Modeling and Hydrodynamic Performance for a deep ocean manipulator based on Numerical Approach

An accurate dynamic model is important for both controller design and mission simulation, regardless of the control strategy employed. In this paper, a dynamic model for a 3500m underwater manipulator in flow disturbance is established based on Morison method. The technique provides a direct method for incorporating external environmental forces into the model. Applying the superposition principle, the hydraulic forces are decomposed into two parts, one is in static water condition and the other is in sea current condition. Through numerical calculation of hydrodynamics, the contribution of hydraulic resistance, buoyancy, sea steady flows and unsteady flows to manipulator’s dynamic are analyzed in sort. It offers a reliable basis for this 3-DOF manipulator controller design. The model derived is a closed form solution which can be utilized in modern model-based control schemes. The underwater test results verify the performance of controller in flow disturbance.