition code and the identification code are composed of barcodes, and
• a minimum line width of the barcode of the recognition code is different from a minimum line width of the barcode of the identification code.

A calibration jig which calibrates a measurement apparatus that measures a three-dimensional geometry of a measurement target and includes a plurality of cameras that capture the measurement target, the calibration jig comprising:

• a plurality of elements to be measured;
• and
• a frame part to which the plurality of elements to be measured are attached, wherein each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, wherein
• each of the plurality of elements to be measured further includes
• a belt-shaped plate member provided around the main body part, and
• the plurality of label parts are provided on the plate member.

A calibration method that calibrates, using a calibration jig, a measurement apparatus that measures a three-dimensional geometry of a measurement target and includes a plurality of cameras that capture the measurement target, wherein

• the calibration jig comprises a plurality of elements to be measured,
• each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, and the calibration method comprises:
• a first imaging of capturing the calibration jig with a first camera so that some of first elements to be measured from among the plurality of elements to be measured are included in a field of view of the first camera, and capturing the calibration jig with a second camera, which is different from the first camera, so that some of second elements to be measured, which are different from the first elements to be measured captured by the first camera, are included in a field of view of the second camera;
• identifying the elements to be measured, including:
• identifying the first elements to be measured by analyzing the label parts of the elements to be measured from captured images captured by the first camera, and
• identifying the second elements to be measured by analyzing the label parts of the elements to be measured from captured images captured by the second camera;
• and
• identifying calibration parameters for calibrating the first camera and the second camera from positional relationships between the identified first elements to be measured and the identified second elements to be measured.

A measurement system comprising:

• a measurement apparatus that measures a three-dimensional geometry of a measurement target;
• and
• a calibration jig for calibrating the measurement apparatus, wherein the measurement apparatus comprises:
• a moving part, including at least an actuator, that has the measurement target mounted thereon and moves the measurement target;
• a light source that radiates light onto the measurement target;
• a plurality of cameras that respectively capture a plurality of different regions of the measurement target;
• and
• a controller, including at least a processor, configured to:
• measure the three-dimensional geometry of the measurement target on the basis of capturing results of the plurality of cameras;
• control the moving part and the cameras;
• and
• identify calibration parameters for calibrating a measurement result of the measurement, and
• the calibration jig comprises:
• a plurality of elements to be measured;
• and
• a frame part to which the plurality of elements to be measured are attached, wherein each of the plurality of elements to be measured includes:
• a main body part having a predetermined shape;
• and
• a plurality of label parts provided on the main body part, wherein an identification code for identifying the elements to be measured is shown on each label part, and
• the controller is further configured to:
• cause the plurality of cameras to capture subsets of the plurality of elements to be measured, the subsets being different from each other,
• analyze the label parts of the plurality of elements to be measured corresponding to each of a plurality of captured images captured by the plurality of cameras to identify positional relationships between the plurality of elements to be measured, and
• identify the calibration parameters for calibrating the plurality of cameras from the identified positional relationships of the plurality of elements to be measured.