Patent FR-2996916-A1 (FR)
Title: Non-destructive testing the integrity of a composite material panel used e.g. as floor panel of an aircraft, by transmitting a predetermined wave of an electromagnetic excitation towards panel, and acquiring a frequency of response wave
Inventor: KERN XAVIER
IPC: G01N22/00
Filed: 2012-10-16
Abstract: The method comprises: transmitting a predetermined wave of an electromagnetic excitation (30) towards a composite material panel (10) comprising an electromagnetic element (16) configured to transmit an electromagnetic wave; acquiring a frequency of the response electromagnetic wave emitted from the electromagnetic element in response to the electromagnetic excitation; comparing a frequency of the acquired wave with a reference frequency; and detecting the damage of the panel if there is a difference between the acquired frequency of the response wave and the reference frequency. The method comprises: transmitting a predetermined wave of an electromagnetic excitation (30) towards a composite material panel (10) comprising an electromagnetic element (16) configured to transmit an electromagnetic wave; acquiring a frequency of the response electromagnetic wave emitted from the electromagnetic element in response to the electromagnetic excitation; comparing a frequency of the acquired response electromagnetic wave with a reference frequency; and detecting the damage of the panel if there is a difference between the acquired frequency of the response wave and the reference frequency. A panel structure (14) is composed of a set of layers. A parting plane (PS) is parallel to a fabrication plane which the layers are laid out. A normal direction is a direction perpendicular to the parting plane along which the layers are superimposed. The electromagnetic element is established through the layers parallel to the normal direction, or is laid out between the two layers parallel to the parting plane. The electromagnetic element is established in any dimension such as length, width or height, of the panel. An inspecting device (28) is used to emit the electromagnetic wave excitation to acquire the frequency of the response electromagnetic wave of the electromagnetic element. The electromagnetic inspecting device is transportable. The electromagnetic element is an inductive element having a shape of a wire. The electromagnetic element is a resonant circuit including the inductive element and a capacitive element. The electromagnetic element is a radio frequency identification (RFID) including an electronic chip associated with an antenna or a circuit including the inductive element and the capacitive element. A set of electromagnetic elements is assembled in an ordered manner in the structure of the panel. Each electromagnetic element has a standard specific frequency. The analysis of the various waves of the electromagnetic wave of the various electromagnetic elements is performed to know the state of each electromagnetic element and to precisely locate the damage of the structure of the panel. The standard frequency of each electromagnetic element is measured and recorded at the time of a stage of benchmarking carried out before the establishment of each electromagnetic element in the structure of the panel and/or carried out once the panel is set up in its environment.