Agnese Staffa

Recent innovations in thermoplastic extrusion 3D printing have promoted the development of functional materials, such as conductive composites, which lead the way to the creation of sensors embedded directly into printed structures. To this aim, this paper presents a feasibility study on the use of a commercial conductive PLA filament for the realization of a 3D-printed temperature sensor integrated into a thermoplastic structure. To this end, a series of experiments were conducted on 3D-printed samples to analyse the correlation between electrical resistance and temperatures. The results obtained show a clear and reproducible relationship between the two quantities, from which a useful function was derived to estimate the temperature from the resistance measurement. This study confirms the potential of conductive PLA as a low-cost and customisable solution for thermal monitoring and represents a step forward towards the integration of functional sensors through additive manufacturing.

The progress in the development of sensors made using additive manufacturing (AM) techniques has opened up new possibilities for their integration into more complex structures, such as CubeSats. In this study, preliminary tests were conducted on printed sensors by FDM embedded in simple structures to evaluate their feasibility under simulated operational conditions, including temperature variations and dynamic loads. The results obtained represent a preliminary step toward the full integration of embedded sensors in 3D-printed structures. With further development, 3D-printed embedded sensors could be used to monitor dynamic loads and vibrations during service, which is essential for structural health monitoring and determining fatigue life.

Physics research is constantly pursuing more efficient silicon detectors, often trying to develop complex and optimized geometries, thus leading to non-trivial engineering challenges. Although critical for this optimization, there are few silicon tile mechanical data available in the literature. In an attempt to partially fill this gap, the present work details various mechanical-related aspects of spaceborne silicon detectors. Specifically, this study concerns three experimental campaigns with different objectives: a mechanical characterization of the material constituting the detector (in terms of density, elastic, and failure properties), an analysis of the adhesive effect on the loads, and a wirebond vibrational endurance campaign performed on three different unpotted samples. By collecting and discussing the experimental results, this work aims to fulfill its purpose of providing insight into the mechanical problems associated with this specific application and procuring input data of paramount importance. For the study to be complete, the perspective taken is broader than mere silicon analysis and embraces all related aspects; i.e., the detector–structure adhesive interface and the structural integrity of wirebonds. In summary, this paper presents experimental data on the material properties of silicon detectors, the impact of the adhesive on the gluing stiffness, and unpotted wirebond vibrational endurance. At the same time, the discussion of the results furnishes an all-encompassing view of the design-associated criticalities in experiments where silicon detectors are employed.

This paper presents the development and validation of a low-cost device for real-time detection of fatigue damage of structures subjected to vibrations. The device consists of an hardware and signal processing algorithm to detect and monitor variations in the structural response due to damage accumulation. The effectiveness of the device is demonstrated through experimental validation on a simple Y-shaped specimen subjected to fatigue loading. The results show that the device can accurately detect structural damage and provide real-time feedback on the health status of the structure. The low-cost and easy-to-implement nature of the device makes it promising for use in structural health monitoring applications in various industrial sectors.