Optical-based weld travel speed sensing system

• US 9,522,437 B2
• Filed: 01/14/2013
• Issued: 12/20/2016
• Est. Priority Date: 02/10/2012
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Pfeifer, Kyle Andrew, Holverson, Todd Earl, Watson, William Todd, Hutchison, Richard Martin, Becker, William Joshua
• Primary Examiner(s): Ross, Dana
• Assistant Examiner(s): Teaters, Lindsey C
• Application Number:
  US13/740,964
• Publication Number:
  US 20130206740A1
• Time in Patent Office: 1,436 Days
• Field of Search: 219/121.11, 219/121.83, 219/122, 219/124.1, 21912431-12434, 219/124.5, 356/27, 356/28, 356/28.5
• US Class Current: 1/1
• CPC Class Codes: B23K 9/095 Monitoring or automatic control of welding parameters
• CPC Class Codes: B23K 9/0953 using computing means
• CPC Class Codes: B23K 9/0956 using sensing means, e.g. optical
• CPC Class Codes: G01P 3/36 Devices characterised by the use of optical means, e.g. using infrared, visible, or ultraviolet light G01P3/68 takes precedence; gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams G01C19/64
• CPC Class Codes: G01P 3/38 using photographic means
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 11/14 using ultrasonic, sonic, or infrasonic waves
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems

Abstract

A travel speed sensing system includes an optical sensor configured to be coupled to a welding torch. The optical sensor is configured to sense light incident on the optical sensor, and the travel speed sensing system is configured to determine a travel speed of the welding torch, a direction of the welding torch, or both, based on the sensed light.

Claims

1. A travel speed sensing system, comprising:

an optical sensor configured to be coupled to a welding torch, wherein the optical sensor is configured to sense light incident on the optical sensor, and wherein the travel speed sensing system is configured to determine a travel speed of the welding torch, a direction of the welding torch, or both, based on the sensed light, the optical sensor is configured to acquire images of a surface in a weld area, the travel speed sensing system is configured to determine the travel speed of the welding torch based on the images, and the optical sensor comprises a range finding mechanism configured to determine a distance from the optical sensor to the surface, and wherein the travel speed sensing system is configured to determine the travel speed based on the distance.

2. The travel speed sensing system of claim 1, wherein the travel speed sensing system is configured to determine the travel speed using optical flow algorithms applied to the images acquired via the optical sensor.

3. The travel speed sensing system of claim 1, wherein the surface is augmented by application of a visible pattern to the surface, and the optical sensor is configured to determine the travel speed of the welding torch based on the visible pattern.

4. The travel speed sensing system of claim 1, comprising a positioning mechanism configured to maintain the optical sensor at a specific distance relative to the surface in the weld area across a range of angles of the welding torch relative to a workpiece, across a range of distances of the welding torch relative to the workpiece, or both.

5. The travel speed sensing system of claim 1, comprising an optical surface motion sensor having the optical sensor and a light source, wherein the optical surface motion sensor is configured to:

output light toward the surface in the weld area via the light source; and

sense light reflected from the surface via the optical sensor.

6. The travel speed sensing system of claim 5, comprising:

a first optical fiber configured to carry the light output from the light source toward the surface; and

a second optical fiber configured to carry the light reflected from the surface to the optical sensor.

7. The travel speed sensing system of claim 5, wherein the optical surface motion sensor is configured to filter the light reflected from the surface via a filter to produce a filtered light at one or more desired frequencies, and sense the filtered light via the optical sensor.

8. The travel speed sensing system of claim 1, comprising multiple optical sensors coupled to different sides of the welding torch, wherein the multiple optical sensors are configured to provide surface motion information for determining the travel speed of the welding torch.

9. The travel speed sensing system of claim 1, comprising a sensor disposed on the welding torch, wherein the sensor is configured to sense a parameter indicative of an angle of the welding torch, and wherein the travel speed sensing system is configured to determine the travel speed based in part on the sensed parameter.

10. The travel speed sensing system of claim 1, comprising a protective covering disposed over the optical sensor to shield the optical sensor from weld spatter.

11. A welding torch assembly, comprising:

a welding torch configured to generate a welding arc between the welding torch and a workpiece;

an optical sensor coupled to the welding torch and configured to output a signal indicative of light sensed by the optical sensor to a travel speed sensing system, wherein the travel speed sensing system is configured to determine a travel speed of the welding torch based on the signal; and

a positioning mechanism coupled to the welding torch and the optical sensor, wherein the positioning mechanism is configured to maintain the optical sensor at a specific distance relative to a surface in a weld area across a range of angles of the welding torch relative to the workpiece, across a range of distances of the welding torch relative to the workpiece, or both.

12. The welding torch assembly of claim 11, wherein the optical sensor is configured to sense light reflected from the surface in the weld area.

13. The welding torch assembly of claim 12, comprising a surface motion sensing module coupled to the welding torch, wherein the surface motion sensing module comprises a light source to output light to the surface and the optical sensor to sense light reflected from the surface.

14. The welding torch assembly of claim 13, comprising:

a first optical fiber configured to carry the light output from the light source toward the surface; and

a second optical fiber configured to carry the light reflected from the surface to the optical sensor.

15. The welding torch assembly of claim 11, wherein the optical sensor comprises a camera configured to acquire images of the surface in the weld area, and the signal output from the camera to the travel speed sensing system comprises image data.

16. The welding torch assembly of claim 15, wherein the camera maintains a line of sight that is substantially parallel with a tip of the welding torch.

17. The welding torch assembly of claim 15, wherein the travel speed sensing system is configured to process the images acquired via the camera to determine an image with a desired exposure and to adjust an exposure time of the camera based on the desired exposure.

18. A travel speed sensing system, comprising:

an optical sensor configured to be coupled to a welding torch, wherein the optical sensor is configured to sense light incident on the optical sensor, and wherein the travel speed sensing system is configured to determine a travel speed of the welding torch, a direction of the welding torch, or both, based on the sensed light, the optical sensor is configured to acquire images of a surface in a weld area, and the travel speed sensing system is configured to determine the travel speed of the welding torch based on the images; and

a positioning mechanism configured to maintain the optical sensor at a specific distance relative to the surface in the weld area across a range of angles of the welding torch relative to a workpiece, across a range of distances of the welding torch relative to the workpiece, or both.

19. The travel speed sensing system of claim 18, wherein the optical sensor comprises a range finding mechanism configured to determine a distance from the optical sensor to the surface, and wherein the travel speed sensing system is configured to determine the travel speed based on the distance.

20. The travel speed sensing system of claim 18, wherein the travel speed sensing system is configured to determine the travel speed using optical flow algorithms applied to the images acquired via the optical sensor.

21. The travel speed sensing system of claim 18, comprising:

an optical surface motion sensor having the optical sensor and a light source, wherein the optical surface motion sensor is configured to;

output light toward the surface in the weld area via the light source; and

sense light reflected from the surface via the optical sensor.

22. The travel speed sensing system of claim 18, comprising a sensor disposed on the welding torch, wherein the sensor is configured to sense a parameter indicative of an angle of the welding torch, and wherein the travel speed sensing system is configured to determine the travel speed based in part on the sensed parameter.