A contour-profiling harvesting robot system for horizontal trellis fruits and its operation method

Abstract

This invention discloses a contour-profiling harvesting robot system for horizontal trellis fruit and its operating method. The system consists of a floating fruit-grabbing module, a cutting-type picking module, an overhead camera telescopic control module, and a self-propelled chassis module. The system uses a three-dimensional coupled working area of ​​a vision mechanism as the operating width, height, and depth range of the contour-profiling harvesting robot system for horizontal trellis fruit. The camera acquires the three-dimensional spatial coordinates of the fruit's center of mass within the working area in real time, and a main controller extracts the two-dimensional coordinates to achieve rapid horizontal multi-fruit targeting. The robotic arm continuously picks fruit based on the two-dimensional coordinates of the fruit picking points, while the fruit box supports the harvest without damage below the area. The disc cutter end effector accurately senses and adjusts the cutting height using a contouring mesh. Combined with rapid horizontal targeting based on overhead shooting, the disc cutter cuts the horizontal trellis fruit. This invention significantly reduces the harvesting robot's reliance on machine vision.

Description

Technical Field

[0001] The present invention relates to the fields of intelligent agricultural equipment and robots, and in particular to a contour-profiling harvesting robot system for horizontal trellis fruits and an operation method thereof. Background Art

[0002] Currently, horizontal trellis cultivation for high-value crops like grapes, passion fruit, and kiwifruit is rapidly gaining popularity both domestically and internationally. However, the widespread application of harvesting robots for horizontal trellises is hampered by their low harvesting efficiency, leading to an urgent need to improve the harvesting efficiency of horizontal trellis harvesting robots. Conventional harvesting robot solutions rely heavily on high-precision visual-mechanical localization of the fruit stem picking point. Machine vision algorithms must accurately identify the delicate fruit stems amidst the dense, interfering canopy of horizontal trellises. Furthermore, precise positioning of the fruit stems, transfer, boxing, and return of the fruit are also required at the end. These factors contribute to the time-consuming and low harvesting success rates of conventional visual inspection solutions. Visual overhead photography is widely used in agricultural transplanting and consistent harvesting. However, in horizontal trellis cultivation, with its undulating trellis surface, obstructive vines, and varying fruit heights, visual overhead photography alone cannot achieve rapid and precise hand-eye localization of horizontal trellis fruit. Summary of the Invention

[0003] In view of the shortcomings in the prior art, the present invention provides a contour-profiling harvesting robot system for horizontal trellis fruits and an operating method thereof, so as to enable the harvesting robot to quickly and non-destructively harvest the fruits planted on the horizontal trellis with low visual dependence.

[0004] The present invention achieves the above technical objectives through the following technical means.

[0005] A contour-profiling harvesting robot system for horizontal trellis fruits comprises a floating fruit receiving module, a cutting picking module, an upward-facing camera telescopic control module, and a chassis self-propelled module. The floating fruit receiving module and the cutting picking module are fixedly mounted on the front and middle sections of the chassis self-propelled module, respectively, along the longitudinal centerline of the chassis self-propelled module, and are both located above the chassis self-propelled module. The upward-facing camera telescopic control module is fixedly mounted below the front end of the chassis self-propelled module, along the longitudinal centerline of the chassis self-propelled module.

[0006] The floating fruit receiving module includes a fruit box, a lifting platform and a fruit box quick-change positioning mechanism. The fruit box is detachably mounted on the upper portion of the lifting platform through the fruit box quick-change positioning mechanism, and the lifting platform is mounted on the chassis self-propelled module.

[0007] The cutting picking module includes a robotic arm and a disc knife end effector. The disc knife end effector is fixed to the end wrist of the robotic arm, and its working posture is horizontal and its movement direction is parallel to the longitudinal center line of the chassis self-propelled module. The base at the bottom of the robotic arm is installed above the base platform, and the base platform is installed on the chassis self-propelled module.

[0008] The upward-shooting camera telescopic control module includes an upward-shooting depth camera and a floating camera bracket. The floating camera bracket includes a camera fixing rod, an electric push rod and a U-shaped base. The base of the electric push rod is fixed to the front end of the chassis self-propelled module through the U-shaped base. The camera fixing rod and the end of the telescopic shaft of the electric push rod are fixedly connected. The upward-shooting depth camera is horizontally fixed on the top of the camera fixing rod, and the shooting direction of the upward-shooting depth camera is vertically upward along the longitudinal center line of the chassis self-propelled module.

[0009] In the above technical solution, the disc knife end effector includes a disc knife, a drive motor, a connecting rod, a curved top plate, an elastic connecting rod and a film pressure sensor. The elastic connecting rod is retractable in the vertical direction and cannot be bent. The curved top plate is fixedly installed on the top of the elastic connecting rod. The curved top plate is in contact with the mesh surface of the horizontal scaffolding. A film pressure sensor is fixedly installed at the bottom of the elastic connecting rod. The film pressure sensor is installed in the middle section of the connecting rod. One end of the connecting rod is fixed to the end wrist of the robotic arm, and the drive motor is installed at the end. The disc knife is installed at the other end of the connecting rod through an axis. The axis and the output shaft of the drive motor are transmitted through a gear belt.

[0010] In the above technical solution, the fruit box quick-change positioning mechanism includes a fixed clip, a horizontal rotating shaft, a swing motor and a movable clip. The fixed clip is fixed on one side of the lifting platform and is used to clamp the groove on the edge of one side of the fruit box. The swing motor is installed on the lifting platform, and the swing motor output shaft is connected to the horizontal rotating shaft. The movable clip is fixedly connected to the horizontal rotating shaft.

[0011] In the above technical solution, the movements of the chassis self-propelled module, robotic arm, lifting platform, swing motor, drive motor and electric push rod are all controlled by the main controller, and the main controller unidirectionally receives signals from the overhead depth camera and the film pressure sensor.

[0012] An operating method of a contour-harvesting robot system for horizontal trellis fruits:

[0013] The self-propelled chassis module is longitudinally aligned with the row of fruit trees and is ready for harvesting. The lifting platform raises the bottom of the fruit box to a height of h1. The electric push rod extends forward a distance d1 to push the overhead depth camera to the overhead shooting position. The robotic arm is raised to make the curved top plate contact the horizontal trellis mesh surface until the deformation of the elastic connecting rod is L1. At this time, the initial height of the disc knife from the horizontal trellis mesh surface is H1, and then waits for the picking action instruction; where h1 = 1500mm, d1 = 500mm, and L1 = 15mm;

[0014] During the harvesting process, the upward-shooting depth camera obtains the two-dimensional plane coordinates of the mass center of all target fruits in the vision-mechanism three-dimensional coupling working area, performs picking task planning, and adjusts the fruit receiving height of the fruit box according to the average height value of the mass center of each target fruit;

[0015] During the picking process of the robotic arm, the cutting height of the disc knife end effector is adjusted according to the height change of the horizontal scaffolding mesh surface, so that the height between the disc knife end effector and the horizontal scaffolding mesh surface is maintained at H1, so that the film pressure sensor feeds back the extrusion force F to the main controller. d Satisfy 0.75F1≤F d ≤1.25F1; the drive motor works to drive the disc knife to cut the target fruit, achieving rapid cutting of horizontal trellis fruit; where F1 is the extrusion force corresponding to the deformation variable L1;

[0016] At this point, after completing the harvesting of all fruits in the vision-mechanism three-dimensional coupling working area, the chassis self-propelled module moves forward in a straight line along the line of fruit trees for a distance D to reach the next harvesting area to continue harvesting, and repeats this cycle to complete the continuous cutting and harvesting operation of the trellis fruits.

[0017] Furthermore, the vision-mechanism three-dimensional coupling working area is the maximum inscribed rectangular parallelepiped area formed by the common three-dimensional area jointly determined by the manipulator workspace, the field of view space of the overhead depth camera, and the fruit box body space; the range parameters of the manipulator and the range parameters of the overhead depth camera respectively satisfy:

[0018]

[0019] Where: W b is the working width of the robot's working space, W g is the horizontal width of the fruit box body, D b is the operating depth range of the robotic arm, D bmax is the maximum operating depth of the robotic arm, D bmin is the minimum operating depth of the robot arm, θ v is the field of view of the upward-shooting depth camera constrained by the fruit box in the vertical direction, θ w H is the maximum horizontal field of view of the upward-shooting depth camera, s L is the maximum vertical distance between the upward-shooting depth camera and the upper edge of the fruit box. c H is the horizontal distance between the upward-shooting depth camera and the vertical center line of the fruit box, c H is the height of the depth camera installed above the ground. wmin L is the minimum height of the horizontal scaffolding surface from the ground. b Indicates the horizontal distance between the base platform and the lifting platform along the longitudinal centerline of the chassis self-propelled module, H b Indicates the operating height range of the robot arm.

[0020] Furthermore, the fruit receiving height of the fruit box is adjusted according to the average value of the height of the center of mass of each target fruit, specifically:

[0021] H z =z m -400

[0022] Among them, z m It is the average height of the mass center of all target fruits in the vision-mechanism three-dimensional coupling working area, and its unit is mm. z It is the height of the bottom of the fruit box from the ground, and its unit is mm.

[0023] Furthermore, if the extrusion force F d >1.25F1, it is considered that the disc cutter end effector is too close to the horizontal scaffolding mesh surface, and the main controller controls the robot arm to lower the operating height, so that the extrusion force F fed back by the film pressure sensor d Approximate extrusion force F1, that is, 0.75F1≤F d ≤1.25F1.

[0024] Furthermore, if the extrusion force F d <0.75F1, it is considered that the disc cutter end effector is too far away from the horizontal scaffolding mesh surface, and the main controller controls the robot arm to raise the working height so that the extrusion force F fed back by the film pressure sensor d Approximate extrusion force F1, that is, 0.75F1≤F d ≤1.25F1.

[0025] The beneficial effects of the present invention are:

[0026] (1) The present invention uses the vision-mechanism three-dimensional coupling working area as the operating width, operating height, and operating depth range of the contour-harvesting robot system for horizontal trellis fruits, which greatly improves the phenomenon of branch and leaf occlusion and interference at the horizontal trellis canopy. It can quickly calculate the two-dimensional plane picking point coordinates of limited fruits within the vision-mechanism three-dimensional coupling working area, and realize rapid two-dimensional horizontal plane targeting of target fruits.

[0027] (2) The present invention establishes a high-profile profiling strategy between the disc knife end effector and the horizontal trellis mesh. The arc-shaped top plate above the disc knife end effector can accurately sense the vertical distance between the disc knife and the top horizontal trellis mesh through a piezoelectric sensor, and controls the robotic arm to profile and adjust the cutting height of the disc knife to accurately cut the fruit stem close to the horizontal trellis mesh. Combined with the rapid targeting of the visual two-dimensional horizontal plane, the disc knife can achieve continuous cutting and harvesting of horizontal trellis fruits, and greatly reduce the robot's dependence on visual positioning accuracy. The structure and method are simple, reliable, and highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1This is a schematic diagram of the scene of horizontal scaffolding inter-row harvesting according to the present invention;

[0029] Figure 2 Schematic diagram of the contour-profiling harvesting robot for horizontal trellis fruits according to the present invention;

[0030] FIG3( a ) is a schematic diagram of the telescopic control module of the upward-shooting camera of the present invention in a retracted state;

[0031] FIG3( b ) is a schematic diagram of the telescopic control module of the upward-shooting camera of the present invention in an extended state;

[0032] Figure 4 This is a schematic diagram of the quick-change positioning mechanism for the fruit box;

[0033] FIG5( a ) is a schematic diagram of the disc cutter end effector of the present invention;

[0034] FIG5( b ) is a cross-sectional view of the disc cutter end effector of the present invention;

[0035] Figure 6 Schematic diagram of communication between the main controller and other components of the present invention;

[0036] Figure 7 A schematic diagram of the construction of a three-dimensional coupled working area of ​​vision and mechanism for limited bunch grape harvesting with multi-parameter constraints according to the present invention;

[0037] Figure 8 Schematic diagram of the net height profiling control method of the present invention;

[0038] In the figure: 1- floating fruit receiving module, 2- cutting picking module, 3- upward camera telescopic control module, 4- chassis self-propelled module, 5- robotic arm, 6- disc knife end effector, 7- upward depth camera, 8- base platform, 9- fruit box, 10- lifting platform, 11- disc knife, 12- fixed buckle, 13- horizontal rotation axis, 14- swing motor, 15- movable buckle, 16- vision-mechanism three-dimensional coupling working area, 17- driving motor, 18- camera fixing connecting rod, 19- electric push rod, 20- U-shaped base, 21- main controller, 22- curved top plate, 23- elastic connecting rod, 24- film pressure sensor, 25- horizontal trellis mesh, 26- connecting rod. DETAILED DESCRIPTION

[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the protection scope of the present invention is not limited thereto.

[0040] like Figure 1As shown, the present invention provides a contour-profiling robot harvesting system for horizontal trellis fruit, comprising a floating fruit receiving module 1, a cutting-type picking module 2, an overhead camera telescopic control module 3, and a self-propelled chassis module 4. The floating fruit receiving module 1 and the cutting-type picking module 2 are fixedly mounted to the front and middle sections of the self-propelled chassis module 4, respectively, along the longitudinal centerline of the self-propelled chassis module 4, and are both located above the self-propelled chassis module 4. The overhead camera telescopic control module 3 is fixedly mounted below the front end of the self-propelled chassis module 4, along the longitudinal centerline of the self-propelled chassis module 4.

[0041] like Figure 2 As shown, the floating fruit receiving module 1 includes a fruit box 9, a lifting platform 10 and a fruit box quick-change positioning mechanism. The fruit box 9 can be detachably installed on the upper part of the lifting platform 10 through the fruit box quick-change positioning mechanism, and the lifting platform 10 is installed on the chassis self-propelled module 4.

[0042] like Figure 4 As shown, the fruit box quick-change positioning mechanism includes a fixed buckle 12, a horizontal rotating shaft 13, a swinging motor 14 and a movable buckle 15. The fixed buckle 12 is fixed to one side of the lifting platform 10 and clamps the groove on one edge of the fruit box 9. The swinging motor 14 is installed on the lifting platform 10, and the output shaft of the swinging motor 14 is connected to the horizontal rotating shaft 13. The movable buckle 15 and the horizontal rotating shaft 13 are fixed. After the fruit box 9 is placed in place, the swinging motor 14 controls the movable buckle 15 to clamp the groove on the other edge of the fruit box 9, thereby fixing the fruit box 9 above the lifting platform 10; the swinging motor 14 controls the movable buckle 15 to rotate in the opposite direction and disengage from the groove on the edge of the fruit box 9. The fruit box 9 will lose the locking constraint on this side, and the fruit box 9 can be smoothly unloaded along this side edge.

[0043] like Figure 2 As shown, the cutting and picking module 2 includes a robotic arm 5 and a disc blade end effector 6. The disc blade end effector 6 is fixed to the wrist of the robotic arm 5, with its working posture horizontal and its movement direction parallel to the longitudinal centerline of the chassis self-propelled module 4. The base of the robotic arm 5 is mounted above a base platform 8, which is mounted on the chassis self-propelled module 4.

[0044] As shown in Figures 5(a) and (b), the disc knife end effector 6 includes a disc knife 11, a drive motor 17, a connecting rod 26, a curved top plate 22, an elastic connecting rod 23 and a film pressure sensor 24. The elastic connecting rod 23 is retractable in the vertical direction, cannot be bent, and has a curved top plate 22 fixedly installed on the top. The curved top plate 22 contacts the mesh surface 25 of the horizontal scaffolding and is subjected to a vertical downward extrusion force, thereby compressing the length of the elastic connecting rod 23. The extrusion force exerted on the elastic connecting rod 23 is further transmitted to the film pressure sensor 24 fixedly installed at the bottom of the elastic connecting rod 23; the film pressure sensor 24 is installed in the middle section of the connecting rod 26, one end of the connecting rod 26 is fixed to the end wrist of the robot arm 5, and the drive motor 17 is installed at the end, and the disc knife 11 is installed on the other end of the connecting rod 26 through an axis rotation, and the axis and the output shaft of the drive motor 17 are driven by a gear belt. In addition, the axis for installing the disc knife 11 is also fixed to the connecting rod 26 through a bending plate.

[0045] As shown in Figures 3(a) and (b), the upward camera telescopic control module 3 includes an upward depth camera 7 and a floating camera bracket. The floating camera bracket includes a camera fixing link 18, an electric push rod 19 and a U-shaped base 20. The base of the electric push rod 19 is fixed to the front end of the chassis self-propelled module 4 through two U-shaped bases 20. The camera fixing link 18 and the end of the telescopic axis of the electric push rod 19 are fixedly connected. The upward depth camera 7 is horizontally fixed to the top of the camera fixing link 18, and the shooting direction of the upward depth camera 7 is vertically upward along the longitudinal center line of the chassis self-propelled module 4; before the robot harvesting operation starts, the electric push rod 19 extends to control the upward depth camera 7 to reach the shooting position along the longitudinal center line of the chassis self-propelled module 4. After the robot harvesting operation is completed, the electric push rod 19 contracts to retract the upward depth camera 7.

[0046] like Figure 6 As shown, the main controller 21 transmits signals to the chassis self-propelled module 4, the robotic arm 5, the lifting platform 10, the swing motor 14, the drive motor 17 and the electric push rod 19 in a unidirectional manner; the actions of the chassis self-propelled module 4, the robotic arm 5, the lifting platform 10, the swing motor 14, the drive motor 17 and the electric push rod 19 are all controlled by the main controller 21; the main controller 21 receives signals from the overhead depth camera 7 and the film pressure sensor 24 in a unidirectional manner.

[0047] The operating method of the horizontal trellis fruit profiling harvesting robot system of the present invention includes a vision-mechanism three-dimensional coupling working area control sub-method, a mesh height profiling control sub-method and a harvesting operation flow of the horizontal trellis fruit profiling harvesting robot system.

[0048] The vision-mechanism three-dimensional coupling working area control sub-method includes the vision-mechanism three-dimensional coupling working area calculation model and the fruit box lifting and lowering control algorithm.

[0049] like Figure 7 As shown, the vision-mechanism 3D coupling work area calculation model calculates the vision-mechanism 3D coupling work area 16 based on the range parameters and relative installation positions of the manipulator 5, the overhead depth camera 7, and the fruit box 9. This is the workspace range that the contour-profiling harvesting robot for horizontal trellis fruits can cover, which determines its operating width range B, operating height range H, and operating depth range D. The vision-mechanism 3D coupling work area 16 is the maximum inscribed rectangular parallelepiped area formed by the common 3D area jointly determined by the manipulator workspace Θ, the depth camera's field of view space θ, and the fruit box body space γ. The range parameters Ψ of the vision-mechanism 3D coupling work area 16, the range parameters Θ of the manipulator 5, and the range parameters θ of the overhead depth camera 7 satisfy:

[0050] Ψ=[B,H,D]

[0051]

[0052] Where: Ψ represents the vision-mechanism three-dimensional coupling working area, B, H, and D represent the working width range, working height range, and working depth range of the horizontal trellis fruit copying harvesting robot, respectively. b is the working width of the working space Θ of the robot arm 5, W g is the horizontal width of the fruit box 9, D b is the operating depth range of the robot arm 5, D bmax is the maximum operating depth of the robot arm 5, D bmin is the minimum operating depth of the robot arm 5, θ v is the field of view of the upward-shooting depth camera 7 constrained by the fruit box 9 in the vertical direction, θ w H is the maximum horizontal field of view of the upward-shooting depth camera 7. s is the maximum vertical distance between the upward shooting depth camera 7 and the upper edge of the fruit box 9, L c H is the horizontal distance between the vertical center line of the upward shooting depth camera 7 and the fruit box 9, c H is the height of the depth camera 7 installed above the ground. wmin L is the minimum height of the horizontal scaffolding surface 25 from the ground, b H represents the horizontal distance between the base platform 8 and the lifting platform 10 along the longitudinal center line of the chassis self-propelled module 4. b Indicates the operating height range of the robot arm.

[0053] In this embodiment, the lateral width W of the fruit box 9 is g Take 1200mm, the field of view angle θ of the upward shooting depth camera 7 is constrained by the fruit box 9 in the vertical direction v Take 34.5°, the maximum vertical distance H between the upward shooting depth camera 7 and the upper edge of the fruit box 9 sTake 1000mm, the horizontal distance L between the vertical center line of the upward shooting depth camera 7 and the fruit box 9 c Take 850mm as the height H of the installation of the depth camera 7 from the ground c Take 400mm.

[0054] During the harvesting process, the upward shooting depth camera 7 takes fixed frames to continuously shoot and detect the vision-mechanism three-dimensional coupling working area 16, and obtains the three-dimensional spatial coordinates S of the mass center of all fruits in the vision-mechanism three-dimensional coupling working area 16 in real time. zi (x zi ,y zi , z zi ), calculate the three-dimensional space coordinates S of the fruit center of mass zi The method is prior art and will not be elaborated here.

[0055] The main controller 21 calculates the three-dimensional space coordinates S of the fruit mass center according to the zi (x zi ,y zi , z zi ) extract its horizontal two-dimensional plane coordinates (x zi ,y zi ), complete the multi-target rapid targeting on the horizontal plane, and further according to the two-dimensional horizontal coordinates (x zi ,y zi ) to perform picking task planning (existing technology) and extract the height value z of the fruit center of mass zi , determine the operating height of the lifting platform 10 to adjust the lifting of the fruit box to achieve lossless fruit harvesting.

[0056] The fruit box lifting control algorithm is as follows: the main controller 21 calculates the height value (z z1 , z z2 ,…z zi ,…z zn ) average value to automatically adjust the working height of the lifting platform 10, the lifting platform 10 controls the height of the fruit box 9 to support the fruit without damage; adjust the working height of the lifting platform 10 so that the height H of the bottom of the fruit box 9 from the ground z The relationship between the average value of the height of the target fruit mass center satisfies:

[0057]

[0058] H z =z m -400

[0059] Where: z zi ∈[z zmin ,z zmax ],z zminIndicates the minimum value of the target fruit's centroid height, z max Indicates the maximum value of the target fruit's centroid height, z m Represents the average value of the target fruit's centroid height.

[0060] The specific workflow of the mesh height profiling control sub-method is as follows: Figure 8 As shown, the main controller 21 controls the robot arm 5 to approach the two-dimensional plane coordinate (x zi ,y zi ), during the movement of the robotic arm 5, the arc-shaped top plate 22 above the disc cutter end effector 6 contacts the horizontal scaffolding mesh 25 and presses the elastic connecting rod 23 downwards, and the film pressure sensor 24 measures the squeezing force F on the elastic connecting rod 23. d Feedback to the main controller 21.

[0061] The mesh height profiling control sub-method includes the mesh surface profiling perception strategy and the robot arm operation height control strategy.

[0062] Net surface profiling perception strategy: During the harvesting operation of the robot arm 5 in the vision-mechanism three-dimensional coupling working area 16, the main controller 21 receives the squeezing force F fed back by the film pressure sensor 24. d , and according to the extrusion force F d Calculate the deformation L of the elastic link 23 d At this time, the vertical height between the disc cutter 11 and the horizontal scaffolding mesh surface 25 is:

[0063] H d =L t -L d

[0064] Among them, H d Indicates the vertical height between the disc cutter 11 and the horizontal scaffolding mesh 25, L t It represents the vertical height between the upper surface of the arc top plate 22 and the disc cutter 11 when the elastic connecting rod 23 is not squeezed, L d It represents the deformation of the elastic connecting rod 23 caused by the compression of the horizontal scaffolding mesh surface 25.

[0065] The main controller 21 is based on the extrusion force F d The change of the working height of the robot arm 5 is adjusted, and the cutting height of the disc knife end effector 6 is changed, so that the extrusion force fed back to the main controller 21 by the film pressure sensor 24 is always close to F1 (0.75F1≤F d ≤1.25F), thereby constraining the height value between the disc knife end effector 6 and the horizontal trellis mesh surface 25 to be fixed, preventing the disc knife from cutting the horizontal trellis mesh surface 25 or the fruit body.

[0066] Manipulator operation height control strategy: When the main controller 21 determines the extrusion force F fed back by the film pressure sensor 24 d >1.25F1, it is considered that the disc cutter end effector 6 is too close to the horizontal scaffolding mesh surface 25, and the main controller 21 controls the robot arm 5 to appropriately lower the operating height so that the extrusion force F fed back by the film pressure sensor 24 d Actively approach the initial squeezing force F1; when the main controller 21 determines the squeezing force F fed back by the film pressure sensor 24 d <0.75F1, it is considered that the disc cutter end effector 6 is too far away from the horizontal scaffolding mesh surface 25, and the main controller 21 controls the robot arm 5 to properly raise the working height so that the extrusion force F fed back by the film pressure sensor 24 d Actively approaching the initial squeezing force F1. Through the robot arm operation height control strategy, the disc knife avoids damaging the horizontal trellis mesh surface 25 or the fruit body, and realizes efficient and non-destructive harvesting at the height of the horizontal trellis mesh surface 25 by the disc knife end effector 6.

[0067] In this embodiment, the initial extrusion force F1 =40 g·m / s 2 , and the deformation amount L1 of the elastic connecting rod 23 corresponding to F1 =15 mm.

[0068] The operating process of the horizontal trellis fruit contour harvesting robot system is as follows:

[0069] The chassis self-propelled module 4 is longitudinally aligned with the fruit tree row and is ready for harvesting. The lifting platform 10 raises the bottom of the fruit box 9 to a height of h1. The electric push rod 19 extends forward a distance d1 to push the overhead depth camera 7 to the overhead shooting position. The robotic arm 5 is raised to a height so that the arc-shaped top plate 22 above the disc knife end effector 6 contacts the horizontal trellis mesh 25. The deformation of the elastic connecting rod 23 is L1. At this time, the initial height of the disc knife 11 from the horizontal trellis mesh 25 is H1, and then the picking action instruction is waited for. In this embodiment, h1 = 1500mm and d1 = 500mm.

[0070] During the harvesting process, the upward shooting depth camera 7 takes fixed frames to continuously detect the vision-mechanism three-dimensional coupling working area 16, and obtains the two-dimensional plane coordinates (x zi ,y zi ), perform picking task planning, and extract the height value z of the mass center of each target fruit zi , according to the average value of the height of each target fruit center of mass, the fruit height of the fruit box 9 is adjusted to achieve lossless fruit harvesting;

[0071] During the picking movement of the robotic arm 5, the cutting height of the disc knife end effector 6 is floatingly adjusted according to the height change of the horizontal scaffolding 25 based on the mesh height profiling control sub-method, so that the cutting height of the disc knife end effector 6 and the height of the horizontal scaffolding 25 remain relatively fixed, so that the extrusion force fed back to the main controller 21 by the film pressure sensor 24 always approaches F1, the drive motor 17 works, and the disc knife 11 is driven to cut the target fruit, thereby achieving rapid cutting of the horizontal scaffolding fruit;

[0072] At this point, after completing the harvesting of all grapes in the vision-mechanism three-dimensional coupling working area 16, the chassis self-propelled module 4 moves forward in a straight line along the fruit tree line for a distance D to reach the next harvesting area to continue harvesting, and repeats this cycle to complete the continuous cutting and harvesting operation of the trellis fruit.

[0073] The embodiments described are preferred implementations of the present invention, but the present invention is not limited to the above implementations. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention are within the scope of protection of the present invention.

Claims

1. A contour-profiling harvesting robot system for horizontal trellis fruits, characterized in that: The invention comprises a floating fruit receiving module (1), a cutting-type picking module (2), an upward-shooting camera telescopic control module (3) and a chassis self-propelled module (4), wherein the floating fruit receiving module (1) and the cutting-type picking module (2) are fixedly installed at the front end and the middle section of the chassis self-propelled module (4) along the longitudinal center line of the chassis self-propelled module (4) in sequence, and are both located above the chassis self-propelled module (4); the upward-shooting camera telescopic control module (3) is fixedly installed at the lower front end of the chassis self-propelled module (4) along the longitudinal center line of the chassis self-propelled module (4); The floating fruit receiving module (1) comprises a fruit box (9), a lifting platform (10) and a fruit box quick-change positioning mechanism, wherein the fruit box (9) is detachably mounted on the upper portion of the lifting platform (10) via the fruit box quick-change positioning mechanism, and the lifting platform (10) is mounted on a chassis self-propelled module (4); The cutting-type picking module (2) comprises a mechanical arm (5) and a disc knife end effector (6), wherein the disc knife end effector (6) is fixed to the end wrist of the mechanical arm (5), its working posture is horizontal and its movement direction is parallel to the longitudinal center line of the chassis self-propelled module (4), and the base at the bottom of the mechanical arm (5) is installed above the base platform (8), and the base platform (8) is installed on the chassis self-propelled module (4); The upward-shooting camera telescopic control module (3) includes an upward-shooting depth camera (7) and a floating camera bracket, the floating camera bracket includes a camera fixing connecting rod (18), an electric push rod (19) and a U-shaped base (20), the base of the electric push rod (19) is fixed to the front end of the chassis self-propelled module (4) through the U-shaped base (20), the camera fixing connecting rod (18) and the telescopic shaft end of the electric push rod (19) are fixedly connected, the upward-shooting depth camera (7) is horizontally fixed to the top of the camera fixing connecting rod (18), and the shooting direction of the upward-shooting depth camera (7) is vertically upward along the longitudinal center line of the chassis self-propelled module (4); The disc knife end effector (6) comprises a disc knife (11), a driving motor (17), a connecting rod (26), an arc top plate (22), an elastic connecting rod (23) and a film pressure sensor (24); the elastic connecting rod (23) is vertically retractable and non-bendable, and the arc top plate (22) is fixedly installed on the top of the elastic connecting rod (23); the arc top plate (22) contacts the mesh surface (25) of the horizontal scaffold; the film pressure sensor (24) is fixedly installed on the bottom of the elastic connecting rod (23); the film pressure sensor (24) is installed in the middle section of the connecting rod (26); one end of the connecting rod (26) is fixed to the end wrist of the robot arm (5), and the driving motor (17) is installed on the end; the disc knife (11) is rotatably installed on the other end of the connecting rod (26) through an axis; the axis and the output shaft of the driving motor (17) are driven by a gear belt; During the harvesting operation of the mechanical arm (5) in the vision-mechanism three-dimensional coupling working area (16), the main controller (21) receives the squeezing force F fed back by the film pressure sensor (24). d , and according to the extrusion force F d Calculate the deformation L of the elastic link (23) d .

2. The horizontal trellis fruit contour harvesting robot system according to claim 1, characterized in that: The fruit box quick-change positioning mechanism comprises a fixed buckle (12), a horizontal rotating shaft (13), a swing motor (14) and a movable buckle (15). The fixed buckle (12) is fixed to one side of the lifting platform (10) and is used to clamp the groove on the edge of one side of the fruit box (9). The swing motor (14) is installed on the lifting platform (10), and the output shaft of the swing motor (14) is connected to the horizontal rotating shaft (13). The movable buckle (15) is fixedly connected to the horizontal rotating shaft (13).

3. The horizontal trellis fruit contour harvesting robot system according to claim 2, characterized in that: The movements of the chassis self-propelled module (4), the mechanical arm (5), the lifting platform (10), the swing motor (14), the drive motor (17) and the electric push rod (19) are all controlled by a main controller (21), and the main controller (21) unidirectionally receives signals from the overhead depth camera (7) and the film pressure sensor (24).

4. A method for implementing the contour-profiling harvesting robot system for horizontal trellis fruits according to any one of claims 1 to 3, characterized in that: The chassis self-propelled module (4) is longitudinally aligned with the fruit tree line to prepare for walking and harvesting, the lifting platform (10) raises the bottom of the fruit box (9) to a height of h1, the electric push rod (19) extends forward a distance d1 to push the overhead depth camera (7) to an overhead shooting position, and the mechanical arm (5) is raised to make the arc top plate (22) contact the horizontal scaffolding mesh surface (25) until the deformation of the elastic connecting rod (23) is L1. At this time, the initial height value of the disc knife (11) from the horizontal scaffolding mesh surface (25) is H1, and then waits for the picking action instruction; Where h1 = 1500 mm, d1 = 500 mm, L1 = 15 mm; During the harvesting process, the upward-shooting depth camera (7) obtains the two-dimensional plane coordinates of the mass centers of all target fruits in the vision-mechanism three-dimensional coupling working area (16), performs picking task planning, and adjusts the fruit receiving height of the fruit box (9) according to the average value of the height values ​​of the mass centers of each target fruit; During the picking movement of the robotic arm (5), the cutting height of the disc knife end effector (6) is adjusted according to the height change of the horizontal scaffolding mesh surface (25), so that the height between the disc knife end effector (6) and the horizontal scaffolding mesh surface (25) is maintained at H1, so that the extrusion force F fed back to the main controller (21) by the film pressure sensor (24) is d Satisfy 0.75F1≤F d ≤1.25F1; the drive motor (17) works to drive the disc knife (11) to cut the target fruit, thereby achieving rapid cutting of the horizontal trellis fruit; wherein F1 is the extrusion force corresponding to the deformation variable L1; At this point, after completing the harvesting of all fruits in the vision-mechanism three-dimensional coupling working area (16), the chassis self-propelled module (4) moves forward in a straight line along the line of fruit trees for a distance D to reach the next harvesting area to continue harvesting, and this cycle is repeated to complete the continuous cutting and harvesting operation of the trellis fruits.

5. The operation method according to claim 4, characterized in that: The vision-mechanism three-dimensional coupling working area (16) is the largest inscribed cuboid area formed by the common three-dimensional area determined by the working space of the manipulator, the field of view space of the upward-shooting depth camera and the fruit box body space; the range parameters of the manipulator and the range parameters of the upward-shooting depth camera respectively satisfy: Where: W b is the working width of the robot's working space, W g is the horizontal width of the fruit box body, D b is the operating depth range of the robotic arm, D bmax is the maximum operating depth of the robotic arm, D bmin is the minimum operating depth of the robot arm, θ v is the field of view of the upward-shooting depth camera constrained by the fruit box in the vertical direction, θ w H is the maximum horizontal field of view of the upward-shooting depth camera, s L is the maximum vertical distance between the upward-shooting depth camera and the upper edge of the fruit box. c H is the horizontal distance between the upward-shooting depth camera and the vertical center line of the fruit box, c H is the height of the depth camera installed above the ground. wmin L is the minimum height of the horizontal scaffolding surface from the ground. b Indicates the horizontal distance between the base platform and the lifting platform along the longitudinal centerline of the chassis self-propelled module, H b It represents the operating height range of the robotic arm, and D represents the operating depth range of the contour harvesting robot for horizontal trellis fruits.

6. The operation method according to claim 4, characterized in that: The fruit receiving height of the fruit box (9) is adjusted according to the average value of the height of the mass center of each target fruit, specifically: H z =z m -400 Among them, z m H is the average height of all target fruit mass centers in the vision-mechanism three-dimensional coupling working area (16), and its unit is mm. z It is the height from the ground of the bottom of the fruit box (9), and its unit is mm.

7. The operation method according to claim 4, characterized in that: If the extrusion pressure F d >1.25F1, it is considered that the disc knife end effector (6) is too close to the horizontal scaffolding mesh surface (25), and the main controller (21) controls the robot arm (5) to lower the working height so that the extrusion force F fed back by the film pressure sensor (24) d Approximate extrusion force F1, that is, 0.75F1≤F d ≤1.25F1.

8. The operation method according to claim 4, characterized in that: If the extrusion pressure F d <0.75F1, it is considered that the disc knife end effector (6) is too far away from the horizontal scaffolding mesh surface (25), and the main controller (21) controls the robot arm (5) to raise the working height so that the extrusion force F fed back by the film pressure sensor (24) d Approximate extrusion force F1, that is, 0.75F1≤F d ≤1.25F1.

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