Abstract
Crocodiles possess dome shaped pressure receptors called integumentary sensory organs (ISOs) on their skin, which assist crocodiles in sensing flows and locating the origin of the disturbances created by movements of other animals. The surface of each ISO is equipped with mechanoreceptors and free nerve endings, which together carry out the task of receiving mechanical stimulus. Inspired by ISOs of crocodiles, a dome with five piezoresistive pressure sensors mounted on its surface is constructed and its ability to detect an object moving in its vicinity is explored. A cylindrical rod is towed towards the dome shaped sensor and the patterns of outputs of five pressure sensors on the dome are investigated for drawing cues about the movement. The experimental results demonstrate that the dome is able to discern speed, distance and direction of the movement. The outcomes of this study serve as a building block for a prospective crocodile-inspired passive hydrodynamic sensing system which can enhance the sensing capabilities of autonomous underwater vehicles.