Hollow ring structure multi-rotor UAV and control method thereof and storage, transportation and launching device thereof

Abstract

A multi-rotor UAV with a hollow ring structure, a control method thereof, and a storage, transportation and launch device thereof. The UAV includes a hollow ring, multiple power load components, a camera and edge computing module, a flight control and navigation module, and a satellite navigation antenna; the multiple power load components are evenly arranged on the hollow ring; the camera and edge computing module are symmetrically arranged on the hollow ring with the flight control and navigation module. The storage, transportation and launch device of the UAV includes an outer cylinder, an inner cylinder, a transmission bracket arranged at the center of the inner cylinder, and S groups of transmission components arranged on the transmission bracket; the transmission components can lift multiple UAVs in sequence. The present invention adopts a power load integrated design, which reduces replaceable parts and facilitates production, installation and maintenance; the hollow ring structure helps to realize the stacking of multiple UAVs and realize batch launch; the storage, transportation and launch device can realize the storage, transportation and launch of multiple UAVs; the present invention performs rotation control with the guidance camera as the center, which can realize rapid attitude adjustment.

Description

Technical Field

[0001] The present invention relates to a multi-rotor UAV and a control method thereof and a storage, transportation and launching device thereof, and in particular to a multi-rotor UAV with a hollow ring structure and a control method thereof and a storage, transportation and launching device thereof. Background Art

[0002] When a drone needs to carry a loaded ring to remotely drop and trap a target, the loaded rings carried by existing drones have technical problems such as lack of controllability after drop and low accuracy in trapping the target.

[0003] In addition, when the UAV acting as the mother aircraft drops a ring-shaped object with a payload, there are technical problems such as its large size, high cost, and the need for recovery and monitoring.

[0004] To this end, a drone is needed that can carry a payload ring, does not require recovery, does not require remote monitoring after delivery, has high delivery accuracy, and is easy to store, transport and launch. Summary of the invention

[0005] The purpose of the present invention is to provide a new hollow ring structure multi-rotor UAV, its control method and its storage, transportation and launch device, which solves the technical problems of existing UAVs such as large size, high cost and need for recovery and monitoring, and also solves the technical problem of low delivery accuracy of ring-shaped objects dropped by existing UAVs. At the same time, it also solves the technical problem of poor control and guidance capabilities of hollow ring structure multi-rotor UAVs.

[0006] The technical solution of the present invention is:

[0007] A multi-rotor UAV with a hollow ring structure is special in that it includes a hollow ring, multiple power load components, a camera and edge computing module, a flight control and navigation module, and a satellite navigation antenna; the multiple power load components are evenly arranged on the hollow ring; the camera and edge computing module are symmetrically arranged on the hollow ring and are respectively located between two power load components on the hollow ring; and the satellite navigation antenna is arranged on the hollow ring.

[0008] The above-mentioned power load assembly specifically includes a motor mounting seat, a flight motor arranged above the motor mounting seat, a rotor arranged above the flight motor, a load arranged below the motor mounting seat, and a battery arranged in the motor mounting seat; the inner side surface of the motor mounting seat is connected to the hollow ring.

[0009] The above-mentioned camera and edge computing module includes an AI computer, a gimbal and a guide camera; the AI ​​computer is connected to the hollow ring, the gimbal is arranged below the AI ​​computer, and the guide camera is arranged below the gimbal.

[0010] A lateral inclination angle α of a pulling force vector is set between the axis of the flight motor and the vertical normal of the power load component; the value range of α is 2-10°.

[0011] The value range of the above α is preferably 3-5°.

[0012] A load folding structure is arranged between the motor mounting seat and the load; the load folding structure is used for switching the spatial state of the load relative to the motor; the hollow ring is a hollow tube structure; the satellite navigation antenna is a GNSS antenna, two in number and symmetrically distributed on the hollow ring; the rotor is a straight-line rotor; the number of the power load assemblies is four, and the axes of the four power load assemblies are inclined inward and converge below the hollow ring with the center normal of the hollow ring.

[0013] The control method of the hollow ring structure multi-rotor drone comprises the following steps:

[0014] 1) The ground station injects the target location data and uses the satellite navigation system, flight control and navigation modules to guide the hollow ring structure multi-rotor drone to the vicinity of the target area;

[0015] 2) Automatically identify the target;

[0016] 3) Based on visual guidance technology and visual servo control technology, the hollow ring structure multi-rotor drone is guided to the top of the target;

[0017] 4) Perform rotation control with the position of the guidance camera as the center to achieve attitude adjustment, so that the hollow ring structure multi-rotor drone hovers above the target object and is finally placed on the target object.

[0018] The above rotation control with the position of the guidance camera as the center is specifically controlled according to the control distribution relationship between the three-axis torque and the pulling force to the throttle:

[0019]

[0020] Where: t1 ,δ t2 ,δ t3 ,δ t4 The throttle command for each flight motor;

[0021] L, M, N, and T are the triaxial moments and tensions;

[0022] is the throttle pull coefficient and torque coefficient;

[0023] r is the radius of the ring structure;

[0024] G is gravity.

[0025] The storage, transportation and launching device of the above-mentioned hollow ring structure multi-rotor UAV is special in that it includes a storage and transportation device and a launching device; the storage and transportation device includes a covered outer cylinder and an uncovered inner cylinder; the inner cylinder is axially provided with S upper-open conveyor belt grooves; the S≥3; the launching device includes a conveying bracket arranged at the center of the inner cylinder, and S groups of circumferentially evenly distributed conveying components arranged on the conveying bracket; the conveying component includes a conveying motor with an outer rotor structure arranged above the conveying bracket, a pulley arranged below the conveying bracket, and a conveyor belt wound between the conveying motor and the pulley and located in the conveyor belt groove; a plurality of support plates perpendicular to the conveyor belt are arranged on the outer side of the conveying belt; the S support plates located at the same height jointly support a hollow ring of a hollow ring structure multi-rotor UAV.

[0026] The above S=4; the outer tube is provided with an inflation interface and an exhaust interface.

[0027] The present invention has the following beneficial effects:

[0028] 1. The hollow ring structure multi-rotor UAV of the present invention adopts a modular integrated design of the power system and the payload, which reduces the replaceable parts and facilitates the early production installation and later use and maintenance. The entire system consists only of a hollow ring structure (with built-in cables), a power payload assembly, a flight control navigation assembly, and a guide assembly. The power system and payload weight account for more than 70%. Through the integrated design of the power payload, the power payload assembly directly bears its own gravity and rotor pull, which greatly reduces the strength requirements of the hollow ring structure.

[0029] 2. The hollow ring structure of the multi-rotor drone of the present invention can house cables to protect the cables from environmental influences.

[0030] 3. The hollow ring structure of the multi-rotor UAV of the present invention does not have any components inside, which helps to be put on the inner cylinder of the storage, transportation and launch device to achieve stacking of multiple UAVs, reduce storage space, and realize batch launch.

[0031] 4. All components of the hollow ring structure multi-rotor drone of the present invention are arranged on the hollow ring structure, which can ensure structural balance and facilitate control.

[0032] 5. When designing the power load assembly of the hollow ring structure multi-rotor UAV of the present invention, there is a small lateral installation angle between the tension vector and the vertical normal of the power assembly, thereby forming a lateral force acting on the hollow ring structure. The four rotors are differentially driven in pairs to provide enhanced yaw control, solving the problems of slow yaw control speed and insufficient heading control capability caused by the large moment of inertia.

[0033] 6. The general control method of multi-rotor drones is a rotation control method around the center of gravity. When the posture changes, the spatial position of the camera will change greatly, which is very unfavorable for terminal guidance. The hollow ring structure multi-rotor drone of the present invention needs to adjust its posture. Since the guidance camera is installed on the hollow ring structure, the new control distribution matrix of the present invention can make the drone rotate around the position of the camera as the center when adjusting its posture, thereby solving the special rotation and translation coupling problems caused by the hollow ring structure during the terminal guidance process.

[0034] 7. The hollow ring structure multi-rotor UAV storage, transportation and launching device of the present invention has an outer cylinder that can seal and store UAVs, and an inner cylinder that can fix multiple UAVs. It can also ensure the stability of the UAVs when they are transmitted and launched in sequence, thereby realizing an integrated design of storage, transportation and launching of multiple UAVs.

[0035] 8. The hollow ring structure multi-rotor UAV of the present invention uses terminal guidance to trap the target object faster and more accurately.

[0036] 9. The hollow ring structure multi-rotor UAV of the present invention does not need to be recovered after launch, has its own control, navigation, guidance, and target recognition functions, and can complete tasks autonomously.

[0037] 10. The payload of the hollow ring structure multi-rotor UAV of the present invention adopts a folding structure, which can realize stacking of multiple racks on the inner tube, thereby reducing storage and transportation space.

[0038] 11. The present invention adopts a straight-line rotor, which is convenient for saving storage space and can be sleeved on the inner cylinder.

[0039] 12. The dynamic load assembly of the present invention can be deployed to serve as a landing gear.

[0040] 13. The hollow ring structure multi-rotor UAV of the present invention has higher working efficiency and lower overall cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the three-dimensional structure of the hollow ring structure multi-rotor UAV of the present invention;

[0042] Figure 2 1. It is a top view of the hollow ring structure multi-rotor UAV of the present invention;

[0043] Figure 3 It is a side view of the hollow ring structure multi-rotor UAV of the present invention;

[0044] Figure 4 It is a structural schematic diagram of a power load assembly in a hollow ring structure multi-rotor UAV of the present invention;

[0045] Figure 5It is a schematic diagram of the centripetal folding of the power load assembly in the hollow ring structure multi-rotor UAV of the present invention;

[0046] Figure 6 It is a schematic diagram of the lateral folding of the power load assembly in the hollow ring structure multi-rotor UAV of the present invention;

[0047] Figure 7 Schematic diagram of the motor installation inclination angle of the hollow ring structure multi-rotor UAV of the present invention;

[0048] Figure 8 It is a structural schematic diagram of the storage, transportation and launching device of the present invention;

[0049] Fig. 9 It is a structural schematic diagram of the storage and transportation device in the storage and transportation launching device of the present invention;

[0050] Fig.10 It is a structural schematic diagram of the launching device in the storage and transportation launching device of the present invention;.

[0051] Fig.11 It is a schematic diagram of multiple drones placed in a launch device;

[0052] Fig.12 It is a top view of multiple drones placed in the launcher;

[0053] Fig.13 Schematic diagram of the control distribution matrix of the hollow ring structure multi-rotor UAV of the present invention;

[0054] Fig.14 This is a control principle diagram of a multi-rotor UAV with a hollow ring structure according to the present invention.

[0055] Reference numerals:

[0056] 1-first power load component, 2-second power load component, 3-third power load component, 4-fourth power load component; 11-outer cylinder; 12-inner cylinder; 13-conveyor belt groove; 14-conveyor belt; 15-conveyor motor; 16-conveyor bracket; 17-pallet; 18-pulley; 19-gimbal; 21-rotor; 22-AI computer; 23-guidance camera; 24-payload; 25-battery; 26-hollow ring; 27-satellite navigation antenna; 28-motor mounting seat; 29-flight control and navigation module; 20-flight motor. DETAILED DESCRIPTION

[0057] like Figures 1 to 3As shown, the hollow ring structure multi-rotor UAV of the present invention includes a hollow ring 26, four power load components, a camera and edge computing module, a flight control and navigation module 29, and two satellite navigation antennas 27; the four power load components are evenly arranged on the hollow ring 26; the camera and edge computing module and the flight control and navigation module 29 are symmetrically arranged on the hollow ring 26 and are respectively located between the two power load components; the camera and edge computing module, the flight control and navigation module 29 and the two satellite navigation antennas 27 are respectively arranged between two adjacent power load components, and the two satellite navigation antennas are symmetrically arranged, which can realize dual-antenna directional positioning. The satellite navigation antenna can adopt a GNSS antenna. The four power load components are respectively a first power load component 1, a second power load component 2, a third power load component 3 and a fourth power load component 4.

[0058] like Figures 3 to 7 As shown, the power load assembly adopts an integrated design, including a motor mount 28, a flight motor 20 arranged above the motor mount 28, a rotor 21 arranged above the flight motor 20, a load 24 arranged below the motor mount 28, a battery 25 and an electric regulator arranged in the motor mount 28; the inner side of the motor mount 28 is connected to the hollow ring 26. The power load assembly can be deployed to serve as a landing gear. The axes of the four power load assemblies are inclined inward and converge with the center normal of the hollow ring below the hollow ring.

[0059] The camera and edge computing module includes an AI computer 22, a pan-tilt 19, and a guidance camera 23; the AI ​​computer 22 is connected to a hollow ring 26, the pan-tilt 19 is arranged below the AI ​​computer 22, and the guidance camera 23 is arranged below the pan-tilt 19. The AI ​​computer, the camera, and the pan-tilt complete the target recognition and terminal guidance functions.

[0060] The flight control and navigation module 29 supports Beidou positioning, and can also use visual odometer technology for visual positioning during the guidance phase.

[0061] A lateral inclination angle α of the pulling force vector is set between the axis of the flight motor 20 and the vertical normal of the power load component; the value range of α is preferably 3-5°.

[0062] In order to reduce the space occupied by the hollow ring structure rotor UAV, a load folding structure is provided between the motor mounting seat 28 and the power load assembly; the load folding structure is used to switch the spatial state of the load relative to the motor; the four loads can be folded, and the minimum height after folding is 150mm. The folding method is centripetal folding or lateral folding; the lateral folding method is adopted, which occupies the lateral space that is difficult to use, so that the middle is completely empty after folding. The central axis (tension vector) of the flight motor 20 is laterally inclined and tangent to the cylindrical surface of the annular structure and has an angle of 3° to 5° with the normal line of the plane of the annular mechanism. The central axes of the four groups of power load assemblies are inclined inward and converge at one point with the central normal line of the hollow ring 26.

[0063] The hollow ring 26 is a hollow tube structure for placing cables. The rotor is a straight-line rotor, which can save space.

[0064] like Figures 8 to 12 As shown, the integrated storage, transportation and launching device of the present invention includes a control device, a storage and transportation device and a launching device; the storage and transportation device includes a covered outer cylinder 11 and an uncovered inner cylinder 12; the inner cylinder 12 is axially provided with four upper open conveyor belt grooves 13. The launching device includes a conveyor bracket 16 arranged at the center of the inner cylinder, and four groups of circumferentially evenly distributed conveyor components arranged on the conveyor bracket 16; the conveyor component includes a conveyor motor 15 with an outer rotor structure arranged above the conveyor bracket 16, a pulley 18 arranged below the conveyor bracket 16, and a conveyor belt 14 wound between the conveyor motor 15 and the pulley 18 and located in the conveyor belt groove 13; a plurality of support plates 17 perpendicular to the conveyor belt 14 are arranged on the outer surface of the conveyor belt 14; four support plates 17 at the same height jointly support a hollow ring 26 of a multi-rotor drone with a hollow ring structure. Considering long-term storage, an inflation interface and an exhaust interface can be provided on the outer cylinder for nitrogen filling. The conveyor motor drives the conveyor belt to rotate, and the conveyor belt drives the support plate to move upward, thereby lifting the drone to the take-off position, and the drone automatically takes off. The conveyor motor and rollers can also be interchanged.

[0065] The hollow ring structure rotor drone can be mounted on the wall of the inner cylinder 12. It is best to fold multiple drones and then stack them on the inner cylinder wall. The control device is installed in the inner space of the inner cylinder. The hollow ring structure multi-rotor drone adopts cluster working mode and also supports single-machine working mode. No human intervention is required in the cluster working mode.

[0066] The control method of the hollow ring structure multi-rotor drone of the present invention comprises the following steps:

[0067] 1) The ground station injects the target location data and uses the satellite navigation system to guide the hollow ring structure multi-rotor drone to the vicinity of the target area;

[0068] 2) Automatically identify targets based on deep learning target recognition technology;

[0069] 3) Based on visual guidance technology and visual servo control technology, the hollow ring structure multi-rotor drone is guided to the top of the target;

[0070] 4) Rotation control is performed with the position of the guidance camera 23 as the center to achieve rapid attitude adjustment, and based on the robust adaptive anti-interference control technology, the hollow ring structure multi-rotor drone is hovered above the target object in a wind interference environment.

[0071] The basic principle of rotation control with the position of the guiding camera 23 as the center is shown in Fig.13 :

[0072] The control distribution matrix is ​​designed with the position of the guidance camera 23 as the center. As shown in the following formula, the throttle of each motor and the resulting force and torque have the following relationship:

[0073]

[0074] where δ t1 ,δ t2 ,δ t3 ,δ t4 is the throttle command, L, M, N, T are the three-axis torque and tension, is the throttle force coefficient and torque coefficient, r is the radius of the ring structure, and G is the gravity. By inverting the matrix, we can get the control distribution relationship between the three-axis torque and force to the throttle:

[0075]

[0076] Compared with ordinary multi-rotor drones, the control principle of the hollow ring structure multi-rotor drone of the present invention can be found in Fig.14 :

[0077] 1) Hollow ring structure The mass of the multi-rotor drone is distributed on the hollow ring 26, and the z-axis moment of inertia is large. If only relying on the axial torque of the rotor itself, the yaw control speed will be slow and the yaw control ability will be insufficient.

[0078] When designing the power load component of the UAV of the present invention, a small lateral installation angle exists between the tension vector and the vertical normal of the power load component, thereby forming a lateral force acting on the hollow ring structure. The four rotors are differentially driven in pairs to provide enhanced yaw control, thereby solving the problem of insufficient heading control capability caused by the large moment of inertia.

[0079] Fig.14 In the equation, T is the pulling force vector, T v ,T h are the vertical and horizontal components of the pull vector, and α is the lateral inclination angle of the pull vector. When there is no tilt, the yaw moment generated is:

[0080]

[0081] The yaw moment after tilting consists of two parts. The propeller torque is:

[0082]

[0083] Due to the large radius r, the yaw moment is significantly increased through the lateral tilting of the pull vector.

[0084] 2) When adjusting the position, the multi-rotor UAV needs to adjust the attitude. Since the guidance camera 23 is installed on the hollow ring 26, according to the general multi-rotor UAV control method (rotation around the center of gravity), when the attitude changes, it will cause a large change in the spatial position of the guidance camera 23, which is very unfavorable for terminal guidance. Therefore, the control allocation matrix of the hollow ring structure multi-rotor UAV is redesigned so that when adjusting the attitude, the guidance camera 23 is located as the center for rotation control, thereby solving the special rotation and translation coupling problem caused by the hollow ring structure during the terminal guidance process.

Claims

1. A multi-rotor drone with a hollow ring structure, Features: It includes a hollow ring (26), a plurality of power load components, a camera and edge computing module, a flight control and navigation module (29), and a satellite navigation antenna (27); The plurality of dynamic load components are evenly arranged on the hollow ring (26); Each of the power load components comprises a motor mounting seat (28), a flight motor (20) arranged above the motor mounting seat (28), a rotor (21) arranged above the flight motor (20), a load (24) arranged below the motor mounting seat (28), and a battery (25) arranged in the motor mounting seat (28); the motor mounting seat (28) is connected to the hollow ring (26); The camera and edge computing module are symmetrically arranged on the hollow ring (26) with the flight control and navigation module (29) and are respectively located between the two power load components; The satellite navigation antenna (27) is arranged on the hollow ring (26).

2. According to claim 1, the hollow ring structure multi-rotor drone, Features: The camera and edge computing module includes an AI computer (22), a pan / tilt (19) and a guidance camera (23); The AI ​​computer (22) is connected to the hollow ring (26), the pan-tilt platform (19) is arranged below the AI ​​computer (22), and the guiding camera (23) is arranged below the pan-tilt platform (19).

3. The hollow ring structure multi-rotor drone according to claim 1 or 2, Features: A lateral inclination angle α of a pulling force vector is provided between the axis of the flight motor (20) and the vertical normal of the power load component; the value range of α is 2-10°.

4. According to claim 3, the hollow ring structure multi-rotor drone, Features: The value range of α is 3-5°.

5. According to claim 3, the hollow ring structure multi-rotor drone, Features: A load folding structure is provided between the motor mounting seat (28) and the load (24); the load folding structure is used for switching the spatial state of the load relative to the motor; The hollow ring (26) is a hollow tube structure; The satellite navigation antenna (27) is a GNSS antenna, two in number and symmetrically distributed on the hollow ring (26); The rotor (21) is a straight-line rotor; The number of the dynamic load components is four, and the lower ends of the axes of the four dynamic load components are inclined inwards and converge with the center normal of the hollow ring (26) below the hollow ring (26).

6. A control method for a hollow ring structure multi-rotor drone according to any one of claims 1 to 5, It is characterized in that The following steps are involved: 1) The ground station injects the target location data and uses the satellite navigation system and the flight control and navigation module (29) to guide the hollow ring structure multi-rotor UAV to the vicinity of the target area; 2) Automatically identify the target; 3) Based on visual guidance technology and visual servo control technology, the hollow ring structure multi-rotor drone is guided to the top of the target; 4) Rotation control is performed with the position of the guidance camera (23) as the center to achieve attitude adjustment, so that the hollow ring structure multi-rotor drone hovers above the target object, and finally the hollow ring (26) is set on the target object.

7. The control method according to claim 6, It is characterized in that In step 4), the rotation control with the position of the guidance camera (23) as the center is specifically controlled according to the control distribution relationship between the three-axis torque and the pulling force to the throttle: Where: t1 ,δ t2 ,δ t3 ,δ t4 The throttle command for each flight motor; L, M, and N are the three-axis moments; T is the tension; is the throttle pull coefficient and torque coefficient; r is the radius of the ring structure; G is gravity.

8. A storage, transportation and delivery device for a hollow ring structure multi-rotor UAV according to any one of claims 1 to 5, Features: It includes storage and transportation devices and launching devices; The storage and transportation device comprises an outer cylinder (11) with a cover and an inner cylinder (12) without a cover; the inner cylinder (12) is axially provided with S conveyor belt grooves (13) with upper openings; S is ≥ 3; The launching device comprises a conveying support (16) arranged at the center of the inner cylinder (12), S groups of circumferentially evenly distributed conveying components arranged on the conveying support (16); the conveying component comprises a conveying motor (15) with an outer rotor structure arranged above the conveying support (16), a pulley (18) arranged below the conveying support (16), and a conveying belt (14) wound between the conveying motor (15) and the pulley (18) and located in a conveying belt groove (13); a plurality of support plates (17) perpendicular to the conveying belt (14) are arranged on the outer side of the conveying belt (14); S supporting plates (17) located at the same height jointly support a hollow ring (26) of a multi-rotor drone with a hollow ring structure.

9. The storage, transportation and delivery device according to claim 8, Features: Said S=4; The outer cylinder (11) is provided with an air charging interface and an air discharging interface.

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