A team of researchers from Cornell University studied simple and common animals like frogs and crustaceans which can jump out of the water. These animals jump to either catch prey or to escape from the predators. The small size and predictable behavior of these animals make them an ideal study subject. While the team was studying these animals, they found that the key factor which allowed these animals to make a high jump was called ‘entrained water mass’. This is the amount of water which the animal brings with it when it leaves the water. The extra mass is usually a percentage of the total weight of the animal and the best jumpers have their ways to minimize it. This study enabled the researchers to build a robot which can jump out of the water like some fish.
These jumpers are often streamlined so that they can cut through the water smoothly. However, the robot built by the researchers to mimic this behavior was not that streamlined. The researchers picked a simple design with a hinge and a rubber band to give the jumping force. Their device was also unable to reach the heights which were achieved by the actual jumping animals. The author of the study, Sunghwan Jung said, “When we made and tested a robotic system similar to jumping animals, it didn’t jump as much as animals. Why? Our robot isn’t as streamlined and carries a lot of water with it. Imagine getting out of a swimming pool with a wet coat—you might not be able to walk due to the water weight.”
The researchers want to design the next model of their robot in such a way that it can move easily in water and can jump much higher as well. This research will help design more complex robots in future to breach in and out of the water. This research will be combined with another one on robots which spy on real animals and communication system to coordinate them. It is quite possible that in near future we will see fleets of small, jumping robots exploring the oceans.