US 12,435,642 B2
Optical in-situ inspection system
Jeremiah C. Lee, Coventry, CT (US); David L. Lincoln, Cromwell, CT (US); Scott Goyette, Moosup, CT (US); Zaffir A. Chaudhry, Portland, CT (US); and Danbing Seto, Avon, CT (US)
Assigned to RTX Corporation, Farmington, CT (US)
Filed by RTX Corporation, Farmington, CT (US)
Filed on Aug. 25, 2023, as Appl. No. 18/238,065.
Prior Publication US 2025/0067194 A1, Feb. 27, 2025
Int. Cl. F01D 21/00 (2006.01); G01N 21/88 (2006.01); G01P 3/38 (2006.01)
CPC F01D 21/003 (2013.01) [G01N 21/88 (2013.01); G01P 3/38 (2013.01); F05D 2220/32 (2013.01); F05D 2260/10 (2013.01); F05D 2260/80 (2013.01); G01N 2291/2693 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for in-situ inspection of a gas turbine engine fan, comprising:
positioning a sensor to capture images of a surface of at least one gas turbine engine fan blade;
coupling a processor to the sensor, the processor configured to determine damage to the at least one gas turbine engine fan blade based on image analytics; wherein the processor performs operations comprising:
receiving, by the processor, imaging data for the surface of the at least one gas turbine engine fan blade from the sensor;
determining, by the processor, a rotational speed of the fan; and
determining, by the processor, a fan synchronization;
recording a segment of footage to perform a principal component analysis;
performing the principal component analysis to create a list of dominant modes of a series of footage in the segment;
projecting all the footage in the segment onto a leading order mode; and
providing a frequency modulated sinusoidal time variation of coefficients plot, wherein each point on the plot of coefficients corresponds to a particular frame of the blade appearing in front of the sensor.