Method, apparatus and system for measuring a welding-groove position

• US 7,657,082 B2
• Filed: 01/18/2006
• Issued: 02/02/2010
• Est. Priority Date: 01/18/2005
• Status: Expired due to Fees

• Current Assignee: Kawasaki Jukogyo Kabushiki Kaisha, Central Motor Wheel Company Limited (Toyota Motor Corporation)
• Original Assignee: Kawasaki Jukogyo Kabushiki Kaisha, Central Motor Wheel Company Limited (Toyota Motor Corporation)
• Inventors: Kubo, Sadao, Uehara, Hirotaka, Shimada, Tadao, Kinoshita, Hirotaka, Suzuki, Yukimitsu, Arita, Ichiro, Onoue, Kazuhiko
• Primary Examiner(s): Mehta; Bhavesh M
• Assistant Examiner(s): DULANEY, KATHLEEN YUAN
• Application Number:
  US11/335,173
• Publication Number:
  US 20060159331A1
• Time in Patent Office: 1,476 Days
• Field of Search: 382/154, 228/101, 356/12, 219/121.63
• US Class Current: 382/154
• CPC Class Codes: B23K 9/1274 Using non-contact, optical means, e.g. laser means

Abstract

A method of measuring a welding-groove position for an over-lapped fillet welding of thin members, comprising a projection step of projecting a slit light so that the slit light is projected on both the thin members crossing a welding-groove face, a two-dimensional image acquisition step of capturing the slit-light image projected on each of the thin members as two-dimensional images; a three-dimensional conversion step of converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter, and a calculation step of calculating the welding-groove position based on the three-dimensional data of the projected slit-light images, and relative positions between the projected slit-light images in the three-dimensional data defined by shapes and arrangement of the thin members.

Claims

1. A method of measuring a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member with a measuring apparatus, comprising steps of:

projecting, with a projection module of the measuring apparatus, a slit light on both the first thin member and the second thin member crossing a welding-groove face;

capturing, with a two-dimensional image acquisition module of the measuring apparatus, a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

converting, with a three-dimensional conversion module of the measuring apparatus, the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

calculating, with a calculation module of the measuring apparatus, the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface,

projecting the slit light includes projecting the slit light substantially in parallel with the welding-groove face,

capturing the slit-light image includes capturing a first slit-light image and a second slit-light image as the two-dimensional images so that the first slit-light image projected on the first projection surface of the first thin member, and the second slit-light image projected on the second projection surface of the second thin member are arranged spaced apart and substantially in parallel with each other in a captured image, and

calculating the welding-groove position includes;

calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

calculating a position of an end point of the second approximated straight line on a side of a welding groove based on the equation for the second approximated straight line;

calculating an equation for a third straight line that passes through the end point, and is substantially perpendicular to the second approximated straight line, and is intersectable with the first approximated straight line; and

calculating an intersecting point of the first approximated straight line and the third straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the third straight line.

2. A method of measuring a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member with a measuring apparatus, comprising steps of:

projecting, with a projection module of the measuring apparatus, a slit light on both the first thin member and the second thin member crossing a welding-groove face;

capturing, with a two-dimensional image acquisition module of the measuring apparatus, a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

converting, with a three-dimensional conversion module of the measuring apparatus, the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

calculating, with a calculation module of the measuring apparatus, the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface,

projecting the slit light includes projecting the slit light inclined to the welding-groove face,

capturing the slit-light image includes capturing a first slit-light image, a second slit-light image, and a third slit-light image as the two-dimensional images, so that the first slit-light image projected on the first projection surface of the first thin member and the second slit-light image projected on the second projection surface of the second thin member are arranged spaced apart and substantially in parallel with each other in a captured image, and the third slit-light image projected on the welding-groove face is arranged between the first slit-light image and the second slit-light image in the captured image, and

calculating the welding-groove position includes;

calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

calculating a position of a predetermined point on the third slit-light image based on three-dimensional data corresponding to the third slit-light image;

calculating an equation for a fourth straight line that is substantially perpendicular to the second approximated straight line, and passes through the predetermined point; and

calculating an intersecting point of the first approximated straight line and the fourth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fourth straight line.

3. A method of measuring a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member with a measuring apparatus, comprising steps of:

projecting, with a projection module of the measuring apparatus, a slit light on both the first thin member and the second thin member crossing a welding-groove face;

capturing, with a two-dimensional image acquisition module of the measuring apparatus, a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

converting, with a three-dimensional conversion module of the measuring apparatus, the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

calculating, with a calculation module of the measuring apparatus, the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is inclined to the first projection surface and the second projection surface,

capturing the slit-light image includes capturing a first slit-light image, a second slit-light image, and a third slit-light image as the two-dimensional images, so that the first slit-light image projected on the first projection surface of the first thin member and the second slit-light image projected on the second projection surface of the second thin member are arranged spaced apart and substantially in parallel with each other in a captured image, and the third slit-light image projected on the welding-groove face is arranged between the first slit-light image and the second slit-light image in the captured image, and

calculating the welding-groove position includes;

calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

calculating a position of a first end point of the first approximated straight line on a first side of a welding groove based on the equation for the first approximated straight line;

calculating a position of a second end point of the second approximated straight line on a second side of the welding groove based on the equation for the second approximated straight line;

calculating an equation for a fifth straight line of the third slit-light image between the position of the first end point and the position of the second end point based on three-dimensional data corresponding to the third slit-light image; and

calculating an intersecting point of the first approximated straight line and the fifth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fifth straight line.

4. One or more storage devices holding instructions executable by a computing device to measure a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member, the one or more storage devices comprising:

a projection module for projecting a slit light on both the first thin member and the second thin member crossing a welding-groove face;

a two-dimensional image acquisition module for capturing a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

a three-dimensional conversion module for converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

a calculation module for calculating the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface,

the projection module is configured to project the slit light substantially in parallel with the welding-groove face,

the two-dimensional image acquisition module is configured to capture a first slit-light image and a second slit-light image as the two-dimensional images, so that the first slit-light image projected on the first projection surface of the first thin member, and the second slit-light image projected on the second projection surface of the second thin member are spaced apart and substantially in parallel with each other in a captured image,

the calculation module includes;

a module for calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

a module for calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

a module for calculating a position of an end point of the second approximated straight line on a side of a welding groove based on the equation for the second approximated straight line;

a module for calculating an equation for a third straight line that passes through the end point, and is substantially perpendicular to the second approximated straight line, and is intersectable with the first approximated straight line; and

a module for calculating an intersecting point of the first approximated straight line and the third straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the third straight line.

5. The one or more storage devices of claim 4, further comprising a line-of-sight toggle module for changing a line-of-sight of one or more of the projection module and the two-dimensional image acquisition module with respect to the welding-groove face, based on the relative positions.

6. The one or more storage devices of claim 4, wherein the projection module and the two-dimensional image acquisition module are integrated as a laser sensor.

7. One or more storage devices holding instructions executable by a computing device to measure a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member, the one or more storage devices comprising:

a projection module for projecting a slit light on both the first thin member and the second thin member crossing a welding-groove face;

a two-dimensional image acquisition module for capturing a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

a three-dimensional conversion module for converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

a calculation module for calculating the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface,

the projection module is configured to project the slit light inclined to the welding-groove face,

the two-dimensional image acquisition module is configured to capture a first slit-light image, a second slit-light image, and a third slit-light image as the two-dimensional images, so that the first slit-light image projected on the first projection surface of the first thin member and the second slit-light image projected on the second projection surface of the second thin member are spaced apart and substantially in parallel with each other in a captured image, and the third slit-light image projected on the welding-groove face is arranged between the first slit-light image and the second slit-light image in the captured image,

the calculation module includes;

a module for calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

a module for calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

a module for calculating a position of a predetermined point on the third slit-light image based on three-dimensional data corresponding to the third slit-light image;

a module for calculating an equation for a fourth straight line that is substantially perpendicular to the second approximated straight line, and passes through the predetermined point; and

a module for calculating an intersecting point of the first approximated straight line and the fourth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fourth straight line.

8. The one or more storage devices of claim 7, further comprising a line-of-sight toggle module for changing a line-of-sight of the projection module and/or the two-dimensional image acquisition module with respect to the welding-groove face, based on the relative positions.

9. The one or more storage devices of claim 7, wherein the projection module and the two-dimensional image acquisition module are integrated as a laser sensor.

10. One or more storage devices holding instructions executable by a computing device to measure a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member, the one or more storage devices comprising:

a projection module for projecting a slit light on both the first thin member and the second thin member crossing a welding-groove face;

a two-dimensional image acquisition module for capturing a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

a three-dimensional conversion module for converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

a calculation module for calculating the welding-groove position based on three-dimensional data corresponding to the three dimensional images, and relative positions between the three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein when the welding-groove face is inclined to the first projection surface and the second projection surface,

the two-dimensional image acquisition module is configured to capture a first slit-light image, a second slit-light image, and a third slit-light image as the two-dimensional images, so that the first slit-light image projected on the first projection surface of the first thin member and the second slit-light image projected on the second projection surface of the second thin member are arranged spaced apart and substantially in parallel with each other in a captured image, and the third slit-light image projected on the welding-groove face is arranged between the first slit-light image and the second slit-light image in the captured image,

the calculation module includes;

a module for calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image;

a module for calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image;

a module for calculating a position of a first end point of the first approximated straight line on a first side of a welding groove based on the equation for the first approximated straight line;

a module for calculating a position of a second end point of the second approximated straight line on a second side of the welding groove based on the equation for the second approximated straight line;

a module for calculating an equation for a fifth straight line of the third slit-light image between the position of the first end point and the position of the second end point based on three-dimensional data corresponding to the third slit-light image; and

a module for calculating an intersecting point of the first approximated straight line and the fifth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fifth straight line.

11. The one or more storage devices of claim 10, further comprising a line-of-sight toggle module for changing a line-of-sight of one or more of the projection module and the two-dimensional image acquisition module with respect to the welding-groove face, based on the relative positions.

12. The one or more storage devices of claim 10, wherein the projection module and the two-dimensional image acquisition module are integrated as a laser sensor.

13. An apparatus, comprising:

a plurality of welding-groove position measuring apparatuses including one or more storage devices holding instructions executable by a computing device to measure a welding-groove position for an over-lapped fillet welding of at least a first thin member and a second thin member, each of the welding-groove position measuring apparatuses including;

a projection module for projecting a slit light on both the first thin member and the second thin member crossing a welding-groove face;

a two-dimensional image acquisition module for capturing a slit-light image projected on each of a first projection surface of the first thin member and a second projection surface of the second thin member as two-dimensional images;

a three-dimensional conversion module for converting the two-dimensional images into three-dimensional images using a predetermined three-dimensional conversion parameter; and

a calculation module for calculating the welding-groove position based on three-dimensional data corresponding to the three-dimensional images, and relative positions between three-dimensional images in the three-dimensional data defined by shapes and arrangement of both the first thin member and the second thin member;

wherein, in a first welding-groove position measuring apparatus of the welding-groove position measuring apparatuses, when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface, the projection module is configured to project the slit light substantially in parallel with the welding-groove face, the two-dimensional image acquisition module is configured to capture a first slit-light image and a second slit-light image as the two-dimensional images so that the first slit-light image projected on the first projection surface of the first thin member, and the second slit-light image projected on the second projection surface of the second thin member are spaced apart and substantially in parallel with each other in a captured image, and the calculation module is configured to execute a module for calculating an equation for a first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image, a module for calculating an equation for a second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image, a module for calculating a position of a second end point of the second approximated straight line on a second side of a welding groove based on the equation for the second approximated straight line, a module for calculating an equation for a third straight line that passes through the second end point, and is substantially perpendicular to the second approximated straight line, and is intersectable with the first approximated straight line, and a module for calculating an intersecting point of the first approximated straight line and the third straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the third straight line;

wherein, in a second welding-groove position measuring apparatus of the welding-groove position measuring apparatuses, when the welding-groove face is substantially perpendicular to the first projection surface and the second projection surface, the projection module is configured to project the slit light inclined to the welding-groove face, the two-dimensional image acquisition module is configured to capture said first slit-light image, said second slit-light image, and a third slit-light image as the two-dimensional images, so that the third slit-light image projected on the welding-groove face is arranged between the first slit-light image and the second slit-light image in the captured image, and the calculation module is configured to execute a module for calculating the equation for the first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image, a module for calculating the equation for the second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image, a module for calculating a position of a predetermined point on the third slit-light image based on three-dimensional data corresponding to the third slit-light image, a module for calculating an equation for a fourth straight line that is substantially perpendicular to the second approximated straight line, and passes through the predetermined point, and a module for calculating an intersecting point of the first approximated straight line and the fourth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fourth straight line;

wherein, in a third welding-groove position measuring apparatus of the welding-groove position measuring apparatuses, when the welding-groove face is inclined to the first projection surface and the second projection surface, the two-dimensional image acquisition module is configured to capture said first slit-light image, said second slit-light image, and said third slit-light image as the two-dimensional images, and the calculation module is configured to execute a module for calculating the equation for the first approximated straight line of the first slit-light image based on three-dimensional data corresponding to the first slit-light image, a module for calculating the equation for the second approximated straight line of the second slit-light image based on three-dimensional data corresponding to the second slit-light image, a module for calculating a position of a first end point of the first approximated straight line on a first side of the welding groove based on the equation for the first approximated straight line;

a module for calculating the position of the second end point of the second approximated straight line on the second side of the welding groove based on the equation for the second approximated straight line, a module for calculating an equation for a fifth straight line of the third slit-light image between the position of the first end point and the position of the second end point based on three-dimensional data corresponding to the third slit-light image, and a module for calculating an intersecting point of the first approximated straight line and the fifth straight line as the welding-groove position based on the equation for the first approximated straight line and the equation for the fifth straight line; and

wherein the apparatus further comprises;

a reception module for receiving a user input relating to a selection of one of the welding-groove position measuring apparatuses corresponding to the first thin member and the second thin member to be measured; and

a toggle module for switching to the one of the welding-groove position measuring apparatuses based on the user input.