Soft Airflow Sensors With Artificial Hair Structures and Printed Ionogel Channels for Wind Gust Detection for Small Uncrewed Vehicles

This article describes the design of a soft airflow sensor capable of detecting the direction and the magnitude of airflow, taking advantage of an additive manufacturing technique for rapid prototyping. The sensor consists of an artificial hair structure and conductive ionogel channels. The artificial hair, made by 3-D printing, is designed to maximize the moments at the base caused by the airflows applied to the hair structure. The ionogel channels are directly printed on a flexible printed circuit board and then embedded in an elastomeric layer. A compact readout circuit is prepared to acquire the impedance information from the sensing channels. The sensor shows reliable and repeatable responses to unidirectional airflows ranging from 6 to 13 m/s. A clear relationship between the applied loads and the sensor outputs is observed. We also demonstrate the performance and the application of the proposed airflow sensor by installing it on a small uncrewed ground vehicle that achieves stable operation through the detection of atmospheric disturbances.