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Flexible CNT/silicon piezo-resistive strain sensors geometrical influences on sensitivity for human motion detection

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Abstract

Developing flexible, extremely sensitive strain sensors with a broad operating range is critical for applications such as healthcare, human motion, human–machine interface, and robotics. The COMSOL Multiphysics Finite Element Modeling software has been used to simulate serpentine geometry CNT-silicon-based flexible piezo-resistive (PZR) strain sensors with various sensor line thicknesses (LT), line widths (LW), pitches (P), and structures (Str whereby Str1 is P in the x-direction, and Str2 is P in the y-direction). Their effect on mechanical and piezo-resistive characteristics for strain ranging from 0 to 100% has been studied. The responses of the proposed modeled sensors have been simulated and analyzed in terms of numerous variables, including maximum displacement, von Mises stress, and sensor sensitivity. The simulation study concluded that for the Str1 structure, the PZR strain sensor with P (0.5 mm), LT (0.5 mm), and LW (1.5 mm) had the highest sensitivity (GF 120.50), while the PZR strain sensor with P (0.5 mm), LT (0.5 mm), and LW (1.5 mm) had the lowest sensitivity (GF 48.99). It is also found that the sensitivity of the Str1 PZR strain sensors rises when LW increases while P and LT decrease. Furthermore, the PZR strain sensor with P (0.5 mm), LT (0.5 mm), and LW (1 mm) of structure Str2 has the highest sensitivity (GF 165.95), and the PZR strain sensor with P (1.5 mm), LT (0.5 mm) and LW (0.5 mm) showed the lowest sensitivity (GF 161.62) among all the Str2 sensors, and it is revealed that the sensitivity increases with the decrease of P and LT while the effect of LT is not apparent. As a result, the modeled sensor can be employed as a highly sensitive PZR strain sensor with an excellent capability to monitor a wide range of human motions over the range of 0–100% strain.

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Data availability

The datasets generated during and analyzed during the current study are not publicly but are available from the corresponding author on reasonable request.

References

  1. Du, J., et al.: Optimized CNT-PDMS flexible composite for attachable health-care device. Sensors 20(16), 4523 (2020)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  2. Duan, L., D’Hooge, D.R., Cardon, L.: Recent progress on flexible and stretchable piezoresistive strain sensors: from design to application. Prog. Mater. Sci. 114, 100617 (2020)

    Article  Google Scholar 

  3. Chu, Z., et al.: Superhydrophobic gradient wrinkle strain sensor with ultra-high sensitivity and broad strain range for motion monitoring. J. Mater. Chem. A 9(15), 9634–9643 (2021)

    Article  CAS  Google Scholar 

  4. Baloda, S., et al.: Development and analysis of graphene nanoplatelets (GNPS)-based flexible strain sensor for health monitoring applications. IEEE Sens. J. 20(22), 13302–13309 (2020)

    Article  ADS  CAS  Google Scholar 

  5. Chen, X., et al.: High-sensitivity, fast-response flexible pressure sensor for electronic skin using direct writing printing. RSC Adv. 10(44), 26188–26196 (2020)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  6. Won, P., et al.: Transparent soft actuators/sensors and camouflage skins for imperceptible soft robotics. Adv. Mater. 33(19), 2002397 (2021)

    Article  CAS  Google Scholar 

  7. An, T., et al.: Self-powered gold nanowire tattoo triboelectric sensors for soft wearable human-machine interface. Nano Energy 77, 105295 (2020)

    Article  CAS  Google Scholar 

  8. Aroganam, G., Manivannan, N., Harrison, D.: Review on wearable technology sensors used in consumer sport applications. Sensors 19(9), 1983 (2019)

    Article  ADS  PubMed  PubMed Central  Google Scholar 

  9. Yeo, J.C., Lim, C.T.: Emerging flexible and wearable physical sensing platforms for healthcare and biomedical applications. Microsyst. Nanoeng. 2, 16043 (2016)

    Article  PubMed  PubMed Central  Google Scholar 

  10. Wen, N., et al.: Emerging flexible sensors based on nanomaterials: recent status and applications. J. Mater. Chem. A 8(48), 25499–25527 (2020)

    Article  CAS  Google Scholar 

  11. Gu, Y., et al.: Mini review on flexible and wearable electronics for monitoring human health information. Nanoscale Res. Lett. 14(1), 1–15 (2019)

    Article  ADS  CAS  Google Scholar 

  12. Heo, J.S., Hossain, M.F., Kim, I.: Challenges in design and fabrication of flexible/stretchable carbon-and textile-based wearable sensors for health monitoring: a critical review. Sensors 20(14), 3927 (2020)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  13. Gao, Y., et al.: Flexible hybrid sensors for health monitoring: materials and mechanisms to render wearability. Adv. Mater. 32(15), 1902133 (2020)

    Article  CAS  Google Scholar 

  14. Nag, A., et al.: Multi-walled carbon nanotubes-based sensors for strain sensing applications. Sensors 21(4), 1261 (2021)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  15. Homayounfar, S.Z., Andrew, T.L.: Wearable sensors for monitoring human motion: a review on mechanisms, materials, and challenges. SLAS TECHNOL Transl. Life. Sci. Innov. 25(1), 9–24 (2020)

    Google Scholar 

  16. Afsarimanesh, N., et al.: A review on fabrication, characterization and implementation of wearable strain sensors. Sens. Actuators A Phys. 315, 112355 (2020)

    Article  CAS  Google Scholar 

  17. Qiao, Y., et al.: Graphene-based wearable sensors. Nanoscale 11(41), 18923–18945 (2019)

    Article  CAS  PubMed  Google Scholar 

  18. Qiu, A., et al.: A path beyond metal and silicon: polymer/nanomaterial composites for stretchable strain sensors. Adv. Func. Mater. 29(17), 1806306 (2019)

    Article  Google Scholar 

  19. Cheng, M., et al.: An review of flexible force sensors for human health monitoring. J. Adv. Res. 26, 53–68 (2020)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  20. De Meo, E., et al.: Piezoresistive and mechanical behavior of CNT based polyurethane foam. J. Compos. Sci. 4(3), 131 (2020)

    Article  Google Scholar 

  21. Huang, K., et al.: Ultrasensitive MWCNT/PDMS composite strain sensor fabricated by laser ablation process. Compos. Sci. Technol. 192, 108105 (2020)

    Article  CAS  Google Scholar 

  22. Cattin, C., Hubert, P.: Piezoresistance in polymer nanocomposites with High aspect ratio particles. ACS Appl. Mater. Interfaces 6, 1804 (2014)

    Article  CAS  PubMed  Google Scholar 

  23. Hegde, R., Ramji, K., Swapna, P (2018) Simulation of carbon nanotubes polymer based piezoresistive flexible pressure sensor for ultra sensitive electronic skin. In 2018 2nd International conference on electronics, Mater. Eng. Nano-Technol. (IEMENTech). IEEE

  24. Amjadi, M., et al.: Stretchable, skin-mountable, and wearable strain sensors and their potential applications: a review. Adv. Func. Mater. 26(11), 1678–1698 (2016)

    Article  CAS  Google Scholar 

  25. Kumar, S., Gupta, T.K., Varadarajan, K.: Strong, stretchable and ultrasensitive MWCNT/TPU nanocomposites for piezoresistive strain sensing. Compos. B Eng. 177, 107285 (2019)

    Article  CAS  Google Scholar 

  26. Nankali, M., et al.: Electrical properties of stretchable and skin–mountable PDMS/MWCNT hybrid composite films for flexible strain sensors. J. Compos. Mater. 53(21), 3047–3060 (2019)

    Article  ADS  Google Scholar 

  27. Huang, Y.-T., et al.: Design and fabrication of single-walled carbon nanonet flexible strain sensors. Sensors 12(3), 3269–3280 (2012)

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  28. Choong, C.L., et al.: Highly stretchable resistive pressure sensors using a conductive elastomeric composite on a micropyramid array. Adv. Mater. 26, 3451 (2014)

    Article  CAS  PubMed  Google Scholar 

  29. Liu, Y., et al.: Flexible, stretchable sensors for wearable health monitoring: sensing mechanisms, materials. Fabr. Strateg. Features Sens. 18(2), 645 (2018)

    Google Scholar 

  30. Sreenilayam, S.P., et al.: Advanced materials of printed wearables for physiological parameter monitoring. Mater. Today 32, 147–177 (2020)

    Article  Google Scholar 

  31. Chen, W., Yan, X.: Progress in achieving high-performance piezoresistive and capacitive flexible pressure sensors: a review. J. Mater. Sci. Technol. 43, 175–188 (2020)

    Article  CAS  Google Scholar 

  32. Xu, K., et al.: Highly stable kirigami-structured stretchable strain sensors for perdurable wearable electronics. J. Mater. Chem. C 7(31), 9609–9617 (2019)

    Article  CAS  Google Scholar 

  33. Ramírez, J., et al.: Combining high sensitivity and dynamic range: wearable thin-film composite strain sensors of graphene, ultrathin palladium, and PEDOT: PSS. ACS appl. Nano mater. 2(4), 2222–2229 (2019)

    Article  PubMed  PubMed Central  Google Scholar 

  34. Sandrimani, V., Balavalad, K.B.: Design and simulation of silicon on insulator based piezoresistive pressure sensor. Int. J. Eng. Sci. 8(8), 18814–18819 (2018)

    Google Scholar 

  35. Alpuim, P., et al.: Fabrication of a strain sensor for bone implant failure detection based on piezoresistive doped nanocrystalline silicon. J. Non-Cryst. Solids 354(19–25), 2585–2589 (2008)

    Article  ADS  CAS  Google Scholar 

  36. Farhath, M., Samad, M.: Design and simulation of a high sensitive stripped-shaped piezoresistive pressure sensor. J. Comput. Electron. 19(1), 310–320 (2020)

    Article  CAS  Google Scholar 

  37. Christ, J.F., et al.: 3D printed highly elastic strain sensors of multiwalled carbon nanotube/thermoplastic polyurethane nanocomposites. Mater. Des. 131, 394–401 (2017)

    Article  CAS  Google Scholar 

  38. Al-Rubaiai, M., et al.: A 3D-printed stretchable strain sensor for wind sensing. Smart Mater. Struct. 28(8), 084001 (2019)

    Article  ADS  CAS  Google Scholar 

  39. Kim, J., Campbell, A.S., Wang, J.: Wearable non-invasive epidermal glucose sensors: a review. Talanta 177, 163–170 (2018)

    Article  CAS  PubMed  Google Scholar 

  40. Ji, B., et al.: Stretchable Parylene-C electrodes enabled by serpentine structures on arbitrary elastomers by silicone rubber adhesive. J. Mater. 6(2), 330–338 (2020)

    Google Scholar 

  41. Singh, K., et al.: Fabrication of serpentine and I structured graphene-CNT based highly sensitive and flexible strain sensors. Microelectron. Eng. 250, 111631 (2021)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This research has been financially supported by the Malaysian Ministry of Higher Education, FRGS Grant (FRGS/1/2019/TK05/UM/02/4), and partial support from the University of Malaya Research Grant (UM.0000679/HRU.OP.RF/GPF047A-2018), Faculty of Engineering, University of Malaya.

Funding

Author S.M.Ahmed is funded by the grant stated in the Acknowledgment section. The datasets generated during and analysed during the current study are not publicly but are available from the corresponding author on reasonable request.

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Correspondence to Sharifah Fatmadiana Wan Muhamad Hatta.

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Ahmed, S.M., Soin, N., Hatta, S.F.W.M. et al. Flexible CNT/silicon piezo-resistive strain sensors geometrical influences on sensitivity for human motion detection. J Comput Electron (2024). https://doi.org/10.1007/s10825-024-02135-y

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  • DOI: https://doi.org/10.1007/s10825-024-02135-y

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