Development of an underwater oscillatory propulsion system using shape memory alloy

A fish-like propulsion system seems to be an efficient alternative to propellers in small underwater vehicles. This paper focuses on the design of a bionic structure of an oscillatory propulsion system, which originates from a sufficient analysis of the anatomical structure of a vivid fish, through application of artificial muscles (shape memory alloy) as its main driver. Meanwhile, we simplified the oscillatory propulsion system. Then, we gave a detailed dynamic analysis and established the quantitative relationship among parameters depending on the torque balance equation. Finally, the control system implementation for oscillatory motion was described. The results from the experiment indicate that the oscillatory propulsion system works well.