Instrumented PCB for predictive maintenance
The manufacturing of electronic equipment, and more specifically Printed Circuit Boards (PCBs), represents a significant share of the environmental impact of digital technologies, which must be minimized. Within a circular economy approach, the development of monitoring and diagnostic tools for assessing the health status of these boards could feed into the product’s digital passport and facilitate their reuse in a second life. In a preventive and prescriptive maintenance perspective, such tools could extend their lifespan by avoiding unnecessary periodic replacement in applications where reliability is a priority, as well as adapting their usage to prevent premature deterioration.
This PhD proposes to explore innovative instrumentation of PCBs using ‘virtual’ sensors, advanced estimators powered by measurement modalities (such as piezoelectric, ultrasonic, etc.) that could be integrated directly within the PCBs. The objective is to develop methods for monitoring the health status of the boards, both mechanically (fatigue, stresses, deformations) and electronically.
A first step will consist of conducting a state-of-the-art review and simulations to select the relevant sensors, define the quantities to be measured, and optimize their placement. Multi-physics modeling and model reduction will then make it possible to link the data to PCB integrity indicators characterizing its health status. The approach will combine numerical modeling, experimental validations, and multiparametric optimization methods.
Optically Pumped Magnetometers based on helium-3
The laboratory, reknown for its expertise in high-resolution and high-precision magnetic measurements, has been developing and providing for several decades successive generations of optically pumped helium-4 magnetometers. These instruments serve as reference sensors aboard the ESA Swarm mission satellites launched in late 2013, and will also equip the forthcoming NanoMagSat mission, scheduled to launch from the end of 2027 onward.
In an effort to diversify its activities and to address emerging applications involving autonomous or “deploy-and-forget” sensors, where power consumption constraints are particularly demanding, the laboratory now aims to develop a new magnetometer technology based on helium-3 atoms as the sensitive medium. The lifetime of the helium-3 atomic state used for magnetic field measurement is significantly longer than that of the equivalent helium-4 state. This property enables a substantial reduction in optical pumping requirements, thereby offering the prospect of improved energy efficiency and power consumption.
The objective of this research is to advance the Technology Readiness Level (TRL) of this helium-3-based magnetometer architecture, with the ultimate goal of realizing an instrument that combines outstanding metrological performance with exceptional energy frugality, suited to these highly specific and constrained applications.
Accordingly, the purpose of this PhD work will be to design, implement, and experimentally evaluate a helium-3 magnetometer architecture capable of fulfilling these performance and efficiency objectives.