Laser weeding machine and laser weeding method and device

Abstract

The invention discloses a laser weeding machine and a laser weeding method and device, relates to the technical field of weeding, and aims at solving the problems that an existing weeding mode pollutes the environment, weeding is not thorough, and weeding is carried out mistakenly. The laser weeding machine comprises a tractor and a laser weeding system carried on the tractor. In the laser weeding system, a high-definition camera collects a ground image; the image recognition system processes the collected ground image; the laser adjusts the working state according to the output of the image recognition system; the control module controls the galvanometer system to work according to the output of the image recognition system; the galvanometer system adopts laser output by the laser for scanning; the power module provides working power for the control module. The laser weeding method comprises the following steps: processing a collected ground image so as to identify a weed target from the ground image; if a weed target is recognized, a control signal is sent to the galvanometer system, so that laser emitted by the laser is reflected by the galvanometer system and then irradiates on weeds, and weeding is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of weeding, and in particular to a laser weeding machine, a laser weeding method and a laser weeding device. Background Art

[0002] Crop cultivation is inevitably affected by weeds. Currently, two common methods of weed control are chemical and mechanical. Chemical weed control involves spraying herbicides on plants or in the soil, which can easily cause soil and air pollution. Mechanical weed control relies on manual identification of weeds. Even if accurate identification is achieved, it can be difficult to completely remove weeds growing among other plants, or even lead to the accidental removal of other plants.

[0003] In summary, existing weed control methods have the problems of environmental pollution, incomplete weed control, and mistaken weed control. Summary of the Invention

[0004] The purpose of this application is to solve or alleviate the above problems and to provide a laser weeding machine, a laser weeding method and a device.

[0005] The laser weeder of the present application includes: a tractor and a laser weeding system mounted on the tractor; the laser weeding system includes: a power module, a control module, an image recognition system, a laser, a high-definition camera and a galvanometer system; the high-definition camera is used to collect ground images; the image recognition system is connected to the high-definition camera and is used to process the images collected by the high-definition camera; the laser is connected to the image recognition system and is used to adjust the working state according to the output of the image recognition system; the control module is respectively connected to the high-definition camera, the image recognition system and the galvanometer system, and is used to control the operation of the galvanometer system according to the output of the image recognition system; the galvanometer system is used to scan using the laser output by the laser; the power module is connected to the control module and is used to provide working power to the control module.

[0006] Optionally, the tractor is equipped with a central control system and at least six wheels, each wheel is equipped with an automatic recognition system; the automatic recognition system is used to identify the flatness of the road surface; the central control system is connected to the automatic recognition system and can control the height of the wheel according to the recognition result of the automatic recognition system.

[0007] Optionally, the laser weeding system is mounted on the chassis of the tractor.

[0008] Optionally, the laser weeding system is mounted on the chassis of the tractor via a liftable bracket.

[0009] Optionally, the output wavelength of the laser is 941 nm or 915 nm, and the maximum output power is 2000 W.

[0010] Optionally, the laser includes a laser body and a beam splitting system, and the beam splitting system can split the laser output by the laser body into several beams.

[0011] Optionally, the beam splitting system includes a fiber optic beam splitter, several absorption boxes and several servos, the fiber optic beam splitter splits the laser output by the laser body into several laser beams, the several absorption boxes correspond one-to-one to the several laser beams, and the several servos are used to control the several absorption boxes respectively.

[0012] Optionally, the laser weeding system further includes a reflector, and the laser emitted by the galvanometer system is incident on the reflector and reflected to the ground by the reflector.

[0013] The laser weeding method of the present application includes: processing the collected ground image to identify the weed target therefrom; if the weed target is identified, sending a control signal to the galvanometer system so that the laser emitted by the laser is reflected by the galvanometer system and irradiated on the weed to achieve weeding.

[0014] The laser weeding device of the present application includes: a target recognition unit, which is suitable for processing the collected ground image to identify the weed target therefrom; and a weeding unit, which is suitable for sending a control signal to the galvanometer system when the weed target is identified, so that the laser light emitted by the laser is reflected by the galvanometer system and irradiated on the weeds to achieve weeding.

[0015] The laser weeder, laser weeding method and device of the present invention use image recognition technology as a target recognition means, which can improve the accuracy of weed recognition and avoid mistaken weeding and missed weeding. The galvanometer system is used as a laser target to burn weeds, which can ensure the accuracy of weeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the principle of a laser weeding system according to an embodiment of the present application;

[0017] Figure 2 is a structural schematic diagram of a beam splitting system according to an embodiment of the present application;

[0018] Figure 3 is a structural diagram of a module according to an embodiment of the present application;

[0019] Figure 4 is a flow chart of a laser weeding method according to an embodiment of the present application;

[0020] Figure 5Schematic diagram of the structure of a laser weeding device according to an embodiment of the present application. DETAILED DESCRIPTION

[0021] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0022] As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms "comprise", "include" indicate the presence of the described features, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, operations, elements, components, items, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Thus, "A, B, or C" or "A, B, and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B, and C". Exceptions to this definition occur only when the combination of elements, functions, or operations is inherently mutually exclusive in some way.

[0023] In response to the problems of existing weeding methods such as environmental pollution, incomplete weeding and mistaken weeding, the present invention provides a laser weeding machine, a laser weeding method and a device that can automatically and accurately identify and remove weeds.

[0024] The laser weeding machine of the embodiment of the present application mainly includes a tractor and a laser weeding system. The laser weeding system is installed on the tractor, for example, on the chassis of the tractor.

[0025] As a preferred embodiment of the present application, the laser weeding system is installed on the tractor chassis through a liftable bracket, which facilitates the adjustment of the height of the laser weeding system and enables weeding in various environments.

[0026] In the embodiment of the present application, the laser weeding system can collect ground images, extract weed targets from the images, and then use lasers to burn the weeds to achieve weeding.

[0027] As a preferred embodiment of the present application, the tractor has at least six wheels. To ensure the accuracy of the laser weeding system during driving, each wheel is equipped with an automatic recognition system. The automatic recognition system includes a height detection device and a lifting system. The height detection device is used to sense the height of the wheel to which it belongs. If the position of a wheel is significantly higher than the other wheels, it indicates that the position of the wheel is raised. At this time, the tractor should be in a tilted state, causing the angle of the laser weeding system to change. To restore the tractor to its initial state (the initial state is defined as the state when the tractor is on flat ground) to ensure the accuracy of weeding, the lifting system of the wheel drives the wheel to rise until the wheel is off the ground. The tractor relies on the remaining five wheels to move forward and maintain balance. Before weeding, the tractor is driven to a flat road section and the height detection devices of each automatic recognition system are calibrated. The state of the tractor at this time is regarded as the initial state.

[0028] Figure 1 FIG. 1 is a schematic diagram of the principle of a laser weeding system according to an embodiment of the present application. Figure 1 As shown, the laser weeding system includes a power module 1, a control module 2, an image recognition system 3, a laser 4, a high-definition camera 5, and a galvanometer system 6. The power module 1 is connected to the control module 2, which is connected to the image recognition system 3, the high-definition camera 5, and the galvanometer system 6 respectively. The high-definition camera 5 is connected to the image recognition system 3. The image recognition system 3 is connected to the laser 4.

[0029] The high-definition camera 5 can be a 1080P camera, providing high-definition images to the image recognition system 3, ultimately completing the target information collection. The laser 4 can be a continuous-wave laser with an output wavelength of 941nm and a maximum output power of 2000W, providing sufficient energy for high-temperature weed burning. The galvanometer system 6 can rapidly scan based on the information fed back to the control module 2 and laser 4 by the image recognition system 3, capturing target information and reflecting the laser light output by the laser 4 onto the target weeds to burn them.

[0030] The power module 1 provides working power to the control module 2. The control module 2 sends instructions to the high-definition camera 5 and the image recognition system 3. After receiving the instructions, the high-definition camera 5 starts to collect ground images and sends the collected images to the image recognition system 3. The image recognition system 3 processes the images sent by the high-definition camera 5 to identify weed targets. When a weed target is identified, the image recognition system 3 sends a signal to the control module 2 and the laser 4. The signal sent by the image recognition system 3 to the control module 2 contains at least the location information of the weed target. The signal sent by the image recognition system 3 to the laser 4 serves as the start signal of the laser 4. After receiving the start signal, the laser 4 starts to generate laser light. After receiving the signal from the image recognition system 3, the control module 2 controls the galvanometer system 6 to reflect the laser light at a specific angle so that the reflected laser light is irradiated on the weeds, burning the weeds at high temperature and completely removing the weeds.

[0031] In one implementation, the laser 4 includes a laser body and a beam splitting system, which can split the laser output from the laser body into several beams. Figure 2 As shown, the beam splitting system mainly includes a fiber optic beam splitter 41, several absorption boxes 43 and several servos. The laser generated by the laser body is coupled into the fiber optic beam splitter 41, and the laser is divided into several beams. Each laser beam passes through a collimating lens 42 to compress the divergence angle. An absorption box 43 is set near the propagation path of each laser beam. The absorption box 43 can rotate under the control of the servo. When a certain laser beam is needed for weeding, the absorption box 43 corresponding to the laser beam rotates under the control of the servo to allow the laser to be emitted smoothly. When a certain laser beam is not needed for weeding, the absorption box 43 corresponding to the laser beam rotates to the laser propagation path under the control of the servo to block and absorb the laser. Correspondingly, the galvanometer system 6 includes several galvanometers 61, one galvanometer 61 is arranged on the propagation path of each laser beam, and each galvanometer 61 is independently controlled to achieve independent scanning of several laser beams.

[0032] In one implementation, the laser 4 is a semiconductor laser with an output wavelength of 915 nm. The optical fiber beam splitter 41 uses quartz optical fiber, and the core diameter / cladding of each output optical fiber is 200 / 220 μm, Na is 0.22, and the quartz refractive index n is about 1.45. In order to achieve efficient weeding, the laser spot irradiated on the weeds needs to meet certain power density and spot diameter. The higher the power density, the faster the weed damage rate. However, high power density requires compressing the spot diameter, and the reduction in spot diameter will reduce the weeding rate. Assuming that the reasonable spot diameter is 3-8 mm, the power density is 4 W / mm. 2 Up to 28W / mm 2 In order to meet the above requirements, a collimating lens 42 is used to transform the light beam. Taking the spot diameter D as 5 mm as an example, the focal length f value of the collimating lens 42 is as follows:

[0033]

[0034] Where θ is the beam divergence angle.

[0035] by Figure 2 Taking the illustrated structure as an example, the laser output power of laser 4 is 2000W, which is split into eight beams by the beam splitting system. Each beam has a power of 250W, and all eight beams can be controlled individually for weed control. The scanning range of the galvanometer system 6 is 28°, and the scanning amplitude is 500mm. That is, the coverage area d of each beam is 500mm, and the overlap d0 of adjacent beams is 5mm. The total coverage area D of the eight beams is 3965mm, meaning the operating amplitude of the laser weed control system is approximately 4m.

[0036] The xy-axis scanning range of the galvanometer 61 is ±14°. After the laser enters the galvanometer 61, the laser scans a square pyramidal area. To ensure that the scanning area of ​​a single galvanometer on the ground is S = d × d ≥ 500 mm × 500 mm, the distance h between the galvanometer 61 and the projection point (the weeds illuminated by the laser) is:

[0037]

[0038] The laser scanning square cone cannot be blocked by other equipment, otherwise it will cause damage to the equipment. The galvanometer 61 should be located at a height of more than 100 cm above the ground. This will cause a large amount of vacancy inside the laser weeding system and also easily cause uneven distribution of the center of gravity of the equipment. In order to compress the vacant space between the galvanometer and the ground, a reflector 7 is installed between the galvanometer and the ground to compress the vacant space. The arrangement is as follows: Figure 3 As shown, after calculation, the size of the reflector 7 is shown in Table 1.

[0039] Table 1 Mirror dimensions

[0040] Distance between reflector and ground The distance between the reflector and the galvanometer Mirror size 50cm 50cm 25cm×25cm 60cm 40cm 20cm×20cm 70cm 30cm 15cm×15cm 80cm 20cm 10cm×10cm

[0041] Therefore, taking the galvanometer system 6 with a scanning amplitude of 500 mm as an example, the distance between the galvanometer system 6 and the ground is at least 1000 mm.

[0042] Collimating lens 42, absorption box 43, galvanometer system 6, and reflector 7 can be packaged into module 8. Collimating lens 42 is mounted on a sleeve, which is fixed to the interface of module 8. In the embodiment of the present application, the numerical aperture of each optical fiber of fiber optic beam splitter 41 is 0.22, and collimating lens 42 is a plano-convex lens with a focal length of 22.2 mm. The diameter of the light spot projected on the weeds is 5 mm.

[0043] During the operation of the above-mentioned laser weeding system, the high-definition camera 5 will collect the ground image and send it to the image recognition system 3. The image recognition system 3 will identify the weed targets from the ground image and mark the identified weed targets. Various methods can be used to control the galvanometer system 6 and the absorption box 43 to reflect / block the laser so as to reflect the laser onto the weeds. The embodiment of the present application does not specifically limit the control method of the galvanometer system 6 and the absorption box 43.

[0044] In one implementation, the image recognition system 3 divides the ground image into blocks to determine the coordinate parameters of the weed targets, establishes a target list based on the coordinate parameters of the weed targets, and plans the scanning path of the galvanometer system 6 based on the target list. The galvanometer system 6 marks according to the planned path. The targets in the target list are blocks in the ground image. If a block in the divided ground image contains weeds, the block is filled in the target list as a target. The planned path should cover all targets in the current ground image.

[0045] When dividing the ground image into blocks, it can be divided into blocks in a matrix form. For example, the ground image can be divided into M×N blocks. The number of blocks can be determined according to the spot size of each laser beam. Preferably, the area covered by each block is equal to the spot size of each laser beam.

[0046] It should be noted that when weed targets are detected in the ground image, the tractor should stop moving forward / backward and wait until all weeds in the current ground image are completely burned before continuing forward / backward. The high-definition camera 5 continuously captures ground images and sends them to the image recognition system 3 in real time. The image recognition system 3 identifies weed targets from the ground image and marks them. Next, the image recognition system 3 segments the ground image to determine the coordinate parameters of the weed targets. While the tractor remains stationary, the target list can be updated based on the coordinate parameters of the weed targets in the previous and next ground images, and a correction table can be established for the marking position of the galvanometer system 6. For example, if the block in row i, column j in the previous image is a weed, while the block in row i, column j in the current image is a non-weed, this indicates that the target weed in row i, column j has been eliminated. The target in row i, column j is deleted from the target list, completing the update of the target list at the current moment. During subsequent weeding operations, the marking position of the galvanometer system 6 can be corrected based on the correction table.

[0047] In a preferred embodiment, when dividing the ground image into blocks, the number of N is equal to the number of laser beams. Figure 2For example, if the beam splitting system splits the laser into eight beams, N is set to 8. During marking, the galvanometer system 6 is controlled to move the laser beam only in the longitudinal direction. When the light spot moves to a row in the ground image, if all eight blocks in that row are targets, all laser beams are activated for marking. If only a portion of the blocks in that row are targets, only the beams corresponding to the target positions are activated for marking. This embodiment, by properly setting the value of N, simplifies the control of the galvanometer system 6 and the servo.

[0048] The laser weeder of the embodiment of the present application has a weeding coverage width of 4±0.2m, a weeding speed of more than 8000mm / s, and a total laser weeding power of 2000W, with fast weeding speed and high efficiency; it uses image recognition technology as a target recognition means, with a 1080P image recognition speed of more than 10 frames per second, and can accurately provide target coordinates and scanning paths, which can improve the accuracy of weed recognition and avoid mis-weeding and missed weeding; it uses a galvanometer system 6 as a laser target to burn weeds, which can ensure the accuracy of weeding.

[0049] The present application also provides a laser weeding method. Figure 4 As shown, the laser weeding method 400 begins at step S410 .

[0050] In step S410, the collected ground image is processed to identify weed targets. If weed targets are identified, the process proceeds to step S420.

[0051] In step S420, a control signal is sent to the galvanometer system so that the laser light emitted by the laser is reflected by the galvanometer system and then irradiated on the weeds, thereby achieving weeding.

[0052] The laser weeding method 400 can be implemented by relying on the above-mentioned laser weeding machine, and its principles and effects are not described in detail.

[0053] The present application also provides a laser weeding device. Figure 5 As shown, the laser weeding device 500 includes a target recognition unit 510 and a weeding unit 520 .

[0054] The target recognition unit 510 is adapted to process the collected ground image to identify weed targets therefrom, and activate the weed removal unit 520 when the weed targets are identified.

[0055] The weeding unit 520 is adapted to send a control signal to the galvanometer system so that the laser light emitted by the laser is reflected by the galvanometer system and then irradiated on the weeds, thereby achieving weeding.

[0056] The laser weeding device 500 of the embodiment of the present application can perform the processing of each step of the laser weeding method 400. Its principles and effects are the same as those of the laser weeding method 400, and will not be repeated here.

[0057] The various techniques described herein may be implemented in conjunction with hardware or software, or a combination thereof. Thus, the methods and apparatus of the present invention, or certain aspects or portions of the methods and apparatus of the present invention, may be implemented in the form of program codes (i.e., instructions) embedded in a tangible medium, such as a removable hard disk, a USB flash drive, a floppy disk, a CD-ROM, or any other machine-readable storage medium, wherein when the program is loaded into a machine such as a computer and executed by the machine, the machine becomes an apparatus for practicing the present invention.

Claims

1. A laser weed remover, characterized in that: include: A tractor and a laser weeding system mounted on the tractor; The laser weeding system includes: a power module, a control module, an image recognition system, a laser, a high-definition camera and a galvanometer system; The high-definition camera is used to collect ground images; The image recognition system is connected to the high-definition camera and is used to process the images collected by the high-definition camera; The laser is connected to the image recognition system and is used to adjust the working state according to the output of the image recognition system; The control module is connected to the high-definition camera, the image recognition system and the galvanometer system respectively, and is used to control the operation of the galvanometer system according to the output of the image recognition system; The galvanometer system is used to scan using the laser output by the laser; The power supply module is connected to the control module and is used to provide working power to the control module.

2. The laser weed remover according to claim 1, wherein: The tractor is equipped with a central control system and at least six wheels, each of which is equipped with an automatic identification system; The automatic recognition system is used to identify the smoothness of the road surface; The central control system is connected to the automatic recognition system and can control the height of the wheel according to the recognition result of the automatic recognition system.

3. The laser weed remover according to claim 1, wherein: The laser weeding system is mounted on the chassis of the tractor.

4. The laser weed remover according to claim 3, wherein: The laser weeding system is installed on the chassis of the tractor through a liftable bracket.

5. The laser weed remover according to claim 1, wherein: The output wavelength of the laser is 941nm or 915nm, and the maximum output power is 2000W.

6. The laser weed remover according to claim 1, wherein: The laser comprises a laser body and a beam splitting system, and the beam splitting system can split the laser light outputted by the laser body into several beams.

7. The laser weed remover according to claim 6, wherein: The beam splitting system includes a fiber optic beam splitter, a plurality of absorption boxes and a plurality of servos. The fiber optic beam splitter divides the laser output by the laser body into a plurality of laser beams. The plurality of absorption boxes correspond one-to-one to the plurality of laser beams. The plurality of servos are used to control the plurality of absorption boxes respectively.

8. The laser weed remover according to claim 1, wherein: The laser weeding system further includes a reflector. The laser emitted by the galvanometer system is incident on the reflector and is reflected to the ground by the reflector.

9. A laser weeding method, characterized in that: include: Processing the collected ground images to identify weed targets; If the weed target is identified, a control signal is sent to the galvanometer system so that the laser light emitted by the laser is reflected by the galvanometer system and then irradiated on the weed to achieve weeding.

10. A laser weeding device, characterized in that: include: a target recognition unit, adapted to process the collected ground image to recognize weed targets therefrom; The weeding unit is adapted to send a control signal to the galvanometer system if the weed target is identified, so that the laser light emitted by the laser is reflected by the galvanometer system and then irradiated on the weeds to achieve weeding.

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