Out of billions of people who have lived and are living in this world, only Jesus has been able to walk on water surface. The only other species to do so are the water-striders, the tiny bugs that can be found at the river. The next specie to pull off this impossible feat are robots that will be able to walk on water just like Water-striders.
A team of researchers and scientists from Seoul National University, Wuss Institute for Biologically Inspired Engineering at Harvard University and Harvard University John A. Paulson School of Engineering and Applied Sciences has created a robotic insect that is capable of walking on water and can leap from water like Water-striders.
Kyu Jin Cho, study’s co-senior author and Associate Professor in the Department of Mechanical and Aerospace Engineering and Director of the Biorobotics Laboratory at Seoul National University said, “Water’s surface needs to be pressed at the right speed for an adequate amount of time, up to a certain depth, in order to achieve jumping. The water strider is capable of doing all these things flawlessly.”
The water strider has legs with slightly curved tips and makes use of a rotational leg movement to help it take off from the surface of water. The team had to undergo extensive study of water striders to fully understand how they worked. They tested out the hypotheses via robotic prototypes. Robert Wood, Ph.D., co-author on study and a Wyss Institute Core Faculty member, the Charles River Professor of Engineering and Applied Sciences at the Harvard Paulson School, and founder of the Harvard Microrobotics Lab, said, “If you apply as much force as quickly as possible on water, the limbs will break through the surface and you won’t get anywhere.”
Study’s first co-author Je-Sung Koh, Ph.D. said, “Using its legs to push down on water, the natural water strider exerts the maximum amount of force just below the threshold that would break the water’s surface.”
By mimicking these movements, the robot insect is capable of exerting 16 times its body weight onto the water surface without breaking through to the other side. It has been built using a ‘torque reversal catapult mechanism’. ‘Pop-up’ manufacturing was used for creating a folded composite structure that would self-assemble. “The resulting robotic insects can achieve the same momentum and height that could be generated during a rapid jump on firm ground – but instead can do so on water – by spreading out the jumping thrust over a longer amount of time and in sustaining prolonged contact with the water’s surface,” said Wood.
“This international collaboration of biologists and roboticists has not only looked into nature to develop a novel, semi–aquatic bio-inspired robot that performs a new extreme form of robotic locomotion, but has also provided us with new insights on the natural mechanics at play in water striders,” said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D.
