Multi-task load dual-mode take-off and landing unmanned aerial vehicle

Abstract

The invention relates to a multi-task-load dual-mode take-off and landing unmanned aerial vehicle, which belongs to the technical field of unmanned aerial vehicles, and comprises a multi-task-load unmanned aerial vehicle body, and a running take-off and landing device and a rocket boosting parachute recovery device which are mounted on the unmanned aerial vehicle body. The taxiing take-off and landing device and the rocket boosting parachute landing recovery device are replaced, the taxiing take-off and landing device comprises a front landing gear and a main landing gear, and the unmanned aerial vehicle is in a taxiing take-off and landing mode when the taxiing take-off and landing device is installed. The rocket boosting parachute recovery device comprises a rocket booster, a recovery parachute and a skid buffering and damping device, and when the rocket boosting parachute recovery device is installed on the unmanned aerial vehicle, the unmanned aerial vehicle is in a zero-length take-off and landing mode. A photoelectric platform is mounted at the bottom of the fuselage behind the nose landing gear; and a reconnaissance radar is mounted in the nose fairing above the nose landing gear. According to the invention, the arrangement requirements of different task loads and the layout and installation requirements of the take-off and landing device are considered, and the problem that the existing multi-task load small and medium-sized unmanned aerial vehicle is difficult to realize dual-mode take-off and landing is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of unmanned aerial vehicles, and specifically relates to a dual-mode take-off and landing unmanned aerial vehicle with a multi-mission payload, which has a rocket-assisted zero-length launch take-off and parachute recovery mode, and can also be equipped with a wheeled landing gear to adopt a taxiing take-off and landing mode. Background Art

[0002] Drones are widely used in military and civilian fields, and their take-off and landing methods vary. Common take-off methods include runway take-off, rocket-assisted zero-length launch, air launch, energy storage ejection and vertical take-off, etc., and landing methods include runway landing, parachute landing + skid shock absorption, parachute landing + airbag shock absorption, net collision / arresting recovery, shipboard / water recovery and vertical landing, etc. Under normal circumstances, drones can only use specific take-off and landing methods. For example, if a landing gear is installed, it can only take off and land on a runway, not by ejection. If a net collision recovery is used, it does not have the ability to take off and land vertically, etc., that is, the use scenario of the drone is limited by its take-off and landing method.

[0003] For medium and large fixed-wing drones, most of them use wheeled landing gear, which depends on the airport runway guarantee conditions to achieve autonomous taxiing takeoff and landing. This is more common in the models disclosed at home and abroad. For small and medium-sized drones with a take-off weight of tens of kilograms to hundreds of kilograms, the take-off and landing methods mentioned above are all adopted, and a single mode of take-off and landing recovery is generally adopted. For small or micro consumer drones with a take-off weight of less than tens of kilograms, a vertical take-off and landing design is usually adopted, and the general endurance time is less than half an hour. Some adopt a composite take-off and landing method of taxiing take-off and landing + vertical take-off and landing. For example, the Chinese invention patent with publication number CN112550752B discloses a multi-mode take-off and landing drone that can perform conventional taxiing take-off and landing, vertical take-off and landing, and catapult take-off. Its power source uses gunpowder. This take-off and landing mode is only suitable for small drones with a take-off weight of less than tens of kilograms.

[0004] Although it can be seen in public reports that some fixed-wing UAVs or general aviation aircraft, as well as small rotorcraft, equipped with landing gear are also equipped with parachutes. Typical parachute systems include CAPS and BRS, which are used for emergency recovery of UAVs in emergency situations. However, their main purpose is to protect high-value mission payloads or sensitive equipment on UAVs, as well as personnel on general aviation aircraft. During parachute emergency recovery, a certain degree of structural damage to the aircraft is allowed. Therefore, this compound landing mode belongs to the conventional non-destructive take-off and landing recovery method of UAVs.

[0005] Therefore, for small and medium-sized UAVs with a take-off weight of several hundred kilograms, a single take-off and landing mode is traditionally used. Each take-off and landing mode has its applicable environment and advantages and disadvantages. After the UAV determines the take-off and landing mode, its usage and application environment are limited by the take-off and landing mode. For example, the advantages of the taxiing take-off and landing mode are mature technology, low cost of use, fast mission response speed, and normalized flight, which is applicable to almost all UAVs. The disadvantages are that it relies on ground support resources such as airport runways and weather, poor maneuverability, and high flight control accuracy requirements. The advantages of rocket-assisted parachute recovery are good maneuverability, low dependence on site conditions, and can achieve launch and recovery in a field environment. The rocket-assisted launch device is small in weight and volume, and occupies less weight and space of the aircraft body. The disadvantage is that it involves the storage, transportation and use of pyrotechnics, and the recovery and landing accuracy is poor. The advantages of vertical take-off and landing are good maneuverability and low site requirements, and the disadvantage is that it is only applicable to small UAVs. Other take-off and landing modes such as energy storage ejection, collision net / arrest recovery also have advantages and disadvantages and applicable scope, and the technical versatility is not strong. Especially for small and medium-sized UAVs with multi-task loads, the UAVs need to be equipped with load equipment such as optoelectronic platforms and reconnaissance radars. On the one hand, it is hoped that the UAVs can integrate multiple take-off and landing recovery modes to adapt to the application of more take-off and landing environment scenarios; on the other hand, the multi-task load makes the installation space of the UAV limited, and it cannot affect the use of the load, so it is difficult to achieve the integration of multiple take-off and landing recovery devices.

[0006] Therefore, for small and medium-sized UAVs with multi-mission payloads, it is worth studying how to achieve multi-mode take-off, landing and recovery. Summary of the invention

[0007] Technical issues to be solved:

[0008] In order to avoid the shortcomings of the prior art, the present invention provides a dual-mode take-off and landing UAV with multi-mission payloads, which combines the rocket-assisted parachute recovery in the taxiing take-off and landing mode and the zero-length take-off and landing mode, and replaces the corresponding take-off and landing recovery mode according to the application scenario of the UAV, taking into account the layout requirements of different mission payloads and the layout and installation requirements of the take-off and landing equipment, thereby solving the problem that existing small and medium-sized UAVs with multi-mission payloads are difficult to achieve dual-mode take-off and landing.

[0009] The technical solution of the present invention is: a dual-mode take-off and landing UAV with a multi-mission load, comprising a UAV body with a multi-mission load, a taxiing take-off and landing device and a rocket-assisted parachute recovery device installed on the UAV body; the taxiing take-off and landing device and the rocket-assisted parachute recovery device are interchangeable, and when the UAV is equipped with the taxiing take-off and landing device, it is in a taxiing take-off and landing mode; when the UAV is equipped with the rocket-assisted parachute recovery device, it is in a zero-length take-off and landing mode;

[0010] The taxiing landing device comprises a front three-point wheeled landing gear, and the wheeled landing gear comprises a front landing gear and a main landing gear; the front landing gear is located at the bottom of the nose, and its upper end is detachably connected to the structural frame inside the nose, and the front landing gear can be folded and stored in the nose fairing; the main landing gear is provided with two, which are symmetrically installed on both sides of the bottom of the fuselage behind the wing relative to the front landing gear; an optoelectronic platform is installed at the bottom of the fuselage behind the front landing gear, and a reconnaissance radar is installed above the front landing gear in the nose fairing;

[0011] The rocket-assisted parachute recovery device includes a rocket booster, a recovery parachute and a skid buffer and shock-absorbing device; the rocket booster is installed at the tail end of the bottom of the fuselage and is used for zero-length launch and takeoff of the UAV; the recovery parachute is installed in the fuselage compartment behind the wing and is used for parachute recovery of the UAV; the skid buffer and shock-absorbing device is provided with two groups, which can be detachably and symmetrically installed at the bottom of the fuselage, located on both sides behind the optoelectronic platform, and are used for buffering and absorbing energy at the moment the UAV touches the ground.

[0012] A further technical solution of the present invention is: the front landing gear includes a front wheel, a front buffer strut, a steering servo, an anti-torsion arm assembly, a front lifting and retracting mechanism, a front lifting and retracting actuator and a front lifting bracket; the front lifting buffer strut is an oil-gas shock absorber, the top end of its shell is hinged to the front lifting bracket, and the bottom end of its telescopic inner tube is installed with the front wheel; the front lifting bracket is detachably fixedly connected to the first structural frame in the nose; the steering servo is installed on the outer side of the shell of the front lifting buffer strut to drive the steering of the front wheel; the anti-torsion arm assembly connects the steering servo and the front wheel to transmit steering power to the front wheel; the front lifting and retracting actuator is installed on the front lifting bracket, the telescopic end of which is hinged to the top end of the shell of the front lifting buffer strut, the fixed end of which is hinged to one end of the front lifting and retracting mechanism, and the other end of the front lifting and retracting mechanism is hinged to one side of the middle part of the shell of the front lifting buffer strut; the front lifting and retracting actuator is used to control the folding and unfolding of the front landing gear; the front lifting and retracting mechanism is foldable, and the unfolded state is used to support the front lifting buffer strut in a vertical state.

[0013] A further technical solution of the present invention is: the front lifting and retracting mechanism includes an upper arm and a lower arm; one end of the upper arm is hinged to one end of the lower arm, and the other end of the upper arm is hinged to the tail end of the fixed end of the front lifting and retracting actuator; the other end of the lower arm is hinged to one side of the shell of the front lifting buffer support.

[0014] A further technical solution of the present invention is: the anti-torsion arm assembly includes a mounting ring, an upper anti-torsion arm and a lower anti-torsion arm, the mounting ring is sleeved on the shell of the front buffer support and is coaxially rotatably connected thereto; the upper end of the lower anti-torsion arm is hinged to the outer side wall of the mounting ring, and the lower end of the lower anti-torsion arm is hinged to the upper end of the upper anti-torsion arm; the lower end of the upper anti-torsion arm is hinged to the front wheel; the rocker arm of the steering servo is hinged to the lower anti-torsion arm.

[0015] A further technical solution of the present invention is: the main landing gear includes a main engine wheel, a braking device, an oblique support arm and a main landing gear shock absorber; the oblique support arm serves as the main support of the main landing gear, and its upper end is detachably connected to the second structural frame in the fuselage, and its lower end is equipped with a main engine wheel; the braking device is installed on the inner side of the main engine wheel and is used for braking the main engine wheel; the main landing gear shock absorber is an oil-gas shock absorber, and its shell end is detachably connected to the second structural frame, and its telescopic end is detachably connected to the oblique support arm, and the main landing gear shock absorber is used for shock absorption and buffering of the main landing gear.

[0016] A further technical solution of the present invention is: the nose fairing includes two structures, one is a taxiing take-off and landing mode fairing, which is used for the taxiing take-off and landing mode; the other is a zero-length take-off and landing mode fairing, which is used for the zero-length take-off and landing mode; the two nose fairings have the same connection structure with the fuselage, the difference is that a switchable door is provided under the taxiing take-off and landing mode fairing, which is used to retract the front landing gear into the taxiing take-off and landing mode fairing.

[0017] A further technical solution of the present invention is: the skid buffering and shock absorbing device includes a shock absorber, a skid support arm, a skid rod and a skid retracting and extending mechanism; the front end of the skid rod is hinged to the fuselage, and its tail supporting end is fixedly connected to the lower end of the skid support arm, and the upper end of the skid support arm is detachably hinged to the bottom of the fuselage; the shock absorber is an oil-gas shock absorber, a shell end of which is hinged to the skid retracting and extending mechanism, and a telescopic end is hinged to the middle part of the skid support arm; the skid retracting and extending mechanism is installed in the fuselage, and is used to drive the skid support arm and the skid rod to flip and retract through the shock absorber.

[0018] A further technical solution of the present invention is: the slide retracting and extending mechanism includes a slide retracting and extending actuator and a slide rail, the slide rail is arc-shaped, and a through slide groove is provided along the center of the profile, and the two slide rails are opposite to each other and symmetrically fixed to the third structural frame and the fourth structural frame in the fuselage; the fixed end of the slide retracting and extending actuator is fixed in the fuselage, and the telescopic end thereof is horizontally hinged with a sliding shaft, and the two ends of the sliding shaft are respectively slidably installed in the slide grooves of the two slide rails; the top end of the shell of the shock absorber is hinged to the sliding shaft; under the action of the slide retracting and extending actuator, when the sliding shaft is located at the bottom end of the slide rail, the slide buffer shock absorbing device is in a landing buffer state, and when the sliding shaft is located at the top end of the slide rail, the slide buffer shock absorbing device is in a retracted state.

[0019] A further technical solution of the present invention is that the slide rail is an assembled structure, which is assembled by overlapping two sections of slide rails and is used for removing the slide shaft when the slide skid is retracted and the actuator is disassembled.

[0020] A further technical solution of the present invention is: the recovery parachute includes a parachute cabin, a parachute opening device and a main parachute, the parachute opening device and the main parachute are installed in the parachute cabin, and the parachute cabin is installed in the fuselage; the parachute opening device is used to drive the main parachute out of the cabin to open the parachute, and the main parachute is used to adjust the aerial recovery posture and aerodynamic deceleration of the drone.

[0021] Beneficial Effects

[0022] The beneficial effects of the present invention are as follows: the present invention designs a dual-mode take-off and landing device for small and medium-sized UAVs with multi-task loads, and through the design of a replaceable taxiing take-off and landing device and a rocket-assisted parachute recovery device, the multi-task load UAV can be compatible with two take-off and landing modes: taxiing take-off and landing and zero-length take-off and landing. The take-off and landing device can be replaced according to different combat use guarantee conditions and use requirements, which greatly improves the environmental adaptability of the combat application of the UAV system, and can achieve the complementary advantages of different take-off and landing modes, and avoid the application condition restrictions, shortcomings and disadvantages of different take-off and landing modes. At the same time, the present invention takes into account the working environment requirements of different mission loads, and the overall structure will not interfere with the work of the UAV mission load such as the optoelectronic platform, reconnaissance radar, etc.: the front landing gear with a folding recovery function is located below the taxiing take-off and landing mode fairing after recovery, and the reconnaissance radar is installed above it, which effectively utilizes the space, does not affect the reconnaissance radar, and does not block the optoelectronic platform located below the fuselage. The present invention not only meets the mission load working visibility requirements, but also meets the station and installation requirements of the take-off and landing device.

[0023] The take-off and landing devices of the two take-off and landing modes of the present invention can be assembled and disassembled by quick disassembly or by using universal tools, which can realize rapid replacement, and the operation process is clear and simple. A small number of operators are required, which can reduce the workload of service personnel, reduce the difficulty of service personnel training, shorten the training time, and save a lot of manpower, cost and time. In the rocket-assisted take-off and parachute recovery mode, the UAV system can take off and land in a field environment without an airport runway, with low requirements for logistics support and flexible and diverse usage. In the case of ground support conditions such as a runway, the UAV is equipped with a wheeled landing gear and switched to a taxiing take-off and landing mode. The UAV can use the taxiing take-off and landing mode to achieve normalized duty, reducing the cost of use and the workload of maintenance operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of a taxiing take-off and landing mode in an embodiment of the present invention;

[0025] Figure 2 Schematic diagram of zero-length takeoff and landing mode in an embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of the connection relationship of the wheeled landing gear in an embodiment of the present invention;

[0027] Figure 4Schematic diagram of the connection relationship of the skid buffer device in the embodiment of the present invention;

[0028] Figure 5 is a schematic diagram of the front landing gear retraction and extension in an embodiment of the present invention;

[0029] Figure 6 2 is a schematic diagram of launching and taking off in a zero-length takeoff and landing mode in an embodiment of the present invention;

[0030] Figure 7 The present invention is a flowchart of switching from a taxiing takeoff and landing mode to a zero-length takeoff and landing mode in an embodiment of the present invention, wherein (1) a diagram shows hoisting a taxiing takeoff and landing mode UAV onto a ground support vehicle; (2) a diagram shows the connection cables for separating the front landing gear and the main landing gear; (3) a diagram shows disassembling the taxiing takeoff and landing mode fairing, the front landing gear, and the main landing gear; (4) a diagram shows the skid buffer shock absorbing device, the recovery parachute, the zero-length takeoff and landing mode fairing, and the tools required for installation in preparation for the zero-length takeoff and landing mode; and (5) a diagram shows installing the skid buffer shock absorbing device, the recovery parachute, and the zero-length takeoff and landing mode fairing.

[0031] Description of reference numerals: 1. front landing gear, 101. front wheel, 102. front start buffer support, 103. upper anti-torsion arm, 104. lower anti-torsion arm, 105. upper support arm, 106. lower support arm, 107. front start bracket, 108. steering servo, 109. front start retracting actuator, 2. main landing gear, 201. main engine wheel, 202, oblique support arm, 203. main start shock absorber, 204. brake device, 3. taxiing take-off and landing mode fairing, 4. cabin door, 5. skid buffer shock absorbing device, 501. shock absorber, 502. skid support arm, 503. skid rod, 504. skid retracting actuator, 505. slide rail, 6. Recovery parachute, 7. Zero-length takeoff and landing mode fairing, 8. Front launch fulcrum, 9. Rear launch fulcrum, 10. Rocket booster, 11. Fuselage, 12. Wing, 13. Optoelectronic platform, 14. First structural frame, 15. Second structural frame, 16. Front landing gear fastening bolts, 17. Main launch shock absorber quick release pin, 18. Ground launch bracket, 19. Ground bracket vehicle, 20. Reconnaissance radar, 21. Sled rod mounting joint, 22. Oblique support arm mounting joint, 23. Oblique support arm quick release pin, 24. Main launch shock absorber mounting joint, 25. Sled support arm mounting joint, 26. Third structural frame, 27. Fourth structural frame, 28. Fifth structural frame. DETAILED DESCRIPTION

[0032] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0033] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0034] This embodiment provides a dual-mode take-off and landing UAV with multi-mission payloads, which can be equipped with a taxiing take-off and landing device and a rocket-assisted parachute recovery device, so it has two take-off and landing modes, namely the taxiing take-off and landing mode and the zero-length take-off and landing mode, which can meet the different take-off and landing environment requirements of the UAV. The overall layout of the scheme is compact, taking into account the layout requirements of different mission payloads such as optoelectronic platforms, reconnaissance radars, etc., as well as the layout and installation requirements of the take-off and landing device. It has the advantages of strong adaptability to the take-off and landing environment and simple and convenient operation, which can greatly expand the deployment range of the UAV system and reduce dependence on ground support conditions.

[0035] See also Figure 1 , 2 The embodiment provides a dual-mode take-off and landing UAV with a multi-mission payload, including a UAV body with a multi-mission payload, a taxiing take-off and landing device and a rocket-assisted parachute recovery device installed on the UAV body. When the taxiing take-off and landing device and the rocket-assisted parachute recovery device are replaced, the UAV is in a taxiing take-off and landing mode when the taxiing take-off and landing device is installed; when the UAV is installed with a rocket-assisted parachute recovery device, it is in a zero-length take-off and landing mode.

[0036] See also Figure 1 , 3 5. Taxiing take-off and landing are achieved through wheeled landing gear. The taxiing take-off and landing device includes a front landing gear 1 and a main landing gear 2. It is a front three-point wheeled landing gear used for take-off, landing, ground taxiing and parking of the UAV. The front landing gear 1 is located at the bottom of the nose and has steering and retracting functions. Its upper end is detachably connected to the first structural frame 14 inside the nose. The front landing gear 1 can be flipped forward and folded and stored in the nose fairing. There are two main landing gears 2, which are symmetrically installed on both sides of the bottom of the fuselage 11 behind the wing 12 relative to the front landing gear 1. An optoelectronic platform 13 is installed at the bottom of the fuselage 11 behind the front landing gear 1, and a reconnaissance radar 2 is installed above the front landing gear 1 in the nose fairing. The installation space of the reconnaissance radar 2 can also be replaced with satellite communication equipment as needed.

[0037] Specifically, the front landing gear 1 includes a front wheel 101, a front buffer strut 102, a steering servo 108, a mounting ring, an upper anti-torsion arm 103, a lower anti-torsion arm 104, an upper support arm 105, a lower support arm 106, a front retractable actuator 109 and a front support 107. The front support 107 is made of hard aluminum alloy material by machining, and is detachably fixedly connected to the first structural frame 14 in the nose through a fastening bolt 16. The front buffer strut 102 is an oil-gas shock absorber, including an outer cylinder shell and a telescopic inner cylinder coaxially installed in the shell and retractably and rotatably connected to the shell. The oil-gas shock absorber absorbs the kinetic energy of the bumps during the landing or gliding of the drone through the flow and friction of hydraulic oil, with high energy absorption efficiency, small structural volume and weight. The top of the outer cylinder shell of the front buffer strut 102 is hinged to the front support 107, and the bottom of the telescopic inner cylinder is installed with the front wheel 101 through a fork-shaped structure. Furthermore, the top of the fork-shaped structure is fixedly connected to the bottom of the telescopic inner tube of the front start buffer support 102, and the front wheel 101 is rotatably connected to the fork-shaped structure. The front wheel 101 is made of aluminum alloy spin-formed, with high specific strength and specific stiffness. A hole is made on the side of the front wheel 101 for installing the front start inflatable valve core. The front wheel tire is sleeved outside the front wheel and is a tubeless inflatable rubber tire.

[0038] The steering servo 108 is installed on the outer side of the housing of the front buffer support 102, and a supporting structure for installing the steering servo 108 is provided outside the housing of the front buffer support 102. The steering servo 108 is used to drive the front wheel 101 to steer. The steering servo 108 in this embodiment is a small electric servo, which adopts digital quantity control and plays a role in correcting deviation and steering during the ground taxiing of the front landing gear 1. The mounting ring is sleeved on the housing of the front buffer support 102 and is coaxially connected with it. The upper end of the lower anti-torsion arm 104 is hinged with the outer side wall of the mounting ring in a vertical plane, and the lower end of the lower anti-torsion arm 104 is hinged with the upper end of the upper anti-torsion arm 103 in a vertical plane. The lower end of the upper anti-torsion arm 103 is hinged with the fork-shaped structure for installing the front wheel 101 in a vertical plane. The rocker arm of the steering servo 108 is hinged with the lower anti-torsion arm 104 in a horizontal plane. The lower anti-torsion arm 104 is driven to rotate by the steering servo 108, which in turn drives the upper anti-torsion arm 103 to rotate, and then drives the fork-shaped structure to rotate to realize the rotation of the front wheel 101. In this embodiment, the upper anti-torsion arm 103 and the lower anti-torsion arm 104 are made of hard aluminum alloy material by machining. When sliding on the ground, the quick release pin between the upper and lower anti-torsion arms can be removed, and when the front wheel 101 is dragged arbitrarily, the reverse operation of the steering servo 108 is avoided.

[0039] The front lift-up and retraction actuator 109 is installed on the front lift-up bracket 107, and is used to control the retraction and extension of the front landing gear 1. The front lift-up and retraction actuator 109 adopts digital control and receives control instructions from the drone control system. The telescopic end of the front lift-up and retraction actuator 109 is hinged to the top of the shell of the front lift-up buffer support 102, and the tail end of its fixed end is hinged to one end of the upper support arm 105 in a vertical plane. The other end of the upper support arm 105 is hinged to one end of the lower support arm 106 in a vertical plane, and the other end of the lower support arm 106 is hinged to one side of the shell of the front lift-up buffer support 102 in a vertical plane. The upper arm 105 and the lower arm 106 are machined from a hard aluminum alloy material. When the front landing gear 1 is retracted, the upper arm 105 and the lower arm 106 can be folded and retracted; when the front landing gear 1 is lowered, the upper arm 105 and the lower arm 106 play a supporting role to prevent the retracting actuator 109 from being damaged by excessive axial force. The upper arm 105 and the lower arm 106 have a reverse self-locking function to prevent the front landing gear 1 from being accidentally retracted under the parking load when the retracting actuator 109 fails.

[0040] The front landing gear 1 in this embodiment adopts a modular, retractable and detachable design, which occupies a small space and can meet the requirements of installing the reconnaissance radar 2 and the front landing gear 1 in the nose fairing of the aircraft at the same time. After the front landing gear 1 is completed, it can be folded and retracted to ensure the forward field of view of the optoelectronic platform 13. Figure 3 The front landing gear fastening bolts 16 shown in the figure connect the front support 107 and the first structural frame 14, so that the mechanical connection between the front landing gear 1 and the fuselage 11 can be achieved, which is convenient for disassembly and assembly.

[0041] In order to match the retractable design of the front landing gear 1, the nose fairing is designed with two structures, one is the taxiing take-off and landing mode fairing 3, which is used in the taxiing take-off and landing mode. The other is the zero-length take-off and landing mode fairing 7, which is used in the zero-length take-off and landing mode. The two nose fairings have the same connection structure with the fuselage 11, and use the same fixing interface and fasteners. The difference is that a switchable door 4 is provided below the taxiing take-off and landing mode fairing 3, and the length of the taxiing take-off and landing mode fairing 3 is longer than the zero-length take-off and landing mode fairing 7, ensuring that there is enough space to retract the front landing gear into the taxiing take-off and landing mode fairing 3. The front landing gear 1 and the landing gear door 4 adopt a linkage design, which is realized by connecting rod linkage. No other actuator is required, and the door 4 can be opened and closed during the retraction and extension of the front landing gear 1.

[0042] The main landing gear 2 adopts a fixed oblique support arm form, which does not occupy the internal space of the fuselage. The main landing gear 2 is detachably connected to the main landing gear mounting joint on the fuselage through two quick release pins. The main landing gear 2 includes a main wheel 201, a brake device 204, an oblique support arm 202 and a main landing shock absorber 203. The main landing gear mounting joint includes an oblique support arm mounting joint 22 and a main landing shock absorber mounting joint 24. The oblique support arm mounting joint 22 and the main landing shock absorber mounting joint 24 are both fixed to the second structural frame 15 in the fuselage 11. The oblique support arm 202, as the main support of the main landing gear 2, is made of hard aluminum alloy machining, has high specific strength and specific stiffness, is used to withstand the impact load during the landing of the drone, and is used to support the drone when it is parked on the ground. The oblique support arm 202 is tilted outward from top to bottom, and its upper end is detachably connected to the oblique support arm mounting joint 22 through the oblique support arm quick release pin 23, and its lower end is rotatably mounted with the main wheel 201. The tire of the main wheel is sleeved outside the main wheel 201. The tire of the main wheel is a tubeless inflatable rubber tire, which is used to filter the bumps when the drone is gliding and absorb part of the energy of gliding and landing. The main wheel 201 is formed by aluminum alloy machining, with high strength and rigidity. The side of the wheel is made with holes for installing the main starting air valve core. The brake device 204 is installed on the inside of the main wheel 201 and is used for braking the main wheel 201. In this embodiment, the brake device 204 is a miniaturized all-electric brake device, which can receive control instructions, generate friction with the friction disc through the movement of the actuating element, and realize the braking and deceleration during the ground gliding of the drone. The left and right brake devices can also output different braking forces to realize the deviation correction function. The brake device 204 has the ability to measure wheel speed, and realizes the anti-lock braking function by controlling the output of the braking force. The main starting shock absorber 203 is an oil-gas shock absorber, which absorbs the kinetic energy of the bumps during the landing or gliding of the drone through the flow and friction of hydraulic oil, has high energy absorption efficiency, and has a small structural volume and weight. The housing end of the main start shock absorber 203 is detachably connected to the main start shock absorber mounting joint 24 via the main start shock absorber quick release pin 17 , and its telescopic end is detachably connected to the oblique support arm 202 . The main start shock absorber 203 is used for shock absorption and buffering of the main landing gear 2 .

[0043] In this embodiment, the front landing gear 1 and the main landing gear 2 of the taxiing and landing device are modularly designed and can be disassembled and assembled as a whole. The front landing gear 1 is mechanically connected to the fuselage 11 as a whole through 6 navigation bolts, and the main landing gear 2 is mechanically connected to the fuselage 11 as a whole through 2 quick-release pins. The advantages of the modular design are easy disassembly, storage and transportation, small disassembly workload, and no need for special tools.

[0044] See also Figure 2 , 46. Zero-length takeoff and landing is achieved by a rocket-assisted parachute recovery device, which includes a rocket booster 10, a recovery parachute 6 and a skid buffer shock-absorbing device 5. The rocket booster 10 is installed at the bottom tail of the fuselage 11 and is used for zero-length launch and takeoff of the UAV. In this embodiment, the rocket booster 10 is a small wide-temperature solid-charge rocket engine that can meet the power requirements of zero-length launch of UAVs under different temperature conditions in plains and plateaus. It is used to accelerate the UAV to a predetermined flight speed and push the UAV to a safe take-off height. The rocket booster 10 is a consumable and is installed before the UAV takes off. One is consumed per single sortie, and its gunpowder automatically falls off after burning out. The recovery parachute 6 is installed in the fuselage 11 cabin behind the wing 12 and is used for parachute recovery of the UAV. The recovery parachute 6 includes a parachute cabin, a parachute opening device and a main parachute. The parachute opening device and the main parachute are installed in the parachute cabin, and the parachute cabin is installed in the fuselage 11. The parachute opening device is used to drive the main parachute out of the cabin to open the parachute, and the main parachute is used to adjust the UAV's aerial recovery posture and aerodynamic deceleration. In this embodiment, the parachute opening device is a small solid gunpowder engine. After ignition, the recovery parachute is pulled out from the fuselage. A single sortie consumes one parachute opening device, which is installed and used before the UAV takes off. The recovery parachute 6 can realize the emergency recovery of the aircraft in the event of a landing gear failure or other emergency situations. The skid buffering and shock absorbing device 5 is provided with two groups, which can be detachably and symmetrically installed at the bottom of the fuselage 11, located on both sides behind the optoelectronic platform 13, and is used for buffering and absorbing energy when the UAV touches the ground.

[0045] Specifically, the skid buffer shock absorbing device includes a shock absorber 501, a skid support arm 502, a skid rod 503, a skid retracting and extending actuator 504, and a slide rail 505. Two sets of skid buffer shock absorbing device mounting joints are symmetrically arranged on both sides of the bottom of the fuselage 11, and each set of two front and rear mounting joints is used to install a set of skid buffer shock absorbing devices 5. Each set of skid buffer shock absorbing device mounting joints includes a skid rod mounting joint 21 and a skid support arm mounting joint 25. The skid rod mounting joint 21 is close to the nose and fixed to the fifth structure frame 28 in the fuselage. The fifth structure frame 28 is located behind the first structure frame 14. The skid support arm mounting joint 25 is located below the wing 12 and fixed between the third structure frame 26 and the fourth structure frame 27 in the fuselage 11. The front end of the sled rod 503 is hinged to the sled rod mounting joint 21 through a latch, and its rear support end is fixedly connected to the lower end of the sled support arm 502, and the upper end of the sled support arm 502 is detachably hinged to the sled support arm mounting joint 25 through a latch. The sled support arm 502 and the sled rod 503 are respectively made of hard aluminum alloy and high-strength steel machined and used to bear and transfer the load of the drone during the landing recovery process. The shock absorber 501 is an oil-gas shock absorber, which absorbs the kinetic energy of the drone parachute recovery impact of the ground through the flow and friction of hydraulic oil, has high energy absorption efficiency, and has a small structural volume and weight. The shell end of the shock absorber 501 is hinged to the telescopic end of the skid retraction actuator 504, and its telescopic end is hinged to the middle of the sled support arm 502 through a latch. The slide rail 505 is arc-shaped, and a through slide groove is provided along the center of the profile. The two slide rails 505 face each other and are symmetrically fixed to the third structure frame 26 and the fourth structure frame 27. The third structure frame 26 and the fourth structure frame 27 are parallel and perpendicular to the overall axis of the fuselage 11. The fixed end of the sled retracting actuator 504 is fixed to the fuselage 11 by mounting screws, and its telescopic end is horizontally hinged with a sliding shaft, and the two ends of the sliding shaft are respectively slidably installed in the slide grooves of the two slide rails 505. The top of the housing of the shock absorber 501 is hinged with the sliding shaft. When the drone touches the ground, the sled retracting actuator 504 is in a retracted state, and the sliding shaft of its telescopic end is located at the bottom of the slide rail 505. At this time, the sled buffer shock absorbing device 5 is in a landing buffer state. When the drone is flying, the sled retracting actuator 504 is in an extended state, and the sliding shaft of its telescopic end is located at the top of the slide rail 505. At this time, the sled buffer shock absorbing device 5 is in a flipped and retracted state. That is, the retractable actuator 504 serves as the retractable power source for the skid buffer and shock absorbing device 5. When the retractable actuator 504 is extended, the skid buffer and shock absorbing device 5 can be retracted on both sides of the fuselage, thereby reducing the aerodynamic resistance during flight and improving the flight performance. Before parachute recovery, the retractable actuator 504 is retracted to lower the skid buffer and shock absorbing device 5 to absorb the impact load during the landing recovery process.

[0046] In order to facilitate the disassembly of the sled retracting and releasing actuator 504, the slide rail 505 is an assembled structure, which is assembled by overlapping two sections of the slide rail, and the specific splicing position is set near the top of the slide rail 505. When disassembling the sled retracting and releasing actuator 504, as long as the splicing part at the top of the slide rail 505 is removed, the sliding shaft can be easily taken out from the slide slot. When disassembling, first remove the connecting pins between the sled support arm 502 and the fuselage 11, the sled rod 503 and the fuselage 11, and the sled rod 503 and the shock absorber 501, then the sled support arm 502 and the sled rod 503 can be removed; then, remove the fixing bolts between the bottom end of the sled retracting and releasing actuator 504 and the fuselage, and the removable splicing part at the top of the slide rail 505, and the shock absorber 501 and the sled retracting and releasing actuator 504 can be taken out from the inside of the slide slot.

[0047] In the zero-length takeoff and landing mode, the UAV needs to cooperate with the ground launch bracket 18 for launch. A front launch fulcrum 8 is provided at the bottom of the UAV fuselage, just below the first structural frame 14, and a rear launch fulcrum 9 is provided at the tail end support of the sled rod 503. The UAV is placed on the ground launch bracket 18 through the front and rear launch fulcrums, and the front and rear launch fulcrums play the role of supporting the UAV. Of course, the ground launch bracket 18 is Figure 6 What is shown is only an example of a ground launch bracket, and other ground launch bracket solutions can also be used.

[0048] The UAV of the present invention adjusts the installation position of the airborne equipment through the overall layout design of the whole machine, ensuring that the center of gravity of the whole machine in different take-off and landing modes meets the requirements of static stability margin. The overall layout of the taxiing take-off and landing device, the rocket-assisted parachute recovery device and the mission payload meets the weight and center of gravity changes caused by the take-off and landing mode conversion, and at the same time meets the weight balance and control of the two take-off and landing modes. The present invention adopts a mechanical interface and electrical interface design that simultaneously meets the requirements of the taxiing take-off and landing device and the rocket-assisted parachute recovery device, realizing functions such as structural installation, power supply and communication.

[0049] The taxiing take-off and landing device and the rocket-assisted parachute recovery device of the present invention both adopt a modular and detachable design, are connected to the body structure by bolts or quick-release pins, etc., and can be conveniently disassembled and assembled with the help of tools to achieve the conversion of the UAV take-off and landing mode. The following is an example of switching from the taxiing take-off and landing mode to the zero-length take-off and landing mode to illustrate.

[0050] See also Figure 7 The process of switching from the rolling takeoff and landing mode to the zero-length takeoff and landing mode includes the following steps:

[0051] Step 1, such as Figure 7 As shown in Figure (1), a ground support vehicle 19 is placed on a hard horizontal ground, the ground support vehicle 19 is fixed by the wheel brakes of the support vehicle, and the UAV in the taxiing take-off and landing mode is lifted onto the ground support vehicle 19 using a crane equipped with the UAV system.

[0052] Step 2, such as Figure 7 As shown in Figure (2), unscrew the connecting cable connectors of the retracting and extending actuator 109 of the front landing gear 1, the steering servo 108 and the brake device 204 of the main landing gear 2 to separate the onboard cables.

[0053] Step 3, such as Figure 7 As shown in Figure (3), first use a screwdriver to remove the UAV taxiing takeoff and landing mode fairing 3, then use a wrench to unscrew the connecting bolts 16 between the front landing gear 1 and the UAV, remove the front landing gear 1, and finally pull out the main take-off shock absorber quick release pin 17 and the inclined support arm quick release pin 23 connecting the main landing gear 2 and the fuselage 11, remove the main landing gear 2, and place the front and main landing gears in a special packaging box.

[0054] Step 4, such as Figure 7 As shown in Figure (4), the skid cushioning and shock absorbing device 5, the recovery parachute 6 and the zero-length take-off and landing mode fairing 7 are prepared, and the general tools required for installation are prepared.

[0055] Step 5, such as Figure 7 As shown in Figure (5), the sliding shaft connected with the telescopic end of the skid retracting actuator 504 and the housing end of the shock absorber 501 is placed in the slide groove of the slide rail 505, and the fixed end of the skid retracting actuator 504 is fixed to the corresponding position in the body with a screw, and the corresponding pins are inserted to connect the skid arm 502 and the skid rod 503 to the skid arm mounting joint 25 and the skid rod mounting joint 21 respectively, so that the skid arm 502 is connected to the telescopic end of the shock absorber 501. Use a screwdriver to install and fix the zero-length takeoff and landing mode fairing 7.

[0056] Step 6: Before the UAV takes off, the rocket booster 10 and its ignition cable are installed and docked with the UAV.

[0057] The above steps complete the conversion from the taxiing take-off and landing mode to the zero-length take-off and landing mode. When it is necessary to convert from the zero-length take-off and landing mode to the taxiing take-off and landing mode, just perform the operations in reverse order.

[0058] It should be noted that Figure 7 A ground support vehicle 19 is used as an example for illustration, and different UAV support solutions can also be used to achieve the replacement.

[0059] In other embodiments, the UAV may be lifted first, and then the take-off and landing device may be replaced to achieve the change of take-off and landing mode.

[0060] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A dual-mode take-off and landing UAV with a multi-mission payload, comprising a UAV body with a multi-mission payload, characterized in that: It also includes a taxiing take-off and landing device and a rocket-assisted parachute recovery device installed on the UAV body. When the taxiing take-off and landing device and the rocket-assisted parachute recovery device are replaced, the UAV is in a taxiing take-off and landing mode when the taxiing take-off and landing device is installed; when the UAV is installed with the rocket-assisted parachute recovery device, it is in a zero-length take-off and landing mode; The taxiing landing device comprises a front three-point wheeled landing gear, and the wheeled landing gear comprises a front landing gear and a main landing gear; the front landing gear is located at the bottom of the nose, and its upper end is detachably connected to the structural frame inside the nose, and the front landing gear can be folded and stored in the nose fairing; the main landing gear is provided with two, which are symmetrically installed on both sides of the bottom of the fuselage behind the wing relative to the front landing gear; an optoelectronic platform is installed at the bottom of the fuselage behind the front landing gear, and a reconnaissance radar is installed above the front landing gear in the nose fairing; The rocket-assisted parachute recovery device includes a rocket booster, a recovery parachute and a skid buffer and shock-absorbing device; the rocket booster is installed at the tail end of the bottom of the fuselage and is used for zero-length launch and takeoff of the UAV; the recovery parachute is installed in the fuselage compartment behind the wing and is used for parachute recovery of the UAV; the skid buffer and shock-absorbing device is provided with two groups, which can be detachably and symmetrically installed at the bottom of the fuselage, located on both sides behind the optoelectronic platform, and are used for buffering and absorbing energy at the moment the UAV touches the ground.

2. The dual-mode take-off and landing UAV with multi-mission payload according to claim 1, characterized in that: The front landing gear includes a front wheel, a front buffer strut, a steering servo, an anti-torsion arm assembly, a front lifting and retracting mechanism, a front lifting and retracting actuator and a front lifting bracket; the front lifting buffer strut is an oil-gas shock absorber, the top end of its shell is hinged to the front lifting bracket, and the bottom end of its telescopic inner tube is equipped with a front wheel; the front lifting bracket is detachably fixedly connected to the first structural frame in the nose; the steering servo is installed on the outer side of the shell of the front lifting buffer strut, and is used to drive the steering of the front wheel; the anti-torsion arm assembly connects the steering servo and the front wheel, and is used to transmit steering power to the front wheel; the front lifting and retracting actuator is installed on the front lifting bracket, the telescopic end of which is hinged to the top end of the shell of the front lifting buffer strut, the fixed end of which is hinged to one end of the front lifting and retracting mechanism, and the other end of the front lifting and retracting mechanism is hinged to one side of the middle part of the shell of the front lifting buffer strut; the front lifting and retracting actuator is used to control the folding and unfolding of the front landing gear; the front lifting and retracting mechanism is foldable, and the unfolded state is used to support the front lifting buffer strut in a vertical state.

3. The dual-mode take-off and landing UAV with multi-mission payload according to claim 2, characterized in that: The front lifting and retracting mechanism includes an upper arm and a lower arm; one end of the upper arm is hinged to one end of the lower arm, and the other end of the upper arm is hinged to the tail end of the fixed end of the front lifting and retracting actuator; the other end of the lower arm is hinged to one side of the shell of the front lifting buffer support.

4. The dual-mode take-off and landing UAV with multi-mission payload according to claim 2, characterized in that: The anti-torsion arm assembly comprises a mounting ring, an upper anti-torsion arm and a lower anti-torsion arm. The mounting ring is sleeved on the shell of the front buffer support and is coaxially rotatably connected thereto. The upper end of the lower anti-torsion arm is hinged to the outer side wall of the mounting ring, and the lower end of the lower anti-torsion arm is hinged to the upper end of the upper anti-torsion arm. The lower end of the upper anti-torsion arm is hinged to the front wheel. The rocker arm of the steering servo is hinged to the lower anti-torsion arm.

5. The dual-mode take-off and landing UAV with multi-mission payload according to claim 1, characterized in that: The main landing gear includes a main engine wheel, a brake device, an oblique support arm and a main landing gear shock absorber; the oblique support arm serves as the main support of the main landing gear, and its upper end is detachably connected to the second structural frame in the fuselage, and its lower end is equipped with a main engine wheel; the brake device is installed on the inner side of the main engine wheel and is used for braking the main engine wheel; the main landing gear shock absorber is an oil-gas shock absorber, and its shell end is detachably connected to the second structural frame, and its telescopic end is detachably connected to the oblique support arm, and the main landing gear shock absorber is used for shock absorption and buffering of the main landing gear.

6. The dual-mode take-off and landing UAV with multi-mission payload according to claim 1, characterized in that: The nose fairing includes two structures, one is a taxiing takeoff and landing mode fairing, which is used in the taxiing takeoff and landing mode; the other is a zero-length takeoff and landing mode fairing, which is used in the zero-length takeoff and landing mode; the two nose fairings have the same connection structure with the fuselage, and the difference between the two is that a switchable door is provided at the bottom of the taxiing takeoff and landing mode fairing, which is used to retract the front landing gear into the taxiing takeoff and landing mode fairing.

7. The dual-mode take-off and landing UAV with multi-mission payload according to claim 1, characterized in that: The skid buffer shock absorbing device includes a shock absorber, a skid support arm, a skid rod and a skid retracting and extending mechanism; the front end of the skid rod is hinged to the fuselage, the rear support end thereof is fixedly connected to the lower end of the skid support arm, and the upper end of the skid support arm is detachably hinged to the bottom of the fuselage; the shock absorber is an oil-gas type shock absorber, the shell end of which is hinged to the skid retracting and extending mechanism, and the telescopic end is hinged to the middle part of the skid support arm; the skid retracting and extending mechanism is installed in the fuselage, and is used to drive the skid support arm and the skid rod to flip and retract through the shock absorber.

8. The dual-mode take-off and landing UAV with multi-mission payload according to claim 7, characterized in that: The slide retracting and extending mechanism includes a slide retracting and extending actuator and a slide rail, the slide rail is arc-shaped, and a through slide groove is provided along the center of its profile, and the two slide rails are opposite to each other and symmetrically fixed to the third structural frame and the fourth structural frame in the fuselage; the fixed end of the slide retracting and extending actuator is fixed in the fuselage, and the telescopic end thereof is horizontally hinged with a sliding shaft, and the two ends of the sliding shaft are respectively slidably installed in the slide grooves of the two slide rails; the top end of the shock absorber shell is hinged with the sliding shaft; under the action of the slide retracting and extending actuator, when the sliding shaft is located at the bottom end of the slide rail, the slide buffer shock absorbing device is in a landing buffer state, and when the sliding shaft is located at the top end of the slide rail, the slide buffer shock absorbing device is in a retracted state.

9. The dual-mode take-off and landing UAV with multi-mission payload according to claim 8, characterized in that: The slide rail is an assembled structure, which is assembled by overlapping two sections of the slide rails and is used for removing the slide shaft when the slide skid is retracted and the actuator is disassembled.

10. The dual-mode take-off and landing UAV with multi-mission payload according to claim 1, characterized in that: The recovery parachute includes a parachute cabin, a parachute opening device and a main parachute. The parachute opening device and the main parachute are installed in the parachute cabin, and the parachute cabin is installed in the fuselage. The parachute opening device is used to drive the main parachute out of the cabin to open the parachute, and the main parachute is used to adjust the aerial recovery posture and aerodynamic deceleration of the drone.

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