The dynamic analysis of the complete integrated deep-ocean mining pilot system is carried out in this paper taking into account the interactions between each subsystem and ocean environment. The selfpropelled seafloor tracked miner is modeled as a single-body vehicle with 6 degrees of freedom which allows real-time simulation and can be applied for the dynamic simulation analysis of the complete integrated mining system. The interaction model between the tracked miner and soft cohesive seafloor soil is built based on the theory of terramechanics and considering the principal dimensions of the tracked miner and the mechanical characteristics of seabed soil. The pipe subsystem including the lift pipe, pumps, the buffer and the flexible hose are built as 3-D discrete element models which are divided into rigid elements linked by flexible connectors with 6-DOF stiffness coefficients. External forces such as the hydrodynamic force of seawater, the buoyancy forces acting at discrete locations on the flexible hose, and other forces are considered. The virtual prototypes of each subsystem are modeled and connected to form the complete integrated mining system and the interaction models between mining system and environment are developed, then the dynamic simulation analysis of the complete integrated deep-ocean mining pilot system is performed and discussed.
Interest in deep-ocean mining of manganese nodules and other metal deposits has developed as a result of rising metal prices, and out of concern for securing supplies of strategic and critical minerals. A typical and may be the most prospective deep-ocean mining system is an integration of self-propelled seafloor miner, miner-to-buffer flexible hose, buffer, pumps, lift pipe, mining ship and ocean transportation system. Due to the complexity of each subsystem and the coupled interaction between subsystem and ocean environment, the dynamic behavior analysis of the complete integrated mining system is difficult.