Located on the Saclay plateau in the Paris area, CEA LIST is a technology research institute for software-intensive systems. In the field of non-destructive testing (NDT), CEA LIST research focuses on simulation, data processing and the design of innovative instrumentation and sensors. Studies focus mainly on ultrasonic, electromagnetic (eddy current) and X-ray techniques. In this context, LIST is developing the CIVA platform (https://list.cea.fr/en/page/civa-simulation-and-analysis-software-for-non-destructive-testing-ndt/), an NDT simulation software based on research carried out by the DIN department.

Structural Health Monitoring (SHM) can be defined as a process of implementing a nondestructive damage identification strategy for engineering infrastructures, such as an aircraft, pipeline or nuclear power plant, usually by permanently installing a network of sensors. SHM systems can detect the occurrence and/or monitor the progression of defects (corrosion, delamination, etc.) with continuous monitoring. One physical phenomenon that enables defects to be detected is the use of ultrasonic guided elastic waves propagating through the structure, emitted and detected by thin piezoelectric sensors or fiber optic sensors permanently attached to the structures – either embedded in the material or bonded to its surface. Usually, guided wave signals are analyzed in comparison to their previous state (baseline measurements) to detect defects. The advanced imaging algorithms such as delay and sum and RAPID applied to guided wave signals can help determining the location of the anomalies.

Remaining Useful Life (RUL) is an engineering tool designed to enable condition-based maintenance of systems and prevent their catastrophic failure. It can be based on comprehensive physical degradation models of the monitored systems, statistical models based on available data from similar systems, or a combination of both. Most of the academic research in this area is focused on the dynamic behavior of industrial machinery, and the use of ultrasonic guided waves still needs to be investigated further.

The aim of this internship is to investigate model based, physics based and hybrid RUL estimation techniques on the available ultrasonic guided wave data which will be processed using digital signal processing and imaging algorithms. It is planned to use a numerical on database of a crack growth in metallic structure and/or delamination growth in a plate made of composite materials.

Candidates must have at least two of the following skills to successfully complete this internship:

-        computer skills (Python);

-        knowledge of acoustics, wave propagation;

-        knowledge of signal processing;

-        knowledge of statistics;

-        an experience in academic bibliographical research.

This internship lasts 6 months. The trainee will receive a gross monthly stipend that will vary according to the level of their education. Trainees may also take advantage of CEA transport facilities. English speaking is mandatory.