Bidirectional synchronous detection platform for plant perception mechanism and proximity physics and use method

Abstract

According to the plant perception mechanism and proximity physics bidirectional synchronous detection platform and the use method, a functional unit comprises a growth chamber system, an illumination system, a radiation detection system, a point cloud detection system and an angle control system, and the angle control system is used for controlling the detection angles of the illumination system, the radiation detection system and the point cloud detection system. The high-precision multi-angle measurement of illumination change, reflection attribute change and corresponding form adjustment of a target plant is supported. Therefore, the method not only can deduce the perception (phototropism and gravitational tropism) mechanism of the plant from the combined information of the received illumination change and the corresponding form adjustment, but also can analyze the proximity physics of the plant from the combined information of the received illumination change and the reflection attribute change in combination with the form record at the corresponding moment; based on a corresponding specific implementation method, the platform can realize bidirectional synchronous detection of a plant sensing mechanism and near sensing physics.

Description

Technical Field

[0001] The present invention relates to a two-way synchronous detection platform for plant perception mechanism and near-sensing physics and a use method thereof, and relates to the field of plant remote sensing and plant perception. Background Art

[0002] Plant close-up physics: The surface reflectance of plant leaves can accurately quantify the biochemical parameters of plant leaves, and then reflect the growth and nutritional status of plants. It has been widely used to evaluate the carbon cycle in various terrestrial ecosystems, such as precision agriculture and forestry. Under laboratory conditions, most leaves are cut from plants and immediately laid flat on the measuring instrument for observation. Previous studies have been quite sophisticated in the technology of obtaining leaf surface reflectance based on integrating sphere measurement and DHRF, and have derived high-precision directional-hemispherical reflectance models such as the PROSPECT-PRO model. In recent years, due to the emergence of leaf clips and close-range imaging spectrometers, BRF is more suitable for inverting leaf chlorophyll content than DHRF, and BRF has gradually been used to obtain plant leaf surface reflectance. However, under the same conditions, the BRF of the same leaf is slightly larger than the DHRF in the entire visible light region. This is because BRF includes the specular reflection component of the leaf, while DHRF is often measured in an integrating sphere, and the specular reflection component is averaged and weakened in the entire hemisphere space. Therefore, in DHRF, when the incident angle is small relative to the leaf normal, the specular reflection component can often be ignored, resulting in the value of DHRF often only depending on the diffuse reflection caused by the biochemical components inside the leaf. The specular reflection of vegetation leaves itself is the interaction between the leaf structure and photons. The two structures of the leaf surface, either concave or convex, mainly caused by the wax layer on the leaf surface and the veins, make the leaf have properties similar to specular reflection to solar radiation. If the influence of specular reflection is ignored, the model based on DHRF is directly used for chlorophyll inversion based on BRF. Studies have shown that the chlorophyll content will be seriously underestimated. Although some vegetation indices, such as normalized-difference (ND), double-difference ratios (DD) and red edge positions (REPs), are insensitive to specular reflection and can be used for DHRF spectral inversion of plant biochemical component contents, as well as BRF spectral inversion of plant biochemical component contents, the actual accuracy of the latter is still slightly lower than the inversion results of DHRF spectra, and are highly empirical, and the model effect depends on the training data set; similarly, although the existing BRF-based models can be used to describe the angular reflection characteristics of leaves, they focus more on the inversion of leaf structural parameters and do not consider the influence of internal biochemical components of leaves.

[0003] Plant perception mechanism: The biggest factors affecting plant growth are the gravity of the earth and the changes in hormones and cell structures in plants caused by light. In recent decades, researchers' interest in factors affecting plant growth has mainly focused on the cellular and molecular mechanisms of plant perception of environmental factors, and how plants transmit perceived signals to hormone gradients, especially auxin gradients to stimulate asymmetric growth. The gravitropism of plants can be explained by the apical dominance phenomenon of plants. Usually, the top of the main stem of a plant grows very fast, and the lateral buds grow very slowly or dormantly. This phenomenon of the main stem apex growth dominating, preventing the lateral buds from germinating or inhibiting the growth of lateral branches is called apical dominance. This phenomenon is common in the plant kingdom, but it varies greatly from plant to plant. At present, the cause of the apical dominance phenomenon is mostly attributed to the indirect inhibition theory of auxin caused by the apical bud and gravity. The indirect inhibition theory of auxin has certain experimental basis: after the top of the plant is removed, the lateral buds can grow rapidly. If lanolin containing auxin is applied to the incision after the top is removed, the lateral buds will also grow slowly, that is, the external application of auxin can replace the inhibitory effect of the apical bud on the lateral buds. However, some people have found in plants such as lupine that the content of auxin in the lateral buds inhibited by the apex is higher than the optimal concentration required for the growth of the lateral buds. It was also found that the lateral buds can grow when cytokinins are applied to the inhibited lateral buds (i.e., the apical dominance is relieved), so it is believed that the reason why the lateral buds are inhibited is that they do not have enough cytokinins. Cytokinins are synthesized in the roots, and the action of auxins produced by the apical buds may control the transport of cytokinins. Since the auxins of the apical buds are transmitted to the lateral buds through polar transport, the auxin concentration of the apical buds is lower than that of the lateral buds, and they become a reservoir of input substances, and they get cytokinins before the lateral buds. Due to the high auxin concentration, the lateral buds cannot get enough cytokinins, and their growth is inhibited. Therefore, due to the effect of gravity, a large amount of auxin is evenly transported from the apical buds along the main stem to the lateral branches, which leads to the main stem of woody plants growing almost vertically upward, while the growth of lateral buds is inhibited. For plants, phototropism is the growth activity induced by the response of plant organs to the stimulation of incident light in a certain direction. Normally, the phototropism of plants is a very slow growth process. Some plants can also change the posture of their leaves in a relatively short period of time to chase the daily changes in sunlight. The phototropism of plants is because the side of the main stem facing away from the light has more auxin and grows faster, while the side facing the light has less auxin and grows slower, so the top of the stem grows toward the light source. For plants that grow in the wild and receive even light, all parts of the stem receive the same amount of sunlight, and the auxin is evenly distributed, so the stem grows upright. For plants that grow with uneven light, the side facing the light receives stronger light, and the auxin on the side facing the light is transferred to the side facing away from the light, causing the main stem to bend toward the light source. Therefore, the phototropism of plants is related to the uneven distribution of auxin on the light-facing and backlight sides. Unidirectional light can cause auxin to move to the backlight side, causing the backlight side to grow faster than the light-facing side, and thus bend toward the light.The reason why auxin moves to the backlit side may be related to the potential difference caused by light at different parts of the organ tip. The light-facing side carries a negative charge, while the backlit side carries a positive charge. The weakly acidic auxin anions are attracted by the positive charge and move to the back, thus causing auxin to migrate inside the main stem.

[0004] In recent years, with the continuous development of remote sensing technology, a series of remote sensing instruments such as lidar and photometer with high-precision observation capabilities have emerged, but there is no comprehensive new technology to carry out the research on the perception mechanism of plant growth and its near-sensing physics. Therefore, making full use of point cloud data and photometer measurement data to jointly carry out two-way synchronous detection of plant perception mechanism and near-sensing physics can solve the bottleneck problem that was difficult to solve in previous plant physiology research and open a new era of botanical research. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, in view of the above problems, the purpose of the present invention is to provide a two-way synchronous detection platform and method for plant perception mechanism and near-sensing physics, which can accurately obtain the morphological and structural attributes of plants, and can quantitatively monitor plants in their original posture and growth state, avoiding the traditional method of obtaining plant biochemical attributes by destroying the plant.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution provided by the present invention is: In a first aspect, the present invention provides a two-way synchronous detection platform for plant perception mechanism and near-sensing physics, the platform comprising a growth chamber system, wherein the growth chamber system is provided with a lighting system, a radiation detection system, a point cloud detection system, an angle control system and a support platform; The growth chamber system is used to provide constant temperature and humidity for plants and effectively avoid the influence of external radiation on plant growth; The lighting system is used to provide the plants with an incident light source close to the solar spectrum and an isotropic parallel light source; The radiation detection system is used to obtain the photosynthetic radiation PAR received by the plant and measure the radiation value reflected by the plant; The point cloud detection system is used to observe the appearance changes and growth conditions of plants, and obtain the reflectivity of plant point clouds based on plant point cloud data to study plant structural characteristics and biochemical characteristics; The angle control system is used to control the angles of the lighting system, the radiation observation system and the point cloud observation system respectively, and explore the growth of plants under different incident angles; The support platform is used to provide physical support for the lighting system, radiation observation system and point cloud observation system.

[0007] Furthermore, the growth chamber system adopts a light-proof growth chamber, and blackout curtains are installed in the growth chamber to provide a relatively closed space and reduce interference from natural light sources; the walls of the growth chamber are covered with black cloth, which can reduce errors caused by light reflection and multiple scattering on the walls, resulting in the non-light-facing surface of the plant being illuminated.

[0008] Furthermore, the support platform includes a support base plate, on which a base for placing plants is provided. The base can carry the plants and at the same time can drive the plants to rotate at different angles, so that the plants can rotate from a vertical state to an inclined state at different angles. A vertical support rod is provided on one side of the support base plate, and a horizontal support rod is provided on the upper part of the vertical support rod.

[0009] Further, the lighting system includes a neon tube, a searchlight and a support plate; At least one neon tube is arranged on the vertical support rod through the support plate as a light source for plant growth, and each neon tube is set to a mode that can be turned on independently to ensure that the irradiation light only comes from the side and bottom of the plant, which is convenient for distinguishing the gravitropism and phototropism of the tree, and the support plate is a dark plate; The searchlight is used to emit isotropic parallel light to illuminate the blades. The searchlight adopts an isotropic light source, and the spectrum emitted by the isotropic light source is close to the solar spectrum.

[0010] Further, the radiation observation system includes a photometer and a spectrometer; The photometer is used to measure the spectrum of the neon lamp tube with different powers, and to measure the light flux reaching the stem of the sapling and the radiation flux of blue light, which is the main radiation of photosynthesis, at different inclination angles; The spectrometer is used to measure the reflected radiation of the blade observed at different angles, and calculate the directional reflectivity and BRDF of the blade.

[0011] Furthermore, the point cloud observation system uses a laser radar to scan plant morphology to obtain plant point clouds, and obtain multi-band reflectivity of the point clouds, which is used to gain an in-depth understanding of the structural mechanisms and biochemical components inside the plant that affect tropistic growth.

[0012] Further, the angle control system adopts an annular device, which includes a rotatable and slidable first annular mechanical arm, a second annular mechanical arm and an annular track, and the ends of the first annular mechanical arm, the second annular mechanical arm and the annular track are movably connected to the transverse support rod, wherein: The searchlight is arranged on the first annular mechanical arm, which can not only ensure that the searchlight appears at different azimuths of the plant, but also present different zenith angles at different azimuths, which is more conducive to determining the directional reflection characteristics of the plant; The radiation receiving probe of the spectrometer is arranged on the second annular mechanical arm to ensure receiving the reflected radiation of the plant leaves at different azimuth angles and different zenith angles to obtain the BRDF characteristics of the plant; The photometer is arranged on the second annular mechanical arm and can measure the light flux reaching the stem of the sapling at different inclination angles; The laser radar, placed on the circular track, can completely scan the morphological characteristics of the entire plant.

[0013] Furthermore, the reference plate is arranged on the supporting platform, and the angle of the reference plate can be adjusted, so as to perform distance correction and radiation intensity correction on the photometer and the laser radar, and correct errors existing during use.

[0014] Furthermore, according to the BRDF characteristics of the leaves calculated by the PROSPECULAR model, the biochemical component content and the surface roughness of the leaves are estimated contactlessly. Since BRDF is the ratio of two minimum values, it cannot be obtained directly. First, the BRF of the leaves is calculated: The relationship between BRDF and BRF is as follows: ; in, is the BRDF of the Lambertian surface; ; in, and are the blade radiance and reference plate radiance measured at the same azimuth, is the reflectivity of the reference plate in this band.

[0015] In a second aspect, the present invention also provides a method for using a two-way synchronous detection platform for plant perception mechanism and near-sensing physics, including: The photometer directly measures the effective photosynthesis radiation received by the plant at different powers and different incident angles of the neon lamp, and obtains PAR and the radiation flux of blue light used for photosynthesis based on the integration of the tilt angle and the lamp power; Through the plant point cloud obtained by the laser radar, the changes in plant growth caused by the interaction of the plant's phototropism and gravitropism under the dual influence of gravity and light are observed, the inclination angle of the plant leaves relative to the incident light source is obtained, and at the same time, multi-band reflectivity data is obtained based on the scanned point cloud to study the response of the plant's reflective characteristics to different light source types, and determine the relationship between the plant structural parameters and biochemical component content related to the plant's reflective characteristics obtained based on the point cloud reflectivity data and the plant's tropistic growth; The directional reflection characteristics of leaves at different azimuths measured by searchlights at different angles and spectrometers can reflect the ecological attributes and biochemical content of the leaves, and further reflect the relationship between the biochemical state and growth status of the entire plant, thereby achieving a close physical quantitative study of the biochemical parameters of the entire plant.

[0016] The present invention adopts the above technical solution, and has the following characteristics: 1. The platform of the present invention integrates laser radar and photometer. On the one hand, based on the laser point cloud data obtained by the laser radar, it improves the error problem caused by the low-precision estimation measurement of the camera or the actual contact measurement of the plant morphological changes in the traditional plant perception mechanism research. On the other hand, based on the multi-dimensional plant reflectivity data, the internal structure information of the plant leaves and the content of the plant biochemical components are obtained contactlessly. The reflectivity data that can reflect the real-time internal structure changes and biochemical component content changes of the plant are creatively linked to the plant growth perception mechanism, solving the single-dimensional problem in the previous plant perception mechanism research.

[0017] 2. The present invention does not avoid observing the specular reflection component of plant leaf surface reflection in traditional quantitative remote sensing, but adopts multi-angle observation of plant leaf reflection, while considering the specular reflection component and diffuse reflection component of plant leaf reflection, and uses the PROSPECULAR model to separate the specular reflection and diffuse reflection of leaves. While allowing the existence of specular reflection, it can simultaneously invert the leaf surface structure parameters and the internal biochemical component content, thereby realizing the close physical quantitative study of the biochemical parameters of the whole plant.

[0018] 3. Traditional quantitative remote sensing research on single plants often focuses on single leaves of plants, which need to be destructively removed from the plant and quickly flattened on the measuring instrument to change its original structure, and then measure its reflectivity or biochemical content, and then obtain target information such as the health status and growth status of the whole plant. It cannot fully reflect the posture, structure and biochemical content of the plant in its original state. The present invention is equipped with a laser radar and a spectrometer that can observe from multiple angles, which can not only accurately obtain the morphological and structural attributes of the plant, but also can quantitatively monitor the plant in its original posture and growth state, avoiding the traditional means of obtaining plant biochemical attributes by destroying the plant, and creatively coupling the monitoring of plant growth characteristics (phototropism and gravitropism) with multi-angle remote sensing observations, and then exploring the relationship between the biochemical content of plant leaves, leaf structural parameters and growth trends.

[0019] In summary, the present invention can be widely used in plant mechanism research. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components. In the accompanying drawings: Figure 1 It is a schematic diagram of the principle of a two-way synchronous detection platform of plant perception mechanism and near-sensing physics according to an embodiment of the present invention; Figure 2 It is a structural diagram of a two-way synchronous detection platform for plant perception mechanism and near-sensing physics according to an embodiment of the present invention; Figure 3 The present invention is a flowchart of data collection and data processing for a two-way synchronous detection platform for plant perception mechanism and near-sensing physics according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0022] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0023] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside", "outside", "inner side", "outer side", "below", "above", etc. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0024] Since there is no comprehensive new technology to study the perception mechanism of plant growth and its near-sensory physics, the present invention provides a two-way synchronous detection platform for plant perception mechanism and near-sensory physics and a method of use, including a growth chamber system, in which a lighting system, a radiation detection system, a point cloud detection system, an angle control system and a support platform are arranged; the growth chamber system is used to provide plants with a constant temperature and humidity, and effectively avoid the influence of external radiation on plant growth; the lighting system is used to provide plants with an incident light source close to the solar spectrum and an isotropic parallel light source; the radiation detection system is used to obtain the photosynthetic radiation PAR received by the plant and measure the radiation value reflected by the plant; the point cloud detection system is used to observe the appearance changes and growth of the plant, and obtain the reflectivity of the plant point cloud based on the point cloud data of the plant to study the structural characteristics and biochemical characteristics of the plant; the angle control system is used to control the angles of the lighting system, the radiation observation system and the point cloud observation system respectively, and explore the growth of the plant under different incident angles; the support platform is used to provide physical support for the lighting system, the radiation observation system and the point cloud observation system. Therefore, the present invention can accurately obtain the morphological and structural properties of plants, and can quantitatively monitor plants in their original posture and growth state, avoiding the traditional method of obtaining plant biochemical properties by destroying the plants.

[0025] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0026] Embodiment 1: Figure 1 As shown, the bidirectional synchronous detection platform of plant perception mechanism and near-sensing physics provided in this embodiment includes a growth chamber system 1, a lighting system 2, a radiation observation system 3, a point cloud observation system 4, an angle control system 5 and a support platform 6.

[0027] The growth chamber system 1 is used to provide constant temperature and humidity for plants, effectively avoid the influence of external radiation (mainly natural sunlight) on plant growth and reduce multiple scattering in the room.

[0028] The lighting system 2 is used to provide the plants with an incident light source close to the solar spectrum and an isotropic parallel light source.

[0029] The radiation detection system 3 is used to obtain the photosynthetically active radiation PAR (Photosynthetically active radiation) received by the plant and measure the radiation value reflected by the plant.

[0030] The point cloud detection system 4 is used to observe the appearance changes and growth conditions of plants, and obtain the reflectivity of the plant point cloud based on the plant point cloud data to study the plant structural characteristics and biochemical characteristics.

[0031] The angle control system 5 is used to control the angles of the lighting system 2, the radiation observation system 3 and the point cloud observation system 4 respectively, so as to explore the growth conditions of plants under different incident angles.

[0032] The support platform 6 is used to provide physical support for the lighting system 2 , the radiation observation system 3 and the point cloud observation system 4 .

[0033] In a preferred embodiment of the present invention, the growth chamber system 1 may be a light-proof growth chamber, in which a lighting system 2, a radiation observation system 3, a point cloud observation system 4 and an angle control system 5 are arranged.

[0034] Furthermore, blackout curtains are installed in the growth room, which can provide a relatively closed space and reduce interference from natural light sources.

[0035] Furthermore, the walls of the growth chamber are covered with black cloth, which can reduce the error caused by the reflection and multiple scattering of light on the walls, resulting in the non-light-facing surface of the plant being illuminated.

[0036] Furthermore, the growth chamber needs to fully control the temperature and humidity to ensure that a constant environment can be provided. The specific implementation process can be controlled as needed. For example, the humidity control of the growth chamber is mainly based on the humidity sensor to monitor the humidity of the growth chamber. The humidifier and dehumidifier can be used to adjust the working intensity according to the current humidity level. The humidity sensor can be connected to a control system to automatically enable or disable the humidifier or dehumidifier through the control system. The temperature control of the growth chamber mainly depends on the air conditioning system and the ventilation system. The air conditioning system sets a constant temperature range. Usually, the optimal temperature for plant growth is between 18°C ​​and 25°C. At the same time, a ventilation system is installed to ensure air circulation and prevent the indoor temperature from being too high. In addition, in cold seasons, a heater can be used in the growth chamber to maintain the room temperature. The heater is equipped with a temperature control device to avoid excessively high or low temperatures.

[0037] In a preferred embodiment of the present invention, Figure 2As shown, the support platform 6 includes a support base plate 61, and a base 62 for placing plants is arranged on the support base plate 61. The base 62 can carry the plants and can drive the plants to rotate at the same time, so that the plants rotate from a vertical state to an inclined state at different angles. A vertical support rod 63 is arranged on one side of the support base plate 61, and a horizontal support rod 64 is arranged on the upper part of the vertical support rod 63. The purpose of installing the plants on the base 62 that can be tilted at different angles is to explore the single effect of gravitropism on the tropistic growth of plants and the combined effect of gravitropism and phototropism on the tropistic growth of plants.

[0038] Furthermore, each growth chamber system can be equipped with multiple support platforms 6 as needed. Since observing the phototropism and gravitropism of plant growth by relying on only one sample will result in too large accidental errors, multiple platforms and multiple plants of the same type can be placed in the growth chamber to observe the growth tropism of plants, thereby reducing the impact of accidental errors. If multiple similar growth chamber systems can be used at the same time, multiple groups of plants can be tested at the same time, which can be set up as needed, and will not be described in detail here.

[0039] In a preferred embodiment of the present invention, the lighting system 2 includes a neon lamp 21, a support plate 22 and a searchlight 23. The neon lamp 21 of this embodiment is a ring-shaped neon lamp 21, which is taken as an example and is not limited thereto.

[0040] A circular neon tube 21 is provided on the vertical support rod 63 through the support plate 22 as a light source for plant growth. In this embodiment, two circular neon tubes 21 are vertically provided on the support plate 22. This is taken as an example, but is not limited thereto and can be provided according to actual needs. It should be noted that in this embodiment, circular neon tubes 21 of different powers arranged vertically in a row are used to simulate sunlight of different intensities. Each circular neon tube 21 is set to a mode that can be turned on independently to ensure that the irradiation light only comes from the side and below of the plant, so that the gravitropism (tree seedlings grow vertically upward) and phototropism (tree seedlings move toward the light source) of the trees can be distinguished more accurately.

[0041] Furthermore, the annular neon tube 21 is used to provide the plants with an incident light source close to the solar spectrum. The annular neon tube 21 can use different lighting powers as needed. The lighting power of the annular neon tube 21 can be controlled by replacing the annular neon tube, and 55 W, 40 W and 22 W can be selected. If a 15 W annular neon tube is required, a filter can be set in front of the 22 W annular neon tube to obtain it. The filter is detachable and is intended to provide a light source with other powers in addition to the fixed power.

[0042] Furthermore, the model of the annular neon lamp 21 may be OSRAM FC 865, which is taken as an example and is not limited thereto.

[0043] Furthermore, the support plate 22 is used to support and fix the annular neon tube 21. The support plate 22 can be made of a dark-colored plate, because a white plate will cause a large amount of reflected light to reach the wall of the growth chamber, ultimately causing multiple scatterings that result in the entire growth chamber being too bright, causing the light source received by the plants to not be an anisotropic light source from one side, while a dark-colored plate can absorb the radiation energy emitted by the light source to the support plate to a large extent.

[0044] Furthermore, the searchlight 23 is used to emit isotropic parallel light to illuminate the leaves. The searchlight 23 selects an isotropic light source. The selection of the isotropic light source is preferably close to the solar spectrum, because the incident solar light is an isotropic light source when it reaches the ground plants. The isotropic light source close to the solar spectrum is selected in the growth chamber just to achieve simulation in the growth chamber. The searchlight 23 is generally configured as a plurality of circular lamp tubes placed in parallel. The main function is to provide plant growth. The searchlight 23 is also preferably able to emit close to the solar spectrum. The light source is generally small in diameter, which can ensure a small scattering loss, and is used as a light source for obtaining plant reflectance data. In order to illuminate the leaves with parallel incident light, this embodiment ensures that the incident light source is unidirectional, which is convenient for calculating the BRF of the leaves, and then obtaining the direction-direction reflection characteristics of the leaves.

[0045] In a preferred embodiment of the present invention, the radiation observation system 3 includes a photometer 31 and a spectrometer 32 .

[0046] The photometer 31 is used to measure the spectrum of the annular neon tube 21 with different powers. The photometer 31 measures the light flux reaching the stem of the sapling at different tilt angles, which makes it possible to calculate the photosynthetic radiation (PAR). The photometer 31 is mainly used to measure the spectrum of the annular neon tube 21 with different powers (15W, 22W, 40W, 55W), and integrates the PAR and the radiation flux of blue light, which is the main radiation for photosynthesis, based on the tilt angle and the power of the tube.

[0047] The spectrometer 32 is used to measure the reflected radiation value of the plant. The spectrometer 32 is used to measure the reflected radiation of the leaves observed at different angles, and the direction-direction reflectivity and BRDF (bidirectional reflectance distribution function) of the leaves can be calculated. Among them, the direction-direction reflectivity represents that the solid angles of the incident radiation and the reflected radiation are close to 0, and it is generally defined as the ratio between the reflected radiation and the incident radiation; BRDF is a basic parameter that describes the spatial distribution of the reflection characteristics of the surface of an object, and mainly describes the characteristics of the reflectivity of the object changing with the incident direction and the reflection direction. Its size depends on the spectral characteristics, spatial structure, and variables in the incident and reflection directions of the object itself.

[0048] In a preferred embodiment of the present invention, the point cloud observation system 4 uses a laser radar 41 (LiDAR). The laser radar 41 is used to scan the plant morphology and obtain the point cloud, and obtain the multi-band reflectivity of the point cloud. On the one hand, the laser radar is used to observe the diameter growth changes of the plant stem, and observe the tropism growth of the plant by observing the morphological changes of the plant; on the other hand, it is used to obtain the multi-band reflectivity of the point cloud. The present invention uses a laser radar not only to obtain the three-dimensional morphology of the plant by scanning the target, but also each point cloud after scanning carries the reflectivity of multiple bands of the target in the visible light-near infrared range, which can deeply understand the deep structural mechanism inside the plant and the influence of biochemical components on tropism growth.

[0049] Furthermore, if Figure 3 As shown, after the laser radar 41 acquires the plant morphological data, it needs to go through point cloud registration, point cloud repair and thinning, point cloud denoising, point cloud feature extraction, point cloud segmentation, point cloud classification and other processing according to the data quality, and the obtained plant point cloud can be put into use. For example, before the trend growth is not detected for two consecutive weeks, the trend growth is represented by the daily average diameter growth rate at 10 cm from the base of the plant stem obtained by the laser radar using the point cloud every 2 to 3 days and the shape fitting curve formed by point cloud fitting.

[0050] In a preferred embodiment of the present invention, a reference board is also included. The reference board can be set on the supporting platform 6. The specific position is not limited as long as it does not affect the plant's ability to receive light. When the reference board is fixed, the radiation angle can be adjusted to perform distance correction and radiation intensity correction on the data of the photometer 31 and the laser radar 41, so as to correct errors that exist during the use of the instrument.

[0051] In a preferred embodiment of the present invention, the angle control system 5 includes an annular device capable of controlling different angles of the searchlight 23, the photometer 31, the spectrometer 32 and the lidar 41, the annular device includes a first annular robot arm 51, an annular track 52 and a second annular arm 53, and the ends of the first annular robot arm 51, the annular track 52 and the second annular robot arm 53 are movably connected to the transverse support rod 64, wherein the annular device surrounds all systems except the growth chamber system, ensuring that all morphological structures and posture changes of the plant can be completely scanned.

[0052] Furthermore, the searchlight 23 is arranged on a rotatable and slidable first annular mechanical arm 51, which can not only ensure that the searchlight appears at different azimuths of the plant, but also present different zenith angles at different azimuths, which is more conducive to determining the directional reflection characteristics of the plant.

[0053] Furthermore, the photometer 31 is disposed on a rotatable and slidable second annular mechanical arm 53 , and the photometer 31 mainly acquires radiation through a probe.

[0054] Furthermore, the radiation receiving probe of the spectrometer 32 is arranged on a rotatable and slidable second annular mechanical arm 53, so as to ensure that the reflected radiation of the plant leaves at different azimuth angles and different zenith angles is received, so as to facilitate the acquisition of the BRDF characteristics of the plant.

[0055] Furthermore, the laser radar 41 is placed on a rotatable and slidable circular track 52, and can completely scan the morphological characteristics of the entire plant.

[0056] In a preferred embodiment of the present invention, for the common model for simulating the reflectivity of leaves, the PROSPECT model, the input condition of the model forward modeling is the biochemical component content of the leaves. The present invention adopts non-contact measurement for the leaves, so it can only be reversely inverted; and for the PROSPECT model inversion, the reflectivity and transmittance of the leaves are used to infer the biochemical component content of the leaves, but its input reflectivity is the direction-hemispherical reflectivity, that is, how a single light source measures the reflectivity of the leaves in the integrating sphere, and the reflectivity in the present invention is the direction-direction reflectivity. If the specular reflection component is ignored, it will cause a serious misestimation of the biochemical component content of the leaves. The prior art proposes a PROSPECULAR model, which couples the PROSEPCT model with a specular reflection function, and completely divides the reflected radiation into the specular reflection component and the diffuse reflection component. It can not only evaluate the leaf surface roughness that causes the specular reflection of the leaves, but also evaluate the biochemical component content of the leaves according to the diffuse reflection component, which can be well adapted to the present invention. Therefore, the present invention abandons the idealized PROSPECT model in traditional research, and adopts a more accurate PROSPECULAR model to simulate the reflectivity of leaves, reflecting the structure and biochemical composition of plant leaves. The present invention can obtain the morphological and posture information of leaves. The morphological information of leaves mainly refers to the shape, size (width, thickness, etc.), structure, veins, surface texture, etc. of leaves; the posture information of leaves mainly refers to the inclination angle, arrangement, twisting or bending, and orientation of leaves relative to the normal. Therefore, the azimuth angle of the leaves when receiving searchlight radiation can be constructed, and the BRDF characteristics of the leaves calculated by the PROSPECULAR model can be used to estimate the biochemical content of the leaves and the surface roughness of the leaves without contact. It should be noted that since BRDF is the ratio of two minimum values, it cannot be obtained directly, and the BRF of the leaves needs to be calculated first.

[0057] The relationship between BRDF and BRF is as follows: ; in, is the BRDF of a Lambertian surface.

[0058] The final result often depends on the actual measurement result, namely BRF: ; in, and They are respectively the blade radiance and the reference plate radiance measured at the same azimuth angle, which requires that the reference plate in the present invention can also be rotated by a certain angle; is the reflectivity of the reference plate in this band.

[0059] In summary, in terms of monitoring plant growth and exploring plant perception mechanisms, the plant perception mechanism and near-sensing physics bidirectional synchronous detection platform of the present invention is set in a growth room environment with stable temperature and humidity. The incident radiation is emitted by a neon tube installed on a dark plate and reaches the plant and photometer through short-distance air transmission. The photometer can directly measure the photosynthetic radiation (PAR) received by the plant. Every 2-3 days, the growth status of the plant is scanned by a laser radar, and the point cloud obtained by the scan can realize non-contact and accurate measurement of the stem diameter of the plant and the morphological changes caused by the tropism of growth.

[0060] Embodiment 2: A method for using the two-way synchronous detection platform for plant perception mechanism and near-sensing physics provided by the present invention includes: S1. Directly measure the effective photosynthesis radiation received by the plant at different powers and incident angles of the annular neon lamp 21 by means of a photometer 31, and obtain PAR and the radiation flux of blue light, which is the main radiation for photosynthesis, based on the integral of the tilt angle and the lamp power.

[0061] S2. The plant point cloud obtained by the laser radar 41 is used to observe the changes in plant growth caused by the interaction of the plant's phototropism and gravitropism under the dual influence of gravity and light, and at the same time obtain the inclination angle of the plant leaves relative to the incident light source; secondly, the point cloud scanned by the laser radar 41 of the present invention can obtain multi-band reflectivity data, which can not only be compared with the plant reflectivity factor obtained by ordinary light sources to study the response of plant reflectivity characteristics to different light source types, but also on this basis, the relationship between plant structural parameters and biochemical component content related to plant reflectivity characteristics obtained based on point cloud reflectivity data and plant tropism growth can be explored.

[0062] Furthermore, the spectral curve formed by the reflectivity of plant leaves at 400nm-2500nm can reflect their health status, structural properties and biochemical component content. There are already a large number of leaf reflectivity models that can invert their various attribute values ​​based on the measured reflectivity. This platform can continuously invert the plant structural parameters and biochemical component content at different growth moments based on the reflectivity obtained by continuous non-contact measurement, and establish a relationship between their changes and the plant's tropism for growth.

[0063] S3. The directional reflection characteristics of the leaves at different azimuths measured by the searchlights 23 and the spectrometer 32 at different angles can reflect the ecological attributes and biochemical component content of the leaves to a certain extent, and further reflect the relationship between the biochemical state and growth status of the entire plant.

[0064] Furthermore, since the specular radiation of leaves observed at multiple angles by the present invention does not contain information on biochemical components inside the leaves, according to the Fresnel formula, this part of the radiation is partially polarized light, so the present invention can also be used for the study of polarization remote sensing, which will help deepen the polarization observation methods and laws of vegetation remote sensing, such as how the leaf inclination distribution function affects the polarization reflection characteristics of vegetation, and then affects the inversion of vegetation biochemical parameters. At the same time, the multi-angle polarization data of plants obtained by the present invention can further analyze the polarization reflection and filtering characteristics of vegetation at different observation scales. If it can be effectively considered in the quantitative remote sensing model, it can be used to explore the hot spot effect of vegetation remote sensing and the absorption, single and multiple scattering intensity characteristics of electromagnetic waves in different bands of vegetation, improve the accuracy of the existing polarization reflectivity model, and then extend and develop the existing known polarization effect of light in the vegetation canopy, which will help improve the accuracy of the existing canopy biochemical parameter inversion model of trees, forests, etc., and thus better understand the carbon sink and carbon cycle of the global forest system. In addition, the present invention can accurately measure and provide hyperspectral reflectance data for multi-angle observation of plants. There is currently almost no corresponding public dataset type available for this type of data, and this type of multi-angle dataset can solve many of the current problems that restrict the development of vegetation remote sensing.

[0065] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In the description of this specification, the description of reference terms "a preferred embodiment", "further", "specifically", "in the present embodiment", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of this specification. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples without contradiction.

[0066] 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 it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-way synchronous detection platform for plant perception mechanism and near-sensory physics, characterized in that: The platform includes a growth chamber system, in which a lighting system, a radiation detection system, a point cloud detection system, an angle control system and a support platform are arranged; The growth chamber system is used to provide constant temperature and humidity for plants and effectively avoid the influence of external radiation on plant growth; The lighting system is used to provide the plants with an incident light source close to the solar spectrum and an isotropic parallel light source; The radiation detection system is used to obtain the photosynthetic radiation PAR received by the plant and measure the radiation value reflected by the plant; The point cloud detection system is used to observe the appearance changes and growth conditions of plants, and obtain the reflectivity of plant point clouds based on plant point cloud data to study plant structural characteristics and biochemical characteristics; The angle control system is used to control the angles of the lighting system, the radiation observation system and the point cloud observation system respectively, and explore the growth of plants under different incident angles; The support platform is used to provide physical support for the lighting system, radiation observation system and point cloud observation system.

2. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 1 is characterized in that: The growth chamber system adopts a light-proof growth chamber, and blackout curtains are installed in the growth chamber to provide a relatively closed space and reduce interference from natural light sources; the walls of the growth chamber are covered with black cloth, which can reduce errors caused by light reflection and multiple scattering on the walls, resulting in the non-light-facing surface of the plant being illuminated.

3. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 1 is characterized in that: The support platform includes a support base plate, on which a base for placing plants is arranged. The base can carry the plants and at the same time can drive the plants to rotate at different angles, so that the plants can rotate from a vertical state to an inclined state at different angles. A vertical support rod is arranged on one side of the support base plate, and a horizontal support rod is arranged on the upper part of the vertical support rod.

4. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 3 is characterized in that: The lighting system includes a neon tube, a searchlight and a support plate; At least one neon tube is arranged on the vertical support rod through the support plate as a light source for plant growth, and each neon tube is set to a mode that can be turned on independently to ensure that the irradiation light only comes from the side and bottom of the plant, which is convenient for distinguishing the gravitropism and phototropism of the tree, and the support plate is a dark plate; The searchlight is used to emit isotropic parallel light to illuminate the blades. The searchlight adopts an isotropic light source, and the spectrum emitted by the isotropic light source is close to the solar spectrum.

5. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 4 is characterized in that: The radiation observation system includes a photometer and a spectrometer; The photometer is used to measure the spectrum of the neon lamp tube with different powers, and to measure the light flux reaching the stem of the sapling and the radiation flux of blue light, which is the main radiation of photosynthesis, at different inclination angles; The spectrometer is used to measure the reflected radiation of the blade observed at different angles, and calculate the directional reflectivity and BRDF of the blade.

6. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 5 is characterized in that: The point cloud observation system adopts a laser radar to scan the plant morphology to obtain the plant point cloud, and obtains the multi-band reflectivity of the point cloud, so as to deeply understand the influence of the internal structural mechanism and biochemical components of the plant on the tropism growth.

7. The two-way synchronous detection platform of plant perception mechanism and near-sensing physics according to claim 6 is characterized in that: The angle control system adopts an annular device, which includes a rotatable and slidable first annular mechanical arm, a second annular mechanical arm and an annular track, and the ends of the first annular mechanical arm, the second annular mechanical arm and the annular track are movably connected to the transverse support rod, wherein: The searchlight is arranged on the first annular mechanical arm, which can not only ensure that the searchlight appears at different azimuths of the plant, but also present different zenith angles at different azimuths, which is more conducive to determining the directional reflection characteristics of the plant; The radiation receiving probe of the spectrometer is arranged on the second annular mechanical arm to ensure receiving the reflected radiation of the plant leaves at different azimuth angles and different zenith angles to obtain the BRDF characteristics of the plant; The photometer is arranged on the second annular mechanical arm and can measure the light flux reaching the stem of the sapling at different inclination angles; The laser radar, placed on the circular track, can completely scan the morphological characteristics of the entire plant.

8. According to the bidirectional synchronous detection platform of plant perception mechanism and near-sensing physics described in claim 7, it also includes a reference board, which is arranged on the supporting platform. The angle of the reference board can be adjusted to perform distance correction and radiation intensity correction on the photometer and lidar, and correct errors existing during use.

9. The two-way synchronous detection platform of plant perception mechanism and near-sensory physics according to claim 8 is characterized in that: According to the BRDF characteristics of the leaves calculated by the PROSPECULAR model, the biochemical component content and the surface roughness of the leaves are estimated contactlessly. Since BRDF is the ratio of two minimum values, it cannot be obtained directly. First, the BRF of the leaves is calculated: The relationship between BRDF and BRF is as follows: ； in, is the BRDF of the Lambertian surface; ； in, and are the blade radiance and reference plate radiance measured at the same azimuth, is the reflectivity of the reference plate in this band.

10. A method for using a two-way synchronous detection platform based on the plant perception mechanism and near-sensing physics according to any one of claims 7 to 9, characterized in that: include: The photometer directly measures the effective photosynthesis radiation received by the plant at different powers and different incident angles of the neon lamp, and obtains PAR and the radiation flux of blue light used for photosynthesis based on the integration of the tilt angle and the lamp power; Through the plant point cloud obtained by the laser radar, the changes in plant growth caused by the interaction of the plant's phototropism and gravitropism under the dual influence of gravity and light are observed, the inclination angle of the plant leaves relative to the incident light source is obtained, and at the same time, multi-band reflectivity data is obtained based on the scanned point cloud to study the response of the plant's reflective characteristics to different light source types, and determine the relationship between the plant structural parameters and biochemical component content related to the plant's reflective characteristics obtained based on the point cloud reflectivity data and the plant's tropistic growth; The directional reflection characteristics of leaves at different azimuths measured by searchlights at different angles and spectrometers can reflect the ecological attributes and biochemical content of the leaves, and further reflect the relationship between the biochemical state and growth status of the entire plant, thereby achieving a close physical quantitative study of the biochemical parameters of the entire plant.

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