Tree climbing mechanical hand for high altitude fruit picking and working method thereof

Abstract

The application discloses a tree-climbing mechanical hand for high-altitude fruit picking and a working method thereof, and solves the problem that a mechanical hand cannot move along the direction of a branch and can only pick a single fruit at a time in the prior art, and has the beneficial effect that the mechanical hand can move along the direction of the branch and pick multiple fruits at the same time, and the specific scheme is as follows: a tree-climbing mechanical hand for high-altitude fruit picking comprises a shell, the shell can be connected with a mechanical arm, the shell is provided with a fixed gripper, the shell is movably provided with a sliding gripper, so that the position of the sliding gripper relative to the fixed gripper can be adjusted, the fixed gripper and the sliding gripper can be opened and closed, the fixed gripper and the sliding gripper can be sleeved on a branch when being closed, the fixed gripper can clamp the branch when sleeving the branch, the area formed after the sliding gripper is closed is greater than the area formed after the fixed gripper is closed, and the sliding gripper can move along the branch when sleeving the branch.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to a tree-climbing robotic arm for high-altitude fruit harvesting and its working method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] With the continuous expansion of fruit tree planting, the demand for harvesting fruits grown at height (such as pine cones and walnuts) is increasing. To improve harvesting efficiency and reduce labor costs, harvesting robots, as important intelligent equipment for fruit harvesting operations, have been widely researched and initially applied. However, existing harvesting robots are mostly designed for orchards, and their structures are generally suitable for flat terrain and moderately sized fruit trees, making it difficult to meet the actual needs of harvesting fruits at height.

[0004] Specifically, existing harvesting robots generally have the following drawbacks: First, most of the equipment lacks the ability to climb independently and cannot move along the direction of the branches; Secondly, the harvesting of individual fruits by a single robotic arm results in low overall efficiency. In other words, robotic arms are mostly used for single-point operations in practical applications, with weak continuous and multi-target processing capabilities.

[0005] Third, existing robotic arms rely on external cameras to locate fruits, which results in low recognition accuracy and a low level of intelligent operation.

[0006] In summary, existing harvesting robots have significant shortcomings in terms of structural adaptability, recognition accuracy, and operational intelligence, making it difficult to meet the demand for efficient, safe, and reliable harvesting of fruits from high altitudes in complex environments such as forest areas.

[0007] Therefore, there is an urgent need to develop a tree-climbing picking robot to solve the key technical bottlenecks currently faced in high-altitude fruit picking operations in forestry. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the purpose of this invention is to provide a tree-climbing robotic arm for high-altitude fruit harvesting, which has the ability to climb tree trunks autonomously, is highly adaptable, and has a high degree of intelligence.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solution: A tree-climbing robotic arm for high-altitude fruit harvesting includes a housing that can be connected to a robotic arm. The housing is equipped with a fixed gripper and a movable sliding gripper, allowing the position of the sliding gripper relative to the fixed gripper to be adjustable. Both the fixed and sliding grippers can open and close. When closed, the fixed and sliding grippers can clamp onto a branch. When clamping onto a branch, the fixed gripper clamps the branch tightly. The area formed by the closed sliding gripper is larger than the area formed by the closed fixed gripper. When clamping onto a branch, the sliding gripper can move along the branch and can touch at least one fruit during the movement to harvest the fruit.

[0010] As described above, a tree-climbing robotic arm for high-altitude fruit picking includes two opposing grippers in both the fixed gripper and the sliding gripper. The two grippers of the fixed gripper and the sliding gripper are hinged together, and the bottom end of each gripper is slidable relative to the outer shell. The plane where the fixed clamp is located is parallel to the plane where the sliding clamp is located, and the area of ​​the fixed clamp and the sliding clamp after they are closed is greater than the longitudinal cross-sectional area of ​​the tree branch.

[0011] As described above, a tree-climbing robotic arm for high-altitude fruit harvesting has a housing with a fixed end platform and a sliding platform. The sliding platform is connected to a linear drive mechanism, which is fixed to the housing. The fixed end platform and the sliding platform are each provided with an open slot. The bottom of the fixed gripper is rotatably mounted in the open slot of the fixed end platform, and the bottom of the sliding gripper is rotatably mounted in the open slot of the sliding platform.

[0012] As described above, a tree-climbing robotic arm for high-altitude fruit harvesting has a sliding groove on the side wall of the open slot. Connectors are respectively provided at the bottom ends of the fixed gripper and the sliding gripper. One connector is rotatably mounted on the side wall of the open slot, while the other connector passes through the sliding groove to restrict the linear movement of the fixed and sliding grippers. After passing through the sliding groove, the connector connects to a crank-rocker assembly, which is mounted on the housing. The closing position of the fixed and sliding grippers is limited by the distance the crank-rocker assembly moves along the sliding groove.

[0013] As described above, in a tree-climbing robotic arm for high-altitude fruit harvesting, the two crank-rocker assemblies are positioned between the fixed gripper and the sliding gripper. The linear drive mechanism is a lead screw and nut mechanism. The power source of the lead screw and nut mechanism is located inside the housing. The lead screw and nut mechanism includes a lead screw, a lead screw nut, and a slide table. The slide table supports the sliding platform. Corrugated protective sleeves are respectively provided on both sides of the lead screw and nut in the circumferential direction.

[0014] As described above, a tree-climbing robotic arm for high-altitude fruit picking includes a fixed gripper comprising a double-layer gripper plate and a single-layer gripper plate arranged opposite each other. The double-layer gripper plate has a groove in the middle, and when the double-layer gripper plate and the single-layer gripper plate are closed, the single-layer gripper plate can enter the groove of the double-layer gripper plate. Both the double-layer and single-layer gripper plates are bent.

[0015] As described above, a tree-climbing robotic arm for high-altitude fruit harvesting has a resistance-increasing component on the inner side of the double-layer gripper and the single-layer gripper to stably grip the tree branch. The resistance-increasing component is located in the lower half of the double-layer gripper and the single-layer gripper.

[0016] As described above, a tree-climbing robotic arm for high-altitude fruit harvesting includes a sliding gripper comprising two opposing circular grippers that are staggered and in contact when closed, and the circular grippers are arc-shaped.

[0017] As described above, a tree-climbing robotic arm for high-altitude fruit picking has a protrusion on its outer shell for connection with the robotic arm. A camera and a laser rangefinder are mounted on one side of the outer shell. The laser emitted by the laser rangefinder is parallel to the plane of the fixed gripper. The laser rangefinder is positioned to one side of the camera. The robotic arm and the laser rangefinder are connected to a controller, and the camera and the controller are connected to a computing terminal. Both the crank rocker assembly and the linear drive mechanism are connected to the controller.

[0018] Secondly, the present invention also provides a method for operating a tree-climbing robotic arm for high-altitude fruit harvesting, comprising the following: The camera sends the captured image data to the computing terminal, which identifies the fruit and sends the identified fruit's location information to the controller. The controller then uses a laser rangefinder to obtain the distance between the robotic arm and the fruit. The controller adjusts the movement of the robotic arm based on the fruit's position information and the distance between the robotic arm and the fruit, so that the sliding gripper moves to the side of the fruit and gets closer to the fruit relative to the fixed gripper. When the laser rangefinder detects that the distance between the robotic arm and the tree branch is within a suitable range, the controller controls the crank-slider assembly to move and drive the fixed gripper and sliding gripper to close and engage the tree branch. The controller controls the linear drive mechanism to move the sliding gripper toward the fruit, thereby detaching the fruit from the branch and harvesting it.

[0019] The beneficial effects of the present invention are as follows: 1) The robotic arm in this invention has a reasonable structure. The robotic arm includes a fixed gripper and a sliding gripper. When the fixed gripper clamps the branch, the sliding gripper can move along the branch to harvest the fruit. This allows the tree-climbing harvesting robotic arm to move along the branch, which helps to overcome the limitation of working height and is especially suitable for harvesting fruits at high altitudes.

[0020] 2) Compared with traditional harvesting robots that can only pick one fruit at a time, the tree-climbing harvesting robot of this invention uses a sliding gripper that simply engages with the branch but can move along the direction of the branch. During the movement, the sliding gripper contacts at least one fruit, allowing one or more fruits such as pine cones to be picked at once, which significantly improves harvesting efficiency.

[0021] 3) In this invention, the fixed gripper and the sliding gripper each include two grippers. The fixed gripper has a double-layer gripper plate and a single-layer gripper plate, and a resistance-increasing component is provided to effectively stabilize the gripper on the branch and avoid damaging the branch. The sliding gripper is easy to move. The sliding gripper includes two circular grippers, which facilitates the whole thing to slide along the branch. The area of ​​the sliding gripper after it is closed is reasonably set so that the fruit can be harvested effectively during the movement.

[0022] 4) In this invention, the outer shell is equipped with a camera and a laser rangefinder sensor, which allows the tree-climbing picking robot to autonomously locate the position of the fruit and branches, reducing the labor intensity of manual tree climbing, alleviating high-intensity physical labor, and reducing the demand for skilled picking workers.

[0023] 5) The overall structure of this invention is reasonably arranged. The fixed gripper and the sliding gripper are effectively connected by a linear drive mechanism, and the movement of the sliding gripper relative to the fixed gripper is ensured. The structural components cooperate and support each other, making the overall design ingenious and compact. The tree-climbing picking robot can move along the branches, which helps to overcome the limitation of working height. At the same time, it can harvest multiple fruits on the same branch, resulting in high harvesting efficiency. Attached Figure Description

[0024] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0025] Figure 1 This is a schematic diagram of a tree-climbing robotic arm for high-altitude fruit harvesting according to one or more embodiments of the present invention.

[0026] Figure 2 This is an internal perspective view of a tree-climbing robotic arm for high-altitude fruit harvesting according to one or more embodiments of the present invention.

[0027] Figure 3This is a schematic diagram of the internal structure of the fixed end platform of a tree-climbing robot for high-altitude fruit picking, according to one or more embodiments of the present invention.

[0028] Figure 4 This is a schematic diagram of the internal structure of the sliding platform in a tree-climbing robot for high-altitude fruit harvesting according to one or more embodiments of the present invention.

[0029] Figure 5 This is a schematic diagram of the closing of a tree-climbing robotic arm for high-altitude fruit picking according to one or more embodiments of the present invention.

[0030] Figure 6 This is a schematic diagram of a tree-climbing robotic arm for high-altitude fruit picking, according to one or more embodiments of the present invention, when it closes at a branch.

[0031] Figure 7 This is a schematic diagram of a tree-climbing robotic arm for high-altitude fruit picking according to one or more embodiments of the present invention, after which the sliding gripper moves to the fruit and causes the fruit to detach from the branch.

[0032] Figure 8 This is a schematic diagram of the grooves on the double-layer gripper and single-layer gripper in a tree-climbing robot for high-altitude fruit picking according to one or more embodiments of the present invention.

[0033] Figure 9 This is a schematic diagram of the working process of a tree-climbing robotic arm for high-altitude fruit picking according to one or more embodiments of the present invention.

[0034] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0035] The components include: 1. Outer shell; 2. Narrow, rigid corrugated sponge block; 3. Single-layer gripper plate; 4. Fine lead screw protective sleeve; 5. Coarse lead screw protective sleeve; 6. Support end cap block; 7. Round clamping plate; 8. Sliding cover cylinder; 9. Fixed end cover cylinder; 10. Double-layer gripper plate; 11. Wide, rigid corrugated sponge block; 12. Laser rangefinder sensor; 13. Carrier plate; 14. Camera; 15. Medium-sized stepper motor; 16. Plum blossom coupling; 17. Lead screw; 18. Threaded... 19. Slide table, 20. Support end, 21. Motor mounting plate, 22. Sliding platform, 23. Miniature stepper motor, 24. Fixed end, 25. Fixed end platform, 26. Rocker support ring, 27. Rocker, 28. Bearing, 29. Top pin, 30. Crank, 31. End cap, 32. Fixed gripper, 33. Sliding gripper, 34. Branch, 35. Fruit, 36. Open groove, 37. Slide groove, 38. Adhesive groove. Detailed Implementation

[0036] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. As described in the background section, existing robotic arms cannot move along tree branches and can only harvest a single fruit at a time. To address these technical problems, this invention proposes a tree-climbing robotic arm for high-altitude fruit harvesting.

[0038] Example 1 In a typical embodiment of the present invention, reference is made to Figure 1 As shown, a tree-climbing robotic arm for high-altitude fruit harvesting includes a housing 1, which can be connected to a robotic arm. The housing is equipped with a fixed gripper, and a sliding gripper 33 is movably mounted on the housing 1 so that the position of the sliding gripper 33 relative to the fixed gripper 32 is adjustable. Both the fixed gripper 32 and the sliding gripper 33 can open and close. When closed, the fixed gripper 32 and the sliding gripper 33 can each form a closed space to fit onto a branch 34. When fitting onto a branch, the fixed gripper 32 clamps the branch tightly. When the sliding gripper 33 is closed, the area formed is larger than that formed by the fixed gripper when closed, so as to facilitate the sliding of the sliding gripper relative to the branch. When fitting onto a branch, the sliding gripper 33 can move along the branch 34. During the movement, the sliding gripper 33 can touch at least one fruit 35 to harvest the fruit.

[0039] Specifically, both the fixed gripper 32 and the sliding gripper 33 include two opposing grippers. The two grippers of the fixed gripper and the sliding gripper are hinged together. The bottom end of each gripper is slidable relative to the outer shell 1. The plane where the fixed gripper is located is parallel to the plane where the sliding gripper is located. The area of ​​the fixed gripper 32 and the sliding gripper 33 after closing is greater than the longitudinal cross-sectional area of ​​the branch 34. Moreover, the width of the enclosed space after the sliding gripper 33 is closed is greater than the diameter of the branch 34 to avoid damaging the branch 34 during the movement of the sliding gripper.

[0040] In this embodiment, the outer shell 1 is provided with a fixed end platform 25 and a sliding platform 22. The sliding platform 22 is connected to a linear drive mechanism, which is fixed to the outer shell 1. The fixed end platform 25 and the sliding platform 22 are respectively provided with open slots. The bottom of the fixed gripper is rotatably installed in the open slot of the fixed end platform 25, and the bottom of the sliding gripper is rotatably installed in the open slot of the sliding platform 22.

[0041] It is easy to understand that the side wall of the open slot 36 is provided with a sliding groove 37. The sliding groove 37 is set along the width direction of the robot arm (which is also the opening direction of the fixed gripper or the sliding gripper). The bottom ends of the fixed gripper 32 and the sliding gripper 33 are respectively provided with connecting parts such as smooth rod bolts. One connecting part is fixed to the open slot, and the other connecting part is set through the sliding groove 37 to limit the linear movement range of the fixed gripper 32 and the sliding gripper 33 through the sliding groove, thereby controlling the state after the fixed gripper and the sliding gripper are closed. After passing through the sliding groove, the connecting part is connected to the crank rocker assembly. The crank rocker assembly is installed on the outer shell 1. Considering the structural space layout, the crank rocker assembly is placed between the fixed gripper 32 and the sliding gripper 33 to ensure the maximum distance between the sliding gripper and the fixed gripper.

[0042] In this embodiment, the linear drive mechanism is a lead screw and nut mechanism. The power source of the lead screw and nut mechanism is located inside the housing. The lead screw and nut mechanism includes a lead screw 17, a lead screw nut 18, and a slide nut 18 connected to a slide table 19. The slide table 19 supports a sliding platform 22. Corrugated protective sleeves are respectively provided on both sides of the lead screw and nut 18. The sliding platform 22 supports the corresponding crank rocker assembly. An open groove 36 is provided on one side of the sliding platform 22, and an end cap 31 is provided on the side of the open groove. The closing status of the fixed gripper 32 and the sliding gripper 33 is limited by the movement distance of the crank rocker assembly along the slide groove 37, so that the fixed gripper 32 clamps the branch while fitting the branch, while the sliding gripper 33 only needs to fit the branch 34.

[0043] It is easy to understand that the two ends of the lead screw 17 are supported by the fixed end 24 and the support end 20 respectively. The fixed end 24 is located inside the outer casing 1, and the support end 20 is located inside the support base. The support base is connected to the outer casing 1 through the bottom support plate, which is placed below the lead screw 17.

[0044] Specifically, the sliding gripper 33 includes two circular clamping plates 7, which are staggered and in contact when closed. The circular clamping plates 7 are arc-shaped. The two circular clamping plates 7 are hinged together near the bottom of the circular clamping plates 7 by a smooth bolt and a nut. A through hole is opened at the bottom of the circular clamping plate 7, and a bearing is installed in the through hole of the circular clamping plate 7. The bolt of one circular clamping plate is fixed to the side wall of the open groove, and the bolt of the other circular clamping plate passes through the through hole of the circular clamping plate 7 and the bearing and enters the slide groove 37 of the side wall of the open groove, connects with the crank rocker assembly, and is equipped with a nut. The slide groove 37 is a straight slide groove, which allows the bottom of the circular clamping plate to move linearly along the slide groove 37. The bottom of the circular clamping plate 7 is installed in the open groove 36 of the sliding platform 22. The slide groove 37 allows the bearing to slide in the slide groove, thereby controlling the opening and closing of the sliding gripper 33. Among them, sliding grooves are respectively provided on the two side walls of the open groove of the sliding platform 22.

[0045] refer to Figure 2 As shown, the sliding platform 22 has threaded holes that are respectively connected to the motor mounting plate 21 and the slide 19. The sliding platform 22 can be connected to the motor mounting plate 21 and the slide 19 by bolts.

[0046] A micro stepper motor 23 is mounted on the motor mounting plate 21, and the two are connected by bolts. A perforated coupling 16 is mounted on the shaft of the micro stepper motor, and a top pin 29 is mounted on the other end of the perforated coupling 16. (Reference) Figure 4 As shown, the end of the top shaft nail 29 is nested with the crank 30. The other end of the crank 30 is connected to one end of the rocker arm 27 by a bolt and nut. The other end of the rocker arm 27 is connected to the rocker arm support ring 26 and the bearing 28 (miniature bearing) by a bolt and nut. The rocker arm support ring 26 is fitted onto the bolt. The rocker arm support ring 26 is set closer to the side wall of the open groove than the rocker arm. The bearing 28 is placed in the slide groove 37 of the sliding platform 22. During the rotation of the crank by the miniature stepper motor 23, because the bolt is placed in the slide groove, the rocker arm 27 drives the circular clamp 7 to move linearly along the slide groove. The circular clamps 7 on both sides move simultaneously, causing the sliding gripper to open or close.

[0047] refer to Figure 2 As shown, the fixed end 24 and the fixed end platform 25 are connected by bolts. The fixed end platform 25 is provided with an open groove. The bottom ends of the double-layer claw piece 10 and the single-layer claw piece 3 in the fixed gripper 32 are connected by bolts and nuts, and then placed together in the open groove 36 of the fixed end platform 25. The bolt at the bottom end of the double-layer claw piece 10 passes through the side walls of the open groove and is fixed. The bolt at the bottom end of the single-layer claw piece passes through the sliding groove 37 on one side wall of the open groove and is connected to the crank rocker assembly. The double-layer gripper plate 10 and the single-layer gripper plate 3 are hinged together at the lower middle section via a smooth bolt and nut. (Refer to...) Figure 3As shown, the single-layer gripper plate 3 is connected to the rocker support ring 26 and one end of the rocker 27 on the basis of the connecting bearing 28. The rocker 27 is connected to the crank by bolts and nuts. The crank 30 is nested with a top shaft pin. The top shaft pin 29 is connected to the micro stepper motor 23 by a plum blossom coupling. The micro stepper motor is mounted on the motor mounting plate 21 by bolts. The motor mounting plate is mounted on the fixed end platform by bolts. It should be noted that the double-layer gripper 10 is provided with a slot in the middle, and when the double-layer gripper and the single-layer gripper are closed, the single-layer gripper can enter the slot of the double-layer gripper. refer to Figure 7 As shown, the middle sections of the double-layer gripper 10 and the single-layer gripper 3 are respectively provided with adhesive grooves 38. The resistance-increasing component is fastened to the lower part of the bend of the double-layer gripper 10. The resistance-increasing component is glued to the adhesive groove 38. The resistance-increasing component of the double-layer gripper 10 is a wide hard corrugated sponge block 11. Another resistance-increasing component, such as a narrow hard corrugated sponge block, is glued to the adhesive groove of the single-layer gripper 3 with strong adhesive. The height of the resistance-increasing component can be greater than the diameter of the branch. The narrow hard corrugated sponge block 2 and the wide hard corrugated sponge block 11 are positioned opposite each other. The surface of the resistance-increasing component forms a wavy protrusion. The wavy protrusion of the resistance-increasing component provides strong assistance for firmly gripping the branch 34. In addition, it is easy to understand that the sliding platform 22 and the fixed end platform 25 are respectively equipped with sliding shield 8 and fixed end shield 9. The sliding shield 8 and the fixed end shield 9 are set to avoid the interference of the external environment on the internal device. The sliding shield 8 and the fixed end shield 9 are both installed on the sliding platform 22 and the fixed end platform 25 respectively by bolts through the holes on both sides. Both the sliding shield 8 and the fixed end shield 9 are provided with wiring holes.

[0048] To prevent external environmental interference with the control performance and service life of the lead screw, the lead screw 17 is covered with a corrugated protective sleeve, specifically a thin lead screw protective sleeve 4 and a thick lead screw protective sleeve 5. Both can protect the lead screw from external dust and other intrusions and can extend and retract as the slide moves. One end of the thin lead screw protective sleeve 4 is attached to the fixed end cover 9, and the other end is attached to the lead screw nut 18. One end of the thick lead screw protective sleeve 5 is attached to the lead screw nut 18, and the other end is attached to the support end cover 6. The thin lead screw protective sleeve 4 and the thick lead screw protective sleeve 5 are made of plastic and can move with the slide 19.

[0049] One end of the lead screw 17 is connected to the medium-sized stepper motor 15, which is located in the housing 1. One end of the lead screw 17 is connected to the shaft of the medium-sized stepper motor through a plum blossom coupling 16. One end of the housing 1 has a boss, which can be a circular boss. A threaded hole is provided at the boss, which can be connected to the robotic arm. A carrier plate 13 is installed on the top of the medium stepper motor 15 at the housing 1. The carrier plate 13 is installed on the housing 1 by bolts. A support end cover 6 is installed on the top of the support end to prevent dust. Additionally, a camera 14 and a laser rangefinder 12 are mounted on the carrier plate 13. The controller is connected to the laser rangefinder 12 and each motor. The camera 14 and the controller are connected to a computing terminal (computer). The controller can be the control system of the robotic arm (PLC controller or other types of controller). The camera 14 is used to perceive visual information of the fruit and branches and sends the collected data to the computing terminal. The image recognition software on the computing terminal identifies the fruit, recognizing it on the tree in real time and assisting in judging the ripeness and position of the fruit. The laser rangefinder 12 is used to measure the distance between the tree-climbing harvesting robot and the branches. Due to its small size, low power consumption, and ease of embedding, the camera is particularly suitable for tree-climbing robots with high requirements for space, weight, and energy consumption. The laser rangefinder is installed next to the camera, mainly for accurate distance measurement and auxiliary positioning, compensating for the shortcomings of the camera in distance perception and improving the accuracy and reliability of the entire system. After the camera and laser rangefinder recognize the information of the fruit target, the controller controls the movement of the robotic arm to bring the robotic arm closer to the fruit target.

[0050] Example 2 This embodiment discloses a working method for a tree-climbing robotic arm used for high-altitude fruit harvesting, including the following: When the tree-climbing robotic arm approaches the target fruit, the camera sends the captured image data to the computing terminal. The computing terminal identifies the fruit and sends the identified fruit's location information to the controller. The controller uses a laser rangefinder to obtain the distance between the robotic arm and the fruit. The controller adjusts the movement of the robotic arm based on the fruit's position information sent by the computing terminal and the distance between the robotic arm and the fruit, so that the sliding gripper moves to the side of the fruit and gets closer to the fruit relative to the fixed gripper. refer to Figure 6 As shown, when the laser rangefinder detects that the distance between the robotic arm and the tree branch is within a suitable range, the controller controls the micro stepper motor to drive the crank to rotate, and drives the fixed gripper and the sliding gripper to move simultaneously through the rocker arm, so that the fixed gripper and the sliding gripper close to fit the tree branch. The fixed gripper clamps the branch with fruit, and the controller controls the movement of the medium-sized stepper motor 15. (See reference) Figure 7 As shown, the sliding gripper moves along the branch towards the fruit, thus detaching the fruit from the branch and dropping it to the ground for harvesting by ground workers. refer to Figure 9As shown, once the fruit has been harvested, the entire tree-climbing robotic arm returns to its original position under the control of the controller and continues to search for the next target.

[0051] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tree-climbing robotic arm for high-altitude fruit harvesting, characterized in that, The device includes an outer shell that can connect to a robotic arm. The outer shell is equipped with a fixed gripper and a movable sliding gripper, allowing the position of the sliding gripper relative to the fixed gripper to be adjustable. Both the fixed and sliding grippers can open and close. When closed, the fixed and sliding grippers can fit onto the branch. When fitting onto the branch, the fixed gripper clamps the branch tightly. The area formed by the sliding gripper after closing is larger than the area formed by the fixed gripper after closing. When fitting onto the branch, the sliding gripper can move along the branch. During the movement, the sliding gripper can touch at least one fruit for harvesting. The housing is provided with a fixed end platform and a sliding platform. The sliding platform is connected to a linear drive mechanism, which is fixed to the housing. The fixed end platform and the sliding platform are respectively provided with open slots. The bottom of the fixed gripper is rotatably installed in the open slot of the fixed end platform, and the bottom of the sliding gripper is rotatably installed in the open slot of the sliding platform. The side wall of the open slot is provided with a sliding groove. The bottom of the fixed gripper and the sliding gripper are respectively provided with connecting members. The connecting members pass through the sliding groove to limit the linear movement of the fixed gripper and the sliding gripper. One connecting member is rotatably installed on the side wall of the open slot, and the other connecting member passes through the sliding groove and is connected to a crank-rocker assembly. The crank-rocker assembly is installed in the housing. The closing state of the fixed gripper and the sliding gripper is limited by the distance the crank-rocker assembly moves along the sliding groove. The fixed gripper includes a double-layer gripper plate and a single-layer gripper plate arranged opposite each other. The double-layer gripper plate has a groove in the middle. When the double-layer gripper plate and the single-layer gripper plate are closed, the single-layer gripper plate can enter the groove of the double-layer gripper plate. Both the double-layer gripper plate and the single-layer gripper plate are bent.

2. The tree-climbing robotic arm for high-altitude fruit harvesting according to claim 1, characterized in that, Both the fixed gripper and the sliding gripper include two opposing grippers. The two grippers of the fixed gripper and the sliding gripper are hinged together, and the bottom end of each gripper is slidable relative to the outer shell. The plane where the fixed clamp is located is parallel to the plane where the sliding clamp is located, and the area of ​​the fixed clamp and the sliding clamp after they are closed is greater than the longitudinal cross-sectional area of ​​the tree branch.

3. A tree-climbing robotic arm for high-altitude fruit harvesting according to claim 1, characterized in that, The crank-rocker assemblies described in both locations are positioned between the fixed gripper and the sliding gripper; The linear drive mechanism is a lead screw and nut mechanism. The power source of the lead screw and nut mechanism is located inside the housing. The lead screw and nut mechanism includes a lead screw, a lead screw nut, and a slide table. The slide table supports the sliding platform. Corrugated protective sleeves are respectively provided on both sides of the lead screw and nut in the circumferential direction.

4. A tree-climbing robotic arm for high-altitude fruit harvesting according to claim 1, characterized in that, The inner surfaces of the double-layer gripper and the single-layer gripper are respectively provided with resistance-enhancing elements to stably grip the tree branch. The resistance-enhancing elements are located in the lower half of the double-layer gripper and the single-layer gripper.

5. A tree-climbing robotic arm for high-altitude fruit harvesting according to claim 1, characterized in that, The sliding gripper includes two opposing circular clamping pieces, which are staggered and in contact when closed, and the circular clamping pieces are arc-shaped.

6. A tree-climbing robotic arm for high-altitude fruit harvesting according to claim 1, characterized in that, The outer shell is provided with a protrusion to connect with the robotic arm. A camera and a laser rangefinder are provided on one side of the outer shell. The laser emitted by the laser rangefinder is parallel to the plane where the fixed gripper is located. The laser rangefinder is placed on one side of the camera. The robotic arm and the laser rangefinder are respectively connected to the controller. The camera and the controller are respectively connected to the computing terminal. Both the crank rocker assembly and the linear drive mechanism are connected to the controller.

7. The working method of a tree-climbing robotic arm for high-altitude fruit harvesting according to claim 6, characterized in that, Includes the following: The camera sends the captured image data to the computing terminal, which identifies the fruit and sends the identified fruit's location information to the controller. The controller then uses a laser rangefinder to obtain the distance between the robotic arm and the fruit. The controller adjusts the movement of the robotic arm based on the fruit's position information and the distance between the robotic arm and the fruit, so that the sliding gripper moves to the side of the fruit and gets closer to the fruit relative to the fixed gripper. When the laser rangefinder detects that the distance between the robotic arm and the tree branch is within a suitable range, the controller controls the crank-slider assembly to move and drive the fixed gripper and sliding gripper to close and engage the tree branch. The controller controls the linear drive mechanism to move the sliding gripper toward the fruit, thereby detaching the fruit from the branch and harvesting it.

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