Manipulator actuating mechanism

Abstract

The invention relates to agricultural equipment. The actuating mechanism for single-fruit picking manipulator includes a support plate (1) carrying a cutting device (5) surrounded with a leaf-pushing device (2). The leaf-pushing device (2) is designed as conical petals (3) forming sectors of a hollow cone when closed, and capable of being opened by a corresponding mechanism (4) for spreading the conical petals (3). Video surveillance cameras (7) are located on the edges of the conical petals (3). The invention is characterized by higher efficiency and accelerates fruit picking making it possible to push through the foliage surrounding the fruit and to accurately determine the position of fruit stalk.

Description

[0001] MANIPULATOR ACTUATING MECHANISM

[0002] FIELD OF TECHNOLOGY

[0003] The invention relates to agricultural equipment, specifically to robotic devices for picking single fruits.

[0004] PRIOR ART

[0005] Various problems have to be addressed when designing effective robotic devices for picking single fruits in the process of harvesting, including the need for precise positioning of devices for detaching a fruit from its stalk in the midst of leaves of the agricultural plant.

[0006] Patent KR20240122033, publication date 2024-08-12, ICL A01D46 / 30, discloses a design of a cutting device for harvesting agricultural crops, which includes a dividing baffle (120) in the form of a rotatable hook capable of diverting the fruit stalk from surrounding stalks, branches, etc. The cutting device also includes a control unit that can distinguish a fruit stalk from the surrounding obstacles such as branches and direct the cutting element to cut the stalk of the selected fruit.

[0007] Patent CN217241505, publication date 2022-08-23, ICL A01D46 / 30, presents a robot designed for harvesting vegetables and fruits. The robot comprises a first manipulator (101), a second manipulator (104), and a mobile mechanism with both manipulators mounted thereupon. The first manipulator is intended for collecting vegetables and fruits, while the second manipulator is used to remove obstacles blocking the target fruit. The robot's database stores both images of vegetables or fruits intended for collection and images of obstacles that block the access to the target fruit.

[0008] Patent CN111602517, publication date 2020-09-01, ICL A01D46 / 30, reveals a method for visual active probing of fruits based on the use of two cameras. A wide-field camera captures a broad view image of the fruit tree, allowing prioritization of collection. A narrowfield camera, which moves together with the manipulator, detects fruits at close range, captures dynamic narrow-field-of-view images, and performs active detection and intelligent decision-making for fruit collection.

[0009] Patent CN118614269, publication date 2024-09-10, ICL A01D46 / 30, discloses a multimodal method for harvesting citrus fruits, as well as a design of manipulator actuating mechanism. The clamping and cutting actuator for citrus harvesting includes a visual sensor system, a tactile sensor system, a clamping component, a cutting component, anda driving component. The visual sensor system comprises cameras used to capture visual information about citrus fruits. The tactile sensor system includes a tactile sensor, a microcontroller, and an electromagnetic valve. Said tactile sensor is mounted on the tactile clamping arm of the clamping component to detect citrus stalks within the clamping area; the clamping component includes a silicone clamping arm. The cutting component consists of a blade and a holder.

[0010] The above design is the closest analog to the case in point.

[0011] Despite the existence of analogs, there remains the problem of creating effective devices for single-piece collection of agricultural products in the conditions where obstacles to harvesting, such as foliage, branches, and other barriers exist.

[0012] DISCLOSURE OF THE INVENTION

[0013] The technical result achieved in the present invention consists of enhanced efficiency and speed of fruit harvesting owing to the opportunity of navigating through the foliage surrounding the fruit and accurately determining the position of fruit stalk.

[0014] The actuator of single-fruit picking manipulator includes a support plate carrying a cutting device, around which a leaf-pushing mechanism is mounted. The leaf-pushing mechanism consists of conical petals representing sectors of a hollow cone in closed position, whereas said conical petals are equipped with a mechanism for pulling them apart to bring them to open position. Video surveillance cameras are mounted on the edges of said conical petals.

[0015] The enhanced efficiency and speed of fruit harvesting is stipulated by the fact that the design of the manipulator actuating mechanism makes it possible to navigate through the surrounding foliage and permits to accurately determine the position of the fruit stalk using video cameras placed on the edges the conical petals. Hence, the accuracy and speed of determining the position of fruit stalk for its eventual cutting improve.

[0016] Among other, the device for pulling conical petals apart includes a hinge having one of its straps fastened to the surface of a conical petal at its base, and the other strap - to the support plate. Said opening device also comprises a rotation gear in the form of a ring fastened to the other side of the support plate and capable of axial rotation. Fixed axles are installed on said ring with levers movably mounted upon said axles. The opposite endof the lever assigned to a conical petal is also movably mounted on a fixed axis at the end of said conical petal.

[0017] Also, video surveillance cameras are installed on the inside of the conical petals, and protective visors are fixed on the outside of the edges of said conical petals.

[0018] Besides, the cutting device is equipped with an extension mechanism.

[0019] Moreover, the actuator is additionally equipped with a device for measuring the distance to fruit stalk based on a linear displacement sensor.

[0020] In addition, the device for measuring the distance to fruit stalk is coaxially installed above the cutting mechanism.

[0021] Additionally, the actuator is equipped with a panoramic surveillance camera. All video cameras, the panoramic surveillance camera and the device for measuring the distance to fruit stalk are connected to a control unit.

[0022] BRIEF DESCRIPTION OF DRAWINGS

[0023] Fig. 1 shows a general view of the manipulator actuating mechanism.

[0024] Fig. 2 shows a side view drawing of the actuating mechanism with conical petals closed.

[0025] Fig. 3 shows a side view drawing of the actuating mechanism with conical petals open.

[0026] Fig. 4 shows a front view drawing of the actuating mechanism with conical petals closed.

[0027] Fig. 5 shows a front view drawing of the actuating mechanism with conical petals open.

[0028] Fig. 6 shows a drawing of a conical petal opening mechanism when the petals are closed.

[0029] Fig. 7 shows a drawing of a conical petal opening mechanism when the petals are open.

[0030] Fig. 8 shows a side view of the profile of a conical petal in closed position.Fig. 9 shows a drawing of the device for measuring the distance to fruit stalk. Fig. 10 shows a drawing of the actuating mechanism with the conical petals open. Fig. 11 shows a drawing of the cutting device.

[0031] Fig. 12 shows a diagram of the manipulator’s actuating mechanism orientation. Fig. 13 shows a top view drawing of rack-and-pinion mechanism.

[0032] Fig. 14 shows a side view drawing of rack-and-pinion mechanism.

[0033] Fig. 15 shows a general view of the manipulator.

[0034] EMBODIMENTS OF THE INVENTION

[0035] The actuating mechanism of fruit picking manipulator includes (Fig. 1 - Fig. 11) a support plate 1 , on which device 2 for pushing leaves aside is mounted. Inside leaf-pushing device 2, a cutting device 5 and a device 6 for measuring the distance to fruit stalk are installed. The leaf-pushing device 2 consists of four conical petals 3, which form a hollow cone when closed. The conical petals 3 are turnable, being attached to the support plate 1 with hinges 11 (Fig. 3 - Fig. 6; Fig. 7 - Fig. 9; Fig. 11 - Fig. 12), Strap 12 of hinge 11 is fixed on the surface of conical petal 3, while strap 13 of hinge 11 is fixed on the support plate 1. Mechanism 4 for opening the conical petals includes a rotary device in the form of a toothed ring 14 (Fig. 7 - Fig. 8; Fig. 11 - Fig. 12). Ring 14 is coupled with a reduction gear 20, which, being driven by a petal-opening motor, turns ring 14 to open conical petals 3 and returns ring 14 to its original position. Each conical petal 3 has an axle 15 rigidly fixed on ring 14, with a similar axle 15 rigidly fixed on the end face 21 of conical petal 3. When ring 14 turns, movable levers 16, which are supported by fixed axles 15, act upon the end face 21 of a corresponding conical petal 3 and turn said petal on hinges 11.

[0036] A cutting tool 5 includes mechanism 17 for cutter extension (Fig. 12). The design of cutting tool also comprises drive 24, which controls a cutter 25. In the drawings, cutter 25 is represented by pruning shears. Knives, saws, and other devices can also be used in this function.

[0037] A device for measuring the distance to fruit stalk can be designed as shown in Fig.10. It includes a movable rod 22 enclosed in housing and capable of returning to its original position under the action of spring 23. Said device is equipped with sensor 9, whichcan be represented by a linear displacement sensor. Specifically, movable rod 22 of the device for measuring distance to fruit stalk can be installed coaxially above the cutting device 5 (Fig.4, Fig.6). The output of the device for measuring distance to fruit stalk is connected to control unit 10.

[0038] An actuating mechanism of manipulator may additionally include a panoramic observation camera 8 mounted on control unit 10 (Fig.1, Fig.3) and directed along the axis of the actuating mechanism of manipulator. The output of panoramic observation camera 8 is connected to control unit 10.

[0039] Video surveillance cameras 7 (Fig. 5, Fig. 6) are mounted on the edges of the conical petals 3 on the inside, while protective canopies 32 are fixed on the outside of edges of the conical petals 3. The outputs of video surveillance cameras 7 are connected to control unit 10.

[0040] The control unit 10 is intended for processing the information from panoramic surveillance camera 8, video surveillance cameras 7, and device 6 for measuring the distance to fruit stalk. Based on the programs stored in the computer of control unit 10, operational commands for all the mechanisms of the manipulator are generated to make actuating device 5 of the manipulator move in the desired direction and perform all the assigned functions.

[0041] Hereinafter, the operation of the actuating device of manipulator is described using grape harvesting as the example. Harvesting of a single grape cluster is a complex task for robotic systems, because grape clusters are usually surrounded by thick and ample foliage and consist of a multitude of berries.

[0042] A suggested design of manipulator equipped with the claimed actuator (Fig. 15) contains support 28, including load-bearing vertical guides 29, on which horizontal guide 30 with carriage 31 is installed. The movement of the horizontal guides in the vertical plane is driven by transfer mechanisms (not shown in the Figures) using rack-and-pinion gears. The movement of carriage 31 along the horizontal guide is also driven by a rack-and-pinion gear.

[0043] Mechanism 4 for driving link 18 of the manipulator is installed at a downward angle to the horizontal plane.The mechanisms used for driving carriage 2 in all directions and mechanism 18 used for driving said link of the manipulator are designed as rack transmissions. A suggested design of rack transmission for mechanism 18 is shown in Fig. 13, Fig. 14.

[0044] The actuating mechanism of manipulator operates as follows. Using the data stored in the control unit and additionally supplied, as in this particular case, by panoramic surveillance camera 8, control unit 10 adjusts the position of carriage 31 and directs the actuating mechanism of manipulator to a possible location of grape clusters. Conical petals 3 are pushed in closed state between the leaves and pulled open on command from control unit 10. The data from video surveillance cameras 7 installed at the edges of conical petals 3 (Fig. 4, Fig. 5) is used for pushing conical petals 3 between the leaves. In closed position of conical petals 3 (Fig. 5), video surveillance cameras 7 are spread apart and direct the movement of manipulator at this stage.

[0045] When conical petals 3 are open, they, together with protective canopies 32, push the leaves apart. Simultaneously, protective canopies 32 protect the field of view of video surveillance cameras 7. After conical petals 3 open (Fig. 5) and grape cluster 26 is detected (Fig. 16), the precision targeting of the manipulator’s actuating mechanism 5 starts.

[0046] When conical petals 3 open, video surveillance cameras 7 also spread apart, and the discrimination ability of the whole system of cameras 7 increases, and the stage of precise guidance of manipulator’s actuating mechanism 5 starts.

[0047] If the distance to stalk has to be measured more accurately, a tactile device 6 for measuring the distance to stalk 27 can be used.

[0048] Based on the data supplied by video surveillance cameras 7, control unit 10 directs rod 22 of device 6 which measures the distance to fruit stalk 27 towards the upper part of stalk 27 of grape cluster 26. Rod 22 starts approaching stalk 27. Their touchdown displaces rod 22, and sensor 9 of device 6 for measuring the distance to fruit stalk 27 (Fig. 10) transmits a signal to control unit 10.

[0049] The need for such a tactile system in aid of device 6 for measuring the distance to stalk 27 is stipulated by the fact that video surveillance cameras 7 cannot always obtain accurate data about the distance to stalk 26. Besides, other known non-contact systemsare vulnerable to interference from signals generated by foliage, branches and grape clusters 26.

[0050] Subsequently, based on all the data about the exact location of stalk 27, control unit 10 extends cutting device 5 to reach the target grape cluster, which is then cut off by cutter 25. The process of collecting grape clusters after they are cut is not examined in this patent application. It can be performed using known methods, for example, transporting cut-off clusters through canvas sleeves, or putting them into a container located under the manipulator’s actuating mechanism 5.

[0051] INDUSTRIAL APPLICABILITY

[0052] The proposed design of the actuating mechanism of manipulator can be used for harvesting various types of agricultural plants, especially in cases when the fruits are hidden by fairly dense foliage.

Claims

CLAIMS1. An manipulator actuating mechanism for a manipulator for single-fruit picking, comprising a support plate with a cutting device mounted thereupon and surrounded by a leaf pushing device; wherein said leaf pushing device is designed as conical petals, constituting sectors of a hollow cone in closed position and capable of opening up under the action of a mechanism for opening conical petals; wherein video surveillance cameras are mounted on the edges of said conical petals.

2. The manipulator actuating mechanism as per claim 1, wherein the device for opening conical petals includes hinges, with one strap of each hinge attached to the surface of a conical petal at its base, and the other strap - to the support plate; said device for opening conical petals also including a rotary mechanism designed as a ring attached to the other side of the support plate and capable of turning around its axis; said ring having fixed axles mounted thereupon and carrying movable levers; whereas, the other end of each lever located at a corresponding conical petal is movably mounted on a fixed axle at the butt end of said conical petal.

3. The manipulator actuating mechanism as per claim 1, wherein video surveillance cameras are installed on the inner side of conical petals, with protective canopies fixed to the outer side of the edges of conical petals.

4. The manipulator actuating mechanism as per claim 1 , wherein the cutting device is equipped with an extension mechanism.

5. The manipulator actuating mechanism as per claim 1 , having a device for measuring distance to fruit stalk in the form of a linear displacement sensor added.

6. The manipulator actuating mechanism as per claims 1 and 5, wherein the device for measuring distance to fruit stalk is installed coaxially above the cutting device.

7. The manipulator actuating mechanism as per claim 1, wherein a panoramic surveillance camera is added.

8. The manipulator actuating mechanism as per claims 1 and 7, wherein video cameras, panoramic surveillance camera and device for measuring distance to fruit stalk are connected to a control unit.

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