Apparatus and method for determining shape of end of welding bead
AssigneeSuzuki Motor Corporation
InventorsHidenobu Ishida, Naoki Ozawa, Tsukasa Hagihara, Shuichi Usui
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Abstract
An apparatus 1 of the present invention includes a laser emitting unit 2, a monitor unit 3, a storage unit 4, an image extraction unit 5, a bead recognition unit 6, and a bead shape determination unit 7. The bead shape determination unit 7 is configured to calculate the position of the end of a bead region based on the bead region recognized by the bead recognition unit 6, and to determine whether the shape of the end of the bead region is convex or concave in the extending direction of the bead region.
Claims10
An apparatus for determining the shape of an end of a welding bead formed by irradiating a weld material with a welding laser, comprising:
- a laser emitting unit for emitting the welding laser onto the weld material;
- a monitor unit for continuously capturing images of a portion on the weld material irradiated with the welding laser;
- a storage unit for storing the images captured by the monitor unit;
- an image extracting unit for extracting one of the images from the storage unit when the average luminance within the image is equal to or less than a predetermined image extracting threshold;
- a bead recognition unit for recognizing a bead region in the image extracted by the image extraction unit;
- and
- a bead shape determination unit for calculating the position of an end of the bead region based on the bead region recognized by the bead recognition unit, and for determining whether the shape of the end of the bead region is convex or concave in the extending direction of the bead region;
- wherein the bead shape determination unit includes
- a representative point calculation module for calculating a representative point of the bead region;
- a center position calculation module for calculating a center position of the end of the bead region;
- an intermediate point calculation module for calculating an intermediate point between the representative point of the bead region and the center position of the end of the bead region;
- a straight line calculation module for calculating two straight lines which extend parallel to each other on both sides of the line connecting the center position and the intermediate point, and intersect with the periphery of the end of the bead region;
- and
- a curvature calculation module for calculating intersection points between the two straight lines and the periphery of the end, calculating a degree of curvature based on the intersection points and the center position, and then determining whether the shape of the end of the bead region is convex or concave by use of the degree of curvature.
A method for determining the shape of an end of a welding bead formed by irradiating a weld material with a welding laser, comprising:
- emitting the welding laser onto the weld material;
- capturing images of a portion irradiated with the welding laser on the weld material along the time course;
- storing the images in a storage unit;
- extracting one of the images from the storage unit when the average luminance within the image is equal to or less than a predetermined image extracting threshold;
- recognizing a bead region in the image extracted from the storage unit;
- and
- calculating the position of the end of the bead region based on the recognized bead region, and determining whether the shape of the end of the bead region is convex or concave in the extending direction of the bead region,
- wherein the process for determining whether the shape of the end of the bead region is convex or concave includes
- calculating a representative point of the bead region;
- calculating a center position of the end of the bead region;
- calculating an intermediate point between the representative point of the bead region and the center position of the end of the bead region;
- calculating two straight lines which extend parallel on both sides of the line connecting the center position and the intermediate point, and intersect with the periphery of the end of the bead region;
- and
- calculating intersection points between the two straight lines and the periphery of the end, calculating a degree of curvature based on the intersection points and the center position, and then determining whether the shape of the end of the bead region is convex or concave by use of the degree of curvature.
Dependencies are inferred from the claim text.