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An interactive mouthguard based on mechanoluminescence-powered optical fibre sensors for bite-controlled device operation

Abstract

Keyboards and touchscreens are widely used to control electronic devices, but these can be difficult to operate for individuals with dexterity impairments or neurological conditions. Several assistive technologies, such as voice recognition and eye tracking, have been developed to provide alternate methods of control. However, these can have problems in terms of use and maintenance. Here we report a bite-controlled optoelectronic system that uses mechanoluminescence-powered distributed-optical-fibre sensors that are integrated into mouthguards. Phosphors that are sensitive to mechanical stimulus are arranged in an array of contact pads in a flexible mouthguard; by using unique patterns of occlusal contacts in lateral positions, various forms of mechanical deformation can be distinguished by the fibre sensors via ratiometric luminescence measurements. By combining the device with machine learning algorithms, it is possible to translate complex bite patterns into specific data inputs with an accuracy of 98%. We show that interactive mouthguards can be used to operate computers, smartphones and wheelchairs.

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Fig. 1: Design of interactive mouthguard based on mp-DOF sensors.
Fig. 2: Characterization of mp-DOF-based sensors in various configurations.
Fig. 3: Evaluation of mp-DOF-integrated interactive mouthguard.
Fig. 4: Interactive mouthguard with a 2 × 3 mp-DOF array for assistive technology demonstration.
Fig. 5: Efficacy of the ANN-based interactive mouthguard using occlusal data from two users on specific tasks.

Data availability

The data that support the plots within this paper and other findings of the study are available from the corresponding authors upon reasonable request.

Code availability

The code is available from the corresponding authors upon reasonable request.

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Acknowledgements

This work is supported by the Ministry of Education Singapore (grant R-143-000-B43-114); Agency for Science, Technology and Research (A*STAR) (grant A1983c0038); National Research Foundation, Prime Minister’s Office, Singapore (CRP award no. NRF-NRFI05-2019-003 and NRF-CRP19-2017-01); National Basic Research Program of China (973 Program, grant 2015CB932200); and National Key R&D Program of China (YS2018YFB110012). We thank Yongan Tang, Zhuang Liu and Yong Zuo for their technical assistance.

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Contributions

X.L., L.Y. and B.H. conceived and designed the project. X.L., B.Z. and R.Z. supervised the project and led the collaboration efforts. L.Y. characterized the materials and conducted the numerical simulations. C.L. completed the electrical device fabrication. B.H., L.Y. and H.Z. performed the luminescence measurements and conducted the experimental validation. B.H. and L.Y. wrote the manuscript. X.L., B.Z. and R.Z. edited the manuscript. All the authors participated in the discussion and analysis of the manuscript.

Corresponding authors

Correspondence to Bin Zhou or Xiaogang Liu.

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The authors declare no competing interests.

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Nature Electronics thanks Lin Dong, Meidan Ye and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–13 and Tables 1 and 2.

Supplementary Video 1

Characteristic of mp-DOF.

Supplementary Video 2

Keyboard type.

Supplementary Video 3

Wheelchair control and playing the piano.

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Hou, B., Yi, L., Li, C. et al. An interactive mouthguard based on mechanoluminescence-powered optical fibre sensors for bite-controlled device operation. Nat Electron 5, 682–693 (2022). https://doi.org/10.1038/s41928-022-00841-8

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