An interdisciplinary study of sea lion swimming: from biological studies to a robotic platform*

California sea lions  (Zalophus californianus) are highly maneuverable swimmers, capable of generating high thrust and agile turns. Their main propulsive surfaces, the foreflippers, feature multiple degrees of freedom, allowing their use for thrust production (through a downward, sweeping motion referred to as a “clap”), turning, stability and station holding (underwater “hovering”).   Additionally, their flexible bodies and amphibious nature make them an excellent platform to inspire the next generation of unmanned underwater vehicles.  Through multiple interdisciplinary studies of the fundamental systems of sea lion locomotion, we have designed and built a swimming robotic platform to further both our scientific and robotic goals.  These studies include: geometric and kinetic studies of both forward swimming and maneuvering,  Fore- and hindflipper studies, several robotic platforms to investigate the fluid mechanics and control of their thrust production, in situ measurements of swimming and porpoising, and many more.  These have all informed the robotic platform, SEAMOUR, that is capable independent of sea lion-inspired swimming.