Page 91 - IJAMD-2-3

International Journal of AI for
Materials and Design SHM using improved CNT-BP and LSTM-NN

(i) The ductility of the fabricated CNT-BP is enhanced with The electrode arrangements must be varied according to
the improved fabrication process. This is paramount the location and direction of the crack propagation. This
because if the CNT-BP is brittle, it can be difficult to would give further insights for optimizing the sensing
handle and may break while being glued to the test architecture for a specific application.
specimen. Furthermore, it may be relatively easy to (iv) Obtaining readings at different load levels and
superglue the ductile CNT-BP to the test specimen by directions.
tapping to ensure a uniform attachment of CNT-BP to the
specimen, avoiding any voids formation at the interface. In the present study, the load was tension-tension
(ii) The sensitivity of the fabricated BP is enhanced with controlled at a specific loading frequency. In future work,
the improved fabrication process, as demonstrated by both the loading amplitude and direction—ranging from
the marginal error between the actual and predicted tension to compression—and the loading frequency can be
results of fatigue crack. The piezoresistivity is improved varied to further evaluate the reliability of CNT-BP in the
up to 5.8 Ω compared to the earlier reported values prognosis and diagnosis of fatigue in specimens.
between 4 Ω and 5 Ω.
(iii) The error analysis shows the potential of CNT-BP in Acknowledgments
crack length estimation with enhanced accuracy and None.
sensitivity.
(iv) For higher crack length estimation, an approximate Funding
linear relationship seems to exist, indicating that None.
the LSTM model can predict the trend with higher
accuracy. Conflict of interest
(v) The use of CNT-BP as a self-sensing material eliminates
the need for sophisticated equipment and sensors, Faeez Masurkar is the Youth Editorial Board Member
complex signal processing, and high computational of this journal, but was not in any way involved in the
resources. Further, CNT-BP can be easily affixed to the editorial and peer-review process conducted for this paper,
test structure, and changes in its electrical resistance directly or indirectly.
can be readily measured.
(vi) The omnidirectional shape of the CNT-BP can Author contributions
facilitate the detection of cracks in different directions This is a single-authored article.
with higher sensitivity.
In contrast, the current work identified several Ethics approval and consent to participate
limitations that could be explored in future studies. The Not applicable.
limitations are as follows:
Consent for publication
(i) Limited BP size due to the filter membrane size.
Not applicable.
To yield CNT-BP with larger sizes, a flask with a bigger
funnel width, membrane, and pore sizes must be employed Availability of data
during the fabrication process. This could also facilitate The data presented in this study are available from the
mass fabrication since smaller pieces with equal sizes and corresponding author on request.
shapes can be cut out of the large BP, thereby reducing
the fabrication time. The fabrication of BP into different References
shapes and sizes for future testing may lead to further
overall optimization of the sensing architecture. 1. Masurkar F, Tse PW, Yelve NP. Theoretical and experimental
measurement of intrinsic and fatigue induced material
(ii) Different crack directions. nonlinearities using Lamb wave based nonlinearity
In this work, only the crack propagating perpendicular to parameters. Measurement. 2020;151:107148.
the loading direction was considered. The CNT-BP must doi: 10.1016/j.measurement.2019.107148
be tested for different crack directions to further investigate 2. Tse P, Masurkar F, Yelve NP. Estimation of remaining useful
and confirm the reliability of its sensing efficiency and use life of fatigued plate specimens using Lamb wave-based
in prognosis and diagnosis of fatigued specimens. nonlinearity parameters. Struct Control Health Monit.
(iii) Different electrode arrangements for damage detection 2020;27(4):e2486.
and quantification. doi: 10.1002/stc.2486

Volume 2 Issue 3 (2025) 85 doi: 10.36922/IJAMD025310028