Microsystem Technologies

, Volume 24, Issue 8, pp 3455–3465 | Cite as

Catheter type thermal flow sensor with small footprint for measuring breathing function

  • Y. HasegawaEmail author
  • H. Kawaoka
  • Y. Mitsunari
  • M. Matsushima
  • T. Kawabe
  • M. Shikida
Technical Paper


We preivously developed a catheter type flow sensor for measuring breathing and heartbeat information from breathing at the mouth [Hasegawa et al. J Micromech Microeng 27(12): 125016, (2017); Kawaoka et al. Tech. Dig. IEEE Micro Electro Mechanical Systems Conference 2016, pp 359–362]. In this study, we redesigned and developed the new sensor configuraiton for the catheter flow sensor to downsize and improve the sensor characteristics. The previous flow sensor consists of two pairs of a heater and a temperature compensation sensor for flow rate detection. The two heaters also functioned not only for flow rate detection but also for flow direction detection. The two temperature compensation sensors had a large footprint and corresponded to each heater. Therefore, the sensor occupied a large area, and it was necessary to match the heater characteristics for flow rate detection. The newly designed sensor is composed of a set of a heater and a temperature compensation sensor and two flow direction sensors. By providing the new flow direction sensors, the number of temperature compensation sensors with a large footprint was reduced to one. Thus, the area of the new sensor design was 15.0 mm2, which was reduced to 54.5% of the 27.0 mm2 of the previous sensor area by providing the flow direction sensors. Then, the new catheter type flow sensor was fabricated, and the flow characteristics for measuring breathing funciton were evaluated. Finally, we applied the catheter type flow sensor to an animal experiment using a rat, and it could evaluate the flow rate characteristics of the rat’s breathing as a reciprocating flow including flow direction. Moreover, the obtained breathing characteristics were within the range of the physiological values of rats.



This research was supported by The Canon Foundation and JSPS KAKENHI Grant Number 26286034, Japan.


  1. Chandra NC, Hazinski MF (1997) American Red cross basic life support for healthcare providers handbook. American Red Cross, Washington, D.C.Google Scholar
  2. Demirci U, Oralkan O, Johnson JA, Ergun AS, Karaman M, Khuri-Yakub BT (2001) Capacitive micromachined ultrasonic transducer arrays for medical imaging: experimental results. In: Ultrasonics Symposium, 2001 IEEE, Atlanta GA, vol 2, pp 957–960, 7–10 Oct 2001Google Scholar
  3. Hasegawa Y, Kawaoka H, Yamada T, Matsushima M, Kawabe T, Shikida M (2017) Respiration and heartbeat signal detection from airflow at airway in rat by catheter flow sensor with temparature compensation function. J Micromech Microeng 27(12):125016CrossRefGoogle Scholar
  4. Jovanov E, Raskovic D, Hormigo R (2001) Thermistor-based breathing sensor for circadian rhythm evaluation. In: Proc. 38th Annu. Rocky Mountain Bioengineering Symp. RMBS 2001, pp 493–497, 2001 AprGoogle Scholar
  5. Kawaoka H, Yamada T, Matsushima M, Kawabe T, Shikida M (2015a) Detection of both heartbeat and respiration signals from airflow at mouth by using single catheter flow sensor. In: Tech. Digest of the 18th international conference on solid-state sensors, actuators and microsystems, Anchorage, USA, 2015, pp 1755–1758Google Scholar
  6. Kawaoka H, Yamada T, Matsushima M, Kawabe T, Hasegawa Y, Shikida M (2015b) Extraction of heartbeat signal from airflow at mouth by flow sensor. In: Proceedings of IEEE sensors conference, Busan, Nov 2015, pp 279–282Google Scholar
  7. Kawaoka H, Yamada T, Matsushima M, Kawabe T, Hasegawa Y, Shikida M (2016) Detection of kinetic heartbeat signals from airflow at mouth by catheter flow sensor with temperature compensation. In: Tech Dig IEEE micro electro mechanical systems conference, Shanghai, China, Jan 2016, pp 359–362Google Scholar
  8. Kawaoka H, Yamada T, Matsushima M, Kawabe T, Hasegawa Y, Shikida M (2017) Heartbeat signal detection from analysis of airflow in rat airway under different depths of anesthesia conditions. IEEE Sens J 17(14):4369–4377CrossRefGoogle Scholar
  9. Khuri-Yakub BT, Oralkan O (2011) Capacitive micromachined ultrasonic transducers for medical imaging and therapy. J Micromech Microeng 21(5):54004–54015CrossRefGoogle Scholar
  10. King LV (1914) On the convection of heat from small cylinders in a stream of fluid: determination of the convection constants of small platinum wires with applications to hot-wire anemometry. Philos Trans R Soc Lond A 214:373–432CrossRefGoogle Scholar
  11. Liu LY, Keeler EG (2015) Progress of MEMS scanning micromirrors for optical bio-imaging. Micromachines 6:1675–1689CrossRefGoogle Scholar
  12. Lu CD, Kraus MF, Potsaid B (2014) Handheld ultrahigh speed swept source optical coherence tomography instrument using a MEMS scanning mirror. Biomed Opt Express 5:293–311CrossRefGoogle Scholar
  13. Mitsunari Y, Hasegawa Y, Matsushima M, Kawabe T, Shikida M (2017) Development of small-footprint thermal sensor detecting airflow at mouth in baby. In: Proceedings of Eurosensors2017 conference.
  14. Shikida M, Naito J, Yokota T, Kawabe T, Hayashi Y, Sato K (2009) A catheter-type flow sensor for measurement of aspirated- and inspired-air characteristics in the bronchial region. J Micromech Microeng 19:105027CrossRefGoogle Scholar
  15. Shikida M, Yokota T, Kawabe T, Funaki T, Matsushima M, Iwai S, Matsunaga N, Sato K (2010) Characteristics of an optimized catheter-type thermal flow sensor for measuring reciprocating airflows in bronchial pathways. J Micromech Microeng 20:125030CrossRefGoogle Scholar
  16. Shikida M, Yoshikawa K, Matsuyama T, Yamazaki Y, Matsushima M, Kawabe T (2014) Catheter flow sensor with temperature compensation for tracheal intubation tube system. Sens Actuators A 215:155–160CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Biomedical Information SciencesHiroshima City UniversityHiroshimaJapan
  2. 2.Department of Frontier SciencesHiroshima City UniversityHiroshimaJapan
  3. 3.Department of Medical TechnologyNagoya UniversityNagoyaJapan

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