Biomimetic Flow Sensor for Detecting Flow Rate and Direction as an Application for Maneuvering Autonomous Underwater Vehicle

Attaining the information of the hydrodynamic flow rate and direction is essential to the maneuvering of autonomous underwater vehicles (AUVs). This work presents a pillar-based flow sensor that measures hydrodynamic flow rate and direction. We propose a design that mimic the working principle of the neuromast, a ubiquitous organ in fishes that sense the water flow. By utilizing advances in piezo-resistive pressure sensors and 3D printing technology, sensor fabrication becomes fast and cost-effective, owing to reductions in labor and material cost for small batches. Measured results showed that the sensor sensitivity was 9.24 mV/m/s in the single mode and 20.3 mV/m/s in the differential mode. The resolution of the flow sensor was measured to be 4.93 mm/s in the water tunnel testing. The angular resolution of the flow sensor was 2.25°.