Multi-rotor unmanned aerial vehicle for ocean inspection

Abstract

The invention discloses a multi-rotor unmanned aerial vehicle for ocean routing inspection, and belongs to the technical field of unmanned aerial vehicles, the multi-rotor unmanned aerial vehicle for ocean routing inspection comprises an unmanned aerial vehicle frame, a foldable rotor body, a console, a monitoring module, a sealed cabin, air cylinder type supporting legs, an expandable composite air bag, a closed floating plate and a double-piston pneumatic assembly, the sealed cabin is used for protecting internal parts, the air cylinder type supporting legs, the expandable composite air bag, the closed floating plate and the double-piston pneumatic assembly work cooperatively, during landing, air compression buffering is conducted, the floating plate is sequentially triggered to be unfolded, the air bag is sequentially triggered to be inflated, secondary buffering is conducted, huge buoyancy is provided, and safe landing and stable staying on the sea surface are achieved. In the storm environment, stability is enhanced by means of the storm-resistant stabilizing fins, rollover and transverse movement are prevented, the overall structure adapts to the severe ocean environment, inspection safety and efficiency are improved, and practical operation application is facilitated.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, and more specifically, to a multi-rotor marine inspection UAV. Background Technology

[0002] As a vital carrier of Earth's ecology and resources, the ocean's environmental monitoring, resource exploration, and safety inspections are crucial for maintaining ecological balance and ensuring the development of the marine economy. Traditional marine inspections rely heavily on ship patrols and manual fixed-point monitoring. These methods are limited by ship speed and the range of manual operations, resulting in low inspection efficiency, difficulty in achieving large-scale, high-frequency dynamic monitoring, and susceptibility to severe marine weather, leading to work interruptions or safety hazards. With the development of unmanned aerial vehicle (UAV) technology, multi-rotor UAVs, due to their advantages such as maneuverability, convenient take-off and landing, and ability to carry various monitoring equipment, are gradually being applied to the field of marine inspection. However, the unique characteristics of the marine environment present numerous challenges.

[0003] First, the high salt spray and high humidity environment of the ocean is highly corrosive to the structure and electronic components of drones. Ordinary metal structures are prone to rust, and electronic components, if not properly sealed, are susceptible to moisture and short circuits, leading to equipment failure and affecting the continuity of inspections. Second, after completing their missions, drones need to land on the sea surface for recovery. However, the sea surface is not a stable take-off and landing platform; waves and rough seas can easily cause drones to tilt, collide, or even capsize during landing. Existing drones lack effective sea surface buffering and stabilization mechanisms, making it difficult to ensure landing safety. Furthermore, existing drones lack sufficient stability when hovering on the sea surface, and are prone to swaying and drifting in wind and waves, which not only affects equipment safety but may also interrupt monitoring data collection or increase the difficulty of recovery. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-rotor marine inspection drone to solve the above-mentioned problems.

[0005] To achieve the above objectives, an embodiment of the present invention provides the following technical solution: A multi-rotor marine patrol drone includes a drone frame, with multiple evenly distributed foldable rotor bodies mounted on the outer end of the drone frame. A control console is fixedly mounted on the lower end of the drone frame, and a monitoring module is fixedly mounted on the front end of the control console. A sealed cabin is fixedly mounted on the lower end of the control console. Cylinder-type outriggers are fixedly mounted on the lower end of the foldable rotor bodies. An inflatable composite airbag is fixedly mounted inside the sealed cabin. A pair of symmetrically distributed enclosed floats are slidably mounted on the lower end of the sealed cabin. Dual-piston pneumatic assemblies are fixedly mounted on both the left and right ends of the sealed cabin, and the dual-piston pneumatic assemblies are connected between the cylinder-type outriggers and the inflatable composite airbag.

[0006] As a further improvement of the present invention, the cylinder-type outrigger includes a main cylinder body, an electromagnet is fixedly installed at the top of the main cylinder body, and an interference-fit composite piston is slidably installed on the inner side of the main cylinder body. An extension column is fixedly connected to the lower end of the composite piston, and a foot is fixedly connected to the lower end of the extension column. An air outlet is provided on the upper side wall of the main cylinder body. When the UAV lands on the sea surface, the contact between the foot and the sea surface, and the extension column pushes the composite piston in the main cylinder body to compress the gas, can achieve a preliminary buffering effect. The gas can be released into the dual-piston pneumatic assembly through the air outlet, and after the dual-piston pneumatic assembly drives a pair of closed floats to open, the gas is injected into the inflatable composite airbag. The expansion of the inflatable composite airbag achieves secondary buffering, which not only improves the safety of the UAV landing on the sea surface, but also allows the UAV to remain stable on the sea surface by relying on the buoyancy effect of the closed floats and the inflatable composite airbag.

[0007] As a further improvement of the present invention, the composite piston includes a piston one, a sealing ring fixedly connected to the lower end of the piston one, and a magnet fixedly connected to the upper end of the piston one. The sealing ring is used to protect the piston one and improve the sealing performance of the opening on the lower side of the main cylinder. The magnet can cooperate with an electromagnet to drive the composite piston to actively compress gas or reset by relying on the magnetic field of the electromagnet.

[0008] As a further improvement of the present invention, the dual-piston pneumatic assembly includes a bidirectional pneumatic actuator. A main pipe is fixedly connected to the center of the outer end of the bidirectional pneumatic actuator, and the end of the main pipe away from the bidirectional pneumatic actuator is connected to an air outlet. Branch pipes are fixedly connected to both the left and right ends of the bidirectional pneumatic actuator. The end of the branch pipe away from the bidirectional pneumatic actuator is connected to an inflatable composite airbag. One-way valves are installed on both the main pipe and the branch pipes. After the cylinder-type outriggers deliver compressed gas to the bidirectional pneumatic actuator through the main pipe, it first drives the deployment of a pair of closed floats, which not only makes room for the expansion of the inflatable composite airbag, but also increases the contact area with seawater to improve stability. Then, the compressed gas is delivered into the inflatable composite airbag through the branch pipes to promote its expansion.

[0009] As a further improvement of the present invention, the bidirectional pneumatic actuator includes a piston cylinder. A pair of interference-fit pistons are slidably installed inside the piston cylinder. An isolation sleeve is fixedly connected to one end of each pair of pistons close to each other. An L-shaped piston rod is fixedly connected to the end of each piston away from the isolation sleeve. Limiting rings are fixedly connected to the openings at both ends of the piston cylinder. A compression spring is fixedly connected between the pistons and the limiting rings. Air outlets corresponding to branch pipes are opened on both the left and right sides of the upper end of the piston cylinder. Compressed gas enters the piston cylinder through the branch pipe. At this time, the air outlets are blocked by the isolation sleeves. The gas mainly acts on the pair of isolation sleeves, causing them to move away from each other. The L-shaped piston rod drives the closed float to move and unfold. After the isolation sleeves move a certain distance, the air outlets are exposed. Then, the compressed gas enters the inflatable composite airbag through the branch pipe for inflation.

[0010] As a further improvement of the present invention, an air intake space is provided between the pair of isolation sleeves, and the air intake space is aligned with the main pipe, and the second air outlet is located at the end of the isolation sleeve near the second piston.

[0011] As a further improvement of the present invention, the enclosed float includes a movable plate, and a synchronization block is fixedly connected to both sides of the outer end of the movable plate. The L-shaped piston rod is fixedly connected to the synchronization block. Magnetic guide strips are fixedly connected to the ends of the pair of movable plates that are far apart from each other. Under normal conditions, the pair of movable plates seal the sealed chamber, which protects the inflatable composite airbag and prevents the UAV from being disturbed by airflow during flight. During landing, the compressed gas generated by the cylinder-type outriggers indirectly pushes the L-shaped piston rod to move, and then the movable plate is pulled to move and unfold through the synchronization block. This not only increases the contact area with seawater to improve buoyancy, but also ensures that the UAV lands on the sea surface in a relatively stable attitude.

[0012] As a further improvement of the present invention, a folding groove is provided at the lower end of the movable plate, and a matching anti-wave stabilizing fin is rotatably installed in the folding groove. Anti-rotation strips are fixedly installed on both the left and right sides of the lower end of the sealed chamber, and the anti-rotation strips are located below the anti-wave stabilizing fin. Multiple evenly distributed oblique punches are provided at the outer end of the movable plate in the area below the magnetic guide strip, and the oblique punches are connected to the folding groove. The lower end face of the magnetic guide strip is arc-shaped. When the sea surface is large, some seawater enters the oblique punches under the guidance of the magnetic guide strip and impacts the anti-wave fin at an angle. The stabilizing fins allow the drone to rotate relative to the moving plate, creating an anchoring effect that improves the stability of the drone frame on the sea surface. When the drone is propelled by wind and waves, it will naturally adjust to the attitude of least resistance, with the nose or tail facing the wave direction, significantly reducing roll and wave-facing area, further enhancing stability and avoiding the risk of being capsized by side waves. In calmer weather conditions, the anti-wind and wave stabilizing fins can automatically retract, reducing the difficulty of drone frame recovery. The magnetic guide strips can not only be used to guide seawater into the angled punch hole, but also provide magnetic guidance for the recovery action.

[0013] As a further improvement of the present invention, the anti-wave stabilizing fin includes fins, which are rotatably mounted in a folding groove via an elastic roller. An oblique anchor plate is fixedly connected to the lower side of the fin near the magnetic guide strip. Multiple evenly distributed flow channels are formed on the lower surface of the fin. The oblique anchor plate can further provide huge lateral resistance in the water, effectively suppressing the roll and drift of the UAV, thereby achieving the effect of anti-wave. The flow channels can guide some seawater, reducing the scouring of the fin.

[0014] As a further improvement of the present invention, the inflatable composite airbag includes an airbag body, a pair of inflation nozzles connected to branch pipes are installed on the side end of the airbag body, the outer surface of the airbag body is covered with an outer protective layer, and a plurality of arrayed buffer protrusions are fixedly connected to the lower end of the airbag body. The airbag body can expand rapidly after inflation, which not only achieves a cushioning effect, but also provides huge buoyancy. The outer protective layer is used to protect the airbag body to prevent rupture and air leakage. The buffer protrusions can not only further assist in improving the cushioning effect, but also control the posture of the inflatable composite airbag body.

[0015] Compared with the prior art, the advantages of this invention are: (0) The cylinder-type outriggers of the present invention can achieve initial cushioning through gas compression during landing; at the same time, the dual-piston pneumatic assembly can convert the compressed gas of the cylinder-type outriggers into the deployment power of the closed float, ensuring that the sea surface contact area is expanded before the expandable composite airbag is inflated; the expandable composite airbag and the closed float form a dual buoyancy support, which, together with the anti-wind and wave stabilizing fin structure, can provide lateral resistance in wind and waves, effectively suppressing rolling and avoiding equipment damage or capsizing when landing and staying on the sea surface.

[0016] (1) The anti-wave stabilizing fin of the present invention is installed in the folding groove of the moving plate by an elastic roll. It can be automatically deployed by the impact of seawater and reset by the torsion spring. It can adapt to the changes of wind and waves without additional power. The integrated structure of the magnetic guide strip and the moving plate can not only guide the seawater to help the stabilizing fin deploy, but also assist in the recovery and positioning. It can be deployed in wind and waves to improve the stability of the UAV on the sea surface, and at the same time facilitate active recovery. Attached Figure Description

[0017] Figure 1 This is a top-view structural diagram of the invention during flight; Figure 2 This is a schematic diagram of the structure of the invention from below during flight; Figure 3 This is a top-view structural diagram of the present invention during landing; Figure 4 This is a schematic diagram of the structure of the enclosed floating plate of the present invention after it has been unfolded. Figure 5 This is a cross-sectional view of the cylinder-type support leg of the present invention; Figure 6 This is a schematic diagram of the structure of the dual-piston pneumatic assembly of the present invention; Figure 7 This is a cross-sectional view of the bidirectional pneumatic actuator of the present invention; Figure 8 This is a schematic diagram of the structure of the enclosed floating plate of the present invention; Figure 9 This is a schematic diagram of the anti-wave stabilizing fin structure of the present invention; Figure 10 This is a schematic diagram of the structure of the inflatable composite airbag of the present invention.

[0018] The labels in the diagram represent: 1. UAV frame; 2. Foldable rotor body; 3. Monitoring module; 4. Cylinder-type outriggers; 41. Main cylinder; 42. Electromagnet; 43. Compound piston; 431. Piston 1; 432. Sealing ring; 433. Magnet; 44. Extension column; 45. Foot pad; 46. Air vent 1; 5. Control console; 6. Sealed chamber; 7. Enclosed float; 71. Moving plate; 72. Synchronization block; 73. Magnetic guide strip; 74. Angled punch; 75. Anti-wind and wave stabilizing fin; 751. Fin; 752. Elasticity 753. Reel; 754. Inclined Anchor Plate; 755. Guide Channel; 8. Double Piston Pneumatic Assembly; 81. Two-Way Pneumatic Actuator; 811. Piston Cylinder; 812. Piston Two; 813. Isolation Sleeve; 814. Air Outlet Two; 815. L-Shaped Piston Rod; 816. Compression Spring; 817. Limiting Ring; 82. Main Pipeline; 83. Branch Pipeline; 84. One-Way Valve; 9. Inflatable Composite Airbag; 91. Airbag Body; 92. Inflation Nozzle; 93. Outer Protective Layer; 94. Buffer Protrusion; 10. Anti-Rotation Strip. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] Example 1: Please see Figures 1-4 A multi-rotor marine patrol drone includes a drone frame 1, with multiple evenly distributed foldable rotor bodies 2 mounted on the outer end of the drone frame 1, a control console 5 fixedly mounted on the lower end of the drone frame 1, a monitoring module 3 fixedly mounted on the front end of the control console 5, a sealed cabin 6 fixedly mounted on the lower end of the control console 5, cylinder-type outriggers 4 fixedly mounted on the lower end of the foldable rotor bodies 2, an inflatable composite airbag 9 fixedly mounted on the inner side of the sealed cabin 6, a pair of symmetrically distributed closed floats 7 slidably mounted on the lower end of the sealed cabin 6, and dual-piston pneumatic assemblies 8 fixedly mounted on both the left and right ends of the sealed cabin 6, with the dual-piston pneumatic assemblies 8 connected between the cylinder-type outriggers 4 and the inflatable composite airbags 9.

[0021] The outer shell of console 5 is made of waterproof and corrosion-resistant ABS engineering plastic, with multiple layers of sealing strips and waterproof vent valves inside, achieving an IP67 waterproof rating to isolate it from seawater and salt spray. Console 5 integrates a microcontroller unit (MCU), a wireless communication module, a GPS positioning module, an attitude sensor, and a power management unit. All electrical components are industrial-grade waterproof encapsulated. Power is supplied by a lithium iron phosphate battery pack within the sealed compartment 6. This battery pack features high energy density, long cycle life, and good weather resistance, and is encased in a waterproof insulation layer. It is connected to the power management unit via wires to achieve power distribution and voltage stability. The core function of console 5 is to receive commands from the ground station or, according to a preset program, control the rotor motor speed via the MCU to adjust the flight attitude and trajectory. Simultaneously, it receives data from monitoring module 3 and uploads it to the ground station, combining attitude and positioning signals to ensure flight safety.

[0022] The sealed chamber 6 is made of stainless steel and has an internal partition structure. One side houses the lithium battery pack, and the other side houses the inflatable composite airbag 9. The lower end is equipped with a sliding guide rail that cooperates with the closed float 7. The guide rail is coated with seawater-resistant grease to reduce drag. Its function is to protect the internal components and airbag from seawater corrosion, and at the same time guide the movement of the float.

[0023] The monitoring module 3 is fixedly mounted on the front of the control console 5. Its casing is made of lightweight aluminum alloy with anodized finish for enhanced corrosion resistance. Internally, it integrates a high-definition industrial camera, an infrared thermal imager, and a water quality sensor. The camera lens is made of anti-fog and anti-salt spray optical glass with an anti-reflective and anti-corrosion coating to prevent seawater from affecting image formation. The monitoring module 3 is powered by the control console 5, and its operation is controlled by an MCU. It can switch shooting modes, adjust the detection range, or activate the sensor to collect data. The acquired images and parameters are transmitted to the control console 5 via a data cable and then uploaded to the ground station, enabling real-time monitoring of ocean conditions.

[0024] Please see Figure 5 The cylinder-type outrigger 4 includes a main cylinder 41, with an electromagnet 42 fixedly installed at the top of the main cylinder 41. An interference-fit composite piston 43 is slidably installed inside the main cylinder 41. An extension column 44 is fixedly connected to the lower end of the composite piston 43, and a foot pad 45 is fixedly connected to the lower end of the extension column 44. An air outlet 46 is provided on the upper side wall of the main cylinder 41. When the UAV lands on the sea surface, the foot pad 45 contacts the sea surface, and the extension column 44 pushes the composite piston 43 to compress the gas in the main cylinder 41, which can achieve a preliminary buffering effect. The gas can be released into the dual-piston pneumatic assembly 8 through the air outlet 46. After the dual-piston pneumatic assembly 8 drives a pair of closed floats 7 to open, the gas is injected into the inflatable composite airbag 9. The expansion of the inflatable composite airbag 9 achieves secondary buffering, which not only improves the safety of the UAV landing on the sea surface, but also allows the UAV to remain stable on the sea surface due to the buoyancy effect of the closed floats 7 and the inflatable composite airbag 9.

[0025] The compound piston 43 includes a piston 431, a sealing ring 432 fixedly connected to the lower end of the piston 431, and a magnet 433 fixedly connected to the upper end of the piston 431. The sealing ring 432 is used to protect the piston 431 and improve the sealing performance of the opening on the lower side of the main cylinder 41. The magnet 433 can cooperate with the electromagnet 42 to drive the compound piston 43 to actively compress gas or reset by relying on the magnetic field of the electromagnet 42.

[0026] The main cylinder body 41 is made of stainless steel, with precision machining of the cylinder walls to ensure accurate fit. The top electromagnet 42 is made of neodymium iron boron permanent magnet material, coated with epoxy resin for corrosion protection. The coil lead wire is connected to the control console 5 MCU via a waterproof connector, and the MCU controls the power supply. The piston 431 is made of wear-resistant cast iron, with a polytetrafluoroethylene coating to reduce drag and wear. The lower sealing ring 432 is made of fluororubber, which is oil-resistant, seawater-resistant, and provides a good seal. The upper magnet 433 is polarity-matched with the electromagnet 42, and when energized, it generates force to drive the piston to slide, achieving active compression or reset. The extension column 44 is made of high-strength aluminum alloy, and the lower foot 45 is made of elastic polyurethane, which is corrosion-resistant and provides cushioning to prevent damage. The upper air outlet 46 of the main cylinder body 41 is a stainless steel interface, connected to the double-piston pneumatic assembly 8 via a high-pressure resistant hose.

[0027] It should be noted that the main cylinder 41 is filled with compressed gas, and a barometer can be installed on the main cylinder 41 to link with the electromagnet 42. It can even be equipped with a small air pump to actively supply air, thereby ensuring that the compressed gas can be fully triggered.

[0028] Example 2: Please see Figures 6-7 The dual-piston pneumatic assembly 8 includes a bidirectional pneumatic actuator 81. A main pipe 82 is fixedly connected to the center of the outer end of the bidirectional pneumatic actuator 81, and the end of the main pipe 82 away from the bidirectional pneumatic actuator 81 is connected to the air outlet 46. Branch pipes 83 are fixedly connected to both the left and right ends of the bidirectional pneumatic actuator 81. The end of the branch pipe 83 away from the bidirectional pneumatic actuator 81 is connected to the inflatable composite airbag 9. One-way valves 84 are installed on both the main pipe 82 and the branch pipe 83. After the cylinder-type outrigger 4 delivers compressed gas to the bidirectional pneumatic actuator 81 through the main pipe 82, it first drives the deployment of a pair of closed floats 7, which not only makes room for the expansion of the inflatable composite airbag 9, but also increases the contact area with seawater to improve stability. Then, the compressed gas is delivered into the inflatable composite airbag 9 through the branch pipe 83 to cause it to expand.

[0029] The bidirectional pneumatic actuator 81 includes a piston cylinder 811. A pair of interference-fit pistons 812 are slidably mounted inside the piston cylinder 811. Each piston 812 has a spacer sleeve 813 fixedly connected to one end close to the other. An L-shaped piston rod 815 is fixedly connected to the end of each piston 812 away from the spacer sleeve 813. Limit rings 817 are fixedly connected to the openings at both ends of the piston cylinder 811. A compression spring 816 is fixedly connected between the piston 812 and the limit rings 817. The piston cylinder 811 has... A second air outlet 814 corresponding to the branch pipe 83 is provided. Compressed gas enters the piston cylinder 811 through the branch pipe 83. At this time, the second air outlet 814 is blocked by the isolation sleeve 813. The gas mainly acts on a pair of isolation sleeves 813, making them move away from each other. The L-shaped piston rod 815 drives the closed float 7 to move and unfold. When the isolation sleeve 813 moves a certain distance, the second air outlet 814 will be exposed. Then the compressed gas enters the inflatable composite airbag 9 through the branch pipe 83 for inflation.

[0030] An air intake space is provided between a pair of isolation sleeves 813, and the air intake space is aligned with the main pipe 82. The second air outlet 814 is located at the end of the isolation sleeve 813 near the second piston 812.

[0031] Piston cylinder 811 is made of stainless steel, piston 812 is made of wear-resistant aluminum alloy with a fluororubber sealing ring, isolation sleeve 813 is made of engineering plastic, L-shaped piston rod 815 is made of high-strength stainless steel, and limit ring 817 is used to limit piston 812 to prevent it from falling off. The edge of exhaust port 814 is chamfered to prevent turbulence. Main pipe 82 and branch pipe 83 are made of high-pressure resistant nylon tubing. One-way valve 84 has a brass body with a fluororubber valve core to ensure unidirectional gas flow and prevent backflow. The air inlet space between the two isolation sleeves 813 is aligned with the main pipe 82, and exhaust port 814 is located near piston 812 on the isolation sleeve 813. This ensures that the enclosed float 71 unfolds before the inflatable composite airbag 9 is inflated, sequentially triggering the buffer action to ensure a smooth landing of the UAV.

[0032] Example 3: Please see Figures 8-9The enclosed float 7 includes a movable plate 71. Both sides of the outer end of the movable plate 71 are fixedly connected to a synchronization block 72, and the L-shaped piston rod 815 is fixedly connected to the synchronization block 72. A pair of movable plates 71 are fixedly connected to magnetic guide strips 73 at opposite ends. Under normal conditions, the pair of movable plates 71 enclose the sealed chamber 6 to protect the inflatable composite airbag 9 and prevent the UAV from being disturbed by airflow during flight. During landing, the compressed gas generated by the cylinder-type outriggers 4 indirectly pushes the L-shaped piston rod 815 to move, which in turn pulls the movable plate 71 to move and unfold through the synchronization block 72. This not only increases the contact area with seawater to improve buoyancy, but also ensures that the UAV lands on the sea surface in a relatively stable attitude.

[0033] The lower end of the movable plate 71 has a folding groove, within which a matching anti-wave stabilizing fin 75 is rotatably installed. Anti-rotation strips 10 are fixedly installed on both the left and right sides of the lower end of the sealed chamber 6, and these strips are located below the anti-wave stabilizing fin 75. Multiple evenly distributed oblique perforations 74 are formed on the outer end of the movable plate 71 below the magnetic guide strip 73, and these perforations 74 are connected to the folding groove. The lower end face of the magnetic guide strip 73 is arc-shaped. When the sea surface is rough, some seawater enters the oblique perforations 74 under the guidance of the magnetic guide strip 73 and impacts the anti-wave stabilizing fin 75 obliquely. This allows the drone to rotate relative to the moving plate 71, creating an anchoring effect and improving the stability of the drone frame 1 on the sea surface. When the drone is pushed by wind and waves, it will naturally adjust to the attitude of least resistance, that is, the nose or tail of the drone faces the direction of the wave surge, significantly reducing the roll and the area facing the wave, further improving stability and avoiding the risk of being overturned by side waves. In addition, when the wind and waves are small, the anti-wind and wave stabilizing fin 75 can automatically retract, reducing the difficulty of recovering the drone frame 1. The magnetic guide bar 73 can not only be used to guide seawater into the oblique punch 74, but also provide magnetic guidance for the recovery action.

[0034] The anti-wave stabilizing fin 75 includes a fin 751, which is rotatably mounted in a folding groove via an elastic roller 752. An inclined anchor plate 753 is fixedly connected to the lower side of the fin 751 near the magnetic guide strip 73. Multiple evenly distributed flow channels 754 are formed on the lower surface of the fin 751. The inclined anchor plate 753 can further provide huge lateral resistance in the water, effectively suppressing the roll and drift of the UAV, thereby achieving the effect of anti-wave. The flow channels 754 can guide some seawater, reducing the scouring of the fin 751.

[0035] The movable plate 71 is made of foamed polypropylene buoyancy material, and is wrapped with glass fiber reinforced plastic to make it tough and impact resistant. The outer end synchronization block 72 is made of aluminum alloy and is connected to the L-shaped piston rod 815 by bolts to ensure synchronous movement. The magnetic guide bar 73 is made of neodymium iron boron permanent magnet material with an outer stainless steel anti-corrosion shell. The arc-shaped lower end face guides seawater and assists in recovery and positioning. The fins 751 of the anti-wave stabilizing fin 75 in the folding groove are made of spring steel, which has good elasticity and can be reset. It is installed through a stainless steel elastic roller 752. The torsion spring in the roller provides the reset force. The inclined anchor plate 753 is made of wear-resistant alloy, which provides lateral resistance to prevent rolling. The arc-shaped guide groove 754 on the lower surface reduces seawater scouring. The anti-rotation bar 10 at the lower end of the sealed chamber 6 restricts the rotation of the anti-wave stabilizing fin 75 under normal conditions to prevent interference during the flight of the UAV. After the closed float 71 moves and unfolds, the anti-wave stabilizing fin 75 leaves the limit range of the anti-rotation bar 10. At this time, it can unfold normally under the action of seawater. The inclined punch 74 of the moving plate 71 is inclined and penetrates, guiding seawater to drive the fins 751 to unfold and preventing seawater from entering the chamber.

[0036] Example 4: Please see Figure 10 The inflatable composite airbag 9 includes an airbag body 91. A pair of inflation nozzles 92 connected to branch pipes 83 are installed on the side of the airbag body 91. The outer surface of the airbag body 91 is covered with an outer protective layer 93. Multiple arrayed buffer protrusions 94 are fixedly connected to the lower end of the airbag body 91. The airbag body 91 can expand rapidly after inflation, which can not only achieve a cushioning effect, but also provide huge buoyancy. The outer protective layer 93 is used to protect the airbag body 91 to prevent rupture and air leakage. The buffer protrusions 94 can not only further assist in improving the cushioning effect, but also adjust the posture of the inflatable composite airbag body 91.

[0037] The airbag body 91 is made of high-strength nylon 66 fabric with a polyurethane coating, which is tear-resistant, corrosion-resistant, and has good airtightness. The side inflation nozzle 92 is made of brass with a high-pressure resistant sealing gasket and is connected to eight pipes 83 of the dual-piston pneumatic assembly via a hose. The outer protective layer 93 is an aramid fiber woven layer that protects the airbag from punctures. The lower cushioning protrusion 94 is made of hemispherical elastic nitrile rubber, which enhances cushioning and improves stability on the sea surface.

[0038] Working principle: During drone inspections, the ground station sends a start command to the control console 5 via the wireless communication module. The MCU controls the motors inside the foldable rotor body 2 to start, and the rotor blades rotate to generate lift, allowing the drone to ascend to a preset altitude. Simultaneously, the MCU activates the monitoring module 3, and the collected data is processed by the control console 5 and uploaded to the ground station. During the inspection, GPS positioning and attitude sensor feedback information is sent to the MCU, which adjusts the rotor speed to control the flight path and attitude, ensuring stable flight.

[0039] During landing, the MCU reduces the rotor speed based on positioning and altitude signals, allowing the drone to descend slowly. After the foot pad 45 contacts the sea surface, the reaction force pushes the composite piston 43 to compress gas for initial buffering. When the impact force is small, the MCU controls the electromagnet 42 to be energized, generating an attraction force on the composite piston 43, which further compresses it. The compressed gas enters the space between the two isolation sleeves 813 of the bidirectional pneumatic actuator 81 through the first air outlet 46 and the main pipe 82, pushing the second piston 812 and the L-shaped piston rod 815 to unfold the closed float 7, compressing the energy stored in the spring 816. After the closed float 71 unfolds, the isolation sleeve 813 moves to expose the second air outlet 814, and the gas is filled into the inflatable composite airbag 9 through the branch pipe 83 and the inflation nozzle 92. The airbag body 91 expands for secondary buffering and provides huge buoyancy, which, together with the closed float 71, allows the drone to float stably.

[0040] When the waves are high, seawater is guided by the magnetic guide bar 73 into the oblique punch 74, impacting the fins 751 to cause them to unfold. At the same time, the oblique anchor plate 753 enters the water to provide resistance and prevent rolling. When the waves decrease, the fins 751 are reset by the elastic reel 752. During recovery, the magnetic signal of the ground recovery device guides the magnetic guide bar 73 to achieve precise positioning. After the operator issues a reset command, the MCU controls the electromagnet 42 to generate a repulsive magnetic field to push the composite piston 43 to reset. The gas in the pneumatic system flows back, and the compression spring 816 pushes the closed float 71 and piston 812 to reset. The airbag body 91 deflates and retracts into the sealed chamber 6, completing the cycle.

[0041] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and not restrictive.

[0042] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A multi-rotor marine patrol drone, comprising a drone frame (1), wherein a plurality of evenly distributed foldable rotor bodies (2) are mounted on the outer end of the drone frame (1), characterized in that: The lower end of the UAV frame (1) is fixedly equipped with a console (5), the front end of the console (5) is fixedly equipped with a monitoring module (3), the lower end of the console (5) is fixedly equipped with a sealed cabin (6), the lower end of the foldable rotor body (2) is fixedly equipped with a cylinder-type outrigger (4), the inner side of the sealed cabin (6) is fixedly equipped with an inflatable composite airbag (9), the lower end of the sealed cabin (6) is slidably equipped with a pair of symmetrically distributed closed floats (7), the left and right ends of the sealed cabin (6) are both fixedly equipped with a double piston pneumatic assembly (8), and the double piston pneumatic assembly (8) is connected between the cylinder-type outrigger (4) and the inflatable composite airbag (9).

2. The multi-rotor marine inspection drone according to claim 1, characterized in that: The cylinder-type support leg (4) includes a main cylinder body (41), an electromagnet (42) is fixedly installed at the top of the main cylinder body (41), a compound piston (43) with interference fit is slidably installed on the inner side of the main cylinder body (41), an extension column (44) is fixedly connected to the lower end of the compound piston (43), a pad (45) is fixedly connected to the lower end of the extension column (44), and an air outlet (46) is opened on the upper side wall of the main cylinder body (41).

3. The multi-rotor marine inspection drone according to claim 2, characterized in that: The composite piston (43) includes a piston (431), a sealing ring (432) is fixedly connected to the lower end of the piston (431), and a magnet (433) is fixedly connected to the upper end of the piston (431).

4. The multi-rotor marine inspection drone according to claim 3, characterized in that: The dual-piston pneumatic assembly (8) includes a bidirectional pneumatic actuator (81). A main pipe (82) is fixedly connected to the center of the outer end of the bidirectional pneumatic actuator (81), and the end of the main pipe (82) away from the bidirectional pneumatic actuator (81) is connected to an air outlet (46). Both the left and right ends of the bidirectional pneumatic actuator (81) are fixedly connected to branch pipes (83). The end of the branch pipe (83) away from the bidirectional pneumatic actuator (81) is connected to an inflatable composite airbag (9). A one-way valve (84) is installed on both the main pipe (82) and the branch pipe (83).

5. A multi-rotor marine inspection drone according to claim 4, characterized in that: The bidirectional pneumatic actuator (81) includes a piston cylinder (811). A pair of interference-fit pistons (812) are slidably installed inside the piston cylinder (811). An isolation sleeve (813) is fixedly connected to one end of each piston (812) close to each other. An L-shaped piston rod (815) is fixedly connected to the end of the piston (812) away from the isolation sleeve (813). Limiting rings (817) are fixedly connected to the openings at both ends of the piston cylinder (811). A compression spring (816) is fixedly connected between the piston (812) and the limiting ring (817). Air outlets (814) corresponding to the branch pipe (83) are opened on both the left and right sides of the upper end of the piston cylinder (811).

6. A multi-rotor marine inspection drone according to claim 5, characterized in that: An air intake space is provided between the pair of isolation sleeves (813), and the air intake space is aligned with the main pipe (82). The second air outlet (814) is located at the end of the isolation sleeve (813) near the second piston (812).

7. A multi-rotor marine inspection drone according to claim 6, characterized in that: The closed floating plate (7) includes a movable plate (71), and a synchronization block (72) is fixedly connected to both sides of the outer end of the movable plate (71). The L-shaped piston rod (815) is fixedly connected to the synchronization block (72). A pair of movable plates (71) are fixedly connected to magnetic guide strips (73) at opposite ends.

8. A multi-rotor marine inspection drone according to claim 7, characterized in that: The lower end of the movable plate (71) is provided with a folding groove, and a matching anti-wave stabilizing fin (75) is rotatably installed in the folding groove. Anti-rotation strips (10) are fixedly installed on both the left and right sides of the lower end of the sealed chamber (6), and the anti-rotation strips (10) are located below the anti-wave stabilizing fin (75). The outer end of the movable plate (71) is provided with a plurality of evenly distributed oblique punches (74) in the area below the magnetic guide strip (73), and the oblique punches (74) are connected to the folding groove. The lower end face of the magnetic guide strip (73) is arc-shaped.

9. A multi-rotor marine inspection drone according to claim 1, characterized in that: The anti-wind and wave stabilizing fin (75) includes a fin (751), which is rotatably installed in a folding groove via an elastic roller (752). An inclined anchor plate (753) is fixedly connected to the lower side of the fin (751) near the magnetic guide strip (73). Multiple evenly distributed guide grooves (754) are opened on the lower surface of the fin (751).

10. A multi-rotor marine inspection drone according to claim 1, characterized in that: The inflatable composite airbag (9) includes an airbag body (91), a pair of inflation nozzles (92) connected to a branch pipe (83) are installed on the side of the airbag body (91), an outer protective layer (93) is covered on the outer surface of the airbag body (91), and a plurality of arrayed buffer protrusions (94) are fixedly connected to the lower end of the airbag body (91).

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