Bioinspired Aquatic Microrobot Capable of Walking on Water Surface Like a Water Strider

TLDR

Walking on water is a human dream but natural for aquatic insects. The robot employs ten superhydrophobic legs, two miniature DC motors, and two actuating legs, and a numerical model of the leg–water interface explains its large supporting force. The study reports a microrobot that can stand, walk, and turn on water, with leg radius and contact angle influencing support, and its speed, agility, low cost, and ease of fabrication suggest applications in water quality and pollution monitoring.

Abstract

Walking on the water surface is a dream of humans, but it is exactly the way of life for some aquatic insects. In this study, a bionic aquatic microrobot capable of walking on the water surface like a water strider was reported. The novel water strider-like robot consisted of ten superhydrophobic supporting legs, two miniature dc motors, and two actuating legs. The microrobot could not only stand effortlessly but also walk and turn freely on the water surface, exhibiting an interesting motion characteristic. A numerical model describing the interface between the partially submerged leg and the air–water surface was established to fully understand the mechanism for the large supporting force of the leg. It was revealed that the radius and water contact angle of the legs significantly affect the supporting force. Because of its high speed, agility, low cost, and easy fabrication, this microrobot might have a potential application in water quality surveillance, water pollution monitoring, and so on.