Potato picking device, potato force calculation method and adaptive control method

Abstract

The application relates to the field of potato collecting equipment, in particular to a potato picking device, a potato stress calculation method and a self-adaptive control method, the picking device comprising a shell, a shovel blade arranged at the bottom of the front of the shell, a potato poking mechanism and a potato guiding mechanism arranged in the shell from front to back, a collecting box arranged at the rear of the potato guiding mechanism, the collecting box being fixedly connected to the shell and being in communication with the internal space of the shell. The application provides an automatic potato picking device which can automatically complete potato collecting and other actions and avoid damaging potatoes during the collecting process; the picking claw is cyclically rotated and periodically extended and retracted, so that the picking distance is prolonged, the situation of falling during the collecting process is avoided, the potato guiding plate at the rear is prevented from being staggered, and the potatoes or the device are prevented from being damaged by stones.

Description

Technical Field

[0001] This invention relates to the field of potato collecting equipment, and in particular to a potato picking device, a method for calculating the force on potatoes, and an adaptive control method. Background Technology

[0002] The potato industry is developing rapidly, but low mechanization is the main problem restricting its development. Currently, potato harvesting in my country mainly relies on mechanical digging and manual picking. This method has low mechanization, high labor intensity, is time-consuming and costly, thus hindering the industry's development.

[0003] The paper "Key Design of Potato Picking Machine" discloses a potato picking machine. During operation, anti-leakage grids gather potatoes from the edges to the center, and the picking shovel sends the soil-containing potatoes into a separating conveyor chain. The soil falls back to the ground, and the potatoes are conveyed to the rake teeth. The rake teeth lift the potatoes to a high position, throw them out, and after impacting the rubber curtain, they fall into the collection box. Although this machine improves picking efficiency, the rate of potato leakage and damage is still relatively high. The paper "Experimental Study of Potato Picking Device Based on Discrete Element Method" discloses a disc potato picking device. Potatoes spread on the ground by the digging strips of a potato excavator are picked up by the picking disc. When the disc rotates to 3 / 4 of its maximum distance, the potatoes fall onto the guide plate due to gravity and slide onto the conveyor belt, moving to the rear of the device where they are manually bagged by the collection device. This machine has a simple structure and high reliability, but the excessive falling height of the potatoes leads to a significant increase in potato damage. The research paper, "Experimental Study on the Picking Performance of a Spindle-Type Potato Picker," discloses a spindle-type potato picking device. Its main drive shaft drives a roller disc and a spindle shaft to rotate. The roller is connected to a crank and the spindle shaft, rolling within a cam slide to control the trajectory of the spindle. The cam is fixed to the frame. When the picking spindle reaches its lowest point, it extends outside the arc-shaped cover, inserting into the ground to pick up the potato. After the potato rises to its highest point with the spindle, it rolls into the potato collection box, and the spindle retracts to complete the picking operation. During operation, this machine suffers from problems such as soil accumulation due to excessive soil penetration and the slight omission of some potatoes.

[0004] In summary, the potato picking devices developed by different experts and scholars each have their own advantages and disadvantages, but none of them have completely solved the problems of potato leakage, potato damage, and soil accumulation. Summary of the Invention

[0005] This invention aims to solve the above problems and provides a potato picking device and a method for calculating the force on potatoes. The technical solution adopted is as follows:

[0006] A potato picking device includes a housing, with a shovel blade positioned at the bottom front of the housing. Inside the housing, a potato-pulling mechanism and a potato-guiding mechanism are arranged sequentially from front to back. A collection box is positioned behind the potato-guiding mechanism, and the collection box is fixedly connected to the housing and communicates with the internal space of the housing. The potato-pulling mechanism is positioned above the shovel blade and transfers potatoes from the shovel blade to the potato-guiding mechanism. The potato-guiding mechanism includes a potato-guiding wheel, potato-guiding rings, picking claws, and a potato-guiding plate. The potato-guiding wheel is fixedly mounted on the housing and has a sliding groove. Multiple potato-guiding rings rotate synchronously and are coaxially arranged with the potato-guiding wheel. The picking claws intersect with the potato-guiding rings. The system is configured such that a guide ring is fixedly connected to a rotating frame, a picking claw is hinged at the end of the rotating frame, a roller is hinged in the middle of the picking claw, the roller is engaged in a sliding groove and moves along the groove, a guide plate is set between the guide ring and the collection box, and the height of the guide plate gradually decreases; the picking claw gradually extends outward and rotates to the bottom after passing the guide plate from the rear side, and is fully extended when it reaches the bottom of the guide ring, and begins to retract into the guide ring when it rotates upward from the front side to the upper side of the guide ring, until it reaches the guide plate and retracts to its limit position, at which point the rear edge of the picking claw does not exceed the front edge of the guide plate.

[0007] Based on the above scheme, the potato guide plate is composed of multiple strip structures arranged in parallel in the horizontal direction, and the picking claws are correspondingly arranged at the intervals between adjacent strip structures.

[0008] Preferably, the potato guiding mechanism further includes a potato guiding shaft, the rotating frame is fixedly connected to the potato guiding shaft and rotates synchronously, a connecting frame is fixedly provided between the end of the rotating frame and the potato guiding ring, a hinge rod is fixedly provided between the ends of adjacent connecting frames, the hinge rod is coaxially arranged, the end of the picking claw is hinged to the hinge rod, a connecting rod is provided through the middle of the picking claw near the hinge rod, and the roller is rotatably provided at the end of the connecting rod.

[0009] Preferably, the potato-peeling mechanism includes a potato-peeling wheel, a potato-peeling roller, and a potato-peeling shaft. The potato-peeling wheel is fixedly connected to both ends of the potato-peeling shaft and rotates synchronously with the potato-peeling shaft. The potato-peeling roller is fixedly connected between the potato-peeling wheels and is parallel to the potato-peeling shaft. There are multiple potato-peeling rollers, which are evenly distributed circumferentially along the edge of the potato-peeling wheel.

[0010] Preferably, the potato-pulling mechanism further includes a potato-pulling drive mechanism, and the potato-guiding mechanism further includes a potato-guiding drive mechanism, wherein the potato-pulling drive mechanism and the potato-guiding drive mechanism move synchronously.

[0011] Preferably, a vine removal mechanism is provided between the potato guiding mechanism and the collection box. The vine removal mechanism includes a vine removal roller and a vine blocking plate. The vine removal roller is located at the end of the potato guiding plate and is parallel to the axis of the potato guiding ring. The vine removal rollers are arranged in pairs along the longitudinal direction and roll relative to each other. The surface of the vine removal roller is provided with grooves. The vine blocking plate is located behind the vine removal roller. The lower edge of the vine blocking plate is lower than the upper edge of the lower vine removal roller, and the vine blocking plate is made of flexible material.

[0012] Preferably, a plurality of shovel teeth are fixedly provided on the upper side of the shovel blade, the shovel teeth protrude from the surface of the shovel blade, the front end of the shovel teeth is conical and protrudes from the front end of the shovel blade; a grid bar is fixedly connected to the rear of the shovel blade, the grid bar extends from front to back to the bottom of the potato guiding mechanism, the grid bar is multiple, and an interval is provided between adjacent grid bars.

[0013] A method for calculating the force on a potato, wherein the potato moves in the aforementioned potato picking device, the calculation method includes the following steps:

[0014] A1. When the potato is driven to the top of the guide ring by the picking claw, define the hinge point at the end of the picking claw as point A, the hinge point in the middle of the picking claw as point B, the center of rotation of the potato as point O, the center of rotation of the guide ring as point O, and the guide ring rotates at an angular velocity... Rotating at a constant speed;

[0015] A2. Kinematic analysis of the potato and its delivery mechanism yields...

[0016] (1)

[0017] In the formula Let the velocity at point B be in m / s; Let A be the velocity at point A, in m / s; Let B be the velocity of point B relative to point A, in m / s; Let C be the velocity of point C relative to point A, in m / s; Let C be the velocity of point C relative to point B, in m / s;

[0018] A3. According to the vector diagram method, we can obtain...

[0019] (2)

[0020] (3)

[0021] (4)

[0022] (5)

[0023] (6)

[0024] (7)

[0025] (8)

[0026] In the formula: l AO Let A be the distance from point A to point O, in meters. Let ω be the angular velocity of segment AO; α be the angle between the velocity directions of point A and point B, in °; β be the angle between the velocity direction of point A and the velocity direction of point B relative to point A, in °; γ be the angle between the velocity direction of point B relative to point A and the velocity direction of point C relative to point A, in °; ζ be the angle between the velocity direction of point C and the horizontal line, in °; V Cx V is the horizontal component of the velocity at point C, in m / s; Cy Let C be the vertical component of the velocity, in m / s;

[0027] A4. Perform kinematic analysis on the falling process of the potato. Define point D as the initial contact point between the potato and the guide ring during the falling process, and point E as the final contact point between the potato and the guide ring. The DE segment is an arc with a radius of R. DE Point F is the first contact point between the potato and the guide plate, and point G is the first connection point on the guide plate. Segment FG is arc-shaped with a radius of R. FG Point H is the second connection point of the guide plate; segment GH is a straight line; point I is the third connection point of the guide plate and also the lowest point of the guide plate; segment HI is an arc with radius R. HI Point J is the final contact point between the potato and the guide plate, and segment IJ is a straight line; establishing a rectangular coordinate system with point O as the center and OC as the Y-axis, the equation of the potato's trajectory is:

[0028] (9)

[0029] The equations for each line segment are:

[0030] The expression for arc segment DE: (10)

[0031] The expression for the horizontal line segment EF: (11)

[0032] The expression for arc segment FG: (12)

[0033] The expression for the oblique line segment GH: (13)

[0034] The expression for arc segment HI: (14)

[0035] The expression for the oblique straight line segment IJ: (15)

[0036] The piecewise function of the potato's trajectory on each curve segment is:

[0037] (16)

[0038] In the formula, t is the time of potato movement, in seconds; l D l E l F l G l H l I l J The x-coordinates of each point are m and h, respectively. C h D h E h F h G h H h I h J These are the ordinates of each point, m and l, respectively. DE l FG l HI Let x, y, and h be the x-coordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m) and h. DE h FG h HI Let be the ordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m).

[0039] A5. Analyze the forces acting on the potato during its fall. When the potato hits the guide ring or guide plate, it experiences a normal reaction force and a frictional force. The normal reaction force is...

[0040] (17)

[0041] In the formula, v0 is the velocity of the potato when it just contacts the guide ring or guide plate, m / s; θ is the angle between the velocity of the potato when it just contacts the guide ring or guide plate and the tangent at the contact point, °; F N The normal reaction force (N) is the force at the contact surface between the potato and the guide ring or guide plate.

[0042] From the start of the collision until the potato reaches its maximum compression state, the normal reaction force F at the collision contact surface... N Gradually increase from zero to the maximum value F Nm ,but

[0043] (18)

[0044] (19)

[0045] (20)

[0046] (twenty one)

[0047] (twenty two)

[0048] (twenty three)

[0049] (twenty four)

[0050] (25)

[0051] (26)

[0052] (27)

[0053] In the formula, λ is the angle between the tangent at the point where the potato just contacts the guide ring or guide plate and the horizontal line, in °; φ is the angle between the velocity of the potato just contacting the guide ring or guide plate and the horizontal line, in °; F f R is the frictional force when the potato comes into contact with the guide ring or guide plate, in N; Δt is the time from the start of the collision to the maximum compression state, in s; s F is the average radius of the potato, in meters; m is the mass of the potato, in kilograms; F m The maximum net force (N) experienced by a potato when it comes into contact with the guide ring or guide plate; v x The horizontal velocity of the potato when it just touches the guide ring or guide plate, in m / s; v y denoted as ρ, the vertical velocity of the potato when it just contacts the guide ring or guide plate, in m / s; μ is the coefficient of friction of the guide ring or guide plate.

[0054] An adaptive control method for a potato picking device, using the aforementioned potato picking device, includes the following steps:

[0055] B1. Periodically collect the rotational speed V0 of the potato guide ring of the picking device and the torque T0 of the potato guide mechanism;

[0056] B2. Determine whether the torque T0 is within the preset range; if it is not within the preset range, proceed to step C1; if it is within the preset range, proceed to step D1.

[0057] C1. Input the collected potato guide ring speed V0 and potato guide mechanism torque T0 into the first BP neural network to calculate the potato guide ring speed V1 at the next moment;

[0058] C2. Input the potato guide ring speed V1 into the PID controller, and the PID controller outputs the adjusted potato guide ring speed V1. The system input, system output and system error of the PID controller are input into the second BP neural network. The second BP neural network calculates and outputs the adjusted integral control coefficient, proportional control coefficient and derivative control coefficient of the PID controller.

[0059] C3. Collect the torque T1 at the next moment and proceed to step B2;

[0060] D1. Record the collected potato guide ring speed V0 and potato guide mechanism torque T0 as a set of data;

[0061] D2. When the data sample records are full (10 sets), the dataset is updated using a cyclic overwrite method.

[0062] D3. Input the updated dataset into the first BP neural network for training, and update the weights of the first BP neural network.

[0063] Based on the above scheme, the initial dataset of the adaptive system contains 200 sets of data samples. The dataset is randomly divided into training set and validation set in an 8:2 ratio. In the initial stage of adaptation, the allowable variation range of the pre-set potato guide mechanism torque is increased to a times the rated allowable variation range. Each time the dataset is updated, the allowable variation range of the potato guide mechanism torque is reduced proportionally until, after 20 updates of the dataset, the allowable variation range of the potato guide mechanism torque is reduced to the rated allowable variation range, and the initial dataset is completely covered.

[0064] The beneficial effects of this invention are as follows:

[0065] 1. An automatic potato picking device is proposed, which can automatically complete potato harvesting, preliminary soil screening, vine removal and collection, reducing the throwing height and throwing distance during the potato collection process and avoiding damage to the potatoes during collection.

[0066] 2. The picking claws, which rotate in a cycle and extend and retract periodically, can extend the picking distance and prevent potatoes from falling during collection. They can also prevent them from interfering with the potato guide plate at the rear, thus avoiding damage to the potatoes or the device from stones.

[0067] 3. By analyzing and calculating the force and kinematics during the potato throwing process, the integrity and non-damage rate of potatoes during collection can be effectively improved;

[0068] 4. An adaptive control method for the picking device is proposed, which can learn the indicators in the working environment autonomously, so that the various mechanisms of the picking device match the forward speed of the picking device, thereby improving the picking efficiency. Attached Figure Description

[0069] Figure 1 : Schematic diagram of the structure of the present invention;

[0070] Figure 2 : Schematic diagram of the internal structure of the casing of this invention;

[0071] Figure 3 : Front view of the internal structure of the casing of the present invention;

[0072] Figure 4 : Enlarged view of a portion of the potato guiding mechanism of this invention;

[0073] Figure 5 : A schematic diagram of the kinematic analysis of the potato guiding mechanism of this invention;

[0074] Figure 6 This invention Figure 5 Simplified model diagram of kinematic analysis in the middle;

[0075] Figure 7 This invention provides a vector decomposition diagram of potato velocity.

[0076] Figure 8 : Schematic diagram of the potato movement direction in this invention;

[0077] Figure 9 : A schematic diagram of the potato movement path in this invention;

[0078] Figure 10 This invention provides a schematic diagram of the forces acting on a potato during a projectile motion.

[0079] Figure 11 : Flowchart of the adaptive control method of this invention;

[0080] Figure 12 : Schematic diagram of the adaptive control system of this invention;

[0081] Figure 13 : Diagram of the first neural network structure of this invention;

[0082] Figure 14 : Diagram of the second neural network structure of this invention. Detailed Implementation

[0083] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0084] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0085] In the description of this invention, it should be understood that the terms "center," "length," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," and "inner," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0086] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0087] like Figures 1 to 4 As shown, a potato picking device includes a housing 11, with depth-limiting wheels 13 and a connecting frame on the housing 11. In use, the picking device can be moved by fixing the front tractor or other driving equipment to the connecting frame.

[0088] A shovel blade 21 is provided at the bottom front of the shell 11. A potato-pulling mechanism and a potato-guiding mechanism are arranged sequentially from front to back inside the shell 11. A collection box 12 is provided behind the potato-guiding mechanism. The collection box 12 is fixedly connected to the shell 11 and communicates with the internal space of the shell 11 to collect potatoes inside the shell 11.

[0089] The upper side of the shovel blade 21 is fixedly provided with shovel teeth 22. There are multiple shovel teeth 22. The shovel teeth 22 protrude from the surface of the shovel blade 21. The front end of the shovel teeth 22 is conical and protrudes from the front end of the shovel blade 21, which facilitates shoveling potatoes in the soil and guiding them onto the shovel blade 21. The rear of the shovel blade 21 is fixedly connected with grid bars 23. The grid bars 23 extend from front to back to the bottom of the potato guiding mechanism. There are multiple grid bars 23. There are intervals between adjacent grid bars 23, which facilitates the catching of potatoes that fall when the potatoes move at the potato pulling mechanism and the potato guiding mechanism. At the same time, the soil attached to the potatoes is removed and falls into the ground through the grid bars 23.

[0090] The potato-pulling mechanism is positioned above the shovel blade 21 and transfers the potatoes on the shovel blade 21 to the potato-guiding mechanism. The potato-pulling mechanism includes a potato-pulling wheel 31, potato-pulling rollers 32, and a potato-pulling shaft 33. The potato-pulling wheel 31 is fixedly connected to both ends of the potato-pulling shaft 33 and rotates synchronously with the shaft. The potato-pulling rollers 32 are fixedly connected between the potato-pulling wheels 31 and are parallel to the shaft 33. There are multiple potato-pulling rollers 32, evenly distributed circumferentially along the edge of the potato-pulling wheel 31. When the potato-pulling wheel 31 rotates, the potato-pulling rollers 32 lift the potatoes from the shovel blade 21 and, following the rotation of the potato-pulling wheel 31, transfer the potatoes to the potato-guiding mechanism.

[0091] The potato guiding mechanism includes a potato guiding wheel 411, a potato guiding ring 424, a picking claw 431, and a potato guiding plate 44. The potato guiding wheel 411 is fixedly mounted on the housing 11 and has a sliding groove 412. There are multiple potato guiding rings 424, which rotate synchronously and are coaxially mounted with the potato guiding wheel 411. The picking claw 431 is staggered with the potato guiding ring 424. The potato guiding ring 424 is fixedly connected to a rotating frame 422. The end of the picking claw 431 is hinged to the rotating frame 422, and a roller 432 is hinged to the middle of the picking claw 431. The roller 432 is engaged in the sliding groove 412 and moves along the sliding groove 412. Specifically, the potato guiding mechanism further includes a potato guiding shaft 421, a rotating frame 422 fixedly connected to the potato guiding shaft 421 and rotating synchronously, a connecting frame 423 fixedly provided between the end of the rotating frame 422 and the potato guiding ring 424, a hinge rod fixedly provided between the ends of adjacent connecting frames 423, the hinge rod being coaxially arranged, the end of the picking claw 431 being hinged to the hinge rod, a connecting rod 433 being provided through the middle of the picking claw 431 near the hinge rod, and the roller 432 being rotatably provided at the end of the connecting rod 433.

[0092] The potato guide plate 44 is disposed between the potato guide ring 424 and the collection box 12, and the height of the potato guide plate 44 gradually decreases; the potato guide plate 44 is composed of strip structures, and there are multiple strip structures arranged in parallel in the horizontal direction, with the picking claws 431 correspondingly disposed at the interval between adjacent strip structures.

[0093] The picking claw 431 gradually extends outward and rotates towards the bottom after passing the potato guide plate 44 on the rear side. When the picking claw 431 reaches the bottom of the potato guide ring 424, it is fully extended, which facilitates the retrieval of potatoes that have fallen between the potato-picking rollers 32 when moving forward from the bottom, and continues to move. When the picking claw 431 rotates upward from the front side to the upper side of the potato guide ring 424, it begins to retract into the potato guide ring 424 until it reaches the potato guide plate 44 and retracts to its limit position. At this time, the rear edge of the picking claw 431 does not exceed the front edge of the potato guide plate 44, thereby preventing the picking claw 431 from cutting the potatoes when it crosses the potato guide plate 44, and also preventing stones and other debris falling on the potato guide plate 44 from cutting the potatoes.

[0094] The potato-pulling mechanism further includes a potato-pulling drive mechanism 34, and the potato-guiding mechanism further includes a potato-guiding drive mechanism 45. The potato-pulling drive mechanism 34 and the potato-guiding drive mechanism 45 move synchronously. The potato-pulling drive mechanism 34 and the potato-guiding drive mechanism 45 can be mutually meshing gear transmission mechanisms.

[0095] A vine-removing mechanism is provided between the potato guiding mechanism and the collection box 12. This mechanism includes vine-removing rollers 51 and vine-blocking plates 52. The vine-removing rollers 51 are located at the end of the potato guiding plate 44 and parallel to the axis of the potato guiding ring 424. The vine-removing rollers 51 are arranged in pairs along the longitudinal direction and roll relative to each other. Grooves are irregularly shaped and distributed throughout the surface of each vine-removing roller 51 to wrap around and separate any stray vines. The vine-blocking plate 52 is located behind the vine-removing rollers 51, with its lower edge lower than the upper edge of the lower vine-removing roller 51. The vine-blocking plate 52 is made of flexible material. The two vine-removing rollers 51 roll relative to each other from the outside to the inside towards the potato guiding plate 44, separating the vines from the potatoes. The separated potatoes fall into the collection box 12 after passing through the vine-blocking plate 52.

[0096] A method for calculating the force on a potato, wherein the potato moves in the aforementioned potato picking device, the calculation method includes the following steps:

[0097] A1. As Figure 5 and Figure 6 As shown, when the potato is driven by the picking claw 431 to the top of the guide ring 424, the hinge point at the end of the picking claw 431 is defined as point A, the hinge point in the middle of the picking claw 431 is defined as point B, the rotation center of the potato is defined as point O, the rotation center of the guide ring 424 is defined as point O, and the guide ring 424 rotates at an angular velocity... Rotating at a constant speed;

[0098] A2. Kinematic analysis of the potato and its delivery mechanism yields...

[0099] (1)

[0100] In the formula Let the velocity at point B be in m / s; Let A be the velocity at point A, in m / s; Let B be the velocity of point B relative to point A, in m / s; Let C be the velocity of point C relative to point A, in m / s; Let C be the velocity of point C relative to point B, in m / s;

[0101] A3. For example Figure 7 As shown, according to the vector diagram method, we can obtain...

[0102] (2)

[0103] (3)

[0104] (4)

[0105] (5)

[0106] (6)

[0107] (7)

[0108] (8)

[0109] In the formula: l AO Let A be the distance from point A to point O, in meters. Let ω be the angular velocity of segment AO; α be the angle between the velocity directions of point A and point B, in °; β be the angle between the velocity direction of point A and the velocity direction of point B relative to point A, in °; γ be the angle between the velocity direction of point B relative to point A and the velocity direction of point C relative to point A, in °; ζ be the angle between the velocity direction of point C and the horizontal line, in °; V Cx V is the horizontal component of the velocity at point C, in m / s; Cy Let C be the vertical component of the velocity, in m / s;

[0110] A4. Perform kinematic analysis on the falling process of potatoes, such as... Figure 8 and Figure 9 As shown, point D is defined as the initial contact point between the potato and the guide ring 424 during the potato's fall, and point E is the final contact point between the potato and the guide ring 424. Segment DE is an arc with a radius of R. DE Point F is the first contact point between the potato and the guide plate 44, and point G is the first connection point on the guide plate 44. The FG segment is arc-shaped with a radius of R. FG Point H is the second connection point of the guide plate 44. The GH segment is a straight line. Point I is the third connection point of the guide plate 44 and is also the lowest point of the guide plate 44. The HI segment is an arc with a radius of R. HIPoint J is the final contact point between the potato and the guide plate 44, and segment IJ is a straight line; establishing a rectangular coordinate system with point O as the center and OC as the Y-axis, the equation of the potato's trajectory is:

[0111] (9)

[0112] The equations for each line segment are:

[0113] The expression for arc segment DE: (10)

[0114] The expression for the horizontal line segment EF: (11)

[0115] The expression for arc segment FG: (12)

[0116] The expression for the oblique line segment GH: (13)

[0117] The expression for arc segment HI: (14)

[0118] The expression for the oblique straight line segment IJ: (15)

[0119] The piecewise function of the potato's trajectory on each curve segment is:

[0120] (16)

[0121] In the formula, t is the time of potato movement, in seconds; l D l E l F l G l H l I l J The x-coordinates of each point are m and h, respectively. C h D h E h F h G h H h I h J These are the ordinates of each point, m and l, respectively. DE l FG l HI Let x, y, and h be the x-coordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m) and h. DE hFG h HI Let be the ordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m).

[0122] A5. Analyze the forces acting on the potato during its fall, such as... Figure 10 As shown, when a potato falls onto the guide ring 424 or guide plate 44, the potato begins to contact the guide plate or guide ring and generates an elastic force. The acceleration is approximately linearly related to time, gradually increasing with the increase of the collision time. When the potato is no longer compressed, its elastic deformation gradually recovers, and the acceleration gradually decreases until it decreases to 0, completing the recovery. During this process, the potato is subjected to the normal reaction force and frictional force of the guide ring 424 or guide plate 44, where the normal reaction force is...

[0123] (17)

[0124] In the formula, v0 is the velocity of the potato when it just contacts the guide ring 424 or the guide plate 44, in m / s; θ is the angle between the velocity of the potato when it just contacts the guide ring 424 or the guide plate 44 and the tangent at the contact point, in °; F N The normal reaction force (N) is the force at the contact surface between the potato and the guide ring 424 or guide plate 44.

[0125] From the start of the collision until the potato reaches its maximum compression state, the normal reaction force F at the collision contact surface... N Gradually increase from zero to the maximum value F Nm ,but

[0126] (18)

[0127] (19)

[0128] (20)

[0129] (twenty one)

[0130] (twenty two)

[0131] (twenty three)

[0132] (twenty four)

[0133] (25)

[0134] (26)

[0135] (27)

[0136] In the formula, λ is the angle between the tangent at the contact point of the potato just contacting the guide ring 424 or guide plate 44 and the horizontal line, in °; φ is the angle between the velocity of the potato just contacting the guide ring 424 or guide plate 44 and the horizontal line, in °; F f R is the frictional force when the potato comes into contact with the guide ring 424 or the guide plate 44, in N; Δt is the time from the start of the collision to the maximum compression state, in s; s F is the average radius of the potato, in meters; m is the mass of the potato, in kilograms; F m The maximum net force, N, is the force exerted on the potato when it comes into contact with the guide ring 424 or the guide plate 44. x The horizontal velocity of the potato when it just touches the guide ring 424 or the guide plate 44, in m / s; v y is the vertical velocity of the potato when it just contacts the guide ring 424 or the guide plate 44, in m / s; μ is the coefficient of friction of the guide ring 424 or the guide plate 44.

[0137] By consulting relevant literature, the ultimate destructive force of a potato is found to be 86.76 N. Let the ultimate destructive force of a potato be F. 极 When a potato falls onto the guide plate or guide ring, it experiences an instantaneous force F. m It should be less than F 极 By adjusting the position of the highest point in the potato transport path, the instantaneous force F is ensured. m It should be less than F 极 This helps prevent damage to the potatoes.

[0138] When the speed of the potato harvester increases while the rotation speed of the guide mechanism remains constant, potatoes accumulate, leading to a decrease in the harvester's efficiency. Conversely, when the harvester slows down while the guide mechanism's rotation speed remains constant, it results in a waste of the harvester's power resources. Furthermore, potato harvesters operate in complex and varied environments, influenced by a combination of factors such as soil conditions (clay and sandy loam), terrain (plains, hills, and mountains), and plot yield. These diverse operating environments significantly impact the efficiency of the potato harvesting and collection system.

[0139] An adaptive control method for a potato picking device, using the aforementioned potato picking device, such as... Figures 11 to 14 As shown, it includes the following steps:

[0140] B1. Periodically collect the rotational speed V0 of the guide ring of the picking device and the torque T0 of the guide mechanism; the torque T0 of the guide mechanism can be measured by installing a torque sensor on the guide shaft 421 or other components, or the total torque of the guide mechanism can be obtained by measuring and calculating the torque in parts.

[0141] (28)

[0142] In the formula To pick up the potato-soil mixture on the pick-up claw 431 and generate torque on the guide shaft 421, The torque generated by the picking claw 431 on the guide shaft 421, The torque generated by the rotating frame 422 on the guide shaft 421, The torque generated by the friction between the guide shaft 421, the bearing, and the bearing housing during rotation;

[0143] B2. Determine whether the torque T0 is within the preset range; if it is not within the preset range, proceed to step C1; if it is within the preset range, proceed to step D1.

[0144] C1. Input the collected potato guide ring speed V0 and potato guide mechanism torque T0 into the first BP neural network to calculate the potato guide ring speed V1 at the next moment;

[0145] C2. Input the potato guide ring speed V1 into the PID controller, and the PID controller outputs the adjusted potato guide ring speed V1. The system input r(k) and system output y of the PID controller are... out The integral control coefficient, proportional control coefficient, and derivative control coefficient of the adjusted PID controller are calculated and output through the second BP neural network, and the system error e(k) and system error e(k) are input into the second BP neural network.

[0146] C3. Collect the torque T1 at the next moment and proceed to step B2;

[0147] D1. Record the collected potato guide ring speed V0 and potato guide mechanism torque T0 as a set of data;

[0148] D2. When the data sample records are full (10 sets), the dataset is updated using a cyclic overwrite method.

[0149] D3. Input the updated dataset into the first BP neural network for training, and update the weights of the first BP neural network.

[0150] The adaptive system included in this scheme includes a learning system and a control system. The learning system includes training a first BP neural network to fit the functional relationship of key indicators of the current working environment. The control system is used to regulate the rotational speed V1 of the guide ring for each output.

[0151] The initial dataset of the learning system in the adaptive system contains 200 data samples. The dataset is randomly divided into training and validation sets in an 8:2 ratio. Since there may be too few successful adjustment samples in the initial and early stages of adaptation, failing to trigger the dataset update, the allowable variation range of the pre-set potato guide mechanism torque is increased to a times the rated allowable variation range during the initial adaptive stage. Each time the dataset is updated, the allowable variation range of the potato guide mechanism torque is proportionally reduced until, after 20 dataset updates, the allowable variation range of the potato guide mechanism torque is reduced to the rated allowable variation range, and the initial dataset is completely covered.

[0152] The present invention has been described above by way of example, but the present invention is not limited to the specific embodiments described above. Any modifications or variations made based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A potato picking device, characterized in that, The device includes a housing (11), a shovel (21) at the bottom front of the housing (11), a potato-pulling mechanism and a potato-guiding mechanism arranged sequentially from front to back inside the housing (11), and a collection box (12) arranged behind the potato-guiding mechanism. The collection box (12) is fixedly connected to the housing (11) and communicates with the internal space of the housing (11). The potato-pulling mechanism is arranged above the shovel (21) and transfers the potatoes on the shovel (21) to the potato-guiding mechanism. The potato-guiding mechanism includes a potato-guiding wheel (411), a potato-guiding ring (424), a picking claw (431), and a potato-guiding plate (44). The potato-guiding wheel (411) is fixedly arranged on the housing (11), and a groove (412) is provided on the potato-guiding wheel (411). There are multiple potato-guiding rings (424), which rotate synchronously and are coaxially arranged with the potato-guiding wheel (411). The picking claw (431) is staggered with the potato-guiding ring (424). 24) A fixed rotating frame (422) is connected, and the end of the picking claw (431) is hinged to the rotating frame (422). A roller (432) is hinged to the middle of the picking claw (431). The roller (432) is engaged in the slide groove (412) and moves along the slide groove (412). The guide plate (44) is set between the guide ring (424) and the collection box (12), and the height of the guide plate (44) gradually decreases. The picking claw (431) is in After passing the guide plate (44), the rear side gradually extends outward and rotates to the bottom. When the picking claw (431) reaches the bottom of the guide ring (424), it extends completely. When the picking claw (431) rotates upward from the front side to the upper side of the guide ring (424), it begins to retract into the guide ring (424) until it reaches the guide plate (44) and retracts to the limit position. At this time, the rear edge of the picking claw (431) does not exceed the front edge of the guide plate (44).

2. The potato picking device according to claim 1, characterized in that, The potato guide plate (44) is composed of strip structures, and there are multiple strip structures arranged in parallel in the horizontal direction. The picking claws (431) are correspondingly arranged at the interval between adjacent strip structures.

3. The potato picking device according to claim 1, characterized in that, The potato guiding mechanism also includes a potato guiding shaft (421). The rotating frame (422) is fixedly connected to the potato guiding shaft (421) and rotates synchronously. A connecting frame (423) is fixedly provided between the end of the rotating frame (422) and the potato guiding ring (424). A hinge rod is fixedly provided between the ends of adjacent connecting frames (423). The hinge rod is coaxially provided. The end of the picking claw (431) is hinged to the hinge rod. A connecting rod (433) is provided through the middle of the picking claw (431) near the hinge rod. The roller (432) is rotatably provided at the end of the connecting rod (433).

4. The potato picking device according to claim 1, characterized in that, The potato-pulling mechanism includes a potato-pulling wheel (31), a potato-pulling roller (32), and a potato-pulling shaft (33). The potato-pulling wheel (31) is fixedly connected to both ends of the potato-pulling shaft (33) and rotates synchronously with the potato-pulling shaft (33). The potato-pulling roller (32) is fixedly connected between the potato-pulling wheels (31) and is parallel to the potato-pulling shaft (33). There are multiple potato-pulling rollers (32), which are evenly distributed circumferentially along the edge of the potato-pulling wheel (31).

5. A potato picking device according to claim 1, characterized in that, The potato-pulling mechanism also includes a potato-pulling drive mechanism (34), and the potato-guiding mechanism also includes a potato-guiding drive mechanism (45). The potato-pulling drive mechanism (34) and the potato-guiding drive mechanism (45) move synchronously.

6. The potato picking device according to claim 1, characterized in that, A vine removal mechanism is provided between the potato guiding mechanism and the collection box (12). The vine removal mechanism includes a vine removal roller (51) and a vine blocking plate (52). The vine removal roller (51) is located at the end of the potato guiding plate (44) and is parallel to the axis of the potato guiding ring (424). The vine removal rollers (51) are arranged in pairs along the longitudinal direction and roll relative to each other. The surface of the vine removal roller (51) is provided with a groove. The vine blocking plate (52) is located behind the vine removal roller (51). The lower edge of the vine blocking plate (52) is lower than the upper edge of the lower vine removal roller (51), and the vine blocking plate (52) is made of flexible material.

7. A potato picking device according to claim 1, characterized in that, The upper side of the shovel blade (21) is fixedly provided with shovel teeth (22), and there are multiple shovel teeth (22). The shovel teeth (22) are set to protrude from the surface of the shovel blade (21). The front end of the shovel teeth (22) is conical and protrudes from the front end of the shovel blade (21). The rear of the shovel blade (21) is fixedly connected with grid bars (23). The grid bars (23) extend from front to back to the bottom of the potato guiding mechanism. There are multiple grid bars (23), and there is a gap between adjacent grid bars (23).

8. A method for calculating the forces acting on a potato, characterized in that, The potato moves in the potato picking device according to any one of claims 1-7, and the calculation method includes the following steps: A1. When the potato is driven by the picking claw (431) to the top of the guide ring (424), the hinge point at the end of the picking claw (431) is defined as point A, the hinge point in the middle of the picking claw (431) is defined as point B, the rotation center of the potato is defined as point O, the rotation center of the guide ring (424) is defined as point O, and the guide ring (424) rotates at an angular velocity... Rotating at a constant speed; A2. Kinematic analysis of the potato and its delivery mechanism yields... （1） In the formula Let the velocity at point B be in m / s; Let A be the velocity at point A, in m / s; Let B be the velocity of point B relative to point A, in m / s; Let C be the velocity of point C relative to point A, in m / s; Let C be the velocity of point C relative to point B, in m / s; A3. According to the vector diagram method, we can obtain... （2） （3） （4） （5） （6） （7） （8） In the formula: l AO Let A be the distance from point A to point O, in meters. Let ω be the angular velocity of segment AO; α be the angle between the velocity directions of point A and point B, in °; β be the angle between the velocity direction of point A and the velocity direction of point B relative to point A, in °; γ be the angle between the velocity direction of point B relative to point A and the velocity direction of point C relative to point A, in °; ζ be the angle between the velocity direction of point C and the horizontal line, in °; V Cx V is the horizontal component of the velocity at point C, in m / s; Cy Let C be the vertical component of the velocity, in m / s; A4. Perform kinematic analysis on the falling process of the potato, define point D as the initial contact point between the potato and the guide ring (424) during the falling process, point E as the final contact point between the potato and the guide ring (424), and segment DE as an arc with radius R. DE Point F is the first contact point between the potato and the guide plate (44), and point G is the first connection point on the guide plate (44). The FG segment is arc-shaped with a radius of R. FG Point H is the second connection point of the guide plate (44), segment GH is a straight line, point I is the third connection point of the guide plate (44) and point I is the lowest point of the guide plate (44), segment HI is an arc with radius R. HI Point J is the final contact point between the potato and the guide plate (44), and segment IJ is a straight line; a rectangular coordinate system is established with point O as the center and OC as the Y-axis, then the equation of the potato's trajectory is: （9） The equations for each line segment are: The expression for arc segment DE: (10) The expression for the horizontal line segment EF: (11) The expression for arc segment FG: (12) The expression for the oblique line segment GH: (13) The expression for arc segment HI: (14) The expression for the oblique straight line segment IJ: (15) The piecewise function of the potato's trajectory on each curve segment is: （16） In the formula, t is the time of potato movement, in seconds; l D l E l F l G l H l I l J The x-coordinates of each point are m and h, respectively. C h D h E h F h G h H h I h J These are the ordinates of each point, m and l, respectively. DE l FG l HI Let x, y, and h be the x-coordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m) and h. DE h FG h HI Let be the ordinates of the centers of arcs DE, FG, and HI, respectively, in meters (m). A5. Analyzing the forces acting on the potato during its fall, when the potato hits the guide ring (424) or guide plate (44), the potato experiences a normal reaction force and a frictional force from the guide ring (424) or guide plate (44), where the normal reaction force is... （17） In the formula, v0 is the velocity of the potato when it just contacts the guide ring (424) or guide plate (44), m / s; θ is the angle between the velocity of the potato when it just contacts the guide ring (424) or guide plate (44) and the tangent at the contact point, °; F N N represents the normal reaction force at the contact surface between the potato and the guide ring (424) or guide plate (44). From the start of the collision until the potato reaches its maximum compression state, the normal reaction force F at the collision contact surface... N Gradually increase from zero to the maximum value F Nm ,but （18） （19） （20） （21） （22） （23） （24） （25） （26） （27） In the formula, λ is the angle between the tangent of the contact point of the potato just contacting the guide ring (424) or guide plate (44) and the horizontal line, °; φ is the angle between the velocity of the potato just contacting the guide ring (424) or guide plate (44) and the horizontal line, °; F f R is the frictional force when the potato comes into contact with the guide ring (424) or guide plate (44), in N; Δt is the time from the start of the collision to the maximum compression state, in s; s F is the average radius of the potato, in meters; m is the mass of the potato, in kilograms; F m The maximum net force, N, is the force exerted on a potato when it comes into contact with the guide ring (424) or guide plate (44). x v is the horizontal velocity of the potato when it just touches the guide ring (424) or guide plate (44), in m / s; y is the vertical velocity of the potato when it just comes into contact with the guide ring (424) or guide plate (44), in m / s; μ is the coefficient of friction of the guide ring (424) or guide plate (44).

9. An adaptive control method for a potato picking device, characterized in that, Using the potato picking device according to any one of claims 1-7, the steps include: B1. Periodically collect the rotational speed V0 of the potato guide ring of the picking device and the torque T0 of the potato guide mechanism; B2. Determine whether the torque T0 is within the preset range; if it is not within the preset range, proceed to step C1; if it is within the preset range, proceed to step D1. C1. Input the collected potato guide ring speed V0 and potato guide mechanism torque T0 into the first BP neural network to calculate the potato guide ring speed V1 at the next moment; C2. Input the potato guide ring speed V1 into the PID controller, and the PID controller outputs the adjusted potato guide ring speed V1. The system input, system output and system error of the PID controller are input into the second BP neural network. The second BP neural network calculates and outputs the adjusted integral control coefficient, proportional control coefficient and derivative control coefficient of the PID controller. C3. Collect the torque T1 at the next moment and proceed to step B2; D1. Record the collected potato guide ring speed V0 and potato guide mechanism torque T0 as a set of data; D2. When the data sample records are full (10 sets), the dataset is updated using a cyclic overwrite method. D3. Input the updated dataset into the first BP neural network for training, and update the weights of the first BP neural network.

10. The adaptive control method for a potato picking device according to claim 9, characterized in that, The initial dataset of the adaptive system contains 200 data samples. The dataset is randomly divided into training and validation sets in an 8:2 ratio. In the initial adaptive phase, the allowable variation range of the pre-set potato guide mechanism torque is increased to a times the rated allowable variation range. Each time the dataset is updated, the allowable variation range of the potato guide mechanism torque is reduced proportionally until, after 20 updates, the allowable variation range of the potato guide mechanism torque is reduced to the rated allowable variation range, and the initial dataset is completely covered.

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