Water Strider-Inspired, Responsive Jumping Robot Driven by Electro-Ribbon Actuator.

The water striders demonstrate exceptional agility in dynamic water-surface locomotion, enabling them to effectively avoid obstacles and evade predators. While current bioinspired jumping water strider robots predominantly rely on water pressure, which stores mechanical energy through elastic components to achieve transient high-power output, these robots exhibit delayed actuation responses (>500 ms) and substantial hydrodynamic disturbances during actuation. Here, a centimeter-scale jumping biomimetic water strider robot (mass: 0.21 g) that uses surface tension to jump on the water surface is presented. The robot employs an electro-ribbon actuator, enabling sub-second kinetics response, achieving vertical leaps of 128 mm with minimal surface perturbation. The gravitational potential energy of the robot at peak jumping height exceeds several orders of magnitude compared to the existing surface tension-dominated jumping robot. Additionally, the study also systematically studies the interaction mechanism of dynamic contact between the robot's driving legs and the liquid-air interface. This work provides new design principles for developing high-performance biomimetic systems capable of dynamic fluid surface interactions.