Mimicry of Sharp Turning Behaviours in a Robotic Fish

In nature, fish has astonishing swimming ability after thousands years of evolution. To realise fish-like swimming behaviours by a robotic system poses tremendous challenges, especially for the C-shape turning (CST). This requires fully understanding of fish biomechanics and the way to mimic it. Based on observations of fish swimming, this paper presents a new kinematics model to mimic the CST behaviour in a robotic fish with a 4-DOF (degrees of freedom) tail. The simulated and the real experiments are conducted to show the theoretic feasibility. Both behaviour analyses and hydrodynamics features between the robotic fish and the real fish are presented to show the performance.