An end-effector for fruit picking with wrist joint and rotatable broken handle function

Abstract

The present invention relates to an agricultural and forestry picking machine. The purpose is to provide a fruit picking end gripper with a wrist joint and a rotating handle-breaking function, and this manipulator should have the characteristics of being structurally compact, light in weight, and highly reliable. The technical solution is a fruit picking end gripper with a wrist joint and a rotating handle-breaking function, which is characterized in that: this fruit picking end gripper further includes an opening and closing drive assembly for driving the hand claws, a swing drive assembly connected to the hand claws through a wrist joint, and a rotating mechanism for driving the swing drive assembly to rotate.

Description

Technical Field

[0001] The invention relates to an agricultural and forestry picking machine, in particular to a fruit picking terminal gripper with a wrist joint and a rotating handle breaking function. Background Art

[0002] At present, the fruit picking operation is mainly manual, and the degree of automation is low. Most of the existing related picking robots use adsorption or drag-type handle breaking; for example, CN114161436A discloses a mechanical gripper for non-destructive fruit picking, whose structure includes a gripper and a gripper; wherein the gripper includes a fixed rod and a rotating rod, the rotating rod is nested inside the fixed rod, and the first motor on the fixed rod controls the rotation of the rotating rod; a sliding rod is nested in the rotating rod, and a first fixed seat with a gripper is installed at the end of the sliding rod; the gripper includes a plurality of finger grippers rotatably connected to the first fixed seat; a sliding rail and a second motor for controlling the sliding rod to move along the sliding rail are provided in the rotating rod; a second fixed seat with a plurality of connecting rods is installed at the end of the rotating rod away from the fixed rod, and the two ends of the connecting rod are respectively hinged to the finger gripper and the second fixed seat. The mechanical gripper has insufficient degrees of freedom and cannot cope with the complex and diverse fruit growth postures, and it is easy to damage the fruit if the fruit is separated from the tree by pulling alone. Therefore, it is of great significance to develop a fruit picking end gripper with a wrist joint and a rotating handle breaking function. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the above-mentioned background technology and provide a fruit picking end gripper with a wrist joint and a rotating handle breaking function. The manipulator should have the characteristics of compact structure, light weight and high reliability.

[0004] The technical solution provided by the present invention is:

[0005] A fruit picking end gripper with a wrist joint and a rotating handle breaking function, comprising a hand claw capable of holding round fruits; characterized in that: the fruit picking end gripper also comprises an opening and closing driving component for driving the hand claw, a swing driving component connected to the hand claw through a wrist joint, and a rotating mechanism for driving the swing driving component to rotate;

[0006] The gripper includes a plurality of fingers which are radially arranged on the gripper base and can swing toward the axis direction of the gripper base; the opening and closing drive assembly includes a finger motor which is fixed on the gripper base and drives the plurality of fingers simultaneously through a first drive rope; the wrist joint includes a joint ball and a joint socket which cooperate with each other, and a universal joint connecting the gripper base is installed in the hollow part of the joint ball and the joint socket; the swing drive assembly includes a plurality of second drive ropes which are respectively connected to the wrist joint and an electric push rod which drives the gripper base through a gear rack structure which is connected to the plurality of second drive ropes; the rotating mechanism includes a rotating motor which drives the universal joint to rotate.

[0007] The fingers are in an arc shape; each finger is hinged on the gripper base and swings in the direction of the gripper base axis, and the outer side of the finger has the potential energy to fold outward due to the force of a spring; the first drive rope connects the fingers and applies a torque to them to swing toward the same center.

[0008] The finger motor is installed in a blind hole in the middle of the gripper base, and a reel for pulling the first driving rope is installed on the motor shaft of the finger motor.

[0009] One end of the joint ball has a handle rod extending outward to connect to a rope-threading adjustment piece, and the joint ball has an inner cavity coaxially arranged with the handle rod and passing through the joint ball; one end of the joint socket is equipped with a connecting rod extending outward to connect to a disc; the connecting rod has through holes coaxially arranged with the connecting rod and passing through both ends of the connecting rod; a joint socket flange mounted on the outside of the joint ball and having a lubricating oil nozzle is also connected to the joint socket by a plurality of bolts.

[0010] The universal joint is installed in the inner cavity of the joint ball; one end of the universal joint is rotatably positioned in the inner cavity of the handle rod through a bearing and fixed to the gripper base, and the other end is rotatably positioned in the through hole of the connecting rod through a bearing and connected to the output shaft of the rotating motor.

[0011] The rope threading adjusting member, the joint flange and the periphery of the disc are respectively provided with a plurality of rope holes, and the plurality of rope holes on each member are located on the same circumference; each second driving rope connected to the rope threading adjusting member sequentially passes through the rope hole on the joint flange and the rope hole on the disc and then extends into the transmission housing.

[0012] The transmission housing is provided with an upper inner cavity for installing the rotating motor and a lower inner cavity for installing the gear rack structure.

[0013] Two pairs of racks that can slide along the length direction are positioned in the lower inner cavity through a bracket; the tooth surfaces of the two racks in each pair of racks face each other and are simultaneously meshed with a gear positioned on the frame, the same end of the two racks is respectively connected to two second driving ropes, and an electric push rod drives the other end of one of the racks.

[0014] The axes of the two gears matched with the two pairs of racks are perpendicular to each other and perpendicular to the length direction of the transmission housing.

[0015] The beneficial effects of the present invention are as follows: the provided fruit picking end gripper adopts a universal joint driven by a rotating motor and is arranged at a wrist joint, and is combined with a rope drive structure driven by a finger motor and a rope drive structure driven by an electric push rod. It not only has multiple degrees of freedom so that the entire manipulator has various picking postures that simulate human hands, but also has dexterous movements, compact and lean structure, light weight, high working reliability, and is suitable for the picking needs of various round fruits. Brief Description of the Drawings

[0016] Figure 1 It is a schematic three-dimensional structure diagram of an embodiment of the present invention.

[0017] Figure 2 It is Figure 1 a schematic three-dimensional structure diagram of the gripper part in

[0018] Figure 3 It is Figure 2 a schematic cross-sectional structure diagram of

[0019] Figure 4 It is Figure 1 a schematic three-dimensional structure diagram of the wrist joint part in

[0020] Figure 5 It is Figure 4 a schematic three-dimensional structure diagram of the joint sphere in

[0021] Figure 6 It is Figure 4 a schematic three-dimensional structure diagram of the joint socket in

[0022] Figure 7 It is Figure 4 a schematic three-dimensional structure diagram of the joint socket flange in

[0023] Figure 8 It is Figure 1 a schematic installation structure diagram of the universal joint in the wrist joint part in

[0024] Figure 9 It is a schematic diagram of the connection relationship between the rotary motor and the universal joint in the swing drive assembly.

[0025] Figure 10 It is a schematic diagram of the cooperation relationship between the gear, the rack and the electric push rod in the swing drive assembly.

[0026] Figure 11 It is Figure 10 a schematic installation structure diagram of the described gear, rack and electric push rod in the transmission housing.

[0027] Reference numerals in the figure:

[0028] 1. Finger; 2. Spring; 3. Second drive rope; 4. Transmission housing; 5. Joint socket; 5.1. Joint socket flange; 5.2. Connecting rod; 6. Joint sphere; 6.1. Shank; 7. Gripper base; 7.1. Finger motor; 8. Connection end; 9. First drive rope; 9.1. Combined drive rope; 10. Rope threading adjusting part; 11. Lubricating nozzle; 12. Disc; 13. Rack; 14. Gear; 15. Electric push rod; 16. Rolling bearing; 17. First shaft; 18. Universal joint; 19. Second shaft; 20. Coupling; 21. Rotary motor. Detailed implementation mode

[0029] The following is further described in conjunction with the embodiments shown in the accompanying drawings.

[0030] The fruit-picking end gripper with a wrist joint and a rotatable broken handle function shown in the accompanying drawings includes a claw that can hold a round fruit; this is similar to the existing fruit-picking claws.

[0031] The fruit-picking end gripper of the present invention further includes an opening and closing drive assembly for driving the claw, a swing drive assembly connected to the claw through a wrist joint, and a rotation mechanism for driving the swing drive assembly to rotate.

[0032] Figure 2 The shown claw includes several arc-shaped fingers (preferably three fingers), which can better envelope the round fruit. These fingers are radially arranged on the gripper base, and one end of each finger is hinged to the gripper base through a horizontally arranged hinge shaft, so that these fingers can swing in the axial direction of the gripper base; the outer side of each finger is connected to the gripper base 7 through a spring 2 (the two ends of the spring are respectively hooked to the pull rings fixed on the periphery of the gripper base and the pull rings fixed on the outer side of the finger), so as to have the potential energy to fold outwards under the force of the spring. The hinged end of each finger is connected (the rope is fixed by the clamping screw 1-1 on the finger, which is convenient for adjusting the tightness of the rope) to the first drive rope 3, and after the rope is tightened in the inner diameter direction, it is knotted and fixed to the first drive ropes on the other fingers, and then the combined drive rope 9.1 connected to the knotted end extends downwards to receive the pulling force of the finger motor. From Figure 2 、 Figure 3 It can be seen that: in the axial direction of the gripper base, the connection point of each finger connecting the first drive rope has a distance from the active axis of the finger. When the first drive rope is pulled, a rotational torque is formed for each finger to swing in the axial direction of the gripper base; since the first drive rope applies force to these fingers at the same time, these fingers swing towards the same center at the same time, forming an operation action of grasping the round fruit. The fingers are also covered with a flexible material to avoid damaging the fruit during the picking operation.

[0033] The opening and closing drive assembly includes a finger motor 7.1 that drives the several fingers through the first drive rope at the same time; a blind hole is opened in the middle of the gripper base (the opening of the blind hole faces the fingers), a finger motor is installed in the blind hole, a reel is installed on the motor shaft of the finger motor, and the combined drive rope is wound and tightened on the reel; when the finger motor rotates forward, it can drive each finger to perform the operation of grasping the fruit through the combined drive rope and the first drive rope in turn. When the finger motor rotates in reverse (loosening the rope), the potential energy of the spring can be used to open each finger to perform the operation of releasing the fruit.

[0034] The wrist joint includes a mutually cooperating joint sphere 6 and joint socket 5 (see Figures 4 to 7 ); in addition, a joint socket flange 5.1 sleeved outside the joint sphere is integrally connected to the joint socket by a number of bolts, so that the joint sphere 6 and the joint socket form a rotatable ball joint and the two cannot be separated; a lubricating nozzle 11 is installed on the joint socket flange for adding lubricating oil; a number of bolt holes and a number of rope holes for guiding the insertion of the driving rope are made on the periphery of the joint socket flange. One end of the joint sphere has a shank 6.1 extending outwards for connecting the rope threading adjusting member 10; a cavity coaxial with the shank and passing through the joint sphere is made inside the joint sphere (both this cavity and the perforation of the connecting rod are hollow parts), and the inner cavity space is larger than the outer contour of the universal joint to avoid interference with the universal joint during movement. One end of the joint socket is equipped with a connecting rod 5.2 extending outwards for connecting the disc 12; a perforation coaxial with the connecting rod and passing through both ends of the connecting rod is made in the connecting rod.

[0035] The universal joint is installed in the inner cavity of the joint sphere (see Figure 8 ); the first shaft 17 at one end of the universal joint is rotatably positioned in the inner cavity of the shank through a bearing, and the top end of the first shaft extends out of the inner cavity and then is inserted into a blind hole in the lower connecting end 8 of the gripper base and then fixed by bolts; the second shaft 19 at the other end of the universal joint is rotatably positioned in the perforation of the connecting rod through a bearing and is connected to the output shaft of the rotating motor.

[0036] A number of rope holes are respectively made on the peripheries of the rope threading adjusting member, the joint flange and the disc, and the a number of rope holes on each component are located on the same circumference (the number of rope holes is the same as the number of the second driving ropes). It can be seen from the figure that the four rope holes on the rope threading connecting member are threaded holes, and each threaded hole fixes a second driving rope 3 through a clamping screw. After each second driving rope is connected to the rope threading adjusting member, it sequentially passes through the rope holes on the joint flange and the rope holes on the disc and is guided by these rope holes, and finally extends into the transmission housing.

[0037] From Figure 11It can be known that: the transmission housing is made with an upper inner cavity for installing the rotary motor and a lower inner cavity for installing the gear-rack structure. The rotary motor is fixed in the upper inner cavity by screws; the axis of the output shaft of the rotary motor is coaxially arranged with the transmission housing, and this output shaft is connected to the second shaft 19 through a coupling (preferably a diaphragm coupling) 20, so as to drive the universal joint. In the lower inner cavity, two pairs of racks 13 that can slide along the length direction are positioned by brackets; the tooth surfaces of the two racks in each pair of racks face each other, and a gear shaft is positioned between the two racks where the gears 14 of the frame are arranged and meshes with the two racks at the same time; the same ends of the two racks are respectively connected to two second driving ropes extending into the transmission housing, and an electric push rod 15 drives the other end of one of the racks (only one of the two racks is provided with an electric push rod; the electric push rod and the rack are connected and fixed by bolts). Obviously, the movement directions of the two racks in each pair of racks are opposite, so as to drive the two second driving ropes to move in opposite directions. It can also be known from the figure that: the axes of the two gears that the two pairs of racks cooperate with are perpendicular to each other and perpendicular to the length direction of the transmission housing; correspondingly, the four racks that cooperate with the two gears are respectively positioned on the four inner walls of the rectangular transmission housing. When the two electric push rods operate simultaneously, wrist joint swings at any angle can be combined, rather than just a single-direction swing.

[0038] In addition, the finger motor, the rotary motor and the electric push rod are respectively connected to the battery through wires, and the battery can be carried by an external robot; these are all prior arts and will not be elaborated here.

[0039] The working principle of the present invention is: after the fruit pose state is collected by the camera, the robot or the operator moves the picking end gripper to the corresponding position with the correct pose (the wrist joint can be deflected to one side by the telescopic adjustment of the electric push rod 15, so as to form the correct grasping pose). When the finger motor rotates forward, the finger envelope is closed by tightening the first driving rope, so as to achieve the purpose of the finger grasping the fruit; after successfully grasping the fruit, the rotary motor drives the universal joint to rotate and then drives the gripper to rotate, so that the fruit can be successfully separated from the branch.

Claims

1. A fruit picking end gripper with wrist joint and rotatable broken handle function, comprising a hand claw capable of holding a round fruit; characterized in that: The end gripper for fruit picking further includes an opening and closing drive assembly for driving the gripper fingers, a swing drive assembly connected to the gripper fingers through a wrist joint, and a rotating mechanism for driving the rotation of the swing drive assembly; The gripper fingers include a plurality of fingers (1) radially arranged on the gripper base (7) and swingable in the direction of the axis of the gripper base; the opening and closing drive assembly includes a finger motor (7.1) fixed on the gripper base and driving the plurality of fingers simultaneously through a first drive rope (9); the wrist joint includes a joint sphere (6) and a joint socket (5) that cooperate with each other, and a universal joint (18) connecting the gripper base is installed in the hollow part of the joint sphere and the joint socket; the swing drive assembly includes a plurality of second drive ropes (3) respectively connected to the wrist joint and an electric push rod (15) driving the gripper base through a gear and rack structure connecting the plurality of second drive ropes; the rotating mechanism includes a rotating motor (21) driving the rotation of the universal joint; The fingers are arc-shaped; each finger is hinged on the gripper base and swings in the direction of the axis of the gripper base, and the outer side of the finger has the potential energy of turning outwards due to the force of a spring; the first drive rope is connected to the finger and applies a moment to swing it towards the same center. One end of the joint sphere has a handle rod (6.1) extending outwards to connect a rope threading adjusting part, and a cavity coaxial with the handle rod and penetrating the joint sphere is made in the joint sphere; one end of the joint socket is equipped with a connecting rod (5.2) extending outwards to connect a disc; a perforation coaxial with the connecting rod and penetrating both ends of the connecting rod is made in the connecting rod; a joint socket flange (5.1) sleeved on the outside of the joint sphere and provided with a lubricating nozzle is also integrally connected with the joint socket through a plurality of bolts. The universal joint is installed in the cavity of the joint sphere; one end of the universal joint is rotatably positioned in the cavity of the handle rod through a bearing and fixed to the gripper base, and the other end is rotatably positioned in the perforation of the connecting rod through a bearing and connected to the output shaft of the rotating motor.

2. The fruit-picking end gripper with wrist joint and rotating broken handle function according to claim 1, characterized in that: The finger motor is installed in a blind hole in the middle of the gripper base, and a reel for pulling the first drive rope is installed on the motor shaft of the finger motor.

3. The fruit-picking end gripper with wrist joint and rotatable broken handle function according to claim 2, wherein: A plurality of rope holes are respectively made in the peripheries of the rope threading adjusting part, the joint flange and the disc, and the plurality of rope holes on each component are located on the same circumference; each second drive rope connecting the rope threading adjusting part sequentially passes through the rope holes on the joint flange and the rope holes on the disc and then extends into the transmission housing (4).

4. The fruit picking end gripper with wrist joint and rotatable broken handle function according to claim 3, wherein: The transmission housing is made with an upper inner cavity for installing the rotating motor and a lower inner cavity for installing the gear and rack structure.

5. The fruit-picking end gripper with wrist joint and rotatable broken handle function according to claim 4, wherein: Two pairs of racks (13) slidable along the length direction are positioned in the lower inner cavity through brackets; the tooth surfaces of the two racks in each pair of racks face each other and are simultaneously engaged with a gear (14) positioned on the frame, and the same ends of the two racks are respectively connected to the two second drive ropes, and another electric push rod drives the other end of one of the racks.

6. The fruit picking end gripper with wrist joint and rotatable broken handle function according to claim 5, characterized in that: The axes of the two gears cooperating with the two pairs of racks are perpendicular to each other and perpendicular to the length direction of the transmission housing.

Images