The researcher has developed a strain sensor film with sensitivity 100 times higher than that of conventional strain sensors by forming wing-shaped movable structures in a grid pattern on a single film. Using the sensor film, the wind pressure distribution on the windshield of a vehicle can be measured.

Left: Configuration and working image of the sensor film (thickness: 50 µm) Right: Change in resistance of an ink developed by AIST to strain

A sensor capable of measuring wind pressure distribution at high density can be applied to various industries, including the development of low-fuel-consumption vehicle bodies. The change in electrical resistance (gauge factor) of conventional strain sensors is, however, too small to measure wind pressure on vehicles travelling on ordinary roads. A new sensitive sensor device that can be mounted on a curved surface needs to be developed.

The developed sensor has many movable structures that move in response to wind pressure and measure the wind pressure distribution by measuring the generated strains at multiple points. For high sensitivity measurement of strain, the researcher has developed an original conductive ink for a sensor and a strain sensor film with sensitivity 100-fold that of conventional strain sensors by printing these movable structures. He mounted the sensor film on the windshield of a vehicle and measured the wind pressure distribution at high density at a vehicle speed of 30 km per hour for the first time in the world.

The researcher will widely promote collaboration with companies to put the developed sensor film into practical use and will use the high-sensitivity strain sensor technology gained during the development process for other applications, such as analysis of body movement.