CN115943811A - End effector capable of picking automatically - Google Patents

Abstract

The invention discloses an end effector for autonomous picking, which comprises a claw shoulder part, an execution shell part, a claw finger part, a front connecting plate, an air flow auxiliary device, a camera part and a shearing part, wherein the claw shoulder part is connected with the execution shell part; the shell part comprises an execution shell and a back cover plate which are both in a cross structure, and the execution shell and the back cover plate are mutually embedded and form a sealed space in the middle. The invention provides an autonomous picking end effector with the functions of camera shooting assistance, pneumatic combination and automatic stretching, which effectively solves the problem of poor clamping caused by the growth states of different fruits by combining two modes of clamping and adsorption.

Description

End effector capable of automatically picking

Technical Field

The invention relates to the field of crop picking equipment, in particular to an end effector for autonomous picking.

Background

Crop picking typically requires a significant amount of labor to ensure the integrity and maturity of the picked crop. However, the efficiency of manual picking is not high, the labor intensity is high, the planting cost is undoubtedly increased for large farms, and therefore the picking type machine needs to be researched and developed vigorously.

At present, a main picking machine consists of a visual imaging device, a mechanical arm, a movable chassis and an end effector. The end effector has two kinds of clamping by a mechanical arm and adsorbing by a vacuum chuck, and in addition, the broken stem connected with crops has three methods of laser sintering, mechanical twist-off and sharp blade cutting.

However, because the growth states of various crops are different, some crops grow in strings, and some single crops easily cause fruit damage, clamping failure and the like in the picking process of an end effector of the machine. Therefore, the end effector with camera assistance, pneumatic combination and automatic stretching needs to be developed in a targeted manner, and a new idea is provided for crop picking.

Disclosure of Invention

The purpose of the invention is as follows: aiming at the defects of the prior art, the invention provides the end effector which is assisted by camera shooting, is combined pneumatically and is automatically telescopic and used for picking automatically, and the problem of poor clamping caused by the growth states of different fruits is effectively solved by combining two modes of clamping and adsorption.

The technical scheme is as follows: the invention discloses an end effector for autonomous picking, which is characterized in that: comprises a claw shoulder part, an execution shell part, a claw finger part, a front connecting plate, an airflow auxiliary device, a camera part and a shearing part; the shell part comprises an execution shell and a back cover plate which are both of cross structures, and the execution shell and the back cover plate are mutually embedded and form a sealed space in the middle.

The first motor is positioned in the center of the execution shell, and the output end of the motor faces to a target direction; the first screw rod is connected with a first motor through a coupler; the fixed ends of the first telescopic rods are respectively installed on two sides of the peripheral extending part of the execution shell.

The back cover plate is provided with a second motor, a bevel gear, a second screw rod and a gear box; the gear box is fixed in the center of the back cover plate, the bottom surface of the gear box is connected with the back cover plate, and bevel gears are arranged on the other surfaces of the gear box; the bevel gear is composed of 5 straight bevel gears, the tops of the 5 straight bevel gears are overlapped, the axes of the 5 straight bevel gears are vertical, and the center of each straight bevel gear is connected with the second screw rod.

One end of the claw shoulder part close to the execution shell part is of an open structure, and the other end of the claw shoulder part is of a closed structure and is folded by 90 degrees; and a capping nut is arranged at the end part of the first screw rod.

The two sides of the inside of the claw shoulder part are provided with telescopic ends of a first telescopic rod, and the outside of the claw shoulder part is provided with a second screw rod nut, a screw rod nut connecting block, a sliding block and a guide rail; the sliding block is fixedly connected to the claw shoulder part and wraps the guide rail in the claw shoulder part, and the outer part of the sliding block is connected with the second screw nut through the screw nut connecting block; one end of the guide rail is fixed on the execution shell, and the other end of the guide rail is positioned by the sliding block.

The front connecting plate is provided with a first screw rod nut, a second telescopic rod and a camera shooting part, is of a cross structure, is provided with a through hole in the center and is provided with hinge holes at four ends; the first lead screw nut is installed in the center of the front connecting plate, the fixed end of the second telescopic rod is installed in hinge holes at four ends of the front connecting plate, and the camera shooting part is installed above the front face of the front connecting plate.

The finger part comprises a knuckle metal rod I, a knuckle metal rod II, a fingertip and a flexible air bag; the two ends of the first knuckle metal rod and the two ends of the second knuckle metal rod are respectively connected with a claw shoulder part and a fingertip, and the middle of the metal rods is connected with the front connecting plate through a second telescopic rod; the inner side of the tail end of each fingertip is provided with a flexible air bag, the 2 metal rods are arranged in parallel, and a claw shoulder part, a second telescopic rod and the fingertips are arranged among the metal rods in a clearance mode.

The air flow auxiliary device comprises an air pump, an air flow ring and an air pipe; the air flow ring is positioned in the center of the end effector and is connected with the air pump through 4 air pipes; the trachea is a hard tube, and the joint of the trachea and the air pump is a hose.

The shearing part comprises a blade, a fourth telescopic rod and a third telescopic rod, wherein 2 telescopic rods are vertically arranged; one end of the third telescopic rod is fixed on the execution shell, and the other end of the third telescopic rod is a telescopic end connected with the fourth telescopic rod; the blade is detachable structure, is fixed in the flexible end port of fourth telescopic link.

Wherein, the telescopic link includes dead lever and extension rod, and both connect on different parts, and the dead lever is inside to be equipped with spacing recess, reaches spacing recess position when the extension rod, no longer stretches out and draws back.

Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: the fruit picking device effectively solves the problem of poor clamping caused by the growth states of different fruits by combining the clamping and the adsorption modes, and the application of the air flow device enables the bunched fruits to be independent, thereby avoiding the problem of clamping a plurality of fruits in the picking process. Utilize camera assistance-localization real-time discernment fruit in addition for it is more accurate to snatch, and the clamping jaw can adapt to the fruit of equidimension not. The end of the fingertip is provided with a flexible air bag, and due to the irregular shape of the fruit, the fruit may not be completely fixed in the clamping jaw after the clamping jaw is folded, and the fruit can be clamped more firmly without damaging the integrity of the fruit through the flexible air bag. Finally, the stem connected with the fruit is cut off by utilizing the cutting part, and compared with a rotary twisting and picking mode, the internal structure of the soft fruit cannot be damaged.

Drawings

FIG. 1 is a schematic structural diagram 1 of the present invention;

FIG. 2 is a schematic structural diagram of the present invention 2;

FIG. 3 is a schematic front view of the present invention;

FIG. 4 is a schematic view of a half-section of the present invention;

FIG. 5 is a schematic cross-sectional view of the gas flow ring of the present invention;

FIG. 6 is a schematic structural diagram of an actuator housing of the present invention 1;

FIG. 7 is a schematic structural diagram of an actuator housing of the present invention, FIG. 2;

FIG. 8 is a schematic view of the back cover plate of the present invention 1;

FIG. 9 is a schematic structural view of a back cover plate of the present invention, FIG. 2;

in the figure 1, a claw shoulder part; 1001 is a first telescopic rod; 1002 is a first motor; 1003 is a coupling; 1004 is a first lead screw; 1005 is a capping nut; 2 is an execution shell part; 2001 is the actuator housing; 2002 is a back cover plate; 2003, a second motor; 2004 is a bevel gear; 2005 is the second lead screw; 2006 is a second feed screw nut; 2007 is a screw nut connecting block; 2008 is a slide block; 2009 a guide rail; 2010 is a gear box; 3 is a claw finger part; 3001 is a knuckle metal rod I; 3002 is a second knuckle metal rod; 3003 is a fingertip; 3004 a flexible air bag; 4 is a front connecting plate; 4001 is a first screw nut; 4002 is a second telescopic rod; 5 is an airflow auxiliary device; 5001 is an air pump; 5002 is an air flow ring; 5003 is trachea; 50021 is an annular deflecting groove; 50022 is a soft contact body; 6 is a camera part; 7 is a shearing part; 7001 is a blade; 7002 is a fourth telescopic rod; 7003 is the third telescopic rod.

Detailed Description

The technical solution of the present invention is further described with reference to the accompanying drawings and the detailed description.

The inventive end effector for autonomous picking comprises an actuator housing part 2, connected to a robot arm, for holding the end effector and for mounting parts of the respective parts. The claw shoulder part 1 and the four symmetrical claw shoulders are connected with the execution shell part 2 through telescopic rods and are used for adapting to the size of the grabbed crops and adjusting the grabbing range. The claw finger parts 3 are respectively connected with the claw shoulders through hinges and are used for executing grabbing actions. And the front connecting plate 4 is connected with the claw finger parts 3 through four telescopic rods and used for fixing the camera shooting part 6 and the airflow auxiliary device 5 and controlling the claw finger parts to be folded. The air flow auxiliary device 5 is connected with an air pump 5001 arranged inside the execution shell 2001 through a front connecting plate 4 by four air pipes 5003 and is used for absorbing fruits. And the camera part 6 is arranged on the front connecting plate 4 and is used for determining the position of the fruit. A cutting part 7 installed at the actuator case 2001 for cutting a stem connected to the fruit.

The housing portion 2 includes an actuator housing 2001 and a back cover plate 2002 each having a cross-shaped configuration, and the actuator housing 2001 and the back cover plate 2002 are fitted to each other and form a sealed space in the middle. The executing housing 2001 is provided therein with a first telescopic rod 1001, a first motor 1002, a first screw 1004, and an air pump 5001, and four sides of the inside are respectively provided with two telescopic rods. One end of the claw shoulder part 1 close to the execution shell part 2 is of an open structure, the other end of the claw shoulder part is of a closed structure, and a small section extends out after being folded by 90 degrees. The open end of the claw-shoulder part 1 is in a cuboid shape, and first telescopic rods 1001 are symmetrically arranged on two sides of the inside of the claw-shoulder part. And a screw rod nut and guide rail sliding block structure is arranged on the rear side outside the claw shoulder, and the claw shoulder part is adjusted to stretch by a second motor 2003. The telescopic link includes mobile jib and time pole, and the mobile jib is fixed in carrying out casing 2001, and the time pole is fixed inside the claw shoulder, and the mobile jib is inside to have spacing recess, reaches spacing recess position when the time pole, no longer stretches out and draws back. The front connecting plate 4 is in a cross shape, a screw rod nut is installed at the center of the front connecting plate, four sides of the front connecting plate are connected with the claw fingers through second telescopic rods 4002, and meanwhile the center of the front connecting plate is connected with four air pipes.

In use, as shown in fig. 1-9, the end effector for autonomous picking comprises a claw shoulder part 1, an execution shell part 2, a claw finger part 3, a front connecting plate 4, an air flow auxiliary device 5, a camera part 6 and a shearing part 7; the prior art discloses a plurality of technologies related to the shooting of crop fruits, and adopts the prior art scheme.

The actuator housing part 2 comprises an actuator housing 2001 which does not move relative to each other during the gripping process and which is connected at its rear end to a robot arm for fixing various parts. A back cover plate 2002, a back cover of the actuator casing, seals the inside of the actuator casing, preventing branches and leaves from entering the actuator casing when the claw shoulders are opened. And a second motor 2003 installed at the outside of the gear box for driving the driving gear to move. And the bevel gears 2004 are meshed with each other for driving the screw rod to rotate. The second lead screw 2005, which is four in number, passes through the bevel gear and drives the claw shoulder to move in cooperation with the lead screw nut. And the second screw rod nut 2006 is matched with the second screw rod to drive the claw shoulder to move. And a feed screw nut connecting block 2007 which connects the feed screw nut and the slider. Slider 2008, guide rail 2009, the inside parcel guide rail of slider is fixed in claw shoulder back, and guide rail one end is fixed in and is executed the casing, and the other end extends to the claw shoulder, and both cooperations make the claw shoulder motion more smooth and easy. The gear box 2010 is used to fix the gears and the motor.

The working mode of the components is as follows: first, the size of the crop is recognized by the image pickup part 6, the movement range of the claw shoulder part 1 is calculated, the first motor 1002 drives the bevel gear set 2004 to rotate, the second lead screw 2005 rotates to move the second lead screw nut 2006, the slide block 2008 connected with the second lead screw nut 2006 through the lead screw nut connecting block 2007 moves along the guide rail, and the slide block 2008 is fixed with the claw shoulder part 1, so that the claw shoulder part 1 moves relative to the execution shell part 2 until the inner part of the claw has a sufficient size. Note that when the jaw shoulder portion 1 moves relative to the actuating housing portion 2, the first telescopic rod 1001 inside the jaw shoulder portion 1 for maintaining structural stability also lengthens and shortens with the aid of the jaw shoulder portion 1. The second telescopic rod 4002, which is also used to control the closing of the fingers, is also elongated because the jaw shoulder portion 1 is away from the implement housing portion 2, but when the jaw shoulder stops moving, the length of the second telescopic rod 4002 no longer changes.

The finger part 3 comprises a knuckle metal rod one 3001, a knuckle metal rod two 3002, a fingertip 3003 and a flexible air bag 3004. The knuckle metal rod I3001 and the knuckle metal rod II 3002 are identical in size and length and are arranged above and below the hinge hole of the claw shoulder part 1 in parallel. The middle point of the metal rod is provided with the extension end of a second telescopic rod 4002. The other end of the metal rod is provided with a fingertip 3003 in parallel with the gap, and the inner side of the tail end of the fingertip is provided with a flexible air bag 3004. The actuator casing 2001 is internally provided with a first motor 1002, and two ends of a coupling 1003 are respectively coupled with a motor output shaft and a first screw rod 1004. The end of the screw is fitted with a capping nut 1005. The front connecting plate 4 is cross-shaped, and four sides are connected with four second telescopic rods 4002. The center is provided with a hole, and a screw rod nut is embedded in the hole.

The part of working principles are as follows: when the position of the jaw shoulder portion 1 is determined, the length of the second telescopic bar 4002 is not changed any more, and the jaw fingers start to bend inward. The first motor 1002 rotates in conjunction with the first lead screw 1004. The front connecting plate 4 is driven by the lead screw nut to move inwards along the axial direction of the first lead screw 1004. Meanwhile, one end of the second telescopic rod 4002 located around the front connecting plate 4 is retracted backwards, and the total length of the second telescopic rod 4002 is unchanged, so that the other end of the jaw joint metal rod is pulled to retract inwards. And (3) until the first screw rod nut 4001 moves to the bottom of the second screw rod, the claw tips are folded to a point, the flexible air bags 3004 of the finger tips 3003 start to be inflated at the same time, the pressure sensors with the air bags reach preset values, and the inflation is stopped.

Description of the flexible bladder: when the fruit is wrapped by the four fingers, the fruit is completely fixed by the flexible air bag because the fruit is irregular in shape or the wrapping space inside the paw is slightly larger than the volume of the fruit, a gap possibly exists in a certain direction in the four-paw direction, and the fruit can still move in a small range like being covered by the cage. The flexible air bags and the pressure sensors on the surfaces of the air bags can protect fruits from being damaged by machinery in the picking process, and consumption in the picking process is reduced.

The airflow assisting device 5 includes an air pump 5001, an airflow ring 5002, and an air pipe 5003. The air pump 5001 is located inside the actuator housing portion 2, and sucks air in an annular area near the air flow ring 5002 through four air pipes 5003. Four air pipes 5003 are hard air pipes which penetrate through the holes of the front connecting plate 4 and are connected with the hollow part of the airflow ring 5002. Note that the air tube 5003 is longer than the front web 4 by the greatest distance of movement, and the air flow ring 5002 is always located in front of the front web.

The specific working principle of the airflow auxiliary device 4 is as follows: firstly, the position of a target fruit is determined by utilizing an identification technology, the pose of the end effector is adjusted by the mechanical arm, the end effector is enabled to be slowly close to the fruit, and the center of the end effector is enabled to be aligned to the fruit. The air pump 5001 generates suction which is transmitted to the air flow ring 5002 through an air pipe 5003 to separate the target fruit from nearby branches, leaves and fruits and to close the grabbing range of the end effector.

As explained in relation to the airflow assisting device 4, the airflow assisting device 4 is intended to suck the fruit into the gripping range. The advantage of using air flow is that the air flow is a flexible force, does not actually contact the fruit, and does not damage the fruit and separate the target fruit from other branches and leaves. The airflow ring 5002 is internally provided with an annular diversion groove 50021, as shown in the drawing, the airflow inlet part is the inner ring position of the airflow ring 5002, firstly, in this way, a certain area with concentrated inlet ports can be enabled, an overlarge airflow ring can not be formed around the airflow ring, in addition, the air inlet can be blocked due to the direct adsorption of the range on the air inlet, the wind power generation assembly can be damaged, and the suction force is continuously overlarge, tomatoes can be crushed, and through this way, the tomatoes can be contacted with the edge position of the inner ring, as shown in the drawing, and the contact position is also provided with a soft contact body 50022, a sponge material can be adopted, and as crops belong to an irregular body, the notch of the annular diversion groove 50021 can not be blocked when the crops are contacted with the airflow ring 5002, so that the problems that the airflow does not circulate, the motor part of the air pump is burned out, in addition, the suction force is not overlarge, the tomatoes are deformed and the like can not occur.

The picking section 7 includes a blade 7001, a third telescopic bar 7003, and a fourth telescopic bar 7002. The third extension bar 7003 and the fourth extension bar 7002 are perpendicular to each other, one end of the third extension bar 7003 is fixed to the actuator housing part 2, and the fourth extension bar 7002 is fixed to the extension end. The blade 7001 is fixed at the port of the fourth telescopic end and is detachable.

The working principle of the part is as follows: when grasping is completed, the picking device learns the degree of bending of the four fingers, determines the extension distance of the third extension bar 7003 and the fourth extension bar 7002, and rotates the blade 7001 to cut the stem connected to the fruit.

The whole implementation process of the invention is as follows:

first, the initialization state of the end effector is guaranteed: the claw shoulder part 1 is folded without a gap with the execution shell part 2, the front connecting plate 4 is positioned at the maximum position, the end effector paw is opened, and all the telescopic rods are in the shortest state. When the camera catches the target, the arm drives end effector and slowly approaches. When the camera 6 of the end effector catches the target, the airflow auxiliary device 5 generates suction force to suck the target into the grabbing range. At the same time, the gripper shoulder section 1 is moved away from the actuator housing section 2, so that the gripping range of the end effector is adapted to the fruit size. The first extension rod 1001 and the second extension rod 4002 extend correspondingly, and after the claw shoulders stop moving, the first extension rod and the second extension rod stop extending and contracting, and the length is kept unchanged. The front web 4 then moves rearwardly, bringing the finger portions 3 together. After the fingertip 3003 is closed to a point, the flexible air bag 3004 at the end of the fingertip is inflated to firmly fix the gripped crop in the end effector. And finally, cutting off stems connected with the fruits by using a shearing device to finish the picking of the fruits. After the fruit is placed in the collection box, the end effector returns to the initial state.

The fruit picking device effectively solves the problem of poor picking caused by the growth states of different fruits by combining the two modes of clamping and adsorption, and the application of the air flow device enables bunched fruits to be independent, thereby avoiding the problem of picking a plurality of fruits in the picking process. Utilize camera assistance-localization real-time discernment fruit in addition for it is more accurate to snatch, and the clamping jaw can adapt to the fruit of equidimension not. The end of the fingertip is provided with a flexible air bag, and due to the irregular shape of the fruit, the fruit may not be completely fixed in the clamping jaw after the clamping jaw is folded, and the fruit can be clamped more firmly without damaging the integrity of the fruit through the flexible air bag. Finally, the stem connected with the fruit is cut off by utilizing the cutting part, and compared with a rotary twisting and picking mode, the internal structure of the soft fruit cannot be damaged.

Claims (10)

1. An end effector for autonomous picking, comprising: the device comprises a claw shoulder part (1), an execution shell part (2), a claw finger part (3), a front connecting plate (4), an airflow auxiliary device (5), a camera part (6) and a shearing part (7); the shell part (2) comprises an execution shell (2001) and a back cover plate (2002) which are both in a cross-shaped structure, wherein the execution shell (2001) and the back cover plate (2002) are mutually embedded and form a sealed space in the middle.

2. The autonomous picking end effector of claim 1, wherein: a first telescopic rod (1001), a first motor (1002), a first screw rod (1004) and an air pump (5001) are arranged in the execution shell (2001), the first motor (1002) is positioned in the center of the execution shell (2001), and the output end of the motor faces to a target direction; the first screw rod (1004) is connected with a first motor (1002) through a coupling (1003); the fixed ends of the first telescopic rods (1001) are respectively arranged on two sides of the peripheral extending part of the execution shell (2001).

3. The autonomous picking end effector of claim 1, wherein: the back cover plate (2002) is provided with a second motor (2003), a bevel gear (2004), a second screw rod (2005) and a gear box (2010); the gear box (2010) is fixed at the center of the back cover plate (2002), the bottom surface of the gear box is connected with the back cover plate (2002), and bevel gears (2004) are arranged on the other surfaces of the gear box; the bevel gear (2004) is composed of 5 straight bevel gears, the tops of the 5 straight bevel gears are overlapped, the axes of the 5 straight bevel gears are vertical, and the center of each straight bevel gear is connected with the second screw rod (2005).

4. The autonomous picking end effector of claim 2, wherein: one end of the claw shoulder part (1) close to the execution shell part (2) is of an open structure, and the other end of the claw shoulder part is of a closed structure and is folded by 90 degrees; and a capping nut (1005) is arranged at the end part of the first screw rod (1004).

5. The autonomous picked end effector of claim 4, wherein: the two sides in the claw shoulder part (1) are provided with telescopic ends of a first telescopic rod (1001), and the outside is provided with a second screw nut (2006), a screw nut connecting block (2007), a sliding block (2008) and a guide rail (2009); the sliding block (2008) is fixedly connected to the claw shoulder part (1) and wraps the guide rail (2009) in the sliding block, and the outside of the sliding block (2008) is connected with a second screw nut (2006) through a screw nut connecting block (2007); one end of the guide rail (2009) is fixed on the execution shell (2001), and the other end of the guide rail is positioned by the sliding block (2008).

6. The autonomous picking end effector of claim 1, wherein: the front connecting plate (4) is provided with a first screw rod nut (4001), a second telescopic rod (4002) and a camera shooting part (6), the front connecting plate (4) is of a cross structure, a through hole is formed in the center of the front connecting plate, and hinge holes are formed in four ends of the front connecting plate; the first feed screw nut (4001) is installed at the center of the front connecting plate (4), the fixed end of the second telescopic rod (4002) is installed in hinge holes at four ends of the front connecting plate (4), and the camera shooting part (6) is installed above the front face of the front connecting plate (4).

7. The autonomous picking end effector of claim 1, wherein: the claw-finger part (3) comprises a knuckle metal rod I (3001), a knuckle metal rod II (3002), a fingertip (3003) and a flexible air bag (3004); the two ends of the first knuckle metal rod (3001) and the two ends of the second knuckle metal rod (3002) are respectively connected with a claw shoulder part (1) and a fingertip (3003), and the middle of each metal rod is connected with a front connecting plate (4) through a second telescopic rod (4002); fingertip (3003) end inboard is equipped with flexible gasbag (3004), 2 individual metal pole parallel arrangement, and claw shoulder portion (1), second telescopic link (4002) and fingertip (3003) are installed to the clearance between the metal pole.

8. The autonomous picking end effector of claim 1, wherein: the air flow auxiliary device (5) comprises an air pump (5001), an air flow ring (5002) and an air pipe (5003); the air flow ring (5002) is positioned in the center of the end effector and is connected with the air pump (5001) through 4 air pipes (5003); the air pipe (5003) is a hard pipe, and a hose is arranged at the joint of the air pipe (5003) and the air pump (5001).

9. The autonomous picking end effector of claim 1, wherein: the shearing part (7) comprises a blade (7001), a fourth telescopic rod (7002) and a third telescopic rod (7003), and 2 telescopic rods are vertically arranged; one end of the third telescopic rod (7003) is fixed to the execution shell (2001), and the other end of the third telescopic rod is a telescopic end which is connected with the fourth telescopic rod (7002); the blade (7001) is of a detachable structure and is fixed at the port of the telescopic end of the fourth telescopic rod (7002).

10. The autonomous picking end effector of any of claims 2, 4, 5, 6, 7, 9, wherein: the telescopic link includes dead lever and extension rod, and both connect on the part of difference, and the dead lever is inside to be equipped with spacing recess, reaches spacing recess position when the extension rod, no longer stretches out and draws back.

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