Picking robot and picking method thereof

Abstract

The invention relates to the technical field of intelligent robots, and discloses a picking robot and a picking method thereof. A collection box; the picking mechanism comprises a mechanical arm; a grasping part; an industrial camera; and a separating part. When fruits and vegetables are picked, the positions of the fruits and vegetables and fruit stems are positioned through machine vision, a constant-pressure loop is adopted for driving the grabbing paw, the clamping force of the grabbing paw is kept constant so as to achieve flexible grabbing, damage caused by excessive extrusion is avoided, and the damage rate of the fruits and vegetables is reduced; and the fruit stems are cut off by laser, so that the notches of the fruit stems are flat, the invasion risk of pathogenic microorganisms is reduced, and the infection rate of the notches is reduced, thereby reducing the use of chemical preservatives and prolonging the fresh-keeping period.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent robots, and in particular to a picking robot and a picking method thereof. Background Art

[0002] With the continuous development of industrialization and urbanization, the number of people engaged in direct agricultural labor has begun to decrease. In addition, the aging of the population has become an inevitable fact. All of this has led to a continuous increase in agricultural labor costs. Therefore, agricultural mechanization has gradually developed towards intelligence in the post-industrial period. With the continuous development of industrialization and urbanization, the number of people engaged in direct agricultural labor has begun to decrease. In addition, the aging of the population has become an inevitable fact. All of this has led to a continuous increase in agricultural labor costs. Therefore, agricultural mechanization has gradually developed towards intelligence in the post-industrial period.

[0003] At present, the manipulators of agricultural harvesting robots are mostly made of rigid materials and have a preset fixed force design, lacking the ability to dynamically adjust the surface pressure of fruits and vegetables. If traditional manipulators use a single clamping force, it is easy to cause skin damage or internal bruises due to excessive force. Data show that the damage rate of fruits and vegetables in traditional mechanized picking in my country is as high as 25%-30%. In addition, traditional driving methods, such as motor drive and mechanical drive, also make it difficult to achieve precise control of the gripping force of the manipulator, and it is impossible to control the gripping force of the manipulator within the tolerable range of the fruit and vegetable skin.

[0004] In addition, the current agricultural harvesting robots mostly use scissors and rotating blades for cutting, but this cutting method can easily cause water evaporation from the incision and spread plant diseases.

[0005] Therefore, in response to the above problems, there is an urgent need to design a new picking robot that can effectively protect the fruits and vegetables themselves, realize flexible picking, and prevent the fruit stalk cuts from being invaded by pathogenic microorganisms, thereby extending the shelf life of fruits and vegetables and reducing the damage rate of fruits and vegetables while realizing automated picking. Summary of the invention

[0006] The present invention provides a picking robot and a picking method thereof, which effectively protect the fruit and vegetable body, achieve the purpose of flexible picking, and reduce the damage rate of the fruit and vegetable.

[0007] In a first aspect, an embodiment of the present invention provides a picking robot, comprising:

[0008] A walking mechanism;

[0009] a collection box;

[0010] A picking mechanism, the picking mechanism comprising:

[0011] A robotic arm having multiple degrees of freedom;

[0012] A gripping portion, comprising a gripping claw and a driving motor, wherein the driving motor is used to drive the gripping claw to open and close;

[0013] A visual device for collecting images of fruits and vegetables, processing them in real time, and obtaining position information and stem diameter information of fruits and vegetables;

[0014] A separation part is used for cutting the fruit stem.

[0015] Furthermore, the walking mechanism comprises:

[0016] A vehicle body; wherein the picking mechanism and the collecting box are both arranged on the vehicle body.

[0017] Furthermore, it also includes a control mechanism, which is arranged on the vehicle body and is in communication connection with the picking mechanism;

[0018] Furthermore, the mechanical arm is formed by a plurality of connecting arms connected in sequence, and two adjacent connecting arms are connected via a control motor to control the swing and / or rotation thereof.

[0019] Furthermore, the base of the robotic arm is connected to the vehicle body, the top of the robotic arm is connected to the grasping claw, and the control motor includes a first motor, a second motor, a third motor, a fourth motor and a fifth motor; the first motor controls the rotation of the grasping claw, the second motor, the third motor and the fourth motor control the swing of the connecting arm, and the fifth motor controls the rotation of the base.

[0020] Furthermore, a buffer material for protecting fruits and vegetables is provided on the inner side of the gripping claw.

[0021] Furthermore, the driving motor is a pneumatic motor, and the gripping portion further comprises a constant-pressure pneumatic circuit, which provides a constant torque for the driving motor so that the gripping claw can achieve flexible gripping.

[0022] Furthermore, the collection box is arranged in the interlayer space inside the vehicle body, and a baffle is provided at the opening thereof extending outwardly, so that the picked fruits and vegetables can slide through the baffle into the collection box.

[0023] Furthermore, the separation unit includes a laser generator, which can emit a laser with a corresponding power according to the diameter of the fruit stalk to cut off the fruit stalk.

[0024] In a second aspect, an embodiment of the present invention provides a picking method based on a picking robot, comprising:

[0025] The visual device of the picking robot obtains the location information of the target fruits and vegetables, controls the robot arm to plan the motion trajectory, and delivers the gripper to the initial picking point;

[0026] Adjust the position of the gripping claws so that the target fruits and vegetables are located at the center of the enclosed area formed by the gripping claws, and control the gripping claws to close so as to clamp and fix the target fruits and vegetables;

[0027] The separation unit is controlled to cut the fruit stems of the target fruits and vegetables.

[0028] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0029] The picking robot and the picking method provided by the embodiments of the present invention locate the positions of fruits, vegetables and fruit stems through machine vision when picking fruits and vegetables, and adopt a constant pressure circuit to drive the gripping claws to keep the gripping force of the gripping claws constant to achieve flexible gripping, avoid damage caused by excessive squeezing, and reduce the damage rate of fruits and vegetables; laser cutting is used to cut off the fruit stems to make the incision of the fruit stems smooth, reduce the risk of invasion of pathogenic microorganisms, and reduce the infection rate of the incision, thereby reducing the use of chemical preservatives and extending the shelf life. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural front view of the picking robot shown in an embodiment of the present invention;

[0031] Figure 2 A structural side view of a picking robot shown in an embodiment of the present invention;

[0032] Figure 3 Schematic diagram of a constant pressure pneumatic circuit of a picking robot shown in an embodiment of the present invention;

[0033] Figure 4 This is a flow chart of a picking method of a picking robot shown in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] Unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] The present invention provides a harvesting robot and a harvesting method thereof. The harvesting robot and the harvesting method of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0038] like Figure 1 and Figure 2 As shown, this embodiment provides a picking robot, including:

[0039] A traveling mechanism 1 ; the traveling mechanism 1 comprises: a vehicle body 110 .

[0040] In this embodiment, the traveling mechanism 1 may further include a traveling motor 120 to provide power for the vehicle body 110 .

[0041] In this embodiment, the walking mechanism 1 may further include wheels 130 to achieve the movement of the vehicle body 110 .

[0042] A collection box 2 is arranged on the vehicle body 110 .

[0043] In this embodiment, the collection box 2 is disposed in the inner interlayer space of the vehicle body 110 , and a baffle 210 is provided extending outward from the opening thereof so that the picked fruits and vegetables can enter the collection box 2 through the baffle.

[0044] Preferably, the baffle shown in this embodiment is tilted to form an angle with the horizontal ground. When the gripping claw releases the fruits and vegetables, the fruits and vegetables automatically slide / roll into the collection box 2 due to the effect of the angle.

[0045] A picking mechanism is provided on the vehicle body 110, and the picking mechanism comprises:

[0046] A robotic arm 3 has multiple degrees of freedom.

[0047] In this embodiment, the base of the robotic arm is connected to the vehicle body 110, and the top of the robotic arm is connected to the gripping claw.

[0048] In this embodiment, the robotic arm may be formed by connecting a plurality of connecting arms in sequence, and two adjacent connecting arms may be connected via a control motor to control their swing and / or rotation.

[0049] As a further improvement of the above embodiment, in one implementation, the control motor includes a first motor 310, a second motor 320, a third motor 330, a fourth motor 340 and a fifth motor 350; the first motor 310 controls the rotation of the grasping claw 410, the second motor 320, the third motor 330 and the fourth motor 340 control the swing of the connecting arm, and the fifth motor 350 controls the rotation of the base.

[0050] This embodiment realizes the five degrees of freedom of the robotic arm by using five motors such as a combination of rotary and linear joints, so that the robotic arm has higher flexibility and freedom, can adapt to various application scenarios and task requirements such as the gaps between tall and short fruit trees, achieves precise positioning and picking, and can enhance load capacity and stability.

[0051] A gripping portion 4 includes a gripping claw 410 and a driving motor 420, wherein the driving motor 420 is used to drive the gripping claw 410 to open and close.

[0052] Specifically, the grasping claw 410 includes a left claw 411 and a right claw 412, and the left claw 411 and the right claw 412 can rotate around their respective claw shafts 413. The left claw 411 and the right claw 412 are also provided with a gear 414, and the claw shaft 413 coincides with the center of the gear. The left claw 411 and the right claw 412 are linked by gear meshing to achieve opening and closing to clamp fruits and vegetables.

[0053] Furthermore, the driving motor can drive the gripper of any of the grippers to rotate around the axis 413, and can simultaneously drive the other gripper to rotate around its gripper axis 413 through the gear, thereby realizing the opening and closing of the grasping gripper 410.

[0054] Preferably, a buffer material for protecting fruits and vegetables is disposed on the inner side of the gripping claw 410 shown in this embodiment. The buffer material may be a flexible material such as sponge, rubber, or silica gel.

[0055] Those skilled in the art will understand that by providing a buffer material on the inner side of the gripping claw, the buffer material can absorb a large amount of impact energy, thereby reducing the breakage rate of fruits and vegetables, and the buffer material increases the contact area through microscopic deformation, thereby improving the anti-slip effect and the stability of clamping.

[0056] As a further improvement of the above embodiment, in one implementation, the driving motor 420 is a pneumatic motor, and the gripping portion 4 further includes a constant pressure pneumatic circuit 430, which provides a constant torque for the driving motor 420 to drive the gripping claw 410 to achieve flexible gripping.

[0057] Figure 3 A method for implementing a constant-pressure pneumatic circuit 430 is shown, including: a small air pump 431, which provides power for the pneumatic circuit; an oil mist collector 432, which adds lubricating oil to the compressed air and evenly atomizes it; a pressure reducing valve 433, which adjusts and stabilizes the pressure in the system for the pneumatic circuit; a pressure gauge 434, which is used to detect the pressure of the pneumatic circuit; an air filter 435, which purifies the air for the pneumatic circuit; a pipe joint 436, which is used to connect pipelines; a constant-pressure valve 437, which provides constant air pressure for the pneumatic circuit, thereby providing constant torque for the drive motor, so that the drive motor drives the gripping claw to achieve flexible gripping; and an electromagnetic reversing valve 438, which changes the direction of the airflow in the pneumatic circuit.

[0058] Those skilled in the art will appreciate that the pneumatic motor drive has a fast response speed, and can start and stop quickly, and is particularly suitable for occasions of frequent starting. At the same time, compared with general motors, pneumatic motors are usually lighter, smaller in size, easier to install and carry, and have a simple structure, which is easy to implement and maintain. A constant pressure circuit is used to maintain stable air pressure to ensure that the pneumatic motor outputs a constant torque under different loads, so as to achieve dynamic control of precise grasping force, so that the grasping claw 410 maintains a constant gripping force when clamping, thereby controlling the clamping force of the grasping claw 410 within the tolerable range of the fruit skin, reducing the damage rate of fruits and vegetables, and achieving flexible picking.

[0059] Furthermore, the pressure of the constant pressure valve in the constant pressure circuit can be adjusted by judging the type and maturity of the fruit through image recognition technology, combined with the preset pressure threshold database of fruit and vegetable crops, so as to dynamically adjust the clamping force to adapt to the picking of different fruit and vegetable crops. Here, the pressure value of the constant pressure valve corresponding to the experiment adjustment of fruits and vegetables of various types and / or maturity (eggplant, tomato, green pepper, etc.) can be obtained through the test method.

[0060] A visual device 5 is used to collect images of fruits and vegetables, process them in real time, and obtain the position information of fruits and vegetables and the diameter information of fruit stems.

[0061] In a feasible embodiment, the visual device 5 can be set on the robotic arm 3, for example, on a connecting arm connected to the grasping claw at the top of the robotic arm, and a bracket can also be set to support the visual device 5 to obtain more accurate image position information; in other embodiments, the visual device 5 can also be set on the vehicle body 110.

[0062] For example, the visual device shown in this embodiment can be a depth camera. Those skilled in the art can understand that the depth camera can use three technologies such as structured light method, time of flight method (ToF) or binocular stereo vision method to obtain the three-dimensional coordinates of the object. Each technology realizes the perception of depth information through different physical mechanisms and algorithms, and finally combines the two-dimensional image with the depth data to calculate the three-dimensional space coordinates of the object, which will not be described one by one here.

[0063] For example, edge detection technology can be used to identify the outline and boundary of the fruit stalk and extract edge information. Based on the extracted edge information, geometric measurement algorithms are used to calculate parameters such as the distance between edges to determine the diameter of the fruit stalk.

[0064] A separation part 6 is used to cut the fruit stem. The separation part includes a bracket 610 and a laser generator 620. The laser generator 620 can emit a laser with a corresponding power according to the diameter of the fruit stem to cut the fruit stem.

[0065] Specifically, the separation part 6 can be arranged on the robot arm, for example, the separation part 6 and the visual device 5 are arranged on the connecting arm connected to the gripping claw at the top of the robot arm. When cutting, first operate the robot arm to move to the front of the fruit and vegetable, control the connecting arm at the top of the robot arm to be horizontal, so that the visual device 5 is located directly above the connecting arm, and rotate the gripping claw to make it in a posture that is convenient for gripping; the visual device 5 determines the coordinates of the connection between the fruit stalk and the fruit and vegetable by the difference in color between the fruit stalk and the fruit and vegetable; then, through the visual device 5, control the gripping claw 410 to grip the fruit and vegetable, and control the laser generator 620 to emit laser lines at the connection between the fruit stalk and the fruit and vegetable for cutting. The height of the bracket 610 may be adjustable so that the laser generator 620 can be adjusted to align with the fruit stem and the connection between fruits and vegetables; the height of the bracket 610 may also be fixed. In this case, the gripping position of the gripping claw 410 is fixed relative to the coordinates of the connection between the fruit stem and the fruits and vegetables. By setting a certain height value of the bracket 610, the laser generator 620 can be aligned with the connection between the fruit stem and the fruits and vegetables for cutting.

[0066] Preferably, the picking robot shown in this embodiment further includes a control mechanism, which can be disposed on the vehicle body 110 and is communicatively connected with the picking mechanism.

[0067] In this embodiment, the control mechanism controls the movement of the first motor 310 , the second motor 320 , the third motor 330 , the fourth motor 340 , the fifth motor 350 , and the driving motor 120 , controls the laser generator 620 , and controls the opening, closing, and clamping of the gripping claw 410 .

[0068] Specifically, the control mechanism calculates the coordinates and motion trajectory that the grasping claw 410 is to reach based on the coordinates of the fruits, vegetables and fruit stalks, performs an inverse kinematic solution, calculates the angle that each motor needs to rotate, and then sends the angle information to the motor driver. The driver drives the output shafts of the first motor 310, the second motor 320, the third motor 330, the fourth motor 340, and the fifth motor 350 to rotate respectively, so that the grasping claw 410 reaches the position for grasping the fruits and vegetables; the control mechanism receives the fruit stalk diameter information calculated by the visual device 5, and sends a PWM voltage regulation signal to control the laser generator 620 to emit a laser of corresponding power to cut off the fruit stalk.

[0069] Specifically, when the constant pressure pneumatic circuit 430 is used to drive the pneumatic motor, the control mechanism controls the electromagnetic reversing valve 438 to be energized, so that the air circuit enters from the right and exits from the left, and the pneumatic motor rotates clockwise. The pneumatic motor drives the left claw 411, and the left claw 411 rotates around the claw axis (left). Through the engagement of the left claw 411 and the right claw 412 gear teeth, the right claw 412 is driven to rotate around the claw axis (right), thereby achieving the closure of the grasping claw 410; the control mechanism controls the electromagnetic reversing valve 438 to be de-energized, and the air circuit enters from the left and exits from the right, so that the grasping claw 410 is in an open state.

[0070] Optionally, the control mechanism may be an industrial computer or a single-chip microcomputer.

[0071] Optionally, the industrial computer or single chip microcomputer may be single or two or more to control different components / assemblies respectively.

[0072] like Figure 4 As shown, the present embodiment also provides a picking method of the picking robot as described above, comprising: S1, acquiring the position information of the target fruits and vegetables based on the visual device of the picking robot, controlling the robot arm to plan the motion trajectory, and delivering the gripping part to the initial picking point; S2, adjusting the position of the gripping claws so that the target fruits and vegetables are located at the center of the encircled area formed by the gripping claws, and controlling the gripping claws to close so as to clamp and fix the target fruits and vegetables; S3, controlling the separation part to cut the fruit stalks of the target fruits and vegetables.

[0073] Wherein, the initial picking point can be set right in front of the fruits and vegetables.

[0074] In some optional implementations, the above step S1 may further include: determining the coordinates of the connection between the fruit stalk and the fruits and vegetables based on the difference in color between the fruit stalk and the fruits and vegetables.

[0075] In some optional implementations, the above step S1 may further include: determining the coordinates of the grasping position of the grasping claw based on the position information of the fruits and vegetables.

[0076] In some optional embodiments, the above step S1 may further include: determining the coordinates of the gripping position of the gripping claw based on the coordinates of the fruit stalk and the connection between the fruit and vegetable. For example, the gripping position of the gripping claw may be fixed relative to the coordinates of the connection between the fruit stalk and the fruit and vegetable to reduce the complexity of component design.

[0077] In some optional embodiments, the above step S2 may also include: controlling the connecting arm at the top of the robotic arm to be horizontal, and rotating the grasping claw to put it in a posture that is convenient for grasping.

[0078] In some optional embodiments, adjusting the position of the grasping claw so that the target fruits and vegetables are located at the center of the enclosed area formed by the grasping claw includes: controlling the grasping claw to reach directly below (or directly above) the target fruits and vegetables, and moving from directly below the target fruits and vegetables from bottom to top (or from directly above from top to bottom) until the target fruits and vegetables are located at the center of the enclosed area formed by the grasping claw.

[0079] In some optional embodiments, the above step S2 may also include: judging the type and maturity of the fruit by image recognition technology, and adjusting the gripping force of the gripping claws gripping the fruit and vegetables accordingly in combination with a preset pressure threshold database of fruit and vegetable crops. For example, fruits and vegetables (eggplants, tomatoes, green peppers, etc.) of various types and / or maturity may be obtained by experimental method, and experimental adjustments may be made to obtain the corresponding pressure value of the constant pressure valve.

[0080] In some optional embodiments, the picking method may further include: S4, controlling the robotic arm to move the fruits and vegetables to the baffle in a fixed moving program route for storing fruits and vegetables, and releasing the gripping claws to allow the fruits and vegetables to enter the collection box along the baffle.

[0081] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0082] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A picking robot, characterized in that: include: A walking mechanism; a collection box; A picking mechanism, the picking mechanism comprising: A robotic arm having multiple degrees of freedom; A gripping portion, comprising a gripping claw and a driving motor, wherein the driving motor is used to drive the gripping claw to open and close; A visual device for collecting images of fruits and vegetables, processing them in real time, and obtaining position information and stem diameter information of fruits and vegetables; A separation part is used for cutting the fruit stem.

2. The harvesting robot according to claim 1, characterized in that: The walking mechanism comprises: A vehicle body; wherein the picking mechanism and the collecting box are both arranged on the vehicle body.

3. The harvesting robot according to claim 1, characterized in that: It also includes a control mechanism, which is arranged on the vehicle body and is in communication connection with the picking mechanism.

4. The harvesting robot according to claim 1, characterized in that: The mechanical arm is formed by connecting a plurality of connecting arms in sequence, and two adjacent connecting arms are connected via a control motor to control the swing and / or rotation thereof.

5. The harvesting robot according to claim 4, characterized in that: The base of the robotic arm is connected to the vehicle body, the top of the robotic arm is connected to the grasping claw, and the control motor includes a first motor, a second motor, a third motor, a fourth motor and a fifth motor; the first motor controls the rotation of the grasping claw, the second motor, the third motor and the fourth motor control the swing of the connecting arm, and the fifth motor controls the rotation of the base.

6. The harvesting robot according to claim 1, characterized in that: The inner side of the gripping claw is provided with a buffer material for protecting fruits and vegetables.

7. The harvesting robot according to claim 1, characterized in that: The driving motor is a pneumatic motor, and the gripping part further comprises a constant pressure pneumatic circuit, which provides a constant torque for the driving motor to drive the gripping claw to achieve flexible gripping.

8. The harvesting robot according to claim 1, characterized in that: The collection box is arranged in the interlayer space inside the vehicle body, and a baffle is arranged at the opening thereof extending outwardly, so that the picked fruits and vegetables can enter the collection box through the baffle.

9. The harvesting robot according to claim 1, characterized in that: The separation unit includes a laser generator, which can emit laser light of corresponding power according to the diameter of the fruit stalk to cut off the fruit stalk.

10. A picking method using a picking robot according to any one of claims 1 to 9, characterized in that: include: The visual device of the picking robot obtains the location information of the target fruits and vegetables, controls the robot arm to plan the motion trajectory, and delivers the gripper to the initial picking point; Adjust the position of the gripping claws so that the target fruits and vegetables are located at the center of the enclosed area formed by the gripping claws, and control the gripping claws to close so as to clamp and fix the target fruits and vegetables; The separation unit is controlled to cut the fruit stems of the target fruits and vegetables.

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