Plant leaf reflectivity detector

Abstract

The invention discloses a plant leaf reflectivity detector, and aims to accurately measure the reflectivity of a plant leaf so as to evaluate the nitrogen content and guide scientific fertilization. The detector is composed of a main shell, an auxiliary shell, a main control board, a display module, an acquisition mechanism, a handheld shell and the like, an optical system is built through a mechanical structure system, an electrical control system controls AD acquisition, LED start and stop and optical filter wheel rotation, and reflectivity measurement is achieved. The uniquely designed optical filter wheel is made of aluminum alloy, so that the stable operation of the system is ensured; the shell is made of resin materials, so that protection performance is improved, and portability is achieved. The operation process comprises the steps of startup initialization, zero calibration, measurement of a standard whiteboard and plant leaves, and data query and analysis. In addition, the detector has maintenance measures such as regular cleaning, battery maintenance and safe storage, and long-term stable operation is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural technology, in particular to a high-precision and portable plant leaf reflectance detector. The detector can quickly and accurately measure the reflectance of plant leaves by integrating advanced optical systems and electrical control systems, providing a scientific basis for precision agricultural fertilization. BACKGROUND

[0002] Nitrogen is an essential nutrient element for plant growth, playing a crucial role in plant growth and development, yield formation, and quality improvement. However, excessive nitrogen fertilizer not only increases the cost of agricultural production, but also may cause environmental pollution and ecological damage.

[0003] Therefore, reasonable application of nitrogen fertilizer and accurate determination of nitrogen content in plants are of great significance for improving crop yield and protecting the ecological environment.

[0004] In traditional methods, the measurement of plant leaf reflectance often relies on non-professional equipment, which often has problems such as inaccurate measurement and complex operation. Although some reflectance measurement methods are disclosed in the prior art, they lack the support of professional detection equipment, especially the construction of optical systems is not accurate enough, resulting in unstable and unreliable measurement results. Therefore, it is an urgent need in the current agricultural technology field to develop a high-precision and portable plant leaf reflectance detector. SUMMARY

[0005] The present application aims to provide a high-precision and portable plant leaf reflectance detector, which can quickly and accurately measure the reflectance of plant leaves by accurately constructing an optical system and combining an advanced electrical control system, providing a scientific basis for precision agricultural fertilization.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solution: a plant leaf reflectance detector, comprising a main shell, a secondary shell, a main control board, a display module, a top cover, a handheld shell and a collection mechanism. The specific technical solution is as follows:

[0007] The main shell and the secondary shell are made of high-strength white resin material, and the surface is respectively sprayed with yellow and white light oil treatment, increasing the protection performance and aesthetic degree.

[0008] The secondary shell is assembled and formed with the main shell through a precisely designed limiting clamping groove, and is fixedly connected through high-strength locking screws, ensuring the stability and reliability of the structure.

[0009] The main control board is fixed inside the main shell and connected through a precise screw through hole, and is electrically connected with a high-speed on-board USB 3.0 module, facilitating fast data transmission and sharing.

[0010] The display module includes a high-definition display screen cover, a display screen, a wiring hole and a membrane switch, and is fixed to the other side of the main shell by waterproof locking screws, and is used for intuitively displaying measurement data and an operation interface.

[0011] The collection mechanism is arranged inside the auxiliary shell and includes a high-brightness LED lamp bead, a multi-waveband filter, a precision filter wheel, a high-sensitivity photodiode, a plano-convex lens, a high-speed motor, a motor base, a lens seat, a speed reducer, a Hall encoder and a high-density PCB.

[0012] The motor is fixed on the motor base and is connected to the filter wheel through a high-precision shaft transmission.

[0013] The photodiode is installed on a support inside the auxiliary shell, and the plano-convex lens is installed in the lens seat, which is fixed in the middle through hole of the auxiliary shell.

[0014] The electrical control system is highly integrated on the main control board, and a high-performance DSP is used as the main control chip to realize real-time data collection, processing, storage and display.

[0015] The system has an automatic calibration function and can automatically adjust the brightness of the LED lamp bead and the position of the filter wheel according to the change of the ambient light to ensure the accuracy and stability of the measurement results.

[0016] The technical progress and beneficial effects of the present application are as follows:

[0017] The technical progress is as follows:

[0018] 1. Precise construction of optical system:

[0019] Innovation: Through the relative position relationship between the precision designed plano-convex lens and the photodiode, and the rotatable filter wheel, the precise construction of the optical system is realized.

[0020] This design overcomes the problem of inaccurate construction of the optical system of traditional detection equipment, and significantly improves the accuracy of reflectance measurement.

[0021] Effect: It ensures that after the light is reflected by the standard white board or plant leaves, it can be accurately focused and pass through the filter of a specific waveband, and finally irradiate on the photodiode to obtain more accurate reflectance data.

[0022] 2. Filter wheel design and material selection:

[0023] Innovation: The filter wheel is made of aluminum alloy material and is blackened on the surface, which not only ensures the rigidity of the structure but also reduces the weight, and reduces the reflection and scattering of light.

[0024] Effect: Improved the overall operation stability of the system, reduced measurement errors, and made reflectivity data more reliable.

[0025] 3. Integration of electrical control systems:

[0026] Innovation: Integrating key electrical components such as the motor drive board and LED driver on the control board simplifies circuit design and reduces the space required for the control board and motor driver.

[0027] Effect: Improved system integration and reliability, reduced failure rate, and facilitated equipment maintenance and upgrades.

[0028] 4. Portable design and handheld operation:

[0029] Innovation: The whole device adopts a portable design, and the limit connection setting between the handheld shell and the battery compartment cover makes it easy for users to carry and use.

[0030] Effect: The application scenarios of the equipment have been expanded. Users can perform real-time measurements in outdoor environments such as fields, improving work efficiency.

[0031] The beneficial effects are as follows:

[0032] 1. Improve measurement accuracy:

[0033] Through precise optical system construction and electrical control system integration, the measurement accuracy of plant leaf reflectivity has been significantly improved, providing reliable data support for the assessment of nitrogen content.

[0034] 2. Reduce the difficulty of operation:

[0035] The portable design and handheld operation mode make it easy for users to get started and perform measurements without professional training, reducing the difficulty and threshold of operation.

[0036] 3. Enhance equipment durability:

[0037] The shell material is made of resin and is oil-sprayed, which increases the protection performance of the equipment and enables the equipment to operate stably for a long time in harsh outdoor environments.

[0038] 4. Promote precision agricultural fertilization:

[0039] By measuring the reflectivity of plant leaves in real time and evaluating the nitrogen content, it provides farmers with a scientific basis for fertilization, helps achieve precision agricultural fertilization, and improves crop yield and quality.

[0040] 5. Reduce production costs and environmental pollution:

[0041] Precision fertilization reduces the overuse of nitrogen fertilizer, reduces the cost of agricultural production, and reduces environmental pollution and ecological damage, which has good economic and social benefits. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 It is a structural schematic diagram of the present application;

[0043] Figure 2 It is an exploded view of the structure of the present application;

[0044] Figure 3 It is a structure effect diagram of the present application;

[0045] Figure 4 It is a sectional view of the collection mechanism of the present application;

[0046] Figure 5 It is a flat convex lens structure installation diagram of the present application;

[0047] Figure 6 It is a structure schematic diagram of the filter wheel of the present application;

[0048] Figure 7 It is a motor structure installation diagram of the present application;

[0049] Figure 8 It is a LED lamp bead structure installation diagram of the present application;

[0050] Figure 9 It is a main shell and auxiliary shell structure installation diagram of the present application;

[0051] Figure 10 It is a on-board USB 3.0 module structure installation diagram of the present application;

[0052] Figure 11 It is a display module structure schematic diagram of the present application;

[0053] Figure 12 It is a circuit control system schematic diagram of the present application;

[0054] Figure 13 It is a circuit system wiring schematic diagram of the present application;

[0055] Figure 14 It is a system control flow chart of the present application;

[0056] Figure 15 It is a display schematic diagram of the operation panel of the present application.

[0057] In the figure: 1 main shell, 2 auxiliary shell, 3 main control board, 4 display module, 5 top cover, 6 splicing plate, 7 limit slot, 8 locking screw, 9 collection mechanism, 10 on-board USB 3.0 module, 11 handheld shell, 12 battery, 13 battery compartment cover, 14 interface.

[0058] 401 display screen cover, 402 display screen, 403 wiring hole, 404 thin film switch;

[0059] 901 LED lamp bead, 902 optical filter, 903 optical filter wheel, 904 photodiode, 905 plano-convex lens, 906 motor, 907 motor base, 908 lens seat, 909 speed reducer, 910 Hall encoder, 911 PCB board. DETAILED DESCRIPTION

[0060] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0061] Please refer to Figures 1-15 The present application provides a technical solution: a plant leaf reflectivity detector, comprising a main shell 1, a secondary shell 2, a main control board 3, a display module 4 and a top cover 5, the main shell 1 is provided with a secondary shell 2 on one side, a splicing plate 6 on the secondary shell 2 is provided with a limiting clamping groove 7 on the surface, the secondary shell 2 and the main shell 1 are spliced and installed into shape through the limiting clamping groove 7, and are fixedly connected between them through locking screws 8, and the inside of the secondary shell 2 is provided with a collection mechanism 9;

[0062] As a preferred scheme, the main shell 1 and the secondary shell 2 are both made of white resin, the surface of the main shell 1 is treated by spraying yellow light oil, and the surface of the secondary shell 2 is treated by spraying white light oil, so as to increase the protection performance, when the main shell and the secondary shell are installed, they are spliced through the reserved limiting clamping groove 7, and then fixed by two locking screws 8;

[0063] Specifically, the inside of the main shell 1 is provided with a main control board 3, the main control board 3 is fixedly connected with the main shell 1 through a screw through hole, and a board-mounted USB 3.0 module 10 is electrically connected on one side of the main control board 3, and an interface 14 on the board-mounted USB 3.0 module 10 is opened on the side surface of the main shell 1;

[0064] As a preferred scheme, the board-mounted USB 3.0 module 10 is installed in the main shell 1 through two screws, and the gap between the USB female head and the main shell is filled with silicone rubber for waterproof sealing treatment, and the interface 14 is used for the purpose of facilitating the sharing of internal data of the detector with the outside;

[0065] Specifically, the other side of the shell 1 is provided with a display module 4, the display module 4 includes a display screen cover 401, a display screen 402, a wiring hole 403 and a membrane switch 404, the display screen cover 401 is fixedly installed on the main shell 1 through locking screws 8, the display screen 402 is installed on the display screen cover 401, the wiring hole 403 is opened on the display screen cover 401, and the membrane switch 404 is pasted on the display screen cover 401 through back adhesive, the material of the display screen cover 401 is white resin, and the surface is treated by spraying yellow gloss oil;

[0066] Specifically, the upper side of the main shell 1 is provided with a top cover 5, and the top cover 5 is fixedly connected with the main shell 1 through locking screws 8.

[0067] Specifically, the lower side of the main shell 1 is provided with a handheld shell 11, the inside of the handheld shell 11 is provided with a battery 12, and the surface of the handheld shell 11 is provided with a battery compartment cover 13 in position connection.

[0068] Specifically, the collection mechanism 9 includes LED lamp beads 901, a filter 902, a filter wheel 903, a photodiode 904, a plano-convex lens 905, a motor 906, a motor seat 907, a lens seat 908, a speed reducer 909, a Hall encoder 910 and a PCB board 911.

[0069] Specifically, the motor 906 is fixedly installed on the motor seat 907, the motor seat 907 is fixedly installed on the inner bottom surface of the secondary shell 2 through a countersunk screw, the material of the motor seat 907 is aluminum, the surface is treated by blackening, the front side of the motor 906 is provided with the speed reducer 909, the rear side is provided with the Hall encoder 910, the shaft of the motor 906 is in transmission connection with the filter wheel 903, the filter wheel 903 is provided with the filter 902, the filter 902 is provided with a plurality of, in the embodiment, eight filters 902 are provided and are arranged in a circular array on the filter wheel 903, the material of the filter wheel 903 is aluminum, the surface is treated by blackening, the inner side of the filter wheel 903 is provided with the photodiode 904, the photodiode 904 is installed on the support in the secondary shell 2, the outer side of the filter wheel 903 is provided with the plano-convex lens 905, the plano-convex lens 905 is installed in the lens seat 908, the material of the lens seat 908 is white resin, the surface is treated by spraying black matte oil, the lens seat 908 is fixedly arranged at the middle through hole of the secondary shell 2, the LED lamp beads 901 are arranged above the through hole, and the LED lamp beads 901 are fixedly installed on the secondary shell 2 through the PCB board 911.

[0070] The plano-convex lens 905 is installed in the lens seat 908, and is fixed by adding epoxy resin or urethane adhesive in the reserved glue injection hole. The lens module is fixed to the sub-housing by 502 glue. The filter wheel 903 is made by machining, and is made of 6061-T4 aluminum material with black surface treatment. The filter is glued on the outer circular side of the filter using UV glue, and 8 filters are installed and fixed on the filter wheel. After the filter wheel module is installed with the motor shaft, it is fixed by screwing the jackscrew. The LED lamp beads 901 are welded on the PCB board 911, and a proper amount of white silicone rubber is coated for waterproof sealing.

[0071] As a preferred solution, the motor is controlled to rotate the filter wheel at a constant speed. When the effective light aperture of the filter coincides with the effective aperture of the lens, the LED lamp beads of the corresponding waveband of the filter begin to illuminate, and the on-board AD module collects the corresponding current value. The current values of the 8 filters are sequentially collected.

[0072] The electrical control system mainly controls the stepping motor, LED, AD acquisition, data display and storage. In order to simplify the circuit and reduce the space volume of the control board and motor driver, the motor drive board is integrated on the control board, and the LED driver is welded on the bottom of the LED. The entire electrical control system is independently programmable, and the control loop integrates acquisition chips, operational amplifier circuits, communication circuits, etc. inside, mainly realizing data acquisition and storage functions, checking the status of Flash and data display, and completing corresponding functions.

[0073] In order to better view the functions of the entire system, the MCU uses DSP as the main control chip of the entire system. The brightness of the LED is controlled by PWM wave. AD chips, photodiodes and other modules are used to collect data, and Flash is used to directly save the sampled data, and the data collected by each filter wheel is displayed through the LCD.

[0074] After the system is powered on, it is reset, including the initialization of each module, filter wheel zero calibration and other operations. Then prepare to start collecting data, at this time the motor starts to rotate, waits for the filter and lens to coincide, turns on the LED of the corresponding wavelength, and the AD collects the voltage value. After this collection is completed, the data is saved in the Flash, and the next filter and lens coincidence is waited for again, and the above operation is repeated again. Directly this test is completed.

[0075] Zero calibration

[0076] The motor module equipped with the filter wheel is installed on the zero calibration seat by using 4 M3 screws, and the filter wheel is assembled by using the positioning pin passing through the hole of the zero calibration seat and the filter wheel, the corresponding angle of the Hall encoder is read, the positioning pin is taken out, a filter numbered 1 is installed, the number, the filter band and the angle value displayed by the Hall encoder are recorded, the filter wheel is rotated clockwise, the filters numbered from 2 to 8 are sequentially installed, and the record is made.

[0077] The power consumption of the whole mechanism (LED lamp constant state) is estimated to be 15W, the power supply voltage is set to 12V, the battery capacity required for continuous work of 30min / h is

[0078] Battery capacity = (load power consumption * time) / (battery voltage * conversion rate)

[0079] = (15W * 0.5h) / (12V * 95%)

[0080] = 2.193Ah

[0081] = 2193mAh

[0082] In the specific implementation of the present application: press the "power" button to start and enter the instruction page, tell the user the meaning and content represented by each data in the display interface, continue to press the "confirm" key to enter the display interface, then press the "reset" button to correct the initial position of the filter wheel based on the data of the zero calibration of the filter wheel, and re-measure the whiteboard data. Next, put the standard whiteboard into the field of view of the detector, press the "test" button to measure the standard whiteboard, replace the whiteboard with a leaf, press the "confirm" button to enter a new display page, continue to press the "test" button to measure the energy returned by the leaf, and each measurement of the energy of the leaf is a group of data. When measuring multiple times, the "up" and "down" page buttons can be used to query each group of data. Figure 15 The operation panel of the detector is selected from a thin film switch, which is attached to the display screen housing through the back glue of the panel, the 'power' button is responsible for the total power supply switch of the equipment, the'reset' button is responsible for rotating the filter wheel back to the initial position, the 'test' button is responsible for starting the detector to measure the returned energy of the whiteboard and the leaf, and the 'up' and 'down' page buttons are responsible for viewing the data collected multiple times.

[0083] Working principle

[0084] The light source (LED lamp bead) emits light of each wave band, irradiates on the standard white board, the light enters the plano-convex lens after being reflected by the standard white board, and is filtered through the optical filter, and finally irradiates on the photodiode to collect the corresponding current value. Similarly, the standard white board is replaced by the plant leaf, and the corresponding current value is collected (note: the distance between the detector and the standard white board and the leaf should be kept consistent during each collection). The data collected twice is analyzed and calculated, and finally the reflectivity of the leaf is obtained. Figure 3 The working effect mode of the detector at different distances from the measured object is detected.

[0085] Further elaborate assembly process: main shell and vice shell assembly:

[0086] The main shell 1 and the vice shell 2 are spliced through the precisely designed limiting slot 7 to ensure accurate alignment. High-strength locking screws 8 are used to pass through the screw holes on the main shell and the vice shell to firmly fix them together.

[0087] Check whether the waterproof sealing ring at the connection between the main shell and the vice shell is intact to ensure that no moisture penetrates.

[0088] Main control board installation: the high-performance main control board 3 is fixedly connected with the main shell 1 through a precise screw hole to ensure that the main control board is stable and not loose. The USB 3.0 module 10 is connected to the main control board 3, and the module is fixed on the designated position on the side of the main shell 1 through two screws. Silicon rubber is filled in the gap between the USB female head and the main shell for waterproof sealing treatment.

[0089] Display module installation: the high-definition display screen cover 401 is fixed on the other side of the main shell 1 through the waterproof locking screw 8 to ensure that the display screen cover is flat and not skewed. The high-definition display screen 402 is installed on the display screen cover 401, the signal line connecting the display screen and the main control board 3 is connected, and the signal transmission is stable. The wiring hole 403 is opened on the display screen cover 401 for arranging and fixing the signal line to prevent clutter. The membrane switch 404 is pasted on the display screen cover 401 through the back high-viscosity back glue to ensure accurate switch position and flexible operation.

[0090] Collection mechanism installation: the motor seat 907 is installed inside the vice shell 2, and is firmly fixed on the inner bottom surface by using a countersunk screw.

[0091] The high-speed motor 906 is installed on the motor seat 907, and the reducer 909 and the Hall encoder 910 are connected to the corresponding positions of the motor. The precise optical filter wheel 903 is connected to the motor 906 through the motor shaft transmission to ensure stable rotation of the filter wheel without jamming.

[0092] Multi-band filters 902 are installed in a circular array on the filter wheel 903 and fixed with filter UV glue to ensure that the filter position is accurate and not easy to fall off. A high-sensitivity photodiode 904 is installed on the internal bracket of the sub-shell 2 to ensure that it can accurately receive the light after passing through the filter and the plano-convex lens. The lens seat 908 is fixed at the middle through hole of the sub-shell 2, and the plano-convex lens 905 is installed in the lens seat, and fixed with epoxy resin or Ulidan adhesive to ensure that the lens position is stable and the light path is accurate. A high-brightness LED lamp bead 901 is installed above the lens seat 908, fixed to the sub-shell 2 through the PCB board 911, and coated with an appropriate amount of white silicone rubber for waterproof sealing.

[0093] Handheld housing and battery installation: Install the high-capacity rechargeable battery 12 into the handheld housing 11, ensuring that the positive and negative poles of the battery are connected correctly. A waterproof battery compartment cover 13 is provided on the surface of the handheld housing 11 to ensure that the battery compartment cover is well sealed and easy to open.

[0094] Top cover installation: Fix the top cover 5 on top of the main housing 1 with the waterproof locking screws 8, ensuring that the top cover is flat and not skewed.

[0095] Check whether the heat dissipation holes on the surface of the top cover 5 are unobstructed to ensure that the internal components can dissipate heat well.

[0096] Operation process

[0097] Boot and initialization:

[0098] Press the "Power" button to turn on the detector and enter the initialization state. The system automatically resets and calibrates each module.

[0099] After initialization is complete, the system displays a welcome interface and operation guide, prompting the user to proceed to the next step.

[0100] Zero calibration: Place the detector on a stable level surface to ensure there is no interference from external light.

[0101] Press the "Reset" button, the system enters the zero calibration state, and the motor 906 drives the filter wheel 903 to rotate to the initial position.

[0102] Use the positioning pin to pass through the zero calibration seat and any filter assembly hole on the filter wheel, read the angle value corresponding to the Hall encoder 910 and record it.

[0103] Install and number the remaining filters in sequence, record the wavelength of each filter and the angle value displayed by the Hall encoder, and use the encoder angle value corresponding to the filter numbered 1 as the zero position.

[0104] Measuring a standard white plate: Place a standard white plate in the detector's field of view and ensure that the surface of the white plate is flat and free of scratches.

[0105] Press the "Test" button, the system starts measuring the reflectance of the standard whiteboard, LED light beads 901 emit light and pass through the optical filter 902 and the plano-convex lens 905 to irradiate the photodiode 904. The photodiode 904 converts the received light signal into an electrical signal and transmits it to the main control board 3 for data processing and storage.

[0106] The system displays the reflectance measurement results of the standard whiteboard and prompts the user to proceed to the next step.

[0107] Measure the plant leaves: Replace the standard whiteboard with the plant leaves to be measured, ensuring that the leaf surface is dry and free of stains.

[0108] Press the "Test" button, the system starts measuring the reflectance of the plant leaves, the operation process is the same as measuring the standard whiteboard.

[0109] The system displays the reflectance measurement results of the plant leaves and prompts the user whether to save the data or proceed to the next measurement.

[0110] Data query and analysis: When measuring multiple times, the user can use the "up" and "down" page buttons to query each set of measurement data.

[0111] The system has built-in data analysis tools, users can further process and analyze the measurement data, such as calculating the mean, standard deviation, etc. Users can also transmit measurement data in real time to smart phones, tablets and other terminal devices through wireless communication modules for further analysis and processing.

[0112] Maintenance and maintenance

[0113] Regular cleaning: Use soft cloth to wipe the detector housing and display screen surface, avoid using chemical cleaners or hard objects to scratch. Regularly clean the optical elements inside the collection mechanism, such as plano-convex lenses, optical filters, etc., to ensure that their surfaces are clean and free of stains.

[0114] Battery maintenance: Regularly check the battery level and charge in time to ensure the normal operation of the detector.

[0115] When not in use for a long time, the battery should be fully charged and stored in a dry and cool place to avoid damage caused by self-discharge.

[0116] Storage and carrying: The detector should be stored in a special carrying case to avoid being squeezed and collided.

[0117] System calibration and debugging

[0118] Optical system calibration:

[0119] Light source calibration: In a darkroom environment, start the detector, and let the LED beads 901 emit light of each waveband. After reflection by the standard white board, use the external high-precision spectrometer to detect the wavelength and intensity of the reflected light, and compare it with the data collected by the built-in photodiode 904. If there is a deviation, adjust the driving current or color temperature adjustment parameters of the LED beads 901 for fine tuning to ensure the accuracy and stability of the light source output.

[0120] Filter calibration: Use a monochromatic light source with known wavelength to irradiate each filter 902 on the filter wheel 903 in turn, and detect the light intensity transmitted through the filter by the photodiode 904. Compare it with the theoretical transmittance. If the deviation exceeds the allowed range, clean or replace the filter to ensure that the transmittance of each filter meets the design requirements.

[0121] Lens focusing calibration: Use a standard point light source to adjust the relative distance between the plano-convex lens 905 and the photodiode 904. By observing the maximum value of the photodiode output signal, determine the best focusing position. Fix the lens holder 908 to ensure consistent focusing state of the lens during each measurement.

[0122] Electrical system debugging:

[0123] Motor control debugging: Control the start, stop, forward and reverse rotation, and speed adjustment of the motor 906 through programming, and observe whether the rotation of the filter wheel 903 is smooth and accurate. Use the feedback signal of the Hall encoder 910 to accurately control the switching time of the filter, ensuring that each filter can stay at the predetermined position for the photodiode to collect data.

[0124] AD acquisition debugging: Simulate input of light signals with different intensities to the photodiode 904, and check whether the AD acquisition module can accurately and quickly convert them into digital signals. Adjust the gain and bias parameters of AD acquisition to cover the possible changes in light intensity during actual measurement while ensuring the accuracy of acquisition.

[0125] Data display and storage debugging: Display the collected reflectance data on the LCD display screen 402 to check whether the display content is clear and accurate. At the same time, store the data in the Flash memory to verify whether the read and write functions of the data are normal, and ensure that the measurement data will not be lost.

[0126] Whole system debugging: The optical system and electrical system are jointly debugged to simulate the actual measurement process. First, measure the standard whiteboard and record the reflectivity data; then replace it with plant leaves and repeat the measurement process. Compare the two measurement results to analyze the stability and accuracy of the system. If abnormal data is found, check if the optical elements are loose and the electrical connection is reliable, and troubleshoot and repair the problem. Repeat the measurement several times, calculate the standard deviation and coefficient of variation of the measurement data, and evaluate the repeatability and precision of the system. According to the statistical results, optimize and adjust the system to further improve the reliability of the measurement results.

[0127] Usage notes

[0128] Environmental requirements:

[0129] The detector should be used in a dry, non-corrosive gas-free, and temperature suitable (generally recommended between 0°C-40°C) environment. Avoid operating in harsh environments such as high temperature, high humidity, strong electromagnetic interference, etc. to avoid affecting the performance of the equipment and the accuracy of the measurement results.

[0130] When used outdoors, try to avoid direct sunlight on the detector to prevent light interference from causing measurement errors. You can choose to measure in the shade or use an umbrella.

[0131] Operation specification:

[0132] Before measurement, make sure that all parts of the detector are securely installed and that the optical element surface is clean and free of stains. In particular, the plano-convex lens 905 and the filter 902 should be cleaned with special cleaning tools and cleaning fluid if there are dust or fingerprints.

[0133] During measurement, keep the distance between the detector and the measured object (standard whiteboard or plant leaves) stable and avoid shaking. At the same time, make sure the surface of the measured object is flat, wrinkle-free or damaged to avoid affecting the uniformity of the reflected light.

[0134] After each measurement is completed, turn off the power of the detector in time to avoid overheating of the equipment or excessive consumption of battery power. If the detector is not used for a long time, remove the battery and store it in a dry, cool place.

[0135] Maintenance:

[0136] Regularly maintain the detector and check if the connections of all parts are loose. If they are loose, tighten them in time. Check the battery level and usage, and replace the battery if its performance has declined.

[0137] Every certain period of time (recommended every 3-6 months), the detector is calibrated and debugged comprehensively to ensure the performance of the optical system and the electrical system is always in the best state. You can contact professional maintenance personnel or equipment suppliers for calibration services.

[0138] Troubleshooting

[0139] Cannot start up:

[0140] Check if the battery is installed correctly and if the battery has enough power. If the battery power is insufficient, charge it in time or replace a new battery.

[0141] Check if the power switch is damaged. Try pressing the power switch several times to see if it can start normally. If the power switch is damaged, replace a new power switch.

[0142] Measurement data is abnormal:

[0143] Check if the optical elements are contaminated or damaged. If there are stains or scratches on the plano-convex lens 905 or the filter 902, clean or replace them.

[0144] Check if the electrical connection is loose, especially the connection between the photodiode 904 and the main control board 3. If the connection is loose, replug the connection line to ensure reliable connection.

[0145] Check if the AD acquisition module is working normally. You can simulate the input light signal by connecting an external signal source and observe if the output of the AD acquisition module is consistent with the input signal. If the AD acquisition module is faulty, replace a new module.

[0146] Filter wheel rotation is abnormal:

[0147] Check if the motor 906 is working normally. You can judge by listening to the running sound of the motor or observing the rotation of the motor. If the motor is faulty, replace a new motor.

[0148] Check if the reducer 909 and the Hall encoder 910 are installed correctly and connected reliably. If the reducer or the Hall encoder has a problem, reinstall or replace a new component.

[0149] Check if the filter wheel 903 is stuck. It may be due to improper installation of the filter or foreign matter entering. Carefully check the filter wheel, remove the foreign matter, and reinstall the filter.

[0150] Through the above specific embodiments, the plant leaf reflectance detector of the present application can realize high-precision and stable plant leaf reflectance measurement, providing strong technical support for nitrogen content evaluation and precision fertilization in agricultural production. At the same time, reasonable use, maintenance and care methods can prolong the service life of the equipment and ensure that the equipment is always in good working condition.

[0151] While embodiments of the application have been shown and described, it is to be understood that the application is not limited to the details of the embodiments described, since numerous changes, modifications, substitutions and variations can be made thereto without departing from the spirit and scope of the application as defined by the appended claims and their equivalents.

Claims

1. A plant leaf reflectivity detector, comprising a main housing, a secondary housing, a main control board, a display module, and a top cover, characterized in that: A secondary shell is provided on one side of the main shell, and the secondary shell and the main shell are spliced ​​and assembled by precision limit slots and fixedly connected by high-strength locking screws; a high-precision acquisition mechanism is provided inside the secondary shell; a high-performance main control board is provided inside the main shell; a high-definition display module is provided on the other side of the main shell; a top cover is provided above the main shell; a portable handheld shell is provided below the main shell, a high-capacity battery is provided inside the handheld shell, and a waterproof battery compartment cover is provided on the surface of the handheld shell in a limit connection.

2. The plant leaf reflectivity detector according to claim 1, characterized in that: The acquisition mechanism includes high-brightness LED lamp beads, multi-band filters, a precision filter wheel, a high-sensitivity photodiode, a plano-convex lens, a high-speed motor, a motor base, a lens base, a reducer, a Hall encoder and a high-density PCB board; the high-speed motor is fixed on the motor base and connected to the precision filter wheel through a high-precision shaft drive; a circular array on the precision filter wheel is provided with filters of no less than 8 specific bands.

3. The plant leaf reflectivity detector according to claim 2, characterized in that: A high-sensitivity photodiode is provided on the inner side of the precision filter wheel and is installed on the internal bracket of the auxiliary shell; a plano-convex lens is provided on the outer side and is installed in the lens seat; the lens seat is fixed at the middle through hole of the auxiliary shell, and a high-brightness LED lamp bead is precisely set on the top.

4. The plant leaf reflectivity detector according to claim 1, characterized in that: The high-performance main control board is fixedly connected to the main shell through precision screw holes and is electrically connected to a high-speed onboard USB 3.0 module. The interface on the high-speed onboard USB 3.0 module is opened on the side of the main shell to facilitate fast data transmission.

5. The plant leaf reflectivity detector according to claim 1, characterized in that: The high-definition display module includes a high-definition display screen cover, a display screen, a wiring hole and a membrane switch. The high-definition display screen cover is fixed to the main housing by waterproof locking screws. The display screen is installed on the high-definition display screen cover for intuitively displaying measurement data. The membrane switch is adhered to the high-definition display screen cover by a high-viscosity adhesive on the back for easy operation.

6. The plant leaf reflectivity detector according to claim 2, characterized in that: The high-speed motor seat is made of high-strength aluminum, the surface is blackened to reduce reflection, and is fixed on the bottom surface of the auxiliary shell; a high-precision reducer is installed on the front side of the high-speed motor, and a Hall encoder is installed on the rear side for accurately controlling the motor speed and position.

7. The plant leaf reflectivity detector according to claim 2, characterized in that: The precision filter wheel is made of lightweight, high-strength aluminum, with a blackened surface to reduce stray light interference. It is manufactured through mechanical processing and has 8 to 16 filters of specific bands arranged in a circular array to meet different measurement requirements.

8. The plant leaf reflectivity detector according to claim 1, characterized in that: The main shell and the auxiliary shell are both made of high-strength white resin, and the surfaces are sprayed with yellow and white varnish respectively to increase the protection performance and aesthetics; at the same time, a waterproof sealing ring is provided at the connection between the main shell and the auxiliary shell to prevent moisture from penetrating and damaging the internal components.

9. The plant leaf reflectivity detector according to claim 1, characterized in that: The portable handheld housing is provided with a high-capacity rechargeable battery inside, and a waterproof battery compartment cover is provided on the surface limit connection to facilitate battery replacement and maintenance; at the same time, the surface of the handheld housing is provided with an anti-slip texture to increase the grip stability.

10. The plant leaf reflectance detector according to any one of claims 1 to 9, characterized in that: The electrical control system is highly integrated on a high-performance main control board, adopts a high-performance DSP as the main control chip, integrates a high-speed AD acquisition chip, a large-capacity memory, a high-definition display driver circuit and a high-speed communication interface circuit, and realizes real-time data acquisition, processing, storage and display.

11. The plant leaf reflectivity detector according to claim 10, characterized in that: The electrical control system also has an automatic calibration function, which can automatically adjust the brightness of LED lamp beads and the position of the filter wheel according to changes in ambient light to ensure the accuracy and stability of the measurement results; at the same time, the system has a built-in self-diagnostic program that can monitor the working status of each component in real time and prompt fault information.

12. The plant leaf reflectivity detector according to claim 2, characterized in that: The high-brightness LED lamp beads adopt a multi-chip integrated design to emit uniform and stable light; the multi-band filter adopts high-precision interference filtering technology to ensure that the transmittance of light in each band is consistent and the stray light interference is small.

13. The plant leaf reflectivity detector according to claim 2, characterized in that: The high-sensitivity photodiode adopts a back-illuminated structure to improve the photocurrent conversion efficiency; the plano-convex lens is made of low-dispersion glass material to reduce the influence of aberration on the measurement result.

14. The plant leaf reflectivity detector according to claim 1, characterized in that: The top cover is fixedly connected to the main shell by waterproof locking screws. The surface of the top cover is provided with heat dissipation holes to facilitate heat dissipation of internal components. At the same time, shock-absorbing material is provided inside the top cover to reduce the impact of vibration on the measurement results.

15. The plant leaf reflectivity detector according to claim 1, characterized in that: The plant leaf reflectivity detector is also equipped with a wireless communication module that supports multiple communication protocols such as Wi-Fi and Bluetooth, making it easy to transmit measurement data in real time to terminal devices such as smartphones and tablets for further analysis and processing.

16. The plant leaf reflectivity detector according to claim 1, characterized in that: The operating interface of the plant leaf reflectivity detector adopts a graphical design, which is simple and intuitive; at the same time, the system has built-in multiple measurement modes and data analysis tools to meet the measurement needs of different users.

17. The plant leaf reflectivity detector according to claim 1, characterized in that: The shell design of the plant leaf reflectivity detector complies with ergonomic principles and is comfortable to hold. At the same time, the surface of the shell is anti-slip treated to increase grip stability and prevent slipping and damage during use.

18. The plant leaf reflectivity detector according to claim 1, characterized in that: The plant leaf reflectance detector is also equipped with a portable carrying case for easy carrying and storage by users; a customized foam pad is provided inside the carrying case to fix the various components of the detector to prevent collision damage during transportation.

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