In-flight damage detection system and damage detection method

Patent metadata

Field	Value
Publication number	US-11084601-B2
Application number	US-201816218097-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Sep 26, 2016
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

According to one implementation, a damage detection system includes: a physical quantity detection unit, a flight condition changing part and a damage detection part. The physical quantity detection unit detects a physical quantity of a structural object composing an aircraft during a flight of the aircraft. The flight condition changing part changes at least one flight condition of the aircraft to at least one specific flight condition when the physical quantity of the structural object has been detected by the physical quantity detection unit. The damage detection part determines whether a damage arose in the structural object, based on a physical quantity which has been detected, from the structural object of the aircraft flying with the at least one specific flight condition, by the physical quantity detection unit.

First claim

What is claimed is:

1. A damage detection system comprising:
a storage that stores:
instructions for flying an aircraft in an active damage detection flight mode that causes physical changes to the aircraft to facilitate detection of suspected damage, and
a plurality of reference physical quantities associated with the active damage detection flight mode and a structural object of the aircraft,
wherein the plurality of reference physical quantities include at least one of a strain, a vibration, or an acceleration of the structural object that is expected when the aircraft is in flight, in the active damage detection flight mode, without damage to the structural object;

a physical quantity detection unit, including at least one sensor, configured to detect a value of a first physical quantity of the structural object during a flight of the aircraft in a passive damage detection mode in which the physical quantity detection unit is operating during normal flight operations;
a flight condition changing circuit configured to change the flight of the aircraft to the active damage detection mode, to determine whether a damage arose in the structural object, when the value of the first physical quantity detected by the physical quantity detection unit indicates that the damage may have occurred in the structural object;
a damage detection circuit configured to determine whether the damage arose in the structural object, based on an additional value of the first physical quantity or a value of a second physical quantity of the structural object detected by the physical quantity detection unit while the aircraft is flying in the active damage detection flight mode; and
wherein the damage detection circuit is adapted to determine whether the damage arose in the structural object, based on a comparison of the additional value of the first physical quantity or the value of the second physical quantity with a corresponding one of the plurality of reference physical quantities for the active damage detection flight mode without damage to the structural object.

2. The damage detection system according to claim 1 ,
wherein the flight condition changing circuit is adapted to instruct a pilot of the aircraft to change the flight of the aircraft to the active damage detection mode manually by the pilot.

3. The damage detection system according to claim 1 ,
wherein the flight condition changing circuit is adapted to automatically change the flight of the aircraft to the active damage detection mode, by controlling a flight control system of the aircraft.

4. The damage detection system according to claim 1 ,
wherein the physical quantity detection unit includes:
an ultrasonic oscillator that makes the structural object propagate at least one ultrasonic wave;
an ultrasonic sensor that receives the at least one ultrasonic wave propagated by the structural object; and
a strain detection circuit that detects at least one strain quantity of the structural object based on a change of a waveform of the at least one ultrasonic wave, received by the ultrasonic sensor, from a reference waveform.

5. The damage detection system according to claim 1 ,
wherein the physical quantity detection unit includes:
a strain sensor that detects a strain which arose in the structural object; and
a strain detection circuit that detects a strain quantity of the structural object based on a detection signal from the strain sensor.

6. The damage detection system according to claim 1 ,
wherein the active damage detection mode corresponds to a specific flight condition for at least one of a load factor, an airspeed, and an angular velocity of the aircraft.

7. The damage detection system according to claim 1 , wherein the additional value of the first physical quantity or the value of the second physical quantity include at least one of a temperature acquired from a temperature sensor installed to the aircraft, an acceleration acquired from an acceleration sensor installed to the aircraft, and a strain quantity acquired from a strain gauge installed to the aircraft.

8. A damage detection system comprising:
a physical quantity detection unit configured to detect a value of a first physical quantity of a structural object composing an aircraft during a flight of the aircraft in a passive damage detection mode in which the physical quantity detection unit is active during normal flight operations;
a flight condition changing circuit configured to change the flight of the aircraft to an active damage detection mode that causes physical changes to the aircraft that facilitate a determination of whether a damage arose in the structural object, when the value of the first physical quantity detected by the physical quantity detection unit indicates that the damage may have occurred in the structural object; and
a damage detection circuit configured to determine whether the damage arose in the structural object, based on an additional value of the first physical quantity or a value of a second physical quantity of the structural object detected by the physical quantity detection unit while the aircraft is flying in the active damage detection mode;
wherein the physical quantity detection unit includes:
an ultrasonic oscillator that makes the structural object propagate at least one ultrasonic wave;
an ultrasonic sensor that receives the at least one ultrasonic wave propagated by the structural object;
a strain detection circuit that detects at least one strain quantity of the structural object based on a change of a waveform of the at least one ultrasonic wave, received by the ultrasonic sensor, from a reference waveform; and
an ultrasonic control circuit that changes at least one of a frequency and an amplitude of the at least one ultrasonic wave oscillated from the ultrasonic oscillator during the flight of the aircraft in the active damage detection mode,
wherein the additional value of the first physical quantity or the value of the second physical quantity is a strain quantity detected based on changes of waveforms of ultrasonic waves from reference waveforms, the ultrasonic waves being each oscillated from the ultrasonic oscillator with changing at least one of the frequency and the amplitude, the ultrasonic waves being each propagated by the structural object.

9. The damage detection system according to claim 8 ,
wherein the flight condition changing circuit is adapted to instruct a pilot of the aircraft to change the flight of the aircraft to the active damage detection mode manually by the pilot.

10. The damage detection system according to claim 8 ,
wherein the flight condition changing circuit is adapted to automatically change the flight of the aircraft to the active damage detection mode, by controlling a flight control system of the aircraft.

11. The damage detection system according to claim 8 ,
wherein the active damage detection mode of the aircraft is a flight mode with a specific value of at least one of a load factor, an airspeed, and an angular velocity of the aircraft.

12. A damage detection system comprising:
a physical quantity detection unit, including at least one sensor, configured to detect a value of a first physical quantity of a structural object composing an aircraft during a flight of the aircraft in a passive damage detection mode in which the physical quantity detection unit is active during normal flight operations;
a flight condition changing circuit configured to change the flight of the aircraft to an active damage detection flight mode that causes physical changes to the aircraft that facilitate a determination of whether a damage arose in the structural obje

Assignees

• Subaru Corp

Inventors

• Abe Masakatsu
• Soejima Hideki
• Fukurose Takeshi

Classifications

• G01N2291/2694

  Wings or other aircraft parts · CPC title

• G01N2291/0258

  Structural degradation, e.g. fatigue of composites, ageing of oils · CPC title

• G01M11/085

  the optical fiber being on or near the surface of the DUT · CPC title

• B64D2045/0085

  Devices for aircraft health monitoring, e.g. monitoring flutter or vibration · CPC title

• G01N29/4436

  with a reference signal (amplitude comparison G01N29/48) · CPC title