Research ArticleAPPLIED SCIENCES AND ENGINEERING

Soft sensors for a sensing-actuation system with high bladder voiding efficiency

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Science Advances  01 May 2020:
Vol. 6, no. 18, eaba0412
DOI: 10.1126/sciadv.aba0412
  • Fig. 1 The sensing-actuation bladder system and micturition.

    (A) The schematic of the integrated capacitive sensor with the SMA-based actuator. (B) The top view SEM (scale bar, 500 μm), magnified cross-section SEM (scale bar, 100 μm), and (Inset) the optical image of the wrinkled interdigitated electrodes (scale bar, 50 μm). The blue arrows present the formed two wrinkles on each adjacent electrode, and the orange arrow shows the gap between the electrodes. (C) The schematic side view of the integrated bladder system during the storage, compression, and restoration phases. The enlarged schematic side view presents two adjacent electrodes with a gap, perpendicular (F1), and bending (F2) forces applied to the sensor during the storage phase. (D) The schematic of the micturition stages by using the integrated bladder system for a rat.

  • Fig. 2 The interdigitated capacitive sensor and multifunctional sensing.

    (A) The steps for preparing wrinkled interdigitated electrodes on a prestretched acrylic elastomer. (B) The optical top view image of the wrinkled electrodes. Scale bar, 5 mm. Photo credit: Faezeh Arab Hassani, National University of Singapore and University of Tokyo. (C) Schematic view of the gap without deformation and with deformation due to the perpendicular force (F1) and bending forces (F2). (D) The capacitance characteristics of the sensor due to changes of F1 and bending radius (R).

  • Fig. 3 In vitro characteristics of the integrated bladder system.

    (A) The schematic of the in vitro setup. (B) The capacitance characteristics of the sensor during the storage phase with three filling rates. (Inset) Schematic side views of the system before and after the storage phase completion. (C) The voiding (diamond dotted line) and capacitance (circle dotted line) characteristics of the integrated bladder system during the compression phase. (Inset) Schematic side views of the system during various compression phase points. The gray sections present the duration of turning the voltage ON. (D) The capacitance characteristics of the integrated bladder system during the restoration phase. (Inset) Schematic side views of the system during various points of the restoration phase. The gray section presents the duration of turning the voltage ON.

  • Fig. 4 In vivo characteristics of the integrated bladder system.

    (A) The schematic of the in vivo setup. (B) The implanted integrated bladder system on an anesthetized rat’s bladder. Scale bar, 5 mm. Photo credit: Faezeh Arab Hassani, National University of Singapore and University of Tokyo. (C) The capacitance characteristics of the sensor during the bladder storage. (Inset) Schematic side views of the system before and after the storage phase completion. (D) The capacitance characteristics of the integrated bladder system during the compression phase. (Inset) The voiding percentage for the three rats. (Below inset) Schematic side views of the system before and after the compression phase completion. The gray sections present the duration of ON voltage. (E) The capacitance characteristics of the integrated bladder system during the restoration phase. (Inset) Schematic side views of the system before and after the restoration phase completion. The gray sections present the duration of ON voltage.

Supplementary Materials

  • Supplementary Materials

    Soft sensors for a sensing-actuation system with high bladder voiding efficiency

    F. Arab Hassani, H. Jin, T. Yokota, T. Someya, N. V. Thakor

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    The PDF file includes:

    • The gauge factor evaluation for the interdigitated capacitive sensor
    • Parallel-plate capacitive sensor fabrication and characterization
    • In vitro repeatability test of the bladder system
    • In vitro evaluation of the bladder system with incomplete/ no voiding
    • In vitro evaluation of the bladder system with 1200-nm-thick parylene coating
    • In vivo repeatability test of the bladder system
    • In vivo evaluation of the bladder system with no voiding
    • In vivo evaluation of the bladder system with 1200-nm-thick parylene coating
    • Figs. S1 to S7
    • Table S1
    • Legends for movies S1 to S8
    • References

    Other Supplementary Material for this manuscript includes the following:

    Files in this Data Supplement:

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