An underwater mining machine is designed to collect nodules from the surface of the seabed at a depth of 60-80 m. The technological process of underwater mining usually contains independent actions: separation from the mass, collection and transportation of minerals. The controlled actuator of the underwater mining machine does not guarantee simultaneous rotation and movement; however, it operates with high stability. The operating stability of such a drive is improved by introducing a rigid kinematic coupling between the feeding and cutting parts, when the solid mechanical characteristic of the cutting part is not less than that of the feeding part. The introduction of a rigid kinematic coupling allows the hydraulic turbine not to stop in case of an array with a different resistance. Such a condition is not satisfied if a hydraulic turbine drive is used as the main drive, but is guaranteed when a volumetric hydraulic drive is used. When the soft mechanical characteristic of the cutting part and the hard mechanical characteristic of the feeding part are combined, the hydraulic turbine stops (the displacement pump drive of the hydraulic drive rotates at a constant angular velocity). In order to stabilize the operating energy at maximum power, it is necessary to ensure the regulation of the hydraulic drive of the feed mechanism.
