A Robotic Insect that has ability to Jump on Water

The researchers from Seoul National University and Harvard University, studied how water striders (Gerridae) jumped on water, to create a robot that could successfully launch itself from the surface of water.

When powered up for a jump, the spring releases, but slowly, dragging the ends of robot’s body and its 5cm insect-like legs downward with gradually increasing force to the limit the water surface will withstand.

The film also revealed the water strider sweeps its legs inward in order to maximise the time it can push against the surface, to boost the overall force. Water striders have legs with slightly curved tips that they use to press against the surface of water.

Mimicking these mechanics, the robotic insect built by the team can exert up to 16 times its own body weight on the water’s surface without breaking through, and can do so without complicated controls.

Researchers have designed and built a tiny robot that not only walks on water, but leaps free from its surface, talents that mimic the water strider.

Water striders, a semi-aquatic arthropod, are specially evolved for the task.

Nature remains the realm where scientists delve for inspiration for their newest robotic creations. Some animals – especially insects – can manage a water-based jump, but only through impressive feats of bio-engineering perfected by evolution. But this current project borrowed ideas from the water strider insect and much successful than the first one. For their robotic prototype they used a torque reversal catapult (TRC) mechanism.

After watching and analyzing the bugs, the team began to work on replicating the essential motion into the set up their robot.

At the moment, the strider-bot can only jump once, and cannot land upright.

How will these robots be used? We hope that this novel motility will be incorporated in the next-step research of small scale robots. The water strider lives on the surface of water relying on surface tension. It doesn’t take a degree in physics to understand that figuring out how to jump from water isn’t easy, and water striders are among the very few organisms that can do it. The insects are so light they ride high on the water’s surface, and they use the especially hairy feet on their middle set of legs to row their way across the water. Amazingly, the 1 centimeter tall robot can jump to the height of 14 cm.