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Title: Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring

Abstract

Flexible pressure sensors have many potential applications in wearable electronics, robotics, health monitoring, and more. In particular, liquid-metal-based sensors are especially promising as they can undergo strains of over 200% without failure. However, current liquid-metal-based strain sensors are incapable of resolving small pressure changes in the few kPa range, making them unsuitable for applications such as heart-rate monitoring, which require a much lower pressure detection resolution. In this paper, a microfluidic tactile diaphragm pressure sensor based on embedded Galinstan microchannels (70 µm width × 70 µm height) capable of resolving sub-50 Pa changes in pressure with sub-100 Pa detection limits and a response time of 90 ms is demonstrated. An embedded equivalent Wheatstone bridge circuit makes the most of tangential and radial strain fields, leading to high sensitivities of a 0.0835 kPa-1 change in output voltage. The Wheatstone bridge also provides temperature self-compensation, allowing for operation in the range of 20–50 °C. Finally, as examples of potential applications, a polydimethylsiloxane (PDMS) wristband with an embedded microfluidic diaphragm pressure sensor capable of real-time pulse monitoring and a PDMS glove with multiple embedded sensors to provide comprehensive tactile feedback of a human hand when touching or holding objects are demonstrated.

Authors:
 [1];  [2];  [3];  [2];  [3];  [2];  [3];  [4];  [5];  [4];  [3];  [2];  [2];  [3];  [2]
  1. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tianjin Univ. (China)
  2. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  3. Univ. of California, Berkeley, CA (United States)
  4. Tianjin Univ. (China)
  5. Bournemouth Univ. (United Kingdom)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES), Materials Sciences & Engineering Division; National Science Foundation (NSF)
OSTI Identifier:
1642665
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Advanced Materials
Additional Journal Information:
Journal Volume: 29; Journal Issue: 39; Journal ID: ISSN 0935-9648
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; diaphragm pressure sensors; flexible pressure sensors; liquid metal; microfluidics; wearable

Citation Formats

Gao, Yuji, Ota, Hiroki, Schaler, Ethan W., Chen, Kevin, Zhao, Allan, Gao, Wei, Fahad, Hossain M., Leng, Yonggang, Zheng, Anzong, Xiong, Furui, Zhang, Chuchu, Tai, Li-Chia, Zhao, Peida, Fearing, Ronald S., and Javey, Ali. Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring. United States: N. p., 2017. Web. doi:10.1002/adma.201701985.
Gao, Yuji, Ota, Hiroki, Schaler, Ethan W., Chen, Kevin, Zhao, Allan, Gao, Wei, Fahad, Hossain M., Leng, Yonggang, Zheng, Anzong, Xiong, Furui, Zhang, Chuchu, Tai, Li-Chia, Zhao, Peida, Fearing, Ronald S., & Javey, Ali. Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring. United States. https://doi.org/10.1002/adma.201701985
Gao, Yuji, Ota, Hiroki, Schaler, Ethan W., Chen, Kevin, Zhao, Allan, Gao, Wei, Fahad, Hossain M., Leng, Yonggang, Zheng, Anzong, Xiong, Furui, Zhang, Chuchu, Tai, Li-Chia, Zhao, Peida, Fearing, Ronald S., and Javey, Ali. 2017. "Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring". United States. https://doi.org/10.1002/adma.201701985. https://www.osti.gov/servlets/purl/1642665.
@article{osti_1642665,
title = {Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring},
author = {Gao, Yuji and Ota, Hiroki and Schaler, Ethan W. and Chen, Kevin and Zhao, Allan and Gao, Wei and Fahad, Hossain M. and Leng, Yonggang and Zheng, Anzong and Xiong, Furui and Zhang, Chuchu and Tai, Li-Chia and Zhao, Peida and Fearing, Ronald S. and Javey, Ali},
abstractNote = {Flexible pressure sensors have many potential applications in wearable electronics, robotics, health monitoring, and more. In particular, liquid-metal-based sensors are especially promising as they can undergo strains of over 200% without failure. However, current liquid-metal-based strain sensors are incapable of resolving small pressure changes in the few kPa range, making them unsuitable for applications such as heart-rate monitoring, which require a much lower pressure detection resolution. In this paper, a microfluidic tactile diaphragm pressure sensor based on embedded Galinstan microchannels (70 µm width × 70 µm height) capable of resolving sub-50 Pa changes in pressure with sub-100 Pa detection limits and a response time of 90 ms is demonstrated. An embedded equivalent Wheatstone bridge circuit makes the most of tangential and radial strain fields, leading to high sensitivities of a 0.0835 kPa-1 change in output voltage. The Wheatstone bridge also provides temperature self-compensation, allowing for operation in the range of 20–50 °C. Finally, as examples of potential applications, a polydimethylsiloxane (PDMS) wristband with an embedded microfluidic diaphragm pressure sensor capable of real-time pulse monitoring and a PDMS glove with multiple embedded sensors to provide comprehensive tactile feedback of a human hand when touching or holding objects are demonstrated.},
doi = {10.1002/adma.201701985},
url = {https://www.osti.gov/biblio/1642665}, journal = {Advanced Materials},
issn = {0935-9648},
number = 39,
volume = 29,
place = {United States},
year = {2017},
month = {8}
}

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Cited by: 117 works
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