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Piezoelectric soft material based on inorganic/organic composites suitable for aerospace and aeronautical monitoring sensors is fabricated. The designed material is a piezoelectric composite made of lead zirconate titanate (PZT) filler embedded in a poly(dimethyl siloxane) (PDMS) matrix. To improve the piezoelectric properties of the film, the connectivity of the ceramic filler is increased via electric field‐assisted structuration, which leads to columnar arrangement of the filler across the thickness. This structure (1–3) shows higher piezoelectricity than one with randomly dispersed filler (0–3). Piezoelectric and dielectric activities of PZT/PDMS in 0–3 and 1–3 configurations at different volume fractions are compared. The results confirm that the 1–3 connectivity leads to superior piezoelectric behavior. Thermal stability of electroactive properties and high temperature X‐ray diffraction (XRD) analyses are performed: the composites maintain a good piezoelectric response, even at 200 °C. Following a process optimization, the piezoelectric behavior of this new class of composites approaches the fluorinated ferroelectric polymers one, with the advantages of piezoelectric properties stability preserved at a higher temperature and a lower poling electric field. In conclusion, there is potential for the integration of the designed sensor in aircraft ball bearings for condition monitoring.

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This paper reports a novel monitoring technique of bearings’ bidirectional load (axial and radial) based on a smart sensor coating, which is screen printed onto the surface of a cross-shaped steel substrate. To ensure the accuracy and stability of measurement as well as the durability of the printed coating, the developed prototype is built according to design rules commonly used in electronic circuits. The finite element model (FEM) is used to predict the mechanical property of the tested substrate under either unidirectional or bidirectional loads. Regarding the output voltage of the piezoelectric sensor, experimental results are revealed to be well-corelated to the numerical simulation. It is pointed out that the output signal generated from the sensor (electrode) could be particularly affected due to the capacitive parasite coming from the conductive tracks (CTs). Such a phenomenon might be reduced by printing them on the dielectric layer rather than on the piezocomposite layer. The study also investigates a highly anisotropic shape of electrodes (rectangular instead of circle), indicating that the orientation of such electrodes (axial or radial) does affect the output measurement. To sum up, the high performance of a sensor network coating depends not only on the ultimate characteristics of its own materials, but also on its structural design. Such an issue has been rarely reported on in the literature, but is nonetheless crucial to achieving reliable condition monitoring of bearings, especially for multidirectional loads—a key signature of early failure detection.

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