Plant factory in-situ chlorophyll fluorescence detection system, control method and device

Abstract

The application provides a plant factory in-situ chlorophyll fluorescence detection system, a control method and a device. The chlorophyll fluorescence detection control module controls a mobile platform to move along an inspection route to a target detection station and stop, and controls a mechanical execution mechanism to drive a chlorophyll fluorescence imaging module to approach a target detection plant, and then controls the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target detection plant, obtains multi-state frame-level fluorescence measurement data of the target detection plant, and sends the data to a chlorophyll fluorescence data processing module to generate a plurality of chlorophyll fluorescence parameter maps of the target detection plant, so that the photosynthesis state of the plant is monitored in the process of automatic inspection of the plant factory, and the technical problem that the existing plant factory inspection system cannot accurately, reliably and repeatedly evaluate the photosynthesis state of the plant is solved.

Description

Technical Field

[0001] This application relates to the field of plant phenotypic detection technology, and in particular to an in-situ chlorophyll fluorescence detection system, control method and device for plant factories. Background Technology

[0002] During photosynthesis, the light energy absorbed by plant leaves is primarily used for photochemical reactions or dissipated as heat and chlorophyll fluorescence. There is a competitive energy allocation relationship among photochemical reactions, heat dissipation, and chlorophyll fluorescence emission. When the photosynthetic state of a plant changes, the open state of the photosystem II reaction center, the efficiency of photochemical reactions, and the level of non-photochemical dissipation also change, further causing changes in chlorophyll fluorescence intensity and its dynamic characteristics. Therefore, detecting chlorophyll fluorescence signals under specific light conditions can be used to evaluate the photosynthetic state of a plant.

[0003] Pulse-modulated chlorophyll fluorescence measurement technology utilizes a combination of different functional light sources, including measurement light, action light, saturated pulse light, and far-red light, to induce different physiological states in plant leaves. Chlorophyll fluorescence images under these different physiological states are then captured by a camera to obtain key chlorophyll fluorescence parameters. These parameters are used to calculate photosynthetic physiological indicators such as maximum photochemical quantum efficiency, actual photochemical quantum efficiency, and non-photochemical quenching coefficient, thereby reflecting the photochemical reaction efficiency and non-photochemical energy dissipation state of plant leaves. Therefore, compared to red, green, and blue images that primarily characterize plant appearance, color, and morphology; hyperspectral images that primarily characterize spectral reflectance or absorption characteristics; and single fluorescence intensity maps that only characterize fluorescence intensity, pulse-modulated chlorophyll fluorescence measurement results have a clearer physiological meaning and are suitable for assessing and monitoring the photosynthetic state of plants in plant factories.

[0004] Most existing plant factories use inspection systems to monitor plants regularly. However, these systems mainly collect hyperspectral images and red-green-blue images, which can only record the plant's appearance color, canopy morphology, reflectance spectrum, and environmental changes. They do not integrate pulse-modulated chlorophyll fluorescence measurement technology, making it difficult to obtain key chlorophyll fluorescence parameters and various photosynthetic physiological indicators of plants under different physiological states. They do not support the monitoring of the photosynthetic state of plants.

[0005] More importantly, simply mounting the fluorescent camera onto the mobile platform of the inspection system still presents the following problems:

[0006] First, most existing chlorophyll fluorescence imaging devices are desktop, fixed, or darkroom type, requiring manual placement of plant samples, which is difficult to adapt to scenarios such as multi-layer cultivation racks, narrow channels, continuous supplemental lighting, and batch automatic inspection in plant factories.

[0007] Secondly, there are also interference factors at the plant factory site, such as red and blue supplemental lighting, metal frame reflection, white cultivation trough reflection, nutrient solution water surface reflection, leaf surface water droplet reflection, high humidity fogging, leaf shaking caused by fans, and limited space in multi-layer shelves. When the fluorescence camera collects chlorophyll fluorescence images, it will increase the fluorescence detection background, reduce the repeatability and reliability of the images, and thus affect the misjudgment of the photosynthetic status of the plants.

[0008] Furthermore, pulse-modulated chlorophyll fluorescence measurement technology requires strict coordination between the measurement light, the action light, the saturation pulse light, and the far-red light and the camera exposure window. If the various functional light sources are controlled solely by timing or ordinary triggering methods of the host computer software, camera trigger delays, uncertain exposure start times, changes in camera readout modes, changes in frame buffer status, or light source response delays may cause the measurement light pulse to not accurately fall into the camera's actual exposure window, or for the action light, saturation pulse light, and far-red light to reflect and leak into the detection channel. This would affect the accuracy of the acquired chlorophyll fluorescence images and consequently lead to misjudgments of the plant's photosynthetic state.

[0009] In summary, existing plant factory inspection systems struggle to accurately, reliably, and repeatedly assess plant photosynthetic status using pulse-modulated chlorophyll fluorescence measurement technology in multi-layered cultivation and complex optical interference environments. Summary of the Invention

[0010] In view of the shortcomings of the prior art described above, the purpose of this application is to provide an in-situ chlorophyll fluorescence detection system, control method and device for plant factories, which can solve the technical problem that existing plant factory inspection systems are unable to accurately, reliably and repeatably assess the photosynthetic status of plants.

[0011] To achieve the above and other related objectives, a first aspect of this application provides an in-situ chlorophyll fluorescence detection system for plant factories. The system includes: a mobile platform; a mechanical actuator mounted on the mobile platform, with a chlorophyll fluorescence imaging module at the end of the mechanical actuator; a chlorophyll fluorescence data processing module connected to the chlorophyll fluorescence imaging module; and a chlorophyll fluorescence detection control module connected to the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module, configured to control the mobile platform along a preset inspection path. The line moves within the plant factory and stops at the target detection station; the mechanical actuator is controlled to move the chlorophyll fluorescence imaging module closer to the target plant at the detection station, maintaining a preset working distance and measurement posture between the chlorophyll fluorescence imaging module and the target plant; the chlorophyll fluorescence imaging module is controlled to perform chlorophyll fluorescence imaging on the target plant, obtaining multi-state frame-level fluorescence measurement data of the target plant and sending it to the chlorophyll fluorescence data processing module; the chlorophyll fluorescence data processing module is controlled to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0012] In some embodiments of the first aspect of this application, the chlorophyll fluorescence imaging module includes at least: a fluorescence camera, configured to acquire multiple fluorescence frame images of the target plant under different physiological states within a real exposure window in response to a camera trigger signal; a multi-channel functional light source, including at least: a measurement light channel, an action light channel, a saturated pulse light channel, and a far-infrared light channel; each functional light source channel of the multi-channel functional light source is arranged around the imaging field of view of the fluorescence camera, such that the illumination area of ​​each functional light source channel coincides or substantially coincides with the imaging area of ​​the fluorescence camera; each functional light source channel includes at least: a light source driving unit, a functional light source, a current detection unit, a light output detection unit, and a temperature detection unit; a light shield, disposed outside the fluorescence camera and facing the imaging area of ​​the fluorescence camera and the light-emitting area of ​​the multi-channel functional light source, for forming a local light-shielding space above the target plant; and a distance detection unit is disposed on the light shield.

[0013] In some embodiments of the first aspect of this application, the chlorophyll fluorescence detection control module is provided with: a safety interlock unit connected to the mechanical actuator and the chlorophyll fluorescence imaging module, used to control the start of the chlorophyll fluorescence imaging module and determine whether the chlorophyll fluorescence imaging module meets preset chlorophyll fluorescence detection conditions. When the chlorophyll fluorescence imaging module does not meet the chlorophyll fluorescence detection conditions, the working state of the mechanical actuator or the chlorophyll fluorescence imaging module is adjusted until the chlorophyll fluorescence imaging module meets the chlorophyll fluorescence detection conditions, allowing the chlorophyll fluorescence imaging module to start chlorophyll fluorescence imaging of the target plant. The chlorophyll fluorescence detection conditions include at least: whether the working state of the fluorescence camera and the multi-channel functional light source is normal; whether the light shield is fully opened; and whether the distance and relative posture between the light shield and the target plant meet safe irradiation conditions and effective shading conditions.

[0014] In some embodiments of the first aspect of this application, the chlorophyll fluorescence detection control module is provided with: a hard real-time synchronization control unit; the hard real-time synchronization control unit is connected to the chlorophyll fluorescence imaging module and is used to control the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant according to a preset time sequence requirement; specifically, the method includes: initializing the fluorescence camera and each functional light source channel of the multi-channel functional light source; based on a preset clock cycle, controlling the fluorescence camera to perform an exposure operation to acquire fluorescence background frame images of the target plant and generate frame-level fluorescence background data; after the target plant enters a dark adaptation state, based on the clock cycle, the hard real-time synchronization control unit... The fluorescence camera and the multi-channel functional light source enter the dark-adapted fluorescence acquisition stage, acquiring dark-adapted fluorescence frame images of the target plant. Simultaneously, the hardware status metadata of the current chlorophyll fluorescence imaging module is acquired, generating frame-level dark-adapted fluorescence measurement data. The multi-channel functional light source is controlled to irradiate the target plant with a saturated pulse light signal, causing the target plant to enter the dark-state maximum fluorescence state. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real-time to enter the dark-state maximum fluorescence acquisition stage, acquiring dark-state maximum fluorescence frame images of the target plant. Simultaneously, the hardware status metadata of the current chlorophyll fluorescence imaging module is acquired, generating frame-level dark-state maximum fluorescence measurement data. Fluorescence measurement data; controlling the multi-channel functional light source to irradiate the target plant with the light signal, causing the target plant to enter a light-adapted state, and based on the clock cycle, hardware real-time synchronous control of the fluorescence camera and the multi-channel functional light source to enter the light-adapted fluorescence acquisition stage, acquiring light-adapted fluorescence frame images of the target plant, and simultaneously acquiring the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level light-adapted fluorescence measurement data; controlling the multi-channel functional light source to simultaneously irradiate the target plant with saturated pulse light signals and action light signals, causing the target plant to enter the maximum fluorescence state, and based on the clock cycle, hardware real-time synchronous control of the fluorescence camera and... The multi-channel functional light source enters the maximum fluorescence acquisition stage, acquiring the maximum fluorescence frame image of the target plant, and simultaneously acquiring the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level maximum fluorescence measurement data. The multi-channel functional light source is then controlled to irradiate the target plant with far-red light signals, causing the plant to enter the minimum fluorescence state. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are synchronously controlled in real-time to enter the minimum fluorescence acquisition stage, acquiring the minimum fluorescence frame image of the target plant, and simultaneously acquiring the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level minimum fluorescence measurement data.Based on the frame-level fluorescence background data, the frame-level dark-adapted fluorescence measurement data, the frame-level dark-state maximum fluorescence measurement data, the frame-level light-adapted fluorescence measurement data, the frame-level light-state maximum fluorescence measurement data, and the frame-level light-state minimum fluorescence measurement data, multi-state frame-level fluorescence measurement data of the target plant is generated.

[0015] In some embodiments of the first aspect of this application, the hard real-time synchronization control unit controls the fluorescence camera and each functional light source channel in a hard real-time synchronous manner, including: the hard real-time synchronization control unit sends a camera trigger signal to the fluorescence camera, so that the fluorescence camera responds to the camera trigger signal to start exposure and outputs an exposure feedback signal; in the dark-adapted fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel and the far-infrared light channel to remain closed, and after detecting the exposure feedback signal, controls the measurement light channel to output a measurement light signal to induce the target plant to produce chlorophyll fluorescence signal and read the chlorophyll fluorescence signal, so that the fluorescence camera acquires a dark-adapted fluorescence frame image within the actual exposure window; in the dark maximum fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel and the far-infrared light channel to remain closed, and after detecting the exposure feedback signal, controls the measurement light channel to output a measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, so that the fluorescence camera acquires a dark maximum fluorescence frame image within the actual exposure window; in the light-adapted fluorescence acquisition stage, the hard real-time synchronization control unit... The system controls the active light channel to continuously output an active light signal, keeps the saturated pulse light channel and the far-infrared light channel closed, and upon detecting the exposure feedback signal, synchronously controls the measurement light channel to output a measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, allowing the fluorescence camera to acquire light-adapted fluorescence frame images within the actual exposure window; during the maximum fluorescence acquisition phase, the hard real-time synchronization control unit controls the active light channel to continuously output an active light signal and keeps the far-infrared light channel closed, and upon detecting the exposure feedback signal, synchronously controls the saturated pulse light channel... The system outputs a saturated pulse light signal and a measurement light signal through the measurement light channel to read the chlorophyll fluorescence signal produced by the target plant, allowing the fluorescence camera to acquire the maximum fluorescence frame image within the actual exposure window. During the minimum fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel, and the far-infrared light channel to remain closed. Upon detecting the exposure feedback signal, the system controls the measurement light channel to output a measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, allowing the fluorescence camera to acquire the minimum fluorescence frame image within the actual exposure window.

[0016] In some embodiments of the first aspect of this application, the chlorophyll fluorescence detection control module further includes: a frame image quality control unit, connected to the chlorophyll fluorescence imaging module and the hard real-time synchronization control unit, respectively, for marking each fluorescence frame image as reliable, low reliable, or invalid based on preset fluorescence frame image quality control conditions at each fluorescence acquisition stage; wherein, the fluorescence frame image quality control conditions include at least: whether the fluorescence camera drops frames; whether the fluorescence frame image is overexposed; whether the fluorescence frame image is underexposed; whether the background of the fluorescence frame image is too high; whether the area of ​​interest of the fluorescence frame image is insufficient; whether the outline of the target plant in the fluorescence frame image is clear; whether the saturated pulse light signal is sufficient, whether the working light signal is stable, whether the non-working light signal is leaked, and whether the functional light source is overheated when acquiring the fluorescence frame image.

[0017] In some embodiments of the first aspect of this application, the chlorophyll fluorescence data processing module generates chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data in the following manner: performing image correction on each fluorescence frame image in the multi-state frame-level fluorescence measurement data to obtain multiple corrected fluorescence frame images; selecting a reliable corrected fluorescence frame image from each fluorescence acquisition stage as a key fluorescence frame image, and performing image registration on each key fluorescence frame image; performing image segmentation on each key fluorescence frame image to obtain one or more leaf regions of interest for each key fluorescence frame image, and removing strongly reflective areas and areas with poor light emission. In the focal region, one or more effective leaf regions of interest are obtained for each key fluorescence frame image; the pixel values ​​of each effective leaf region of interest in each key fluorescence frame image are extracted, and multiple chlorophyll fluorescence parameter maps of the target plant are generated; wherein each chlorophyll fluorescence parameter map includes at least: dark-adapted fluorescence parameter map, dark-state maximum fluorescence parameter map, light-adapted fluorescence parameter map, light-state maximum fluorescence parameter map, light-state minimum fluorescence parameter map, maximum photochemical quantum efficiency parameter map, actual photochemical quantum efficiency parameter map, non-photochemical quenching parameter map, light-adapted maximum photochemical quantum efficiency parameter map, compartment model photochemical quenching parameter map, and lake model photochemical quenching parameter map.

[0018] In some embodiments of the first aspect of this application, the chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest within the light adaptation key fluorescence frame image, and corrects the extracted pixel values ​​according to each light adaptation background frame image to obtain the light adaptation fluorescence signal value at each pixel position, thereby generating a light adaptation fluorescence parameter map of the target plant; the chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest within the light-maximum key fluorescence frame image, and corrects the extracted pixel values ​​according to each light-maximum background frame image to obtain the light-maximum fluorescence signal value at each pixel position, thereby generating a light-maximum fluorescence parameter map of the target plant.

[0019] To achieve the above and other related objectives, a second aspect of this application provides a method for controlling in-situ chlorophyll fluorescence detection in a plant factory. The method includes: a chlorophyll fluorescence detection control module applied to the in-situ chlorophyll fluorescence detection system described in any of the above embodiments; controlling a mobile platform to move along a preset inspection route within the plant factory and stop at a target detection station; controlling a mechanical actuator to move the chlorophyll fluorescence imaging module close to the target plant at the target detection station, maintaining a preset working distance and measurement posture between the chlorophyll fluorescence imaging module and the target plant; controlling the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant, obtaining multi-state frame-level fluorescence measurement data of the target plant and sending it to the chlorophyll fluorescence data processing module; and controlling the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0020] To achieve the above and other related objectives, a third aspect of this application provides an in-situ chlorophyll fluorescence detection device for plant factories. The device includes: a chlorophyll fluorescence imaging module connected to a plant factory inspection robot and detachably mounted on the mechanical actuator of the robot, the mechanical actuator being mounted on the robot's mobile platform; a chlorophyll fluorescence data processing module connected to the chlorophyll fluorescence imaging module; and a chlorophyll fluorescence detection control module connected to the chlorophyll fluorescence imaging module, the chlorophyll fluorescence data processing module, the robot's mobile platform, and the mechanical actuator, respectively, and configured... The process involves: controlling the mobile platform to move along a preset inspection route within the plant factory and stopping at the target detection station; controlling the mechanical actuator to move the chlorophyll fluorescence imaging module closer to the target plant at the detection station, ensuring that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant; controlling the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant, obtaining multi-state frame-level fluorescence measurement data of the target plant and sending it to the chlorophyll fluorescence data processing module; and controlling the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0021] As described above, this application has the following beneficial effects: This application provides an in-situ chlorophyll fluorescence detection system, control method, and device for plant factories. The chlorophyll fluorescence detection control module controls a mobile platform to move along the inspection route to the target detection station and stop. It also controls a mechanical actuator to bring the chlorophyll fluorescence imaging module closer to the target plant, thereby controlling the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant. This obtains multi-state frame-level fluorescence measurement data of the target plant, which is then sent to the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant. This enables the monitoring of the photosynthetic state of plants during automatic inspection in plant factories, solving the technical problem of existing plant factory inspection systems that make it difficult to accurately, reliably, and repeatedly assess the photosynthetic state of plants. Attached Figure Description

[0022] Figure 1 The diagram shown is a schematic representation of the structure of an in-situ chlorophyll fluorescence detection system for a plant factory according to one embodiment of this application.

[0023] Figure 2 The diagram shown is a structural schematic of a chlorophyll fluorescence imaging module in one embodiment of this application.

[0024] Figure 3 The diagram shown is a flowchart illustrating the in-situ chlorophyll fluorescence detection and control method in a plant factory according to one embodiment of this application.

[0025] Figure 4 The diagram shown is a flowchart of a hard real-time synchronous control chlorophyll fluorescence imaging method in one embodiment of this application.

[0026] Figure 5 This is a timing diagram illustrating the hard real-time synchronization control of the dark-adapted fluorescence acquisition stage, the dark-state maximum fluorescence acquisition stage, and the light-state minimum fluorescence acquisition stage in one embodiment of this application.

[0027] Figure 6 The diagram shows a timing sequence of hard real-time synchronization control during the preparation stage of maximum fluorescence acquisition in the dark state, as shown in one embodiment of this application.

[0028] Figure 7 The diagram shown is a timing schematic of the hard real-time synchronization control during the light adaptation acquisition preparation stage in one embodiment of this application.

[0029] Figure 8 The diagram shown is a timing schematic of the hard real-time synchronization control during the light-adaptive fluorescence acquisition stage in one embodiment of this application.

[0030] Figure 9 The diagram shows a timing sequence of hard real-time synchronization control during the preparation stage of maximum fluorescence acquisition in an embodiment of this application.

[0031] Figure 10 The diagram shown is a timing schematic of the hard real-time synchronization control during the maximum fluorescence acquisition stage of the optical state in one embodiment of this application.

[0032] Figure 11 The diagram shows a timing sequence of hard real-time synchronization control during the preparation stage of minimum fluorescence acquisition in one embodiment of this application.

[0033] Figure 12 The diagram shown is a schematic representation of the image processing flow in one embodiment of this application.

[0034] Figure 13 The diagram shown is a schematic representation of the in-situ chlorophyll fluorescence detection device for a plant factory according to one embodiment of this application. Detailed Implementation

[0035] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0036] In the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect, without limiting their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" do not necessarily imply that they are different.

[0037] To address the problems mentioned above in the background art, this application provides an in-situ chlorophyll fluorescence detection system, control method, and device for plant factories, aiming to solve the technical problem that existing plant factory inspection systems are unable to accurately, reliably, and repeatedly assess the photosynthetic status of plants.

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application are further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit this application.

[0039] like Figure 1 The diagram illustrates the structure of an in-situ chlorophyll fluorescence detection system for a plant factory according to an embodiment of this application. The in-situ chlorophyll fluorescence detection system for a plant factory in this embodiment mainly includes: a mobile platform, a mechanical actuator, a chlorophyll fluorescence imaging module, a chlorophyll fluorescence data processing module, and a chlorophyll fluorescence detection control module.

[0040] The mobile platform carries the mechanical actuator, the chlorophyll fluorescence imaging component, the chlorophyll fluorescence data processing module, and the chlorophyll fluorescence detection and control module. Plant factories typically have multi-layered cultivation racks with multiple cultivation layers along the height direction, each rack containing multiple plants. Multiple narrow passages are formed between adjacent cultivation racks. The mobile platform can move through these narrow passages within the plant factory.

[0041] In one embodiment, the mobile platform may be a free-moving robot, a track-mounted inspection platform, a lifting platform, a gantry mobile platform, or a multi-axis motion platform set on a fixed track. Users can choose according to their needs, and this application does not specifically limit the choice.

[0042] The mobile platform is equipped with a mechanical actuator, and a chlorophyll fluorescence imaging module is located at the end of the mechanical actuator. In one embodiment, as shown... Figure 1As shown, the mechanical actuator includes a multi-joint robotic arm. The chlorophyll fluorescence imaging module is disposed at the end of the multi-joint robotic arm. The multi-joint robotic arm is formed by connecting multiple joints and multiple robotic arm segments, and can coordinately adjust the position and orientation of the chlorophyll fluorescence imaging module to adapt to target plants located at different cultivation levels, and maintain a preset working distance and measurement orientation with target plants at different positions.

[0043] In other embodiments, the mechanical actuator may also be a six-axis robotic arm, a collaborative robotic arm, a Cartesian coordinate robot, a lifting and translation combination mechanism, or a swing arm mechanism. Users can choose according to their needs, and this application does not specifically limit the choice.

[0044] The chlorophyll fluorescence imaging module is used to perform chlorophyll fluorescence imaging on the target plant and obtain multi-state frame-level fluorescence measurement data of the target plant.

[0045] In one embodiment, such as Figure 2 As shown, the chlorophyll fluorescence imaging module includes at least: a mechanical connection interface, a fluorescence camera, a multi-channel functional light source, and a light shield.

[0046] The mechanical connection interface is used to carry the chlorophyll fluorescence imaging module and to detachably or fixedly connect it to the mechanical actuation structure. In one embodiment, the mechanical connection interface may be a threaded connection interface, a flange connection interface, a snap-fit ​​connection interface, a plug-in interface, or a group of mounting holes; this application is not specifically limited to these.

[0047] The fluorescence camera is used to acquire multiple fluorescence frames of the target plant under different physiological states within a real exposure window in response to a camera trigger signal. In one embodiment, the fluorescence camera may be a scientific complementary metal-oxide-semiconductor (sCMOS), a complementary metal-oxide-semiconductor camera (CMOS), a charge-coupled device (CCD), or other imaging devices with external triggering, linear image output, and exposure feedback functions.

[0048] In one embodiment, the fluorescence camera includes at least a lens and a filter assembly. The lens is located at the imaging end of the fluorescence camera and is used to receive chlorophyll fluorescence signals from the target plant and guide the received chlorophyll fluorescence signals to the image sensor of the fluorescence camera. The filter assembly is disposed in front of the lens and is used to filter the light signals from the target plant that are about to enter the lens, so as to suppress non-target light signals from entering the fluorescence camera, enabling the chlorophyll fluorescence signals to be effectively acquired by the fluorescence camera, reducing the interference of excitation light and ambient stray light on chlorophyll fluorescence imaging, improving the signal-to-noise ratio and contrast of the fluorescence frame images acquired by the fluorescence camera, thereby improving the accuracy of chlorophyll fluorescence detection of the target plant.

[0049] The multi-channel functional light source includes at least: a measuring light channel (ML), an acting light channel (AL), a saturation pulse light channel (SP), and a far-red light channel (FR). Each functional light source channel is arranged around the imaging field of view of the fluorescence camera, such that the illumination area of ​​each functional light source channel coincides with or substantially coincides with the imaging area of ​​the fluorescence camera.

[0050] Specifically, the measurement light channel (ML) is used to irradiate the leaves or local canopy of the target plant with a low-dose, short-pulse light signal within the true exposure window of the fluorescence camera to induce chlorophyll fluorescence signals, allowing the fluorescence camera to acquire multiple fluorescence frame images of the target plant under different physiological states. The action light channel (AL) is used to irradiate the leaves or local canopy of the target plant with a light signal of preset intensity and duration, causing the leaves or local canopy of the target plant to enter a light-adapted state. The saturation pulse light channel (SP) is used to irradiate the leaves or local canopy of the target plant with a high-intensity, short-pulse light signal, causing the Photosystem II (PSII) reaction center to tend to close within a short time, so that the target plant enters the dark-state maximum fluorescence state or the light-state maximum fluorescence state. The far-red light channel (FR) is used to irradiate the leaves or local canopy of the target plant with a medium-intensity, short-pulse far-red light signal, causing the Photosystem II reaction center to change from a closed state to an open state, so that the target plant enters the light-state minimum fluorescence state.

[0051] In one embodiment, each functional light source channel includes at least: a light source driving unit, a functional light source, a current detection unit, a light output detection unit, and a temperature detection unit. Specifically, the measurement light channel (ML) includes at least: a measurement light driving unit, a measurement light functional light source, a first current detection unit, a first light output detection unit, and a first temperature detection unit; the action light channel (AL) includes at least: an action light driving unit, an action light functional light source, a second current detection unit, a second light output detection unit, and a second temperature detection unit; the saturated pulse light channel (SP) includes at least: a saturated pulse light driving unit, a saturated pulse light functional light source, a third current detection unit, a third light output detection unit, and a third temperature detection unit; and the far-infrared light channel (FR) includes at least: a far-infrared light driving unit, a far-infrared light functional light source, a fourth current detection unit, a fourth light output detection unit, and a fourth temperature detection unit.

[0052] Each functional light source channel has a light source driving unit connected to its corresponding functional light source. This unit provides a driving current to the functional light source based on the light source control signal output by the chlorophyll fluorescence detection and control module, independently controlling the light source's on / off state, luminous intensity, and luminous timing. The sub-light source driving units for different functional light source channels are independent of each other, allowing the measurement light, action light, saturated pulse light, and far-red light to operate separately according to their respective fluorescence acquisition stages. Preferably, each light source driving unit can be implemented using hardware circuitry.

[0053] It should be noted that the specific wavelengths and signal parameters of each functional light source can be set and adjusted according to the plant species of the target plant, the transmission band of the filter component of the fluorescence camera, the spectral response range of the fluorescence camera, and the chlorophyll fluorescence detection experimental protocol. This application does not limit the specific settings.

[0054] The current detection unit of each functional light source channel is connected to the light source driving unit of that functional light source channel, specifically to the circuit output terminal of the light source driving unit. It is used to detect the driving current output by the light source driving circuit to the corresponding functional light source and generate the driving current information of the functional light source.

[0055] Each functional light source channel's light output detection unit is connected to the functional light source of that channel and includes at least a photodetector. The photodetector is located in the light-emitting area of ​​the functional light source and is used to detect the actual light signal output by the functional light source and generate light feedback information for the functional light source.

[0056] Each functional light source channel's temperature detection unit is connected to the functional light source of that channel and includes at least a temperature sensor. The temperature sensor is located at the position of the functional light source and is used to detect the operating temperature of the functional light source and generate operating temperature information for that functional light source.

[0057] The light shield is disposed on the outside of the fluorescence camera, specifically facing the imaging area of ​​the fluorescence camera and the light-emitting area of ​​the multi-channel functional light source. When the mechanical actuator drives the chlorophyll fluorescence imaging module to maintain a preset working distance and measurement posture with the target plant, it faces the target plant, forming a localized light-shielding space above the target plant. This reduces the amount of supplemental lighting from the plant factory and ambient reflected light entering the imaging field of the fluorescence camera, thereby reducing the image background caused by ambient light and the differences in ambient light between different detection stations. It also reduces the superposition interference of stray light on the chlorophyll fluorescence signal, ensuring more consistent acquisition conditions for fluorescence frame images obtained at different fluorescence acquisition stages, and improving the reliability and repeatability of chlorophyll fluorescence detection of the target plant. The light shield can adopt a contact type, proximity type, semi-enclosed type, retractable type, or flexible bonding structure; this application is not specifically limited to these.

[0058] In one embodiment, such as Figure 2 As shown, a distance detection unit is provided on the light-shielding cover. The distance detection unit faces the target plant and is located on the lower surface of the light-shielding cover. The distance detection unit is used to detect the distance and relative orientation between the light-shielding cover and the target plant, and generates distance detection information for the light-shielding cover. This distance detection information reflects the working distance and measurement orientation of the chlorophyll fluorescence imaging module. Preferably, the distance detection unit can be implemented using a non-contact distance sensor, such as a time-of-flight sensor, laser rangefinder, infrared rangefinder, or ultrasonic rangefinder; this application is not specifically limited to this type.

[0059] Based on the fluorescence frame images of the target plant acquired by the fluorescence camera, as well as the actual exposure window of the fluorescence camera, the pose information of the fluorescence camera, the distance detection information of the light shield, the driving current information of each functional light source, the light feedback information, and the operating temperature information obtained when acquiring each fluorescence frame image, multi-state frame-level fluorescence measurement data of the target plant is generated. The multi-state frame-level fluorescence measurement data includes at least: multiple fluorescence frame images, the sampling time of each fluorescence frame image, the actual exposure window of the fluorescence camera when acquiring each fluorescence frame image, the pose information of the fluorescence camera, the distance detection information of the light shield, the driving current information of each functional light source channel, the light feedback information, and the operating temperature information.

[0060] like Figure 1 As shown, the chlorophyll fluorescence imaging module is connected to the chlorophyll fluorescence data processing module. The chlorophyll fluorescence data processing module is used to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data acquired by the chlorophyll fluorescence imaging module.

[0061] Each chlorophyll fluorescence parameter diagram includes at least the following: dark-adapted fluorescence parameter diagram, dark-state maximum fluorescence parameter diagram, light-adapted fluorescence parameter diagram, light-state maximum fluorescence parameter diagram, light-state minimum fluorescence parameter diagram, maximum photochemical quantum efficiency parameter diagram, actual photochemical quantum efficiency parameter diagram, non-photochemical quenching parameter diagram, light-adapted maximum photochemical quantum efficiency parameter diagram, compartment model photochemical quenching parameter diagram, and lake model photochemical quenching parameter diagram.

[0062] like Figure 1 As shown, the chlorophyll fluorescence detection control module is connected to the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module, respectively. The chlorophyll fluorescence detection control module is configured to execute an in-situ chlorophyll fluorescence detection control method in a plant factory, controlling the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module to perform chlorophyll fluorescence detection on multiple plants at multiple detection stations within the plant factory.

[0063] like Figure 3 As shown, the chlorophyll fluorescence detection and control module executes the in-situ chlorophyll fluorescence detection and control method in plant factories, mainly including the following steps.

[0064] Step S1: Control the mobile platform to move along the preset inspection route within the plant factory and stop at the target inspection station.

[0065] In one embodiment, multiple testing stations can be set up in the plant factory, each testing station corresponding to a testing area, and each testing area includes multiple plants on multi-layer cultivation racks. A patrol route for the mobile platform is preset according to each testing station. Following the patrol route, the current testing station to be inspected is determined as the target testing station. When the mobile platform moves to the target testing station, it stops moving and remains stationary, so that the in-situ chlorophyll fluorescence detection system of the plant factory can perform chlorophyll fluorescence detection on one or more plants in the target testing area corresponding to the target testing station. After completing the chlorophyll fluorescence detection of each plant at the target testing station, the mobile platform continues to move along the patrol route to the next target testing station and stops.

[0066] It should be noted that users can determine the current inspection mode of the plant factory according to their needs, such as full-point inspection, key point spot inspection or rapid inspection, and thus determine the inspection route.

[0067] Step S2: Control the mechanical actuator to move the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant.

[0068] After the mobile platform stops at the target detection station, it identifies each plant to be detected within the corresponding target detection area as the target detection plant in sequence. The chlorophyll fluorescence detection control module controls the mechanical actuator to move the chlorophyll fluorescence imaging module to the vicinity of the target detection plant and adjusts the position and orientation of the chlorophyll fluorescence imaging module so that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement orientation with the target detection plant, so that the chlorophyll fluorescence imaging module can perform chlorophyll fluorescence imaging on the target detection plant. At this time, the light shield of the chlorophyll fluorescence imaging module faces the target detection plant, which can form a local light-shielding space above the target detection plant.

[0069] In one embodiment, the chlorophyll fluorescence detection control module includes a safety interlock unit. The safety interlock unit is connected to the mechanical actuator and the chlorophyll fluorescence imaging module, and is used to control the activation of the chlorophyll fluorescence imaging module, determine whether the chlorophyll fluorescence imaging module meets preset chlorophyll fluorescence detection conditions, and adjust the working state of the mechanical actuator or the chlorophyll fluorescence imaging module when the chlorophyll fluorescence imaging module does not meet the chlorophyll fluorescence detection conditions, until the chlorophyll fluorescence imaging module meets the chlorophyll fluorescence detection conditions.

[0070] Specifically, the chlorophyll fluorescence detection conditions include at least: whether the working status of components such as the fluorescence camera and the multi-channel functional light source of the chlorophyll fluorescence imaging module is normal; whether the light shield of the chlorophyll fluorescence imaging module is properly opened; and whether the distance and relative posture between the light shield of the chlorophyll fluorescence imaging module and the target plant meet the safe illumination conditions and the effective shading conditions. The safe illumination conditions are used to limit the minimum safe distance between the chlorophyll fluorescence imaging module and the target plant; the effective shading conditions are used to determine whether the light shield can form a local shading space above the target plant that meets the requirements of chlorophyll fluorescence imaging and achieve effective shading time.

[0071] The chlorophyll fluorescence imaging module is deemed to meet the chlorophyll fluorescence detection conditions if and only if all of the above conditions are met. In this case, the chlorophyll fluorescence imaging module is allowed to start chlorophyll fluorescence imaging of the target plant.

[0072] If any condition is not met, the chlorophyll fluorescence imaging module is deemed not to meet the chlorophyll fluorescence detection conditions. Specifically, if the working state of the fluorescence camera or the multi-channel functional light source of the chlorophyll fluorescence imaging module is abnormal, such as if a functional light source or detection unit is not turned on normally, then the chlorophyll fluorescence imaging module is determined to not meet the chlorophyll fluorescence detection conditions. The safety interlock unit prohibits the chlorophyll fluorescence imaging module from performing chlorophyll fluorescence imaging and controls the chlorophyll fluorescence imaging module to restart. If the light shield is not fully opened, then the chlorophyll fluorescence imaging module is determined to not meet the chlorophyll fluorescence detection conditions. The safety interlock unit prohibits the chlorophyll fluorescence imaging module from performing chlorophyll fluorescence imaging and controls the light shield to close and then reopen. If the light shield does not meet the safe illumination conditions or the effective light shielding conditions, then the chlorophyll fluorescence imaging module is determined to not meet the chlorophyll fluorescence detection conditions. The safety interlock unit prohibits the chlorophyll fluorescence imaging module from performing chlorophyll fluorescence imaging and controls the mechanical actuator to move the chlorophyll fluorescence imaging module to readjust the working position and measurement posture of the chlorophyll fluorescence imaging module to meet the requirements.

[0073] In this embodiment, the safety interlocking unit establishes a linkage constraint mechanism between the chlorophyll fluorescence imaging module and multiple safety conditions. This ensures that the chlorophyll fluorescence imaging module has reached a preset working distance and measurement posture before chlorophyll fluorescence imaging. Therefore, the risk of collision between the chlorophyll fluorescence imaging module and the target plant is reduced, and the impact of changes in working distance and measurement posture on fluorescence frame image acquisition is minimized, thereby improving the safety, accuracy, and consistency of chlorophyll fluorescence detection.

[0074] Step S3: Control the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module.

[0075] In one embodiment, the chlorophyll fluorescence detection and control module includes a hard real-time synchronization control unit. This hard real-time synchronization control unit is connected to the chlorophyll fluorescence imaging module, specifically to the fluorescence camera and the light source driving units of each functional light source channel. It controls the activation, deactivation, or short-term blanking of the corresponding functional light source by each light source driving unit, and controls the exposure of the fluorescence camera, thereby controlling the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant according to a preset timing requirement.

[0076] Preferably, the hard real-time synchronization control unit can employ a hardware controller with deterministic timing response capabilities, including but not limited to: FPGA (Field-Programmable Gate Array) chips, CPLD (Complex Programmable Logic Device) chips, real-time microcontrollers, real-time I / O units, and dedicated timing control chips. The hard real-time synchronization control unit can execute data acquisition, signal processing, and control command output according to a preset time base to ensure a stable time synchronization relationship and deterministic response delay between each control process, thereby achieving hard real-time synchronization between the fluorescence camera and each functional light source.

[0077] In one embodiment, the hard real-time synchronization control unit controls the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging of the target plant according to a preset timing requirement, including the following steps: Figure 4 As shown.

[0078] Step S31: Initialize the fluorescent camera and each functional light source channel of the multi-channel functional light source.

[0079] Specifically, the hard real-time synchronization control unit controls the fluorescence camera to disable automatic exposure, automatic gain, automatic white balance, gamma correction, noise reduction, and sharpening functions, and controls the output mode of the fluorescence camera to linear image output mode, so that the fluorescence camera outputs a linear image.

[0080] Simultaneously, the hard real-time synchronization control unit shuts down each functional light source channel, bringing each channel into its initial state. Specifically, the hard real-time synchronization control unit disconnects the hardware circuit of the light source driving unit for each functional light source channel, causing each driving unit to pause outputting driving current to the corresponding connected functional light source, thereby pausing the output of optical signals by each functional light source.

[0081] Step S32: Based on a preset clock cycle, control the fluorescence camera to perform an exposure operation to acquire fluorescence background frame images of the target plant and generate frame-level fluorescence background data.

[0082] Specifically, within a preset clock cycle, the hard real-time synchronization control unit sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to this trigger signal by starting exposure and outputting an exposure feedback signal. Under the action of this exposure feedback signal, the fluorescence camera opens its electronic shutter, allowing reflected light from the target plant to enter the lens and illuminate the image sensor, converting the reflected light into an electrical signal. This converted signal is then output as linear image data, i.e., the fluorescence background frame image.

[0083] In one embodiment, when all functional light source channels are in the off state, the hard real-time synchronization control unit can also control the fluorescence camera to perform exposure operations multiple times based on a preset clock cycle in order to acquire multiple frames of fluorescence background images of the target plant.

[0084] After the fluorescence camera outputs each frame of fluorescence background image, the hard real-time synchronization control unit is also used to generate frame-level fluorescence background data of the target plant based on each frame of fluorescence background image and the sampling time of each frame of fluorescence background image.

[0085] That is, the frame-level fluorescence background data includes: one or more frames of fluorescence background image and the sampling time of each frame of fluorescence background image.

[0086] In one embodiment, the clock period is set based on the response delay time, exposure time, and image readout time of the fluorescence camera. The clock period is greater than or equal to the sum of the response delay time, exposure time, and image readout time of the fluorescence camera, and can be adjusted by the user according to their needs.

[0087] Step S33: Once the target plant enters the dark adaptation state, based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real-time to enter the dark adaptation fluorescence acquisition stage, acquiring dark adaptation fluorescence frame images of the target plant, and simultaneously obtaining the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level dark adaptation fluorescence measurement data.

[0088] After the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant, the light shield can form a local shading space above the target plant. When the effective shading time reaches a preset condition, the target plant enters a dark adaptation state. At this time, the hard real-time synchronization control unit can hard real-time synchronize the fluorescence camera and the multi-channel functional light source to enter the dark adaptation fluorescence acquisition stage.

[0089] Specifically, after the target plant enters the dark adaptation state, within the clock cycle, the hard real-time synchronization control unit sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to this trigger signal by starting exposure and outputting an exposure feedback signal. Upon detecting this exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a low-dose, short-pulse measurement light signal to induce the target plant to produce chlorophyll fluorescence and read this signal. At this time, the measurement light signal can directly fall into the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire a dark-adapted fluorescence frame image of the target plant in the dark adaptation state within the true exposure window, thereby achieving hard real-time synchronization between the fluorescence camera and the measurement light channel (ML).

[0090] It should be noted that during the dark-adapted fluorescence acquisition stage, the hard real-time synchronization control unit keeps the active light channel (AL), the saturated pulse light channel (SP), and the far-infrared light channel (FR) closed at all times.

[0091] In one embodiment, during the dark-adapted fluorescence acquisition stage, the hard real-time synchronization control unit can also perform multiple hard real-time synchronization controls on the fluorescence camera, the active light channel (AL), the saturated pulse light channel (SP), the far-red light channel (FR), and the measurement light channel (ML) based on the clock cycle to acquire multiple dark-adapted fluorescence frame images of the target plant.

[0092] After the fluorescence camera outputs each frame of dark-adapted fluorescence frame image, the hard real-time synchronization control unit is also used to acquire the true exposure window of the fluorescence camera, the distance detection information of the light shield generated by the distance detection unit, the driving current information of the corresponding functional light source generated by each current detection unit, the light feedback information of the corresponding functional light source generated by each light output detection unit, and the operating temperature information of the corresponding functional light source generated by each temperature detection unit. Combined with each frame of dark-adapted fluorescence frame image and the sampling time of each frame of dark-adapted fluorescence frame image, frame-level dark-adapted fluorescence measurement data of the target plant is generated.

[0093] That is, the frame-level dark-adapted fluorescence measurement data includes: one or more dark-adapted fluorescence frame images, the sampling time of each dark-adapted fluorescence frame image, and hardware status metadata of the chlorophyll fluorescence imaging module when acquiring each dark-adapted fluorescence frame image. The hardware status metadata includes at least: the actual exposure window of the fluorescence camera when acquiring the dark-adapted fluorescence frame image, the pose information of the fluorescence camera, the distance detection information of the light shield, and the driving current information, light feedback information, and operating temperature information of each functional light source.

[0094] Furthermore, after the target plant enters the dark adaptation state, the timing of the hard real-time synchronization control within each clock cycle is illustrated with an example. For example... Figure 5As shown, at time T0, the hard real-time synchronization control unit keeps the active light channel (AL), the saturated pulse light channel (SP), and the far-infrared light channel (FR) closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to this trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting this exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal from times T2 to T4 to induce the target plant to produce chlorophyll fluorescence signals and read these signals. At this time, the exposure feedback signal of the fluorescence camera remains high, and the fluorescence camera maintains its exposure state; that is, the measurement light signal falls within the current true exposure window of the fluorescence camera, and the fluorescence camera acquires the dark-adapted fluorescence frame image. This dark-adapted fluorescence frame image contains the chlorophyll fluorescence signal of the target plant under dark-adapted conditions. The exposure feedback signal of the fluorescence camera ends before time T5, at which point image acquisition is complete. The hard real-time synchronization control unit begins acquiring hardware status metadata for this dark-adapted fluorescence frame image at time T5.

[0095] It should be noted that this timing control process is completed within the same clock cycle. That is, the clock cycle includes at least the time interval from T0 to T5.

[0096] Through the aforementioned timing control, the hard real-time synchronization control unit limits camera triggering, exposure feedback, functional light output, measurement light output, and hardware status metadata generation to a unified hardware timing sequence, ensuring that the measurement light output range falls within the exposure range of the fluorescence camera, and that each fluorescence frame image has corresponding light source status and exposure status information, thereby improving the accuracy and reliability of the acquired fluorescence frame images and enhancing the accuracy of chlorophyll fluorescence detection of the target plant.

[0097] Step S34: Control the multi-channel functional light source to irradiate the target plant with a saturated pulse light signal, causing the target plant to enter the dark-state maximum fluorescence state. Based on the clock cycle, control the fluorescence camera and the multi-channel functional light source to enter the dark-state maximum fluorescence acquisition stage in real time, acquire the dark-state maximum fluorescence frame image of the target plant, and at the same time obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level dark-state maximum fluorescence measurement data.

[0098] In one embodiment, after completing the dark adaptation fluorescence acquisition phase of the target plant, the hard real-time synchronization control unit controls the saturated pulse light channel (SP) to output a high-intensity short-pulse saturated pulse light signal, which is a periodic square wave pulse signal. After the saturated pulse light signal illuminates the target plant for a preset time, the target plant can enter the dark-state maximum fluorescence state. At this time, the hard real-time synchronization control unit can synchronously control the fluorescence camera and the multi-channel functional light source to enter the dark-state maximum fluorescence acquisition phase.

[0099] In one embodiment, after the target plant enters the dark-state maximum fluorescence state, within the clock cycle, the hard real-time synchronization control unit controls the saturated pulse light channel (SP) to close and synchronously sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal by starting exposure and outputting an exposure feedback signal. Upon detecting the exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal, which is used as a reading light to read the chlorophyll fluorescence signal generated by the target plant. At this time, the measurement light signal falls within the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire a dark-state maximum fluorescence frame image of the target plant in the dark-state maximum fluorescence state within the true exposure window, thus achieving hard real-time synchronization between the fluorescence camera, the saturated pulse light channel (SP), and the measurement light channel (ML).

[0100] It should be noted that during the maximum fluorescence acquisition phase in the dark state, the hard real-time synchronization control unit still keeps the active light channel (AL) and the far-infrared light channel (FR) closed at all times.

[0101] In one embodiment, during the dark-state maximum fluorescence acquisition stage, the hard real-time synchronization control unit can also perform multiple hard real-time synchronization controls on the fluorescence camera, the active light channel (AL), the saturated pulse light channel (SP), the far-red light channel (FR), and the measurement light channel (ML) based on the clock cycle to acquire multiple frames of dark-state maximum fluorescence frames of the target plant.

[0102] After the fluorescence camera outputs each frame of maximum fluorescence in the dark state, the hard real-time synchronization control unit is also used to acquire the true exposure window of the fluorescence camera, the distance detection information of the light shield generated by the distance detection unit, the driving current information of the corresponding functional light source generated by each current detection unit, the light feedback information of the corresponding functional light source generated by each light output detection unit, and the operating temperature information of the corresponding functional light source generated by each temperature detection unit. Combined with each frame of maximum fluorescence in the dark state and the sampling time of each frame of maximum fluorescence in the dark state, frame-level maximum fluorescence measurement data of the target plant is generated.

[0103] That is, the frame-level maximum fluorescence measurement data in the dark state includes: one or more frames of maximum fluorescence frames in the dark state, the sampling time of each frame of maximum fluorescence frames in the dark state, and the hardware status metadata of the chlorophyll fluorescence imaging module when acquiring each frame of maximum fluorescence frames in the dark state. The hardware status metadata includes at least: the actual exposure window of the fluorescence camera when acquiring the frame of maximum fluorescence in the dark state, the pose information of the fluorescence camera, the distance detection information of the light shield, and the driving current information, light feedback information, and operating temperature information of each functional light source.

[0104] Furthermore, a preparation task is performed before the maximum fluorescence acquisition phase in the dark state. The timing of the hard real-time synchronization control unit's hard real-time synchronization control in each clock cycle is as follows: Figure 6 As shown. At time T0, the hard real-time synchronization control unit keeps the action light channel (AL), the measurement light channel (ML), and the far-infrared light channel (FR) closed, and controls the saturated pulse light channel (SP) to output a saturated pulse light signal at time T2. This saturated pulse light signal remains at a high level from time T2 to time T4, and its pulse period includes at least the time interval from time T2 to time T4. After the saturated pulse light signal illuminates the target plant for a preset time (illuminating a preset number of clock cycles), the target plant can enter the dark state of maximum fluorescence.

[0105] Once the target plant enters the dark-state maximum fluorescence state, in order to acquire the dark-state maximum fluorescence frame image, the timing sequence of the hard real-time synchronization control unit in each clock cycle is as follows: Figure 5 As shown. At time T0, the hard real-time synchronization control unit keeps the action light channel (AL), the saturated pulse light channel (SP), and the far-infrared light channel (FR) closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting the exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal from time T2 to T4, which is used as a reading light to read the chlorophyll fluorescence signal produced by the target plant. At this time, the fluorescence camera maintains the exposure state, and the measurement light signal falls into the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire the maximum fluorescence frame image in the dark state. This maximum fluorescence frame image in the dark state contains the chlorophyll fluorescence signal of the target plant in the maximum dark state. The exposure feedback signal of the fluorescence camera ends before time T5, at which point image acquisition is complete. The hard real-time synchronization control unit begins acquiring hardware status metadata of the acquired maximum fluorescence frame image in the dark state at time T5.

[0106] Step S35: Control the multi-channel functional light source to irradiate the target plant with light signals, so that the target plant enters the light adaptation state. Based on the clock cycle, control the fluorescence camera and the multi-channel functional light source to enter the light adaptation fluorescence acquisition stage in real time, acquire the light adaptation fluorescence frame image of the target plant, and at the same time obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level light adaptation fluorescence measurement data.

[0107] In one embodiment, after completing the dark-state maximum fluorescence acquisition phase of the target plant, the hard real-time synchronization control unit controls the active light channel (AL) to continuously output an active light signal to continuously irradiate the target plant. After the active light signal has irradiated the target plant for a preset time, the target plant can enter a light adaptation state. At this time, the hard real-time synchronization control unit can control the fluorescence camera and the multi-channel functional light source to enter the light adaptation fluorescence acquisition phase in hard real-time synchronization.

[0108] In this embodiment, while the active light channel (AL) continuously outputs an active light signal to illuminate the target plant, the hard real-time synchronization control unit can also control the fluorescence camera to perform an exposure operation and acquire one or more frames of light-adapted background frame images.

[0109] In one embodiment, after the target plant enters a light-adapted state, during the clock cycle, the hard real-time synchronization control unit controls the action light channel (AL) to continuously output an action light signal and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal, begins exposure, and outputs an exposure feedback signal. Upon detecting the exposure feedback signal, the hard real-time synchronization control unit synchronously controls the measurement light channel (ML) to output a measurement light signal during the continuous action of the action light signal, which is used as a reading light to read the chlorophyll fluorescence signal generated by the target plant. At this time, the measurement light signal falls within the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire a light-adapted fluorescence frame image of the target plant in a light-adapted state within the true exposure window, thus achieving hard real-time synchronization between the fluorescence camera, the action light channel (AL), and the measurement light channel (ML).

[0110] It should be noted that during the light-adaptive fluorescence acquisition stage, the hard real-time synchronization control unit also controls the saturated pulse light channel (SP) and the far-infrared light channel (FR) to remain closed at all times.

[0111] In one embodiment, during the light-adapted fluorescence acquisition stage, the hard real-time synchronization control unit can also perform multiple hard real-time synchronization controls on the fluorescence camera, the active light channel (AL), the saturated pulse light channel (SP), the far-red light channel (FR), and the measurement light channel (ML) based on the clock cycle to acquire multiple frames of light-adapted fluorescence frame images of the target plant.

[0112] After the fluorescence camera outputs each frame of light-adapted fluorescence frame image, the hard real-time synchronization control unit is also used to acquire the true exposure window of the fluorescence camera, the distance detection information of the light shield generated by the distance detection unit, the driving current information of the corresponding functional light source generated by each current detection unit, the light feedback information of the corresponding functional light source generated by each light output detection unit, and the operating temperature information of the corresponding functional light source generated by each temperature detection unit. Combined with each frame of light-adapted fluorescence frame image and the sampling time of each frame of light-adapted fluorescence frame image, frame-level light-adapted fluorescence measurement data of the target plant is generated.

[0113] That is, the frame-level light-adapted fluorescence measurement data includes: one or more light-adapted background frame images, the sampling time of each light-adapted background frame image, one or more light-adapted fluorescence frame images, the sampling time of each light-adapted fluorescence frame image, and hardware status metadata of the chlorophyll fluorescence imaging module when acquiring each light-adapted fluorescence frame image. The hardware status metadata includes at least: the actual exposure window of the fluorescence camera when acquiring the light-adapted fluorescence frame image, the pose information of the fluorescence camera, the distance detection information of the light shield, and the driving current information, light feedback information, and operating temperature information of each functional light source.

[0114] Furthermore, preparation tasks are performed before the light-adaptive fluorescence acquisition stage. The timing of the hard real-time synchronization control unit's hard real-time synchronization control in each clock cycle is as follows: Figure 7 As shown. At time T0, the hard real-time synchronization control unit controls the active light channel (AL) to continuously output an active light signal, controls the saturated pulse light channel (SP), the measurement light channel (ML), and the far-infrared light channel (FR) to remain closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1 to acquire the light-adapted background frame image. After the active light signal illuminates the target plant for a preset time (illuminating a preset number of clock cycles), the target plant can enter the light-adapted state.

[0115] Once the target plant enters the light-adapted state, in order to acquire the light-adapted fluorescence frame image, the timing sequence of the hard real-time synchronization control unit within each clock cycle is as follows: Figure 8As shown. At time T0, the hard real-time synchronization control unit controls the action light channel (AL) to continuously output the action light signal, controls the saturated pulse light channel (SP) and the far-infrared light channel (FR) to remain closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting the exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal from time T2 to T4, which is used as a reading light to read the chlorophyll fluorescence signal produced by the target plant. During this period, the action light signal is continuously applied, the fluorescence camera remains in exposure mode, and the measurement light signal falls into the current true exposure window of the fluorescence camera. The fluorescence camera acquires the light-adapted fluorescence frame image. This light-adapted fluorescence frame image contains the chlorophyll fluorescence signal of the target plant under light-adapted conditions. The exposure feedback signal of the fluorescence camera ends before time T5, at which point image acquisition is complete. The hard real-time synchronization control unit begins acquiring hardware status metadata of the acquired light-adapted fluorescence frame image at time T5.

[0116] Step S36: Control the multi-channel functional light source to simultaneously irradiate the target plant with saturated pulse light signal and action light signal, so that the target plant enters the maximum fluorescence state. Based on the clock cycle, control the fluorescence camera and the multi-channel functional light source to enter the maximum fluorescence acquisition stage, acquire the maximum fluorescence frame image of the target plant, and at the same time obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level maximum fluorescence measurement data.

[0117] In one embodiment, after completing the photoadaptation fluorescence acquisition phase of the target plant, the hard real-time synchronization control unit controls the active light channel (AL) to continuously output an active light signal and controls the saturated pulse light channel (SP) to output periodic saturated pulse light signals to continuously irradiate the target plant. After the active light signal and the saturated pulse light signal have irradiated the target plant for a preset time, the target plant can enter the maximum fluorescence state. At this time, the hard real-time synchronization control unit can synchronously control the fluorescence camera and the multi-channel functional light source to enter the maximum fluorescence acquisition phase.

[0118] In this embodiment, when the active light channel (AL) continuously outputs an active light signal and the saturated pulse light channel (SP) outputs a saturated pulse light signal to irradiate the target plant, the hard real-time synchronization control unit can also control the fluorescence camera to perform an exposure operation and acquire one or more frames of the maximum background frame image.

[0119] In one embodiment, after the target plant enters its maximum photoluminescence state, within the clock cycle, the hard real-time synchronization control unit controls the active light channel (AL) to continuously output an active light signal and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal by starting exposure and outputting an exposure feedback signal. Upon detecting the exposure feedback signal, the hard real-time synchronization control unit synchronously controls the saturated pulse light channel (SP) to output a saturated pulse light signal and the measurement light channel (ML) to output a measurement light signal, using the measurement light signal as a reading light to read the chlorophyll fluorescence signal produced by the target plant. At this time, the measurement light signal falls within the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire a maximum photoluminescence frame image of the target plant in its maximum photoluminescence state within the true exposure window, thus achieving hard real-time synchronization between the fluorescence camera and the active light channel (AL), the saturated pulse light channel (SP), and the measurement light channel (ML).

[0120] It should be noted that during the maximum fluorescence acquisition phase, the hard real-time synchronization control unit also controls the far-infrared (FR) channel to remain closed at all times.

[0121] In one embodiment, during the maximum fluorescence acquisition stage, the hard real-time synchronization control unit can also perform multiple hard real-time synchronization controls on the fluorescence camera, the active light channel (AL), the saturated pulse light channel (SP), the far-red light channel (FR), and the measurement light channel (ML) based on the clock cycle to acquire multiple frames of maximum fluorescence frames of the target plant.

[0122] After the fluorescence camera outputs the maximum fluorescence frame images of each frame, the hard real-time synchronization control unit is also used to acquire the true exposure window of the fluorescence camera, the distance detection information of the light shield generated by the distance detection unit, the driving current information of the corresponding functional light source generated by each current detection unit, the light feedback information of the corresponding functional light source generated by each light output detection unit, and the operating temperature information of the corresponding functional light source generated by each temperature detection unit. Combined with the maximum fluorescence frame images of each frame and the sampling time of each maximum fluorescence frame image, frame-level maximum fluorescence measurement data of the target plant is generated.

[0123] That is, the frame-level maximum fluorescence measurement data includes: one or more frames of maximum background image, the sampling time of each frame of maximum background image, one or more frames of maximum fluorescence image, the sampling time of each frame of maximum fluorescence image, and the hardware status metadata of the chlorophyll fluorescence imaging module when acquiring each frame of maximum fluorescence image. The hardware status metadata includes at least: the actual exposure window of the fluorescence camera when acquiring the frame of maximum fluorescence image, the pose information of the fluorescence camera, the distance detection information of the light shield, and the driving current information, light feedback information, and operating temperature information of each functional light source.

[0124] Furthermore, a preparation task is performed before the maximum fluorescence acquisition phase. The timing of the hard real-time synchronization control unit's hard real-time synchronization control within each clock cycle is as follows: Figure 9 As shown. At time T0, the hard real-time synchronization control unit controls the action light channel (AL) to continuously output the action light signal, controls the measurement light channel (ML) and the far-infrared light channel (FR) to remain closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting the exposure feedback signal, the hard real-time synchronization control unit controls the saturation pulse light channel (SP) to output a saturation pulse light signal at time T2. The saturation pulse light signal remains high from time T2 to time T4, and its pulse period includes at least the time interval from time T2 to time T4 and falls within the clock cycle. At this time, the saturation pulse light signal falls into the current true exposure window of the fluorescence camera, and the fluorescence camera acquires the maximum background frame image of the photodynamic state. After the action light signal and the saturation pulse light signal illuminate the target plant for a preset time (illuminating a preset number of clock cycles), the target plant can be brought into the maximum fluorescence state.

[0125] Once the target plant enters its maximum photofluorescence state, the timing sequence of the hard real-time synchronization control unit within each clock cycle for acquiring the maximum photofluorescence frame image is as follows: Figure 10As shown. At time T0, the hard real-time synchronization control unit controls the active light channel (AL) to continuously output an active light signal, controls the far-infrared light channel (FR) to close, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting the exposure feedback signal, the hard real-time synchronization control unit controls the saturated pulse light channel to output a saturated pulse light signal from time T2 to T4, and synchronously controls the measurement light channel (ML) to output a measurement light signal from time T2 to T4, so as to use the measurement light signal as a reading light to read the chlorophyll fluorescence signal produced by the target plant. At this time, the active light signal and the saturated pulse light signal are in action, the fluorescence camera maintains the exposure state, and the measurement light signal falls within the current true exposure window of the fluorescence camera. The fluorescence camera acquires the maximum fluorescence frame image under the maximum fluorescence state. This maximum fluorescence frame image contains the chlorophyll fluorescence signal of the target plant under the maximum fluorescence state. The exposure feedback signal of the fluorescence camera ends before time T5, at which point image acquisition is completed. The hard real-time synchronization control unit begins to acquire hardware status metadata of the acquired frame of the maximum fluorescence frame at time T5.

[0126] It should be noted that, in this embodiment, the pulse period of the saturated pulse light signal includes at least the time interval from T2 to T4, and the saturated pulse light signal remains at a high level from T2 to T4, thereby ensuring that the saturated pulse light signal is exactly in action during the output of the measured light signal.

[0127] Step S37: Control the multi-channel functional light source to irradiate the target plant with far-red light signals, causing the target plant to enter the minimum fluorescence state. Based on the clock cycle, control the fluorescence camera and the multi-channel functional light source to enter the minimum fluorescence acquisition stage, acquire the minimum fluorescence frame image of the target plant, and simultaneously obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level minimum fluorescence measurement data.

[0128] In one embodiment, after completing the maximum fluorescence acquisition phase of the target plant, the hard real-time synchronization control unit controls the far-infrared channel (FR) to output a medium-intensity short-pulse far-infrared light signal, which is a periodic square wave pulse signal. After the far-infrared light signal illuminates the target plant for a preset time, the target plant can enter the photofluorescence state. At this time, the hard real-time synchronization control unit can synchronously control the fluorescence camera and the multi-channel functional light source to enter the minimum fluorescence acquisition phase.

[0129] In one embodiment, after the target plant enters the minimum photoluminescence state, within the clock cycle, the hard real-time synchronization control unit controls the far-infrared (FR) channel to close and synchronously sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal by starting exposure and outputting an exposure feedback signal. Upon detecting the exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal, which is used as a reading light to read the chlorophyll fluorescence signal produced by the target plant. At this time, the measurement light signal falls within the current true exposure window of the fluorescence camera, allowing the fluorescence camera to acquire a minimum photoluminescence frame image of the target plant in the minimum photoluminescence state within the true exposure window, thus achieving hard real-time synchronization between the fluorescence camera, the far-infrared (FR) channel, and the measurement light channel (ML).

[0130] It should be noted that during the minimum fluorescence acquisition stage, the hard real-time synchronization control unit also controls the active light channel (AL) and the saturated pulse light channel (SP) to remain closed at all times.

[0131] In one embodiment, during the minimum fluorescence acquisition stage, the hard real-time synchronization control unit can also perform multiple hard real-time synchronization controls on the fluorescence camera, the active light channel (AL), the saturated pulse light channel (SP), the far-red light channel (FR), and the measurement light channel (ML) based on the clock cycle to acquire multiple frames of minimum fluorescence frames of the target plant.

[0132] After the fluorescence camera outputs each frame of minimum fluorescence frame images, the hard real-time synchronization control unit is also used to acquire the true exposure window of the fluorescence camera, the distance detection information of the light shield generated by the distance detection unit, the driving current information of the corresponding functional light source generated by each current detection unit, the light feedback information of the corresponding functional light source generated by each light output detection unit, and the operating temperature information of the corresponding functional light source generated by each temperature detection unit. Combined with each frame of minimum fluorescence frame images and the sampling time of each frame of minimum fluorescence frame images, frame-level minimum fluorescence measurement data of the target plant is generated.

[0133] That is, the frame-level minimum fluorescence measurement data includes: one or more minimum fluorescence frame images, the sampling time of each minimum fluorescence frame image, and hardware status metadata of the chlorophyll fluorescence imaging module when acquiring each minimum fluorescence frame image. The hardware status metadata includes at least: the actual exposure window of the fluorescence camera when acquiring the minimum fluorescence frame image, the pose information of the fluorescence camera, the distance detection information of the light shield, and the driving current information, light feedback information, and operating temperature information of each functional light source.

[0134] Furthermore, a preparation task is performed before the minimum fluorescence acquisition stage. The timing of the hard real-time synchronization control unit in each clock cycle is as follows: Figure 11 As shown. At time T0, the hard real-time synchronization control unit keeps the action light channel (AL), the measurement light channel (ML), and the saturated pulse light channel (SP) closed, and controls the far-infrared light channel (FR) to output a far-infrared light signal at time T2. The pulse period of this far-infrared light signal falls within the clock cycle. After the far-infrared light signal illuminates the target plant for a preset time (an preset number of clock cycles), the target plant can enter the minimum photoluminescence state.

[0135] Once the target plant enters the minimum fluorescence state, the timing of the hard real-time synchronization control unit within each clock cycle for acquiring the minimum fluorescence frame image is as follows: Figure 5 As shown. At time T0, the hard real-time synchronization control unit keeps the action light channel (AL), the saturated pulse light channel (SP), and the far-infrared light channel (FR) closed, and sends a camera trigger signal to the fluorescence camera. The fluorescence camera responds to the camera trigger signal and begins exposure, outputting an exposure feedback signal at time T1. After detecting the exposure feedback signal, the hard real-time synchronization control unit controls the measurement light channel (ML) to output a measurement light signal from time T2 to T4, which is used as a reading light to read the chlorophyll fluorescence signal produced by the target plant. At this time, the far-infrared light signal is in the blanking period, the fluorescence camera remains in the exposure state, and the measurement light signal falls into the current true exposure window of the fluorescence camera. The fluorescence camera acquires the minimum fluorescence frame image. The minimum fluorescence frame image contains the chlorophyll fluorescence signal of the target plant under the minimum fluorescence state. The exposure feedback signal of the fluorescence camera ends before time T5, at which point image acquisition is completed. The hard real-time synchronization control unit begins to acquire hardware status metadata of the acquired minimum fluorescence frame image at time T5.

[0136] In each fluorescence acquisition stage, this application uses only the measurement light signal as the reading light, so that each acquired fluorescence frame image has consistent reading conditions, thereby ensuring that each chlorophyll fluorescence parameter image generated has consistent reading conditions and making each chlorophyll fluorescence parameter image comparable.

[0137] Furthermore, this application, through the hard real-time synchronization control logic of the hard real-time synchronization control unit, confines camera triggering, exposure feedback, functional light output, measurement light output, and hardware status metadata generation within a unified hardware timing sequence. This ensures that the measurement light signal accurately falls into the true exposure window of the fluorescence camera at each fluorescence acquisition stage, while simultaneously preventing the leakage of the action light signal, saturation pulse light signal, and far-infrared light signal into the fluorescence detection channel. This improves the accuracy and reliability of the acquired multi-frame fluorescence images, further enhancing the accuracy of the final generated chlorophyll fluorescence parameter maps.

[0138] Step S38: Generate multi-state frame-level fluorescence measurement data of the target plant based on the frame-level fluorescence background data, the frame-level dark-adapted fluorescence measurement data, the frame-level dark-state maximum fluorescence measurement data, the frame-level light-adapted fluorescence measurement data, the frame-level light-state maximum fluorescence measurement data, and the frame-level light-state minimum fluorescence measurement data.

[0139] Specifically, the multi-state frame-level fluorescence measurement data includes at least: frame-level fluorescence background data, frame-level dark-adapted fluorescence measurement data, frame-level dark-state maximum fluorescence measurement data, frame-level light-adapted fluorescence measurement data, frame-level light-state maximum fluorescence measurement data, and frame-level light-state minimum fluorescence measurement data.

[0140] In this embodiment, the present application binds each fluorescence frame image to the hardware status metadata of the chlorophyll fluorescence imaging module when acquiring that fluorescence frame image. The hardware status metadata accurately reflects the working status of the fluorescence camera and the working status of the multi-channel functional light source when acquiring that fluorescence frame image. By binding with the hardware status metadata, the acquisition conditions of each fluorescence frame image can be traced, facilitating the location of abnormal fluorescence frame images. This makes it easier to distinguish the true physiological changes of the target plant and locate abnormalities in the fluorescence acquisition link. Furthermore, it ensures the consistency of the acquisition conditions for each fluorescence image, improving the accuracy and reliability of the fluorescence frame images, thereby improving the accuracy and reliability of the final generated chlorophyll fluorescence parameter map.

[0141] In one embodiment, the chlorophyll fluorescence detection and control module further includes a frame image quality control unit. The frame image quality control unit is connected to both the chlorophyll fluorescence imaging module and the hard real-time synchronization control unit. Specifically, it is connected to the fluorescence camera, the light source driving unit of each functional light source channel, and the hard real-time synchronization control unit. In each fluorescence acquisition stage, based on preset fluorescence frame image quality control conditions, it marks each fluorescence frame image as reliable, low-reliability, or invalid.

[0142] The quality control conditions for the fluorescence frame image include at least the following: whether the fluorescence camera drops frames; whether the fluorescence frame image is overexposed; whether the fluorescence frame image is underexposed; whether the background of the fluorescence frame image is too high; whether the area of ​​interest in the fluorescence frame image is insufficient; whether the outline of the target plant in the fluorescence frame image is clear; whether the saturated pulse light signal is sufficient, whether the working light signal is stable, whether the non-working light signal is leaked, and whether the functional light source is overheated when acquiring the fluorescence frame image.

[0143] In each fluorescence acquisition stage, the hard real-time synchronization control unit obtains the corresponding frame-level fluorescence measurement data and sends it to the frame image quality control unit. The frame image quality control unit determines whether each fluorescence frame image in the frame-level fluorescence measurement data meets the fluorescence frame image quality control conditions. Based on the number of fluorescence frame images that do not meet the conditions and the deviation range, the fluorescence frame image is marked as reliable, low reliable, or invalid for subsequent inspection planning and tracing of fluorescence frame image anomalies.

[0144] Furthermore, the chlorophyll fluorescence imaging module sends the labeled multi-state frame-level fluorescence measurement data to the chlorophyll fluorescence data processing module.

[0145] Step S4: Control the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0146] In one embodiment, the chlorophyll fluorescence data processing module generates chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data, including the following steps: Figure 12 As shown.

[0147] Step S41: Perform image correction on each fluorescence frame image in the multi-state frame-level fluorescence measurement data to obtain multiple corrected fluorescence frame images.

[0148] First, the chlorophyll fluorescence data processing module performs dark field subtraction on the fluorescence frame image based on the fluorescence background frame image. This subtracts the dark field response formed by the fluorescence camera under conditions without target light signal from the fluorescence frame image, thereby obtaining a dark field-corrected fluorescence frame image. This reduces interference from supplemental lighting in the plant factory and backgrounds such as cultivation racks, cultivation troughs, water surfaces, and water droplets.

[0149] Subsequently, the chlorophyll fluorescence data processing module performs bad pixel correction on the fluorescence frame image after dark field subtraction to identify and correct the positions of pixels with abnormal responses in the fluorescence camera.

[0150] Secondly, the chlorophyll fluorescence data processing module performs flat field correction on the fluorescence frame image after bad pixel correction to compensate for the spatial differences caused by different pixel responses of the fluorescence camera and uneven illumination distribution.

[0151] Furthermore, the chlorophyll fluorescence data processing module performs background leakage correction on the flat-field calibrated fluorescence frame image to reduce the background components formed after supplemental lighting in the plant factory, ambient reflected light, and non-reading function light (such as action light signal, saturated pulse light signal, or far-red light signal) enter the fluorescence detection channel.

[0152] Step S42: Select a reliable corrected fluorescence frame image from each fluorescence acquisition stage as the key fluorescence frame image, and perform image registration on each key fluorescence frame image.

[0153] First, the chlorophyll fluorescence data processing module selects a reliable corrected fluorescence frame image from each fluorescence acquisition stage as the key fluorescence frame image. This further ensures the quality of the key fluorescence frame images involved in generating the chlorophyll fluorescence parameter maps, guaranteeing the accuracy and reliability of each chlorophyll fluorescence parameter map. It should be noted that if a key fluorescence frame image for a certain fluorescence acquisition stage is not obtained, the corresponding target detection plant can be added to the plant factory's subsequent inspection plan, such as adding it to a key location sampling plan, to achieve retesting.

[0154] Thus, each fluorescence acquisition stage yields a key fluorescence frame image. Specifically, the dark-adapted fluorescence acquisition stage yields a dark-adapted key fluorescence frame image; the dark-state maximum fluorescence acquisition stage yields a dark-state maximum key fluorescence frame image; the light-adapted fluorescence acquisition stage yields a light-adapted key fluorescence frame image; the light-state maximum fluorescence acquisition stage yields a light-state maximum key fluorescence frame image; and the light-state minimum fluorescence acquisition stage yields a light-state minimum key fluorescence frame image.

[0155] Subsequently, the chlorophyll fluorescence data processing module selects one key fluorescence frame image as a reference image and uses the other key fluorescence frame images as images to be registered. Each image to be registered is then registered with the reference image, establishing a spatial correspondence between the positions of the same leaf or the same local canopy position in each key fluorescence frame image. This compensates for image position shifts caused by the movement of the target plant leaves, changes in the state of the moving platform, changes in the end-effector posture of the mechanical actuator, or changes in the working distance of the chlorophyll fluorescence imaging module, ensuring that the multiple key fluorescence frame images involved in the chlorophyll fluorescence parameter calculation correspond to each other in pixel space.

[0156] Step S43: Perform image segmentation on each key fluorescence frame image to obtain one or more leaf regions of interest in each key fluorescence frame image, and remove the strongly reflective areas and out-of-focus areas to obtain one or more effective leaf regions of interest in each key fluorescence frame image.

[0157] Specifically, the chlorophyll fluorescence data processing module segments the region of interest (ROI) of the leaf from the key fluorescence frame image to obtain one or more leaf ROIs corresponding to the leaf or local canopy of the target plant, so as to distinguish the leaf area of ​​the target plant from the background area.

[0158] The chlorophyll fluorescence data processing module further identifies and removes strongly reflective and out-of-focus areas within the leaf's region of interest (ROI). Strongly reflective areas are removed by marking abnormally bright areas caused by leaf surface reflection or environmental reflection as invalid regions, preventing them from participating in subsequent chlorophyll fluorescence parameter extraction and photosynthetic physiological index calculations. Out-of-focus areas are removed by marking areas that do not meet the imaging sharpness requirements as invalid regions, also preventing them from participating in subsequent chlorophyll fluorescence parameter extraction and photosynthetic physiological index calculations. The remaining ROI after removing strongly reflective and out-of-focus areas constitutes the valid ROI for chlorophyll fluorescence parameter extraction and photosynthetic physiological index calculations.

[0159] Step S44: Extract the pixel values ​​of each effective leaf region of interest in each key fluorescence frame image and generate multiple chlorophyll fluorescence parameter maps of the target plant.

[0160] In one embodiment, the chlorophyll fluorescence data processing module extracts the pixel values ​​of one or more effective leaf regions of interest within the key fluorescence frame image, and generates a chlorophyll fluorescence parameter map of the target plant at the corresponding fluorescence acquisition stage based on the extracted pixel positions and pixel values.

[0161] Specifically, the chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest in the dark-adapted key fluorescence frame image, and determines each extracted pixel value as the dark-adapted fluorescence signal value of the corresponding pixel position. Based on each dark-adapted fluorescence signal value, a dark-adapted fluorescence parameter map of the target plant is generated.

[0162] The chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest in the dark-state maximum fluorescence frame image, and uses each extracted pixel value as the dark-state maximum fluorescence signal value of the corresponding pixel position. Based on each dark-state maximum fluorescence signal value, a dark-state maximum fluorescence parameter map of the target plant is generated.

[0163] The chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest within the key fluorescence frame image for light adaptation, and corrects the extracted pixel values ​​based on each light adaptation background frame image to obtain the light adaptation fluorescence signal value at each pixel location, thereby generating a light adaptation fluorescence parameter map of the target plant. In one embodiment, a light adaptation background frame image whose clarity meets preset conditions can be selected as the key background frame image for light adaptation, and the pixel values ​​at each pixel location can be extracted. A difference operation is then performed on the pixel values ​​extracted from the key fluorescence frame image for light adaptation, and the pixel differences at each pixel location after the difference operation are used as the light adaptation fluorescence signal value at the corresponding pixel location. In another embodiment, the pixel values ​​in each frame of the light adaptation background frame image can be averaged first to calculate the average pixel value at each pixel location. A difference operation is then performed on the pixel values ​​extracted from the key fluorescence frame image for light adaptation based on the average pixel value, and the pixel differences at each pixel location after the difference operation are used as the light adaptation fluorescence signal value at the corresponding pixel location.

[0164] The chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest within the maximum photochromic key fluorescence frame image, and corrects the extracted pixel values ​​based on each maximum photochromic background frame image to obtain the maximum photochromic fluorescence signal value at each pixel location, thereby generating a maximum photochromic fluorescence parameter map of the target plant. In one embodiment, a maximum photochromic background frame image with a resolution meeting a preset condition can be selected as the maximum photochromic key background frame image, and the pixel values ​​at each pixel location can be extracted. A difference operation is then performed on the pixel values ​​extracted from the maximum photochromic key fluorescence frame image, and the pixel differences at each pixel location after the difference operation are used as the maximum photochromic fluorescence signal value at the corresponding pixel location. In another embodiment, the pixel values ​​in each maximum photochromic background frame image can first be averaged to calculate the average pixel value at each pixel location. Then, a difference operation is performed on the pixel values ​​extracted from the maximum photochromic key fluorescence frame image based on the average pixel value, and the pixel differences at each pixel location after the difference operation are used as the maximum photochromic fluorescence signal value at the corresponding pixel location.

[0165] The chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest in the minimum fluorescence frame image and uses each extracted pixel value as the minimum fluorescence signal value of the corresponding pixel position. Based on each minimum fluorescence signal value, a minimum fluorescence parameter map of the target plant is generated.

[0166] In one embodiment, the chlorophyll fluorescence data processing module can also perform pixel-by-pixel chlorophyll fluorescence parameter calculation based on the generated dark-adapted fluorescence parameter map, the dark-state maximum fluorescence parameter map, the light-adapted fluorescence parameter map, the light-state maximum fluorescence parameter map, and the light-state minimum fluorescence parameter map. This allows for the calculation of multiple photosynthetic physiological indicators at each pixel location of the target plant, generating the target plant's maximum photochemical quantum efficiency parameter map, actual photochemical quantum efficiency parameter map, non-photochemical quenching parameter map, maximum photochemical quantum efficiency parameter map under light adaptation, compartment model photochemical quenching parameter map, and lake model photochemical quenching parameter map.

[0167] Specifically, based on the dark-adapted fluorescence parameter map and the dark-state maximum fluorescence parameter map, the dark-adapted fluorescence signal value and the dark-state maximum fluorescence signal value at each pixel location are obtained, and the maximum photochemical quantum efficiency at each pixel location is calculated to generate the maximum photochemical quantum efficiency parameter map of the target plant.

[0168] The formula for calculating the maximum photochemical quantum efficiency is as follows:

[0169] ;Formula (1)

[0170] in, The maximum photochemical quantum efficiency at a pixel location; This represents the dark-adapted fluorescence signal value at that pixel location; This represents the maximum fluorescence signal value in the dark state at that pixel location.

[0171] Based on the light-adapted fluorescence parameter map and the maximum fluorescence parameter map, the light-adapted fluorescence signal value and the maximum fluorescence signal value of each pixel position are obtained, and the actual photochemical quantum efficiency of each pixel position is calculated to generate the actual photochemical quantum efficiency parameter map of the target plant.

[0172] The formula for calculating the actual photochemical quantum efficiency is as follows:

[0173] ;Formula (2)

[0174] in, This represents the actual photochemical quantum efficiency at a single pixel location. This represents the light-adaptive fluorescence signal value at that pixel location; This represents the maximum fluorescence signal value at that pixel location.

[0175] Based on the maximum fluorescence parameter map in the dark state and the maximum fluorescence parameter map in the light state, the maximum fluorescence signal value in the dark state and the maximum fluorescence signal value in the light state at each pixel location are obtained, and the non-photochemical quenching parameter at each pixel location is calculated to generate a non-photochemical quenching parameter map of the target plant.

[0176] The formula for calculating the non-photochemical quenching parameter is as follows:

[0177] ;Formula (3)

[0178] in, The non-photochemical quenching parameter for a pixel location; This represents the maximum fluorescence signal value in the dark state at that pixel location; This represents the maximum fluorescence signal value at that pixel location.

[0179] Based on the maximum and minimum fluorescence parameters of the photostate, the maximum and minimum fluorescence signal values ​​of the photostate at each pixel location are obtained, and the maximum photochemical quantum efficiency under light adaptation at each pixel location is calculated to generate a parameter map of the maximum photochemical quantum efficiency under light adaptation for the target plant.

[0180] The formula for calculating the maximum photochemical quantum efficiency under light adaptation is as follows:

[0181] ;Formula (4)

[0182] in, The maximum photochemical quantum efficiency under light adaptation at a single pixel location; This represents the maximum fluorescence signal value of the optical state at that pixel location; This represents the minimum fluorescence signal value at the pixel location.

[0183] Based on the light-adapted fluorescence parameter map, the maximum fluorescence parameter map, and the minimum fluorescence parameter map, the light-adapted fluorescence signal value, the maximum fluorescence signal value, and the minimum fluorescence signal value at each pixel location are obtained, and the cell model photochemical quenching coefficient at each pixel location is calculated to generate the cell model photochemical quenching parameter map of the target plant.

[0184] The formula for calculating the photochemical quenching coefficient of the compartment model is as follows:

[0185] ;Formula (5)

[0186] in, The photochemical quenching coefficient of the compartment model at a pixel location; This represents the light-adaptive fluorescence signal value at that pixel location; This represents the maximum fluorescence signal value of the optical state at that pixel location; This represents the minimum fluorescence signal value at the pixel location.

[0187] Based on the light-adapted fluorescence parameter map, the maximum fluorescence parameter map, and the minimum fluorescence parameter map, the light-adapted fluorescence signal value, the maximum fluorescence signal value, and the minimum fluorescence signal value at each pixel location are obtained, and the lake model photochemical quenching coefficient at each pixel location is calculated to generate the lake model photochemical quenching parameter map of the target plant.

[0188] The formula for calculating the photochemical quenching coefficient of the lake model is as follows:

[0189] ;Formula (6)

[0190] in, The photochemical quenching coefficient of the lake model at a pixel location; This represents the light-adaptive fluorescence signal value at that pixel location; This represents the maximum fluorescence signal value of the optical state at that pixel location; This represents the minimum fluorescence signal value at the pixel location.

[0191] Thus, multiple chlorophyll fluorescence parameter maps are obtained, including the dark-adapted fluorescence parameter map, the dark-state maximum fluorescence parameter map, the light-adapted fluorescence parameter map, the light-state maximum fluorescence parameter map, the light-state minimum fluorescence parameter map, the maximum photochemical quantum efficiency parameter map, the actual photochemical quantum efficiency parameter map, the non-photochemical quenching parameter map, the light-adapted maximum photochemical quantum efficiency parameter map, the compartment model photochemical quenching parameter map, and the lake model photochemical quenching parameter map. These maps are used to characterize different photosynthetic physiological indicators of the target plant and to assess the photosynthetic state of the target plant.

[0192] In one embodiment, the chlorophyll fluorescence detection control module can also upload the generated chlorophyll fluorescence parameter maps to the cloud via a communication module for subsequent verification and optimization of the in-situ chlorophyll fluorescence detection system in the plant factory, specifically providing a data foundation for it.

[0193] In one embodiment, after the chlorophyll fluorescence detection control module controls the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module to complete the chlorophyll fluorescence detection of the current target plant, it continues to select another plant in the target detection area corresponding to the current target detection station as the target plant. It then controls the mechanical actuator to move the chlorophyll fluorescence imaging module closer to the target plant, so that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant. Furthermore, it controls the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant and controls the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant.

[0194] After the chlorophyll fluorescence detection control module controls the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module to complete the chlorophyll fluorescence detection of all plants in the target detection area corresponding to the current target detection station, it continues to determine the next target detection station according to the preset inspection route, and controls the mobile platform to move along the inspection route to the next target detection station and stop, repeating steps S1 to S4 to perform chlorophyll fluorescence detection on all plants in the target detection area corresponding to the target detection station.

[0195] Therefore, this application realizes a complete closed loop of mobile image acquisition, quality control, chlorophyll fluorescence detection, and frame-level metadata traceability through the plant factory in-situ chlorophyll fluorescence detection system, thereby enabling the monitoring of the photosynthetic status of plants during the automatic inspection of the plant factory, and is adaptable to automatic inspection scenarios with multi-layer shelves, narrow passages, and multiple locations in the plant factory.

[0196] It should be understood that the module division in the system embodiments of this application is illustrative and only represents a logical functional division. In actual implementation, there may be other division methods. Furthermore, the functional modules in the various embodiments of this application can be integrated into a single processor or functional module, exist as separate physical entities, or be divided into more functional modules. The integrated modules or units described above can be implemented in hardware or as software functional modules.

[0197] This application also provides a method for in-situ chlorophyll fluorescence detection and control in a plant factory. The method described in this embodiment is applied to the chlorophyll fluorescence detection and control module of an in-situ chlorophyll fluorescence detection system for a plant factory. The in-situ chlorophyll fluorescence detection system for a plant factory is consistent with the systems described in the above embodiments, and will not be repeated here for simplicity.

[0198] like Figure 3 As shown, the in-situ chlorophyll fluorescence detection and control method in the plant factory mainly includes the following steps.

[0199] Step S1: Control the mobile platform to move along the preset inspection route within the plant factory and stop at the target inspection station.

[0200] Step S2: Control the mechanical actuator to move the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant.

[0201] Step S3: Control the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module.

[0202] Step S4: Control the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0203] It should be understood that the in-situ chlorophyll fluorescence detection and control method for plant factories described in this application belongs to the same inventive concept as the in-situ chlorophyll fluorescence detection systems for plant factories provided in the above system embodiments, and will not be described again here for the sake of brevity.

[0204] like Figure 13 The diagram illustrates the structure of an in-situ chlorophyll fluorescence detection device for a plant factory, as described in this embodiment. This device is connected to an external plant factory inspection robot, allowing it to be applied to existing plant factory inspection robots. The device primarily comprises a chlorophyll fluorescence imaging module, a chlorophyll fluorescence data processing module, and a chlorophyll fluorescence detection control module.

[0205] The chlorophyll fluorescence imaging module is connected to the plant factory inspection robot and is detachably mounted on the mechanical actuator of the plant factory inspection robot, which is mounted on the mobile platform of the plant factory inspection robot.

[0206] The chlorophyll fluorescence data processing module is connected to the chlorophyll fluorescence imaging module.

[0207] The chlorophyll fluorescence detection and control module is connected to the chlorophyll fluorescence imaging module, the chlorophyll fluorescence data processing module, and the mobile platform and mechanical actuator of the plant factory inspection robot, and is configured to perform the following steps.

[0208] ① Control the mobile platform to move along the preset inspection route within the plant factory and stop at the target inspection station.

[0209] ② Control the mechanical actuator to drive the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module maintains a preset working distance and measurement posture with the target plant.

[0210] ③ Control the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module.

[0211] ④ Control the chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

[0212] It should be understood that the in-situ chlorophyll fluorescence detection device for plant factories described in this application belongs to the same inventive concept as the various in-situ chlorophyll fluorescence detection systems for plant factories provided in the above system embodiments, and will not be described again here for the sake of brevity.

[0213] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0214] In summary, this application provides an in-situ chlorophyll fluorescence detection system, control method, and device for plant factories. The system uses a chlorophyll fluorescence detection control module to control a mobile platform to move along an inspection route to the target detection station and stop. It also controls a mechanical actuator to bring the chlorophyll fluorescence imaging module closer to the target plant, thereby controlling the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant. This obtains multi-state frame-level fluorescence measurement data of the target plant, which is then sent to a chlorophyll fluorescence data processing module to generate multiple chlorophyll fluorescence parameter maps of the target plant. This enables the monitoring of the photosynthetic state of plants during automated inspections in plant factories, solving the technical problem of existing plant factory inspection systems that struggle to accurately, reliably, and repeatedly assess the photosynthetic state of plants.

[0215] Therefore, this application effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0216] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. An in-situ chlorophyll fluorescence detection system for plant factories, characterized in that, include: A mobile platform; the mobile platform is equipped with a mechanical actuator, and the end of the mechanical actuator is equipped with a chlorophyll fluorescence imaging module; A chlorophyll fluorescence data processing module is connected to the chlorophyll fluorescence imaging module; The chlorophyll fluorescence detection and control module, connected to the mobile platform, the mechanical actuator, the chlorophyll fluorescence imaging module, and the chlorophyll fluorescence data processing module, is configured as follows: The mobile platform is controlled to move along a preset inspection route within the plant factory and stop at the target inspection station; The mechanical actuator is controlled to move the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module and the target plant maintain a preset working distance and measurement posture; The chlorophyll fluorescence imaging module is controlled to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module. The chlorophyll fluorescence data processing module is controlled to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

2. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 1, characterized in that, The chlorophyll fluorescence imaging module includes at least: A fluorescence camera is used to acquire multiple fluorescence frames of the target plant under different physiological states within a real exposure window in response to a camera trigger signal. A multi-channel functional light source includes at least: a measurement light channel, an action light channel, a saturated pulse light channel, and a far-infrared light channel; each functional light source channel of the multi-channel functional light source is arranged around the imaging field of view of the fluorescence camera, such that the illumination area of ​​each functional light source channel coincides or substantially coincides with the imaging area of ​​the fluorescence camera; each functional light source channel includes at least: a light source driving unit, a functional light source, a current detection unit, a light output detection unit, and a temperature detection unit; A light shield is disposed on the outside of the fluorescence camera, facing the imaging area of ​​the fluorescence camera and the light-emitting area of ​​the multi-channel functional light source, for forming a local light-shielding space above the target plant; a distance detection unit is disposed on the light shield.

3. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 2, characterized in that, The chlorophyll fluorescence detection and control module is equipped with: A safety interlock unit, connected to the mechanical actuator and the chlorophyll fluorescence imaging module, is used to control the start of the chlorophyll fluorescence imaging module and determine whether the chlorophyll fluorescence imaging module meets the preset chlorophyll fluorescence detection conditions. If the chlorophyll fluorescence imaging module does not meet the chlorophyll fluorescence detection conditions, the working state of the mechanical actuator or the chlorophyll fluorescence imaging module is adjusted until the chlorophyll fluorescence imaging module meets the chlorophyll fluorescence detection conditions, allowing the chlorophyll fluorescence imaging module to start chlorophyll fluorescence imaging of the target plant. The chlorophyll fluorescence detection conditions include at least the following: whether the working status of the fluorescence camera and the multi-channel functional light source is normal; whether the light shield is properly opened; and whether the distance and relative posture between the light shield and the target plant meet the conditions for safe irradiation and effective shading.

4. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 2, characterized in that, The chlorophyll fluorescence detection and control module is equipped with a hard real-time synchronization control unit; the hard real-time synchronization control unit is connected to the chlorophyll fluorescence imaging module and is used to control the chlorophyll fluorescence imaging module to perform chlorophyll fluorescence imaging on the target plant according to a preset time sequence requirement. Specific methods include: Initialize the fluorescent camera and each functional light source channel of the multi-channel functional light source; Based on a preset clock cycle, the fluorescence camera is controlled to perform an exposure operation to acquire fluorescence background frame images of the target plant and generate frame-level fluorescence background data. Once the target plant enters the dark adaptation state, based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real time to enter the dark adaptation fluorescence acquisition stage, acquire dark adaptation fluorescence frame images of the target plant, and simultaneously obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level dark adaptation fluorescence measurement data. The multi-channel functional light source is controlled to irradiate the target plant with a saturated pulse light signal, causing the target plant to enter the dark state of maximum fluorescence. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real time to enter the dark state maximum fluorescence acquisition stage to acquire the dark state maximum fluorescence frame image of the target plant. At the same time, the hardware status metadata of the current chlorophyll fluorescence imaging module is acquired to generate frame-level dark state maximum fluorescence measurement data. The multi-channel functional light source is controlled to irradiate the target plant with light signals, causing the target plant to enter a light-adaptive state. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real time to enter the light-adaptive fluorescence acquisition stage, acquiring light-adaptive fluorescence frame images of the target plant. At the same time, the hardware status metadata of the current chlorophyll fluorescence imaging module is obtained to generate frame-level light-adaptive fluorescence measurement data. The multi-channel functional light source is controlled to simultaneously irradiate the target plant with saturated pulse light signal and action light signal, causing the target plant to enter the maximum fluorescence state. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real time to enter the maximum fluorescence acquisition stage, acquire the maximum fluorescence frame image of the target plant, and at the same time obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level maximum fluorescence measurement data. The multi-channel functional light source is controlled to irradiate the target plant with far-red light signals, causing the target plant to enter the minimum fluorescence state. Based on the clock cycle, the fluorescence camera and the multi-channel functional light source are controlled in real time to enter the minimum fluorescence acquisition stage, acquire the minimum fluorescence frame image of the target plant, and at the same time obtain the hardware status metadata of the current chlorophyll fluorescence imaging module to generate frame-level minimum fluorescence measurement data. Based on the frame-level fluorescence background data, the frame-level dark-adapted fluorescence measurement data, the frame-level dark-state maximum fluorescence measurement data, the frame-level light-adapted fluorescence measurement data, the frame-level light-state maximum fluorescence measurement data, and the frame-level light-state minimum fluorescence measurement data, multi-state frame-level fluorescence measurement data of the target plant is generated.

5. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 4, characterized in that, The hard real-time synchronization control unit controls the fluorescence camera and each functional light source channel in a hard real-time synchronization manner, including: The hard real-time synchronization control unit sends a camera trigger signal to the fluorescence camera, so that the fluorescence camera responds to the camera trigger signal to start exposure and outputs an exposure feedback signal; During the dark-adapted fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel and the far-infrared light channel to remain closed, and after detecting the exposure feedback signal, controls the measurement light channel to output the measurement light signal to induce the target plant to produce chlorophyll fluorescence signal and read the chlorophyll fluorescence signal, so that the fluorescence camera can acquire dark-adapted fluorescence frame images within the real exposure window. During the dark-state maximum fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel and the far-infrared light channel to remain closed, and after detecting the exposure feedback signal, controls the measurement light channel to output the measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, so that the fluorescence camera can acquire the dark-state maximum fluorescence frame image within the real exposure window; During the light-adaptive fluorescence acquisition stage, the hard real-time synchronization control unit controls the active light channel to continuously output the active light signal, controls the saturated pulse light channel and the far-infrared light channel to remain closed, and after detecting the exposure feedback signal, synchronously controls the measurement light channel to output the measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, so that the fluorescence camera can acquire the light-adaptive fluorescence frame image within the real exposure window. During the maximum fluorescence acquisition phase, the hard real-time synchronization control unit controls the active light channel to continuously output the active light signal and controls the far-infrared light channel to remain closed. After detecting the exposure feedback signal, it synchronously controls the saturated pulse light channel to output the saturated pulse light signal and the measurement light channel to output the measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, so that the fluorescence camera can acquire the maximum fluorescence frame image within the real exposure window. During the minimum fluorescence acquisition stage, the hard real-time synchronization control unit controls the action light channel, the saturated pulse light channel and the far-infrared light channel to remain closed. After detecting the exposure feedback signal, it controls the measurement light channel to output a measurement light signal to read the chlorophyll fluorescence signal produced by the target plant, so that the fluorescence camera can acquire the minimum fluorescence frame image within the real exposure window.

6. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 4, characterized in that, The chlorophyll fluorescence detection and control module is also equipped with: The frame image quality control unit is connected to the chlorophyll fluorescence imaging module and the hard real-time synchronization control unit, respectively, and is used to mark each fluorescence frame image as reliable, low reliable or invalid based on preset fluorescence frame image quality control conditions in each fluorescence acquisition stage. The quality control conditions for the fluorescence frame image include at least the following: whether the fluorescence camera drops frames; whether the fluorescence frame image is overexposed; whether the fluorescence frame image is underexposed; whether the background of the fluorescence frame image is too high; whether the area of ​​interest in the fluorescence frame image is insufficient; whether the outline of the target plant in the fluorescence frame image is clear; whether the saturated pulse light signal is sufficient, whether the working light signal is stable, whether the non-working light signal is leaked, and whether the functional light source is overheated when acquiring the fluorescence frame image.

7. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 1, characterized in that, The chlorophyll fluorescence data processing module generates chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data in the following ways: Image correction is performed on each fluorescence frame image in the multi-state frame-level fluorescence measurement data to obtain multiple corrected fluorescence frame images; A reliable corrected fluorescence frame image from each fluorescence acquisition stage is selected as the key fluorescence frame image, and image registration is performed on each key fluorescence frame image. Each key fluorescence frame image is segmented to obtain one or more leaf regions of interest in each key fluorescence frame image, and strong reflective areas and out-of-focus areas are removed to obtain one or more effective leaf regions of interest in each key fluorescence frame image. Pixel values ​​of each effective leaf region of interest within each key fluorescence frame image are extracted, and multiple chlorophyll fluorescence parameter maps of the target plant are generated. Each chlorophyll fluorescence parameter diagram includes at least the following: dark-adapted fluorescence parameter diagram, dark-state maximum fluorescence parameter diagram, light-adapted fluorescence parameter diagram, light-state maximum fluorescence parameter diagram, light-state minimum fluorescence parameter diagram, maximum photochemical quantum efficiency parameter diagram, actual photochemical quantum efficiency parameter diagram, non-photochemical quenching parameter diagram, light-adapted maximum photochemical quantum efficiency parameter diagram, compartment model photochemical quenching parameter diagram, and lake model photochemical quenching parameter diagram.

8. The in-situ chlorophyll fluorescence detection system for plant factories according to claim 7, characterized in that, The chlorophyll fluorescence data processing module extracts the pixel values ​​of each effective leaf region of interest within the key fluorescence frame image of light adaptation, and corrects the extracted pixel values ​​based on each background frame image of light adaptation to obtain the light adaptation fluorescence signal value at each pixel location, thereby generating a light adaptation fluorescence parameter map of the target plant. The chlorophyll fluorescence data processing module also extracts the pixel values ​​of each effective leaf region of interest within the key fluorescence frame image of maximum photodynamic state, and corrects the extracted pixel values ​​based on each background frame image of maximum photodynamic state to obtain the maximum photodynamic fluorescence signal value at each pixel location, thereby generating a maximum photodynamic fluorescence parameter map of the target plant.

9. A method for in-situ detection and control of chlorophyll fluorescence in a plant factory, characterized in that, A chlorophyll fluorescence detection control module applied to the in-situ chlorophyll fluorescence detection system for plant factories as described in any one of claims 1 to 8, comprising: The mobile platform is controlled to move along a preset inspection route within the plant factory and stop at the target inspection station; The mechanical actuator is controlled to move the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module and the target plant maintain a preset working distance and measurement posture; The chlorophyll fluorescence imaging module is controlled to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module. The chlorophyll fluorescence data processing module is controlled to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

10. An in-situ chlorophyll fluorescence detection device for plant factories, characterized in that, include: The chlorophyll fluorescence imaging module is connected to the plant factory inspection robot and can be detachably mounted on the mechanical actuator of the plant factory inspection robot, which is mounted on the mobile platform of the plant factory inspection robot. A chlorophyll fluorescence data processing module is connected to the chlorophyll fluorescence imaging module; The chlorophyll fluorescence detection and control module, connected to the chlorophyll fluorescence imaging module, the chlorophyll fluorescence data processing module, and the mobile platform and mechanical actuator of the plant factory inspection robot, is configured as follows: The mobile platform is controlled to move along a preset inspection route within the plant factory and stop at the target inspection station; The mechanical actuator is controlled to move the chlorophyll fluorescence imaging module closer to the target plant at the target detection station, so that the chlorophyll fluorescence imaging module and the target plant maintain a preset working distance and measurement posture; The chlorophyll fluorescence imaging module is controlled to perform chlorophyll fluorescence imaging on the target plant, obtain multi-state frame-level fluorescence measurement data of the target plant, and send it to the chlorophyll fluorescence data processing module. The chlorophyll fluorescence data processing module is controlled to generate multiple chlorophyll fluorescence parameter maps of the target plant based on the multi-state frame-level fluorescence measurement data.

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