6results about How to "Improve propulsion efficiency" patented technology

This invention provides an AUV multi-thrust propulsion system, comprising stabilizers, auxiliary rim thrusters, an AUV stern body, main rim thrusters, fairings, connecting discs, and a tail-mounted connecting frame. The main rim thrusters are fixedly connected to the rear end of the AUV stern body via the connecting discs. The fairings are positioned behind the blades of the main rim thrusters. The four auxiliary rim thrusters are uniformly fixed in a cross shape around the circumference of the AUV stern body. The four stabilizers are arranged in an X-shape on the stern body, staggered and evenly spaced with the four auxiliary rim thrusters. The advantages of this invention are increased maneuverability and controllability while reducing the complexity of the drive mechanism, saving stern space, and increasing the power, maneuverability, and system redundancy of the propulsion system by using multiple rim thrusters, thereby improving the safety, stability, controllability, and mission execution efficiency of the AUV in complex underwater environments.

This invention proposes a ducted propeller, comprising a tube body, a propeller body, and protruding units. At least one groove is formed on the inner wall of the tube body. The propeller body is disposed within the tube body and located at one end of the tube body. The groove is spirally arranged around the central axis of the tube body. Several protruding units are continuously and uniformly arranged within the groove along its spiral line. Adjacent protruding units are connected end-to-end. By forming a spiral-shaped groove on the inner wall of the tube body, the propeller wake is rectified. As the wake flows towards the outlet at the free end of the tube body, the circumferential velocity component of the wake gradually decreases under the action of the groove. This results in the circumferential velocity component at the wake outlet being significantly smaller than that at the wake inlet, thereby improving propulsion efficiency and reducing noise.

The present application relates to a method for cooperative control of a single propeller of an underwater snake robot based on reinforcement learning, comprising establishing a structural model of the underwater snake robot, constructing a motion control and decision model of the underwater snake robot, defining state space and action space, and integrating the multi-joint wave propulsion of the snake body and the thrust output of the tail propeller from the central pattern generator into the control decision framework, designing a composite reward function with path tracking error, heading deviation and propulsion efficiency as targets, training the motion control and decision model of the underwater snake robot based on a reinforcement learning algorithm, generating an optimal underwater snake robot cooperative control strategy to execute a multi-waypoint path tracking task of the underwater snake robot, so that the cooperative control strategy of the joint waveform parameters and the propeller thrust is autonomously learned without relying on an accurate hydrodynamic model, thereby realizing stable and high-precision path tracking of a hyper-redundant underwater snake robot under multi-path constraints including turning sections.

The utility model provides an underwater brushless motor. The underwater brushless motor comprises a stator assembly and a rotor assembly. The motor is characterized in that the stator assembly comprises a shell and a stator winding arranged on the inner side of the shell, and sealant wrapping the stator winding in a sealed mode is arranged in the shell; the rotor assembly comprises a rotor cylinder and a magnetic ring arranged on the side wall of the rotor cylinder in a sealed mode. A plurality of integrally formed paddles are arranged on the inner side of the rotor cylinder; at least two ceramic bearings are connected between the stator assembly and the rotor assembly, and the rotor assembly is rotatably connected with the stator assembly through the ceramic bearings. The motor adopts a non-central-spindle and non-support design, and the blades and the rotor cylinder are directly integrally formed, so that water flow and sundries can freely pass through the interior of the motor and are not easily wound by foreign matters such as silk threads, motor faults caused by jamming are reduced, and the system stability is improved.

The application discloses a drilling equipment for PCB production and belongs to the technical field of PCB production. The drilling equipment is characterized in that a dust absorption seat is arranged at the output end of a PCB drilling machine, a drill bit is connected to the output end of the PCB drilling machine, two cutting heads are arranged at the outer end of the drill bit, and the cutting heads comprise a plurality of crushing blades, a plurality of outer rotary cutting blades and an inner cutting blade. The inner cutting blade and the plurality of crushing blades are radially arranged at the outer end of the drill bit from inside to outside, and the end faces of the inner cutting blade and the plurality of crushing blades are axially contracted to the inside along the rotation direction. The outer rotary cutting blades are arranged between the inner cutting blade and the crushing blades and between the crushing blades, and the axial positions of the outer rotary cutting blades are located to the inside of the front ends of the inner cutting blade and the crushing blades in rotation and crushing. The drilling is performed in the mode of first cracking and crushing and then cutting. Compared with traditional grinding, the drilling equipment can greatly reduce frictional heat on one hand, improve the efficiency of drilling advancement on the other hand, avoid drill bit deformation caused by high temperature, and ensure the drilling precision.

An energy-saving guide wheel design method, through CFD analysis, selects an energy-saving guide wheel that meets the use of a real ship, selects the maximum energy-saving effect as the optimal method by energy-saving effect = ((PD_with energy-saving guide wheel / PD_naked ship)-1)*100%, determines the size and installation position of the energy-saving guide wheel, selects a good energy-saving effect scheme, and then determines it through testing, improves the propelling efficiency, reduces the energy loss of the propeller wake rotation, and the efficiency is improved by about 3-8%; the structure-matched energy-saving guide wheel can further reduce fuel consumption, and the comprehensive fuel-saving effect will exceed 2-5%, reducing the annual operating cost; reducing cavitation and vibration, optimizing water flow uniformity, reducing propeller cavitation corrosion and ship vibration, and prolonging equipment life; adapt to multiple working conditions, and the partially self-adaptive guide wheel can adjust the angle to adapt to different drafts or speeds.