1. Field
The present disclosure relates generally to non-destructive inspection and, in particular, to performing non-destructive inspection on a structure. Still more particularly, the present disclosure relates to a method and apparatus for detecting inconsistencies in a structure using a plurality of types of ultrasonic signals substantially simultaneously.
2. Background
In manufacturing aircraft, vehicles, and other structures, inspection of parts used to form these structures is often performed to determine whether the parts will have desired parameters for a desired performance of the part. Additionally, the structures and parts are inspected as part of normal maintenance when the aircraft, vehicles, and other structures are in use.
Non-destructive testing is commonly performed on these parts. Non-destructive testing is used to evaluate the properties of a part without altering the ability to use the part in service.
Ultrasound testing is a type of non-destructive testing. Ultrasound testing is often used to perform inspections on aircraft parts that include, or are comprised of, composite materials. Ultrasound testing involves transmitting acoustic waves through a test object, such as an aircraft part or structure.
Ultrasound testing is commonly performed using a transducer. The transducer is configured to send acoustic waves into a test object at a near side and detect a response to the acoustic waves. The response to these acoustic waves is analyzed to determine whether inconsistencies are present in the test object.
Different types of inconsistencies may be identified using different types of acoustic waves. For example, inconsistencies on a far side of a structure may be identified using shear waves. A far side of the structure is a side of the structure opposite the near side into which the acoustic waves are transmitted. As another example, inconsistencies on a near side of the structure may be identified using surface waves. In conventional ultrasonic inspection, each type of acoustic wave may be detected on a separate pass of the structure. For example, a first pass of the structure may detect surface waves while a second pass of the structure may detect shear waves. However, performing multiple inspection passes of the structure may use an undesirable amount of time, energy, or resources. Therefore, it would be desirable to have a method and apparatus that take into account at least some of the issues discussed above, as well as other possible issues.