Newsletter  2023.11  Index

Theme : "Mechanical Engineering Congress, 2023 Japan (MECJ-23)" Preface Hideo MORI, Tetsuya KANAGAWA Why do mistakes communicate and spread? (Diffusion and prevention of misperceptions regarding fluid mechanics) Ryozo ISHIWATA (Kanagawa Institute of Technology) Toward Digital Twin Numerical Turbine Satoru YAMAMOTO (Tohoku University) Measurements of turbulent wall pressure fluctuation field in a turbulent boundary layer and the wing-flat plate juncture flow using the many-channel microphone array Yoshitsugu NAKA (Meiji University) PSP and TSP for measuring pressure and temperature fields on wall surfaces and their applications Yasuhiro EGAMI (Aichi Institute of Technology) Flow measurement using MEMS differential pressure sensor Hidetoshi TAKAHASHI (Keio University), Takuto Kishimoto (Keio University), Kei Ohara (Keio University), Kyota Shimada (Keio University) Flexible Sheet Sensor for Advanced Flow Monitoring Masahiro MOTOSUKE (Tokyo University of Science)

 

Flow measurement using MEMS differential pressure sensor

Abstract

Hidetoshi TAKAHASHI Keio University	Takuto Kishimoto Keio University	Kei Ohara Keio University	Kyota Shimada Keio University

Here, we present the development of sensors for measuring various parameters in biofluids. These measurements include pressure differences observed during the flapping motion of butterfly wings and water velocity measurements during the swimming of sea turtles. Due to the stringent requirements associated with these measurements, the developed sensors hold significant engineering applications. Firstly, we designed a MEMS differential pressure sensor element employing a cantilever structure for easy deformation and a piezoresistor for heightened sensitivity. This sensor chip was affixed to the wing surface of a butterfly, revealing a pressure difference of ±10 Pa during takeoff motion. The developed differential pressure sensor has been adapted for use as an air vibration sensor to monitor low-frequency air vibrations during volcanic eruptions. Additionally, we have employed differential pressure sensors as sensing elements in a small airflow vector sensor for drones. Furthermore, we are in the process of developing a pitot-tube type waterflow sensor for marine biologging, utilizing a commercially available differential pressure sensor as the sensing element. In collaboration with the Enoshima Aquarium, we attached the sensor and logger to a sea turtle, and we are currently exploring the potential application of this sensor for monitoring ocean currents in fishponds. Furthermore, we are actively working on enhancing the fabrication process for flow sensors. For instance, we have demonstrated the ease of fabricating an airflow sensor by utilizing laser-induced graphene as the sensing element. To advance our sensor technology, we consider it essential to consistently integrate the latest technological advancements into our work.

Key words

MEMS, differential pressure sensor, flow measurement

Figures

Fig. 1  Photographs of (a) the developed differential pressure sensor, (b) the butterfly with the sensor chip, (c) the atmospheric pressure change sensor, (d) the compact airflow sensor.

Fig. 2  Photographs of (a) the developed Pitot-tube type waterflow sensor, (b) the sea turtle with the sensor, (c) the LIG based wind velocity sensor.