The underwater rolling capability of 3-RPS rolling robot

The object of this work is to investigate the underwater rolling capability of 3-RPS rolling robot. The area transformation matrix is proposed to calculate water flow resistance of the robot under different postures. The rolling ability of the robot under the different water flows is discussed using the ZMP model with the various ground support areas. The initial and end gait of the robot in each support area are planned in order to ensure the roll feasibility of the robot. The roll feasibility study reveals that the greater the water velocity, the more likely the robot will roll when flowing downstream. The robot is in a stable state for the supporting areas A₁A₂A₃ and H₁H₂H₃ , no matter how the water flow speed changes. The robot rolls more easily for the support area D₂D₃F₃F₂ and F₂F₃H₃H₂ compared with the other support areas. The robot can hardly stay and rolls directly for the support area F₂F₃H₃H₂.