Near infrared spectrum vertical gradient soil layer detection equipment and detection method thereof

Abstract

The invention relates to a soil vertical soil layer detection technology, and provides a system comprising a soil near infrared spectrum detection base station and a spectrograph transportation device. The detection base station is composed of a double-cylinder-wall soil isolation rotating device, an automatic lifting platform, a near-infrared spectrometer auxiliary guiding platform, a vision auxiliary guiding landing platform and various soil sensors. The spectrograph transportation device comprises a spectrograph, a transportation unmanned aerial vehicle and a near infrared spectrum throwing assembly. When the system works, the unmanned aerial vehicle carrying the spectrograph flies to the position above a preset position and safely lands to a detection base station through vision assistance, and then the spectrograph is lowered into soil for scanning. And an internal mechanism of the detection base station enables the spectrometer to carry out accurate scanning at different depths, and the spectrometer is recovered and moved to the next detection point after the scanning is completed. According to the system, accurate detection and analysis of the soil hierarchical structure are realized, and the efficiency and accuracy of soil detection are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of soil spectrum detection, in particular to a near-infrared spectrum vertical gradient soil layer detection device and a detection method thereof. Background Art

[0002] Analyzing soil near-infrared spectra to determine soil properties is a non-invasive method for determining soil composition. This method works by emitting near-infrared light into the soil and measuring its absorption and reflection to determine the soil's organic matter and moisture content.

[0003] In the field of soil testing, examining vertical soil layers has always been a tedious and complex task. This often requires using a soil sampler to collect soil blocks 0 to 60 cm from the surface, dividing them into several soil samples at a certain gradient depth for separate testing. Furthermore, methods are used to establish a continuous relationship between the changes in soil layer composition. Monitoring the changes in soil composition over a region requires multiple soil sample collection and testing over different time periods, which consumes considerable time, manpower, and financial resources.

[0004] In response to these problems that need to be improved, the present invention proposes a vertical soil layer detection base station-UAV-near-infrared spectroscopy detection method, which can effectively reduce the cost of environmental vertical soil layer monitoring and realize large-scale, sustainable, and high-precision soil vertical layer near-infrared spectroscopy detection. Summary of the Invention

[0005] The present invention provides a near-infrared spectroscopy technology solution for scanning soil at different depths in a vertical soil layer, which is used to reduce the cost of collecting vertical soil layer spectral data. The solution specifically includes a spectrometer transportation device and a soil near-infrared spectroscopy detection base station.

[0006] The present invention provides a spectrometer transport device, comprising: The open-source F450 drone, responsible for transportation, is equipped with a Pixhawk flight controller, a Raspberry Pi processor, an M8N GPS module, and a gimbal camera. The M8NGPS module installed on the drone can provide longitude and latitude geographic location information; The gimbal camera is used to collect guidance image information of the landing platform for the UAV to land accurately; The near-infrared spectrometer casting assembly is installed in front of the UAV frame. The assembly mainly includes a casting servo and an automatic reel. The elastic line is led out from the automatic reel, passes through the card hole of the casting servo, and is fixed on the near-infrared spectrometer. The automatic take-up reel can draw out a certain length of elastic line from the reel under load conditions, and automatically rewind the elastic line into the reel under no-load conditions. The casting servo can push the elastic line into the round hole to lock the elastic line. After locking, the length of the elastic line outside the reel will not be stretched.

[0007] At the same time, the present invention provides a soil near-infrared spectrum detection base station. The lower half of the base station is buried in the soil layer, and the upper half provides a landing platform for drones and storage of devices. It mainly includes: The visual technology-assisted guidance platform has a circular surface consisting of a green inner circle and a blue outer circle. The drone lands within the green inner circle using the onboard gimbal camera and landing control program. A bracket is provided at the bottom of the visual technology-assisted guidance platform to provide support; On the other side, there is a device storage box with the bottom slightly higher than the soil surface. The box contains the battery power supply for maintaining the system, conventional environmental sensors, single-chip controller, etc. Conventional soil sensor detection parameters mainly include temperature, humidity, light, organic matter, pH, nitrogen, phosphorus and potassium; The main body of the base station is a double-walled soil isolation rotating device. This device consists of an outer cylinder and an inner cylinder. The outer cylinder is a cylindrical body with an inverted conical shell at the bottom. The outer cylinder and the inner cylinder are separated by a certain gap. The main function is to separate the inner cylinder from the underground soil layer. The inner cylinder is a cylindrical shape with an open top and a rotating gear installed at the bottom; The driving motor drives the transmission gear and the rotating gear to rotate, thereby driving the entire inner cylinder to rotate along the central axis; A supporting shaft is provided at the bottom of the inner cylinder, and a supporting plate is installed at the lower end of the shaft, and the supporting plate contacts the inner wall of the cone of the outer cylinder; A detection auxiliary platform is installed in the inner tube, which mainly includes a near-infrared spectrometer auxiliary guidance platform and an automatic lifting platform under the soil; The auxiliary guidance platform of the near-infrared spectrometer is a one-dimensional forward and backward moving platform. It relies on the rotation of the drive motor under the platform to drive the gear. The gear engages with the tooth pitch installed on the chassis. The rotation of the gear drives the platform to move forward or backward. The underground automatic lifting platform is a one-dimensional up and down moving platform. The fixed plate is placed perpendicular to the cylindrical chassis. A threaded rod and two fixed rods are installed on the fixed plate. A driving motor is installed at the bottom of the cylinder, which is connected to a threaded rod through an adapter. The rotation of the motor can drive the threaded rod. Two fixed rods play a stabilizing role; Screw holes are installed on the auxiliary guide platform of the near-infrared spectrometer. The threaded rod passes through the screw holes. The rotation of the threaded rod can drive the platform to move upward or downward.

[0008] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a schematic diagram of the soil near-infrared spectrum detection base station structure of the present invention; Figure 2 This is a diagram showing the components inside the device storage box of the present invention; Figure 3 This is a perspective view of the soil near-infrared spectrum detection base station structure of the present invention; Figure 4 Demonstration of the visual technology of the present invention assisting in guiding the landing of a transport drone; Figure 5 This is a schematic diagram of the double-wall soil isolation rotating device of the present invention; Figure 6 This is a schematic diagram of the near-infrared spectrum casting assembly of the present invention; Figure 7 A physical diagram of a transport drone equipped with a throwing servo according to the present invention; Figure 8 This is a schematic diagram of the automatic lifting and near-infrared spectrometer auxiliary guidance platform under the soil of the present invention; Figure 9 This is a physical diagram of the automatic lifting and near-infrared spectrometer auxiliary guidance platform under the soil of the present invention; Figure 10 This is a schematic diagram of the working principle of the auxiliary guidance platform of the near-infrared spectrometer of the present invention; Figure 11 This is a working entity diagram of the auxiliary guidance platform of the near-infrared spectrometer of the present invention; Figure 12 It is a schematic diagram of the working principle of the automatic underground lifting platform of the present invention.

[0010] Reference numerals: 1. Visually assisted guidance of the landing platform; 2. Landing platform support frame; 3. Outer cylinder of the double-walled soil isolation rotating device; 301. Motor transmission gear; 302. Drive motor; 303. Inner cylinder near-infrared spectrum detection port; 304. Cylinder bottom rotating gear; 305. Inner cylinder support shaft; 306. Inner cylinder support plate; 4. Device storage box; 5. Inner cylinder of double-wall soil isolation rotating device; 6. Near-infrared spectrometer auxiliary guidance platform support frame; 7. Auxiliary guide platform for near-infrared spectrometer; 701. Rack guide rail; 702. Transmission gear; 703. Fixed clamp shaft; 704. Guide platform; 705. Drive motor; 8. Automatic underground lifting platform; 801. Drive motor; 802. Connector; 803. Threaded rod; 804. Fixing rod; 805. Fixing holes for threaded rod and fixing rod; 806. Fixing plate; 9. Near-infrared spectrometer; 10. Casting servo; 11. Automatic take-up wheel. DETAILED DESCRIPTION

[0011] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. After determining the target monitoring area, soil base stations are regularly installed at the required monitoring points according to the monitoring requirements. Figure 1 As shown, the soil base station is divided into two parts, above ground and underground. The part below the device storage box 4 is buried in the monitoring point that needs to be monitored. The above ground part mainly includes the device storage box 4, the visual auxiliary guidance landing platform 1 and its bracket 2. Figure 2 As shown, the device storage box 4 concentrates the battery power required for system maintenance and common soil sensors, which are used to collect temperature, humidity, light, organic matter, pH, nitrogen, phosphorus and potassium of the surface soil.

[0012] The main body of the base station is a double-walled soil isolation rotating device, which is divided into two parts: the outer cylinder 3 and the inner cylinder 5. Both the outer cylinder and the inner cylinder have a detection port on the side. The outer cylinder is a combination of a cylinder and a cone, and the inner cylinder is a cylinder with an opening at the top. Figure 3 In the non-working collection state, the two detection ports 303 are separated from each other to prevent soil powder from entering the inner cylinder structure.

[0013] The coordinates of the soil base station are input into the Raspberry Pi on the F450 open source transport drone. The drone is equipped with an M8NGPS module. Based on the location information provided by GPS, the transport drone will fly to the sky above the target base station with a near-infrared spectrometer and prepare for a fixed-point landing.

[0014] The gimbal mounted on the bottom of the drone adjusts the camera so that the camera captures the image of the ground, continuously lowers the flight altitude of the drone itself and begins to descend. The green dot in the center of the landing platform 1 is guided by visual assistance through the center positioning method. The basic implementation principle is: identify the green dot in the captured video stream, and continuously adjust the drone's posture so that the green dot in the video stream is in the center of the video. The visual recognition technology assists in guiding the transport drone to land. Figure 4 shown.

[0015] After a successful landing, the Raspberry Pi establishes a Bluetooth link with the ESP32 controller, controlling the dual-wall soil isolation rotating device to begin operation. As shown in Figure 5, the drive motor 302 begins to rotate, driving the motor transmission gear 301, which in turn drives the bottom rotation gear 304, thereby rotating the inner cylinder 5. After the inner cylinder rotates a certain angle, the detection ports 303 of the inner and outer cylinders align with each other.

[0016] The near-infrared spectrometer casting assembly then lowers the spectrometer onto the near-infrared spectrometer auxiliary guidance platform 7. The basic assembly structure is shown in Figure 6 and includes the near-infrared spectrometer 9, casting servo 10, and automatic reel 11. As shown in Figure 7, the near-infrared spectrometer casting assembly is mounted directly in front of the drone frame. The elastic line is drawn from the automatic reel 11, passed through the locking hole of the casting servo 10, and secured to the near-infrared spectrometer 9. The automatic reel draws a predetermined length of elastic line from the reel under load and automatically rewinds it back into the reel under no load. The casting servo 10 pushes the elastic line into the circular hole to lock the line. Once locked, the line will not be stretched beyond the reel.

[0017] During the flight, the elastic line is completely locked. After successfully landing on the platform, the elastic line is released and, under the action of the gravity of the near-infrared spectrometer, the elastic line begins to stretch until it completely lands on the near-infrared spectrometer auxiliary guidance platform 7.

[0018] As shown in Figure 8, the inner tube is equipped with a near-infrared spectrometer auxiliary guidance platform 7 and an automatic lifting platform 8 under the soil. Figure 9 shown.

[0019] The function of the near infrared spectrometer auxiliary guiding platform 7 is to push the spectrometer to the detection port 303. Its working principle is as follows: Figure 10 As shown, a driving motor 705 is installed under the platform. The rotation of the motor drives the transmission gear 702, and the gear engages with the rack guide 701 installed on the chassis. The rotation of the gear drives the platform to move forward or backward. Figure 11 This is a working entity diagram of the near-infrared spectrometer auxiliary guidance platform.

[0020] The working principle of the underground automatic lifting platform 8 is that a fixed plate 806 is placed perpendicular to the cylindrical base. A threaded rod 803 and two fixed rods 805 are mounted on the fixed plate. A drive motor 801 is installed at the bottom of the cylinder, connected to a threaded rod 803 via a connector 802. The motor rotates to drive the threaded rod, while the two fixed rods provide stability. The near-infrared spectrometer auxiliary guide platform 7 is equipped with screw holes. The threaded rod 803 passes through the screw holes. Rotation can drive the platform up or down, such as Figure 12 shown.

[0021] The entire detection process is as follows: the automatic lifting platform 8 under the soil will descend one unit according to the set unit depth, and then the near-infrared spectrometer auxiliary guidance platform 7 will push the spectrometer to the detection port 303, and the spectrometer will scan. After the scan is completed, the lifting platform will continue to descend one unit, and the above actions will be repeated until it reaches the bottom of the inner tube.

[0022] After the test is completed, the lifting platform rises to its initial position. During the upward movement, the elastic line on the automatic reel is unloaded. The line pulled during the descent is rewound back into the reel, and the casting servo 10 locks the elastic line. The drone executes the takeoff command and continues to transport the spectrometer to the next test location.

[0023] The system design of this invention takes into account the various needs and challenges of soil testing. Through high-precision near-infrared spectroscopy, it enables in-depth analysis and assessment of soil characteristics at all vertical levels. The entire process is highly automated, significantly improving the efficiency and accuracy of vertical soil layer testing.

Claims

1. A near-infrared spectroscopy vertical gradient soil layer detection device, characterized in that: It includes a soil near-infrared spectrum detection base station and a spectrometer transportation device; The soil near-infrared spectroscopy detection base station consists of a double-walled soil isolation rotating device, an automatic lifting platform under the soil, a near-infrared spectrometer auxiliary guidance platform, a visual auxiliary guidance landing platform, and a device storage box. The spectrometer transport device consists of a spectrometer transport drone, a near-infrared spectrometer throwing component and a spectrometer.

2. The soil detection device according to claim 1, characterized in that: The main body of the base station is a double-walled soil isolation rotating device. This device consists of an outer cylinder and an inner cylinder. The outer cylinder is a cylindrical body with an inverted conical shell at the bottom. The outer cylinder and the inner cylinder are separated by a certain gap. The main function is to separate the inner cylinder from the underground soil layer. The inner cylinder is a cylindrical shape with an open top and a rotating gear installed at the bottom; The driving motor drives the transmission gear and the rotating gear to rotate, thereby driving the entire inner cylinder to rotate along the central axis; A supporting shaft is provided at the bottom of the inner cylinder, and a supporting plate is installed at the lower end of the shaft, and the supporting plate contacts the inner wall of the cone of the outer cylinder; A detection auxiliary platform is installed in the inner tube, which mainly includes a near-infrared spectrometer auxiliary guidance platform and an automatic lifting platform under the soil.

3. The soil detection device according to claim 1, wherein: The underground automatic lifting platform is a one-dimensional up and down moving platform. The fixed plate is placed perpendicular to the cylindrical chassis. A threaded rod and two fixed rods are installed on the fixed plate. A driving motor is installed at the bottom of the cylinder, which is connected to a threaded rod through an adapter. The rotation of the motor can drive the threaded rod. Two fixed rods play a stabilizing role; Screw holes are installed on the auxiliary guide platform of the near-infrared spectrometer. The threaded rod passes through the screw holes. The rotation of the threaded rod can drive the platform to move upward or downward.

4. The soil detection device according to claim 1, characterized in that: The auxiliary guidance platform of the near-infrared spectrometer is a one-dimensional forward and backward moving platform. It relies on the rotation of the drive motor under the platform to drive the gear. The gear engages with the tooth pitch installed on the chassis. The rotation of the gear drives the platform to move forward or backward.

5. The soil detection device according to claim 1, characterized in that: The visual technology-assisted guidance platform has a circular surface consisting of a green inner circle and a blue outer circle. The drone lands within the green inner circle using the onboard gimbal camera and landing control program. A bracket is provided at the bottom of the visual technology-assisted guidance platform to provide support.

6. The soil detection device according to claim 1, characterized in that : The near-infrared spectrometer casting assembly is installed in front of the UAV frame. The assembly mainly includes a casting servo and an automatic reel. The elastic line is led out from the automatic reel, passes through the card hole of the casting servo, and is fixed on the near-infrared spectrometer. The automatic take-up reel can draw out a certain length of elastic line from the reel under load conditions, and automatically rewind the elastic line into the reel under no-load conditions. The casting servo can push the elastic line into the round hole to lock the elastic line. After locking, the length of the elastic line outside the reel will not be stretched.

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