Reciprocating soybean inter-plant weeding and avoiding device and control method

Abstract

The invention discloses a reciprocating soybean inter-row seedling avoidance and weeding device and a control method. The device comprises a detection system, a control system, and a weeding mechanism. The detection system comprises a laser distance sensor, which is arranged on the weeding mechanism and is used to measure distance data between the laser distance sensor and a measured object. The control system reads the distance data detected by the laser distance sensor in real time. The weeding mechanism comprises a frame and a servo drive component and a weeding component arranged on the frame. The reciprocating soybean inter-row seedling avoidance and weeding device and the control method obtain distance data of the measured object through the laser distance sensor, and determine whether it is a soybean plant through a soybean recognition model programmed in a PLC controller. Comb teeth below the weeding mechanism are arranged side by side and are formed into contoured comb teeth, which can effectively avoid a decrease in recognition rate caused by environmental factors such as light and shadow, and can detect and weed in real time.

Description

Technical Field

[0001] The invention belongs to the technical field of agricultural weeding, in particular to a reciprocating soybean inter-plant seedling avoidance weeding device and a control method. Background Art

[0002] In recent years, with the advancement of agricultural science and technology, increasing soybean yields has become a key focus of agricultural development. However, soybeans grow in a complex environment, and weed growth can impact soybeans by competing with early-stage soybean plants for light, water, and nutrients. Left unchecked, this can seriously compromise soybean quality and yield. Physical and mechanical weed control during the early stages of soybean growth is an effective way to ensure soybean yield and quality, and is also a crucial measure to reduce environmental pollution and ensure personnel safety. With the development of new agricultural technologies, weed control techniques are constantly innovating. Beyond traditional manual weeding, methods such as biological weed control, chemical weed control, thermal weed control, and physical and mechanical weed control have emerged. Biological weed control suffers from the inability to eradicate weeds and is significantly affected by climatic conditions. Chemical weed control offers the advantages of being easy and labor-efficient, but it can also impact the environment and accelerate the development of weed resistance. Thermal weed control is only applicable to large, plain areas and is subject to significant limitations. Physical and mechanical weed control offers the advantages of being pollution-free, environmentally friendly, and labor-efficient, but it still suffers from low weed control rates and high seedling damage when weeding between soybean plants.

[0003] To achieve simple field weeding with high removal rates and low seedling damage, soybean inter-row weeding devices have been explored and researched. Laser ranging sensors are widely used for identifying soybean plants and weeds. The laser ranging sensors collect plant information, and a soybean recognition model programmed by a programmable logic controller (PLC) distinguishes between soybean plants and weeds. The PLC then sends instructions to a servo driver, indirectly controlling the motor that drives the soybean inter-row weeding mechanism to avoid seedlings and remove weeds. This achieves real-time seedling avoidance and weed removal with high efficiency, pollution-free operation, and ease of operation, making it an environmentally friendly physical and mechanical weeding method. Currently, weeding actuators are a major factor limiting weeding rates and seedling damage rates. The material and shape of these actuators can result in incomplete weeding and can even sever soybean rhizomes if they accidentally touch soybean plants. Summary of the Invention

[0004] Purpose of the invention: To provide a reciprocating soybean inter-plant seedling avoidance weeding device and control method, so as to solve the problem in the prior art that the weeding execution component is one of the main factors restricting the weeding rate and seedling injury rate, the material and shape of the weeding execution component will lead to incomplete weeding, and even cut off the roots and stems of the soybean plants when accidentally touching the soybean plants.

[0005] Technical solution:

[0006] A reciprocating soybean inter-row weeding device includes a detection system, a control system, and a weeding mechanism. The detection system includes a laser ranging sensor, which is arranged on the weeding mechanism and is used to measure the distance data between the laser ranging sensor and the measured object, wherein the measured object includes soybean plants and weeds.

[0007] The control system reads the distance data detected by the laser ranging sensor in real time. The control system includes a PLC controller, an analog input module, a connection module, and a servo power module. The PLC controller writes a soybean recognition model program based on the diameter and height of soybean plants and the distance between soybean plants. The laser ranging sensor transmits the generated analog signal to the PLC controller through the analog input module. The PLC controller is connected to the servo power module through the connection module.

[0008] The weeding mechanism includes a frame and a servo drive assembly and a weeding assembly arranged on the frame. The weeding assembly includes two comb plates and contoured elastic comb teeth. A plurality of contoured elastic comb teeth arranged side by side at equal intervals are welded under each of the comb plates. The servo drive assembly drives the two comb plates to move toward each other. When the detection system detects that the detected object is a soybean plant, the control system sends a signal to the servo power module. The servo power module controls the operation of the servo drive assembly so that the two comb plates are synchronously unfolded when passing through the soybean plant to perform the seedling avoidance operation.

[0009] In a further embodiment, the material of the contoured elastic comb teeth includes soft stainless steel, and there are twelve contoured elastic comb teeth in total, and six contoured elastic comb teeth are provided under each comb plate;

[0010] The shape of the profiling elastic comb teeth imitates the shape of a soybean plant, and the profiling is performed according to the height positions of the stalk part and the crown part above the cotyledon of the soybean plant.

[0011] In a further embodiment, the servo drive assembly includes a servo driver and a servo motor mounted on the frame, a drive shaft of the servo motor is connected to one end of a main shaft, and a disk is connected to the other end of the main shaft;

[0012] The two comb plates are symmetrically arranged below the disc, and a connecting rod is connected between each comb plate and the disc. A rotating shaft is installed at both ends of the connecting rod, and the two ends are rotatably connected to the comb plate and the disc respectively through the two rotating shafts.

[0013] A guide rail is installed on one side of the frame facing the comb plate, a slider is slidably connected to the guide rail, and the slider and the comb plate are connected via a fixing rod.

[0014] In a further embodiment, two laser ranging sensors are provided on the frame, and the two laser ranging sensors are provided on the frame at the upper end and the lower end at the same vertical position.

[0015] In a further embodiment, the connection module is used to control the operation of the connection component, the connection component includes a hardware device for transmitting signals, a motor power line and a motor encoding line, the PLC controller is connected to the servo drive through the hardware device, and the servo drive is connected to the servo motor through the motor power line and the motor encoding line.

[0016] In a further embodiment, the PLC controller converts the distance data collected by the laser distance measuring sensor into diameter terms, and the range of the laser distance measuring sensor is 120 mm-280 mm;

[0017] The PLC controller reads the current distance data of the laser ranging sensor every 10ms, and then determines the diameter of the object being measured by observing the number of points that continuously meet the range of 120mm-280mm, that is, the minimum range and maximum range of the laser ranging sensor, and the difference between the front and rear distance data is no more than 10mm from the current distance data;

[0018] When the distance data between the laser ranging sensor and the measured object is within the range of one of the laser ranging sensors, and the difference between the distance data between the other laser ranging sensor and the measured object and the current distance data is within 10 mm, the current data distance is 1; otherwise, the distance is 0. The calculation formula is as follows:

[0019]

[0020] Wherein, d represents the distance between the laser ranging sensor and the object being measured; d0 represents the distance between the next laser ranging sensor and the object being measured; d min Represents the minimum range of the laser ranging sensor; d max Represents the maximum range of the laser ranging sensor.

[0021] In a further embodiment, the diameter condition is that when the distance data read by the PLC controller from the laser ranging sensor is within the range of the laser ranging sensor, it is recorded as 1;

[0022] If the distance data collected in the next 10ms is within the range of the laser ranging sensor, the recorded value is increased by 1, that is, 2;

[0023] If it is not within the range of the laser ranging sensor, the recorded value is cleared to zero. When the condition is met next time, the recorded value is reset to 1. The calculation formula for the diameter condition is as follows:

[0024] D c =vt

[0025]

[0026]

[0027] Among them, D c represents the theoretical diameter of the object being measured; v represents the running speed; t represents the time from the start of detection of the object being measured to the end; x1 represents the distance data recorded in the current 10ms; x2 represents the distance data recorded in the next 10ms; d min Represents the minimum range of the laser ranging sensor; d max represents the maximum range of the laser ranging sensor; c represents the time recording value of the measured object.

[0028] In a further embodiment, the PLC controller converts the distance data collected by the laser ranging sensor into a height condition. When the value recorded by the laser ranging sensor at the lower end is greater than or equal to 2, the PLC controller observes whether the laser ranging sensor at the upper end has distance data within the range. Since the stems of soybean plants are relatively straight, the threshold is set to 9 mm.

[0029] When the laser ranging sensor at the upper end detects distance data within the measuring range, within 9 mm of operation, the laser ranging sensor at the lower end records a value greater than or equal to 2; or when the laser ranging sensor at the lower end records a value greater than or equal to 2, within 9 mm of operation, the laser ranging sensor at the upper end detects distance data within the measuring range. Both of the above situations can meet the height condition. The diameter condition calculation formula is as follows:

[0030]

[0031] Among them, d h上 Represents the distance data between the upper laser ranging sensor and the measured object; x h上 Represents the position of the upper laser ranging sensor; d h下 Represents the distance data between the laser ranging sensor below and the object being measured; x h下 Represents the position of the laser ranging sensor below.

[0032] In a further embodiment, the PLC controller converts the distance data collected by the laser ranging sensor into a spacing condition. The spacing condition is that when the current measured object is determined to be a soybean plant, a 10 cm spacing condition is enabled, and the threshold is 3 cm, that is, plants that meet the diameter condition and height condition within 7-13 cm behind the current soybean plant are used. The spacing condition calculation formula is as follows:

[0033] f(x l )=|x l前 -x l后 |,7≤x l ≤13

[0034] Among them, x l前 represents the position of the previous soybean plant; x l后 Represents the position of the next soybean plant.

[0035] A control method for controlling the reciprocating soybean inter-row seedling avoidance and weeding device, the method comprising the following steps:

[0036] Step 1: When the weeding mechanism moves, the laser ranging sensor detects the object in front and transmits the signal to the control system;

[0037] Step 2: The PLC controller identifies the object to be tested according to the program of the soybean recognition model;

[0038] Step 3: If the object being detected is a soybean plant, the servo power module controls the servo drive assembly to operate, and the two comb plates are synchronously unfolded to perform the seedling avoidance action;

[0039] Step 4: If the object being measured is not a soybean plant that can be identified by the soybean identification model program, the servo power module controls the servo drive component to operate, and the two comb plates are closed synchronously to perform weeding operations.

[0040] The present invention has the following beneficial effects: a laser rangefinder sensor acquires distance data of the measured object, and a PLC controller determines whether it is a soybean plant based on a programmed soybean recognition model program. The comb teeth below the weeding mechanism are arranged side by side and are contoured. This effectively prevents environmental factors such as light and shadow from causing a decrease in recognition rate, enabling real-time detection and weeding at a low cost. The side-by-side elastic contoured comb teeth effectively increase the contact area with the soil, thereby improving the weeding rate. The elastic contoured comb teeth, due to their inherent material and shape, only distort soybean stems and leaves if accidentally contacted, without damaging them. Furthermore, the contoured comb teeth significantly reduce the likelihood of contact with soybean plants, resolving the problem of high seedling injury rates during inter-plant weeding. The device has high economic and social value and promising application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a front structural schematic diagram of the present invention.

[0042] Figure 2 It is a side structural schematic diagram of the weeding mechanism of the present invention.

[0043] Figure 3 It is a schematic diagram of the top view of the contoured elastic comb teeth of the present invention.

[0044] Figure 4 It is a schematic top view of the structure of the disc, connecting rod and comb plate of the present invention in the expanded and closed states.

[0045] Figure 5 It is a seedling avoidance control flow chart of the present invention.

[0046] Figure 6 This is the original image of distance data collected by the laser ranging sensor.

[0047] Figure 7 This is a diagram of the distance data collected by the sensor read by the PLC controller without filtering.

[0048] Figure 8 It is an algorithm that processes the distance data collected by the PLC controller.

[0049] Figure 9 This is a distance data graph of the laser ranging sensor located at the upper end position tested at a running speed of 0.3m / s.

[0050] Figure 10 This is a distance data diagram of the laser ranging sensor located at the lower end position tested at a running speed of 0.3m / s.

[0051] The accompanying drawings are marked as follows: 1. servo motor; 2. laser ranging sensor; 3. fixing bracket; 4. motor power line; 5. motor encoding line; 6. PLC electric control box; 7. frame; 8. main shaft; 9. disc; 10. connecting rod; 11. guide rail; 12. fixing rod; 13. comb plate; 14. contoured elastic comb. DETAILED DESCRIPTION

[0052] In the following description, numerous specific details are provided to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without one or more of these details. In other instances, certain technical features well known in the art are not described to avoid confusion with the present invention.

[0053] The present invention will be further described in detail below with reference to the accompanying drawings.

[0054] Reference Figure 1-10, a reciprocating soybean inter-row seedling avoidance and weeding device and control method disclosed in the present invention, including a detection system, a control system and a weeding mechanism, the detection system includes a laser ranging sensor 2, the laser ranging sensor 2 is arranged on the weeding mechanism and is used to measure the distance data between the laser ranging sensor 2 and the measured object, the measured object including soybean plants and weeds; the control system reads the distance data collected by the laser ranging sensor 2 in real time and identifies the measured object, the control system includes a PLC controller, an analog input module, a connection module and a servo power module, the control system includes a CPU, an electric The control system comprises a circuit, a touch screen and control software. The hardware of the control system is arranged in a PLC control box, which is arranged on a frame 7. The PLC controller writes a soybean recognition model program according to the diameter and height of the soybean plant and the planting distance between the soybean plants. The soybean recognition model program is established based on three conditions: the diameter and height difference between the soybean plant and the weeds, and the planting distance between the soybean plants. The diameter is calculated by collecting frequency and distance data. The plant distance is specified at the time of planting. The height is the height of the soybean plant during the mechanical weeding period. At this time, the soybean plants are basically around 25 cm. In the field, the diameter of the soybean plant is different from that of the weeds, which can be used to distinguish the soybean plants. When the diameter of the soybean plant is similar to that of the weeds, the weeds are generally short and can be distinguished by their height. Sometimes the height of individual weeds is higher, and in this case, they can be distinguished according to the spacing between the soybean plants. Through the above three conditions, the recognition rate of the soybean recognition model can reach more than 95%. The laser ranging sensor 2 transmits the generated analog signal to the PLC controller through the analog input module, and the PLC controller is connected to the servo power module through the connection module; the weeding mechanism It includes a frame 7 and a servo drive component and a weeding component arranged on the frame 7. The weeding component includes two comb plates 13 and contoured elastic comb teeth 14. A plurality of contoured elastic comb teeth 14 are welded under each comb plate 13 and arranged side by side at equal intervals. The servo drive component drives the two comb plates 13 to move toward each other. When the detection system detects that the object to be detected is a soybean plant, the control system sends a signal to the servo power module. The servo power module controls the operation of the servo drive component so that the two comb plates 13 are synchronously unfolded when passing through the soybean plant to perform the seedling avoidance operation.

[0055] The material of the profiling elastic comb teeth 14 includes soft stainless steel with a certain elasticity. There are twelve profiling elastic comb teeth 14 in total, and six profiling elastic comb teeth 14 are provided under each comb plate 13; the shape of the profiling elastic comb teeth 14 imitates the shape of the soybean plant, and is profiled according to the height position of the stem part and the cotyledon and the crown part above the soybean plant. The purpose is to protect the stem and leaves of the soybean plant as much as possible when the soybean seedling recognition model does not recognize the soybean plant. According to investigations and studies, the height of the cotyledons of soybean plants from the soil surface during the mechanical weeding period is basically about 8 cm. Therefore, the bottom of the profiling elastic comb teeth 14 only needs to be profiled at a position close to the height of the cotyledons. Since the cotyledons will fall off immediately, the damage to the cotyledons is not included in the seedling injury rate. The cotyledons are the two lowest leaves of the soybean plant.

[0056] The servo drive assembly includes a servo driver and a servo motor 1 installed on the frame 7, the drive shaft of the servo motor 1 is connected to one end of the main shaft 8, and the other end of the main shaft 8 is connected to the disc 9; the two comb plates 13 are symmetrically arranged below the disc 9, and a connecting rod 10 is connected between each comb plate 13 and the disc 9, and both ends of the connecting rod 10 are installed with a rotating shaft, and its two ends are respectively connected to the comb plate 13 and the disc 9 for rotation through the two rotating shafts; the frame 7 is installed with a guide rail 11 on the side facing the comb plate 13, and a slider is slidably connected to the guide rail 11, and the slider and the comb plate 13 are connected. They are connected by a fixed rod 12. When the main shaft 8 is driven by the servo motor 1 to rotate, the main shaft 8 drives the disc 9 to rotate, and the disc 9 drives the connecting rod 10 to swing. Since the connecting rod 10 rotates with the disc 9 and the comb plate 13 respectively through the rotating shaft, and the guide rail 11 is fixed under the frame 7, the fixed rod 12 is welded to the slider and the comb plate 13. The comb plate 13 is restricted in its moving direction under the joint action of the connecting rod 10 and the fixed rod 12, and can only perform reciprocating motion in the horizontal direction. When the disc 9 rotates clockwise, the two comb plates 13 move away from each other and expand to perform the seedling avoidance operation. When the disc 9 rotates counterclockwise, the two comb plates 13 approach each other and close to perform the weeding operation.

[0057] Two laser distance measuring sensors 2 are provided on the frame 7 . The two laser distance measuring sensors 2 are provided on the frame 7 at the upper end and the lower end of the same vertical position, and the acquisition frequency thereof is adjustable.

[0058] The connection module is used to control the operation of the connection component, which includes a hardware device for transmitting signals, a motor power line 4 and a motor encoding line 5. The PLC controller is connected to the servo driver through the hardware device, and the servo driver is connected to the servo motor 1 through the motor power line 4 and the motor encoding line 5. The hardware device includes an RS485 conversion line. The PLC controller is connected to the RS485 communication interface through one end of the RS485 conversion line, and the other end is connected to the RS485 network port of the servo driver.

[0059] The PLC controller converts the distance data collected by the laser ranging sensor 2 into a diameter condition, and the range of the laser ranging sensor 2 is 120mm-280mm; the PLC controller reads the current distance data of the laser ranging sensor 2 every 10ms, and then observes the number of points that continuously meet the range of 120mm-280mm, that is, the minimum range and maximum range of the laser ranging sensor 2, and the difference between the front and rear distance data is no more than 10mm from the current distance data, to determine the diameter of the object being measured; when the distance data between the laser ranging sensor 2 and the object being measured is within the range of one of the laser ranging sensors 2, and the difference between the distance data between the other laser ranging sensor 2 and the object being measured and the current distance data is within 10mm, that is, the current data distance is 1, otherwise the distance is 0. After algorithm processing, the derived data is as follows Figure 8As shown, objects of different diameters can be distinguished based on data that continuously records as 1. This serves as a basis for programming the diameter condition in the PLC controller. For example, at a speed of 0.3 m / s, reading a 5 mm diameter object every 10 ms will produce two consecutive points with distance data between 120 mm and 280 mm. However, reading a 3 mm diameter object every 10 ms will only produce one point with distance data between 120 mm and 280 mm, with the remaining points exceeding the measuring range. Therefore, based on the current operating speed, objects of different diameters can be distinguished based on consecutive points with distance data within the range of 120 mm to 280 mm. At the three-leaf stage, soybean plants typically have a diameter between 4 and 5 mm, while weeds have a diameter of around 3 mm, generally less than 3 mm. Therefore, taking a speed of 0.3m / s as an example, when the laser ranging sensor 2 identifies a soybean plant, the soybean plant will be within the sensor's range. At this time, when the soybean plant is detected by the laser ranging sensor 2, there will be two consecutive points in the PLC controller, while when the weeds are detected, there will be only one point. The laser ranging sensor 2 reads the distance data in real time, and its range is 120mm-280mm. When the distance between the measured object and the laser ranging sensor 2 is less than 120mm or greater than 280mm, it will exceed the range. The laser ranging sensor 2 outputs an analog current to the PLC controller, and is calibrated according to the input analog value and the actual distance. After the calibration is completed, the functional relationship between the analog value and the actual distance is fitted and programmed in the PLC controller program. The distance data detected by the laser ranging sensor 2 is exported from the PLC controller as follows: Figure 6 As shown in the figure, we can only judge the number of objects from the figure, but cannot reflect the diameter of the measured object. So we set the PLC controller to no filtering mode and export the distance data as follows Figure 7 As shown in the figure, it can be seen that the diameters of different objects are different. At this time, the number of noise points has obviously decreased, and the diameter of the object being measured can be reflected from the number of points. Then perform algorithm processing. Figure 8 is based on Figure 7 The algorithm processing formula is as follows:

[0060]

[0061] Wherein, d represents the distance between the laser ranging sensor 2 and the object being measured; d0 represents the distance between the next laser ranging sensor 2 and the object being measured; d min Represents the minimum range of the laser ranging sensor 2; d max Represents the maximum range of the laser ranging sensor 2.

[0062] The diameter condition is that when the distance data read by the PLC controller from the laser ranging sensor 2 is within the range of the laser ranging sensor 2, it is recorded as 1; if the distance data collected in the next 10ms is within the range of the laser ranging sensor 2, the recorded value is increased by 1, that is, 2; if it is not within the range of the laser ranging sensor 2, the recorded value is cleared, and the recorded value is reset to 1 when the condition is met next time. Taking a speed of 0.3m / s as an example, according to the collection time and speed, it is calculated that when the diameter is less than 3mm, the record is 1; when the diameter is 3-6mm, the record value is 2. Therefore, for soybean plants with a diameter of 4-5mm, the recorded value will be greater than or equal to 2, while the recorded value of weeds with a diameter of less than 3mm is 1. That is, when the recorded value is 0 or 1, it indicates that no object is detected or weeds may be detected; when the recorded value is greater than or equal to 2, the stems of soybean plants may be detected. The calculation formula for the diameter condition is as follows:

[0063] D c =vt

[0064]

[0065]

[0066] Among them, D c represents the theoretical diameter of the object being measured; v represents the running speed; t represents the time from the start of detection of the object being measured to the end; x1 represents the distance data recorded in the current 10ms; x2 represents the distance data recorded in the next 10ms; d min Represents the minimum range of the laser ranging sensor; d max represents the maximum range of the laser ranging sensor; c represents the time recording value of the measured object.

[0067] The PLC controller converts the distance data collected by the laser ranging sensor 2 into a height condition. When the value recorded by the laser ranging sensor 2 at the lower end is greater than or equal to 2, the laser ranging sensor 2 at the upper end is observed to see whether it has distance data within the measuring range. Since the soybean plant stems are relatively straight, the threshold is set to 9 mm. When the laser ranging sensor 2 at the upper end detects distance data within the measuring range, the value recorded by the laser ranging sensor 2 at the lower end is greater than or equal to 2 within the running 9 mm. Or when the laser ranging sensor 2 at the lower end records a value greater than or equal to 2, the laser ranging sensor 2 at the upper end detects distance data within the measuring range within the running 9 mm. Both of the above situations can meet the height condition. The diameter condition calculation formula is as follows:

[0068]

[0069] Among them, d h上Represents the distance data between the upper laser ranging sensor 2 and the measured object; x h上 Represents the position of the upper laser ranging sensor 2; d h下 Represents the distance data between the laser ranging sensor 2 below and the object being measured; x h下 Represents the position of the laser ranging sensor 2 below.

[0070] The PLC controller converts the distance data collected by the laser ranging sensor 2 into a spacing condition. The spacing condition is that when the current object being measured is determined to be a soybean plant, a spacing condition of 10 cm will be enabled, and the threshold is 3 cm, that is, plants that meet the diameter and height conditions within 7-13 cm behind the current soybean plant are selected. The spacing condition calculation formula is as follows:

[0071] f(x l )=|x l前 -x l后 |,7≤x l ≤13

[0072] Among them, x l前 represents the position of the previous soybean plant; x l后 Represents the position of the next soybean plant.

[0073] A control method for controlling the reciprocating soybean inter-plant seedling avoidance and weeding device, the method comprising the following steps:

[0074] Step 1: The frame 7 is fixedly connected to the fixed frame 3, and then the fixed frame 3 is hung on the mobile platform. The upper and lower laser distance sensors 2 are arranged so that the laser distance sensor 2 is placed on one side of the object to be measured and the distance between the laser distance sensor 2 and the object to be measured is about 20 cm. The lines between the laser distance sensor 2 and the PLC controller and between the PLC controller and the servo driver are connected. The PLC electrical control box 6 is closed. When the weeding mechanism moves, the laser distance sensor 2 detects the object to be measured in front and transmits the signal to the control system.

[0075] Step 2: The PLC controller identifies the object to be measured according to the program of the soybean recognition model. The system is powered on, the software and hardware are initialized, and the control system reads the distance data collected by the laser ranging sensor 2 in real time. The PLC controller uses the programmed soybean recognition model. At this time, if both aspects are met, the soybean recognition model can be passed, that is, the object to be measured is determined to be a soybean plant.

[0076] First, check whether the value recorded by the PLC controller is greater than or equal to 2. After the diameter condition is met, check whether the position difference between the upper and lower laser distance sensors 2 is within the 9mm threshold at the same height of the object. After the height adjustment is met, check whether the distance between the object and the previous soybean plant is within 10cm, with a threshold of 3cm. If all the above conditions are met, it is determined to be a soybean plant.

[0077] Secondly, since the diameter of a soybean plant can be around 3mm, a recorded value of 1 or greater is retained. If the height and spacing conditions are met, it is also considered a soybean plant, as weeds are generally shorter. Using the soybean recognition model, the recognition rate for soybean plants can reach over 95%.

[0078] Step 3: If the object to be measured is a soybean plant, the PLC controller calculates the time based on the current driving speed of the mobile platform and the horizontal distance between the sensor and the weeding mechanism, and then sends a command to the servo driver. The servo driver causes the servo motor 1 to rotate synchronously, so that the two comb plates 13 in the weeding mechanism are simultaneously unfolded, and the seedling avoidance action is completed synchronously;

[0079] Step 4: When the soybean plant is under the weeding mechanism, the servo motor 1 maintains the rotation angle, so that the comb plate 13 remains in the expanded state; if the object being measured is not a soybean plant that can be identified by the soybean recognition model program, after the soybean plant passes through the weeding mechanism, the servo motor 1 rotates again to close the comb plate 13 and continue the weeding operation; the contoured elastic comb teeth 14 in the weeding mechanism complete the seedling avoidance and weeding operations by reciprocating expansion and closing until the weeding operation is completed.

[0080] The above calculation method was used to test 4 soybean plants at a speed of 0.3m / s to observe the recognition effect of the soybean recognition model on soybean plants and the damage to the seedlings of the weeding mechanism. The distance data recorded at a speed of 0.3m / s is as follows: Figure 9 and Figure 10As shown. Since the upper laser ranging sensor 2 only needs to determine whether an object is detected, the derived distance data does not require algorithmic processing. The distance data collected by the lower laser ranging sensor 2 is processed by the algorithm. The number of points where the distance data is within the range and the difference between two adjacent points is less than or equal to 10 is recorded as 1; the number of points outside the range is recorded as 0. The upper figure is the distance data collected by the upper laser ranging sensor 2, and the lower figure is the distance data collected by the lower laser ranging sensor 2. It can be seen from the lower figure that the number of points for each identified plant is 2, that is, the diameter of the measured object is greater than 3mm, which meets the diameter condition. From the upper and lower figures, it can be seen that the plants are at the same height. The positions of the upper and lower laser ranging sensors 2 when detecting data are within the threshold, and the distance data of the upper laser ranging sensor 2 is within the range, which meets the height condition. Finally, from the lower figure, it can be seen that the difference in plant spacing between plants is basically consistent and within the threshold, which meets the spacing condition. In summary, the soybean recognition model of the present invention can basically identify soybean planting, indicating that the recognition method is feasible.

[0081] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

[0082] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the scope of protection of the present invention.

Claims

1. A reciprocating soybean weeding and weeding device, characterized by: The system comprises a detection system, a control system and a weeding mechanism, wherein the detection system comprises a laser distance sensor, and the laser distance sensor is arranged on the weeding mechanism to measure the distance data between the laser distance sensor and the measured object, wherein the measured object comprises soybean plants and weeds; The control system reads the distance data detected by the laser ranging sensor in real time. The control system includes a PLC controller, an analog input module, a connection module, and a servo power module. The PLC controller writes a soybean recognition model program based on the diameter and height of soybean plants and the distance between soybean plants. The laser ranging sensor transmits the generated analog signal to the PLC controller through the analog input module. The PLC controller is connected to the servo power module through the connection module. The weeding mechanism includes a frame and a servo drive assembly and a weeding assembly arranged on the frame, the weeding assembly includes two comb plates and contoured elastic comb teeth, a plurality of contoured elastic comb teeth are welded below each of the comb plates and arranged side by side at equal intervals, the shape of the contoured elastic comb teeth is contoured according to the height position of the stem part and the cotyledon and the crown part above the soybean plant, the servo drive assembly drives the two comb plates to move toward each other, when the detection system detects that the detected object is a soybean plant, the control system sends a signal to the servo power module, the servo power module controls the operation of the servo drive assembly so that the two comb plates are synchronously unfolded when passing through the soybean plant to perform the seedling avoidance operation; Two laser distance measuring sensors are provided on the frame, and the two laser distance measuring sensors are arranged on the frame at the upper end and the lower end of the same vertical position.

2. The reciprocating soybean inter-row weeding device according to claim 1, characterized in that: The material of the contoured elastic comb teeth includes soft stainless steel. There are twelve contoured elastic comb teeth in total, and six contoured elastic comb teeth are provided under each comb plate. The shape of the profiling elastic comb teeth imitates the shape of a soybean plant, and the profiling is performed according to the height positions of the stalk part and the crown part above the cotyledon of the soybean plant.

3. The reciprocating soybean inter-row weeding device according to claim 1, characterized in that: The servo drive assembly includes a servo driver and a servo motor mounted on the frame, wherein the drive shaft of the servo motor is connected to one end of the main shaft, and the other end of the main shaft is connected to a disc; The two comb plates are symmetrically arranged below the disc, and a connecting rod is connected between each comb plate and the disc. A rotating shaft is installed at both ends of the connecting rod, and the two ends are rotatably connected to the comb plate and the disc respectively through the two rotating shafts. A guide rail is installed on one side of the frame facing the comb plate, a slider is slidably connected to the guide rail, and the slider and the comb plate are connected via a fixing rod.

4. The reciprocating soybean inter-row weeding device according to claim 3, characterized in that: The connection module is used to control the operation of the connection component, which includes a hardware device for transmitting signals, a motor power line and a motor encoding line. The PLC controller is connected to the servo drive through the hardware device, and the servo drive is connected to the servo motor through the motor power line and the motor encoding line.

5. The reciprocating soybean inter-row weeding device according to claim 1, characterized in that: The PLC controller converts the distance data collected by the laser distance measuring sensor into diameter conditions, and the range of the laser distance measuring sensor is 120mm-280mm; The PLC controller reads the current distance data of the laser ranging sensor every 10ms, and then determines the diameter of the object being measured by observing the number of points that continuously meet the range of 120mm-280mm, that is, the minimum and maximum ranges of the laser ranging sensor, and the difference between the front and rear distance data is not much less than 10mm from the current distance data; When the distance data between the laser ranging sensor and the measured object is within the range of one of the laser ranging sensors, and the difference between the distance data between the other laser ranging sensor and the measured object and the current distance data is within 10 mm, the current data distance is 1; otherwise, the distance is 0. The calculation formula is as follows: Wherein, d represents the distance between the laser ranging sensor and the object being measured; d0 represents the distance between the next laser ranging sensor and the object being measured; d min Represents the minimum range of the laser ranging sensor; d max Represents the maximum range of the laser ranging sensor.

6. The reciprocating soybean inter-row weeding device according to claim 5, characterized in that: The diameter condition is that when the distance data read by the PLC controller from the laser ranging sensor is within the range of the laser ranging sensor, it is recorded as 1; If the distance data collected in the next 10ms is within the range of the laser ranging sensor, the recorded value is increased by 1, that is, 2; If it is not within the range of the laser ranging sensor, the recorded value is cleared to zero. When the condition is met next time, the recorded value is reset to 1. The calculation formula for the diameter condition is as follows: D c =vt Among them, D c represents the theoretical diameter of the object being measured; v represents the running speed; t represents the time from the start of detection of the object being measured to the end; x1 represents the distance data recorded in the current 10ms; x2 represents the distance data recorded in the next 10ms; d min Represents the minimum range of the laser ranging sensor; d max represents the maximum range of the laser ranging sensor; c represents the time recording value of the measured object.

7. The reciprocating soybean inter-row weeding device according to claim 6, characterized in that: The PLC controller converts the distance data collected by the laser ranging sensor into a height condition. When the value recorded by the laser ranging sensor at the lower end is greater than or equal to 2, the PLC controller observes whether the laser ranging sensor at the upper end has distance data within the range. Since the soybean plant stems are relatively straight, the threshold is set to 9 mm. When the laser ranging sensor at the upper end detects distance data within the measuring range, within 9 mm of operation, the laser ranging sensor at the lower end records a value greater than or equal to 2; or when the laser ranging sensor at the lower end records a value greater than or equal to 2, within 9 mm of operation, the laser ranging sensor at the upper end detects distance data within the measuring range. Both of the above situations can meet the height condition. The diameter condition calculation formula is as follows: Among them, d h上 Represents the distance data between the upper laser ranging sensor and the object being measured; x h上 Represents the position of the upper laser ranging sensor; d h下 Represents the distance data between the laser ranging sensor below and the object being measured; x h下 Represents the position of the laser ranging sensor below.

8. The reciprocating soybean inter-row weeding device according to claim 7, characterized in that: The PLC controller converts the distance data collected by the laser ranging sensor into a spacing condition. The spacing condition is that when the current object being measured is determined to be a soybean plant, a 10 cm spacing condition is enabled, and the threshold is 3 cm, that is, plants that meet the diameter and height conditions within 7-13 cm behind the current soybean plant are selected. The spacing condition calculation formula is as follows: f(x l )=|x l前 -x l后 |,7≤x l ≤13 Among them, x l前 represents the position of the previous soybean plant; x l后 Represents the position of the next soybean plant.

9. A method for controlling the reciprocating soybean inter-row weeding device according to claim 1, characterized in that: The method comprises the following steps: Step 1: When the weeding mechanism moves, the laser ranging sensor detects the object in front and transmits the signal to the control system; Step 2: The PLC controller identifies the object to be tested according to the program of the soybean recognition model; Step 3: If the object being detected is a soybean plant, the servo power module controls the servo drive assembly to operate, and the two comb plates are synchronously unfolded to perform the seedling avoidance action; Step 4: If the object being measured is not a soybean plant that can be identified by the soybean identification model program, the servo power module controls the servo drive component to operate, and the two comb plates are closed synchronously to perform weeding operations.

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