A groundbreaking development in soft robotics has led to the creation of a new class of insect-sized robots that can walk on water. These innovative machines are designed to detect pollutants, collect samples, and inspect flooded areas that are too hazardous for human access. The design draws inspiration primarily from the water strider, an insect well-known for its ability to navigate liquid surfaces.
The project is the work of researchers Ziyu Chen, Mengtian Yin, and Baoxing Xu from the University of Virginia in Charlottesville. Developing robots of this nature poses significant challenges. However, the team has devised a manufacturing process that overcomes many of the obstacles that have previously hindered progress in this field.
The novel fabrication method allows for the creation of lightweight, floating devices directly on the water”s surface. Traditionally, the thin, flexible films required for these soft robots needed to be produced on rigid surfaces like glass before being delicately removed and transferred onto the water, a process that often resulted in breakage.
This new approach avoids such complications by using the liquid itself as a “workspace.” Liquid polymer droplets can naturally spread into ultra-thin, uniform sheets across the water”s surface. With the aid of a precisely calibrated laser, the researchers can carve these sheets into intricate patterns, such as circles and stripes, with remarkable accuracy.
Utilizing this design method, the researchers have built prototypes of two insect-shaped robots. The first, named HydroBuckler, “walks” forward on the water using flexible legs, mimicking the movement of the water strider. The second prototype, HydroFlexor, propels itself across the surface using motions akin to fish fins.
Details of their innovative fabrication technique and the prototypes they have developed are detailed in the journal Science Advances.
