Plant removal device

Abstract

To improve efficiency of work for removing plants.SOLUTION: A plant removing device includes a detection unit, a determination unit, an irradiation unit, and a storage unit. The detection unit detects a non-object plant on the basis of image data and detects the position of the non-object plant. The determination unit determines whether or not the detected non-object plant is a beam irradiation object. The irradiation unit radiates beams onto the non-object plant as an irradiation object. The storage unit stores the position of the non-object plant to which beams are radiated as irradiation information. The determination unit determines whether or not the non-object plant detected by the detection unit is an irradiation object on the basis of the position of the non-object plant and the irradiation information.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a plant removal device.

Background Art

[0002] There is known a self-propelled system that travels on farmland, detects weeds based on an image generated by a three-dimensional imager, and irradiates the detected weeds with a beam to remove the weeds (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, it may take a certain period of time until the weeds irradiated with the beam wither. Therefore, when removing weeds using the system disclosed in Patent Document 1, there is a risk that the beam is irradiated again to the weeds that are expected to wither due to the beam already being irradiated, resulting in a decrease in work efficiency.

[0005] One aspect of the present disclosure aims to improve the efficiency of the work of removing plants.

Means for Solving the Problems

[0006] One aspect of the present disclosure is a plant removal device, which includes an image sensor, a detection unit, a determination unit, an irradiation unit, and a storage unit. The image sensor is configured to generate image data indicating an image of the ground. The detection unit designates a predetermined plant as a target plant, and plants that are not the target plant as non-target plants, and is configured to detect non-target plants based on the image data and detect the positions of the non-target plants. The determination unit is configured to determine whether the non-target plants detected by the detection unit are irradiation targets for irradiating beams. The irradiation unit is configured to irradiate the non-target plants determined to be irradiation targets with beams. The storage unit is configured to store the positions of the non-target plants irradiated with the beams as irradiation information. The determination unit is configured to determine whether the non-target plants detected by the detection unit are irradiation targets based on the positions of the non-target plants and the irradiation information.

[0007] According to the above configuration, it is possible to suppress the irradiation of beams to non-target plants that have already been irradiated with beams and may wither in the future. Therefore, it is possible to suppress the time and power required for plant removal, and improve the efficiency of the work of removing plants.

[0008] In one aspect of the present disclosure, the determination unit may be configured to determine that the non-target plants detected by the detection unit are irradiation targets when the positions of the non-target plants detected by the detection unit are not included in the irradiation information. According to the above configuration, when non-target plants that have not been irradiated with beams are detected, the non-target plants can be made irradiation targets for the beams.

[0009] In one aspect of the present disclosure, the storage unit may be configured to store, as irradiation information, not only the positions of the non-target plants irradiated with the beams but also the irradiation time, which is the time when the non-target plants are irradiated with the beams. The determination unit may be configured to determine whether the non-target plants detected by the detection unit are irradiation targets, taking into account the irradiation time.

[0010] According to the above configuration, it is possible to determine whether to irradiate the unintended plant with the beam again according to the elapsed time after the beam is irradiated to the unintended plant. Therefore, it is possible to appropriately select the unintended plant to be irradiated with the beam.

[0011] In one aspect of the present disclosure, when the position of the unintended plant detected by the detection unit is included in the irradiation information, the determination unit may be configured to determine the unintended plant as an irradiation target if a predetermined period has elapsed from the irradiation time of the unintended plant included in the irradiation information.

[0012] According to the above configuration, it is possible to irradiate the plant that does not wither even after a certain period has elapsed after the beam irradiation, with the beam again. In one aspect of the present disclosure, the image data may show an image of the ground where the target plant is located. The detection unit may be configured to detect the unintended plant based on the image data and detect the position of the unintended plant based on the position of the target plant in the image data.

[0013] According to the above configuration, the position of the unintended plant can be suitably detected.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0015] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. It should be noted that the embodiments of the present disclosure are not limited to the following embodiments at all, and various forms can be adopted as long as they belong to the technical scope of the present disclosure.

[0016] [1. Summary] The weed removal device 1 of this embodiment removes weeds (in other words, unwanted plants), which are plants other than crops (in other words, target plants), in the cultivated land where crops are cultivated (see Fig. 1). The weed removal device 1 (in other words, the plant removal device) is self-propelled, detects weeds while traveling on the cultivated land 2, and performs weed removal work by irradiating the detected weeds with a beam.

[0017] The weed removal device 1 includes a control unit 10, a power source 11, a laser oscillator 12, a laser head 13, an optical system 14, a camera 15 (in other words, an image sensor), a lighting 16, a traveling unit 17, a housing 18, and a cover 19. On the ground directly below the weed removal device 1 (in other words, the housing 18) in the cultivated land 2, a working area 1A with a predetermined shape (for example, a quadrilateral) is formed. Then, with the traveling stopped, the weed removal device 1 detects the weeds in the working area 1A and irradiates the weeds with a beam.

[0018] The control unit 10 is a part that comprehensively controls the weed removal device 1 and includes a CPU and a memory. The CPU executes the program stored in the memory, whereby various functions of the weed removal device 1 are realized. Note that the various functions realized by the control unit 10 are not limited to being realized by the execution of a program, and a part or all of them may be realized using one or more hardware.

[0019] In addition to this, the control unit 10 is configured to detect the position of the weed removal device 1 (hereinafter, the current location). Specifically, the control unit 10 may detect the current location by, for example, GPS, or may detect the speed and traveling direction of the weed removal device 1 by a sensor and detect the current location based on these detection results.

[0020] The power source 11 includes a rechargeable battery and supplies power to each part in the weed removal device 1. The laser oscillator 12, the laser head 13, and the optical system 14 output a beam for removing weeds. Specifically, a beam is generated by laser oscillation in the laser oscillator 12, and the optical path of the beam is adjusted by the laser head 13 and the optical system 14.

[0021] The housing 18 houses the control unit 10, the power supply 11, the laser oscillator 12, the laser head 13, and the optical system 14. The camera 15 is provided at the lower part of the housing 18 and photographs the working area 1A below the housing 18.

[0022] The illumination 16 is provided at the lower part of the housing 18 and illuminates the working area 1A. The cover 19 is provided so as to protrude downward from the lower surface of the housing 18 and has a wall portion that surrounds the working area 1A from the side. Thereby, the brightness of the working area 1A illuminated by the illumination 16 is maintained.

[0023] The traveling unit 17 is provided below the cover 19 and includes tires and a motor for traveling the weeding device 1. [2. Route Information] The weeding device 1 travels on the cultivated land according to the route information stored in the memory of the control unit 10 and performs weeding. An example of the route information shown in FIG. 2 shows the positions of the ridges 20 and the positions of the crops 21 in the cultivated land 2, the route 22 when the weeding device 1 travels on the cultivated land 2, and the positions on the route 22 where the weeding device 1 stops and performs the weeding operation.

[0024] As an example, the cultivated land 2 has four ridges 20, and in each ridge 20, six crops 21 are cultivated at positions set at regular intervals (for example, 60 cm). In addition, an integer X (1 to 4) is set as identification information for each ridge 20, and an integer Y (1 to 6) is set as identification information for each crop 21 in each ridge 20. Then, the positions of the respective crops in the cultivated land 2 are specified by the coordinates of X and Y.

[0025] In the path information of FIG. 2, as an example, a path 22 is set along each ridge 20, and the weeding device 1 travels along the path 22 with the ridge 20 positioned between the tires of the traveling unit 17. Also, in the path information, as an example, a starting point 22A is set adjacent to the crop 21 located at the coordinates (4, 1), and an end point 22B is set adjacent to the crop 21 located at the coordinates (1, 1). Then, the path 22 is set along each ridge 20 from the starting point 22A to the end point 22B.

[0026] Also, in the path information, the position of each crop 21 is set as a stop position. When the weeding device 1 stops at the stop position, the crop 21 at the stop position is located in the working area 1A of the weeding device 1 (see FIG. 1). The weeding device 1 travels along the path 22 and stops at each stop position to perform weeding work around the crop 21 at the stop position.

[0027] Note that the stop position of the weeding device 1 can be appropriately determined according to, for example, the size of the crop 21, the interval between adjacent crops 21, etc. Also, for example, stop positions can be set corresponding to a plurality of crops 21, and when the weeding device 1 stops at the stop position, a plurality of crops 21 may exist in the working area 1A.

[0028] Also, the positions of each ridge 20, each crop 21, the position of the path 22, and the stop position in the path information may be determined by, for example, the longitude and latitude detected by GPS. In addition to this, these positions may be determined as relative positions with respect to a reference point (for example, the position of the starting point 22A) defined on the cultivated land 2.

[0029] Also, the path information may be set by the user of the weeding device 1 or may be set by the vendor providing the weeding device 1. [Regarding weeding by the beam] As described above, the weeding device 1 stops at each stop position on the path 22, detects weeds, and performs a weeding operation by irradiating the detected weeds with a beam. The weeds irradiated with the beam do not wither immediately, but begin to wither after a certain period (for example, about 1 to 7 days).

[0030] On the other hand, it is assumed that the weeding operation of the same cultivated land is performed again by the weeding device 1 within several days after the weeding operation of the cultivated land by the weeding device 1. In such a case, there is a possibility that the weeds irradiated with the beam during the previous weeding operation have not withered, and there is a possibility that the beam is irradiated more than necessary to the weeds that have already been irradiated with the beam and are expected to wither in the future.

[0031] Therefore, the control unit 10 of the weeding device 1 registers the weeds irradiated with the beam in the irradiation information. The irradiation information is stored in the memory of the control unit 10 and includes information indicating the position of the registered weeds and the date and time (hereinafter referred to as the irradiation time) when the beam was irradiated to the weeds. Then, the control unit 10 determines whether or not the detected weeds have been irradiated with the beam based on the irradiation information, and excludes the weeds that have already been irradiated with the beam and are expected to wither in the future from the irradiation target of the beam.

[0032] [4. Weeding process] Next, the weeding process, which is the process when the weeding device 1 performs a weeding operation according to the path information, will be described using the flowchart of FIG. 3. When starting the weeding process, the weeding device 1 travels to the start point of the path, or the weeding device 1 is placed at the start point by the user or the like. Then, this process is started by the weeding device 1 located at the start point.

[0033] In S100, the control unit 10 of the weeding device 1 detects the current position of the weeding device 1 and specifies the closest stop position when moving along the path indicated in the path information. Then, the control unit 10 controls the traveling unit 17, moves to the specified stop position, and stops at the stop position, and then proceeds to S105.

[0034] Incidentally, when the weeding device 1 performs a weeding operation according to the path information in FIG. 2, when it reaches the stop position, one crop 21 is located directly below the weeding device 1, and the crop 21 and the area around the crop 21 are present in the above-described work area 1A (see FIG. 1). However, not limited to this, a plurality of crops may be present in the work area 1A, or no crops may be present.

[0035] In S105, the control unit 10 turns on the illumination 16 to illuminate the work area 1A, and at the same time, photographs the work area 1A with the camera 15 to generate image data. Then, the control unit 10 performs image recognition based on the image 3 (see FIG. 4) indicated by the image data, and detects the crop 32 and the weed 30 present in the work area 1A.

[0036] In S110, the control unit 10 detects the position of each detected weed 30 based on the position of the crop 32 present in the current work area 1A. Specifically, first, the control unit 10 specifies the coordinates (X, Y) of the position of the crop 32 cultivated at the current stop position as the approximate position. Next, the control unit 10 detects the detailed position of each weed 30 based on the position of the crop 32 in the image 3. That is, the control unit 10 sets rectangular frames 31, 33 surrounding the recognized weeds 30 and crops 32 in the image 3, and sets an xy coordinate system with the center of the frame 33 surrounding the crop 32 as the origin. Further, the control unit 10 detects the coordinates (x, y) of the center of the frame 31 surrounding the weed 30 in the xy coordinate system as the detailed position of the weed 30. Then, the control unit 10 sets the approximate position (X, Y) of the crop 32 at the stop position and the detailed position (x, y) of the weed 30 detected at the stop position as the position of the weed 30.

[0037] In S115, the control unit 10 determines whether each detected weed 30 is a target for beam irradiation based on the position of each detected weed 30 and the irradiation information stored in the memory. Specifically, when the position of the detected weed 30 is not included in the irradiation information and the weed 30 is not registered in the irradiation information, the control unit 10 regards that the beam is not irradiated to the weed 30, and determines that the weed 30 is a target for beam irradiation.

[0038] In addition, the position of the detected weed 30 is included in the irradiation information. When the weed 30 is already registered in the irradiation information, the control unit 10 grasps the irradiation time of the previous beam to the weed 30 from the irradiation information and specifies the current date, year, month, and time. Then, when the elapsed time from the irradiation time of the previous beam to the weed 30 exceeds a predetermined threshold value (for example, 7 days), the control unit 10 determines that the weed 30 is an object to be irradiated with the beam. On the other hand, if not, the control unit 10 excludes the weed 30 from the objects to be irradiated with the beam.

[0039] Note that when the detected weed 30 is already registered in the irradiation information, the control unit 10 may exclude the weed 30 from the objects to be irradiated with the beam regardless of the elapsed time. In S120, when there is a weed determined to be an irradiation target, the control unit 10 irradiates all the weeds that have become irradiation targets with the beam.

[0040] In S125, when the control unit 10 irradiates the weed with the beam, it updates the irradiation information. Specifically, when irradiating an unregistered weed 30 with the beam, the control unit 10 registers the weed 30 in the irradiation information by saving the position of the weed 30 and the current date, year, month, and time (in other words, the irradiation time of the beam to the weed 30) as part of the irradiation information. When irradiating a registered weed 30 with the beam, the control unit 10 saves the current date, year, month, and time (in other words, the irradiation time of the beam to the weed 30) as part of the irradiation information of the weed 30.

[0041] In S130, the control unit 10 determines whether or not the weeding device 1 has stopped at all the stop positions set in the path information. Then, when an affirmative determination is obtained (S130: Yes), the control unit 10 moves to the end point of the path. On the other hand, when a negative determination is obtained (S130: No), the control unit 10 shifts to S100.

[0042] [5. Effects] (1) According to the above embodiment, based on the detected position of the weed and the irradiation information, it is determined whether the weed is to be used as the irradiation target of the beam. Therefore, it is possible to suppress the beam from being irradiated to weeds that have already been irradiated with the beam and may wither in the future. Accordingly, the time and power required for weed removal can be suppressed, and the efficiency of the work of removing weeds can be improved.

[0043] (2) Further, when a weed that is not registered in the irradiation information is detected, the weed becomes the radiation target of the beam. Therefore, it is possible to use, as the irradiation target of the beam, weeds that have not been irradiated with the beam.

[0044] (3) Further, when a weed is detected, based on the current date, time, and the previous beam irradiation time to the weed indicated by the irradiation information, it is determined whether the weed is to be used as the irradiation target of the beam. Therefore, it is possible to determine whether to irradiate the weed with the beam again according to the elapsed time after the beam is irradiated to the weed. Therefore, it is possible to appropriately select the weeds to be irradiated with the beam.

[0045] (4) Further, when a weed registered in the irradiation information is detected, if the elapsed time from the beam irradiation time to the weed has reached a predetermined threshold value, the weed becomes the irradiation target of the beam. Therefore, it is possible to irradiate again with the beam weeds that do not wither even after a certain period has elapsed after the beam irradiation.

[0046] (5) On the other hand, if the elapsed time has not reached the threshold value, the weed is excluded from the irradiation target of the beam. Therefore, it is possible to suppress the beam from being irradiated to plants that have already been irradiated with the beam and may wither in the future. Accordingly, the time and power required for plant removal can be suppressed, and the efficiency of the work of removing plants can be improved.

[0047] (6) Further, the position of the weed is detected based on the position of the crop. Therefore, the position of the weed can be accurately detected. [6. Other Embodiments] (1) In the above embodiment, the position of the detected weed is determined by the approximate position (X, Y) of the crop at the stop position of the weeding device 1 and the detailed position (x, y) of the weed based on the position of the crop. However, the position of the weed is not limited to this and can be detected by various methods. Specifically, for example, the control unit 10 of the weeding device 1 may detect the position of the image captured by the camera 15 based on the current location detected by GPS, and also detect the relative position of the weed in the image. Then, the control unit 10 may use the detection results of these positions as the position of the weed.

[0048] (2) In the weeding process of the above embodiment, after the beam is irradiated to the detected weed, the irradiation information is updated, and unregistered weeds are newly registered in the irradiation information, or the irradiation time of the registered weeds is stored as the irradiation information. However, the update timing of the irradiation information is determined as appropriate. Specifically, for example, after the control unit 10 determines that the detected weed is the irradiation target of the beam, it may update the irradiation information corresponding to the weed in the same manner before irradiating the weed with the beam.

[0049] (3) In the above embodiment, the weeding device 1 performs weeding work in the cultivated land 2. However, the weeding device 1 may be used to remove unwanted plants in places other than the cultivated land 2 where the target plant is cultivated or grows naturally (for example, parks, gardens, etc.). In addition to this, the weeding device 1 may be used to remove plants in places where the target plant does not exist. That is, all plants existing in a specific place are regarded as unwanted plants, and the weeding device 1 may be used to remove such unwanted plants.

[0050] (4) The weeding device 1 of the above embodiment is self-propelled and is configured to automatically travel according to the route information. However, the weeding device 1 may move along the route according to the operation from the user, or may be moved by another device or manually, and perform the weeding work in the same manner.

[0051] (5) The multiple functions of one component in the above embodiment may be realized by multiple components, or one function of one component may be realized by multiple components. Also, the multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Further, a part of the configuration of the above embodiment may be omitted. Also, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of other above embodiments.

[0052] [7. Corresponding relationships of language] S105 and S110 of the weeding process correspond to examples of a detection unit, S115 corresponds to an example of a determination unit, S120 corresponds to an example of an irradiation unit, and S125 corresponds to an example of a storage unit, respectively.

Explanation of reference signs

[0053] 1... Weeding device, 1A... Working area, 10... Control unit, 11... Power supply, 12... Laser oscillator, 13... Laser head, 14... Optical system, 15... Camera, 2... Cultivated land, 21... Crop, 22... Route, 3... Image, 30... Weed, 32... Crop.

Claims

1. A plant removal device, an image sensor configured to generate image data showing an image of the ground, a detection unit configured to set a predetermined plant as a target plant, set plants other than the target plant as non-target plants, detect the non-target plants based on the image data, and detect the positions of the non-target plants, a determination unit configured to determine whether a non-target plant detected by the detection unit is an irradiation target for irradiating a beam, an irradiation unit configured to irradiate the non-target plant determined to be the irradiation target with the beam, and a storage unit configured to store the position of the non-target plant irradiated with the beam as irradiation information, wherein the determination unit is configured to determine whether the non-target plant detected by the detection unit is the irradiation target based on the position of the non-target plant and the irradiation information. Plant removal device.

2. The plant removal device according to claim 1, wherein the determination unit is configured to determine the non-target plant as the irradiation target when the position of the non-target plant detected by the detection unit is not included in the irradiation information. Plant removal device.

3. The plant removal device according to claim 1 or claim 2, wherein the storage unit is configured to store, as the irradiation information, in addition to the position of the non-target plant irradiated with the beam, an irradiation time which is the time when the non-target plant is irradiated with the beam, and the determination unit is configured to determine whether the non-target plant detected by the detection unit is the irradiation target, taking the irradiation time into further consideration. Plant removal device.

4. The plant removal device according to claim 3, wherein the determination unit is configured to determine the non-target plant as the irradiation target if a predetermined period has elapsed from the irradiation time of the non-target plant included in the irradiation information when the position of the non-target plant detected by the detection unit is included in the irradiation information. Plant removal device.

5. The plant removal device according to any one of claims 1 to 4, wherein the image data shows an image of the ground where the target plant is located, and the detection unit is configured to detect the non-target plants based on the image data and detect the positions of the non-target plants based on the position of the target plant in the image data. Plant removal device.

Images