Abstract
Crickets and many other orthopteran insects can detect an impinging airflow using mechanosensory hairs located on their cerci. Inspired by these filiform mechanosensory hairs, a new symmetrical electrodes metal-core piezoelectric fiber (SMPF) was designed and fabricated as a building block for future airflow sensors. This novel type of airflow sensor was produced utilizing the extrusion method and high-temperature sintering. A metal core was basically located at the center of the fiber and surrounded by a hollow cylinder of ceramic material. Two thin metal films were spray-coated symmetrically on the surface of the fiber on opposite sides. After successful polarization, the two surface metal layers could be used as sensor electrodes. This way, a cantilevered SMPF was able to detect the strength and direction of an impinging airflow. A theoretical model of the SMPF airflow sensor was established and validated by the experimental results. The results further showed that the electric charge generated on the electrodes of a cantilevered SMPF grows exponentially with the airflow strength, and that it is proportional to the cosine of the airflow direction.
Get full access to this article
View all access options for this article.