US 11,906,369 B2
Overheat detection with clamp health monitoring
Aswin Kumar Vallamkondu, Karnataka (IN); Mark Sherwood Miller, Lakeville, MN (US); and Stefan Coreth, Roanoke Rapids, NC (US)
Assigned to KIDDE TECHNOLOGIES, INC., Wilson, NC (US)
Filed by Kidde Technologies, Inc., Wilson, NC (US)
Filed on Nov. 18, 2021, as Appl. No. 17/529,868.
Claims priority of application No. 202111042968 (IN), filed on Sep. 22, 2021.
Prior Publication US 2023/0092269 A1, Mar. 23, 2023
Int. Cl. G01K 11/3206 (2021.01); B64D 45/00 (2006.01); G01K 1/14 (2021.01); G01H 9/00 (2006.01)
CPC G01K 11/3206 (2013.01) [B64D 45/00 (2013.01); G01H 9/004 (2013.01); B64D 2045/009 (2013.01); B64D 2045/0085 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A detection system in an aircraft comprising:
an optical fiber arranged along a structure of the aircraft and affixed to the structure with clamps that are spaced apart along the structure, wherein the optical fiber includes two or more sets of fiber Bragg gratings (FBGs);
a light source configured to generate light with two or more wavelengths for injection into the optical fiber; and
processing circuitry configured to identify an overheat condition and monitor vibration experienced by the optical fiber based on reflected signals generated by the two or more sets of FBGs, wherein integrity of the clamps is indicated by monitoring the vibration;
wherein each of the two or more FBGs of the optical fiber has a different grating pitch than others of the two or more FBGs and generates the reflected signals with a different reflected wavelength than the others of the two or more FBGs; and
wherein the overheat condition and the vibration cause a shift in the reflected wavelength of the reflected signals produced by affected ones of the two or more FBGs, the shift being periodic over a predefined duration when based on the vibration and the shift being non-periodic over the predefined duration when based on the overheat condition.