Blind cave fish helps submarines see in the dark


A team from Singapore has been inspired by the Blind cave fish to develop a new way for submarines and other underwater vessels to "see", without the use of expensive cameras and sonar.

The Blind cave fish finds its way around using its highly developed lateral line system, which allows it to 'see' and 'hear' in its dark environment by monitoring changes in water pressure and flow around it.

Now a team from Singapore’s Nanyang Technological University has developed a set of tiny sensors to act as an artificial lateral line on submarines.

Using a combination of water pressure and computer vision technology, the sensory device is able to give users a 3-D image of nearby objects and map its surroundings. The possible applications of this fish-inspired sensor are enormous. The sensor can potentially replace the expensive 'eyes and ears' on Autonomous Underwater Vehicles (AUVs), submarines and boats that currently rely on cameras and sonars to gather information about the environment around them.

The revolutionary, low-powered sensor is unlike cameras which cannot see in dark or murky waters; or sonars whose sound waves pose harm to some marine animals.  

Associate Professor Miao Jianmin from the School of Mechanical and Aerospace Engineering, and his team of four have spent the last five years in collaboration with Singapore-MIT Alliance for Research and Technology (SMART) to develop micro-sensors that mimic the row of 'feelers' on both sides of the Blind cave fish’s body.

Associate Prof Miao said the line of sensors present on the fish’s body is the reason why it can sense objects around it and still travel at high speeds without colliding with any underwater obstacles.

"To mimic nature, our team created microscopic sensory pillars wrapped in hydrogel - a material which is similar to the natural neuromasts of the blind cave fish - into an array of two rows of five sensors," Prof Miao said.

"This array of micro-sensors will then allow AUVs to locate, identify, and classify obstacles and objects in water through water pressure and also to optimise its movement in water by sensing the water flow."

The new sensor array is much cheaper than sonars, which can detect faraway objects but not nearby objects and cost thousands of dollars.

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