Embedded two-photon polymerized microscale multiaxial sensor for strain monitoring

Embedded sensors enable real-time monitoring of mechanical parameters within materials and structures. To minimize the impact on structural performance due to embedding the device, minimal sensor size and quantity are preferred. Additionally, improving bonding between the embedded sensor and the monitored object, without the use of additional adhesives, is essential for accurate measurement. This paper investigates the performance of a miniaturized multiaxial sensor produced via two-photon polymerization (2PP), which offers high precision in fabricating microstructures to address these challenges. The sensor features star-shaped microchannels aligned with the geometrical axes, filled with electrodes for signal detection. Adhesive microstructures are patterned onto the sensor surface to increase the bonding surface area, resulting in enhanced attachment between the sensor and the monitored specimen during embedding. This research advances the development of miniaturized multiaxial sensors for real-time strain monitoring, as well as enhances the structural integrity and reliability of embedded sensors in mechanical and aerospace applications.