A biomimetic flow sensor based on asymmetric optical fiber sensory structure for marine sensing

With increasing awareness of the importance of the ocean, more research has been focused on the sensing of marine-related parameters. In this paper, a bio-inspired flow sensor endowed with virtues of corrosion resistance, anti-interference, portable design, ease of integration, and directional sensing ability has been presented to realize flow speed sensing in open space water such as the ocean. The sensor was realized by a flexible artificial cupula sealing one side of the s-tapered fiber encapsulated capillary as the hair cell sensory structure, and a 3D printing structure was fixed at the other end of the sensory structure as the artificial supporting cell. The transmission optical spectrums of the sensory fiber under a set of water flow velocities and four orthogonal directions were monitored to demonstrate the characteristics of the sensor. The intensity responses of corresponding peaks to evaluate flow velocity or direction were outlined respectively demonstrating the flow sensing ability for both velocity and direction. This biomimetic portable sensing structure has proven itself a promising candidate for flow sensing in marine environments.