Flexible, wide strain sensing range and lightweight sensors are showing increasing significance in structural health monitoring compared with conventional hard sensors which typically have a small strain range, heavyweight, and large volume. In this work, salt particle precipitation and mechanical coating methods are used to fabricate porous graphene platelet (GNP)/polydimethylsiloxane (PDMS) flexible sensors for tension health monitoring. The signal transformation through the Back Propagation (BP) algorithm is integrated to allow the overall monitoring data comparable with other sensors. The results reveal that the flexible sensor with low content of GNP (0.1 wt%-0.25 wt%) leads to better flexibility, allowing tensile strains are all over 200%. In addition, due to the enhanced deformation capacity of the pore structures, it reaches high sensitivity (1-1000) under 65% strain and a fast response time (70 ms) under 5% strain at 60 mm/min. It also shows high performance through the fatigue test (20,000 cycles) under 5% strain and can effectively responds to bending and torsion. Meantime, the sensor shows an obvious response to temperature. Overall, the prepared ﬂexible composite sensor in this work has the advantages of wide strain sensing range, full coverage conductive network, and lightweight, and shows the potential in structure health monitoring in the near future.
Bibliographical noteOpen Access CC BY NC
- Tension monitoring
- Porous flexible film
- High sensitivity