Scientists have designed a microrobot that can not only walk across water, but jump across it too. Inspired by the water strider, an insect that is able to travel across water with long strides and jumps without sinking in, the robot could be used to monitor the water quality of lakes, rivers and other bodies of water or in surveillance applications.
The water strider is able to skim across bodies of water by evenly distributing its light weight among its long legs. Its legs are covered with tiny hairs that create tiny air pockets that increase its buoyancy.
The team, led by Quinn Pan, have previously designed a robot inspired by the water strider that could walk across water but not perform the more difficult task of jumping because the downward force needed to jump would send the robot's legs through the water.
The team discovered that using super hydrophobic, or water-repellant materials, could aide the robot in being able to get the upward force necessary for a jump on the water. They used water repellant nickel foam to construct the robot's striding and jumping legs that creates buoyancy-boosting air pockets just like the strider's hair-covered legs.
The material worked. According to the American Chemical Society, the robot is able to "leap more than 5.5 inches, despite weighing as much as 1,100 water striders. In experiments, the robot could jump nearly 14 inches forward – more than twice its own length – leaving the water at about 3.6 miles per hour."
The research team says that the ability to leap will make the tiny robot more agile on the water as well as give it a way to avoid obstacles, like tree branches, floating on the water's surface.