Near-surface locomotion and pumping

Fluid manipulations (e.g. pumping and locomotion) near the water surface are vital strategies employed by a wide range of aquatic and aerial organisms. This talk discusses recent fluid physics advances in understanding manipulations that utilize or benefit from the presence of the interface, with a focus on undulatory mechanisms for both propulsion and particle collection. Aquatic and semi-aquatic species such as apple snails and giant larvaceans use low-speed undulatory appendages to generate unidirectional flows for efficient particle collection. In addition to underwater strategies, we examine aerial locomotion near the surface, such as bat flight, which provides insights into aerodynamic control and surface interaction. Drawing inspiration from biological observations, we made efforts to develop multifunctional robots capable of both locomotion and debris collection at the water–air interface, demonstrating the potential of nature-inspired engineering for environmental applications.