Harvest determination device

Abstract

To accurately determine timing for harvesting a harvesting object of a plant.SOLUTION: The harvest determination apparatus 100 includes a detection unit 110, a noise removal signal acquisition unit 120, a noise removal unit 130, and a determination unit 140. The detection unit 110 detects light transmitted through or reflected by the harvesting target F (hereinafter, referred to as detection light) and generates a detection signal. The noise removal signal acquisition unit 120 acquires a signal (hereinafter, referred to as a noise removal signal) for removing noise included in the detection signal. The noise removal unit 130 generates a noise-removed detection signal (hereinafter, referred to as a determination signal) using the detection signal and the noise removal signal. The determination unit 140 determines the harvest timing of the harvesting target using the determination signal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a harvest determination device. [Background technology]

[0002] The economic value of harvested plants, such as fruits, is largely determined by the content of specific components (such as sugar content) contained in the harvested product. Generally, when harvested products are important for sugar content, the sugar content is measured after harvesting using near-infrared light irradiation and an optical sensor.

[0003] For example, Patent Document 1 describes measuring the sugar content distribution in a harvest object by irradiating the harvest object with light while rotating a light source relative to the harvest object and then spectroscopically analyzing the light that passes through the harvest object. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-24651 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, the economic value of harvested plants, such as fruits, is largely determined by the amount of specific components contained in the harvested plants. Therefore, the economic value of the harvested plants is determined by the timing of harvesting the plants. Here, it is conceivable to determine the timing of harvesting by measuring the amount of specific components contained in the harvested plants using optical techniques.

[0006] One example of a problem to be solved by the present invention is to be able to accurately determine the timing for harvesting a plant to be harvested. [Means for solving the problem]

[0007] The invention described in claim 1 comprises: a detection unit that detects detection light transmitted through or reflected from a harvest object and generates a detection signal; a noise-removed signal acquisition unit that acquires a noise-removed signal included in the detection signal; a noise removal unit that uses the detection signal and the noise-removed signal to generate a judgment signal, which is the detection signal after noise removal; a determination unit that determines the harvest timing of the harvest target object based on the determination signal; This is a harvest judgment device equipped with the above. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing the configuration of a harvest assessment device according to an embodiment. FIG. [Figure 2] 1 is a diagram showing the configuration of a harvest assessment device according to a first embodiment. [Figure 3] FIG. 10 is a diagram showing the configuration of a harvest assessment device according to a second embodiment. [Figure 4] FIG. 10 is a diagram showing the configuration of a harvest assessment device according to a third embodiment. [Figure 5] FIG. 10 is a diagram showing the configuration of a harvest assessment device according to a fourth embodiment. [Figure 6] FIG. 10 is a diagram showing the configuration of a plant growing device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, like components are designated by like reference numerals, and the description thereof will be omitted as appropriate.

[0010] In the following description, each component of the harvest assessment device 100 is represented as a functional block, rather than as a hardware configuration. Each component of the harvest assessment device 100 is implemented by any combination of hardware and software, centered around the CPU of any computer, memory, a program loaded into memory, a storage medium such as a hard disk that stores the program, and a network connection interface. There are many variations on the implementation method and device.

[0011] FIG. 1 is a diagram illustrating the configuration of a harvest assessment apparatus 100 according to an embodiment. The harvest assessment apparatus 100 according to this embodiment includes a detection unit 110, a noise-removed signal acquisition unit 120, a noise removal unit 130, and a determination unit 140. The detection unit 110 detects light (hereinafter referred to as detection light) transmitted through or reflected from a harvest target F and generates a detection signal. The noise-removed signal acquisition unit 120 acquires a signal (hereinafter referred to as a noise-removed signal) for removing noise contained in the detection signal. The noise removal unit 130 uses the detection signal and the noise-removed signal to generate a noise-removed detection signal (hereinafter referred to as a determination signal). The determination unit 140 uses the determination signal to determine the timing of harvesting the harvest target. The harvest target F may be, for example, fruit such as melon, watermelon, peach, apple, or mango, but is not limited thereto. The harvest assessment apparatus 100 is used, for example, but not limited to, a plant factory. The following provides a detailed description of the harvest assessment apparatus 100.

[0012] The harvest assessment device 100 assesses the timing of harvesting based on the concentration of a specific component (hereinafter referred to as the specific component) contained in the harvest target F. For this reason, the wavelength of the light detected by the detection unit 110 is determined according to the type of specific component. For example, if the specific component is sugar, the light detected by the detection unit 110 will be near-infrared light.

[0013] The detection unit 110 generates a detection signal by photoelectrically converting light that has passed through or reflected from the harvest target F. The detection unit 110 may have an amplifier circuit that amplifies the detection signal. The light source of the light detected by the detection unit 110 has a light-emitting element such as an LED or an organic EL element, and is placed near the harvest target F.

[0014] The detection signal generated by the detection unit 110 contains various noises. These noises include, for example, noise derived from light of a wavelength other than that to be detected by the detection unit 110 (for example, light in a wavelength range other than near-infrared light) and noise derived from elements (for example, a photoelectric conversion element or an amplifier circuit) included in the detection unit 110. The noise-removed signal acquisition unit 120 acquires a signal containing these noises as the noise-removed signal. Specific examples of the noise-removed signal will be described later using examples.

[0015] The noise removal unit 130 removes noise from the detection signal by subtracting the noise-removed signal from the detection signal. This generates a determination signal. The relative ratio of the amplification factors of the detection signal and the noise-removed signal immediately before the subtraction process is set so that the noise contained in the determination signal is small (preferably minimized).

[0016] The judgment unit 140 judges whether or not the harvest target F should be harvested based on the strength of the judgment signal. For example, the judgment unit 140 judges that the harvest target F should be harvested when the strength of the judgment signal is below a reference value (or above the reference value). The judgment result is output to the outside, for example, as an image signal or an audio signal. Here, the judgment unit 140 may calculate the concentration or distribution of a specific component (for example, sugar content) contained in the harvest target F from the judgment signal, and compare the calculation result with a reference value or reference distribution to judge whether or not the harvest target F should be harvested.

[0017] As described above, according to this embodiment, the noise removal unit 130 removes noise from the detection signal detected by the detection unit 110 by subtracting the noise-removed signal from the detection signal. The determination unit 140 then uses the noise-removed signal (determination signal) generated by the noise removal unit 130 to determine whether or not the harvest target F should be harvested. Therefore, the timing to harvest the plant to be harvested can be determined with high accuracy. [Example]

[0018] Example 1 2 is a diagram showing the configuration of a harvest assessment apparatus 100 according to Example 1. The harvest assessment apparatus 100 according to this example has the same configuration as the harvest assessment apparatus 100 according to the embodiment, except for the following points.

[0019] First, light from the harvest target F is incident on both the detection unit 110 and the noise-removed signal acquisition unit 120, for example, simultaneously.

[0020] The detection unit 110 has a first filter unit 112, a first photoelectric conversion unit 114, and an amplification unit 116. The first filter unit 112 transmits light in a wavelength range to be analyzed (hereinafter referred to as light in a first wavelength range) out of light (detection light) incident on the detection unit 110, and cuts light in other wavelength ranges. The first photoelectric conversion unit 114 photoelectrically converts the light that has transmitted through the first filter unit 112 to generate a detection signal. The amplification unit 116 amplifies the detection signal generated by the first photoelectric conversion unit 114 and outputs it to the noise removal unit 130.

[0021] The noise-removed signal acquisition unit 120 also has a second filter unit 122, a second opto-electrical conversion unit 124, and an amplifier unit 126. The second filter unit 122 cuts off light in a first wavelength range. The second opto-electrical conversion unit 124 performs photoelectric conversion on the light that has passed through the second filter unit 122 to generate a noise-removed signal. The amplifier unit 126 amplifies the noise-removed signal generated by the second opto-electrical conversion unit 124 and outputs the amplified signal to the noise removal unit 130.

[0022] The harvest assessment device 100 also has a light source 160. The light source 160 irradiates light toward the harvest target F. The detection unit 110 and the noise-removed signal acquisition unit 120 detect light that is emitted from the light source 160 and transmitted through or reflected by the harvest target F. The detection unit 110 and the noise-removed signal acquisition unit 120 are preferably disposed close to each other.

[0023] The noise removal unit 130 also has a coefficient storage unit 132. The coefficient storage unit 132 stores the relative ratio (coefficient) of the amplification rate of the noise-removed signal and the detection signal when generating a judgment signal by subtracting the noise-removed signal from the detection signal. Here, this relative ratio is generated by calibrating the harvest assessment device 100, for example, when the harvest assessment device 100 is shipped from a factory. This calibration is performed, for example, by analyzing a standard sample with the harvest assessment device 100 while the light source 160 is operating.

[0024] More specifically, a light source, such as a laser light source, that irradiates only light of a wavelength absorbed by a specific component (e.g., sugar) and light in the vicinity thereof is prepared, and light from this light source is incident on the detection unit 110 and the noise-removed signal acquisition unit 120. Then, the relative ratio (coefficient) of the amplification factors of the noise-removed signal and the detection signal is optimized so that the noise-removed signal output by the noise removal unit 130 is maximized. As another calibration method, a light source, such as a laser light source, that has a spectrum other than the wavelength absorbed by a specific component (e.g., sugar) is prepared, and light from this light source is incident on the detection unit 110 and the noise-removed signal acquisition unit 120. Then, the relative ratio (coefficient) of the amplification factors of the noise-removed signal and the detection signal is optimized so that the noise-removed signal output by the noise removal unit 130 is minimized.

[0025] In this embodiment, the light transmitted through the first filter unit 112 also contains a small amount of light outside the first wavelength range. Therefore, the signal generated by the first filter unit 112 also contains components caused by light outside the first wavelength range. In contrast, in this embodiment, the noise-removed signal generated by the noise-removed signal acquisition unit 120 mostly contains components caused by light outside the first wavelength range. Therefore, by using the noise-removed signal acquisition unit 120, it is possible to remove noise components from the detection signal.

[0026] In this embodiment, the detection unit 110 does not necessarily have to include the first filter unit 112.

[0027] Example 2 3 is a diagram showing the configuration of a harvest assessment device 100 according to Example 2. The harvest assessment device 100 according to this example has the same configuration as the harvest assessment device 100 according to Example 1, except that it has an amplifier unit 150 instead of the amplifier units 116 and 126. The amplifier unit 150 is provided between the detector unit 110 and the noise-removed signal acquirer 120.

[0028] While the detection unit 110 is outputting the detection signal to the amplification unit 150, the noise-removed signal acquisition unit 120 does not output the noise-removed signal to the noise removal unit 130 in order to prevent the detection signal and the noise-removed signal from overlapping. Also, while the noise-removed signal acquisition unit 120 is outputting the noise-removed signal to the amplification unit 150, the detection unit 110 does not output the detection signal to the noise removal unit 130 in order to prevent the detection signal from overlapping with the noise-removed signal.

[0029] In this embodiment, the noise removal unit 130 may also function as the amplifier 150. In this case, the noise removal unit 130 has a function of storing the detection signal and the noise-removed signal. The noise removal unit 130 then removes noise from the detection signal by performing the calculation "detection signal - noise-removed signal x coefficient." In this case, the noise removal unit 130 determines the coefficient each time it performs noise removal processing so that the signal in the wavelength region that becomes noise is minimized.

[0030] This embodiment also provides the same effects as those of Embodiment 1. Furthermore, since the detection unit 110 and the noise-removed signal acquisition unit 120 share the amplifier unit 150, noise generated by the amplifier unit 150 is included in both the detection signal and the noise-removed signal. Therefore, the noise removal unit 130 can also remove noise caused by the amplification process from the detection signal by subtracting the noise-removed signal from the detection signal.

[0031] Example 3 4 is a diagram showing the configuration of a harvest assessment apparatus 100 according to Example 3. The harvest assessment apparatus 100 according to this example has the same configuration as the harvest assessment apparatus 100 according to the embodiment, except for the following points.

[0032] First, the harvest assessment device 100 has a light source 160. The configuration of the light source 160 is the same as in the first embodiment. The harvest assessment device 100 also has a history storage unit 134. The history storage unit 134 stores past detection signals from the detection unit 110. The noise-removed signal acquisition unit 120 then reads out the written detection signal from the history storage unit 134 as a noise-removed signal.

[0033] As with Example 2, this Example also makes it possible to remove from the detection signal both noise caused by light outside the first wavelength range and noise caused by the amplification process. Furthermore, the determination signal output by the noise removal unit 130 indicates the amount of variation in a specific component (for example, the amount of increase in sugar content) in the harvest target F. Therefore, when the intensity of the determination signal falls below a reference value, the determination unit 140 can determine that the amount of variation in the specific component in the harvest target F is small and therefore that the harvest target F should be harvested.

[0034] Example 4 5 is a diagram showing the configuration of a harvest assessment apparatus 100 according to Example 4. The harvest assessment apparatus 100 according to this example has the same configuration as the harvest assessment apparatus 100 according to the embodiment, except for the following points.

[0035] First, the harvest assessment device 100 has a light source 160. The configuration of the light source 160 is the same as in the first embodiment. The noise-removed signal acquisition unit 120 generates a noise-removed signal by detecting light from an area that does not include the harvest target F. Here, it is preferable that the area being detected by the noise-removed signal acquisition unit 120 is closer to the harvest target F. This is because the further away from the harvest target F is, the greater the likelihood that noise components not included in the signal detected by the detection unit 110 will be. It is preferable that the noise-removed signal acquisition unit 120 has the second filter unit 122 shown in the first embodiment.

[0036] According to this embodiment, the noise-removed signal is a signal caused by light that has not passed through the harvest target F. In other words, the noise-removed signal contains both components caused by light in the first wavelength range and components caused by light outside the first wavelength range. However, the proportion of the components caused by light in the first wavelength range in the noise-removed signal is greater than the proportion of the components caused by light in the first wavelength range in the detection signal. Therefore, according to this embodiment as well, the noise removal unit 130 can remove noise from the detection signal.

[0037] Example 5 6 is a diagram showing the configuration of a plant growing device 10 according to Example 5. The plant growing device 10 is used in, for example, a plant factory, and includes a harvest determination device 100, an irradiation unit 200, and a classification device 300.

[0038] In the plant growing device 10, a plurality of plants P circulate on a circular conveyor belt. An irradiating unit 200 is provided above the plurality of plants P. The irradiating unit 200 irradiates the plants P with light of a wavelength suitable for the growth of the plants P. Here, the irradiating unit 200 may change the wavelength of the light in accordance with the growth stage of the plants P.

[0039] Identification information that identifies each of the multiple plants P is assigned to each plant P. This identification information is stored, for example, in an IC chip attached to the growth container of the plant P. The harvest assessment device 100 then determines the harvest timing of the harvest target F that the plant P possesses. At this time, the harvest assessment device 100 reads the identification information of the plant P that possesses the harvest target F that is the inspection target from the IC chip. The harvest assessment device 100 then outputs the identification information corresponding to the harvest target F that has been determined to be harvested to the classification device 300. The harvest assessment device 100 has a configuration similar to that of any of the embodiment or Examples 1 to 4.

[0040] The sorting device 300 is provided on a part of the belt conveyor, and reads the identification information of the plant P passing through the sorting device 300 from the IC chip. When the read identification information matches the identification information received from the harvest assessment device 100, the sorting device 300 moves the plant P to a route separate from the circular belt conveyor so that the harvest target F can be harvested.

[0041] According to this embodiment as well, the timing to harvest the harvest target object F can be determined with high accuracy.

[0042] Although the embodiments and examples have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted. [Explanation of symbols]

[0043] 10 Plant growing equipment 100 Harvest Judgment Device 110 Detector 112 First filter section 114 First photoelectric conversion unit 120 Noise removal signal acquisition unit 122 Second filter section 124 Second photoelectric conversion unit 130 Noise removal section 132 Coefficient memory unit 134 History memory unit 140 Judgment Department

Claims

[Claim 1] a detection unit that detects detection light transmitted through or reflected from the harvest object and generates a detection signal; a noise-removed signal acquisition unit that acquires a noise-removed signal included in the detection signal; a noise removal unit that uses the detection signal and the noise-removed signal to generate a judgment signal, which is the detection signal after noise removal; a determination unit that determines the harvest timing of the harvest target object based on the determination signal; A harvest determination device equipped with:

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