Ultrasonic inspection system, ultrasonic inspection method and aircraft structural object

Patent metadata

Field	Value
Publication number	US-11226311-B2
Application number	US-201816149281-A
Country	US
Kind code	B2
Filing date	Oct 2, 2018
Priority date	Apr 6, 2016
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

According to one implementation, an ultrasonic inspection system includes: a first inspection unit, a second inspection unit, and a signal processing system. The first inspection unit acquires a detection signal of a first ultrasonic wave in a first inspection section of an structural object, using a first ultrasonic transducer and a first ultrasonic sensor. The second inspection unit acquires a detection signal of a second ultrasonic wave in a second inspection section of the structural object, using a second ultrasonic transducer and a second ultrasonic sensor. The signal processing system obtains an index value representing inspection information of at least one of the first inspection section and the second inspection section, based on the detection signal of the first ultrasonic wave and the detection signal of the second ultrasonic wave.

First claim

What is claimed is:

1. An ultrasonic inspection system comprising:
a first inspection unit that acquires a detection signal of a first ultrasonic wave in a first inspection section of a structural object, using a first ultrasonic transducer and a first ultrasonic sensor;
a second inspection unit that acquires a detection signal of a second ultrasonic wave in a second inspection section of the structural object using a second ultrasonic transducer and a second ultrasonic sensor; and
a signal processing circuit that obtains the detection signal of the first inspection unit and the detection signal of the second inspection unit and determines an index value representing inspection information of at least one of the first inspection section and the second inspection section, based on the detection signal of the first ultrasonic wave and the detection signal of the second ultrasonic wave, and wherein the index value determination by the signal processing circuit is limited to common thickness, width and material composition demarcated regions in the structural object, with the first and second inspection sections representing two of said demarcated regions, and wherein the index value determination by the signal processing circuit is based only on detection signals generated from commonly spaced apart, along an axis transverse to a direction of the width, pairs of ultrasonic transducers and sensors, with said first and second ultrasonic transducers and sensors representing two of said spaced apart pairs,
wherein the first and second inspection sections are plate form areas separated from each other by at least one wall surface of a stringer, a spar, a rib or a frame of the structural object, wherein the structural object is an aircraft structural object, and which at least one wall surface provides for demarcation into common width first and second inspection sections, and
wherein the index value is a cross correlation coefficient, a root mean square error, a representative value of a difference signal, or a representative value of a division signal between the detection signals or between signals corresponding to the detection signals, and
wherein the acquired detection signals of the first inspection unit and the second inspection unit include a first Lamb wave and a second Lamb wave, respectively, with an interval between the first ultrasonic transducer and the first ultrasonic sensor being the same as an interval between the second ultrasonic transducer and the second ultrasonic sensor, and each of the plate form areas of the first inspection section and the second inspection section being platy such that the first Lamb wave of the first inspection section and the second Lamb wave of the second inspection section pass through a common width and thickness platy section representing, respectively, the first and second inspection sections.

2. The ultrasonic inspection system according to claim 1 ,
wherein the signal processing circuit is adapted to obtain the index value without referring to any of a past detection signal of an ultrasonic wave in the first inspection section and a past detection signal of an ultrasonic wave in the second inspection section.

3. The ultrasonic inspection system according to claim 2 , further comprising:
a third inspection unit that acquires a detection signal of a third ultrasonic wave in a third inspection section of the structural object, using a third ultrasonic transducer and a third ultrasonic sensor, the third inspection section being another one of the demarcated regions;
wherein the signal processing circuit is adapted to obtain inspection information including the index value based on the detection signal of the first ultrasonic wave and the detection signal of the second ultrasonic wave, an index value based on the detection signal of the first ultrasonic wave and the detection signal of the third ultrasonic wave, and an index value based on the detection signal of the second ultrasonic wave and the detection signal of the third ultrasonic wave.

4. The ultrasonic inspection system according to claim 2 , comprising:
at least four inspection units including the inspection units, the at least four inspection units respectively acquiring detection signals in inspection sections disposed two-dimensionally,
wherein the signal processing circuit is adapted to obtain index values, each of the index values being based on two detection signals acquired by two inspection units selected out of the at least four inspection units, a number of the index values being at least a number of combinations for selecting the two inspection units from the at least four inspection units.

5. The ultrasonic inspection system according to claim 1 , further comprising:
a third inspection unit that acquires a detection signal of a third ultrasonic wave in a third inspection section of the structural object, using a third ultrasonic transducer and a third ultrasonic sensor, the third inspection section being another one of the demarcated regions;
wherein the signal processing circuit is adapted to obtain inspection information including the index value based on the detection signal of the first ultrasonic wave and the detection signal of the second ultrasonic wave, an index value based on the detection signal of the first ultrasonic wave and the detection signal of the third ultrasonic wave, and an index value based on the detection signal of the second ultrasonic wave and the detection signal of the third ultrasonic wave.

6. The ultrasonic inspection system according to claim 5 ,
wherein the signal processing circuit is adapted to automatically detect an inspection section, in which a defect exists or the defect may exist, by detecting a singular value from the index values.

7. The ultrasonic inspection system according to claim 5 , comprising:
at least four inspection units including the first and second inspection units, the at least four inspection units respectively acquiring detection signals in inspection sections disposed two-dimensionally,
wherein the signal processing circuit is adapted to obtain index values, each of the index values being based on two detection signals acquired by two inspection units selected out of the at least four inspection units, a number of the index values being at least a number of combinations for selecting the two inspection units from the at least four inspection units.

8. The ultrasonic inspection system according to claim 1 , comprising:
at least four inspection units including the first and second inspection units, the at least four inspection units respectively acquiring detection signals in inspection sections disposed two-dimensionally,
wherein the signal processing circuit is adapted to obtain index values, each of the index values being based on two detection signals acquired by two inspection units selected out of the at least four inspection units, a number of the index values being at least a number of combinations for selecting the two inspection units from the at least four inspection units.

9. The ultrasonic inspection system according to claim 1 ,
wherein the signal processing circuit is adapted to automatically detect an inspection section, in which a defect exists or the defect may exist, out of the first inspection section and the second inspection section, based on a temporal change of the index value.

10. An aircraft including the ultrasonic inspection system according to claim 1 as a part.

11. The ultrasonic inspection system according to claim 1 , wherein said first ultrasonic transducer limits ultrasonic wave output to the direction of travel that is parallel with the direction of elongation of the at least one

Assignees

• Subaru Corp

Inventors

• Soejima Hideki

Classifications

• G01N2291/0258

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

• G01N2291/106

  one or more transducer arrays · CPC title

• G01N2291/0289

  Internal structure, e.g. defects, grain size, texture · CPC title

• G01N29/48 Primary

  by amplitude comparison · CPC title

• G01N2291/2694

  Wings or other aircraft parts · CPC title