Infrared detection of defects in wind turbine blades
AssigneeKurion, Inc.
InventorsJoseph W. Maresca, Jr., Wesley L. Bratton, Wilhelmina C. Leuschen, David A. Rohrig
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Abstract
A method and an apparatus for detecting defects in the composite materials of a wind turbine blade or similar type of structure using an infrared (IR) camera. The temperature of the wind turbine blade is changed in such a way as to produce IR intensity changes in the region of the defect that can be visually detected or detected using a computer and signal processing algorithms. The same approach will work on other composite structures such as those found on aircraft.
Claims44
A method for detection of composite defects in wind turbine blades including a composite using IR images of the surface of the composite comprising the steps of:
- a. while the wind turbine blade is not in use, cooling a surface of the wind turbine blade located on an inside region of the blade;
- b. collecting an IR intensity image of the surface of the blade with an IR camera, while the wind turbine blade is statutory;
- and
- c. detecting defects in the composite on the surface of the wind turbine blade by identifying areas of the composite that are warmer or cooler than the surrounding background, where a background of the wind turbine blade not containing any defects is determined using a median filter as applied to the IR image to determine the background of the wind turbine blade at each pixel in the image, and where false regions that may occur at the corners of an IR image due to the median filter are identified as false defects because the size of the region of the IR image of the wind turbine blade grows as the size of the median filter increases.
A method for detection of composite defects in wind turbine blades including a composite using IR images of the surface of the composite comprising the steps of:
- a. while the wind turbine blade is not in use, cooling a surface of the wind turbine blade located on an inside region of the blade, where the inside region of the blade is cooled by blowing a fluid through an inside region of the wind turbine blade;
- b. collecting an IR intensity image of the surface of the blade with an IR camera, while the wind turbine blade is statutory;
- and
- c. detecting defects in the composite on the surface of the wind turbine blade by identifying areas of the composite that are warmer or cooler than the surrounding background, where the inside region is cooled by blowing a fluid through an inside region of the wind turbine blade, where a background of the wind turbine blade not containing any defects is determined using a median filter as applied to the IR image to determine the background of the wind turbine blade at each pixel in the image, and where false regions that may occur at the corners of an IR image due to the median filter are identified as false defects because the size of the region of the IR image of the wind turbine blade grows as the size of the median filter increases.
A method for detection of composite defects in wind turbine blades using IR images of the surface of said composite comprising the steps of:
- a. changing the temperature of the surface of the wind turbine blade conductively;
- b. collecting an IR intensity image of the surface of the said blade with an IR camera;
- c. identifying the area in the image produced by said defect that is warmer or cooler than the surrounding background, where the background of the wind turbine blade not containing any defects is determined using a median filter as applied to the IR image to determine the background of the wind turbine blade at each pixel in the image, and where false regions that may occur at the corners of an IR image due to the median filter are identified as false defects because the size of the region of the IR image of the wind turbine blade grows as the size of the median filter increases.
A method for detection of composite defects in wind turbine blades including a composite using IR images of the surface of the composite comprising the steps of:
- a. while the wind turbine blade is not in use, cooling a surface of the wind turbine blade located on an inside region of the blade;
- b. collecting an IR intensity image of the surface of the blade with an IR camera, while the wind turbine blade is statutory;
- and
- c. detecting defects in the composite on the surface of the wind turbine blade by identifying areas of the composite that are warmer or cooler than the surrounding background, and where the IR image obtained from said IR camera and any defects identified in said IR image can be located with respect to a physical location on the wind blade composite being inspected by identifying fiducials located on said wind blade in the IR image and based on the known pattern and location of these fiducials, transforming the coordinates of said IR image and said fiducials from the image to a coordinate system on said wind blade.
A method for detection of composite defects in wind turbine blades including a composite using IR images of the surface of the composite comprising the steps of:
- a. while the wind turbine blade is not in use, cooling a surface of the wind turbine blade located on an inside region of the blade;
- b. collecting an IR intensity image of the surface of the blade with an IR camera, while the wind turbine blade is statutory;
- and
- c. detecting defects in the composite on the surface of the wind turbine blade by identifying areas of the composite that are warmer or cooler than the surrounding background, where the inside region is cooled by blowing a fluid through an inside region of the wind turbine blade, and where the IR image obtained from said IR camera and any defects identified in said IR image can be located with respect to a physical location on the wind blade composite being inspected by identifying fiducials located on said wind blade in the IR image and based on the known pattern and location of these fiducials, transforming the coordinates of said IR image and said fiducials from the image to a coordinate system on said wind blade.
Dependencies are inferred from the claim text.