End effector for removing abnormal leaves of hydroponic lettuce

Abstract

The invention discloses an end effector for removing abnormal leaves of hydroponic lettuce. The end effector is used for identifying and positioning the hydroponic lettuce and abnormal leaves through a camera and a correlation type photoelectric switch; the action of the executing mechanism is controlled through 180-degree reciprocating rotation of the driving mechanism, and self-adaptive grabbing and overturning removal of abnormal blades are achieved. And the execution mechanism realizes flexible grabbing of abnormal blades through a pneumatic claw. The device is suitable for the hydroponic lettuce in a free state and an inverted posture, can efficiently and accurately remove abnormal leaves of the hydroponic lettuce, and has the characteristics of high adaptability and simplicity in operation.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural automation and robotics and relates to an end effector, in particular to an end effector used for removing abnormal leaves of hydroponic lettuce. Background Art

[0002] Hydroponic lettuce has become an important direction for urban agriculture and factory planting due to its advantages such as short growth cycle, high space utilization and no soil-borne diseases. However, during the growth of hydroponic lettuce, some leaves may become abnormal (such as yellowing, wilting, spots, etc.) due to factors such as diseases, nutritional imbalance or environmental changes. When harvesting hydroponic lettuce, it is necessary to remove abnormal leaves after removing the roots and sponge blocks to ensure the commercial quality of the lettuce. Traditional manual removal is inefficient, labor-intensive and costly, and it is difficult to adapt to the needs of large-scale production.

[0003] In recent years, agricultural automation and robotics have been widely used in the sowing, transplanting, management and harvesting of hydroponic lettuce, but their application in the removal of abnormal leaves of hydroponic lettuce is still in its infancy. Existing end effectors usually target the entire lettuce plant, and their structure and function cannot meet the needs of precise removal of single leaves.

[0004] Therefore, an end effector specifically for removing abnormal leaves of hydroponic lettuce was developed. Summary of the invention

[0005] In view of the problems and needs existing in the background technology, the purpose of the present invention is to provide an end effector for removing abnormal leaves of hydroponic lettuce. The present invention combines multi-sensor fusion with a bionic clamping structure to achieve rapid identification and removal of abnormal leaves through low-invasive operations, while reducing interference with healthy leaves, and meeting the technical requirements of efficient and precise management of factory production of hydroponic lettuce. The end effector proposed in the present invention can not only improve the production quality of hydroponic lettuce, realize efficient, accurate and automated leaf management, but also reduce manual intervention, further promote the intelligent and refined development of agricultural production, and has important practical significance and broad market demand.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] 1. An end effector for removing abnormal leaves of hydroponic lettuce

[0008] The end effector includes a frame, a sensing system, an actuator and a driving mechanism; the sensing system is installed in the frame and the actuator and is used to sense the hydroponic lettuce; the driving mechanism is fixedly installed in the frame; the actuator is connected to the driving mechanism; the driving mechanism drives the actuator to achieve the removal of abnormal leaves of the hydroponic lettuce.

[0009] The frame comprises a mechanical arm mounting plate and profiles; a plurality of profiles are connected to form a main frame, and the mechanical arm mounting plate is fixedly mounted on the main frame.

[0010] The sensing system includes a through-beam photoelectric switch and a camera, wherein the through-beam photoelectric switch is installed at the bottom of the frame, and the camera is installed on the actuator; wherein the through-beam photoelectric switch is used to detect the relative position between the end actuator and the top of the target lettuce, and the camera is used to detect the leaf state of the target lettuce.

[0011] The driving mechanism includes a limit shaft, a cylinder mounting plate, a limit cylinder, a rotating cylinder, a second stopper, a first bearing, a second bearing, a rotating mounting seat and a double-sided driving shaft; the cylinder mounting plate is fixedly connected to the side of the frame, the rotating cylinder is fixedly installed in the cylinder mounting plate, and the limit cylinder is fixedly installed in the cylinder mounting plate above the rotating cylinder. The limit cylinder and the rotating cylinder are arranged at intervals up and down and the output shafts of both are facing the inside of the frame. The output shaft of the limit cylinder is coaxially fixedly connected with the limit shaft, and the end face of the limit shaft is provided with an arc-shaped protrusion block for cooperating with the actuator to realize the starting limit of the actuator; a bearing mounting seat is fixedly installed at the end face of the cylinder mounting plate close to the inside of the frame, the double-sided driving shaft is installed in the bearing mounting seat through the second bearing and the cylindrical end of the double-sided driving shaft is coaxial with the output shaft of the rotating cylinder Fixed connection; the rotating mounting seat is installed outside the bearing mounting seat through the first bearing, and the actuator is fixedly connected to the rotating mounting seat; an arc-shaped protrusion block is provided on the end face of the double-sided driving shaft away from the rotating cylinder, and the inner hole of the rotating mounting seat away from the end of the rotating cylinder is a special-shaped hole, which is formed by splicing a semicircular hole and a semi-elliptical hole, and the radius of the semicircular hole is larger than the short semi-axis of the semi-elliptical hole, and two step surfaces are formed between the semicircular hole and the semi-elliptical hole and are respectively recorded as the second working surface and the third working surface, the arc-shaped protrusion block is arranged in the semicircular hole, the central angle of the arc-shaped protrusion block is less than 180 degrees, and the two side faces of the arc-shaped protrusion block are respectively recorded as the sixth working surface and the seventh working surface; a second stop block is also installed on the side of the bottom of the cylinder mounting plate away from the limiting cylinder, which is used to cooperate with the rotating mounting seat to realize the rotation limit of the actuator.

[0012] The actuator includes a pneumatic gripper, a gripper mounting plate and a first stopper; the gripper mounting plate is fixedly connected to the driving mechanism, a sensing system is installed on the lower surface of the gripper mounting plate, a first stopper is fixed on a side of the gripper mounting plate close to the frame, the first stopper cooperates with the driving mechanism to realize the starting limit of the actuator; a pneumatic gripper is also installed in the gripper mounting plate.

[0013] The gripper mounting plate is provided with a plurality of mounting holes for adjusting the mounting position of the pneumatic gripper.

[0014] 2. A method for removing abnormal leaves of hydroponic lettuce using the end effector

[0015] Step 1: Install the end effector at the end of the robotic arm, use the camera of the perception system to collect and process images, and adjust the position of the end effector according to the image detection results until the end effector moves to the top of the target lettuce;

[0016] Step 2: Use the camera of the perception system to collect images again and perform image processing. If there are abnormal leaves in the target lettuce, execute step 3; otherwise, move the end effector to the next lettuce and execute step 1;

[0017] Step 3: Drive the robotic arm to move the end effector vertically downward and close to the target lettuce until the opposing photoelectric switch has a signal; control the limit cylinder of the drive mechanism to release the limit on the actuator, the actuator rotates downward, the actuator contacts and grabs the abnormal leaves, and the drive mechanism controls the actuator to rotate upward in the opposite direction, so that the abnormal leaves are separated from the body of the target lettuce and the abnormal leaves are moved to the waste box; the drive mechanism continues to control the actuator to remove the abnormal leaves until all the abnormal leaves are removed.

[0018] 3. A device

[0019] The device comprises the end effector.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Adaptive grasping: The actuator relies on gravity to achieve adaptive adjustment within a 90-degree range, which can adapt to lettuces of different sizes. This not only reduces the control difficulty, but also significantly improves the versatility and adaptability of the end effector.

[0022] 2. Flexible grasping: The pneumatic gripper design is used to accurately clamp the petioles of abnormal leaves through a flexible grasping method, effectively avoiding the mechanical damage to the plants caused by the traditional rigid grasping method and protecting the growth integrity of the lettuce.

[0023] 3. Bionic operation: An anthropomorphic control strategy of the "pinch-flip" compound action is proposed, which can realize the removal of abnormal leaves of hydroponic lettuce in a free state and inverted posture, simulating manual operation while improving the reliability and efficiency of the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the end effector for removing abnormal leaves of hydroponic lettuce according to the present invention;

[0025] Figure 2 It is a schematic diagram of the structure of the actuator;

[0026] Figure 3 It is a structural diagram of the driving mechanism;

[0027] Figure 4 It is a schematic diagram of the action process of the end effector;

[0028] In the figure: 1. rack, 101. robot arm mounting plate, 102. 2020 aluminum profile, 103. 2040 aluminum profile, 2. sensing system, 201. transmitter mounting block, 202. transmitter, 203. camera, 204. receiver, 205. receiver mounting block, 3. actuator, 301. pneumatic gripper, 302. gripper mounting plate 302, 303. rotating mounting seat, 30301. first working surface, 30302. second working surface, 30303. third working surface, 304. A stopper, 305, an axial limit wire, 4, a driving mechanism, 401, a limit shaft, 40101, a fourth working surface, 402, a cylinder mounting plate, 403, a limit cylinder, 404, a rotating cylinder, 405, a second stopper, 40501, a fifth working surface, 406, a sleeve, 407, a first bearing, 408, an elastic retaining ring for the shaft, 409, a second bearing, 410, a double-sided driving shaft, 41001, a sixth working surface, 41002, a seventh working surface, 5, lettuce, 501, an abnormal leaf. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0030] like Figure 1 As shown, the end effector proposed in the present invention includes a frame 1, a sensing system 2, an actuator 3 and a driving mechanism 4; the sensing system 2 is installed in the frame 1 and the actuator 3, and is used to sense the hydroponic lettuce; the driving mechanism 4 is fixedly installed in the frame 1, and the driving mechanism 4 is connected to the actuator 3; the driving mechanism 4 drives the actuator 3 to achieve the removal of abnormal leaves of the hydroponic lettuce.

[0031] The frame 1 includes a robot arm mounting plate 101, a 2020 aluminum profile 102 and a 2040 aluminum profile 103; a plurality of 2020 aluminum profiles 102 and 2040 aluminum profiles 103 are connected to form a main frame, and the robot arm mounting plate 101 is fixedly mounted on the main frame for connecting to the end of the robot arm. When the camera 203 is placed horizontally, the centers of the transmitter 202 and the receiver 204 of the photoelectric switch are on the same vertical line as the center of the camera lens, and are collinear with the axis of the rotating shaft of the rotating cylinder 404.

[0032] The sensing system 2 includes a through-beam photoelectric switch and a camera 203. The through-beam photoelectric switch is mounted on the 2040 aluminum profile 103 at the bottom of the frame 1, and the camera 203 is mounted on the lower surface of the gripper mounting plate 302 of the actuator 3; wherein the through-beam photoelectric switch is used to detect the relative position between the end effector and the top of the target lettuce, and the camera 203 is used to detect the leaf state of the target lettuce. The through-beam photoelectric switch includes a transmitter mounting block 201, a transmitter 202, a receiver 204, and a receiver mounting block 205; the transmitter 202 is fixedly mounted on one side of the 2040 aluminum profile 103 at the bottom through the transmitter mounting block 201, and the receiver 204 is fixedly mounted on the other side of the 2040 aluminum profile 103 at the bottom through the receiver mounting block 205. Along the direction of the profile, the pneumatic gripper 301 of the actuator 3 is arranged between the transmitter 202 and the receiver 204, and in the initial state, the pneumatic gripper 301 gradually approaches the target lettuce during the falling process.

[0033] Since each lettuce does not grow exactly the same, and the contours of different sides of the same lettuce are also different, a driving mechanism that can adapt to the contour of the lettuce is needed. Figure 2 and Figure 3As shown, the driving mechanism 4 proposed by the present invention includes a limiting shaft 401, a cylinder mounting plate 402, a limiting cylinder 403, a rotating cylinder 404, a second stopper 405, a sleeve 406, a first bearing 407, an elastic retaining ring 408 for the shaft, an axial limiting steel wire 305, a second bearing 409, a rotating mounting seat 303 and a double-sided driving shaft 410; the cylinder mounting plate 402 is fixedly connected to the 2020 aluminum profile 102 on the side of the frame 1, the rotating cylinder 404 is fixedly installed in the cylinder mounting plate 402, and the cylinder mounting plate 402 on the upper side of the rotating cylinder 404 is fixedly installed A limit cylinder 403 is installed. The limit cylinder 403 and the rotating cylinder 404 are arranged at intervals up and down and their output shafts are facing the inside of the frame 1. The output shaft of the limit cylinder 403 is coaxially fixedly connected with the limit shaft 401. The end face of the limit shaft 401 is provided with an arc-shaped protrusion block. The fourth working surface 40101 of the arc-shaped protrusion block is used to cooperate with the first stop block 304 of the actuator 3 to realize the starting limit of the actuator 3; the limit shaft 401 is driven by the limit cylinder 403 and can realize 90-degree reciprocating rotation. The action execution of the actuator 3 is controlled by cooperating with the first stop block 304. A bearing mounting seat is fixedly installed at the end surface of the cylinder mounting plate 402 close to the inside of the frame 1, and the cylindrical end of the double-sided drive shaft 410 is installed in the bearing mounting seat through the second bearing 409, and the cylindrical end of the double-sided drive shaft 410 is coaxially fixedly connected with the output shaft of the rotating cylinder 404; wherein two first bearings 407 are provided, and a sleeve 406 is further provided between the two first bearings 407, and an annular groove is provided at the outer end surface of the bearing mounting seat close to the actuator 3, and an elastic retaining ring 408 for the shaft is embedded in the annular groove for limiting the first bearing 407 and the sleeve 406. The axial positioning of the rotating mounting seat 303 is achieved by six axial limiting steel wires 305 radially installed inside the rotating mounting seat 303. The rotating mounting seat 303 is installed outside the bearing mounting seat through the first bearing 407, and the claw mounting plate 302 of the actuator 3 is fixedly connected to the rotating mounting seat 303; an arc-shaped protrusion block is provided on the end face of the double-sided driving shaft 410 away from the rotating cylinder 404, and the inner hole of the rotating mounting seat 303 away from the rotating cylinder 404 is a special-shaped hole, which is formed by splicing a semicircular hole and a semi-elliptical hole, and the radius of the semicircular hole is larger than the short semi-axis of the semi-elliptical hole, and two step surfaces are formed between the semicircular hole and the semi-elliptical hole and are respectively recorded as the second working surface 30302 and the third working surface 30303, that is, the second working surface 30302 and the third working surface 30303, and the two working surfaces are coplanar. The arc-shaped protrusion block is arranged in the semicircular hole, the central angle of the arc-shaped protrusion block is less than 180 degrees, and the two sides of the arc-shaped protrusion block are respectively recorded as the sixth working surface 41001 and the seventh working surface 41002, and the two planes of the sixth working surface 41001 and the seventh working surface 41002 form an angle of 90°.A second stopper 405 is also installed on the side of the bottom of the cylinder mounting plate 402 away from the limiting cylinder 403. The fifth working surface 40501 of the second stopper 405 is used to cooperate with the first working surface 30301 of the rotating mounting seat 303 to achieve the rotation limit of the actuator 3. The fifth working surface 40501 of the second stopper 405 hinders the rotation of the actuator by contacting with the first working surface 30301 of the rotating mounting seat 303, and cooperates with the seventh working surface 41002 of the double-sided drive shaft 410 to limit the rotation of the actuator. The double-sided drive shaft 410 is driven by the rotating cylinder 404 and can achieve 180-degree reciprocating rotation. The action of the actuator 3 is executed by cooperating with the rotating mounting seat 303. Each time it rotates by its own weight, when the pneumatic gripper 301 contacts the abnormal lettuce leaves, the actuator automatically stops rotating, and the rotation is adaptive and easy to operate. The sixth working surface 41001 of the double-sided drive shaft 410 realizes the rotation of the actuator 3 by contacting the second working surface 30302 of the rotating mounting seat 303, thereby realizing the initialization of the end effector and the preparation action of discarding the blade. The seventh working surface 41002 of the double-sided drive shaft 410 realizes the rotation of the actuator 3 in the opposite direction by contacting the third working surface 30303 of the rotating mounting seat 303, thereby realizing the flipping action of the abnormal blade.

[0034] The actuator 3 includes a pneumatic gripper 301, a gripper mounting plate 302 and a first stopper 304; the gripper mounting plate 302 is fixedly connected to the rotating mounting seat 303 of the driving mechanism 4, the lower surface of the gripper mounting plate 302 is installed with the camera 203 of the sensing system 2, and the first stopper 304 is fixed to the side of the gripper mounting plate 302 close to the frame (i.e. close to the cylinder mounting plate 402), the first stopper 304 cooperates with the shaped protrusion block of the limiting shaft 401 of the driving mechanism 4 to realize the starting limit of the actuator 3; the pneumatic gripper 301 is also installed in the gripper mounting plate 302.

[0035] A plurality of mounting holes are provided in the gripper mounting plate 302 for adjusting the mounting position of the pneumatic gripper 301, thereby adjusting the height of the pneumatic gripper 301 to grasp the lettuce. The pneumatic gripper 301 opens and closes the gripper through positive and negative pressure to achieve flexible grasping of the leaves.

[0036] The working process of the end effector of the present invention is as follows:

[0037] like Figure 4As shown in (a), in the initial state, the double-sided drive shaft 410 has rotated clockwise to the bottom and the fifth working surface 41001 is in a horizontal state. Since the first stopper 304 of the actuator 3 is in contact with the fourth working surface 40101 of the limit shaft 401 in a vertical state, the actuator 3 is prevented from rotating by its own gravity. At this time, the working surface 41002 of the double-sided drive shaft 410 and the working surface 30303 of the rotating mounting seat are at a 90° angle. At the same time, the gripper mounting plate 302 is in a horizontal state, that is, the camera 203 is placed horizontally. The camera 203 in the horizontal state performs primary and secondary identification and positioning, and adjusts the position of the end effector so that the camera 203 is located directly above the lettuce plant and the pneumatic gripper is located above the petiole of the outermost abnormal leaf. Subsequently, the end effector moves vertically downward as a whole, and is positioned three times through the opposing photoelectric switch, that is, it reaches the working position. At this time, the top of the lettuce plant and the rotation center of the actuator 3 are located on the same horizontal plane. As shown Figure 4 As shown in (b), the limit shaft 401 rotates 90° counterclockwise, and the actuator 3 rotates a certain angle under its own gravity to approach the abnormal lettuce leaf, and performs the adaptive grasping preparation action of the abnormal leaf. When the pneumatic gripper 301 contacts the petiole of the abnormal leaf, the pneumatic gripper 301 works and clamps the petiole under the action of negative pressure. Figure 4 As shown in (c), the double-sided drive shaft 410 rotates 180° counterclockwise. During the rotation, the double-sided drive shaft first idles for a certain angle, and then the seventh working surface 41002 of the double-sided drive shaft 410 contacts the third working surface 30303 of the rotating mount 303. The actuator 3 passively rotates until the fifth working surface 40501 of the second stop block 405 contacts the first working surface 30301 of the rotating mount 303. At this time, the gripper mounting plate is in a vertical state. During the rotation, the abnormal leaves surround the lettuce stem and detach from the stem, completing the removal of the abnormal leaves. Then the limit shaft 410 rotates 90° clockwise to prepare for limiting the rotation of the actuator 3. Figure 4 As shown in (d), the end effector first moves to the top of the abnormal blade collection area, and the double-sided drive shaft 410 rotates 180° clockwise. During the rotation process, the double-sided drive shaft first idles 90°, and then the sixth working surface 41001 of the double-sided drive shaft 410 contacts the second working surface 30302 of the rotating mounting seat 303, and the actuator 3 passively rotates 90°. At this time, the fourth working surface 40101 of the limit shaft 401 contacts the first stopper 304, and the actuator 3 cannot rotate under its own gravity. Then the pneumatic gripper is released, the abnormal blade falls, and the discard is completed.

[0038] The present invention also proposes a method for removing abnormal leaves of hydroponic lettuce using an end effector, the method comprising the following steps:

[0039] Step 1: Install the end effector at the end of the robotic arm, use the camera 203 of the perception system 2 to collect images and perform image processing, and adjust the position of the end effector according to the image detection result until the end effector moves to the top of the target lettuce 5 with the center of the cross-section shape as the center of the lettuce; in the image processing, first identify whether the lettuce is inverted, and judge by whether there is a stem-like, approximately circular, cross-section in the image. If not, it means that the lettuce is not inverted and no operation is performed; if so, it means that the lettuce is inverted.

[0040] Step 2: Use the camera 203 of the perception system 2 to collect images again and perform image processing. If there is an abnormal leaf 501 in the target lettuce 5, execute step 3; otherwise, move the end effector to the next lettuce and execute step 1;

[0041] Step 3: Drive the robotic arm to move the end effector vertically downward as a whole and approach the target lettuce plant until the opposing photoelectric switch has a signal, indicating that the end effector has reached the top of the lettuce plant. The end effector stops moving downward and reaches the working position; control the limit cylinder 403 of the drive mechanism 4 to release the limit on the actuator 3, and the actuator 3 rotates downward by a certain angle until the pneumatic gripper 301 contacts the abnormal leaf. The pneumatic gripper 301 grabs the abnormal leaf again, and the drive mechanism 4 controls the actuator 3 to rotate upward in the opposite direction, so that the abnormal leaf is separated from the body of the target lettuce and the abnormal leaf is moved to the waste box; the drive mechanism 4 continues to control the actuator 3 to remove the abnormal leaf until all the abnormal leaves are removed.

[0042] Finally, it should be noted that the above embodiments and explanations are only used to illustrate the technical solution of the present invention rather than to limit it. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope disclosed in the technical solution of the present invention, which should be included in the scope of protection of the claims of the present invention.

Claims

1. An end effector for removing abnormal leaves of hydroponic lettuce, characterized in that: The invention comprises a frame (1), a sensing system (2), an actuator (3) and a driving mechanism (4); the sensing system (2) is installed in the frame (1) and the actuator (3) and is used to sense hydroponic lettuce; the driving mechanism (4) is fixedly installed in the frame (1); the actuator (3) is connected to the driving mechanism (4); and the driving mechanism (4) drives the actuator (3) to remove abnormal leaves of the hydroponic lettuce.

2. The end effector for removing abnormal leaves of hydroponic lettuce according to claim 1, characterized in that: The frame (1) comprises a mechanical arm mounting plate (101) and a profile; a plurality of profiles are connected to form a main frame, and the mechanical arm mounting plate (101) is fixedly mounted on the main frame.

3. The end effector for removing abnormal leaves of hydroponic lettuce according to claim 1, characterized in that: The sensing system (2) comprises a through-beam photoelectric switch and a camera (203), wherein the through-beam photoelectric switch is mounted at the bottom of the frame (1), and the camera (203) is mounted on the actuator (3); wherein the through-beam photoelectric switch is used to detect the relative position between the end actuator and the top of the target lettuce, and the camera (203) is used to detect the leaf state of the target lettuce.

4. The end effector for removing abnormal leaves of hydroponic lettuce according to claim 1, characterized in that: The driving mechanism (4) comprises a limiting shaft (401), a cylinder mounting plate (402), a limiting cylinder (403), a rotating cylinder (404), a second stopper (405), a first bearing (407), a second bearing (409), a rotating mounting seat (303) and a double-sided driving shaft (410); the cylinder mounting plate (402) is fixedly connected to the side of the frame (1), the rotating cylinder (404) is fixedly mounted in the cylinder mounting plate (402), and the limiting cylinder (403) is fixedly mounted in the cylinder mounting plate (402) above the rotating cylinder (404). ), the limit cylinder (403) and the rotating cylinder (404) are arranged at intervals in the upper and lower parts, and the output shafts of the two are directed toward the inside of the frame (1); the output shaft of the limit cylinder (403) is coaxially fixedly connected with the limit shaft (401); the end surface of the limit shaft (401) is provided with an arc-shaped protrusion block for cooperating with the actuator (3) to realize the start limit of the actuator (3); a bearing mounting seat is fixedly installed at the end surface of the cylinder mounting plate (402) close to the inside of the frame (1); the double-sided drive shaft (410) is installed in the bearing mounting seat through the second bearing (409) and the double-sided drive shaft (410) is fixedly ... The cylindrical end of the moving shaft (410) is coaxially fixedly connected to the output shaft of the rotating cylinder (404); the rotating mounting seat (303) is mounted outside the bearing mounting seat via a first bearing (407), and the actuator (3) is fixedly connected to the rotating mounting seat (303); an arc-shaped protrusion is provided on one end surface of the double-sided driving shaft (410) away from the rotating cylinder (404), and the inner hole of the end of the rotating mounting seat (303) away from the rotating cylinder (404) is a special-shaped hole, which is formed by splicing a semicircular hole and a semi-elliptical hole, and the radius of the semicircular hole is greater than the short semi-axis of the semi-elliptical hole, and the semicircular hole and Two step surfaces are formed between the semi-elliptical holes and are respectively recorded as the second working surface (30302) and the third working surface (30303). An arc-shaped protrusion block is arranged in the semi-circular hole. The central angle of the arc-shaped protrusion block is less than 180 degrees. The two side surfaces of the arc-shaped protrusion block are respectively recorded as the sixth working surface (41001) and the seventh working surface (41002). A second stopper (405) is also installed on the side of the bottom of the cylinder mounting plate (402) away from the limiting cylinder (403), which is used to cooperate with the rotating mounting seat (303) to realize the rotation limit of the actuator (3).

5. The end effector for removing abnormal leaves of hydroponic lettuce according to claim 1, characterized in that: The actuator (3) comprises a pneumatic gripper (301), a gripper mounting plate (302) and a first stopper (304); the gripper mounting plate (302) is fixedly connected to the driving mechanism (4); a sensing system (2) is installed on the lower surface of the gripper mounting plate (302); a first stopper (304) is fixed on a side of the gripper mounting plate (302) close to the frame; the first stopper (304) cooperates with the driving mechanism (4) to achieve the starting limit of the actuator (3); and a pneumatic gripper (301) is also installed in the gripper mounting plate (302).

6. The end effector for removing abnormal leaves of hydroponic lettuce according to claim 5, characterized in that: The gripper mounting plate (302) is provided with a plurality of mounting holes for adjusting the mounting position of the pneumatic gripper (301).

7. A method for removing abnormal leaves of hydroponic lettuce using the end effector of claim 1, characterized in that: The method comprises the following steps: Step 1: Install the end effector at the end of the robotic arm, use the camera (203) of the perception system (2) to collect images and perform image processing, and adjust the position of the end effector according to the image detection result until the end effector moves to the top of the target lettuce; Step 2: Use the camera (203) of the perception system (2) to collect images again and perform image processing. If there are abnormal leaves in the target lettuce, execute step 3; otherwise, move the end effector to the next lettuce and execute step 1; Step 3: drive the robot arm to move the end effector vertically downward and close to the target lettuce until the opposing photoelectric switch generates a signal; control the limit cylinder (403) of the drive mechanism (4) to release the limit on the actuator (3), so that the actuator (3) rotates downward, the actuator (3) contacts and grabs the abnormal leaf, and the drive mechanism (4) controls the actuator (3) to rotate upward in the opposite direction, so that the abnormal leaf is separated from the body of the target lettuce and is moved to a waste box; the drive mechanism (4) continues to control the actuator (3) to remove the abnormal leaf until all the abnormal leaves are removed.

8. A device, characterized in that: The device comprises the end effector of claim 1.

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