Soil crushing rate map creation method and creation device

Abstract

To provide a technology for creating a soil crushing rate map.SOLUTION: A soil crushing rate map creation device (10) comprises: a calculation part (14) that calculates a soil crushing rate in a soil image capturing an image of soil in a work object area by referencing a predetermined feature value of clods in the soil image; and a map creation part (15) that maps the calculated soil crushing rate to a position corresponding to a space in which the soil image is captured on a map representing the work object area.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method and device for creating a soil crushing rate map. [Background technology]

[0002] Compared to upland fields, paddy fields have poorer soil crushing properties, and much time is spent on tilling to achieve a soil crushing rate suitable for sowing soybeans and wheat. If we could implement tilling methods appropriate to the field conditions, such as speeding up tilling in soils with good crushing properties and plowing carefully in soils with poor crushing properties, we could reduce the overall tilling time. However, currently, measuring soil crushing rates requires time and manpower, and it is not possible to grasp the soil crushing status of the entire field. Therefore, if it were possible to easily create a soil crushing rate map that would allow us to grasp the soil crushing status of the entire field at a glance, it would be possible to significantly streamline and reduce the labor required for tilling.

[0003] The crushing rate for creating a crushing rate map is generally calculated by the sieving method, in which soil is collected after plowing, and the soil clods are manually separated into particle sizes using a sieve, and the weight of each clod is measured, and the crushing rate is calculated as the weight percentage of soil clods with a diameter of 20 mm or more.

[0004] Also, methods described in Non-Patent Document 1 and Patent Document 1 are known as methods for evaluating soil conditions by analyzing images of the soil surface. Non-Patent Document 1 describes a technique for estimating the unevenness of the soil surface from images obtained from a camera attached to a tillage implement. Patent Document 1 describes a technique for estimating the depth of furrows formed in the soil by the tillage implement from images obtained from a camera attached to the tillage implement. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-47256 [Non-patent literature]

[0006] [Non-Patent Document 1] Marinello et al., Precision Agric(2015), 16:601-612 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the sieving method requires time and effort to measure the soil crushing rate point by point by hand, making it difficult to create a soil crushing rate map for the entire field. Furthermore, the techniques described in Non-Patent Document 1 and Patent Document 1 only evaluate the unevenness of the soil surface and the grooves formed in the soil, and do not estimate the soil crushing rate, so they cannot be used to create a soil crushing rate map.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to realize a technology for creating a soil crushing rate map of a farm field. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, a method for creating a soil crushing rate map according to one aspect of the present invention includes a soil crushing rate calculation step of calculating the soil crushing rate of the soil in a soil image obtained by photographing the soil of a work area by referring to predetermined feature values ​​of soil masses in the soil image; and a mapping step of mapping the soil crushing rate on a map representing the work area to a position corresponding to the space where the soil image was photographed. This includes a step of creating a backup.

[0010] A soil crushing rate map creation device according to one embodiment of the present invention includes a soil crushing rate calculation unit that calculates the soil crushing rate of the soil in a soil image by referring to predetermined feature values ​​of soil masses in a soil image of the soil in a work area, and a map creation unit that maps the soil crushing rate to a position on a map representing the work area corresponding to the space in which the soil image was taken.

[0011] The soil crushing rate map creation device according to each aspect of the present invention may be realized by a computer. In this case, the control program of the soil crushing rate map creation device, which causes the computer to operate as each part (software element) of the device, thereby realizing the device on a computer, and the computer-readable recording medium on which it is recorded, also fall within the scope of the present invention. [Effects of the Invention]

[0012] According to one aspect of the present invention, a technique for creating a soil crushing rate map of a farm field can be realized. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram showing an example of a configuration of a main part of a soil crushing rate map creation system including a soil crushing rate map creation device according to an embodiment of the present invention. [Figure 2] 1 is a diagram showing an example of a soil crushing rate map created by a soil crushing rate map creation device according to an embodiment of the present invention; [Figure 3] 1 is a flowchart showing a flow of a soil crushing rate map creation process performed by a soil crushing rate map creation device according to an embodiment of the present invention. [Figure 4] 1 is a graph showing the results of a comparison between an estimated soil crushing rate and an actually measured soil crushing rate in an example. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Method and device for creating a soil crushing rate map) A method for creating a soil crushing rate map (soil crushing rate map creation method) according to one embodiment of the present invention will be described in detail below. FIG. 1 is a block diagram showing an example of the main configuration of a soil crushing rate map creation system 100 including an embodiment of a soil crushing rate map creation device 10 that executes the soil crushing rate map creation method according to one embodiment of the present invention. As shown in FIG. 1, the soil crushing rate map creation system 100 includes the soil crushing rate map creation device 10. The soil crushing rate map creation system 100 may further include a photographing device 20 and an input device 30. The soil crushing rate map creation system 100 may further include an output device 40 and a storage device 50. The soil crushing rate map creation device 10 is connected to the photographing device 20, the input device 30, the output device 40, and the storage device 50 so as to be able to communicate data with them. The soil crushing rate map creation device 10, the photographing device 20, the input device 30, the output device 40, and the storage device 50 may each be independent devices, or these devices may be integrated into a single device.

[0015] The image capturing device 20 may be a camera that captures images of the soil in the work area. The camera may be, for example, a visible light camera such as a digital camera or a smartphone camera. The camera may also be an inexpensive, readily available compact digital camera or a surveillance camera. A visible light camera includes an optical system such as a lens, a light detection element, and the like, and generates visible light image data by detecting light from a subject.

[0016] The image capturing device 20 may be attached to the tip of a drone or a crane to capture images of the soil in the work area from above. The camera 20 may be mounted on a work machine that performs work. One example of a work machine to which the camera 20 is attached is an agricultural work machine such as a tiller that performs tilling work. The camera 20 may be installed so as to take an overhead view from above the working unit that crushes the soil as the agricultural work machine moves forward. The working unit is the part that is inserted into the soil and performs the work of tilling (crushing) the soil.

[0017] The photographing device 20 outputs at least one of the date and time when the image was taken and location information to the soil crushing rate map creation device 10 along with an image of the soil in the work area. If the photographing device 20 is installed on an agricultural work machine, the location information when the image was taken may be obtained by identifying the position of the agricultural work machine at the date and time when the image was taken based on the movement trajectory of the agricultural work machine. Therefore, it is preferable that the photographing device 20 has a time correction function with respect to standard time. It is also preferable that the photographing device 20 be controlled to take soil images at regular time intervals or at a regular distance.

[0018] The input device 30 accepts input operations by a user to the soil crushing ratio map creation system 100. As an example, the input device 30 accepts input of data used to create a soil crushing ratio map in the soil crushing ratio map creation device 10. The input device 30 outputs the accepted data to the soil crushing ratio map creation device 10 or stores it in the storage device 50.

[0019] As an example, the output device 40 outputs the soil crushing rate map created by the soil crushing rate map creation device 10. The manner of output by the output device 40 is not particularly limited. The output device 40 may be, for example, a display device that displays the soil crushing rate map as an image, a real-time display device of the crushing rate calculated from captured images, or a printing device that prints the soil crushing rate map. The output device 40 may also be a display of a mobile device such as a smartphone that displays the soil crushing rate map created by the soil crushing rate map creation device 10 and the real-time calculated value of the crushing rate. The soil crushing rate map creation device 10 may also be equipped with such an output device 40. In other words, the soil crushing rate map creation device 10 may also be equipped with an output device that outputs the crushing rate calculated from the captured images in real time. "Real-time output" means that the acquired images are immediately processed to calculate and output the crushing rate. By providing an output device that outputs the soil crushing rate in real time, the operator of the agricultural machine or the work planner can recognize the soil crushing rate while working, and can therefore adjust the way the work is being carried out in real time.

[0020] The storage device 50 stores programs and data used in the soil crushing ratio map creation system 100. As an example, the storage device 50 stores various data input via the input device 30. As an example, the storage device 50 also stores the soil crushing ratio map created by the soil crushing ratio map creation device 10, data used for the creation, etc. The storage device 50 may also have a database on the cloud or a server that stores various data.

[0021] The soil crushing rate map creation device 10 is an information processing device that creates a crushing rate map showing the soil condition of the entire field, which is used to reduce the labor required for plowing. The soil crushing rate map creation device 10 includes a control unit 11. The control unit 11 controls each part of the soil crushing rate map creation device 10 and is realized, for example, by a processor and memory. In this example, the processor accesses a storage device (not shown), loads a program (not shown) stored in the storage device into the memory, and executes a series of instructions included in the program. This configures each part of the control unit 11. As each part, the control unit 11 includes a data acquisition unit 12, an image processing unit 13, a calculation unit 14, and a map creation unit 15.

[0022] <Data Acquisition Unit 12> The data acquisition unit 12 acquires soil image data obtained by photographing the soil in the work area. The soil image data acquired by the data acquisition unit 12 may be an image of the soil after work by the work machine, photographed by a photography device 20 installed on a work machine working on the soil in the work area. The data acquisition unit 12 also acquires information related to the date and time of data acquisition and location associated with the soil image data. The data acquisition unit 12 outputs the acquired soil image data to the image processing unit 13. The data acquisition unit 12 also outputs information related to the date and time of acquisition and location of the soil image data to the map creation unit 15.

[0023] <Image processing unit 13> The image processing unit 13 processes the soil image data to create an image suitable for image analysis to calculate the soil crushing rate. As an example, the image processing unit 13 cuts out an area to be analyzed from the soil image data and adjusts the contrast and noise. The image processing unit 13 outputs the processed soil image data to the calculation unit 14.

[0024] When the image capturing device 20 is installed on an agricultural implement, images are captured while the implement is moving and plowing, so images of untilled areas may be included in soil image data captured at the edge of a field where it is difficult for the implement to work. The image processing unit 13 may remove images of such untilled areas from the soil image data and extract the area for image analysis.

[0025] The image processing unit 13 also processes soil image data, including images of soil with at least a portion of the soil being shaded. If the work area for which the soil shattering rate map is to be created is outdoors, the soil may be in shade and in sunlight, and the captured soil image data may have different brightness and color tones. In particular, when the work area is photographed from directly above, the shadow of the camera 20 or the components holding the camera 20 may be superimposed on the soil in the soil image data. If shade or shadow overlaps in the soil image data, this may affect the soil shattering rate calculated based on the image.

[0026] The image processing unit 13 preprocesses the soil image data before calculating the soil crushing rate so that the soil crushing rate can be calculated appropriately even if the soil image data contains shade or overlapping shadows. The image processing unit 13 processes the soil image data by using an image analysis algorithm that takes into account the shade and overlapping shadows that occur in the soil image data. As an example, the image processing unit 13 cuts out an area to be analyzed from the soil image data, then increases the contrast of the image and blurs the image to reduce noise. <Calculation unit 14> The calculation unit 14 derives predetermined feature values ​​of soil clods in soil images captured from the soil in the target work area and calculates the soil crushing rate of the soil in the soil image by referring to the feature values. The feature values ​​of the soil clods are index values ​​indicating the size of the soil clods, such as the area, perimeter, and roughness of the soil clods in the image. The types of feature values ​​are predetermined, and the calculation unit 14 derives the predetermined feature values ​​and calculates the soil crushing rate by referring to the feature values. For example, a relationship between the feature values ​​and the soil crushing rate created in advance may be stored in memory, and the calculation unit 14 can calculate the soil crushing rate by substituting the derived feature values ​​into the relationship. The calculation unit 14 may also include a feature value derivation machine model trained using training data. In this case, the calculation unit 14 can derive feature values ​​using this machine model and calculate the soil crushing rate. Alternatively, the calculation unit 14 may include a soil crushing rate calculation machine model trained using training data including images of soil clods and their soil crushing rates, which directly calculates the soil crushing rate from the images. In this case, the calculation unit 14 can directly calculate the soil crushing rate using such a machine model. The calculation unit 14 outputs the calculated soil crushing rate to the map creation unit 15.

[0027] In the following, as an example, a method in which the calculation unit 14 calculates the soil crushing rate from the area of ​​the soil mass in the image will be described. The calculation unit 14 first classifies the size of the soil clods in the soil image data. As an example, the calculation unit 14 classifies the soil clods using the edges of the soil clods in the soil image data. The soil image data preprocessed by the image processing unit 13 is data from which the effects of shade and overlapping shadows that can occur in the image data have been removed, and therefore the edges of the soil clods are clear, allowing the soil clods to be classified with high accuracy.

[0028] For example, the calculation unit 14 selects necessary pixels based on the edges of soil clods in the soil image data, and separates areas where a predetermined number of pixels are connected. The calculation unit 14 then increases the selected area to match the shape of the soil clod, removes small selected areas as noise, and classifies the remaining selected areas by size.

[0029] The calculation unit 14 calculates the area of ​​each soil clod classified by size, and calculates the area occupied by each size relative to the total area of ​​the soil in the soil image data.The calculation unit 14 then calculates the soil crushing rate from the area occupied by each size, obtained by subtracting the area of ​​soil clods exceeding a predetermined size from the area of ​​the soil in the soil image data.

[0030] Here, the predetermined size can be set appropriately depending on the desired soil crushing property, but as an example, a diameter of 20 mm is used. That is, the calculation unit 14 calculates the soil crushing rate from the occupancy rate (%) of soil clods less than 20 mm in diameter in the image. Specifically, because it is difficult to classify soil clods less than 20 mm in diameter, the calculation unit 14 calculates the area of ​​soil clods with a diameter of 20 mm or more in the image and subtracts this from the total area of ​​the soil in the soil image data to determine the occupancy rate of soil clods less than 20 mm in diameter to the total area (referred to as the "estimated index"). The crushing rate is then calculated by substituting this estimated index into a previously determined relational expression between the actually measured soil crushing rate and the estimated index. The calculation of soil clod diameter, size classification based on soil clod diameter, and other processes can be performed using conventionally known algorithms.

[0031] <Map Creation Department 15> The map creation unit 15 maps the soil crushing rate on a map representing the work area at a position corresponding to the space where the soil image was captured. As an example, the map creation unit 15 maps the soil crushing rate calculated from soil image data captured at a position corresponding to each unit space obtained by dividing the work area into a grid. The map creation unit 15 associates the unit space with the soil crushing rate based on location information associated with the soil image data used to calculate the soil crushing rate. As an example, in the case of soil image data obtained from the imaging device 20 installed on an agricultural implement, the map creation unit 15 maps the soil crushing rate to a position on the map corresponding to the location of the agricultural implement at the date and time the soil image was captured.

[0032] The map creation unit 15 divides the work area into multiple unit spaces, and for each unit space, maps the crushing rate calculated from a soil image taken of the space closest to its center point as the crushing rate for that unit space. The size of the unit space varies depending on the angle of view, shooting interval, number, etc. of the soil image data to be acquired, and is not particularly limited. However, if the image capture device 20 is installed on an agricultural work machine, it may be determined according to the working width of the agricultural work machine. As an example, the unit space may be a 2m x 2m mesh.

[0033] Then, for each such unit space, the map creation unit 15 extracts a soil image of the space closest to its center point, and maps the soil crushing rate calculated from the soil image as the soil crushing rate for that unit space. Even if the space where the soil image was taken does not match the unit space on the map, appropriate mapping is possible by mapping using the center point of the unit space as the reference point. Note that the soil crushing rate may not be calculated for all unit spaces. If the soil crushing rate cannot be calculated for some reason, the soil crushing rate data for that unit space is treated as absent (or zero), and data processing for the next unit space is performed.

[0034] The map creation unit 15 repeats the mapping process until data processing has been completed for all unit spaces, thereby completing a soil crushing rate map such as that shown in Fig. 2. Fig. 2 is a diagram showing an example of a soil crushing rate map created by a soil crushing rate map creation device 10 according to one embodiment of the present invention. The soil crushing rate map shown in Fig. 2 was created by dividing a field of approximately 1.6 ha into unit spaces of 2 m x 2 m. As shown in Fig. 2, by creating a soil crushing rate map that shows the soil crushing rate for each unit space in correspondence with a color scale (gray scale in Fig. 2), the distribution of the soil crushing rate within the work area can be easily grasped.

[0035] (Soil crushing rate map creation process) The soil crushing rate map creation process by the soil crushing rate map creation device 10 will be described with reference to Fig. 3. Fig. 3 is a flowchart showing the flow of the soil crushing rate map creation process by the soil crushing rate map creation device according to one embodiment of the present invention. Fig. 3 shows a flowchart explaining a method for calculating the soil crushing rate from an area, as an example.

[0036] 3, first, the data acquisition unit 12 acquires soil image data obtained by photographing the soil in the work area (step S11). Then, the image processing unit 13 processes the soil image data to make it suitable for image analysis to calculate the soil crushing rate (step S12).

[0037] Next, in step S13, the calculation unit 14 classifies the clods in the soil image data by size and calculates the area of ​​each clod. Then, the calculation unit 14 calculates the occupancy rate of the area obtained by subtracting the area of ​​clods of a predetermined size or larger from the total area of ​​the soil image in the soil image data (step S14).

[0038] In step S15, the map creation unit 15 maps the soil crushing rate on a map representing the work area at a position corresponding to the space where the soil image was captured. As mentioned above, the soil crushing rate is not necessarily calculated for all unit spaces. Then, it is determined whether data processing has been performed for all unit spaces on the map (step S16), and if data processing has been performed for all unit spaces (Yes), the soil crushing rate map is completed and the process ends. In step S16, if data processing has not been performed for all unit spaces on the map (No), the process returns to step S11 and the soil crushing rate mapping process is repeated.

[0039] According to the soil crushing rate map creation method and soil crushing rate map creation device 10 of one embodiment of the present invention, a soil crushing rate map of the entire field is created using photographed images of the soil, making it easy to create the soil crushing rate map. In addition, since the soil image data used to calculate the soil crushing rate is subjected to image processing before the soil crushing rate map is calculated, the soil crushing rate can be calculated with high accuracy.

[0040] [Software implementation example] The functions of the soil crushing rate map creation device 10 (hereinafter referred to as the "device") can be realized by a program that causes a computer to function as the device, and a program that causes a computer to function as each control block of the device (particularly each part included in the control unit 11).

[0041] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The control device and storage device execute the program, thereby realizing the functions described in each of the above embodiments.

[0042] The program is non-transitory and is stored in one or more computer-readable storage media. The program may be recorded on a recording medium. This recording medium may or may not be included in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0043] Furthermore, some or all of the functions of the control blocks can be realized by logic circuits. For example, an integrated circuit in which a logic circuit that functions as each of the control blocks is formed is also included in the scope of the present invention. In addition, the functions of the control blocks can also be realized by, for example, a quantum computer.

[0044] Furthermore, each process described in each of the above embodiments may be implemented using AI (Artificial Intelligence). In this case, the AI ​​may be executed by the control device, or may be executed by another device (for example, an edge computer or a cloud server).

[0045] (Additional notes) The present invention can also be expressed as follows.

[0046] The method for creating a soil crushing rate map according to aspect 1 of the present invention includes a soil crushing rate calculation step of calculating the soil crushing rate of the soil in a soil image by referring to predetermined characteristic values ​​of the soil mass in the soil image taken of the soil in the work area, and a map creation step of mapping the soil crushing rate on a map representing the work area to a position corresponding to the space in which the soil image was taken.

[0047] A method for creating a soil crushing rate map according to aspect 2 of the present invention may be the same as that of aspect 1, in which in the map creation process, the work area to be worked on is divided into a plurality of unit spaces, and for each unit space, the crushing rate calculated from a soil image taken of the space closest to its center point is mapped as the crushing rate of that unit space.

[0048] In the method for creating a soil crushing rate map according to aspect 3 of the present invention, in the above-mentioned aspect 1 or 2, in the crushing rate calculation step, the soil crushing rate may be calculated as the occupancy rate of the area obtained by subtracting the area of ​​soil masses exceeding a predetermined size from the area of ​​the soil in the soil image.

[0049] In the method for creating a soil crushing rate map according to aspect 4 of the present invention, in any of aspects 1 to 3 above, the crushing rate calculation step may involve calculating the soil crushing rate using a preprocessed soil image obtained by image processing the soil image, which includes an image of soil with at least a partial shadow overlapping it.

[0050] A method for creating a soil crushing rate map according to aspect 5 of the present invention is a method for creating a soil crushing rate map as described in claim 1 or 2, wherein in any of the above aspects 1 to 4, in the soil crushing rate calculation process, the soil image may be an image of the soil after work by a photographing device provided on a work machine working on the soil in the work area.

[0051] The soil crushing rate map creation device of aspect 6 of the present invention includes a soil crushing rate calculation unit that calculates the soil crushing rate of the soil in a soil image by referring to predetermined feature values ​​of the soil mass in the soil image taken of the soil in the work area, and a map creation unit that maps the soil crushing rate to a position on a map representing the work area corresponding to the space where the soil image was taken.

[0052] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Example]

[0053] The crushing ratio calculated by the soil crushing ratio map creation method according to one embodiment of the present invention was compared with the crushing ratio measured by the sieving method. The crushing ratio was measured by the conventional sieving method in the field where the soil crushing ratio map shown in Figure 2 was created. The crushing ratios at corresponding positions on the soil crushing ratio map shown in Figure 2 were extracted and compared. The results are shown in Figure 4. The dashed line in Figure 4 indicates an approximate straight line.

[0054] As shown in Figure 4, a significant correlation was obtained at the 5% level between the crushed soil ratio (estimated crushed soil ratio) calculated by the method for creating a soil crushed soil ratio map according to one embodiment of the present invention and the crushed soil ratio (measured crushed soil ratio) actually measured by the sieve method. This indicates that the calculation of the crushed soil ratio using the method for creating a soil crushed soil ratio map according to one embodiment of the present invention is useful. [Explanation of symbols]

[0055] 10. Soil fragmentation rate map creation device 14 Calculation section 15 Map Creation Department 100 Soil Crushing Rate Mapping System

Claims

1. a soil crushing rate calculation step of calculating the soil crushing rate of the soil in the soil image by referring to predetermined feature values ​​of the soil mass in the soil image obtained by photographing the soil in the work target area; a map creation process of mapping the soil crushing rate on a map representing the work area at a position corresponding to the space where the soil image was taken; A method for creating a soil crushing rate map, comprising:

2. 2. A method for creating a soil crushing rate map as described in claim 1, wherein in the map creation process, the work area is divided into a plurality of unit spaces, and for each unit space, the crushing rate calculated from a soil image taken of the space closest to its center point is mapped as the crushing rate of that unit space.

3. 3. A method for creating a soil crushing rate map as described in claim 1 or 2, wherein in the soil crushing rate calculation step, the area occupancy rate obtained by subtracting the area of ​​soil clods exceeding a predetermined size from the area of ​​soil in the soil image is calculated as the soil crushing rate.

4. 3. A method for creating a soil crushing rate map as described in claim 1 or 2, wherein in the soil crushing rate calculation step, the soil crushing rate is calculated using a preprocessed soil image obtained by image processing the soil image, which includes an image of soil with at least a portion of the soil being shaded.

5. A method for creating a soil crushing rate map as described in claim 1 or 2, wherein the soil image is an image of the soil after work by a work machine taken by a photographing device installed on a work machine working on the soil in the work area.

6. a soil crushing rate calculation unit that calculates the soil crushing rate of the soil in the soil image by referring to a predetermined feature value of the soil mass in the soil image obtained by photographing the soil in the work target area; a map creation unit that maps the soil crushing rate on a map representing the work area to a position corresponding to the space where the soil image was taken; A soil crushing rate map creation device equipped with the above.

Images