A ducted propeller group and rotor unmanned aerial vehicle fusion cross-domain vehicle and navigation method

Abstract

The application provides a cross-domain vehicle combining a ducted propeller group and a rotor unmanned aerial vehicle and a navigation method, and belongs to the technical field of cross-domain vehicles.The cross-domain vehicle comprises six groups of circumferentially uniformly distributed ducted propellers, which comprise clockwise rotating ducted propellers and counterclockwise rotating ducted propellers; the clockwise rotating ducted propellers and the counterclockwise rotating ducted propellers are alternately arranged; the bottom of the ducted propeller is mounted on a circular base; the ducted propeller is connected with a cylindrical structure through a transverse connecting beam; a rotor unmanned aerial vehicle system is mounted on the cylindrical structure; and a flight control device and two groups of battery systems are mounted in the cylindrical structure.The vehicle integrates water surface navigation and air flight functions, realizes the operation requirements such as rapid and stable navigation on the water surface, smooth take-off and ascent into the air and safe landing on the water surface through fine regulation and control of the coordinated work of the ducted propeller group and the rotor unmanned aerial vehicle, realizes lightweight while ensuring the structural strength, and guarantees the stability and environmental adaptability of the vehicle.

Description

Technical Field

[0001] This invention belongs to the field of cross-domain vehicle technology, specifically relating to a cross-domain vehicle and navigation method that integrates a ducted propeller assembly and a rotary-wing unmanned aerial vehicle. Background Technology

[0002] With the surge in demand for marine development and emergency response, traditional marine operational equipment faces numerous limitations. Conventional marine monitoring vessels, thanks to their large hull space and endurance, can cruise at sea for extended periods to collect data. However, their large size and deep draft make it difficult to approach complex waters with shallows and reefs, and they cannot quickly reach the scene of sudden incidents. Consequently, they are inefficient in responding to tasks requiring rapid response, such as maritime emergency rescue and oil spill monitoring. While underwater unmanned vehicles (UUVs) can penetrate deep into the seabed to perform exploration and sampling operations, they are limited by underwater communication, making it difficult to transmit large amounts of data in real time. Furthermore, their short endurance and limited operating range prevent them from simultaneously performing surface and aerial operations. In contrast, rotary-wing UAVs, with their vertical takeoff and landing and agile maneuverability, can quickly take off to conduct wide-area patrols and disaster reconnaissance above the sea, promptly monitoring marine dynamics. They can also take off and land on the water with specific designs, delivering small supplies and deploying monitoring equipment to offshore platforms. Whether it's marine ecological environment monitoring, maritime emergency search and rescue, or offshore oil platform inspection, there is an urgent need for advanced equipment like rotary-wing drones that can overcome the limitations of the marine environment and achieve coordinated sea-air operations.

[0003] Currently, the market lacks a high-efficiency cross-domain UAV that can effectively reduce drag and resist capsizing, which significantly limits the efficiency and flexibility of related industries operating in complex environments. Existing multi-environment rotary-wing UAVs often employ a simple combination of ducted propellers and rotors, but this simple assembly has many drawbacks. On the one hand, when the connection between the duct and the fuselage is left untreated, airflow separation and vortices are induced, further increasing local drag. On the other hand, the aerodynamic interference generated when the ducted propeller and rotor systems coexist in close proximity creates significant parasitic drag. Furthermore, the tip and root vortices detached during rotor rotation intertwine, induce, collide, and even break down and reassemble with the complex vortex system generated by the duct in close proximity, significantly altering the local flow field structure and pressure distribution, generating unpredictable and strong induced drag. In addition, existing cross-domain UAVs fail to fully consider the differences between surface and air environments in their structural design, resulting in insufficient navigation performance and stability in different media. This prevents them from fully leveraging the advantages of ducted propellers and rotary-wing UAVs, making it difficult to achieve true multi-functional integration and efficient collaborative operation. Summary of the Invention

[0004] The purpose of this invention is to provide a cross-domain vehicle and navigation method that integrates a ducted propeller assembly and a rotary-wing UAV, enabling autonomous switching and stable attitude control in both water and air media.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A cross-domain vehicle integrating a ducted propeller assembly and a rotorcraft unmanned aerial vehicle (UAV) includes: six circumferentially evenly distributed ducted propellers, including clockwise rotating ducted propellers and counterclockwise rotating ducted propellers, which are arranged alternately. The bottom of each ducted propeller is mounted on a circular base. The ducted propellers are connected to a cylindrical structure via a transverse connecting beam. A rotorcraft UAV system is mounted on the cylindrical structure. A flight control device and two battery systems are installed inside the cylindrical structure.

[0007] Furthermore, the transverse connecting beam is made of a lightweight composite material with honeycomb topology optimization.

[0008] Furthermore, each of the six ducted propellers has a set of propellers installed inside it. The propellers are connected to brushless motors. The six brushless motors are arranged alternately as clockwise brushless motors and counterclockwise brushless motors.

[0009] Furthermore, the rotorcraft unmanned aerial vehicle system includes a central body, which is connected to a cylindrical structure at its lower part. The central body has unmanned aerial vehicle rotors, which are driven by a rotor engine and connected to the flight control device.

[0010] Furthermore, the rotor of the UAV adopts the Naca6412 airfoil.

[0011] Furthermore, the rotor engine is a waterproof engine, and the battery system is a waterproof battery system.

[0012] Furthermore, the transverse connecting beam adopts the Naca6412 airfoil.

[0013] Furthermore, the end of the transverse connecting beam is a fish-shaped rudder structure with a streamlined fish-shaped cross-section and an inclination angle of 15° to the vertical direction.

[0014] Furthermore, the transverse connecting beam has a through hole for placing electrical wiring equipment, and the two ends of the through hole are respectively connected to the ducted propeller and the cylindrical structure.

[0015] The present invention may also include:

[0016] A navigation method for a cross-domain vehicle integrating the above-mentioned ducted propeller assembly and rotary-wing UAV, the method comprising:

[0017] Upon exiting the water, the flight control computer dynamically adjusts the rotational speed of the six ducted propellers in real time, enabling differential rotation of the ducted propeller assembly in both clockwise and counterclockwise directions. This provides the vehicle with a horizontal component force perpendicular to the Z-axis, enhancing its resistance to wave-making drag and maintaining directional stability. Simultaneously, the UAV rotors activate synchronously, gradually increasing overall lift to compensate for the thrust loss of the ducted propellers near the water surface, thus assisting the vehicle in a smooth takeoff. Upon re-entry into the water, the UAV rotors and ducted propeller assembly work together to enable the vehicle to glide and land on the water surface, effectively mitigating the impact of water entry.

[0018] The beneficial effects of this invention are as follows:

[0019] This invention boasts superior flow guidance and drag reduction performance. The combination of Naca6412 airfoil and fish-shaped rudder structure in the transverse connecting beam avoids severe impacts and sudden flow separation at the rudder nose, reducing vortex disturbances generated by the ducted propeller and rotor. The gradually tapering tail design ensures smooth fluid exit from the vehicle surface, significantly suppressing the formation of large-scale, high-intensity low-pressure vortex zones at the tail, thus improving the vehicle's initial acceleration. Simultaneously, the fluid pressure gradient changes gradually, preventing drastic pressure changes during acceleration and deceleration, which helps reduce frictional drag. This optimized flow adhesion and guidance effect comprehensively achieves superior drag reduction performance while improving the vehicle's handling and propulsion efficiency.

[0020] This invention boasts exceptional stability and robust load-bearing capacity. The six-axis frame avoids power shortages caused by the failure of one or more ducted propellers, improving fault tolerance. Simultaneously, the frame and its internal through-holes provide space for differential rotation of the ducted propeller assembly to offset torque. Furthermore, when encountering strong winds or requiring rapid attitude correction, the symmetrical distribution of the six power units ensures more uniform power output and more precise torque control, achieving effective attitude adjustment with relatively small speed changes. This enables safe and stable navigation under conditions of high winds and waves, effectively guaranteeing operational continuity and data accuracy.

[0021] This invention employs advanced manufacturing processes and high reliability. It utilizes 3D printing technology to achieve highly complex geometric structures in a single molding process without additional costs, significantly reducing the number of parts and assembly steps, lowering assembly costs and failure risks, improving component performance and compactness, and significantly enhancing the overall structural strength and durability of the aircraft.

[0022] The precision integration of the complex streamlined crossframe and UAV support in this invention significantly optimizes the vehicle's hydrodynamic performance, greatly enhancing its adaptability and operational reliability in harsh environments. This not only effectively reduces equipment failure risks and maintenance costs but also ensures the long-term stable operation of the vehicle, providing a solid hardware foundation for performing cross-domain missions. Its excellent cross-medium maneuverability and environmental adaptability enable it to efficiently perform diverse tasks such as complex marine environmental monitoring, disaster emergency response, and precise delivery of deep-sea supplies, significantly improving operational efficiency and response speed in related fields. Attached Figure Description

[0023] Appendix Figure 1 This is a schematic diagram of the structure of the present invention;

[0024] Appendix Figure 2 This is a top view of the present invention;

[0025] Appendix Figure 3 This is a sectional view of the transverse connecting beam of the present invention;

[0026] Appendix Figure 4 This is a schematic diagram of the structure of the present invention without a rotary-wing unmanned aerial vehicle system.

[0027] In the attached diagram: 1. Ducted propeller; 2. Circular base; 3. Transverse connecting beam; 4. Fish-shaped rudder structure; 5. Through-hole; 6. Cylindrical structure; 7. UAV rotor; 8. Rotor engine. Detailed Implementation

[0028] The present invention will now be further described with reference to the accompanying drawings.

[0029] This invention provides a cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing unmanned aerial vehicle, as shown in the attached figure. Figure 1 , 2 As shown in Figure 4, it includes: ducted propeller assembly, connecting structure and rotor unmanned aerial vehicle system;

[0030] The ducted propeller assembly includes six vertically arranged ducted propellers 1 evenly distributed in a circle, providing continuous and reliable power to the vehicle, significantly improving the vehicle's micro-control capability and speed. It also has a circular base 2 underneath, which enhances the stability of surface operations. Each propeller and brushless motor are installed inside the assembly. The six brushless motors are divided into two groups that rotate counterclockwise and counterclockwise, with the counterclockwise rotation of the ducted propellers alternating. The counterclockwise rotation design cleverly eliminates the influence of torque. All six brushless motors are driven by a battery system located in the central cylindrical structure 6.

[0031] The connecting structure includes six transverse connecting beams 3 and a cylindrical structure 6. The transverse connecting beams 3 not only connect the ducted propeller 1 and the cylindrical structure 6, but also provide through holes 5 for powering the ducted propeller.

[0032] As attached Figure 3 As shown, the transverse connecting beam 3 adopts the Naca 6412 airfoil, and the end of the transverse connecting beam 3 is a fish-shaped rudder structure 4 with a fish-shaped streamlined cross section and an inclination angle of 15° with the vertical direction. While offsetting torque, it greatly reduces eddy current drag and friction drag, and improves speed and endurance. The cylindrical structure is equipped with flight control devices and two battery systems that power the six brushless motors and the rotor engine 8, respectively.

[0033] The rotorcraft unmanned aerial vehicle (UAV) system is located above the cylindrical structure 6 via a connecting structure. The central fuselage houses the UAV rotor 7, which also employs the Naca 6412 airfoil, exhibiting a high lift coefficient and stall delay characteristics, providing reliable lift and stability for the aircraft. The UAV rotor 7 is driven by an independent rotor engine 8, which is integrated into the central cylindrical structure 6 via a cable connection to a brushless motor. Connected to the flight control computer, it enables precise control of the ducted propeller and rotor speeds, improving maneuverability and supporting precise navigation or hovering at fixed points via preset programs or remote commands, facilitating agile operation in complex environments.

[0034] The six transverse connecting beams 3 are centrally symmetrical, made of lightweight composite material with honeycomb topology optimization, and integrally formed by 3D printing process.

[0035] The cylindrical structure 6 is an open structure, and is equipped with an IP78-rated rotor engine 8 and an independent battery pack inside.

[0036] The flight control device is installed inside the central cylindrical structure 6.

[0037] In this embodiment, the overall geometry of the aircraft exhibits high central symmetry, providing excellent flow guidance and drag reduction performance.

[0038] The main structure of the aircraft of this invention is integrally formed using 3D printing technology, integrating key components such as ducted propeller assembly, connecting truss, and rotor drone mounting base; ABS engineering plastic is selected as the printing material, which significantly reduces manufacturing costs and improves molding efficiency while ensuring structural strength, which is conducive to mass production; the internal structure is designed with a honeycomb configuration based on the principle of topology optimization, which effectively reduces the overall weight while meeting mechanical performance requirements, thereby improving the aircraft's maneuverability and energy utilization efficiency.

[0039] This invention's vehicle integrates surface navigation and aerial flight functions. Through precise control of the ducted propeller assembly and rotor working in tandem, it can achieve operational requirements such as rapid and stable surface navigation, smooth takeoff and ascent, and safe surface landing. The optimized shape design significantly improves hydrodynamic characteristics. Combined with 3D integral molding technology of honeycomb composite materials, it achieves lightweight while ensuring structural strength. The comprehensive application of design, materials, and control technologies fundamentally guarantees the vehicle's excellent stability, environmental adaptability, and efficient and reliable comprehensive mission execution capabilities in various operational scenarios.

[0040] This embodiment also provides a navigation method for a cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV. The method includes: the vehicle exhibits unique advantages during the transition between entering and exiting water; upon exiting the water, the flight control computer controls the rotation speed of the six ducted propellers 1 in real time, achieving differential rotation of the ducted propeller assembly in both clockwise and counterclockwise directions, thereby providing the vehicle with a horizontal component force perpendicular to the Z-axis, improving its ability to resist wave drag, and maintaining directional stability; simultaneously, the UAV rotor 7 starts synchronously, gradually increasing the overall lift to compensate for the negative impact of thrust loss of the ducted propellers 1 near the water surface, and assisting the vehicle in smoothly leaving the water and taking off; upon entering the water, the UAV rotor 7 and the ducted propeller assembly work together to enable the vehicle to glide and land on the water surface, which can effectively mitigate the impact effect of entering the water and is crucial for maintaining its structural integrity and ensuring operational safety.

[0041] Surface navigation mode operation:

[0042] When the vehicle performs surface navigation missions, the power of the brushless motors of the six ducted propeller sets is first reduced simultaneously. Then, the rotational speed of the ducted propellers is precisely adjusted according to the predetermined route, enabling the vehicle to adjust its direction of motion as expected and navigate quickly and stably on the water. During this process, the multi-source fusion navigation system monitors the vehicle's geographical location, heading, speed, attitude, and other key information in real time and transmits the data to the operating platform. Based on this real-time data and the preset mission plan, the operator remotely adjusts the engine power and steering mechanism according to the actual navigation conditions and mission requirements, dynamically adjusting the vehicle's operating parameters to ensure smooth and precise navigation. At the same time, the brushless motors built into the ducted propellers efficiently drive the generators to continuously charge the high-energy-density lithium battery packs, establishing a stable energy supply cycle and ensuring the vehicle's ability to operate continuously for extended periods. The battery management system monitors the battery pack status in real time, implements intelligent charging and discharging strategies, optimizes energy utilization efficiency, and extends battery life.

[0043] In-flight mode operation:

[0044] If the mission requires switching to aerial flight mode, the aircraft needs to adjust to a stable attitude through the steering mechanism. After stabilization, the power output of the ducted propeller is increased so that the aircraft can still accelerate upwards after the wing-ground effect disappears. At the same time, the operator conducts a comprehensive status assessment of the key equipment of the rotor-wing UAV system, including key indicators such as the structural integrity of the rotor and ducted propeller, motor output characteristics, and flight control system response performance. The health of the battery system and the quality of the communication link also need to be assessed to strictly determine whether the system meets the preset mission requirements. As the rotor speed continues to increase, the aircraft steadily leaves the water surface with the strong lift generated by the ducted propeller and rotor, and smoothly enters aerial flight. During the aerial flight phase, the operator can directly intervene in the control through a remote controller or activate the preset autopilot program. The latter strictly follows the flight path planning and mission parameters to implement high-precision closed-loop control of the aircraft's pitch attitude, yaw angle, and climb rate, thereby ensuring the efficient execution of aerial missions such as reconnaissance and surveillance and logistics delivery.

[0045] Coordinated control methods during takeoff:

[0046] To ensure a smooth takeoff and transition from water to air, this invention innovatively introduces a ducted propeller torque propulsion and rotor coordinated control mechanism. In the initial takeoff phase, the flight control computer first activates the six ducted propellers, causing clockwise and counterclockwise ducted propeller groups to rotate at different speeds. This provides the vehicle with a certain torque, effectively resisting lateral drift caused by water flow disturbances and precisely maintaining initial heading stability. Simultaneously, the UAV rotors are activated, and the flight control computer dynamically adjusts the rotor speed based on real-time sensor data, precisely increasing lift output. When lift exceeds gravity, the vehicle lifts off the water. Subsequently, the ducted propeller speeds are adjusted to be uniform to eliminate torque, and the flight control system dynamically optimizes the rotor speed distribution to ensure stable ascent until the predetermined altitude and attitude are reached, achieving a smooth transition from water to air.

[0047] Air-to-water landing phase operations:

[0048] Before the vehicle performs an air-to-water landing mission, the flight control computer first performs a comprehensive self-check, thoroughly verifying the critical status of the rotor system, waterproof coating sealing, and energy reserves to ensure that all systems are ready. During the landing, the flight control computer adjusts the rotor and ducted propeller speeds in real time to maintain a very low vertical speed and uniform descent to minimize the impact of water contact. When the altitude drops to 3 meters or below the water surface, the ducted propeller speed is strategically reduced to 50% of its rated value to enhance the air cushioning effect using the wing-ground effect. At the same time, the rotor enters an idling state to prevent attitude control loss and deviation. At the moment of water contact, the flight control computer immediately cuts off rotor power and adjusts the ducted propeller assembly speed and torque to propel it at a lower speed, thereby stabilizing the vehicle's course and ensuring its safe and smooth transition to water surface navigation, laying the foundation for subsequent missions or return.

[0049] Precautions during mode switching:

[0050] During the process, the flight control system must precisely coordinate the timing and intensity of the ducted propeller differential control and the rotor lift output. It must monitor attitude, altitude, and environmental disturbances in real time through multi-source sensors to dynamically offset wave drag, lateral drift, and water impact. It must strictly control the critical altitude for rotor start-stop to avoid attitude instability, structural overload, or component damage caused by power redundancy or loss. At the same time, it must strengthen energy management to ensure that the battery system maintains stable power supply during the high-power phase of mode switching, and adaptively adjust control parameters based on environmental perception data. Ultimately, it can achieve reliable operation with no sudden changes in power transition, no oscillations during attitude transition, and no over-limit structural loads.

[0051] Routine maintenance and upkeep:

[0052] To ensure the long-term stable operation and performance of the aircraft, the following maintenance and upkeep work must be carried out regularly:

[0053] As the core power system, the ducted propeller assembly and rotor system require regular disassembly and inspection of the blade structure integrity, and dynamic balancing calibration to prevent resonance during high-speed operation. The brushless motor needs to be cleaned of internal salt spray crystals and moisture, and the winding insulation performance and bearing wear condition need to be checked to ensure differential control response accuracy. The generator module should have its rectification efficiency and heat dissipation performance verified to prevent core aging due to prolonged charging and discharging. After each mission, the duct interior and rotor joint gaps must be thoroughly rinsed with fresh water to prevent aquatic organism adhesion and salt corrosion.

[0054] High-energy-density lithium battery packs require strict cycle life management. The battery management system should be used to trace the voltage balance of individual cells through historical data and replace cells with excessive capacity decay in a timely manner. A deep calibration should be performed every 50 charge-discharge cycles to eliminate capacity estimation errors. After operation in extreme environments, the integrity of the battery's water-proof coating should be checked to prevent water ingress that could lead to internal short circuits.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing unmanned aerial vehicle, characterized in that, include: Six ducted propellers (1) are evenly distributed around the circumference, including clockwise rotating ducted propellers and counterclockwise rotating ducted propellers. The clockwise rotating ducted propellers and the counterclockwise rotating ducted propellers are arranged alternately. The bottom of the ducted propellers (1) is mounted on a circular base (2). The ducted propellers (1) are connected to a cylindrical structure (6) through a transverse connecting beam (3). A rotary-wing unmanned aerial vehicle system is installed on the cylindrical structure (6). A flight control device and two battery systems are installed inside the cylindrical structure (6).

2. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 1, characterized in that, The transverse connecting beam (3) is made of lightweight composite material with honeycomb topology optimization.

3. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 1, characterized in that, Each of the six ducted propellers (1) has a set of propellers installed inside. The propellers are connected to brushless motors. The six brushless motors are divided into alternating clockwise brushless motors and counterclockwise brushless motors.

4. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 1, characterized in that, The rotorcraft unmanned aerial vehicle system includes a central body, which is connected to a cylindrical structure (6) at its lower part. The central body has unmanned aerial vehicle rotors (7), which are driven by rotor engines (8) and connected to the flight control device.

5. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 4, characterized in that, The rotor (7) of the UAV adopts the Naca6412 airfoil.

6. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 4, characterized in that, The rotor engine (8) is a waterproof engine, and the battery system is a waterproof battery system.

7. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 1, characterized in that, The transverse connecting beam (3) adopts the Naca6412 airfoil.

8. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV according to claim 7, characterized in that, The end of the transverse connecting beam (3) is a fish-shaped rudder structure (4), with a fish-shaped streamline cross-section and an inclination angle of 15° to the vertical direction.

9. The cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing UAV as described in claim 1, characterized in that, The transverse connecting beam (3) has a through hole (5) for placing electrical equipment inside. The two ends of the through hole (5) are connected to the ducted propeller (1) and the cylindrical structure (6), respectively.

10. A navigation method for a cross-domain vehicle integrating a ducted propeller assembly and a rotary-wing unmanned aerial vehicle as described in any one of claims 1-9, characterized in that, The method includes: When emerging from the water, the speed of the six ducted propellers (1) is adjusted in real time by the flight control computer to achieve differential rotation of the ducted propeller assembly in clockwise and counterclockwise directions, thereby giving the vehicle a horizontal component force perpendicular to the Z-axis, improving its ability to resist wave-making resistance and maintaining course stability. At the same time, the UAV rotor (7) starts synchronously, gradually increasing the overall lift, compensating for the negative impact of thrust loss of the ducted propellers (1) near the water surface, and helping the vehicle to smoothly leave the water and take off. When entering the water, the UAV rotor (7) and the ducted propeller (1) work together to enable the vehicle to glide and land on the water surface, effectively mitigating the impact effect of entering the water.

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