System and method for workpiece measurement during forging by image processing
View Patent ↗The amount of elongation of a workpiece during forging can be determined by image processing to calculate the total amount of horizontal movement of marked patterns such as forging scale on the ends of the workpiece which move away from a forging bite during the forging blow. Images of marked patterns before and after a forging blow on both sides of the bite of a forging die are compared to determine the movement of the marked patterns and thus the movement of the ends of the workpiece. A method and system of determining the elongation and vertical displacement of a workpiece during forging is disclosed.
1. A method for elongation measurement of a workpiece during forging comprising:
acquiring a first image of a first scanned area having a first mark pattern on a side of the workpiece between a distal end of a first end of the workpiece and a prospective forging location before a forging blow;
acquiring a second image of a second scanned area having a second mark pattern on a side of the workpiece between a distal end of a second end of the workpiece and the prospective forging location before the forging blow;
acquiring a third image of a third scanned area including at least a portion of the first scanned area having the first mark pattern on the side of the workpiece between the distal end of the first end of the workpiece and a forging location after the forging blow;
acquiring a fourth image of a fourth scanned area including at least a portion of the second scanned area having the second mark pattern on the side of the workpiece between the distal end of the second end of the workpiece and the forging location after the forging blow;
determining a relative horizontal movement of the first end of the workpiece by correlating a horizontal position of the first mark pattern in the first image relative to a horizontal position of the first mark pattern in the third image;
determining a relative horizontal movement of the second end of the workpiece by correlating a horizontal position of the second mark pattern in the second image relative to a horizontal position of the second mark pattern in the fourth image; and
calculating an elongation of the workpiece wherein the elongation of the workpiece is a sum of the relative horizontal movement of the first end of the workpiece and the relative horizontal movement of the second end of the workpiece.
2. The method for elongation measurement of a workpiece during forging of claim 1 wherein the third scanned area includes the entire first scanned area having the first mark pattern and the fourth scanned area includes the entire second scanned area having the second mark pattern.
3. The method for elongation measurement of a workpiece during forging of claim 1 further comprising the steps of:
determining a relative vertical movement of the first end of the workpiece by correlating a vertical position of the first mark pattern in the first image relative to a vertical position of first mark pattern in the third image;
determining a relative vertical movement of the second end of the workpiece by correlating a vertical position of the second mark pattern in the second image relative to a vertical position of the second mark pattern in the fourth image.
4. The method for elongation measurement of a workpiece during forging of claim 3 wherein the third scanned area includes the entire first scanned area having the first mark pattern and the fourth scanned area includes the entire second scanned area having the second mark pattern.
5. The method for elongation measurement of a workpiece during forging of claim 1 further comprising:
determining a distance to the side of the workpiece having the first mark pattern and the second mark pattern, wherein calculating the elongation of the workpiece is based on the determination of the distance to the side of the workpiece having the first mark pattern and the second mark pattern.
6. The method for elongation measurement of a workpiece during forging of claim 3 further comprising the steps of:
determining a distance to the side of the workpiece having the first mark pattern and the second mark pattern, wherein calculating the elongation of the workpiece is based on the determination of the distance to the side of the workpiece having the first mark pattern and second mark pattern;
determining the relative vertical movement of the first end of the workpiece based on the determination of the distance to the side of the workpiece having the first mark pattern and second mark pattern; and
determining the relative vertical movement of the second end of the workpiece based on the determination of the distance to the side of the workpiece having the first mark pattern and second mark pattern.
7. The method for elongation measurement of a workpiece during forging of claim 1 further comprising the steps of:
determining a position and a size of the first scanned area and the second scanned area based on a workpiece height prior to acquiring the first image of the first scanned area and the second image of the second scanned area.
8. A method for elongation measurement of a workpiece during forging comprising:
acquiring a first image of a first scanned area having a first mark pattern on a side of the workpiece between a distal end of a first end of the workpiece and a prospective forging location before a forging blow;
acquiring a second image of a second scanned area having a second mark pattern on a side of the workpiece between a distal end of a second end of the workpiece and a prospective forging location before the forging blow;
acquiring a third image of a third scanned area including at least a portion of the first scanned area having the first mark pattern on a side of the workpiece between the distal end of the first end of the workpiece and a forging location during the forging blow;
acquiring a fourth image of a fourth scanned area including at least a portion of the second scanned area having a second mark pattern on a side of the workpiece between a distal end of the second end of the workpiece and a forging location during the forging blow;
determining the relative horizontal movement of the first end of the workpiece during the forging blow by correlating the horizontal position of the first mark pattern in the first image relative to the horizontal position of first mark pattern in the third image;
determining the relative horizontal movement of the second end of the workpiece during the forging blow by correlating the horizontal position of the second mark pattern in the second image relative to the horizontal position of the second mark pattern in the fourth image; and
calculating the elongation of the workpiece during the forging blow wherein the elongation of the workpiece is the sum of the relative horizontal movement of the first end of the workpiece and the relative horizontal movement of the second end of the workpiece.
9. The method for elongation measurement of a workpiece during forging according to claim 8 further comprising the steps of:
determining the relative vertical movement of the first end of the workpiece during the forging blow by correlating the vertical position of the first mark pattern in the first image relative to the vertical position of first mark pattern in the third image;
determining the relative vertical movement of the second end of the workpiece during the forging blow by correlating the vertical position of the second mark pattern in the second image relative to the vertical position of the second mark pattern in the fourth image.
10. The method for elongation measurement of a workpiece during forging according to claim 9 further comprising the steps of:
acquiring a fifth image of a fifth scanned area including at least a portion of the first scanned area having the first mark pattern on a side of the workpiece between the distal end of the first end of the workpiece and the forging location during the forging blow;
acquiring a sixth image of a sixth scanned area including at least a portion of the second scanned area having a second mark pattern on a side of the workpiece between the distal end of the second end of the workpiece and the forging location during the forging blow;
determining the relative horizontal movement of the first end of the workpiece between the acquiring of the third image and the acquiring of the fifth image during the forging blow by correlating the horizontal position of the first mark pattern in the third image relative to the horizontal position of first mark pattern in the fifth image;
determining the relative horizontal movement of the second end of the workpiece during the forging blow by correlating the horizontal position of the second mark pattern in the fourth image relative to the horizontal position of the second mark pattern in the sixth image; and
calculating the elongation of the workpiece from the acquiring of the third image and fourth image to the acquiring of the fifth image and sixth image during the forging blow wherein the elongation of the workpiece is the sum of the relative horizontal movement of the first end of the workpiece and the relative horizontal movement of the second end of the workpiece from the acquiring of the third image and fourth image to the acquiring of the fifth image and sixth image; and
determining the relative vertical movement of the first end of the workpiece during the forging blow by correlating the vertical position of the first mark pattern in the third image relative to the vertical position of first mark pattern in the fifth image;
determining the relative vertical movement of the second end of the workpiece during the forging blow by correlating the vertical position of the second mark pattern in the fourth image relative to the vertical position of the second mark pattern in the sixth image.
11. A system for elongation measurement of a workpiece during forging comprising:
a means for:
a) acquiring a first image of a first scanned area having a first mark pattern on a side of the workpiece between a distal end of a first end of the workpiece and a prospective forging location before a forging blow;
b) acquiring a second image of a second scanned area having a second mark pattern on a side of the workpiece between a distal end of a second end of the workpiece and the prospective forging location before the forging blow;
c) acquiring a third image of a third scanned area including at least a portion of the first scanned area having the first mark pattern on the side of the workpiece between the distal end of the first end of the workpiece and a forging location after the forging blow;
d) acquiring a fourth image of a fourth scanned area including at least a portion of the second scanned area having the second mark pattern on the side of the workpiece between the distal end of the second end of the workpiece and the forging location after the forging blow;
a means for determining a relative horizontal movement of the first end of the workpiece by correlating a horizontal position of the first mark pattern in the first image relative to a horizontal position of the first mark pattern in the third image and determining a relative horizontal movement of the second end of the workpiece by correlating a horizontal position of the second mark pattern in the second image relative to a horizontal position of the second mark pattern in the fourth image; and for calculating an elongation of the workpiece wherein the elongation of the workpiece is a sum of the relative horizontal movement of the first end of the workpiece and the relative horizontal movement of the second end of the workpiece.
12. The system for elongation measurement of a workpiece during forging of claim 11 further comprising:
a means for:
determining a relative vertical movement of the first end of the workpiece by correlating a vertical position of the first mark pattern in the first image relative to a vertical position of the first mark pattern in the third image; and
determining a relative vertical movement of the second end of the workpiece by correlating a vertical position of the second mark pattern in the second image relative to a vertical position of the second mark pattern in the fourth image.
13. The system for elongation measurement of a workpiece during forging of claim 11 further comprising:
a means for determining a position and a size of the first scanned area and the second scanned area based on a workpiece height prior to acquiring the first image of the first scanned area and the second image of the second scanned area.
14. The method for elongation measurement of a workpiece during forging of claim 1 wherein determining the relative horizontal movement of the first end of the workpiece includes determining a length value that corresponds to a maximum correlation on a response curve that correlates image data of the first scanned area with that of the third scanned area, and determining the relative horizontal movement of the second end of the workpiece includes determining a length value that corresponds to a maximum correlation on a response curve that correlates image data of the second scanned area with that of the fourth scanned area.
15. The system for elongation measurement of a workpiece during forging of claim 11 wherein the means for determining the relative horizontal movement of the first end of the workpiece and the relative horizontal movement of the second end of the workpiece, determines a length value that corresponds to a maximum correlation on a response curve that correlates image data of the first scanned area with that of the third scanned area, and determines a length value that corresponds to a maximum correlation on a response curve that correlates image data of the second scanned area with that of the fourth scanned area.