A multi-modal fruit and vegetable picking end effector

Abstract

The application discloses a multi-mode fruit and vegetable picking end effector. The application comprises a mounting base, a first driving assembly, a second driving assembly, a first connecting block, a connecting rod, guide strips, a second connecting block, a sucker connecting block and a clamping finger sucker. The first driving assembly is fixedly installed in the mounting base, the second driving assembly is fixedly connected with the first driving assembly through the connecting rod, a plurality of guide strips are slidingly installed at the outer side of the second driving assembly, the output shaft of the first driving assembly is fixedly connected with one end of the plurality of guide strips through the first connecting block, the other end of the plurality of guide strips is fixedly connected with the outside of the clamping finger sucker through the sucker connecting block, and the output shaft of the second driving assembly is fixedly connected with the inside of the clamping finger sucker through the second connecting block. The end effector has multiple working modes through the cooperation of the two driving assemblies and the air circuit, different working modes are adopted for different types of fruits and vegetables, and the picking of multiple types of fruits and vegetables is realized.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of agricultural picking robots, and particularly relates to a multi-mode fruit and vegetable picking end effector. BACKGROUND

[0002] Fruit and vegetables are the main components of food in human diet, rich in vitamins, inorganic salts and dietary fiber necessary for the human body, and are necessities in human life. Traditional fruit and vegetable picking methods are inefficient and labor-intensive, and with the aging of the agricultural workforce and the shortage of agricultural labor, the cost of labor is further increased. In order to solve the above problems, robot technology begins to be applied in agricultural production, and fruit and vegetable picking automation has become an effective solution to reduce costs and increase efficiency.

[0003] Robot technology in agricultural production faces some challenges and difficulties, such as high cost. At the same time, the existing fruit and vegetable picking end effector is highly targeted, that is, the working object is mostly fixed, and can only realize the picking of a certain crop, and does not have universality. There are many types of fruits and vegetables, and there is an urgent need for a picking end effector to realize the picking of multiple fruits and vegetables, reduce the hardware cost of agricultural robots, promote the application and development of agricultural robots, and solve the problems of labor shortage and high labor cost. SUMMARY

[0004] In view of the above technical problems, the purpose of the present application is to provide a multi-mode fruit and vegetable picking end effector, that is, to realize the picking of multiple fruits and vegetables in the face of different fruits and vegetables. The end effector has multiple working modes, and in the face of different types of fruits and vegetables, different working modes are adopted to realize the picking of multiple types of fruits and vegetables.

[0005] In order to achieve the above purpose, the present application provides the following technical solutions:

[0006] I. A multi-mode fruit and vegetable picking end effector

[0007] The end effector comprises a mounting base, a first driving assembly, a second driving assembly, a first connecting block, a connecting rod, an air pipe, a guide strip, a second connecting block, a sucker connecting block and a finger sucker; the first driving assembly is fixedly installed in the mounting base, the second driving assembly is fixedly connected with the first driving assembly through the connecting rod, a plurality of guide strips are slidably installed at the outer side surface of the second driving assembly, the plurality of guide strips are arranged in parallel, the output shaft of the first driving assembly is fixedly connected with one end of the plurality of guide strips through the first connecting block, the other end of the plurality of guide strips is fixedly connected with the outside of the finger sucker through the sucker connecting block, the output shaft of the second driving assembly is fixedly connected with the inside of the finger sucker through the second connecting block, and the air pipe is arranged in the finger sucker; the movement of the first driving assembly and / or the second driving assembly changes the relative position between the sucker connecting block and the second connecting block, so that the inside of the finger sucker is deformed, the area of the fruit and vegetable contact end surface of the finger sucker is changed, and the picking action of the target fruit and vegetable is completed.

[0008] The finger sucker comprises an outer ring, an inner ring, a pipe, a finger and a sucker; the outer edge of the outer ring is fixedly connected with the sucker connecting block, the inner edge of the outer ring extends inward and is fixedly connected with the middle part of the inner ring, one end of the inner ring is fixedly connected with the second connecting block, the other end of the inner ring is fixedly connected with the sucker, the pipe is arranged in the inside of the inner ring, the air pipe is arranged in the pipe, and the sucker and the outer edge of the outer ring are connected through the plurality of fingers; the relative movement between the sucker connecting block and the second connecting block causes the deformation of the connection part of the outer ring and the inner ring, and then drives the deformation of the sucker and the finger, and finally changes the area of the fruit and vegetable contact end surface of the sucker.

[0009] The diameter of the connection part of the inner ring and the outer ring is smaller than the diameter of the connection part of the inner ring and the second connecting block.

[0010] The plurality of guide strips are arranged at equal intervals along the circumference.

[0011] The mounting base is a flange mounting base, which is directly connected with the end of the mechanical arm or connected with the end of the mechanical arm through the flange mounting base.

[0012] The first driving assembly and the second driving assembly are both air cylinders.

[0013] The fruit and vegetable contact end surface of the finger sucker is further provided with a sponge.

[0014] The output shaft of the second driving assembly is always kept stationary, the output shaft of the first driving assembly is gradually extended, the fruit and vegetable contact end surface of the finger sucker is deformed and its area is gradually reduced, the fruit and vegetable contact end surface is more closely attached to the surface of the fruit and vegetable, and greater adsorption force is provided.

[0015] When the output shaft of the second drive component is in an extended state, after the finger-gripping suction cup contacts and adsorbs the target fruit, the output shaft of the second drive component retracts, so that while the end effector itself remains stationary, the target fruits and vegetables are attracted away from the fruit cluster, and the finger-gripping suction cup holds the target fruit more stably during the retraction process.

[0016] 2. A picking device

[0017] The picker includes the multi-mode fruit and vegetable picking end effector.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The end effector designed in the present invention combines the features of the finger-gripping end effector and the adsorption end effector, and can realize both the clamping function and the adsorption function, as well as the suction-clamping composite function.

[0020] 2. The end effector designed in the present invention has multiple working modes. When facing fruits of different sizes, different working modes are adopted to realize the picking of multiple types of fruits and vegetables. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the overall structure of the multi-mode fruit and vegetable picking end effector of the present invention;

[0022] Figure 2 is a cross-sectional view of the end effector;

[0023] Figure 3 It is a structural diagram of the end effector in different working modes.

[0024] In the figure: 1. flange mounting seat, 2. first cylinder, 3. first connecting block, 4. connecting rod, 5. second cylinder, 6. air pipe, 7. guide bar, 8. second connecting block, 9. suction cup connecting block, 10. finger suction cup, 11. sponge. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the accompanying drawings and examples.

[0026] like Figure 1 and Figure 2As shown, the multi-mode fruit and vegetable picking end effector provided by the present application comprises a mounting base, a first driving assembly, a second driving assembly, a first connecting block 3, a connecting rod 4, an air pipe 6, a guide strip 7, a second connecting block 8, a sucker connecting block 9 and a finger sucker 10. The mounting base is a flange mounting seat 1, which is directly connected with the end of the mechanical arm. The first driving assembly is fixedly installed in the mounting base, and the second driving assembly is fixedly connected with the first driving assembly through the connecting rod 4. The connecting rod 4 can be a toothed rod. The second driving assembly and the mounting base are respectively arranged at two ends of the first driving assembly. The first driving assembly and the second driving assembly are arranged at intervals. The output shafts (i.e. the piston rods of the air cylinders) of the first driving assembly and the second driving assembly are coaxially arranged, and the driving direction is parallel to the sliding direction of the guide strip 7. The first driving assembly and the second driving assembly are both air cylinders, which are respectively denoted as the first air cylinder 2 and the second air cylinder 5. A plurality of guide strips 7 are slidingly installed at the outer side of the second driving assembly, and the plurality of guide strips 7 are arranged at equal intervals along the circumference. The plurality of guide strips 7 are arranged in parallel. A plurality of through holes are formed in the inside of the first connecting block 3, and the plurality of guide strips 7 are arranged in the through holes of the first connecting block 3. The output shaft of the first driving assembly is fixedly connected with one end of the plurality of guide strips 7 through the first connecting block 3. The other end of the plurality of guide strips 7 is fixedly connected with the outside of the finger sucker 10 through the sucker connecting block 9. The output shaft of the second driving assembly is fixedly connected with the inside of the finger sucker 10 through the second connecting block 8. There is a contact surface between the sucker connecting block 9 and the second connecting block 8, and the two are slidingly arranged. The air pipe 6 is arranged in the finger sucker 10, and the air pipe 6 is in communication with an externally arranged air path. The movement of the first driving assembly and / or the second driving assembly changes the relative position between the sucker connecting block 9 and the second connecting block 8, so that the inside of the finger sucker 10 is deformed, thereby changing the area size of the fruit and vegetable contact end face of the finger sucker 10, and completing the picking action of the target fruit and vegetable.

[0027] The clamp finger suction cup 10 comprises an outer ring 101, an inner ring 102, a pipeline 103, clamp fingers 104, and a suction cup 105. The outer edge of the outer ring 101 is fixedly connected with the suction cup connecting block 9 through a bolt. The inner edge of the outer ring 101 extends inward and is fixedly connected with the middle part of the inner ring 102. One end of the inner ring 102 is fixedly connected with the second connecting block 8 through a bolt. The other end of the inner ring 102 is fixedly connected with the suction cup 105. The diameter of the connection between the inner ring 102 and the outer ring 101 is smaller than the diameter of the connection between the inner ring 102 and the second connecting block 8, that is, the diameter of the inner ring 102 gradually increases in the direction close to the second connecting block 8. The inner part of the inner ring 102 is provided with the pipeline 103, and the pipeline 103 is provided with the air pipe 6. The suction cup 105 and the outer edge of the outer ring 101 are also connected through a plurality of clamp fingers 104. The fruit and vegetable contact end surface of the clamp finger suction cup 10 is also provided with a sponge 11. The sponge 11 is adhered to the bottom surface of the suction cup 105 of the clamp finger suction cup 10, which can enhance the adsorption force and reduce the damage to fruits and vegetables during work. The relative movement between the suction cup connecting block 9 and the second connecting block 8 causes the deformation of the connection between the outer ring 101 and the inner ring 102, and further causes the deformation of the suction cup 105 and the clamp fingers 104, so as to finally change the size of the fruit and vegetable contact end surface of the suction cup 105. The outer ring 101 plays a connecting role and is one of the stress areas of the deformation of the clamp finger suction cup 10, and the stress comes from the first air cylinder 2. The wall thickness of the contact area between the outer ring 101 and the suction cup connecting block 9 is greater than the area where the outer ring 101 is connected with the inner ring 102 and the suction cup 105, so that the area around the outer ring 101 connected with the inner ring 102 and the suction cup 105 deforms and the contact area between the outer ring 101 and the suction cup connecting block 9 does not deform in the working state. The inner ring 102 plays a connecting role and is another stress area of the deformation of the clamp finger suction cup 10, and the stress comes from the second air cylinder 5. The diameter of the connection end of the inner ring 102 and the second connecting block 8 is greater than the diameter of the connection end of the inner ring 102 and the outer ring 101 and the suction cup 105, so that the area around the outer ring 101 connected with the inner ring 102 and the suction cup 105 deforms and the inner ring 102 does not deform in the working state. The diameter of the connection end of the inner ring 102 and the outer ring 101 and the suction cup 105 is greater than the diameter of the pipeline 103. The diameter of the suction cup 105 is smaller than the outer diameter of the outer ring 101, so that the two clamp fingers 104 symmetrically distributed are distributed at a certain angle in the natural state. In the enhanced suction cup mode and the clamping mode, the outer ring 101 is subjected to the thrust of the first air cylinder 2 and moves away from the first air cylinder 2, forcing the surrounding inner recess of the outer ring 101 connected with the inner ring 102 and the suction cup to deform, the clamp fingers 104 to bend and deform, and the suction cup 105 to bend and deform. In the air suction and clamping combined mode, the inner ring 102 is subjected to the tension of the second air cylinder 5 and moves toward the second air cylinder 5, forcing the surrounding inner recess of the outer ring 101 connected with the inner ring 102 and the suction cup to deform, the clamp fingers 104 to bend and deform, and the suction cup 105 to bend and deform.

[0028] The output shaft of the second driving assembly is always kept stationary, and the output shaft of the first driving assembly is gradually extended, i.e. moves close to the fingered suction cup 10, so that the fruit and vegetable contact end face of the fingered suction cup 10 is deformed and its area gradually becomes smaller, so that it is more closely attached to the surface of the fruit and vegetable, and provides greater adsorption force.

[0029] When the output shaft of the second driving assembly is in the extended state, after the fingered suction cup 10 contacts the target fruit and vegetable, the output shaft of the second driving assembly is retracted, i.e. moves away from the fingered suction cup 10, so that the target fruit and vegetable is attracted away from the fruit cluster while keeping the end effector itself stationary, and the fingered suction cup 10 more stably holds the target fruit and vegetable during the retraction process.

[0030] In this embodiment, as shown in Figure 3 the piston rod of the second cylinder 5 is in the extended state in the initial state; the piston rod of the first cylinder 2 is in the retracted state in the initial state. In the clamping mode, the diameter of the suction cup is greater than half the circumference of the cross section of the fruit and vegetable, and the wrapping clamping can be achieved; in the suction cup mode, the diameter of the suction cup is smaller than half the circumference of the cross section of the fruit and vegetable, and effective wrapping clamping cannot be achieved, and only the fruit and vegetable can be adsorbed.

[0031] The end effector has five working modes, namely, a normal suction cup mode, an enhanced suction cup mode, a normal clamping mode, a suction and clamping composite mode and an attraction and clamping mode. The normal suction cup mode and the enhanced suction cup mode can realize the fruit and vegetable adsorption and grabbing of the half of the cross-sectional circumference of the fruit and vegetable contact surface being greater than the diameter of the suction cup, wherein the normal suction cup mode is suitable for the fruit and vegetable with the half of the cross-sectional circumference of the fruit and vegetable contact surface being much greater than the diameter of the suction cup, that is, the suction cup contact end surface does not deform, only the sponge deforms, can be closely combined with the fruit and vegetable contact surface, and forms a strong adsorption force. When the suction cup cannot be closely combined with the fruit and vegetable surface in the normal suction cup mode, the enhanced suction cup mode is used, the suction cup contact end surface deforms and is closely combined with the fruit and vegetable surface, and a strong adsorption force is formed. The normal clamping mode, the suction and clamping composite mode and the attraction and clamping mode can realize the fruit and vegetable wrapping and clamping of the half of the cross-sectional circumference of the fruit and vegetable contact surface being less than the diameter of the suction cup, wherein the normal clamping mode is suitable for the fruit and vegetable with the cross-sectional circumference of the fruit and vegetable contact surface being less than or equal to the diameter of the suction cup, that is, the fruit and vegetable can be completely wrapped and clamped, at this time, the adsorption force provided by the suction cup is not needed and stable clamping can be realized. When the fruit and vegetable cannot be completely wrapped and clamped, in order to ensure the reliability of clamping, the air path can be opened on the basis of the normal clamping mode to form the suction and clamping composite mode, so that the suction cup works and an additional adsorption force is provided. In addition, there is also an attraction and clamping mode, which is suitable for the fruit cluster picking scene. In this scene, the working space cannot be provided for the normal clamping mode or the suction and clamping composite mode, and the picking work cannot be carried out without interfering with the adjacent fruits, so it is necessary to first move the target fruit away from the fruit cluster by a distance to form a working space. The attraction and clamping mode can realize this demand, in this mode, the target fruit is first adsorbed, and then the target fruit is moved away from the fruit cluster, and the suction cup deforms to wrap and clamp the target fruit during the moving away process.

[0032] As shown in Figure 3 , the four working modes of the end effector are the normal suction cup mode (a of Figure 3 ), the enhanced suction cup mode (b of Figure 3 ), the normal clamping mode (c of Figure 3 ), the suction and clamping composite mode (d of Figure 3 ) and the attraction and clamping mode (e of Figure 3 ). As shown in Figure 3 a, when the half of the cross-sectional circumference of the fruit and vegetable contact surface is much greater than the diameter of the suction cup, that is, the suction cup can be closely combined with the fruit and vegetable surface to form a closed space without deformation, the normal suction cup mode is adopted, that is, the first air cylinder and the second air cylinder do not work, the end effector is directly close to the surface of the fruit after ventilation, and adsorption and grabbing are realized, and then a twisting action is realized to realize picking; as shown in Figure 3b, when the ordinary suction cup mode cannot effectively adhere to the surface of the fruit and vegetable to form a closed space to complete the adsorption, the enhanced suction cup mode is used, that is, the end effector gas circuit is opened, the sponge of the finger suction cup contacts the surface of the fruit and vegetable, and then the first cylinder works, the piston rod of the first cylinder extends, the outer ring of the finger suction cup moves away from the flange mounting seat, the outer ring 101, the finger 104 and the suction cup 105 of the finger suction cup 10 are deformed, the suction cup and the sponge are tightly attached to the surface of the fruit and vegetable, the adsorption and grabbing are realized, and then the twisting action is realized to realize picking; as shown in Figure 3 c, when the circumference of the cross section of the fruit and vegetable contacting surface is less than or equal to the diameter of the suction cup, that is, the fruit and vegetable can be completely wrapped and clamped, the ordinary clamping mode can be adopted, that is, the sponge of the finger suction cup contacts the surface of the fruit and vegetable, and then the first cylinder works, the piston rod of the first cylinder extends, the outer ring of the finger suction cup moves away from the flange mounting seat, the outer ring 101, the finger 104 and the suction cup 105 of the finger suction cup 10 are deformed, the suction cup and the sponge are tightly wrapped around the surface of the fruit and vegetable, the clamping and grabbing are realized, and then the pulling action is realized to realize picking; as shown in Figure 3 d, when the fruit and vegetable cannot be completely wrapped and clamped, in order to ensure the reliability of clamping, the gas circuit can be opened on the basis of the ordinary clamping mode to form an adsorption and clamping composite mode, that is, the end effector gas circuit is opened, the sponge of the finger suction cup contacts the surface of the fruit and vegetable, and then the first cylinder works, the piston rod of the first cylinder extends, the outer ring of the finger suction cup moves away from the flange mounting seat, the outer ring 101, the finger 104 and the suction cup 105 of the finger suction cup 10 are deformed, the suction cup and the sponge are tightly adsorbed and wrapped around the surface of the fruit and vegetable, and then the twisting action is realized to realize picking; as shown in Figure 3 e, when the target fruit is located in a fruit cluster, due to the limited working space, the clamping mode or the adsorption and clamping composite mode is not only easy to fail picking, but also easy to damage the adjacent fruit, therefore, the suction and clamping mode is adopted, that is, the end effector gas circuit is opened, the sponge of the finger suction cup contacts the surface of the fruit and vegetable, and then the adsorption is completed, the second cylinder works, the piston rod of the second cylinder retracts, the inner ring 102 of the finger suction cup moves toward the flange mounting seat, the outer ring 101, the finger 104 and the suction cup 105 of the finger suction cup 10 are deformed, the suction cup and the sponge are tightly adsorbed and wrapped around the surface of the fruit and vegetable, and then the twisting action is realized to realize picking; as shown in

[0033] For example, when the diameter of the suction cup is similar to the diameter of medium-sized fruits such as cucumbers and small oranges, the ordinary suction cup mode is used to realize the adsorption and picking of large-sized fruits such as apples, oranges and sweet peppers, and the twisting action is used to realize the picking; for medium-sized fruits, the enhanced suction cup mode is used to realize the adsorption and picking, and the twisting action is used to realize the picking; for extremely small-sized fruits such as beans, the clamping mode is used to realize the clamping and picking, and the pulling action is used to realize the picking; for small-sized fruits such as hawthorn fruits, the adsorption and clamping combined mode is used to realize the adsorption and clamping combined picking, and the twisting or pulling action is used to realize the picking; for small-sized fruit clusters such as cherry tomatoes, the suction and clamping mode is used to realize the suction and clamping combined picking, the damage to adjacent fruits or leaves is reduced, and the twisting or pulling action is used to realize the picking; in addition, the suction and clamping mode can also be used to remove old leaves of leafy vegetables.

[0034] Finally, it should be pointed out that the above examples and descriptions are only used to illustrate the technical solutions of the present application and not to limit the present application. Those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions disclosed by the present application, and all of them should be covered in the protection scope of the claims of the present application.

Claims

1. A multi-mode fruit and vegetable picking end effector, characterized in that: The invention comprises a mounting base, a first drive assembly, a second drive assembly, a first connecting block (3), a connecting rod (4), an air pipe (6), a guide bar (7), a second connecting block (8), a suction cup connecting block (9) and a finger-clamping suction cup (10); the first drive assembly is fixedly mounted in the mounting base, the second drive assembly is fixedly connected to the first drive assembly via the connecting rod (4), a plurality of guide bars (7) arranged at intervals are slidably mounted on the outer side surface of the second drive assembly, the plurality of guide bars (7) are arranged in parallel, and the output shaft of the first drive assembly is fixedly connected to one end of the plurality of guide bars (7) via the first connecting block (3). The other ends of the plurality of guide bars (7) are fixedly connected to the outside of the finger-clamping sucker (10) through the sucker connecting block (9), and the output shaft of the second driving component is fixedly connected to the inside of the finger-clamping sucker (10) through the second connecting block (8), and an air pipe (6) is provided in the finger-clamping sucker (10); the movement of the first driving component and / or the second driving component changes the relative position between the sucker connecting block (9) and the second connecting block (8), so that the inside of the finger-clamping sucker (10) is deformed, thereby changing the area of ​​the fruit and vegetable contact end surface of the finger-clamping sucker (10), and completing the picking action of the target fruit and vegetable; The finger-gripping suction cup (10) comprises an outer ring (101), an inner ring (102), a pipeline (103), a finger-gripping suction cup (104), and a suction cup (105); the outer edge of the outer ring (101) is fixedly connected to the suction cup connecting block (9), the inner edge of the outer ring (101) extends inwardly and is fixedly connected to the middle of the inner ring (102), one end of the inner ring (102) is fixedly connected to the second connecting block (8), the other end of the inner ring (102) is fixedly connected to the suction cup (105), and the inner ring (102) is fixedly connected to the suction cup (105). A pipeline (103) is provided inside, an air pipe (6) is provided inside the pipeline (103), and the suction cup (105) and the outer edge of the outer ring (101) are connected by a plurality of clamping fingers (104); the relative movement between the suction cup connecting block (9) and the second connecting block (8) causes the connection between the outer ring (101) and the inner ring (102) to deform, thereby driving the suction cup (105) and the clamping fingers (104) to deform, and finally changing the area of ​​the fruit and vegetable contact end surface of the suction cup (105); The output shaft of the second drive assembly remains stationary, and the output shaft of the first drive assembly gradually extends, causing the fruit and vegetable contact end surface of the finger-gripping suction cup (10) to deform and its area to gradually decrease.

2. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: The diameter of the connection between the inner ring (102) and the outer ring (101) is smaller than the diameter of the connection between the inner ring (102) and the second connection block (8).

3. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: The plurality of guide bars (7) are arranged at equal intervals along the circumference.

4. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: The mounting base is a flange mounting base, which is directly connected to the end of the robotic arm, or the mounting base is connected to the end of the robotic arm through the flange mounting base.

5. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: The first driving assembly and the second driving assembly are both cylinders.

6. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: A sponge (11) is also provided at the fruit and vegetable contact end surface of the finger-gripping suction cup (10).

7. The multi-mode fruit and vegetable picking end effector according to claim 1, characterized in that: When the output shaft of the second drive assembly is in an extended state, after the finger-gripping suction cup (10) contacts and adsorbs the target fruit, the output shaft of the second drive assembly retracts, so that the finger-gripping suction cup (10) can more stably grip the target fruit during the retraction process while keeping the end effector itself stationary.

8. A picking device, characterized in that: The picker comprises a multi-mode fruit and vegetable picking end effector according to any one of claims 1-7.

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