Alenia Aermacchi S.p.a.

Alenia Aeronautica S.p.a.

Leonardo Corporation

Michele Iannone

Generoso Iannuzzo

Giovanni Sagnella

Alfonso Apicella

Giampiero Coppola

A method for performing diagnostics of a structure subject to loads, in particular an aircraft structure, is described, said method being implemented by means of an arrangement of sensors located at relevant points of the structure and corresponding neural networks, and comprising: training the neural network in order to establish an associative relationship between the local displacement of the structure in a subset of relevant points and the local displacement of the structure in at least one residual relevant point; detecting the local displacement of the structure in a plurality of relevant points under operating conditions; estimating the local displacement of the structure in at least one residual relevant point by means of the associated neural network on the basis of the pre-established associated relationship; and comparing the local displacement of the estimated structure with the detected local displacement at the residual relevant point.

Method for performing diagnostics of a structure subject to loads based on the measurement of displacements and system for implementing said method

A method for manufacturing a composite part includes preparing a stack of plies made of a starting material, applying a vacuum bag to the stack of plies, and subjecting the stack of plies to a temperature and pressure cycle in an autoclave. The starting material is a laminate material of resin matrix reinforced with a fiber material. The matrix has a core layer of semi-crystalline thermoplastic resin and a pair of outer layers of amorphous thermoplastic resin arranged on opposite sides of the core layer. The glass transition temperature of the amorphous thermoplastic resin is below the melting point of the semi-crystalline thermoplastic resin. The autoclave temperature cycle heating rapidly the stack of plies to a working temperature above the transition temperature, but below the melting point, keeping the stack of plies at the working temperature during a time period for compaction alone; and cooling the stack of plies.

Method for manufacturing a composite part from a preimpregnated material with a semi-crystalline matrix having an amorphous surface layer

A method for performing diagnostics of a structure subject to loads, in particular an aircraft structure, is implemented by an arrangement of sensors located at relevant points of the structure and corresponding neural networks. The method includes training the neural network in order to establish an associative relationship between the state of the structure in a subset of relevant points and the state of the structure in at least one residual relevant point. The state of the structure is detected in a plurality of relevant points under operating conditions. The state of the structure is estimated in at least one residual relevant point by the associated neural network on the basis of the pre-established associated relationship. The state of the estimated structure is compared with the detected state at the residual relevant point, such that an intact state of the structure is determined if the expected and detected values of the state parameter match, or a defective state of the structure is determined if these values differ.

Method for performing diagnostics of a structure subject to loads and system for implementing said method

Systems are provided for measuring absorbed humidity in a composite material, including an item of composite material which includes a plurality of plies of material consolidated through the action of pressure and heat, wherein each ply of material is formed from a resin matrix reinforced with a fiber material, an insert embedded in the composite material, which is positioned in an interface zone between a first and a second ply of material, and in which at least one cavity is formed, in fluid communication with first and second ply of material, and an ambient humidity sensor positioned inside the cavity, capable of providing a signal indicating the humidity content in the atmosphere present inside the cavity. Corresponding methods are also provided.

Systems and methods for measuring absorbed humidity in a composite material

A method for prognostics of a structure subject to loads, particularly an aircraft structure, includes, detecting the state (strains) of the structure at multiple primary points and additional points. The loads acting on the structure associated with the state detected in the primary points are determined. Based on the determined loads, the state of the structure in the additional points is estimated. The estimated state of the structure is compared with the state detected in the additional points. A soundness state of the structure is assessed if the estimated and detected values of the state quantity are in agreement, or a defectiveness state of the structure if such values differ.

Procedure for the prognostic of a structure subject to loads

An article of composite material includes a plurality of plies of material consolidated through the application of pressure and heating, in which each material ply is made by a resin matrix reinforced with fiber material. The article includes heating electrical resistance and temperature sensing devices embedded in the composite material, which are respectively placed in at least one interface zone between the material plies and are suitable to allow a temperature control of the article in service.

Growing community of inventors

Torre Annunziata, Italy

Michele Iannone