Development of a turtle-like underwater vehicle using central pattern generator

This paper presents the construction and control of a turtle-like underwater vehicle, which uses four single axis oscillation flippers for swimming and attitude control. The maneuvers are realized by the composition of appropriate angular offset, vibration amplitude and vibration frequency of the flippers. After analyzing the actuated flippers' motion and the swimming gait, a CPG-based (central pattern generator) control architecture is introduced. Such a CPG model has several nice properties, i.e. limit cycle behavior, closed form solution, no discontinuities nor jerks performance. To estimate the utility and stability of the vehicle, experiments were also carried out in the Mochou Lake of Antarctic Zhongshan Station following the Chinese 29th Antarctic expedition. The experimental result proves that the vehicle is applicable to the underwater detection.