Device and Method for Detecting Chlorophyll Content in Living Plant Leaves

Abstract

The present invention provides a device and method for detecting the chlorophyll content of living plant leaves. The device includes a spectral data acquisition module, a ranging module, an image acquisition module, and a main control processing module. The spectral data acquisition module includes a spectral sensor, which is used to collect spectral data of the to-be-detected leaves. The ranging module includes at least one ranging sensor, which is used to collect distance data between the sensor and the to-be-detected leaves. The image acquisition module includes a camera, which is used to collect the leaf surface image of the to-be-detected leaves. The main control processing module is used to receive the data information of the to-be-detected leaves collected by the spectral data acquisition module, the ranging module, and the image acquisition module, and determine the chlorophyll content of the to-be-detected leaves based on the data information of the to-be-detected leaves. It can be applied to the detection of living plant leaves, reduce the influence of plant leaf inclination and leaf surface texture characteristics on the accuracy of reflectivity, and improve the accuracy of chlorophyll content detection.

Description

Technical Field

[0001] The present invention relates to the technical field of chlorophyll analysis, and particularly relates to a device and method for detecting the chlorophyll content of living plant leaves. Background Art

[0002] Chlorophyll is the main pigment for plants to carry out photosynthesis. It is located on the thylakoid membrane of plant cells and plays a core role in the light absorption process of photosynthesis. Therefore, the chlorophyll content and its changes can well reflect the photosynthesis ability, growth and health status of plants, etc., and have important significance in monitoring the growth trend, pests and diseases, crop yield, and predicting the maturity period of crops.

[0003] The traditional method for measuring chlorophyll content is mainly spectrophotometry. Although this method can accurately measure the chlorophyll content, it is labor-consuming, takes a long time to measure, and is destructive to plant leaves. With the development of spectral technology, scholars at home and abroad have begun to explore and study the relationship between chlorophyll in plant leaves and their spectral information and achieved good results. The possibility of non-destructively measuring leaf chlorophyll using spectral technology has been verified, and many spectral detection instruments for obtaining chlorophyll content information of field crops have been developed.

[0004] However, living crop leaves often have an unfixed leaf inclination angle. When the existing spectral detection instruments measure the leaf reflectance, due to the inclination of crop leaves, the reflected light amplitude cannot be fully obtained. On the other hand, different crop leaf surface texture structures have different reflections on light, and both jointly affect the accuracy of reflectance, ultimately affecting the accuracy of chlorophyll content prediction.

[0005] Therefore, how to provide a device and method for detecting the chlorophyll content of living plant leaves, which can be applicable to the detection of living plant leaves, reduce the influence on the accuracy of reflectance caused by the leaf inclination angle and leaf surface texture characteristics of plants, and improve the accuracy of chlorophyll content detection, has become an urgent problem to be solved. Summary of the Invention

[0006] Aiming at the defects in the prior art, the present invention provides a device and method for detecting the chlorophyll content of living plant leaves.

[0007] The present invention provides a device for detecting the chlorophyll content of living plant leaves, including: a spectral data acquisition module, a ranging module, an image acquisition module, and a main control processing module;

[0008] The spectral data acquisition module includes: a spectral sensor; the spectral sensor is used to acquire the spectral data of the to-be-detected leaf;

[0009] The ranging module includes: at least one ranging sensor; the ranging sensor is used to acquire the distance data between the ranging sensor and the to-be-detected leaf;

[0010] The image acquisition module includes: a camera; the camera is used to acquire the leaf surface image of the leaf to be measured.

[0011] The main control processing module is used to receive the data information of the leaf to be measured collected by the spectral data acquisition module, the ranging module and the image acquisition module, and determine the chlorophyll content of the leaf to be measured based on the data information of the leaf to be measured.

[0012] According to the plant living leaf chlorophyll content detection device provided by the present invention, it further includes: a laser indicator;

[0013] The laser indicator is arranged adjacent to the ranging sensor;

[0014] The laser indicator is used to calibrate the corresponding measurement position of the ranging sensor on the leaf to be measured.

[0015] According to the plant living leaf chlorophyll content detection device provided by the present invention, the ranging module includes: three ranging sensors;

[0016] The ranging sensors are arranged adjacent to the spectral sensor, and the three ranging sensors are not on a straight line.

[0017] According to the plant living leaf chlorophyll content detection device provided by the present invention, the three ranging sensors and the spectral sensor are in the same plane, and the three ranging sensors are distributed at right angles.

[0018] The present invention provides a plant living leaf chlorophyll content detection method implemented based on the above plant living leaf chlorophyll content detection device, including:

[0019] Based on the distance data, determine the leaf inclination angle of the leaf to be measured;

[0020] Based on the leaf surface image of the leaf to be measured, determine the leaf surface smoothness of the leaf to be measured;

[0021] Based on the spectral data of the leaf to be measured, the leaf inclination angle and the leaf surface smoothness of the leaf to be measured, determine the compensated reflected light amplitude of the leaf to be measured;

[0022] Based on the compensated reflected light amplitude of the leaf to be measured and the sunlight amplitude, determine the reflectivity of the leaf to be measured;

[0023] Based on the reflectivity of the leaf to be measured, determine the chlorophyll content of the leaf to be measured.

[0024] According to the plant living leaf chlorophyll content detection method provided by the present invention, the step of determining the leaf inclination angle of the leaf to be measured based on the distance data specifically includes:

[0025] Based on the distance data, determine the longitudinal leaf inclination angle and the lateral leaf inclination angle of the leaf to be measured;

[0026] Wherein, the longitudinal leaf inclination angle is the included angle between the direction of the leaf midrib and the ground horizontal direction; the lateral leaf inclination angle is the included angle between the direction perpendicular to the leaf midrib and the ground horizontal direction.

[0027] According to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, the determining of the smoothness of the leaf surface of the leaf to be measured based on the leaf surface image of the leaf to be measured specifically includes:

[0028] Based on the leaf surface image of the leaf to be measured, obtain the grayscale image of the leaf surface of the leaf to be measured;

[0029] Based on the grayscale image of the leaf surface, determine the standard deviation after normalizing the grayscale value of the leaf surface, and use the standard deviation after normalizing the grayscale value of the leaf surface as the smoothness of the leaf surface of the leaf to be measured.

[0030] According to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, the determining of the compensated reflected light amplitude of the leaf to be measured based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured specifically includes:

[0031] Based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured, calculate the compensated reflected light amplitude of the leaf to be measured according to the reflected light amplitude compensation correction formula.

[0032] According to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, the reflected light amplitude compensation correction formula is:

[0033]

[0034] Wherein, n is the light wavelength, with the unit of nm; y n is the compensated reflected light amplitude of the leaf to be measured when the light wavelength is n; θ is the longitudinal leaf inclination angle; α is the lateral leaf inclination angle; S is the leaf smoothness; D n / θ / α / S is the reflected light amplitude when the light wavelength is n; k n is the constant coefficient when the light wavelength is n.

[0035] According to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, after the step of determining the reflectance of the leaf to be measured based on the compensated reflected light amplitude of the leaf to be measured and the sunlight amplitude, it further includes:

[0036] Determine the data difference between the reflectance of the leaf to be measured at the currently preset light wavelength and the reflectance of the leaf to be measured at the previous preset light wavelength; wherein, the preset wavelength belongs to the near-infrared light range

[0037] If it is determined that the data difference is greater than a preset difference threshold, the sunlight amplitude is re-determined.

[0038] The plant living leaf chlorophyll content detection device and method provided by the present invention can be widely applied to the detection of plant living leaves. By determining the leaf inclination angle and leaf smoothness of the to-be-detected leaf, compensating and correcting the detected leaf reflection light amplitude, further calculating the leaf reflectance, and determining the chlorophyll content of the to-be-detected leaf according to the leaf reflectance, the influence caused by the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectance is effectively reduced, and the accuracy of chlorophyll content detection is improved. Description of the Drawings

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0040] Figure 1 It is one of the structural schematic diagrams of the plant living leaf chlorophyll content detection device provided by the present invention;

[0041] Figure 2 It is another structural schematic diagram of the plant living leaf chlorophyll content detection device provided by the present invention;

[0042] Figure 3 It is the flowchart of the plant living leaf chlorophyll content detection method provided by the present invention;

[0043] Figure 4 It is the schematic diagram of the method for detecting the longitudinal inclination angle of the leaf provided by the present invention;

[0044] Figure 5 It is the schematic diagram of the method for detecting the lateral inclination angle of the leaf provided by the present invention;

[0045] Figure 6 It is the schematic diagram of the light compensation experiment provided by the present invention;

[0046] Figure 7 It is the schematic flow diagram of the plant living leaf chlorophyll content detection method provided by the present invention;

[0047] Figure 8 It is the physical structure schematic diagram of the electronic device provided by the present invention.

[0048] Reference Signs:

[0049] 110: Spectral data acquisition module; 120: Distance measurement module;

[0050] 130: Image acquisition module; 140: Main control processing module;

[0051] 210: Spectral sensor; 220: Range sensor;

[0052] 230: Laser indicator; 240: Camera. Specific implementation mode

[0053] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0054] In the prior art, devices for detecting chlorophyll include Greenseeker (656nm and 774nm) and Greenseeker Handheld (660nm and 780nm) produced by Trimble Company, which can obtain the NDVI value of crops by acquiring the reflectance of red light and infrared light on crop leaves, so as to predict the chlorophyll content of crops; the MSR5 / 87 / 16R series spectrometers produced by CropScan Company can obtain the reflectance of several bands between 450-1750nm on crop leaves, so as to calculate different vegetation indices or substitute them into the model to invert the chlorophyll content; the Crop Circle series developed by Holland Company can obtain the spectra of several bands between 450-900nm of crops to predict the chlorophyll content.

[0055] The above-mentioned instruments can quickly and nondestructively obtain the reflectance of characteristic bands of crops to invert the chlorophyll content. However, there are still the following problems:

[0056] (1) When the crop leaves reflect, the optical probe is usually perpendicular to the leaves to obtain the reflected light radiation intensity signal. However, for crops with large single leaf areas such as corn and bananas, due to the growth and extension of their leaves, they cannot be in a horizontal form and are inclined in three-dimensional space. The reflected light has scattered directionality and diffuse reflection heterogeneity, resulting in large measurement errors of the usually single-point reflected light;

[0057] (2) Different crop leaves have different smoothness due to the presence of wax or differences in structure. When the surface of the leaf is smoother, specular reflection occurs when it is tilted, resulting in a decrease in the amplitude of the reflected light. The rougher the leaf surface, the more likely it is to have diffuse reflection, and most of the reflected light is retained. Due to the presence of surface wax and differences in tissue structure in living leaves, the surface affects the radiation intensity of single-point reflected light, resulting in low accuracy in chlorophyll spectroscopy detection; thus limiting the application of crop chlorophyll content detection devices based on reflection spectra in the field.

[0058] To address the above two problems, the present invention provides a device and method for detecting the chlorophyll content of living plant leaves. By determining the leaf inclination angle and leaf smoothness of the leaf to be measured, the amplitude of the detected leaf reflected light is compensated and corrected, effectively reducing the influence of plant leaf inclination angle and leaf surface texture characteristics on the accuracy of reflectivity, and improving the accuracy of chlorophyll content detection.

[0059] Figure 1 One of the structural schematic diagrams of the device for detecting the chlorophyll content of living plant leaves provided by the present invention is as Figure 1 shown. The present invention provides a device for detecting the chlorophyll content of living plant leaves, including:

[0060] a spectral data acquisition module, a ranging module, an image acquisition module, and a main control processing module;

[0061] The spectral data acquisition module includes: a spectral sensor; the spectral sensor is used to acquire spectral data of the leaf to be measured;

[0062] The ranging module includes: at least one ranging sensor; the ranging sensor is used to acquire distance data between the ranging sensor and the leaf to be measured;

[0063] The image acquisition module includes: a camera; the camera is used to acquire a leaf surface image of the leaf to be measured;

[0064] The main control processing module is used to receive the data information of the leaf to be measured acquired by the spectral data acquisition module, the ranging module, and the image acquisition module, and determine the chlorophyll content of the leaf to be measured based on the data information of the leaf to be measured.

[0065] Specifically, the device for detecting the chlorophyll content of living plant leaves provided by the present invention includes: a spectral data acquisition module 110, a ranging module 120, an image acquisition module 130, and a main control processing module 140;

[0066] Figure 2 Another structural schematic diagram of the device for detecting the chlorophyll content of living plant leaves provided by the present invention is as Figure 2As shown in the figure, the spectral data acquisition module 110 includes a spectral sensor 210, and the spectral sensor 210 is used to acquire the spectral data of the leaf to be measured.

[0067] The ranging module 120 includes at least one ranging sensor 220. The ranging sensor 220 is arranged close to the spectral sensor 210. The ranging sensor 220 is used to acquire the distance data between the sensor and the leaf to be measured. Based on the position of different measurement points on the leaf to be measured and the distance data between the sensor and the leaf to be measured, the leaf inclination angle near the spectral sensor 210 can be determined.

[0068] It can be understood that multiple points on the leaf surface need to be measured to determine the leaf surface inclination angle. During the measurement, if only one ranging sensor is designed, multiple measurements need to be repeated. If multiple sensors are set, the measurement result can be determined at one time. The specific measurement method is adapted to the design of the device, and the specific steps are not limited in this invention.

[0069] The image acquisition module 130 includes a camera 240, and the camera 240 is used to acquire the leaf surface image of the leaf to be measured. The smoothness of the leaf surface can be analyzed using this leaf surface image.

[0070] The main control processing module 140 is used to receive the data information of the leaf to be measured collected by the spectral data acquisition module 110, the ranging module 120, and the image acquisition module 130. Based on the data information of the leaf to be measured, the leaf inclination angle of the leaf to be measured is determined through the distance data, the smoothness of the leaf surface is determined through the leaf surface image, and further, through the leaf inclination angle and the smoothness of the leaf surface, the collected spectral data (i.e., the reflected light amplitude) is corrected, and further, the chlorophyll content of the leaf to be measured is calculated.

[0071] Furthermore, it can be understood that during the specific hardware design, the chlorophyll content detection device for living plant leaves can also be provided with a power supply module, a wireless transmission module, a display terminal, and a storage module.

[0072] The display terminal is a smart phone, a tablet, a PC, etc. By turning on the hotspot to connect to the main control core processor (through the wireless transmission module), a good human-computer interaction mode is provided. The data results processed by the main control processing module can be displayed in real time through a web page, an APP, or a small program, and the historical data can be viewed. There is no external display screen. Through the portable smart phone and tablet, the real-time viewing of data during the detection of chlorophyll in the field can be realized. Through the PC, the remote monitoring of data during the detection of chlorophyll in the field can be realized.

[0073] The power supply module uses a 14500 lithium battery in conjunction with the SW6106 chip to regulate the voltage to 5V for powering the entire system. The battery is replaceable and rechargeable, which can improve the portability and long-term working performance of the instrument. The DW01 chip and 8205 chip are used to protect the lithium battery to prevent overcharging and over-discharging. Since near-earth remote sensing field tests require single-point collection, the design of the power supply module can meet the requirements of long-term stable operation in the field.

[0074] The storage module selects a 16G memory card to store the processor system, software programs, and data.

[0075] The main control processing module can use the Raspberry Pi Zero W. It uses a processor with an architecture of 1GHz ARM11 core, and its size is 65mm x 30mm x 5mm. The device is powered by 5V and provides 3.3V voltage to power the sensors through the GPIO ports, and communicates with the sensors via I 2 C. It stores programs and data through the SD card and is also equipped with an 802.11b / g / n WiFi wireless network card for connecting to the display terminal, enabling rapid data processing and intuitive result display.

[0076] The spectral data acquisition module uses the AS265X compact 18-channel chipset launched by ams AG, which consists of 3 highly integrated 6-channel sensor devices (AS72651, AS72652, AS71653). (It has the advantages of low cost, miniaturization, high wavelength accuracy, and low power consumption, and is an inexpensive alternative for on-site measurement.) The chipset uses a compact grid array package with an integrated aperture, integrates intelligent help for calibration of digital output, and is managed by the host microprocessor via an optional I2C or UART interface. The 18 channels of the chipset in the range of 400 - 960nm all have a full width at half maximum of 20nm, and the wavelength centers are 410, 435, 460, 485, 510, 535, 560, 585, 610, 645, 680, 705, 730, 760, 810, 860, 900, and 940nm respectively. This sensor has a large number of bands, and the range is distributed from 400 to 950nm, which can cover the characteristic spectral range of chlorophyll. Appropriate vegetation indices can be selected or local models can be established to improve the applicability of the instrument in different environments.

[0077] The ranging module uses the HC-SR04 ultrasonic ranging module, which can provide non-contact distance sensing function from 2 cm to 400 cm. The ranging accuracy can reach up to 3 mm. The module automatically sends 8 square waves of 40 kHz and automatically detects whether there is a signal return. If there is a signal return, a high level is output through the IO port ECHO. The duration of the high level is the time for the ultrasonic wave to travel from transmission to return. Among them, the measured distance = (high level time * speed of sound (340 m / s)) / 2

[0078] The image data acquisition module selects the RPi Camera (B), which uses the OV5647 photosensitive chip, has 5 million pixels, and the field of view angle is 60.6°.

[0079] It should be noted that the above hardware design is only used as a specific example to illustrate the plant live leaf chlorophyll content detection device provided by the present invention. In the actual application process, for the specific structure and appearance of the plant live leaf chlorophyll content detection device in the present invention, the installation positions of each module, and the specific selection of the hardware in each module. For the software settings of the system, it matches the hardware design (for example, the control software is designed according to the data acquisition, processing, storage and viewing functions required in the field, and the software is written in the python language). The specific settings of the hardware design and software design can be adjusted according to actual needs, and this embodiment does not limit this.

[0080] The plant live leaf chlorophyll content detection device provided by the present invention can be widely applied to the detection of plant live leaves. By determining the leaf inclination angle and leaf smoothness of the leaf to be measured, compensating and correcting the detected leaf reflection light amplitude value, further calculating the leaf reflectance, and determining the chlorophyll content of the leaf to be measured according to the leaf reflectance, it effectively reduces the influence of the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectance, and improves the accuracy of chlorophyll content detection.

[0081] Optionally, according to the plant live leaf chlorophyll content detection device provided by the present invention, it further includes: a laser indicator;

[0082] The laser indicator is arranged adjacent to the ranging sensor;

[0083] The laser indicator is used to calibrate the corresponding measurement position of the ranging sensor on the leaf to be measured.

[0084] Specifically, as Figure 2 shown, the plant live leaf chlorophyll content detection device further includes: a laser indicator 230, and the laser indicator 230 is arranged adjacent to the ranging sensor 220.

[0085] The laser indicator 230 can emit solid laser. When performing ranging detection, it is used to calibrate the corresponding measurement position of the ranging sensor 220 on the to-be-detected leaf, enabling the human eye to accurately observe the corresponding measurement position measured by the ranging sensor 220 and facilitating the selection of measurement points.

[0086] It should be noted that the ranging sensor can be adaptively selected and set as an ultrasonic ranging sensor, a laser ranging sensor, an infrared ranging sensor, etc. It can be understood that in addition to setting a laser indicator alone, a ranging sensor integrated with a calibration function can also be selected, and the present invention does not limit this.

[0087] The plant living leaf chlorophyll content detection device provided by the present invention can be widely applied to the detection of plant living leaves. The setting of the laser indicator facilitates observing the measurement position of the ranging sensor, improving the accuracy during detection. By determining the leaf inclination angle and leaf smoothness of the to-be-detected leaf, compensating and correcting the detected leaf reflected light amplitude value, further calculating the leaf reflectance, and determining the chlorophyll content of the to-be-detected leaf according to the leaf reflectance, it effectively reduces the influence of plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectance, improving the accuracy of chlorophyll content detection.

[0088] Optionally, according to the plant living leaf chlorophyll content detection device provided by the present invention, the ranging module includes: three ranging sensors;

[0089] The ranging sensors are arranged adjacent to the spectral sensor, and the three ranging sensors are not on a straight line.

[0090] Specifically, as Figure 2 shown, the ranging module 120 in the plant living leaf chlorophyll content detection device includes: three ranging sensors 220. The ranging sensors 220 are arranged adjacent to the spectral sensor 210 on the same plane, and the three ranging sensors 220 are not on a straight line, and the detection directions are all vertically downward.

[0091] It should be noted that the ranging sensors are distributed in a triangle on the plane. The specific triangle shape (such as: isosceles triangle, equilateral triangle, right triangle, etc.) and the distance between the ranging sensors can be set according to actual needs. When calculating the leaf inclination angle, the specific calculation formula is adapted to the distribution and distance of the ranging sensors. In actual applications, all can be adjusted according to the actual situation, and the present invention does not limit this.

[0092] The plant live leaf chlorophyll content detection device provided by the present invention can be widely applied to the detection of plant live leaves. By setting three ranging sensors, it can accurately reflect the inclination degree of the leaf in the three-dimensional space, further determine the leaf inclination angle and leaf smoothness of the to-be-detected leaf, compensate and correct the detected leaf reflected light amplitude value, further calculate the leaf reflectivity, and determine the chlorophyll content of the to-be-detected leaf according to the leaf reflectivity, effectively reducing the influence caused by the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectivity, and improving the accuracy of chlorophyll content detection.

[0093] Optionally, for the plant live leaf chlorophyll content detection device provided by the present invention, the three ranging sensors and the spectral sensor are located in the same plane, and the three ranging sensors are distributed at right angles.

[0094] Specifically, for the convenience of calculation, the three ranging sensors 220 are arranged in the same plane as the spectral sensor 210, and the three ranging sensors 220 are distributed at right angles.

[0095] As Figure 2 shown, the three ranging sensors 220 are distributed at right angles. It should be noted that the distance between the ranging sensors 220 can be set according to actual needs. For example, the distance between the left and right ranging sensors 220 can be set to 10 cm, and the distance between the front and rear ranging sensors 220 can be set to 5 cm.

[0096] The plant live leaf chlorophyll content detection device provided by the present invention can be widely applied to the detection of plant live leaves. By setting three ranging sensors 220 distributed in a right triangle, it can accurately reflect the inclination degree of the leaf in the three-dimensional space, further determine the leaf inclination angle and leaf smoothness of the to-be-detected leaf, compensate and correct the detected leaf reflected light amplitude value, further calculate the leaf reflectivity, and determine the chlorophyll content of the to-be-detected leaf according to the leaf reflectivity, effectively reducing the influence caused by the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectivity, and improving the accuracy of chlorophyll content detection.

[0097] Figure 3 For the flowchart of the plant live leaf chlorophyll content detection method provided by the present invention, as Figure 3 shown, the present invention provides a plant live leaf chlorophyll content detection method implemented based on the above plant live leaf chlorophyll content detection device, including:

[0098] Step S1, based on the distance data, determine the leaf inclination angle of the to-be-detected leaf;

[0099] Step S2, based on the leaf surface image of the to-be-detected leaf, determine the leaf surface smoothness of the to-be-detected leaf;

[0100] Step S3: Based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured, determine the amplitude of the reflected light of the leaf to be measured after compensation;

[0101] Step S4: Based on the amplitude of the reflected light of the leaf to be measured after compensation and the amplitude of sunlight, determine the reflectivity of the leaf to be measured;

[0102] Step S5: Based on the reflectivity of the leaf to be measured, determine the chlorophyll content of the leaf to be measured.

[0103] Specifically, when detecting the leaf to be measured, place the above-mentioned chlorophyll content detection device for living plant leaves horizontally above the leaf, and collect the data information of the leaf to be measured through the spectral data acquisition module 110, the ranging module 120, and the image acquisition module 130. The data information of the leaf to be measured includes: spectral data, distance data, and leaf surface image.

[0104] In step S1, based on the collected distance data, calculate and determine the leaf inclination angle of the leaf to be measured according to the distances between different positions on the leaf surface and the ranging sensor 220 and the distances between the acquisition points.

[0105] In step S2, based on the leaf surface image of the leaf to be measured, analyze the texture of the leaf surface to determine the smoothness of the leaf surface of the leaf to be measured.

[0106] It should be noted that there is no clear index to evaluate the smoothness of the leaf. In this solution, based on the characteristics of the image, a value that can reflect the texture characteristics of the image can be selected, such as: indicators such as the standard deviation of the image gray value and the degree of pixel value difference to characterize the smoothness of the leaf surface. The specific characterization method can be determined according to the actual situation, and the present invention does not limit this.

[0107] In step S3, based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured, correct the collected spectral data (i.e., the amplitude of the reflected light) through the leaf inclination angle and the smoothness of the leaf surface to determine the amplitude of the reflected light of the leaf to be measured after compensation.

[0108] It can be understood that when correcting the amplitude of the reflected light, data experimental data can be used to fit the relationship between the amplitude of the reflected light, the leaf inclination angle, and the smoothness of the leaf surface, determine the fitting formula, and correct the amplitude of the reflected light of the leaf according to the formula. In addition, a neural network model can also be constructed, and the leaf emission light correction model is obtained through a large amount of data training, and the amplitude of the reflected light of the leaf to be measured after compensation is determined through the neural network model. The specific correction method can be selected according to actual needs, and the present invention does not limit this.

[0109] In step S4, based on the amplitude of the reflected light of the leaf to be measured after compensation and the amplitude of sunlight, calculate the reflectivity of the leaf to be measured.

[0110] Denote the sunlight amplitude as S n , and denote the amplitude of the reflected light of the leaf to be measured after compensation as y n , where n is the light wavelength, with the unit of nm. The reflectivity of the leaf to be measured The reflectivity of the leaf to be measured at different wavelength bands can be determined accordingly.

[0111] In step S5, based on the reflectivity of the leaf to be measured, determine the chlorophyll content of the leaf to be measured.

[0112] It should be noted that based on the reflectivity of the leaf to be measured, the vegetation index NDVI can be constructed or a suitable model can be constructed to determine the chlorophyll content of the leaf to be measured. The specific method can be selected according to actual needs, and the present invention does not make any limitation in this regard.

[0113] Taking the construction of the vegetation index NDVI for chlorophyll content prediction as an example, when constructing the vegetation index, according to the formula (R nir is the reflectivity in the near-infrared band, and the 860nm band is selected here; R red is the red light band, and the 680nm band is selected here), after obtaining the NDVI value, the chlorophyll content C = γ * NDVI, where γ is a coefficient.

[0114] It can be understood that the above method for predicting chlorophyll content by constructing the vegetation index NDVI is only a specific example to explain how to predict chlorophyll content. In the actual application of the present invention, the method used and the data applied can be adjusted according to the actual situation, and the present invention does not make any limitation in this regard.

[0115] The method for detecting the chlorophyll content of living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves. By determining the leaf inclination angle and leaf smoothness of the leaf to be measured, compensating and correcting the amplitude of the detected leaf reflected light, further calculating the leaf reflectivity, and determining the chlorophyll content of the leaf to be measured according to the leaf reflectivity, the influence caused by the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectivity can be effectively reduced, and the accuracy of chlorophyll content detection can be improved.

[0116] Optionally, according to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, determining the leaf inclination angle of the leaf to be measured based on the distance data specifically includes:[[]]

[0117] Based on the distance data, determine the longitudinal leaf inclination angle and the transverse leaf inclination angle of the leaf to be measured;

[0118] Among them, the longitudinal inclination angle of the leaf is the angle between the direction of the midrib of the leaf and the horizontal direction of the ground; the transverse inclination angle of the leaf is the angle between the direction perpendicular to the midrib of the leaf and the horizontal direction of the ground.

[0119] Specifically, based on the distance data, determining the leaf inclination angle of the leaf to be measured specifically includes:

[0120] Based on the distance data, determining the longitudinal inclination angle and the transverse inclination angle of the leaf to be measured.

[0121] Among them, the longitudinal inclination angle of the leaf is the angle between the direction of the midrib of the leaf and the horizontal direction of the ground; the transverse inclination angle of the leaf is the angle between the direction perpendicular to the midrib of the leaf and the horizontal direction of the ground.

[0122] Such as Figure 2 As shown, taking the plant in-vivo leaf chlorophyll content detection device with three ranging sensors 220 distributed in a right triangle as an example, the method for calculating the leaf inclination angle is described in detail:

[0123] Figure 4 Schematic diagram of the method for detecting the longitudinal inclination angle of the leaf provided by the present invention. As Figure 4 As shown, when the detection device is horizontally placed above the leaf, the laser probe emits red light to mark the position of the leaf. After determining the appropriate acquisition position, the left and right ranging sensors 220 perform distance acquisition, and the obtained distance data are h1 and h2 respectively. L is the distance between the left and right ranging sensors 220.

[0124] At this time, the magnitude of the longitudinal inclination angle θ of the leaf is related to the difference between L and the values obtained by the two ranging sensors 220. That is:

[0125]

[0126]

[0127] Figure 5 Schematic diagram of the method for detecting the transverse inclination angle of the leaf provided by the present invention. As Figure 5 As shown, when the detection device is horizontally placed above the leaf, the laser probe emits red light to mark the position of the leaf. After determining the appropriate acquisition position, the front and rear ranging modules 120 perform distance acquisition, and the obtained distance data are h2 and h3 respectively. L' is the distance between the two ranging modules 120.

[0128] At this time, the magnitude of the transverse inclination angle α of the leaf is related to the difference between L' and the values obtained by the two ranging sensors 220. That is:

[0129]

[0130]

[0131] The leaf inclination angle of each leaf of the crop is different and cannot be fixed. To solve the problem of large measurement errors in reflected light radiation caused by the leaf inclination angle and phototropism of the living leaves of the crop plant, it is necessary to measure the inclination angle each time the reflected light amplitude is obtained and calculate the inclined plane of the leaf in three-dimensional space.

[0132] When detecting with a monitoring device provided with three distance measuring sensors 220, the three measured points can form a plane, and the three measured values can be used to calculate the longitudinal inclination angle θ of the leaf and the transverse inclination angle α of the leaf (the inclination angles in the front-back and left-right directions).

[0133] It can be understood that since it is necessary to determine the inclined plane in three-dimensional space, designing three distance measuring sensors 220 can obtain the required data in one detection. If the number of distance measuring sensors 220 is less than three, multiple measurements are required. If the measurement position points are not perpendicular to each other, the calculation formula needs to be adjusted adaptively, and the present invention does not limit this.

[0134] The method for detecting the chlorophyll content of living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves, calculate and determine the longitudinal inclination angle θ of the leaf and the transverse inclination angle α of the leaf, which are used to represent the inclined plane of the leaf in three-dimensional space. By determining the leaf inclination angle and leaf smoothness of the to-be-detected leaf, compensating and correcting the detected reflected light amplitude of the leaf, effectively improving the problem of weakening of the reflected light radiation intensity caused by the leaf inclination angle, further calculating the leaf reflectivity, making the reflectivity measurement more accurate, determining the chlorophyll content of the to-be-detected leaf according to the leaf reflectivity, effectively reducing the influence of the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectivity, and improving the accuracy of chlorophyll content detection.

[0135] Optionally, according to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, determining the smoothness of the leaf surface of the to-be-detected leaf based on the leaf surface image of the to-be-detected leaf specifically includes:

[0136] Based on the leaf of the to-be-detected leaf, obtain the grayscale image of the leaf surface of the to-be-detected leaf;

[0137] Based on the grayscale image of the leaf surface, determine the standard deviation after normalizing the grayscale value of the leaf surface, and use the standard deviation after normalizing the grayscale value of the leaf surface as the smoothness of the leaf surface of the to-be-detected leaf.

[0138] Specifically, determining the smoothness of the leaf surface of the to-be-detected leaf based on the leaf surface image of the to-be-detected leaf specifically includes:

[0139] Based on the leaf surface image of the to-be-detected leaf, obtain the grayscale image of the leaf surface of the to-be-detected leaf.

[0140] It is understandable that due to the shooting height, the captured image may include the background image in addition to the leaves. After obtaining the RGB image of the leaf surface, threshold segmentation can be used to retain only the leaf surface part, and then grayscale processing can be performed to obtain the grayscale image of the leaf surface of the leaf to be measured.

[0141] Based on the grayscale image of the leaf surface, the grayscale values are normalized, and the standard deviation of the normalized grayscale values of the leaf surface part is calculated. The standard deviation of the normalized grayscale values of the leaf surface represents the smoothness S of the leaf surface of the leaf to be measured.

[0142] The method for detecting the chlorophyll content of living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves. By obtaining the leaf inclination angle of the crop to compensate the reflected light amplitude, an image acquisition module is used to collect the RGB image of the leaf surface for smoothness analysis to correct the reflected light amplitude, so as to obtain a more accurate light amplitude, thereby improving the accuracy of reflectance measurement. Further calculate the leaf reflectance, and determine the chlorophyll content of the leaf to be measured according to the leaf reflectance, effectively reducing the influence of the plant leaf inclination angle and the leaf surface texture characteristics on the accuracy of the reflectance, and improving the accuracy of chlorophyll content detection.

[0143] Optionally, according to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, determining the compensated reflected light amplitude of the leaf to be measured based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured specifically includes:

[0144] Based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured, according to the reflected light amplitude compensation and correction formula, calculate the compensated reflected light amplitude of the leaf to be measured.

[0145] Specifically, determining the compensated reflected light amplitude of the leaf to be measured based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured specifically includes:

[0146] Before correcting the reflected light amplitude of the leaf to be measured, based on a large amount of data obtained through experiments, fit and establish a reflected light amplitude compensation and correction formula.

[0147] Based on the spectral data of the leaf to be measured, the leaf inclination angle, and the smoothness of the leaf surface of the leaf to be measured, according to the reflected light amplitude compensation and correction formula, compensate and correct the reflected light amplitude, and calculate the compensated reflected light amplitude of the leaf to be measured.

[0148] The chlorophyll content detection method for living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves. The leaf inclination angle is calculated to compensate for the reflected light amplitude, and a camera 240 is used to analyze the leaf surface texture, so as to correct the reflectivity and invert the chlorophyll content, effectively reducing the influence of plant leaf inclination angle and leaf surface texture characteristics on the accuracy of reflectivity, improving the accuracy of chlorophyll content detection, and realizing rapid, non-destructive and accurate detection of crop chlorophyll content.

[0149] Optionally, according to the chlorophyll content detection method for living plant leaves provided by the present invention, the reflected light amplitude compensation and correction formula is:

[0150]

[0151] wherein, n is the light wavelength, with the unit of nm; y n is the reflected light amplitude of the to-be-detected leaf after compensation at the light wavelength of n; θ is the longitudinal inclination angle of the leaf; α is the transverse inclination angle of the leaf; S is the leaf smoothness; D n / θ / α / S is the reflected light amplitude at the light wavelength of n; k n is the constant coefficient at the light wavelength of n.

[0152] Specifically, the weakening of the reflected light radiation intensity caused by the leaf inclination angle needs to be compensated. For the method of accurately detecting the reflected light radiation intensity at different angles, refer to the tangent value of the current angle and the reflection amplitude value obtained at the vertical angle for fitting to obtain the compensation formula, and apply the compensation formula to compensate the reflected light amplitude value to obtain a more accurate reflectivity, so as to be able to invert a more accurate chlorophyll content.

[0153] Figure 6 is the schematic diagram of the light compensation experiment provided by the present invention. As Figure 6 shown, after obtaining the tangent value of the leaf inclination angle, it is necessary to compensate the detected reflected light amplitude of the leaf surface (taking the detection of the reflected light radiation values of crop leaves in the detection bands of 410, 435, 460, 485, 510, 535, 560, 585, 610, 645, 680, 705, 730, 760, 810, 860, 900 and 940 nm as an example). The method for establishing the compensation formula is as follows:

[0154] (1) During the experiment, keep the ambient light unchanged and keep the same distance between the sensor and the leaf surface;

[0155] (2) When the instrument forms a 90° angle with the leaf surface, obtain the reflected light amplitudes D 410 / 90 , D 435 / 90 , D 460 / 90 , D 485 / 90 , D 510 / 90 , D 535 / 90 , D 560 / 90 , D585 / 90 , D 610 / 90 , D 645 / 90 , D 680 / 90 , D 705 / 90 , D 730 / 90 , D 760 / 90 , D 810 / 90 , D 860 / 90 , D 900 / 90 , D 940 / 90 ;

[0156] (3) Next, the included angle measured each time is reduced by 5° until it reaches 30°, and a total of 13 groups of data are obtained;

[0157] (4) Repeat the experiment 3 times and average the data of the three times;

[0158] (5) Fit the data at different angles for each band with the tangent value of the angle to establish a fitting equation:

[0159] y n = D n / θ * [1 + k n * tan(π / 2 - θ)]

[0160] (6) When compensating for the reflected light radiation value, it is necessary to consider the influence of the tilt angles in the front-back and left-right (longitudinal and transverse) directions. Therefore, the reflected light amplitude compensation formula is:

[0161]

[0162] Among them, n is the wavelength of the light, with the unit of nm; y n is the compensated reflected light amplitude of the leaf to be measured when the light wavelength is n; θ is the longitudinal tilt angle of the leaf; α is the transverse tilt angle of the leaf; D n / θ is the reflected light amplitude when the light wavelength is n and the longitudinal tilt angle of the leaf is θ; D n / θ / α is the reflected light amplitude when the light wavelength is n, the longitudinal tilt angle of the leaf is θ, and the transverse tilt angle of the leaf is α; k n is the constant coefficient when the light wavelength is n.

[0163] k1…k n are 0.47, 0.49, 0.46, 0.45, 0.45, 0.47, 0.48, 0.46, 0.45, 0.49, 0.5, 0.55, 0.53, 0.5, 0.52, 0.55, 0.53, 0.51 respectively.

[0164] To solve the problem that the reflected light amplitudes of different crop leaves are different when tilted due to different surface texture structures. After obtaining the smoothness, the difference in the reflected light amplitude intensity caused by different smoothness needs to be corrected. The method for establishing the correction formula is as follows:

[0165] (1) Keep the ambient light constant during the experiment and keep the sensor at the same distance from the leaf surface;

[0166] (2) Select leaves with different smoothness and conduct experiments according to the experimental method in Figure 6 .

[0167] (3) Conduct data fitting and establish a fitting equation:

[0168]

[0169] Therefore, the final compensation and correction formula for the reflected light amplitude is as follows:

[0170]

[0171] where S is the leaf smoothness; D n / θ / α / S is the reflected light amplitude when the light wavelength is n (at this time, the longitudinal tilt angle of the leaf is θ, the transverse tilt angle of the leaf is α, and the leaf smoothness is S).

[0172] It should be noted that the method for establishing the above fitting equation is only a specific example to illustrate how the present invention compensates the reflected light amplitude of the leaf through the leaf tilt angle. When the present invention is actually applied, the process of determining the fitting formula can be adjusted according to the actual situation, and the present invention does not limit this.

[0173] The method for detecting the chlorophyll content of living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves, calculate the leaf tilt angle to make up for the reflected light amplitude, analyze the leaf surface texture by using the camera 240, so as to correct the reflectance to invert the chlorophyll content, effectively reduce the influence of the plant leaf tilt angle and the leaf surface texture characteristics on the accuracy of the reflectance, improve the accuracy of chlorophyll content detection, and realize rapid, non-destructive and accurate detection of the chlorophyll content of crops.

[0174] Optionally, according to the method for detecting the chlorophyll content of living plant leaves provided by the present invention, after the step of determining the reflectance of the to-be-detected leaf based on the compensated reflected light amplitude of the to-be-detected leaf and the sunlight amplitude, the following steps are further included:

[0175] Determine the data difference between the reflectance of the to-be-detected leaf at the current preset light wavelength and the reflectance of the to-be-detected leaf at the previous preset light wavelength; wherein, the preset wavelength belongs to the near-infrared light range

[0176] If it is determined that the data difference is greater than the preset difference threshold, re-determine the sunlight amplitude.

[0177] Specifically, when applying the present invention to continuously detect the chlorophyll content of leaves, it is not necessary to calibrate the white board before each acquisition of the data of the leaves to be measured. Only the white board needs to be calibrated when collecting data for the first time, and the amplitude of the reflected light of the white board (the amplitude of sunlight) is collected. When collecting data next time, it is only necessary to determine whether the difference value is too large and the sunlight amplitude needs to be updated. If it is determined that there is no need to update, the data used last time can be continued to be used.

[0178] Figure 7 It is a schematic flow chart of the method for detecting the chlorophyll content of living plant leaves provided by the present invention. As Figure 7 shown, when using the device for detecting the chlorophyll content of living plant leaves provided by the present invention to detect chlorophyll, to ensure the accuracy of the reflectance acquisition, the distances from the acquisition instrument to three points on the leaf are measured, and the difference is calculated to obtain the longitudinal and transverse tilt angles of the leaf; the image information of the crop leaf surface is collected, the smoothness analysis is carried out, after the amplitude of the reflected light of the crop leaf is collected, the amplitude of the reflected light is compensated and corrected, and the reflectance is calculated according to the compensated amplitude of the reflected light to determine the reflectance.

[0179] If it is determined the data difference between the reflectance of the leaves to be measured with the current preset light wavelength and the reflectance of the leaves to be measured with the previous preset light wavelength, and if it is determined that the data difference is greater than the preset difference threshold (for example: 10%), then the sunlight amplitude is re-determined. Among them, the preset wavelength belongs to the near-infrared light range. For example, the 940nm band is selected.

[0180] When the difference between the 940nm band and the previous data is greater than 10%, it is prompted to re-calibrate the white board; when the data difference is less than 10%, the reflectance is calculated to invert the chlorophyll content.

[0181] It should be noted that in the actual application process of the present invention, the preset difference threshold and the preset wavelength can be adjusted according to the actual situation, and the present invention does not limit this.

[0182] It can be understood that since the preset wavelength belongs to the near-infrared light range and plants hardly absorb near-infrared light, this value changes little under the same sunlight intensity. Selecting this band to judge the change of the sunlight amplitude during the white board calibration can accurately determine whether the change of the sunlight amplitude is too large and whether re-calibration is needed. Compared with the prior art, the white board is re-calibrated with the full-band light intensity data each time of detection.

[0183] The method for detecting the chlorophyll content of living plant leaves provided by the present invention can be widely applied to the detection of living plant leaves. By determining the leaf inclination angle and leaf smoothness of the leaf to be measured, compensating and correcting the detected leaf reflection light amplitude value, further calculating the leaf reflectance, and determining the chlorophyll content of the leaf to be measured according to the leaf reflectance, the influence caused by the plant leaf inclination angle and leaf surface texture characteristics on the accuracy of the reflectance is effectively reduced, and the accuracy of chlorophyll content detection is improved. At the same time, using the data difference of the reflectance data of the leaf to be measured at a preset wavelength in the near-infrared light range as the standard for whether to recalibrate the whiteboard can effectively reduce the workload of detection and improve the detection efficiency without affecting the detection accuracy.

[0184] Figure 8 It is a schematic physical structure diagram of the electronic device provided by the present invention, as Figure 8 shown. The electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840. Among them, the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call the logical instructions in the memory 830 to execute the above-mentioned method for detecting the chlorophyll content of living plant leaves, including: determining the leaf inclination angle of the leaf to be measured based on the distance data; determining the leaf surface smoothness of the leaf to be measured based on the leaf surface image of the leaf to be measured; determining the compensated reflected light amplitude value of the leaf to be measured based on the spectral data of the leaf to be measured, the leaf inclination angle, and the leaf surface smoothness of the leaf to be measured; determining the leaf reflectance of the leaf to be measured based on the compensated reflected light amplitude value of the leaf to be measured and the sunlight amplitude value; and determining the chlorophyll content of the leaf to be measured based on the leaf reflectance of the leaf to be measured.

[0185] In addition, when the logical instructions in the above-mentioned memory 830 are implemented in the form of a software functional unit and sold or used as an independent product, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk, or an optical disc that can store program codes.

[0186] On the other hand, an embodiment of the present invention further provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the plant living leaf chlorophyll content detection method provided by each of the above method embodiments. The method includes: determining the leaf inclination angle of the to-be-detected leaf based on the distance data; determining the leaf surface smoothness of the to-be-detected leaf based on the leaf surface image of the to-be-detected leaf; determining the compensated reflected light amplitude of the to-be-detected leaf based on the spectral data of the to-be-detected leaf, the leaf inclination angle, and the leaf surface smoothness of the to-be-detected leaf; determining the reflectivity of the to-be-detected leaf based on the compensated reflected light amplitude of the to-be-detected leaf and the sunlight amplitude; and determining the chlorophyll content of the to-be-detected leaf based on the reflectivity of the to-be-detected leaf.

[0187] In another aspect, an embodiment of the present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it is configured to execute the plant living leaf chlorophyll content detection method provided by each of the above embodiments. The method includes: determining the leaf inclination angle of the to-be-detected leaf based on the distance data; determining the leaf surface smoothness of the to-be-detected leaf based on the leaf surface image of the to-be-detected leaf; determining the compensated reflected light amplitude of the to-be-detected leaf based on the spectral data of the to-be-detected leaf, the leaf inclination angle, and the leaf surface smoothness of the to-be-detected leaf; determining the reflectivity of the to-be-detected leaf based on the compensated reflected light amplitude of the to-be-detected leaf and the sunlight amplitude; and determining the chlorophyll content of the to-be-detected leaf based on the reflectivity of the to-be-detected leaf.

[0188] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0189] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0190] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A detection device for the chlorophyll content of living plant leaves, characterized in that, Including: A spectral data acquisition module, a ranging module, an image acquisition module, and a main control processing module; The spectral data acquisition module includes: a spectral sensor; the spectral sensor is used to acquire spectral data of the to-be-detected leaf; The ranging module includes: at least one ranging sensor; the ranging sensor is used to acquire distance data between it and the to-be-detected leaf; The image acquisition module includes: a camera; the camera is used to acquire the leaf surface image of the to-be-detected leaf; The main control processing module is used to receive the data information of the to-be-detected leaf acquired by the spectral data acquisition module, the ranging module, and the image acquisition module, and determine the chlorophyll content of the to-be-detected leaf based on the data information of the to-be-detected leaf; wherein, the chlorophyll content of the to-be-detected leaf is determined by the following method: Based on the distance data, determine the leaf inclination angle of the to-be-detected leaf; Based on the leaf surface image of the to-be-detected leaf, determine the leaf surface smoothness of the to-be-detected leaf; Based on the spectral data of the to-be-detected leaf, the leaf inclination angle, and the leaf surface smoothness of the to-be-detected leaf, according to the reflected light amplitude compensation and correction formula, determine the compensated reflected light amplitude of the to-be-detected leaf; the reflected light amplitude compensation and correction formula is: where n is the light wavelength, with the unit of nm; y n is the amplitude of the reflected light of the leaf to be measured after compensation when the light wavelength is n; θ is the longitudinal inclination angle of the leaf; α is the transverse inclination angle of the leaf; S is the smoothness of the leaf; D n / θ / α / S is the amplitude of the reflected light when the light wavelength is n; k n is the constant coefficient when the light wavelength is n; Based on the compensated reflected light amplitude of the to-be-detected leaf and the sunlight amplitude, determine the reflectivity of the to-be-detected leaf; Based on the reflectivity of the to-be-detected leaf, determine the chlorophyll content of the to-be-detected leaf.

2. The plant live leaf chlorophyll content detection device according to claim 1, characterized in that It further includes: a laser indicator; The laser indicator is closely arranged adjacent to the ranging sensor; The laser indicator is used to calibrate the corresponding measurement position of the ranging sensor on the to-be-detected leaf.

3. The plant living leaf chlorophyll content detection device according to claim 1 or 2, characterized in that, The ranging module includes: three ranging sensors; The ranging sensors are arranged adjacent to the spectral sensor, and the three ranging sensors are not on a straight line.

4. The plant living leaf chlorophyll content detection device according to claim 3, wherein The three ranging sensors and the spectral sensor are in the same plane, and the three ranging sensors are distributed at right angles.

5. A method for detecting the chlorophyll content of living plant leaves implemented by the device for detecting the chlorophyll content of living plant leaves according to any one of claims 1-4, characterized in that, Including: Based on the distance data, determine the leaf inclination angle of the to-be-detected leaf; Based on the leaf surface image of the to-be-detected leaf, determine the leaf surface smoothness of the to-be-detected leaf; Based on the spectral data of the to-be-detected leaf, the leaf inclination angle, and the leaf surface smoothness of the to-be-detected leaf, according to the reflected light amplitude compensation and correction formula, determine the compensated reflected light amplitude of the to-be-detected leaf; The reflected light amplitude compensation and correction formula is: where n is the light wavelength, with the unit of nm; y n is the amplitude of the reflected light of the measured leaf after compensation when the light wavelength is n; θ is the longitudinal inclination angle of the leaf; α is the transverse inclination angle of the leaf; S is the smoothness of the leaf; D n / θ / α / S is the amplitude of the reflected light when the light wavelength is n; k n is the constant coefficient when the light wavelength is n; Based on the compensated reflected light amplitude of the to-be-detected leaf and the sunlight amplitude, determine the reflectivity of the to-be-detected leaf; Based on the reflectivity of the to-be-detected leaf, determine the chlorophyll content of the to-be-detected leaf.

6. The method for detecting the chlorophyll content of living plant leaves according to claim 5, characterized in that, The step of determining the leaf inclination angle of the to-be-detected leaf based on the distance data specifically includes: Based on the distance data, determine the longitudinal leaf inclination angle and the transverse leaf inclination angle of the to-be-detected leaf; Wherein, the longitudinal leaf inclination angle is the angle between the midrib direction of the leaf and the ground horizontal direction; the transverse leaf inclination angle is the angle between the direction perpendicular to the midrib of the leaf and the ground horizontal direction.

7. The method for detecting the chlorophyll content of living plant leaves according to claim 6, wherein The step of determining the leaf surface smoothness of the to-be-detected leaf based on the leaf surface image of the to-be-detected leaf specifically includes: Based on the leaf surface image of the leaf to be measured, obtain the grayscale image of the leaf surface of the leaf to be measured; Based on the grayscale image of the leaf surface, determine the standard deviation after normalizing the grayscale value of the leaf surface, and use the standard deviation after normalizing the grayscale value of the leaf surface as the smoothness of the leaf surface of the leaf to be measured.

8. The method for detecting the chlorophyll content of living plant leaves according to any one of claims 5-7, characterized in that, After the step of determining the reflectivity of the leaf to be measured based on the compensated reflected light amplitude of the leaf to be measured and the sunlight amplitude, the following steps are further included: Determine the data difference between the reflectivity of the leaf to be measured at the current preset light wavelength and the reflectivity of the leaf to be measured at the previous preset light wavelength; wherein, the preset light wavelength belongs to the near-infrared light range; If it is determined that the data difference is greater than the preset difference threshold, re-determine the sunlight amplitude.

Images