Researchers have developed a small robotic version of an insect that moves forward using an extraordinary actuator.
According to a report from Saeed News, citing Mehr News Agency, the robot, called "WaterStrider," was created by a team of researchers at Washington State University. These researchers have also designed a smaller and simpler robot, inspired by insects, called the "Mini Bug."
The WaterStrider robot is 22 millimeters long and weighs 56 milligrams. Its body is primarily made of carbon fiber, and it uses four paddle-like legs to maintain surface tension and prevent sinking.
The most interesting feature of the robot is its shape-memory actuator, which moves its two arms or fins.
The actuator consists of two fine wires made from a nickel-titanium alloy. When heated, the wires contract, but once cooled, they return to their original, longer shape. When an electric current passes through the actuator, the wire heats up and contracts. When the current stops, the wires cool and revert to the stored shape.
By generating a pulsed electrical current, the state of the wires can be quickly changed, causing the connected arms to move. Using this method, the WaterStrider moves its arms 40 times per second and can travel at a speed of 6 millimeters per second across the water surface.
After adjustments were made, the actuator was able to lift a load 155 times heavier than its own weight. The researchers are now working on adding energy storage to the robot and are also exploring the development of other similar devices inspired by insects that can move both on and below the water’s surface.
