Cultivation device and method for determining growth condition of plant

Abstract

To provide a cultivation device capable of accurately grasping a growth state of a plant, and a method for determining the growth state of the plant.SOLUTION: A cultivation apparatus of the present disclosure includes a housing that accommodates a plant and forms a closed space, an adsorbent that is installed in the housing and adsorbs one of oxygen and carbon dioxide and does not adsorb the other, a heater that heats the adsorbent, a sensor that measures a pressure or a temperature in the housing, an inlet that supplies a specific gas into the housing, an outlet that discharges a gas in the housing, and an arithmetic device that specifies a transition of a pressure or a temperature in the closed space due to adsorption of oxygen or carbon dioxide discharged from the plant by the adsorbent based on a measurement result of the sensor in order to determine a growth state of the plant.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a cultivation device and a method for determining the growth state of a plant. [Background technology]

[0002] Cultivation devices that manage the growth of plants, such as plant factories, are known. For example, Patent Document 1 below describes a plant factory that includes a housing that forms a closed space and plants that are placed inside the housing. It also describes the adsorption of carbon dioxide to prevent the growth of plants from being inhibited. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-047898 Summary of the Invention [Problem to be solved by the invention]

[0004] In a cultivation device, it is important to accurately grasp the growth state of plants. Furthermore, when growing many plants simultaneously, it is preferable to be able to grasp the growth state even in a remote location, as this reduces the effort required for cultivation. The device disclosed in Patent Document 1 can adjust the amount of carbon dioxide in the housing, but cannot determine the growth state of the plants in the housing. Therefore, a method is desired that can determine the growth state of plants even when the housing is in a remote location.

[0005] In view of the above-mentioned problems, the present disclosure aims to provide a cultivation device that can accurately grasp the growth state of a plant and a method for determining the growth state of a plant. [Means for solving the problem]

[0006] In order to achieve the above object, a cultivation device according to a first aspect of the present disclosure includes a housing that accommodates a plant and forms a closed space, an adsorbent material installed in the housing that adsorbs either oxygen or carbon dioxide, a heater that heats the adsorbent material, a sensor that measures the pressure or temperature inside the housing, an inlet that supplies a specific gas into the housing, an outlet that discharges the gas inside the housing, and a computing device that determines, based on the measurement results of the sensor, a change in pressure or temperature in the closed space caused by the adsorbent material adsorbing oxygen or carbon dioxide emitted by the plant in order to determine the growth state of the plant.

[0007] In such a cultivation device, the amount of oxygen or carbon dioxide emitted by the plants in the housing through photosynthesis or respiration can be estimated with high accuracy, making it possible to determine the growth state of the plants.

[0008] A cultivation device according to a second aspect of the present disclosure is the cultivation device according to the first aspect of the present disclosure, further including a darkening device that makes the inside of the housing a dark room.

[0009] In such a cultivation device, the influence of external light can be eliminated.

[0010] A cultivation device according to a third aspect of the present disclosure is the cultivation device according to the first or second aspect of the present disclosure, further including a light collecting device for irradiating the adsorbent with light.

[0011] In such a cultivation device, the energy required to desorb oxygen or carbon dioxide from the adsorbent can be reduced.

[0012] A cultivation device according to a fourth aspect of the present disclosure is the cultivation device according to any one of the first to third aspects of the present disclosure, further including a camera that captures an image of the plant in the housing.

[0013] Such a cultivation device makes it possible to grasp the latest state of the plant, and also to accurately grasp growth indicators such as the current leaf area of ​​the plant.

[0014] A cultivation device according to a fifth aspect of the present disclosure is a cultivation device according to any one of the first to fourth aspects of the present disclosure, further including a shutter that selectively isolates the space between the adsorbent and the housing.

[0015] In such a cultivation device, it becomes possible to selectively perform an adsorption operation using the adsorbent.

[0016] A cultivation device according to a sixth aspect of the present disclosure is the cultivation device according to any one of the first to fifth aspects of the present disclosure, further including a light source installed in the housing.

[0017] In such a cultivation device, plants can be made to actively carry out photosynthesis.

[0018] A cultivation device according to a seventh aspect of the present disclosure is the cultivation device according to any one of the first to sixth aspects of the present disclosure, further including a fan that guides gas in the housing to an outlet.

[0019] In such a cultivation device, the atmosphere inside the housing can be changed in a short period of time.

[0020] A cultivation device according to an eighth aspect of the present disclosure is the cultivation device according to any one of the first to seventh aspects of the present disclosure, wherein the adsorbent is a porous coordination polymer.

[0021] In such a cultivation device, it is possible to prepare an adsorbent according to the object to be adsorbed.

[0022] A method for determining the growth state of a plant according to a ninth aspect of the present disclosure comprises making a housing containing a plant into a dark room, heating an adsorbent material that adsorbs carbon dioxide inside the housing to desorb the carbon dioxide adsorbed by the adsorbent material, making the housing into a closed space with an oxygen atmosphere, starting to measure the pressure or temperature inside the housing, and comparing the progress of the pressure or temperature inside the housing with a predetermined reference value to determine the growth state of the plant.

[0023] In such a method for determining the growth state of a plant, the amount of carbon dioxide emitted by the plant in the housing through respiration can be estimated with high accuracy, making it possible to determine the growth state of the plant.

[0024] A method for determining the growth state of a plant according to a tenth aspect of the present disclosure includes supplying oxygen into a housing containing a plant, making the housing a dark room, desorbing oxygen adsorbed by an adsorbent that adsorbs oxygen, supplying carbon dioxide into the housing to make the housing a closed space with a carbon dioxide atmosphere, irradiating the plant with light, starting to measure the pressure or temperature inside the housing, and comparing the progress of the pressure or temperature inside the housing with a predetermined reference value to determine the growth state of the plant.

[0025] In such a method for determining the growth state of a plant, the amount of oxygen emitted by the plant in the housing through photosynthesis can be estimated with high accuracy, making it possible to determine the growth state of the plant. [Effects of the Invention]

[0026] According to the cultivation device and the method for determining the growth state of a plant of the present disclosure, it is possible to accurately grasp the growth state of a plant. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is an explanatory diagram showing an example of a cultivation device according to a first embodiment of the present disclosure. [Figure 2] 2 is a block diagram showing an example of a hardware configuration of the arithmetic device shown in FIG. 1. FIG. [Figure 3] 1 is a graph showing the relationship between plant growth index and carbon dioxide emission during respiration. [Figure 4] 10 is a graph showing the relationship over time between a plant growth index and the pressure inside the housing when a predetermined time has elapsed since the space was closed. [Figure 5] 1 is a flowchart showing an example of a method for determining a growth state of a plant according to a first embodiment of the present disclosure. [Figure 6] 6 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 5 is executed. [Figure 7] 6 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 5 is executed. [Figure 8] 6 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 5 is executed. [Figure 9] FIG. 10 is an explanatory diagram showing an example of a cultivation device according to a second embodiment of the present disclosure. [Figure 10] 1 is a graph showing the relationship between plant growth index and oxygen emission amount during photosynthesis. [Figure 11] 10 is a graph showing the relationship between a plant growth index and the temperature inside the housing after a predetermined time has elapsed since the housing was made into a closed space. [Figure 12] 10 is a flowchart showing an example of a method for determining a growth state of a plant according to a second embodiment of the present disclosure. [Figure 13] 13 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 12 is executed. FIG. [Figure 14] 13 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 12 is executed. FIG. [Figure 15] 13 is an operation explanatory diagram illustrating each state of the culture device when the method shown in FIG. 12 is executed. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, each embodiment for carrying out the present disclosure will be described with reference to the drawings. Note that the scope necessary for the explanation to achieve the object of the present disclosure will be schematically shown below, and the scope necessary for explaining the relevant parts of the present disclosure will be mainly explained, and the parts for which explanation is omitted will be referred to as publicly known technologies. Furthermore, identical or similar reference numerals will be used for identical or corresponding components in the drawings, and duplicate explanations will be omitted. Furthermore, when a plurality of identical or corresponding components are included in the drawings, only some of them may be referenced to make the drawings easier to understand.

[0029] First Embodiment 1 is an explanatory diagram showing an example of a cultivation apparatus according to a first embodiment of the present disclosure. The cultivation apparatus 1 according to this embodiment can be an apparatus for cultivating plants, for example, one or more vegetables. Note that the type and number of plants cultivated in the cultivation apparatus 1 are not particularly limited.

[0030] The cultivation device 1 includes at least a housing 10 that accommodates a plant P, an adsorbent 12 installed in the housing 10, a heater 14 that heats the adsorbent 12, a pressure sensor 16 as an example of a sensor that measures the pressure inside the housing 10, an inlet 18 that supplies a specific gas into the housing 10, an outlet 20 that discharges gas from inside the housing 10, and a computing device 40 that determines the growth state of the plant P.

[0031] The housing 10 has a cultivation space therein capable of accommodating a plant P, and the inside of the housing can be made into a closed space. The housing 10 may be made of a light-transmitting material and may be capable of being installed in any location.

[0032] The adsorbent 12 is installed within the housing 10 and adsorbs oxygen or carbon dioxide. Specifically, the adsorbent 12 may be one that adsorbs either oxygen or carbon dioxide but not the other. In this embodiment, the adsorbent 12 is made of a material that adsorbs carbon dioxide but does not adsorb oxygen, more specifically, a material that can substantially adsorb only carbon dioxide. A plurality of adsorbents 12 are installed at the bottom of the housing 10 alongside the plants P. The arrangement and number of adsorbents 12 can be adjusted depending on the type of gas to be adsorbed, the size of the housing 10, and the like. Although the shape of the adsorbent 12 is illustrated as a polyhedron in FIG. 1, the shape is not particularly limited and may be determined appropriately depending on the arrangement of the adsorbents 12, and the like.

[0033] In addition, a porous coordination polymer (PCP) may be used as the adsorbent 12 of this embodiment. A porous coordination polymer is a material formed by porous coordination bonds composed of metal ions and crosslinkable organic ligands, and is sometimes called a metal-organic framework (MOF). In the adsorbent 12 containing this porous coordination polymer, the adsorption strength for a specific substance to be adsorbed can be varied depending on the lattice size of the porous coordination polymer and the metal species of the metal ions crosslinked to the organic ligands. Therefore, by using a porous coordination polymer as the adsorbent 12, an adsorbent 12 capable of adsorbing any gas can be easily obtained. Furthermore, the temperature and pressure ranges within which the adsorbent 12 can adsorb a specific substance can be adjusted. Note that the adsorbent 12 may include an optional binder in addition to the porous coordination polymer. In addition, although the present embodiment illustrates an example in which a porous coordination polymer is used as the adsorbent 12, any material capable of selectively adsorbing oxygen or carbon dioxide is usable.

[0034] The heater 14 functions as a heat source for heating the adsorbent 12 to desorb the carbon dioxide adsorbed in the adsorbent 12. The heater 14 can be installed at any position adjacent to the adsorbent 12 installed in the housing 10. A well-known heater such as a sheath heater or an infrared heater can be used as the heater 14.

[0035] The pressure sensor 16 is a sensor capable of measuring the pressure inside the housing 10, and may be configured as an air pressure sensor such as a Si semiconductor sensor. The pressure sensor 16 may be installed in a suitable position inside the housing 10, for example, at the top.

[0036] The inlet 18 is provided at any position on the housing 10 and is composed of an opening for supplying a specific gas into the housing 10 and a pipe connected to this opening. The inlet 18 of this embodiment can supply oxygen as the specific gas. The inlet 18 of this embodiment is provided at a position adjacent to the bottom of the housing 10. The inlet 18 is further provided with an inlet valve 22, which controls the supply of the specific gas. There are no particular restrictions on the type of valve used for the inlet valve 22, and well-known valves such as gate valves, butterfly valves, and ball valves can be used. FIG. 1 shows an example in which a butterfly valve is used, which makes it easy to understand the open / closed state.

[0037] The outlet 20 is composed of an opening for discharging gas inside the housing 10 to the outside of the housing 10, and piping that communicates with this opening. In this embodiment, the outlet 20 is provided at a position adjacent to the top of the housing 10. The outlet 20 is also provided with an outlet valve 24, and by operating this outlet valve 24, the discharge of gas from the housing 10 can be controlled. There are no particular restrictions on the type of valve used for the outlet valve 24, and for example, a valve similar to the inlet valve 22 can be used. The piping that constitutes the outlet 20 and the inlet 18 is preferably made of a light-blocking material.

[0038] In addition to the above-described configuration, the cultivation device 1 according to this embodiment may include a fan 26 for directing gas in the housing 10 to the outlet 20. The fan 26 may be installed, for example, inside a pipe that constitutes the outlet 20. By operating the above-described fan 26, it is possible to adjust the amount of gas discharged from the outlet 20 and the discharge speed thereof.

[0039] Furthermore, in addition to the above-described configuration, the cultivation device 1 according to this embodiment may include a darkening device 28 that is provided around the housing 10 and can turn the inside of the housing 10 into a dark room. This darkening device 28 can be configured as a light-blocking member that surrounds the outer periphery of the housing 10, such as a blackout curtain. It is also preferable that the darkening device 28 can be attached to and detached from the housing 10 by remote control. By employing this darkening device 28, it becomes possible to determine the growth state of the plant P at any time, regardless of the presence or absence of external light.

[0040] Furthermore, in addition to the above-described configuration, the cultivation apparatus 1 according to this embodiment may include a camera 30 installed at a position where the plant P in the housing 10 can be imaged. This camera 30 can be used by a manager of the cultivation apparatus 1 or the like to check the current state of the plant P or to identify the leaf area index (LAI) as an example of a growth index of the plant P, which will be described later. Therefore, by employing the camera 30, it is possible to expect effects such as being able to visually check the current state of the plant from a remote location or updating the growth index in real time.

[0041] Furthermore, in addition to the above-described configuration, the cultivation apparatus 1 according to this embodiment may be provided with a light collecting device 32 for irradiating light onto the adsorbent 12. The light collecting device 32 according to this embodiment is provided on the wall surface of the housing 10 and is composed of a lens that guides external light to the adsorbent 12. Note that the specific configuration and arrangement of the light collecting device 32 are not particularly limited as long as it can collect light onto the adsorbent 12. By employing this light collecting device 32, the adsorbent 12 can be heated using natural light, and the energy required for the desorption process of the adsorbent 12, specifically the electrical energy required to operate the heater 14, can be reduced.

[0042] Furthermore, in addition to the above-described configuration, the cultivation device 1 according to this embodiment may include a shutter 34 that isolates the housing 10 from the adsorbent 12. This shutter 34 may be, for example, a shutter that opens and closes an opening of the storage space in which the adsorbent 12 is installed, and in this embodiment, a shutter 34 that opens and closes an upper opening of the storage space for the adsorbent 12 is exemplified. When this shutter 34 is closed, the adsorbent 12 is isolated from the housing 10 and does not adsorb gas within the housing 10. Therefore, the energy required for the desorption process of the adsorbent 12 and the time required for the desorption process can be reduced.

[0043] Fig. 2 is a block diagram showing an example of the hardware configuration of the arithmetic device shown in Fig. 1. The arithmetic device 40 may be a device capable of executing various controls of the cultivation device 1. In order to determine at least the growth state of the plant P, the arithmetic device 40 identifies the transition of the pressure inside the housing 10 caused by the adsorption by the adsorbent 12 of carbon dioxide emitted by the plant P based on the measurement result of the pressure sensor 16. In order to realize such processing, the arithmetic device 40 includes the configuration described below.

[0044] The arithmetic device 40 can be configured with a microcontroller, a sequencer (Programmable Logic Controller, PLC), a well-known computer, etc. The arithmetic device 40 of this embodiment is configured with a computer, which may include, for example, a processor 41, a ROM (Read Only Memory) 42 and a RAM (Random Access Memory) 43 as examples of memory, a storage 44, an input / output interface 45, and a communication interface 46. Furthermore, these components may be connected to each other so as to be able to communicate with each other via an internal bus.

[0045] The processor 41 may be configured, for example, by a CPU (Central Processing Unit) and may be capable of executing various programs and controlling each component. Specifically, the processor 41 may be capable of reading various programs stored in the ROM 42 or the storage 44 and executing the programs using the RAM 43 as a work area. The processor 41 may be capable of controlling each component constituting the cultivation device 1 and performing various arithmetic processing according to the programs.

[0046] The ROM 42 may be capable of storing various programs and various data, and the RAM 43 may be capable of temporarily storing programs or data as a working area.

[0047] The storage 44 can be composed of a recording medium such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a flash memory, and may store various programs including an operating system and various data necessary to operate the cultivation device 1.

[0048] The input / output interface (I / F) 45 may be an interface for transmitting and receiving data between various components of the cultivation apparatus 1. As shown in FIG. 2, the input / output interface 45 of this embodiment is connected to, for example, the heater 14, the pressure sensor 16, the inlet valve 22, the outlet valve 24, the fan 26, and the camera 30, and transmits and receives data. The components from which the input / output interface 45 acquires data or outputs data are not limited to those described above. For example, a display, a speaker, etc. may be further connected to communicate the determination results to a manager located near the cultivation apparatus 1.

[0049] The communication interface (I / F) 46 is connected to a network NW and realizes data communication with an external device, for example, a management device 3 configured with a PC owned by a manager of the cultivation device 1. Examples of communication standards applied to this communication interface 46 include wireless communication standards including Wi-Fi (registered trademark) and Bluetooth (registered trademark). Examples of the network NW include a wide area network (WAN) and / or a local area network (LAN). Furthermore, the management device 3 may be installed in a location physically separated from the cultivation device 1.

[0050] The arithmetic device 40 having the above-described configuration can realize various processes for managing the cultivation device 1 in addition to determining the growth state of the plant P described above. Furthermore, if the results of the various processes performed by the arithmetic device 40 are transmitted to the management device 3 at a remote location via the communication interface 46, remote monitoring by an administrator is possible, which is preferable. Furthermore, the method for determining the growth state of a plant according to the present embodiment, which will be described later, can be provided in the form of a program such as software including instructions for causing a computer constituting the arithmetic device 40 to execute predetermined operations, in the form of a program product including this program, or in the form of a non-transitory computer-readable recording medium on which this program is stored.

[0051] FIG. 3 is a graph showing the relationship between a plant's growth index and the amount of carbon dioxide emitted during respiration. Generally, there is a correlation between the growth level of a plant P and the amount of carbon dioxide (CO2) M1 emitted by the plant P during respiration. Specifically, as shown by line L1 in FIG. 3, as the leaf area index (LAI) of a plant P, which is an example of a growth index, increases, the amount of CO2 emitted during respiration M1 generally also increases. It is known that, for example, if the plant P is not growing well due to disease or insufficient sunlight, the amount of CO2 emitted during respiration M1 relative to the plant's growth index decreases compared to when the plant is growing well, as shown by line L2 in FIG. 3. The cultivation device 1 of this embodiment focuses on this point and attempts to determine the growth state of the plant P. Note that the correlation shown by lines L1 and L2 in FIG. 3 is merely an example, and depending on the plant, lines L1 and L2 may be curved rather than straight.

[0052] Specifically, in the cultivation device 1 according to the present embodiment, in order to determine whether the growth condition of the plant P is good or not, the above-mentioned adsorbent 12 that adsorbs substantially only CO2 is disposed inside the housing 10 that can form a closed space. Then, by detecting a change in the pressure value inside the closed space that occurs when the adsorbent 12 adsorbs the CO2 emitted by the plant P through respiration, the amount of CO2 emitted by the plant P through respiration can be accurately estimated.

[0053] FIG. 4 is a graph showing the relationship between the plant growth index and the pressure inside the closed housing over time. In the above-described cultivation apparatus 1, for example, when a plant P in good growth condition is being cultivated, the pressure P inside the closed housing 10 is a value that gradually decreases relative to the reference pressure P0 (often equal to atmospheric pressure) as shown by line L3, depending on the growth index of the plant P. On the other hand, in the same cultivation apparatus 1, for example, when a plant P in poor growth condition is being cultivated, the pressure P inside the closed housing 10 is a value that gradually decreases relative to the reference pressure P0 as shown by line L4, depending on the growth index of the plant P, similar to when a plant P in good growth condition is being cultivated, but the rate of decrease is gentler than when the plant is in good growth condition. The arithmetic unit 40 of the present embodiment determines whether the plant P is in good growth condition based on the difference in the change in pressure value.

[0054] 4 shows line L4 as an example of pressure P when a plant P in poor growth condition is being cultivated, but line L4 is merely an example of a detected pressure value, and the slope and value of line L4 may vary depending on various conditions. Furthermore, the transitions of reference pressure P0, line L3, and the line indicating the reference value that indicates the upper limit of the degree of pressure reduction corresponding to the amount of CO2 emitted by a plant P in good growth condition through respiration depend on the temperature inside the housing 10. In relation to this, it is advisable to adjust reference pressure P0, the reference value, etc., according to the temperature inside the housing 10.

[0055] The computing device 40 of this embodiment can determine the growth condition of a plant by, for example, comparing the pressure value measured by the pressure sensor 16 with a preset reference value. Specifically, the upper limit of the degree of pressure decrease corresponding to the amount of CO2 emitted by a plant P in good growth condition through respiration is set as the reference value, and the determination can be made based on whether the pressure value measured by the pressure sensor 16 is lower than the reference value. The pressure value measured by the pressure sensor 16 may also be compared with the reference value as a displacement from the reference pressure P0. Instead of comparing the pressure value at a specific time point with the reference value, it is also possible to determine that the growth condition is not good if the slope of line L4 with respect to the reference pressure P0 is equal to or smaller than the slope of the line indicating the reference value (e.g., line L3) with respect to the reference pressure P0. The timing of pressure measurement by the pressure sensor 16 is not particularly limited, and the number of times may be one or multiple times at predetermined time intervals. The average value of multiple measurement results may also be compared with the reference value.

[0056] As described above, according to the cultivation device 1 of this embodiment, the growth state of the plant can be determined based on the detection results of the sensor, so that even if the manager is in a remote location from the cultivation device 1, the growth state of the plant can be automatically and accurately grasped.

[0057] In this embodiment, a configuration is adopted in which the calculation device 40 and the management device 3 are connected via a network NW so that various information about the cultivation device 1 can be confirmed by the management device 3, but some of the functions of the calculation device 40 may also be performed by the management device 3.

[0058] Next, a method for determining the growth state of a plant according to this embodiment will be described with reference to Figs. 5 to 8. In the following description, a case where the growth state of a plant is determined using the above-described cultivation device 1 will be exemplified, but the method can also be realized using a cultivation device other than the cultivation device 1. Furthermore, this method can be performed mainly based on a control signal from the calculation device 40. Furthermore, the effects of the method for determining the growth state of a plant described below also include the effects of the cultivation device 1.

[0059] The method for determining the growth state of a plant according to this embodiment includes at least the steps of making the inside of housing 10 containing plant P a dark room (corresponding to step S01 described later), heating adsorbent 12 that adsorbs carbon dioxide in housing 10 to desorb the carbon dioxide adsorbed by the adsorbent (corresponding to step S02 described later), making the inside of housing 10 a closed space with an oxygen atmosphere (corresponding to steps S03 and S04 described later), starting to measure the pressure inside housing 10 (corresponding to step S05 described later), and comparing the progress of the pressure inside the housing with a predetermined reference value to determine the growth state of the plant (corresponding to steps S06 to S08 described later). These steps will be described in detail below.

[0060] Fig. 5 is a flowchart showing an example of a method for determining the growth state of a plant according to the first embodiment of the present disclosure. Figs. 6 to 8 are operation explanatory diagrams illustrating each state of the cultivation device when the method shown in Fig. 5 is executed. Note that Figs. 6 to 8 schematically show carbon dioxide (CO2) and oxygen (O2) molecules to make it easier to understand the atmosphere inside the housing 10. In Figs. 6 to 8, some components unrelated to the operations executed by the cultivation device 1 and their reference numerals are omitted to make the drawings easier to understand.

[0061] As shown in Fig. 6(A), before carrying out the method for determining the growth state of a plant according to this embodiment, the cultivation apparatus 1 has the darkening device 28 removed so that external light is irradiated into the housing 10, and the inlet valve 22 and the outlet valve 24 are open. At this time, it is preferable that the shutter 34 be closed. When the shutter 34 is closed, the adsorption of CO2 within the housing 10 by the adsorbent 12 is substantially stopped, and therefore the energy and time required for the desorption process of the adsorbent 12, which will be described later, can be reduced compared to when the shutter 34 is not closed or when the shutter 34 is not provided.

[0062] When the method for determining the growth state of a plant according to this embodiment is started from the state shown in Fig. 6(A), first, as shown in Fig. 6(B), a darkening device 28 is attached around the housing 10 to change the inside of the housing 10 into a dark room (step S01). Note that the time and frequency for performing the method for determining the growth state of a plant according to this embodiment are not particularly limited. Furthermore, when the method is performed at a time when external light is not irradiated into the housing 10, such as at night, the step of changing the inside of the housing 10 into a dark room using the darkening device 28 can be omitted.

[0063] The computing device 40 also opens the shutter 34 and operates the heater 14 to desorb CO2 adsorbed on the adsorbent 12 (step S02). Then, O2 is supplied into the housing 10 from the inlet 18 (step S03). When O2 is supplied from the inlet 18, the outlet valve 24 is kept open, so that the CO2 and O2 that filled the housing 10 are discharged from the outlet 20 to the outside of the housing 10. Note that the order of performing the above-described steps S01 to S03 is not limited to the above order and can be changed as appropriate, and the steps can also be performed in parallel.

[0064] After the housing 10 is filled with an oxygen atmosphere by supplying O2 from the inlet 18 for a predetermined time, the inlet valve 22 and the outlet valve 24 are closed to close the housing 10, creating a closed space, as shown in Fig. 7(A) (step S04). Then, measurement of pressure values ​​by the pressure sensor 16 begins (step S05). Note that the "atmosphere" mentioned here means that the majority of the gas in the housing 10 is a specific gas, in this embodiment oxygen, and does not mean that all gases other than oxygen in the housing 10 have been completely discharged.

[0065] By creating a darkened, enclosed space with an oxygen atmosphere within the housing 10, the plant P within the housing 10 temporarily only respires. As this respiration occurs, CO2 is emitted from the plant P, as shown in FIG. 7(B). Because the emitted CO2 is heavier than O2, it moves downward within the housing 10 and is adsorbed onto the adsorbent 12, as shown in FIG. 8(A). When the adsorbent 12 adsorbs the CO2, the adsorption reduces the pressure within the housing 10. The computing device 40 determines, based on the progression of the pressure measured by the pressure sensor 16, whether the measured pressure value exceeds a preset reference value (step S06). Here, the preset reference value may be a value that is set in accordance with the elapsed time since the start of measurement by the pressure sensor 16 and defines the upper limit of the pressure value expected when the plant P is growing well.

[0066] The above-described step S06 may be performed when a predetermined time has elapsed since the start of measurement of the pressure inside the housing 10. If, in step S06, the pressure value measured by the pressure sensor 16 is below the reference value, i.e., the pressure value measured by the pressure sensor 16 is lower than the reference value as the upper limit of pressure expected when the plant P is growing well (Yes in step S06), the calculation device 40 determines that a sufficient amount of CO2 is being emitted from the plant P and that the plant P is respiring normally, and determines that the plant P is growing well (step S07). On the other hand, if the pressure value measured by the pressure sensor 16 is equal to or greater than the reference value, i.e., the pressure value measured by the pressure sensor 16 is equal to or greater than the reference value as the upper limit of pressure expected when the plant P is growing well (No in step S06), the calculation device 40 determines that a sufficient amount of CO2 is not being emitted from the plant P and that the plant P is not respiring normally, and determines that the plant P is growing poorly (step S08).

[0067] According to the method for determining the growth state of a plant according to this embodiment, by executing the series of processes described above, it is possible to determine whether the growth state of the plant P is good or not. Then, by transmitting the determination result of the growth state of the plant P to, for example, the management device 3 and notifying the manager of the cultivation device 1, the manager can immediately grasp the growth state of the plant P cultivated by the cultivation device 1 located in a remote place.

[0068] Furthermore, for example, if a manager finds that the growth condition of the plants P in the cultivation device 1 is poor, the manager can obtain the image data of the camera 30 to check the condition of the plants P in real time. The manager can also use this image data to determine a policy for improving the growth condition before moving the cultivation device 1 to a location where it is installed.

[0069] After the series of processes described above is completed, the inlet valve 22 and the outlet valve 24 are opened and the darkening device 28 is removed, as shown in Fig. 8(B). Then, external light, for example, sunlight, is concentrated on the adsorbent 12 via the light concentrator 32 to assist the desorption process of the adsorbent 12.

[0070] <Second embodiment> In the cultivation apparatus 1 and the method for determining the growth state of a plant according to the first embodiment described above, the adsorbent 12 for adsorbing CO2 and the pressure sensor 16 are mainly used as an example. However, the present disclosure is not limited thereto. Therefore, as a second embodiment of the present disclosure, a cultivation apparatus 1A including an adsorbent and a sensor different from those of the first embodiment and a method for determining the growth state of a plant using the same will be described below. Note that many of the components of the cultivation apparatus 1A described below may be at least partially similar to those of the cultivation apparatus 1 of the first embodiment. Therefore, the following description will focus on the differences between the various components of the cultivation apparatus 1A according to the present embodiment and those of the first embodiment. Detailed descriptions of the components similar to those of the first embodiment will be omitted, as the description of the first embodiment will be reused.

[0071] Fig. 9 is an explanatory diagram showing an example of a cultivation apparatus according to a second embodiment of the present disclosure. As shown in Fig. 9, the cultivation apparatus 1A according to this embodiment includes a housing 10A that accommodates a plant P, an adsorbent 12A installed in the housing 10A, a heater 14 that heats the adsorbent 12A, a temperature sensor 16A as an example of a sensor that measures the temperature inside the housing 10A, an inlet 18A that supplies a specific gas into the housing 10A, an outlet 20A that discharges the gas inside the housing 10A, and a computing device 40A that determines the growth state of the plant P. Of these, the computing device 40A may have the same basic structure as the computing device 40 of the cultivation apparatus 1 described above, although the controlled object is partially different.

[0072] The housing 10A may have the same configuration as the housing 10 described above, except that it has a space for installing the heater 14A at the top and does not have the light collecting device 32 on its wall surface.

[0073] The adsorbent 12A is installed within the housing 10A and adsorbs oxygen. Specifically, the adsorbent 12A is configured to adsorb oxygen but not carbon dioxide. The adsorbent 12A of this embodiment employs a porous coordination polymer that substantially adsorbs only oxygen. Furthermore, a plurality of adsorbents 12A are installed in the upper part of the housing 10A. By being installed in the upper part of the housing 10A, the adsorbent 12A can efficiently adsorb oxygen, which is relatively light. In addition, the adsorbent 12A of this embodiment generates adsorption heat when adsorbing oxygen. The heater 14A may have the same configuration as the heater 14 described above, except that it is installed above the housing 10A in accordance with the arrangement of the adsorbent 12A described above.

[0074] The temperature sensor 16A is a sensor capable of measuring the temperature inside the housing 10, and may be a contact-type temperature sensor, typically using a thermocouple or bimetal, or a non-contact-type temperature sensor using an infrared sensor. In this embodiment, the temperature sensor 16A is a contact-type temperature sensor, and is installed adjacent to a specific adsorbent 12A, more specifically, within the space containing the adsorbent 12A, to detect the temperature rise inside the housing 10A with high accuracy and without variation. The location of the temperature sensor 16A is not particularly limited as long as it can accurately detect the temperature rise caused by the heat generated by the adsorbent 12A. Alternatively, multiple temperature sensors 16A may be installed adjacent to different adsorbents 12A, and the temperature rise inside the housing 10A may be detected using the detection results.

[0075] The inlet 18A is composed of an opening for supplying a specific gas into the housing 10A and a pipe connected to the opening. In this embodiment, the inlet 18A can selectively supply oxygen and carbon dioxide as the specific gas. The inlet 18A is provided adjacent to the top of the housing 10A. The outlet 20A may have the same configuration as the outlet 20 described above, except that it is provided adjacent to the bottom of the housing 10A.

[0076] The cultivation apparatus 1A of this embodiment is similar to the above-described cultivation apparatus 1 in that it includes a blackout device 28, a camera 30, and a shutter 34. The cultivation apparatus 1A also includes a light source 36 in the housing 10A that irradiates the plant P with light.

[0077] The light source 36 is installed in an appropriate position within the housing 10A, for example, on one side, and irradiates light onto the plant P. This light source 36 can be a light source capable of irradiating visible light including blue and red, such as an incandescent bulb, a fluorescent lamp, or an LED (Light Emitting Diode). The number and arrangement of the light sources 36 are not particularly limited and can be adjusted depending on the arrangement and type of the plant P.

[0078] In this embodiment, the light source 36 is illuminated while the outer periphery of the housing 10A is covered with the above-described blackout device 28, thereby creating an environment in which the plant P can perform photosynthesis. In this way, by artificially creating an environment in which the plant P can perform photosynthesis using the blackout device 28 and the light source 36, the plant P can perform photosynthesis under a stable amount of light irradiation, and the growth state of the plant P can also be accurately determined. Note that if a stable amount of light irradiation similar to the above-described environment can be obtained by using external light (including sunlight), the blackout device 28 and the light source 36 can be omitted.

[0079] FIG. 10 is a graph showing the relationship between a plant's growth index and the amount of oxygen (O2) emitted during photosynthesis. Generally, there is a correlation between the growth level of a plant P and the amount of oxygen (O2) M2 emitted by the plant P during photosynthesis. Specifically, as shown by line L5 in FIG. 10, as the leaf area index (LAI) of a plant P, which is an example of a growth index, increases, the amount of O2 emitted during photosynthesis M2 also generally increases. It is known that when the plant P is not growing well due to, for example, disease or insufficient sunlight, the amount of O2 emitted during photosynthesis M2 relative to the plant's growth index decreases compared to when the plant is growing well, as shown by line L6 in FIG. 10. The cultivation device 1A of this embodiment focuses on this point and attempts to determine the growth state of the plant P. Note that the correlation shown by lines L5 and L6 in FIG. 10 is merely an example, and depending on the plant, lines L5 and L6 may be curved rather than straight.

[0080] Specifically, in the cultivation apparatus 1A according to the present embodiment, the adsorbent 12A that substantially adsorbs only O2 is disposed in a housing 10A capable of forming a closed space in order to determine whether the growth condition of the plant P is good. The cultivation apparatus 1A detects a temperature change in the closed space that occurs when the adsorbent 12A adsorbs the O2 emitted by the plant P through photosynthesis, thereby accurately estimating the amount of O2 emitted by the plant P through photosynthesis.

[0081] 11 is a graph showing the relationship between the growth index of a plant and the temperature inside the housing 10A a predetermined time after the housing 10A is closed. In the above-described cultivation apparatus 1A, for example, when a plant P in good growth condition is being cultivated, the temperature ΔT inside the housing 10A when the housing 10A is closed is, as shown by line L7, a reference temperature T0, which is the temperature when the housing 10A is closed (often equal to the outside air temperature). The temperature ΔT rises from the reference temperature T0 in accordance with the growth index of the plant P due to heat generated when the adsorbent 12A adsorbs O2, as shown by line L8. In the same cultivation apparatus 1A, for example, when a plant P in poor growth condition is being cultivated, the temperature ΔT inside the housing 10A when the housing 10A is closed is, as shown by line L8, a more gradual increase than that of a plant in good growth condition with a similar growth index, because the amount of O2 adsorbed by the adsorbent 12A is relatively small. The arithmetic device 40A of the present embodiment determines whether the growth condition of the plant P is good or not based on such a difference in temperature change.

[0082] The computing device 40A of this embodiment can determine the growth state of a plant by, for example, comparing the temperature measured by the temperature sensor 16A with a preset reference value (e.g., indicated by line L7). Specifically, the reference value is the lower limit of the temperature rise inside the housing 10A corresponding to the amount of O2 emitted by plants P in good growth state through photosynthesis, and the determination can be made based on whether the temperature measured by the temperature sensor 16A is higher than the reference value. The reference value is preferably adjusted to match the reference temperature T0. This is because the amount of temperature change caused by the adsorption of O2 by the adsorbent 12A when the reference temperature T0 is high is smaller than when the reference temperature T0 is low.

[0083] With the above-described configuration, the cultivation apparatus 1A according to this embodiment can also obtain the same effects as those of the cultivation apparatus 1A according to the first embodiment described above.

[0084] Next, a method for determining the growth state of a plant according to this embodiment will be described with reference to Figures 12 to 15. In the following description, a case where the growth state of a plant is determined using the above-described cultivation device 1A will be exemplified.

[0085] The method for determining the growth state of a plant according to this embodiment includes the steps of supplying oxygen into housing 10A containing plant P (step S11, described later), making housing 10A a dark room (step S12, described later), desorbing oxygen adsorbed by oxygen-adsorbing adsorbent 12A (step S13, described later), supplying carbon dioxide into housing 10A to make housing 10A a closed space with a carbon dioxide atmosphere (steps S15 and S16, described later), irradiating plant P with light (step S17, described later), starting to measure the temperature inside housing 10A (step S18, described later), and comparing the temperature change inside the housing with a predetermined reference value to determine the growth state of the plant (steps S19 to S21, described later). These steps will be described in detail below.

[0086] Fig. 12 is a flowchart showing an example of a method for determining the growth state of a plant according to the second embodiment of the present disclosure. Figs. 13 to 15 are operation explanatory diagrams illustrating each state of the cultivation apparatus when the method shown in Fig. 12 is executed. In Figs. 13 to 15, carbon dioxide (CO2) and oxygen (O2) molecules are schematically shown to make it easier to understand the atmosphere inside the housing 10A. In Figs. 13 to 15, some components and their reference numerals that are not related to the operations executed by the cultivation apparatus 1A are omitted to make the drawings easier to understand.

[0087] Before carrying out the method for determining the growth state of a plant according to this embodiment, the cultivation apparatus 1A may have the blackout device 28 removed so that external light can be irradiated into the housing 10A, and the inlet valve 22 and the outlet valve 24 open, as shown in Fig. 13(A). At this time, the shutter 34 is closed.

[0088] When the method for determining the growth state of a plant according to this embodiment is started from the state shown in Fig. 13(A), first, O2 is supplied into the housing 10A from the inlet 18A (step S11) as shown in Fig. 13(B). Here, the reason for supplying O2 into the housing 10A first is to prevent the plant P from becoming weak when the housing 10A is filled with a carbon dioxide atmosphere in the subsequent process.

[0089] Next, a darkening device 28 is attached around the housing 10A to convert the inside of the housing 10A into a dark room (step S12). The shutter 34 is opened and the heater 14A is operated to desorb the O2 adsorbed on the adsorbent 12A (step S13). After the O2 desorption from the adsorbent 12A is completed, the supply of O2 from the inlet 18A is stopped (step S14).

[0090] 14(A), CO2 is supplied into the housing 10A from the inlet 18A (step S15). When CO2 is supplied from the inlet 18A, the outlet valve 24 is kept open, so that the O2 and CO2 that filled the housing 10A are discharged to the outside of the housing 10A from the outlet 20A.

[0091] After the housing 10A is filled with a carbon dioxide atmosphere by supplying CO2 from the inlet 18A for a predetermined time, the inlet valve 22 and the outlet valve 24 are closed to close the housing 10A to form a closed space (step S16), as shown in Fig. 14(B). Then, the light source 36 is turned on (step S17), and temperature measurement by the temperature sensor 16A is started (step S18).

[0092] By creating a darkened, enclosed space with a carbon dioxide atmosphere within the housing 10A and irradiating the plant P with light from the light source 36, the plant P within the housing 10A essentially performs only photosynthesis. As photosynthesis occurs, O2 is emitted from the plant P, as shown in FIG. 15(A). Because the emitted O2 is lighter than CO2, it moves upward within the housing 10A and is adsorbed onto the adsorbent 12A, as shown in FIG. 15(B). When the adsorbent 12A adsorbs O2, the heat of adsorption generated during the adsorption increases the temperature within the housing 10A. The computing device 40A determines whether the measured temperature measured by the temperature sensor 16A exceeds a preset reference value (step S19). The preset reference value may be a value that defines a lower limit of a gradually increasing temperature, set in accordance with the elapsed time since the start of measurement by the temperature sensor 16A.

[0093] The above-described step S19 may be performed when a predetermined time has elapsed since measurement of the temperature inside the housing 10A was started. If the temperature measured by the temperature sensor 16A exceeds the reference value in step S19, i.e., if the temperature measured by the temperature sensor 16A is higher than the lower limit of the temperature assumed as the reference value (Yes in step S19), the calculation device 40A determines that the plant P is performing photosynthesis normally and that its growth condition is good (step S20). On the other hand, if the temperature measured by the temperature sensor 16A is equal to or lower than the reference value, i.e., if the temperature measured by the temperature sensor 16A is equal to or lower than the lower limit of the temperature assumed as the reference value (No in step S19), the calculation device 40A determines that the plant P is not performing photosynthesis normally and that its growth condition is poor (step S21).

[0094] In step S19 described above, the calculation device 40A compares the temperature measured by the temperature sensor 16A with a reference value, but it may also be configured to calculate a temperature change from the temperature measured by the temperature sensor 16A and compare the temperature change with a preset reference value that corresponds to the temperature change. Using the temperature change in this way eliminates the need to consider the temperature (which is often the same as the outside air temperature) at the start of the above-described method.

[0095] The method for determining the growth state of a plant according to this embodiment can also achieve the same effects as those of the first embodiment described above.

[0096] In the method for determining the growth state of a plant according to the first embodiment described above, the case where the growth state of a plant is determined based on the transition of pressure inside the housing has been exemplified, but it is also possible to determine the growth state of a plant based on the transition of temperature (described in the second embodiment) instead of pressure. Similarly, in the method for determining the growth state of a plant according to the second embodiment, the case where the growth state of a plant is determined based on the transition of temperature inside the housing has been exemplified, but it is also possible to determine the growth state of a plant based on the transition of pressure (described in the first embodiment) instead of temperature.

[0097] Alternatively, the adsorbent 12 described in the first embodiment and the adsorbent 12A described in the second embodiment may be disposed in a single housing, so that both of the methods for determining the growth state of plants described in each embodiment can be performed within the same housing. In this case, it is preferable to selectively open and close shutters 34 covering the adsorbents 12 and 12A so that the adsorbent to be used for adsorption can be selected.

[0098] The present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. All of these modifications are included in the technical concept of the present disclosure. Furthermore, unless otherwise specified in the specification, each component of the present disclosure is not limited to one, and may be present in multiple forms. [Explanation of symbols]

[0099] 1, 1A cultivation equipment 10, 10A housing 12, 12A Adsorbent 14, 14A heater 16 Pressure sensor (example of a sensor) 16A temperature sensor (example of a sensor) 18, 18A entrance 20, 20A exit 22 Inlet valve 24 Outlet valve 26 Fans 28 Blackout Device 30 Camera 32 Light Concentrator 34 Shutter 36 light source 40, 40A arithmetic unit P plant

Claims

1. a housing that houses the plant and forms a closed space; an adsorbent disposed within the housing and configured to adsorb either oxygen or carbon dioxide; a heater for heating the adsorbent; a sensor for measuring pressure or temperature within the housing; an inlet for supplying a specific gas into the housing; an outlet for discharging gas within the housing; and a computing device that identifies a change in pressure or temperature in the closed space caused by the adsorption of oxygen or carbon dioxide emitted by the plant by the adsorbent based on the measurement result of the sensor in order to determine the growth state of the plant. Cultivation equipment.

2. Further provided is a darkening device that makes the inside of the housing a dark room. The cultivation device according to claim 1.

3. Further comprising a light collecting device for irradiating the adsorbent with light. The cultivation device according to claim 1.

4. further comprising a camera for capturing images of the plants within the housing; The cultivation device according to claim 1.

5. a shutter for selectively isolating the space between the adsorbent and the housing; The cultivation device according to claim 1.

6. further comprising a light source disposed within the housing; The cultivation device according to claim 1.

7. Further comprising a fan for directing gas within the housing to an outlet. The cultivation device according to claim 1.

8. The adsorbent is a porous coordination polymer. The cultivation device according to claim 1.

9. The housing containing the plants is used as a dark room. heating an adsorbent that adsorbs carbon dioxide within the housing to desorb the carbon dioxide adsorbed by the adsorbent; The inside of the housing is a closed space with an oxygen atmosphere, initiate a measurement of pressure or temperature within the housing; The change in pressure or temperature inside the housing is compared with a predetermined reference value to determine the growth state of the plant. A method for determining the growth status of plants.

10. Supplying oxygen to the housing containing the plants; The inside of the housing is a darkroom, desorbing oxygen adsorbed in the adsorbent; supplying carbon dioxide into the housing to form a closed space in a carbon dioxide atmosphere inside the housing; Irradiating the plant with light; initiate a measurement of pressure or temperature within the housing; The change in pressure or temperature inside the housing is compared with a predetermined reference value to determine the growth state of the plant. A method for determining the growth status of plants.

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