Agricultural multipurpose robot based on RGB-D camera

Abstract

The agricultural multipurpose robot based on the RGB-D camera comprises a fixed base, supporting rods are fixedly connected to the positions, close to the four corners, of the top of the fixed base, a table top plate is fixedly connected between the top ends of the four supporting rods, and a mechanical arm control mechanism is fixedly arranged at the position, close to the center, of the top of the table top plate; the RGB-D camera is used for recognizing and positioning the top end of target cotton, a command is sent to the laser engraving module, laser is emitted at the focus position right in front of the top end of the cotton so as to accurately process the top end of the cotton, the RGB-D camera and the six-axis control mechanical arm work cooperatively, effective obstacle avoidance of an execution mechanism in a cotton field is achieved, and the work efficiency is improved. And after laser emission is stopped, the RGB-D camera carries out cotton top end identification again, and when no redundant top end exists in the visual field, the execution mechanism carries out reset and calibration operation.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural robots, in particular to an agricultural multi-purpose robot based on an RGB-D camera. Background Art

[0002] As one of the most important economic crops in the world, cotton fiber is not only an indispensable basic material for the textile industry, but cotton seeds can also be used for oil extraction and processing of various by-products, which plays an irreplaceable role in ensuring national food security and promoting farmers' income. As the world's largest cotton producer, China shoulders the important responsibility of ensuring the stability of domestic cotton supply. In order to further improve the economic benefits of cotton planting, it is necessary to pay attention not only to the yield of cotton, but also to the quality of cotton, because this is directly related to the market competitiveness and added value of the final product. In the cotton growth cycle, spring is the key period that determines the annual yield and quality of cotton, and topping is the top priority. Timely and accurate topping can effectively regulate the nutrient distribution of cotton plants, prompting more nutrients to flow to the flower and boll parts, thereby significantly increasing the number of bolls, improving the quality of cotton bolls, reducing the formation of ineffective flower buds, and avoiding waste of resources. In addition, correct topping technology can also improve the ventilation and light transmission conditions in the field, reduce the incidence of diseases and pests, and thus comprehensively improve the quality of cotton.

[0003] In traditional cotton topping operations, it relies on the on-site guidance of professional plant protection personnel and the input of a large amount of manual labor, which not only makes the operation inefficient, but also greatly increases production costs. Especially when faced with vast cotton fields, traditional methods are difficult to meet the timeliness and accuracy requirements of modern agriculture. In addition, the field environment is complex and changeable, and cotton plants often block each other. Coupled with the uncertainty of lighting conditions, the positioning of the machine vision system has brought considerable challenges. The complex background and changes in sensor posture have further aggravated the difficulty of target recognition, which can easily lead to misoperation of the main stem. It is impossible to completely overcome the problem of target detection and positioning errors in dynamic environments. The existence of outliers affects the quality and reliability of the overall operation.

[0004] In view of this, we proposed an agricultural multi-purpose robot solution based on RGB-D camera, aiming to completely solve the problems existing in the above-mentioned traditional topping operation. Compared with previous research results, our design not only improves the accuracy of target detection, but also greatly enhances the robustness and adaptability of the system, ensuring stable operation in various environments. Summary of the invention

[0005] The purpose of the present invention is to provide an agricultural multi-purpose robot based on an RGB-D camera, aiming to completely solve the problems existing in the above-mentioned traditional topping operation. This solution innovatively integrates a high-precision RGB-D camera, a six-axis control robot arm and an advanced laser engraving module, realizing an integrated process from target recognition to precise processing. By adopting the RealSense D435 depth camera, the system can obtain high-quality color images and depth information in real time, and can accurately identify the position of the cotton top even in insufficient light or complex background conditions. Compared with previous research results, this design not only improves the accuracy of target detection, but also greatly enhances the robustness and adaptability of the system, ensuring stable operation in various environments.

[0006] More importantly, the present invention utilizes the collaborative work between the RGB-D camera and the six-axis control robot arm to achieve effective obstacle avoidance of the actuator in the cotton field, ensuring that the laser engraving module can safely and accurately reach the top position of each cotton to be processed. This non-contact topping method avoids the physical damage that may be caused by traditional mechanical means and protects the healthy growth of cotton plants. At the same time, the entire process is automatically controlled by an electronic chip controller, which greatly reduces manpower requirements, reduces labor intensity, and significantly improves work efficiency. This solution can effectively reduce operating costs while ensuring the topping effect, providing new technical support for modern agriculture.

[0007] To achieve the above object, the present invention provides the following technical solution: an agricultural multi-purpose robot based on an RGB-D camera, comprising a fixed base, the top of the fixed base is fixedly connected to support rods near four corners, a desktop panel is fixedly connected between the tops of the four support rods, a mechanical arm control mechanism is fixedly arranged near the center of the top of the desktop panel, and the mechanical arm control mechanism includes an electronic chip controller and an operation keyboard;

[0008] An electronic display screen is fixedly installed on the top of the electronic chip controller, an extension plate is fixedly connected to the rear side of the electronic chip controller near the center, a signal conduction controller is fixedly installed on the top of the extension plate near the center, a six-axis control robot is movably installed on the top of the signal conduction controller, a fixed support frame is fixedly connected to the top of the six-axis control robot, a rotating shaft is rotatably connected to the rear side of the fixed support frame, an RGB-D camera is fixedly installed on one end of the rotating shaft, a card slot is provided on one side of the RGB-D camera, a high-definition camera is arranged inside the card slot near the center, and a laser engraving module is fixedly installed on one side of the interior of the RGB-D camera.

[0009] Preferably, a power supply box is fixedly installed on the top edge of the fixed base close to one side, and positive and negative wiring terminals are movably provided on the top edges of the power supply box close to both sides.

[0010] Preferably, the bottom of the fixed base is fixedly connected with shock absorbing rods near the four corners, a fixed chassis is fixedly connected between the bottom ends of the four shock absorbing rods, and the fixed chassis is electrically connected to the positive and negative wiring terminals.

[0011] Preferably, the outer surfaces of the front and rear sides of the fixed chassis are rotatably connected with rotating rods near the edges of both sides and the center of the top through bearings, and one end of the rotating rod is fixedly sleeved with a rotating gear.

[0012] Preferably, a track shock absorption adjustment mechanism is provided on the outer surfaces of both sides of the fixed chassis near the center of the bottom, and the track shock absorption adjustment mechanism includes a plurality of first fixed rods and second fixed rods, one end of the first fixed rod is fixedly connected to a fixed sleeve, and a fixed block is fixedly extended from the outer surface of one side of the fixed sleeve.

[0013] Preferably, one end of the second fixing rod is fixedly and rotatably connected to a rotating sleeve, an outer surface of the rotating sleeve is fixedly connected to an extended fixing plate, and one end of the extended fixing plate is rotatably connected to a rolling wheel via a rotating shaft.

[0014] Preferably, a U-shaped block is fixedly connected to the edge of one side near the top of the extended fixed plate, a rotating shaft is rotatably connected between the inner surface walls on the opposite side of the U-shaped block, a shock absorber is fixedly welded to the outer surface of the rotating shaft near the center, and a limiting block is fixedly connected to the top of the shock absorber.

[0015] Preferably, a shock absorbing spring is sleeved on the outer surface of the shock absorber, and one end of the shock absorbing spring is welded to the outer surface of the rotating shaft, and the other end of the shock absorbing spring is welded to the bottom of the limiting block, and a connecting shaft is fixedly connected to the top of the limiting block near the center, and one end of the connecting shaft is rotatably connected to the fixed block via a rotating shaft.

[0016] Preferably, a transmission track is transmission-connected between the rotating gear and the outer surface of the rolling wheel.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Use the RGB-D camera to identify and locate the target cotton top. Send a command to the laser engraving module to emit laser at the focal position just in front of the cotton top to accurately process the cotton top. The RGB-D camera and the six-axis control robot work together to achieve effective obstacle avoidance for the actuator in the cotton field, so that the laser engraving module at the end of the actuator moves to the position to be toppled. After the laser stops emitting, the RGB-D camera identifies the cotton top again. When there are no extra tops in the field of view, the actuator performs reset and calibration operations.

[0019] 2. The main stem, top, branches and leaves of cotton and the background of the ground are quite different. The top has a strong distinguishable color feature, and its position information can better reflect the spatial position of the top itself, which is helpful for the visual system to identify and locate the top. Considering the complex light environment, many obstacles and short recognition distance inside the cotton field, the RGB-D camera is composed of D400 visual processor, ISP color image signal processor and optical depth processing module. It also has USB power supply and external sensor data interface, which is convenient for user operation and secondary development. The D435 depth camera has the advantages of small size, low power consumption and high precision, so this depth camera is used in the research and development of this project;

[0020] 3. As a high-precision processing equipment, the laser engraving module is often used for engraving, cutting or marking of various conventional materials. Due to the high energy and accuracy of the laser beam, the laser engraving module can achieve high-precision processing effects, which is very useful for application scenarios that require fine processing. Since the distance between the main stem and the top of the cotton is relatively small, if mechanical equipment is used to remove the top, collision accidents are prone to occur during the process of thinning flowers and fruits, which may cause significant interference to the surrounding main stems. Such a situation is not conducive to the topping operation of the machine based on visual navigation. Therefore, a laser device relying on visual guidance is used for topping operations and improves the execution efficiency of the actuator;

[0021] 4. The transmission track can travel on cotton field terrain or on concrete floors. The fixed chassis, visual system RGB-D camera and six-axis control robot are all controlled by the electronic chip controller of the system. By controlling the rotating rod to rotate, the rotating rod will drive the rotating gear to rotate, and then the transmission track will move. In the process of further driving the transmission track, the rolling wheel will be partially squeezed, so that the extended fixed plate will drive the rotating sleeve to rotate. The setting of the shock absorber makes it easy for the device to effectively absorb shock. After the shock absorbing spring absorbs shock, it has a certain recovery effect, which makes it easy for the equipment to effectively recover. By adjusting the connecting shaft and the rotating shaft, the shock absorber can be adjusted in angle, so that the device can effectively absorb shock. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a front stereoscopic image of the agricultural multi-purpose robot based on the RGB-D camera of the present invention;

[0023] Figure 2 A side stereogram of the agricultural multi-purpose robot based on an RGB-D camera of the present invention;

[0024] Figure 3 A top-down stereogram of the agricultural multi-purpose robot based on an RGB-D camera of the present invention;

[0025] Figure 4 This is a structural stereogram of the main view of the six-axis control mechanical arm of the agricultural multi-purpose robot based on the RGB-D camera of the present invention;

[0026] Figure 5 It is a schematic diagram of the side view structure of the six-axis control mechanical arm of the agricultural multi-purpose robot based on the RGB-D camera of the present invention;

[0027] Figure 6 It is a partial structural schematic diagram of the crawler shock absorption adjustment mechanism of the agricultural multi-purpose robot based on the RGB-D camera of the present invention;

[0028] Figure 7 The present invention is an agricultural multi-purpose robot based on RGB-D camera Figure 6 Schematic diagram of the structure at point A in the middle.

[0029] In the figure:

[0030] 1. Fixed base; 2. Support rod; 3. Desktop panel; 4. Power box; 5. Positive and negative terminals; 6. Electronic chip controller; 7. Electronic display screen; 8. Extension board; 9. Signal conduction controller; 10. Six-axis control robot; 11. Fixed support frame; 12. Rotating shaft; 13. RGB-D camera; 14. Card slot; 15. Laser engraving module; 16. Operation keyboard; 17. Shock absorber rod; 18. Fixed chassis; 19. Rotating rod; 20. Rotating gear; 21. First fixed rod; 22. Fixed sleeve; 23. Second fixed rod; 24. Rotating shaft sleeve; 25. Extended fixed plate; 26. U-shaped block; 27. Rotating shaft rod; 28. Shock absorber; 29. ​​Shock absorber spring; 30. Limit block; 31. Fixed block; 32. Connecting shaft; 33. Rolling wheel; 34. Drive track; 35. High-definition camera. DETAILED DESCRIPTION

[0031] 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 implementation regulations described 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.

[0032] See also Figure 1-7 The present invention provides a technical solution: an agricultural multi-purpose robot based on an RGB-D camera, comprising a fixed base 1, a support rod 2 is fixedly connected to the top of the fixed base 1 near four corners, a desktop board 3 is fixedly connected between the tops of the four support rods 2, a mechanical arm control mechanism is fixedly arranged near the center of the top of the desktop board 3, the mechanical arm control mechanism includes an electronic chip controller 6 and an operation keyboard 16, an electronic display screen 7 is fixedly installed on the top of the electronic chip controller 6, an extension plate 8 is fixedly connected to the rear side of the electronic chip controller 6 near the center, and the extension plate 8 A signal conduction controller 9 is fixedly installed near the center of the top, a six-axis control robot 10 is movably installed on the top of the signal conduction controller 9, a fixed support frame 11 is fixedly connected to the top of the six-axis control robot 10, a rotating shaft 12 is rotatably connected to the rear side of the fixed support frame 11, an RGB-D camera 13 is fixedly installed on one end of the rotating shaft 12, a card slot 14 is provided on one side of the RGB-D camera 13, a high-definition camera 35 is arranged inside the card slot 14 near the center, and a laser engraving module 15 is fixedly installed on one side of the inside of the RGB-D camera 13.

[0033] A power supply box 4 is fixedly mounted on the top edge of the fixed base 1 near one side, and positive and negative wiring terminals 5 are movably arranged on the top edges of the power supply box 4 near both sides.

[0034] The bottom of the fixed base 1 is fixedly connected with shock absorbing rods 17 near the four corners, and a fixed chassis 18 is fixedly connected between the bottom ends of the four shock absorbing rods 17, and the fixed chassis 18 is electrically connected to the positive and negative wiring terminals 5.

[0035] The outer surfaces of the front and rear sides of the fixed chassis 18 are rotatably connected to rotating rods 19 near the edges of both sides and the center of the top through bearings, and one end of the rotating rods 19 is fixedly sleeved with a rotating gear 20.

[0036] A track shock-absorbing adjustment mechanism is provided on the outer surfaces of both sides of the fixed chassis 18 near the center of the bottom. The track shock-absorbing adjustment mechanism includes a plurality of first fixing rods 21 and second fixing rods 23. One end of the first fixing rod 21 is fixedly connected to a fixing sleeve 22, and a fixing block 31 is fixedly extended from the outer surface of one side of the fixing sleeve 22.

[0037] One end of the second fixing rod 23 is fixedly and rotatably connected to a rotating sleeve 24 , an outer surface of the rotating sleeve 24 is fixedly connected to an extending fixing plate 25 , and one end of the extending fixing plate 25 is rotatably connected to a rolling wheel 33 via a rotating shaft.

[0038] A U-shaped block 26 is fixedly connected to the edge of one side of the top of the extended fixed plate 25, a rotating shaft 27 is rotatably connected between the inner surface wall on the opposite side of the U-shaped block 26, a shock absorber 28 is fixedly welded to the outer surface of the rotating shaft 27 near the center, and a limiting block 30 is fixedly connected to the top of the shock absorber 28.

[0039] A shock absorbing spring 29 is sleeved on the outer surface of the shock absorber 28, and one end of the shock absorbing spring 29 is welded to the outer surface of the rotating shaft 27, and the other end of the shock absorbing spring 29 is welded to the bottom of the limiting block 30. A connecting shaft 32 is fixedly connected to the top of the limiting block 30 near the center, and one end of the connecting shaft 32 is rotatably connected to the fixed block 31 through a rotating shaft.

[0040] A transmission track 34 is transmission-connected between the rotating gear 20 and the outer surface of the rolling wheel 33 .

[0041] Working principle of this embodiment: When the device is used, the RGB-D camera 13 is first used to identify and locate the target cotton top, and a command is sent to the laser engraving module 15 to emit laser at the focal position just in front of the cotton top to accurately process the cotton top. The RGB-D camera 13 and the six-axis control robot 10 work together to achieve effective obstacle avoidance of the actuator in the cotton field, so that the laser engraving module 15 at the end of the actuator moves to the position to be toppled. After the laser stops emitting, the RGB-D camera 13 identifies the cotton top again. When there is no extra top in the field of view, the actuator performs reset and calibration operations, that is, a topping operation is completed;

[0042] The main stem, top, branches and leaves of cotton and the background composed of the ground are quite different. The top has a strong distinguishable color feature, and its position information can better reflect the spatial position of the top itself, which is helpful for the visual system to identify and locate the top. Considering the complex light environment, many obstacles and short recognition distance inside the cotton field, this study uses the structured light depth camera D435 as the experimental recognition and positioning device. The RealSense series is a highly intelligent depth information perception camera developed by Intel. The RealSense D435 is widely used in industry, agriculture and military fields. The D435 depth camera is from left to right: left infrared camera (IR Stereo), infrared dot matrix laser transmitter (IRProjector), right infrared camera and RGB sensor. The infrared camera module is mainly used to collect depth information in the surrounding environment, and the processing of RGB image information is mainly completed by the RGB sensor. The built-in system of the D435 camera consists of the D400 visual processor, ISP color image signal processor and optical depth processing module. It also has a USB power supply and external sensor data interface to facilitate user operation and secondary development. The D435 depth camera has the advantages of small size, low power consumption and high precision, so this depth camera is used in the research and development of this project;

[0043] As a high-precision processing equipment, the laser engraving module 15 is commonly used for engraving, cutting or marking various conventional materials. Due to the high energy and accuracy of the laser beam, the laser engraving module 15 can achieve high-precision processing effects, which is very useful for application scenarios that require fine processing. Since the distance between the main stem and the top of the cotton is relatively small, if mechanical equipment is used to remove the top, collision accidents are prone to occur during the process of thinning flowers and fruits, which may cause significant interference to the surrounding main stems. Such a situation is not conducive to the topping operation of the machine based on visual navigation, so a laser device relying on visual guidance is used for topping operations, and the execution efficiency of the actuator is improved;

[0044] The transmission crawler 34 can travel on orchard terrain such as cotton fields, or on concrete floors. The fixed chassis 18, the visual system RGB-D camera 13 and the six-axis control robot 10 are all controlled by the electronic chip controller 6 of the system. By controlling the rotation of the rotating rod 19, the rotating rod 19 will drive the rotating gear 20 to rotate, and then the transmission crawler 34 will move and travel. In the process of the transmission crawler 34 traveling, the rolling wheel 33 will be partially squeezed, so that the extended fixed plate 25 will drive the rotating sleeve 24 to rotate. The setting of the shock absorber 28 makes it easy for the device to effectively reduce shock. After the shock absorption of the shock absorbing spring 29, it has a certain recovery effect, which makes it easy for the equipment to be effectively restored. By adjusting the connecting shaft 32 and the rotating shaft rod 27, the shock absorber 28 is adjusted in angle, so that the device is easy to achieve effective shock absorption effect.

[0045] The color image acquired by the RGB-D camera 13 is loaded into the electronic chip controller 6, and the running target detection network determines whether the acquired image contains the main stem. If the main stem is identified, the left and right infrared cameras will match the depth of the main stem through the parallax of the left and right views, and calculate the depth D1 of the main stem by the focal length, baseline length and parallax. The electronic chip controller 6 reads the scale inside the RGB-D camera 13 and compares it with the distance D2 moved by the depth camera carried by the end of the actuator on the depth coordinate axis to obtain the proportional coefficient α. After the identified main stem area is marked with a rectangular bounding box, it is proportionally scaled to D2 in front of the depth camera using the proportional coefficient α as the identification area for top detection to achieve mapping from the main stem area to the top area. Subsequently, the depth camera carried by the end of the actuator moves a distance D2 on the depth coordinate axis, and the obtained color image is loaded into the main control board. The target detection network determines whether there is a top with a confidence greater than a set threshold in the top detection area. If so, the depth D1 at this time is calculated, and the position coordinates of the top centroid in the color image are returned;

[0046] The coordinates of the above-obtained 5 consecutive frames of images are calculated in turn with the coordinates of the initial frame on their corresponding coordinate axes for relative errors. If the relative errors of the top centroid positioning coordinates in n consecutive frames meet the set error threshold, the coordinates of the above n frames are averaged on their respective coordinate axes to obtain the average positioning coordinates of the top centroid. The coordinates of the main stem and the top are published in ROS relative to the RGB-D camera 13 coordinate system. The published coordinates are relative to the six-axis control robot 10 coordinate system. The camera coordinate system and the world coordinate system (the centroid of the bottom of the robot) are converted through the TF library. The converted quaternion matrix can update the conversion matrix between the RGB-D camera 13 coordinate system and the world coordinate system in real time. This method relies on the URDF simulation model of the robot established in advance. The rotation angle of each motor in the robot is read through the joint_states topic in ROS, and the relevant parameters of the URDF state and the conversion matrix are updated in real time, thereby minimizing the posture error.

[0047] In this technical solution, the power box 4, the electronic chip controller 6, the signal transmission controller 9 and the six-axis control robot arm 10 are all existing technologies and will not be elaborated in detail here.

[0048] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An agricultural multi-purpose robot based on an RGB-D camera, comprising a fixed base (1), characterized in that: The top of the fixed base (1) is fixedly connected to support rods (2) near the four corners, a desktop panel (3) is fixedly connected between the top ends of the four support rods (2), and a mechanical arm control mechanism is fixedly arranged near the center of the top of the desktop panel (3), and the mechanical arm control mechanism includes an electronic chip controller (6) and an operating keyboard (16); An electronic display screen (7) is fixedly installed on the top of the electronic chip controller (6); an extension plate (8) is fixedly connected to the rear side of the electronic chip controller (6) near the center; a signal conduction controller (9) is fixedly installed on the top of the extension plate (8) near the center; a six-axis control robot (10) is movably installed on the top of the signal conduction controller (9); a fixed support frame (11) is fixedly connected to the top of the six-axis control robot (10); a rotating shaft (12) is rotatably connected to the rear side of the fixed support frame (11); an RGB-D camera (13) is fixedly installed on one end of the rotating shaft (12); a card slot (14) is provided on one side of the RGB-D camera (13); a high-definition camera (35) is arranged inside the card slot (14) near the center; and a laser engraving module (15) is fixedly installed on one side of the interior of the RGB-D camera (13).

2. The agricultural multi-purpose robot based on RGB-D camera according to claim 1, characterized in that: A power supply box (4) is fixedly mounted on the top of the fixed base (1) near one edge, and positive and negative wiring terminals (5) are movably arranged on the top of the power supply box (4) near two edges.

3. The agricultural multi-purpose robot based on RGB-D camera according to claim 1, characterized in that: The bottom of the fixed base (1) is fixedly connected to shock absorbing rods (17) near the four corners, and a fixed chassis (18) is fixedly connected between the bottom ends of the four shock absorbing rods (17), and the fixed chassis (18) is electrically connected to the positive and negative wiring terminals (5).

4. The agricultural multi-purpose robot based on RGB-D camera according to claim 3, characterized in that: The front and rear outer surfaces of the fixed chassis (18) are rotatably connected to a rotating rod (19) near the edges of both sides and the center of the top through bearings, and one end of the rotating rod (19) is fixedly sleeved with a rotating gear (20).

5. The agricultural multi-purpose robot based on RGB-D camera according to claim 3, characterized in that: A track damping adjustment mechanism is provided at the center of the bottom of the outer surfaces of both sides of the fixed chassis (18), and the track damping adjustment mechanism comprises a plurality of first fixing rods (21) and second fixing rods (23), one end of the first fixing rod (21) is fixedly connected to a fixing sleeve (22), and a fixing block (31) is fixedly extended from the outer surface of one side of the fixing sleeve (22).

6. The agricultural multi-purpose robot based on RGB-D camera according to claim 5, characterized in that: One end of the second fixing rod (23) is fixedly and rotatably connected to a rotating shaft sleeve (24), an outer surface of the rotating shaft sleeve (24) is fixedly connected to an extending fixing plate (25), and one end of the extending fixing plate (25) is rotatably connected to a rolling wheel (33) via a rotating shaft.

7. The agricultural multi-purpose robot based on RGB-D camera according to claim 6, characterized in that: A U-shaped block (26) is fixedly connected to the edge of one side of the top of the extended fixed plate (25); a rotating shaft (27) is rotatably connected between the inner surface walls on the opposite side of the U-shaped block (26); a shock absorber (28) is fixedly welded to the outer surface of the rotating shaft (27) near the center; and a limiting block (30) is fixedly connected to the top of the shock absorber (28).

8. The agricultural multi-purpose robot based on RGB-D camera according to claim 7, characterized in that: A shock absorbing spring (29) is sleeved on the outer surface of the shock absorber (28), and one end of the shock absorbing spring (29) is welded to the outer surface of the rotating shaft (27), and the other end of the shock absorbing spring (29) is welded to the bottom of the limiting block (30). A connecting shaft (32) is fixedly connected to the top of the limiting block (30) near the center, and one end of the connecting shaft (32) is rotatably connected to the fixed block (31) via a rotating shaft.

9. The agricultural multi-purpose robot based on RGB-D camera according to claim 4 or 6, characterized in that: A transmission track (34) is transmission-connected between the rotating gear (20) and the outer surface of the rolling wheel (33).

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