Scientists craft strider-like robots that paddle and walk on water

Researchers at the University of Virginia have developed two insect-inspired soft robots, HydroFlexor and HydroBuckler, that can paddle and walk on water surfaces by mimicking the motions of aquatic insects like water striders. These tiny robots are powered by an overhead infrared heater that causes their layered polymer films to bend and move in response to heat, enabling controlled, repeatable motion including speed adjustment and directional changes. This breakthrough demonstrates the potential for miniature robots to perform tasks such as scouting flooded areas, monitoring pollutants, or collecting samples in environments challenging for humans. A key innovation enabling these robots is a novel fabrication technique called HydroSpread, pioneered by Professor Baoxing Xu. Unlike traditional methods that require transferring delicate films from rigid surfaces, HydroSpread allows ultrathin polymer films to be formed directly on water, providing a perfectly smooth platform and significantly reducing failure rates. This method enhances precision and yield, allowing for more complex and delicate designs in soft robotics. Beyond robotics, HydroSpread holds promise for producing thin,