A two-axis gimbal of an unmanned aerial vehicle and a control method thereof

Abstract

The invention discloses a two-axis gimbal of an unmanned aerial vehicle and a control method thereof, which relates to the technical field of unmanned aerial vehicles, and includes a bracket, a camera, an upper driving structure, a lower driving structure and a conductive slip ring, wherein the camera is arranged on the bracket, the camera is rotatably connected to the bracket, the upper driving structure drives the camera to rotate around a first axis, the wires of the camera and the wires of the upper driving structure are both connected to the conductive slip ring, the rotating end of the conductive slip ring is connected to the lower driving structure and the bracket, the lower driving structure drives the camera to rotate around a second axis, the upper driving structure and the lower driving structure are both horizontally arranged, and the first axis is perpendicular to the second axis. The invention avoids the layout mode of the traditional gimbal that requires two motors to be arranged vertically, and greatly reduces the volume of the gimbal; the circuit connection mode of the invention can enable the camera to achieve 360-degree rotation without dead angles, and can rotate infinitely and continuously around the axis of the conductive slip ring without limit.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and in particular to a two-axis gimbal of an unmanned aerial vehicle and a control method thereof. Background Art

[0002] As a new shooting method, drone aerial photography is widely used in the film and television industry and daily entertainment. With the widespread application of small drone products, people's requirements for airborne aerial photography equipment are getting higher and higher. Traditional fixed cameras can no longer meet people's needs. Users are eager to be able to freely adjust the camera to control the shooting angle.

[0003] In the prior art, a Chinese patent with publication number CN207664746U discloses a driving device for a two-axis gimbal, which includes a roll axis motor, a pitch axis motor and a camera support seat. By configuring two DC brushless motors installed perpendicularly to each other, the stability of the two-degree-of-freedom (i.e., two-axis) gimbal can be achieved; in addition, a Chinese patent with publication number CN204124373U discloses a dual-axis video gimbal structure for a drone, including a fixed chassis, a turntable, a camera bracket, a first driving mechanism and a second driving mechanism. The first driving mechanism and the second driving mechanism are used to respectively control the swing of the turntable and the connecting bracket to realize the rotational movement of the camera in the directions of two perpendicular axes.

[0004] On the one hand, in order to achieve rotation in two directions, the existing gimbal structure often adopts a combination of two mutually perpendicular brushless motors or servo steering gears, which requires a larger space in the structure and therefore cannot be miniaturized; on the other hand, the first rotating mechanism directly connected to the camera is often driven by the second rotating mechanism, so the connecting line of the first transmission mechanism motor needs to rotate with the camera, and continuous rotation cannot be achieved. Summary of the invention

[0005] The purpose of the present invention is to provide a two-axis gimbal for an unmanned aerial vehicle and a control method thereof, so as to solve the problems existing in the above-mentioned prior art, effectively reduce the volume of the traditional gimbal, and improve the flexibility of gimbal control.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a two-axis gimbal of an unmanned aerial vehicle, comprising a bracket, a camera, an upper driving structure, a lower driving structure and a conductive slip ring, wherein the camera is arranged on the bracket, the camera is rotatably connected to the bracket, the upper driving structure drives the camera to rotate around a first axis, the wires of the camera and the wires of the upper driving structure are both connected to the conductive slip ring, the rotating end of the conductive slip ring is connected to the lower driving structure and the bracket, the lower driving structure drives the camera to rotate around a second axis, the upper driving structure and the lower driving structure are both horizontally arranged, and the first axis is perpendicular to the second axis.

[0008] Preferably, it also includes a camera cover, an output gear and an upper gear, the upper driving structure is arranged on the camera cover, the camera is connected to the camera cover, the upper gear is connected to the bracket, the output gear is arranged on the output shaft of the upper driving structure, the output gear is meshed with the upper gear, and the upper driving structure drives the output gear to rotate, thereby driving the camera and the camera cover to rotate around the first axis.

[0009] Preferably, a first through hole is provided on the camera cover, the body of the upper driving structure is connected to the camera cover, and the output shaft of the upper driving structure passes through the first through hole; second through holes are respectively provided on both sides of the camera cover, connecting holes corresponding to the second through holes are respectively provided on both sides of the camera, and mounting holes corresponding to the second through holes are provided on the bracket, and a first bearing is provided in each of the mounting holes, and a screw passes through the first bearing, the upper gear, the second through hole and the connecting hole in sequence, and the camera cover and the camera are rotatably connected to the bracket through the first bearing.

[0010] Preferably, it also includes a turntable and a chassis, the turntable is arranged above the chassis, and the turntable is rotatably connected to the chassis, the bracket is arranged on the turntable, the fixed ends of the lower driving structure and the conductive slip ring are both arranged on the chassis, the rotating end of the conductive slip ring is connected to the turntable, and the turntable is provided with wire holes for the wires of the camera and the wires of the upper driving structure to pass through.

[0011] Preferably, it also includes a worm, a lower gear and a driving gear, the worm is arranged on the output shaft of the lower driving structure, the lower gear is arranged on the chassis, the driving gear is sleeved on the rotating end of the conductive slip ring, the worm is meshed with the lower gear, the lower gear is meshed with the driving gear, and the lower driving structure drives the worm to rotate, thereby driving the lower gear, the driving gear, the conductive slip ring and the camera to rotate around the second axis.

[0012] Preferably, a fixing hole is provided at the bottom of the chassis, and the fixed end of the conductive slip ring is arranged in the fixing hole; a through hole for an image transmission antenna is opened on the side wall of the chassis for the image transmission antenna to pass through; the lower driving structure is arranged on the base on the chassis, and the lower gear is rotatably connected to the mounting base on the chassis.

[0013] Preferably, the upper driving structure and the lower driving structure are both reduction stepping motors.

[0014] Preferably, it also includes a lower circuit board, which includes a signal conversion module and an image transmission module. The signal conversion module is provided with a pwm1 input terminal, a pwm2 input terminal, a V input terminal, a G input terminal, an A+ output terminal, an A- output terminal, a B+ output terminal, a B- output terminal, a C+ output terminal, a C- output terminal, a D+ output terminal and a D- output terminal. The image transmission module is provided with a V output terminal, a G output terminal and an S output terminal. The V output terminal, the G output terminal and the S output terminal of the image transmission module are connected to the camera through the conductive slip ring, the A+ output terminal, the A- output terminal, the B+ output terminal and the B- output terminal of the signal conversion module are connected to the upper drive structure through the conductive slip ring, and the C+ output terminal, the C- output terminal, the D+ output terminal and the D- output terminal of the signal conversion module are connected to the lower drive structure.

[0015] Preferably, the signal conversion module includes a main control chip and two driver chips. The main control chip receives pwm1 and pwm2 signals respectively through two IO ports. After the pwm1 and pwm2 signals pass through the signal conversion program, they drive the upper driving structure and the lower driving structure respectively through one of the driver chips.

[0016] The present invention also provides a method for controlling the two-axis gimbal of the unmanned aerial vehicle, comprising the following steps:

[0017] The pwm1 signal output by the receiver is connected to the IO1 port of the main control chip as an input signal;

[0018] Determine the sign of pwm1-1500. If it is positive, configure the IO2 port dir1 of the main control chip to 1. Otherwise, output dir1 to 0.

[0019] Select the proportional coefficient k1 and configure the IO3 port of the main control chip to output the square wave signal step1, whose frequency is determined by k1|pwm1-1500|;

[0020] Connect the IO2 port and the IO3 port to the dir1 port and step1 port of a driver chip respectively;

[0021] A driver chip converts the input dir1 and step1 signals into A+, A-, B+, B-, and connects them to the lower drive structure through a conductive slip ring;

[0022] At the same time, the pwm2 signal output by the receiver is connected to the IO4 port of the main control chip as an input signal;

[0023] Determine the sign of pwm2-1500. If it is positive, configure the IO5 port of the main control chip to dir2=1. Otherwise, output dir2=0.

[0024] Select the proportional coefficient k2 and configure the IO6 port of the main control chip to output the square wave signal step2, whose frequency is determined by k2|pwm2-1500|;

[0025] Connect the IO5 port and IO6 port to the dir2 and step2 ports of another driver chip respectively;

[0026] Another driver chip converts the input dir2 and step2 signals into C+, C-, D+, and D-, and connects them to the lower-level driver structure.

[0027] Compared with the prior art, the present invention has achieved the following technical effects:

[0028] The present invention avoids the traditional pan-tilt structure that requires two motors to be arranged vertically, thereby greatly reducing the size of the pan-tilt structure. By adopting the circuit connection method of the present invention, the camera can achieve 360-degree rotation without dead angles, and can rotate infinitely and continuously around the axis of the conductive slip ring without any limit. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 This is a schematic diagram of a two-axis gimbal of a UAV of the present invention;

[0031] Figure 2 This is a schematic diagram of the two-axis gimbal of the drone of the present invention (without the chassis);

[0032] Figure 3 The upper structure of the turntable of the present invention is schematically shown in FIG. Figure 1 ;

[0033] Figure 4 The upper structure of the turntable of the present invention is schematically shown in FIG. Figure 2 ;

[0034] Figure 5 for Figure 4 Exploded diagram of

[0035] Figure 6 The upper drive structure, camera cover and camera explosion diagram of the present invention;

[0036] Figure 7 It is a schematic diagram of the structure of the turntable, conductive slip ring and driving gear of the present invention;

[0037] Figure 8 It is a schematic diagram of various structures inside the chassis of the present invention;

[0038] Fig. 9 It is a schematic diagram of the lower layer driving structure, conductive slip ring, lower layer gear and driving gear structure of the present invention;

[0039] Fig.10 It is a schematic diagram of the control relationship among the image transmission module, the signal conversion module, the conductive slip ring, the camera, the upper driving structure and the lower driving structure of the present invention;

[0040] Among them: 100-UAV two-axis gimbal; 1-camera, 101-connection hole; 2-camera cover, 201-second through hole, 202-first through hole; 3-bracket; 4-first bearing; 5-screw; 6-upper gear; 7-turntable, 701-wire hole; 8-upper drive structure; 9-conductive slip ring; 10-drive gear; 11-lower gear; 12-second bearing; 13-lower drive structure; 14-chassis, 1401-mounting seat, 1402-card holder, 1403-fixing hole, 1404-image transmission antenna through hole. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The purpose of the present invention is to provide a two-axis gimbal for an unmanned aerial vehicle and a control method thereof, so as to solve the problems existing in the above-mentioned prior art, effectively reduce the volume of the traditional gimbal, and improve the flexibility of gimbal control.

[0043] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0044] Embodiment 1

[0045] like Figure 1-Figure 10 As shown: This embodiment provides a two-axis gimbal 100 for an unmanned aerial vehicle, including a bracket 3, a camera 1, an upper driving structure 8, a lower driving structure 13 and a conductive slip ring 9. The camera 1 is preferably an FPV camera, which is arranged on the bracket 3. The camera 1 is rotatably connected to the bracket 3. The upper driving structure 8 drives the camera 1 to rotate around a first axis. The wires of the camera 1 and the wires of the upper driving structure 8 are both connected to the conductive slip ring 9. The rotating end of the conductive slip ring 9 is connected to the lower driving structure 13 and the bracket 3. The lower driving structure 13 drives the camera 1 to rotate around a second axis. The upper driving structure 8 and the lower driving structure 13 are both horizontally arranged, and the first axis is perpendicular to the second axis.

[0046] Specifically, in this embodiment, it also includes a camera cover 2, an output gear and an upper gear 6. The upper driving structure 8 is arranged on the camera cover 2, the camera 1 is connected to the camera cover 2, the upper gear 6 is connected to the bracket 3, and the output gear sleeve is arranged at the end of the output shaft of the upper driving structure 8 away from the body of the upper driving structure 8. The output gear is meshed with the upper gear 6, and the upper driving structure 8 drives the output gear to rotate, thereby driving the camera 1 and the camera cover 2 to rotate around the first axis.

[0047] In this embodiment, a first through hole 202 is provided on the camera cover 2, the body of the upper driving structure 8 is connected to the camera cover 2, the output shaft of the upper driving structure 8 passes through the first through hole 202 and the output shaft of the upper driving structure 8 is rotatably connected to the camera cover 2; second through holes 201 are respectively provided on both sides of the camera cover 2, and connecting holes 101 corresponding to the second through holes 201 are respectively provided on both sides of the camera 1, and mounting holes corresponding to the second through holes 201 are provided on the bracket 3, and a first bearing 4 is provided in each mounting hole, and the first bearing 4, the upper gear 6, the second through hole 201 and the connecting hole 101 are coaxially arranged, and the screw 5 passes through the first bearing 4, the upper gear 6, the second through hole 201 and the connecting hole 101 in sequence, and the screw 5 is threadedly connected to the connecting hole 101, and the camera cover 2 and the camera 1 are both rotatably connected to the bracket 3 through the first bearing 4.

[0048] In this embodiment, a turntable 7 and a chassis 14 are also included. The turntable 7 is arranged above the chassis 14, and the turntable 7 is rotatably connected to the chassis 14. The lower end of the bracket 3 is arranged on the turntable 7. The lower driving structure 13 is arranged on the base 1402 on the chassis 14 and is fixedly connected to the base 1402. A fixing hole 1403 is arranged at the bottom of the chassis 14. The fixed end of the conductive slip ring 9 is arranged in the fixing hole 1403 and is coaxially tightly connected to the fixing hole 1403. The rotating end of the conductive slip ring 9 is coaxially tightly connected to the sleeve on the lower surface of the turntable 7. A wire hole 701 is provided on the turntable 7 for three wires of the camera 1 and four wires of the upper driving structure 8 to pass through. The side wall of the chassis 14 is provided with an image transmission antenna through hole 1404 for the image transmission antenna to pass through.

[0049] In this embodiment, it also includes a worm, a lower gear 11 and a driving gear 10. The worm is arranged on the output shaft of the lower driving structure 13, the lower gear 11 is arranged on the chassis 14, and the lower gear 11 is rotatably connected to the mounting seat 1401 on the chassis 14 through the second bearing 12. The driving gear 10 is sleeved on the rotating end of the conductive slip ring 9 and is coaxially tightly connected with the rotating end of the conductive slip ring 9. The worm is meshed with the lower gear 11, and the lower gear 11 is meshed with the driving gear 10. The lower driving structure 13 drives the worm to rotate, thereby driving the lower gear 11, the driving gear 10, the conductive slip ring 9 and the camera 1 to rotate around the second axis.

[0050] In this embodiment, both the upper driving structure 8 and the lower driving structure 13 are reduction stepping motors.

[0051] In this embodiment, a lower circuit board is also included, and the lower circuit board includes a signal conversion module and an image transmission module. The signal conversion module is provided with a pwm1 input terminal, a pwm2 input terminal, a V input terminal, a G input terminal, an A+ output terminal, an A- output terminal, a B+ output terminal, a B- output terminal, a C+ output terminal, a C- output terminal, a D+ output terminal and a D- output terminal. The image transmission module is provided with a V output terminal, a G output terminal and an S output terminal. The V output terminal, the G output terminal and the S output terminal of the image transmission module are connected to the camera 1 through a conductive slip ring 9, the A+ output terminal, the A- output terminal, the B+ output terminal and the B- output terminal of the signal conversion module are connected to the upper drive structure 8 through a conductive slip ring 9, and the C+ output terminal, the C- output terminal, the D+ output terminal and the D- output terminal of the signal conversion module are connected to the lower drive structure 13.

[0052] In this embodiment, the signal conversion module includes a main control chip and two driver chips. The main control chip is preferably an STM32 main control chip, and the driver chip is preferably a TMC2209 driver chip. The STM32 main control chip receives pwm1 and pwm2 signals respectively through two IO ports. After the pwm1 and pwm2 signals pass through the signal conversion program, they are respectively driven by a TMC2209 driver chip to drive the upper driver structure 8 and the lower driver structure 13.

[0053] When working, the receiver outputs the pwm1 signal through the signal conversion module to obtain four signals of A+, A-, B+, and B-, which are connected to the upper drive structure 8 through the conductive slip ring 9 to drive the upper drive structure 8 to rotate. The rotation direction is determined by the sign of pwm1-1500, and the rotation speed is determined by k1|pwm1-1500|. The output gear of the upper drive structure 8 drives the camera 1 to rotate around the axis (first axis) of the upper gear 6 through the upper gear 6.

[0054] The receiver outputs the pwm2 signal, which is converted into four signals, C+, C-, D+, and D-, and connected to the lower drive structure 13 to drive the lower drive structure 13 to rotate. The rotation direction is determined by the sign of pwm2-1500, and the rotation speed is determined by k2|pwm2-1500|. The worm of the lower drive structure 13 drives the lower gear 11 to rotate, and the lower gear 11 drives the drive gear 10 to rotate. The drive gear 10 drives the conductive slip ring 9 to rotate, and the conductive slip ring 9 drives the turntable 7 to rotate. The turntable 7 drives the camera 1 to rotate around the axis (second axis) of the conductive slip ring 9 through the bracket 3.

[0055] The volume of the two-axis gimbal 100 of the drone of this embodiment is less than 38mm*38mm*38mm, and the weight is less than 15g, which is suitable for 14mm / 19mm FPV cameras; this embodiment avoids the layout of the traditional gimbal that requires two motors to be arranged vertically, and greatly reduces the volume of the gimbal; by adopting the circuit connection method of this embodiment, the camera 1 can achieve 360-degree rotation without dead angles, and can rotate infinitely and continuously around the axis of the conductive slip ring 9 without limitation.

[0056] This embodiment adopts a micro-reduction stepping motor, and utilizes a reduction group and a worm gear transmission to achieve rotation in two directions without placing the motor vertically. At the same time, a conductive slip ring is used to achieve continuous rotation of the upper drive structure, thereby reducing the size and improving the flexibility of the pan / tilt head.

[0057] Embodiment 2

[0058] This embodiment provides a control method for a two-axis gimbal 100 of a drone according to Embodiment 1, comprising the following steps:

[0059] The pwm1 signal output by the receiver is connected to the IO1 port of the STM32 main control chip as an input signal;

[0060] Determine the sign of pwm1-1500. If it is positive, configure the IO2 port dir1 of the STM32 main control chip to 1. Otherwise, output dir1 to 0.

[0061] Select the proportional coefficient k1 and configure the IO3 port of the STM32 main control chip to output the square wave signal step1, whose frequency is determined by k1|pwm1-1500|;

[0062] Connect the IO2 port and IO3 port to the dir1 and step1 ports of a TMC2209 driver chip respectively;

[0063] A TMC2209 driver chip converts the input dir1 and step1 signals into A+, A-, B+, B-, and connects to the lower drive structure 13 through a conductive slip ring 9;

[0064] At the same time, the pwm2 signal output by the receiver is connected to the IO4 port of the STM32 main control chip as an input signal;

[0065] Determine the sign of pwm2-1500. If it is positive, configure the IO5 port of the STM32 main control chip to dir2=1. Otherwise, output dir2=0.

[0066] Select the proportional coefficient k2, configure the IO6 port of the STM32 main control chip to output the square wave signal step2, and its frequency is determined by k2|pwm2-1500|;

[0067] Connect the IO5 port and IO6 port to the dir2 and step2 ports of another TMC2209 driver chip respectively;

[0068] Another TMC2209 driver chip converts the input dir2 and step2 signals into C+, C-, D+, D-, and connects to the lower-layer driver structure 13.

[0069] In this embodiment, the pwm1 and pwm2 signals may be set with dead zone protection to prevent the two-axis gimbal 100 of the drone from malfunctioning.

[0070] This embodiment can realize remote control, and can also realize precise angle control according to the gear reduction ratio and the proportional coefficient set by the program.

[0071] The present specification uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A control method for a two-axis gimbal of a UAV, Features: The two-axis gimbal of a drone comprises a bracket, a camera, an upper driving structure, a lower driving structure and a conductive slip ring, wherein the camera is arranged on the bracket, the camera is rotatably connected to the bracket, the upper driving structure drives the camera to rotate around a first axis, the wires of the camera and the wires of the upper driving structure are both connected to the conductive slip ring, the rotating end of the conductive slip ring is connected to the lower driving structure and the bracket, the lower driving structure drives the camera to rotate around a second axis, the upper driving structure and the lower driving structure are both horizontally arranged, and the first axis is perpendicular to the second axis; It also includes a lower circuit board, the lower circuit board includes a signal conversion module and an image transmission module, the signal conversion module is provided with a pwm1 input terminal, a pwm2 input terminal, a V input terminal, a G input terminal, an A+ output terminal, an A- output terminal, a B+ output terminal, a B- output terminal, a C+ output terminal, a C- output terminal, a D+ output terminal and a D- output terminal, the image transmission module is provided with a V output terminal, a G output terminal and an S output terminal, the V output terminal, the G output terminal and the S output terminal of the image transmission module are connected to the camera through the conductive slip ring, the A+ output terminal, the A- output terminal, the B+ output terminal and the B- output terminal of the signal conversion module are connected to the upper drive structure through the conductive slip ring, and the C+ output terminal, the C- output terminal, the D+ output terminal and the D- output terminal of the signal conversion module are connected to the lower drive structure; The signal conversion module includes a main control chip and two driver chips. The main control chip receives pwm1 and pwm2 signals respectively through two IO ports. After the pwm1 and pwm2 signals pass through the signal conversion program, they drive the upper-layer driver structure and the lower-layer driver structure respectively through one of the driver chips. The control method of the two-axis gimbal of a drone includes the following steps: The pwm1 signal output by the receiver is connected to the IO1 port of the main control chip as an input signal; Determine the sign of pwm1-1500. If it is positive, configure the IO2 port dir1 of the main control chip to 1. Otherwise, output dir1 to 0. Select the proportional coefficient k1 and configure the IO3 port of the main control chip to output the square wave signal step1, whose frequency is determined by k1|pwm1-1500|; Connect the IO2 port and the IO3 port to the dir1 port and step1 port of a driver chip respectively; A driver chip converts the input dir1 and step1 signals into A+, A-, B+, B-, and connects them to the lower drive structure through a conductive slip ring; At the same time, the pwm2 signal output by the receiver is connected to the IO4 port of the main control chip as an input signal; Determine the sign of pwm2-1500. If it is positive, configure the IO5 port of the main control chip to dir2=1. Otherwise, output dir2=0. Select the proportional coefficient k2 and configure the IO6 port of the main control chip to output the square wave signal step2, whose frequency is determined by k2|pwm2-1500|; Connect the IO5 port and IO6 port to the dir2 and step2 ports of another driver chip respectively; Another driver chip converts the input dir2 and step2 signals into C+, C-, D+, and D-, and connects them to the lower-level driver structure.

2. The control method of the two-axis gimbal of a drone according to claim 1, Features: It also includes a camera cover, an output gear and an upper gear, wherein the upper driving structure is arranged on the camera cover, the camera is connected to the camera cover, the upper gear is connected to the bracket, the output gear is arranged on the output shaft of the upper driving structure, the output gear is meshed with the upper gear, and the upper driving structure drives the output gear to rotate, thereby driving the camera and the camera cover to rotate around the first axis.

3. The control method of the two-axis gimbal of a drone according to claim 2, Features: The camera cover is provided with a first through hole, the body of the upper driving structure is connected to the camera cover, and the output shaft of the upper driving structure passes through the first through hole; second through holes are respectively provided on both sides of the camera cover, and connecting holes corresponding to the second through holes are respectively provided on both sides of the camera, and mounting holes corresponding to the second through holes are provided on the bracket, and a first bearing is provided in each of the mounting holes, and a screw passes through the first bearing, the upper gear, the second through hole and the connecting hole in sequence, and the camera cover and the camera are rotatably connected to the bracket through the first bearing.

4. The control method of the two-axis gimbal of a drone according to claim 1, Features: It also includes a turntable and a chassis, wherein the turntable is arranged above the chassis and is rotatably connected to the chassis, the bracket is arranged on the turntable, the fixed ends of the lower driving structure and the conductive slip ring are both arranged on the chassis, the rotating end of the conductive slip ring is connected to the turntable, and the turntable is provided with wire holes for the wires of the camera and the wires of the upper driving structure to pass through.

5. The control method of the two-axis gimbal of a drone according to claim 4, Features: It also includes a worm, a lower gear and a driving gear, wherein the worm is arranged on the output shaft of the lower driving structure, the lower gear is arranged on the chassis, the driving gear is sleeved on the rotating end of the conductive slip ring, the worm is meshed with the lower gear, the lower gear is meshed with the driving gear, and the lower driving structure drives the worm to rotate, thereby driving the lower gear, the driving gear, the conductive slip ring and the camera to rotate around the second axis.

6. The control method of the two-axis gimbal of a drone according to claim 5, Features: A fixing hole is provided at the bottom of the chassis, and the fixed end of the conductive slip ring is arranged in the fixing hole; a through hole for the image transmission antenna is opened on the side wall of the chassis for the image transmission antenna to pass through; the lower driving structure is arranged on the base on the chassis, and the lower gear is rotatably connected to the mounting base on the chassis.

7. The control method of the two-axis gimbal of a drone according to claim 1, Features: The upper driving structure and the lower driving structure are both reduction stepping motors.

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