High-Sensitivity Whisker Sensor for Application in Bionic Electronic System.

Bionic electronic systems play a pivotal role in information acquisition and healthcare applications. Whisker sensors, inspired by the tactile hairs of mammals, are vital components to precisely perceive the environmental parameters in confined spaces, such as distance, morphology, and textures. Compared with traditional sensing technologies like radar and ultrasonic systems, whisker sensors offer advantages in device size, cost, power consumption, and environmental adaptability, making them especially significant for information acquisition, in particular, environments with a transparent medium. However, previous studies have reported challenges in enhancing the device's sensitivity and determining the direction of external forces. Inspired by the whisker of a rodent, a high-sensitivity whisker sensor (HSWS) is reported with a sensitivity of 62.6 kPa. This exceptional sensitivity is attributed to the design of a torque amplification structure, which transforms a external tiny mechanical stimulus into substantial material deformation in the sensitive layer. This deformation enhances the resistance changeable rate of the varistor, thereby improving the sensor's responsiveness to external stimuli and enabling precise calculation of the magnitude and direction of external forces. The whisker sensor exhibits excellent durability and stability after 5000 testing cycles. In addition, it can sense other environmental parameters such as wind speed and material surface texture. Finally, the whisker sensor is assembled into a bionic electronic mouse capable of distinguishing the traveling direction and distance to walls, assisting in autonomous navigation tasks within a maze. The proposed whisker sensor holds significant potential for the development of rescue robots, medical robots, and underwater robots.