Experimental Characterization of an Ionically Conductive Fluid Based High Flexibility Strain Sensor

  • Chi Tran Nhu
  • Ha Tran Thi Thuy
  • An Tran Hoai
  • Nguyen Ta Hoang
  • Hoai Nguyen Thi
  • An Nguyen Ngoc
  • Trinh Chu Duc
  • Van Thanh Dau
  • Tung Thanh BuiEmail author
Conference paper
Part of the Lecture Notes in Networks and Systems book series (LNNS, volume 63)


In this study, a high flexibility strain sensor based on ionic liquid, which is a mixture of aqueous sodium chloride and glycerin pump in silicone tube, is developed. Gold-coated electrodes are inserted into both ends of the tube to make good contact with the liquid. When the silicone tube is affected by an external force, its geometry and electrical characteristics of the mixture inside the tube are changed, resulting in the change in the sensor resistance. The proposed sensor was fabricated and experimentally characterized. The 4-point resistance measurement based on alternating Howland current source was applied to the sensor for measuring the change in resistance of the sensor. A circuit board with PIC16F877A microcontroller is also developed for data acquisition and result display. Experimental results show that the sensor is highly flexible, i.e., can suffer from a stretch up to 50% with stable gauge factor in the range of 2.1 to 2.47. With its simplexes and high-flexibility, the proposed sensor has high potential to be applied to wearable and portable applications.


Strain sensor Gauge factor (GF) Ionic liquid 



This work has been supported by Vietnam National University, Hanoi (VNU), under Project No. QG.17.69.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Chi Tran Nhu
    • 1
  • Ha Tran Thi Thuy
    • 2
  • An Tran Hoai
    • 1
  • Nguyen Ta Hoang
    • 1
  • Hoai Nguyen Thi
    • 1
  • An Nguyen Ngoc
    • 1
  • Trinh Chu Duc
    • 1
  • Van Thanh Dau
    • 3
  • Tung Thanh Bui
    • 1
    Email author
  1. 1.VNU – University of Engineering and TechnologyHanoiVietnam
  2. 2.Posts and Telecommunications Institute of TechnologyHanoiVietnam
  3. 3.Research Group (Environmental Health)Sumitomo Chemical Ltd.TakarazukaJapan

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