Agricultural harvester and method for determining at least one characteristic of harvested crop

Abstract

The invention relates to an agricultural harvester comprising a harvesting attachment having a harvesting and feeding device for cutting and picking up a crop wherein a measuring device is provided for determining at least one characteristic of the crop; the present invention relates to an agricultural harvester, and to a method for determining at least one characteristic of a crop, where the crop is harvested using an agricultural harvester comprising a harvesting attachment, where the harvesting attachment comprises a harvesting and feeding device by which the crop is cut and picked.

Description

[0001] Description

[0002] The present application relates to an agricultural harvester with a harvesting attachment having a harvesting and feeding device for cutting and picking up a harvested crop, wherein a measuring device for determining at least one property of the harvested crop is provided; and a method for determining at least one property of a harvested crop, wherein the harvested crop is harvested using an agricultural harvester with a harvesting attachment having a harvesting and feeding device by which the harvested crop is cut and picked up.

[0003] It is known to analyze certain properties of a harvested crop during harvesting. EP3130213A1 relates to a measuring device for a combine harvester for examining a harvested grain, comprising a measuring chamber having an inlet and an outlet for a sample of the harvested grain to be examined, wherein the measuring chamber is designed such that during operation the sample enters the measuring chamber from the inlet in a flow direction and from the measuring chamber into the outlet. A transmission spectrometer is provided, which has a first element in the form of a light source and a second element with a transducer for light generated by the light source and transmitted through the sample. The transducer is connected to an analyzer for analyzing the received light in a wavelength-resolved manner.

[0004] DE102011051784A1 discloses a method of operating a harvester with an optical sensor, using which the treated surface directly behind the attachment is optically detected in order to obtain conclusions about the condition of the treated surface. Cameras sensitive in the near infrared (NIR) are indicated as particularly suitable, since such cameras offer additional possibilities for analyzing plant residues and the ground. For example, the moisture content of the soil and / or plant residues can be determined.

[0005] The use of NIR cameras in areas where daylight is present has the disadvantage that the NIR component of sunlight influences the measurement results, wherein this influence depends on the time of day, the season and the weather.

[0006] It is an object of the present application to propose an agricultural harvester which avoids the disadvantages of the prior art.

[0007] This object is achieved by the subject matter of claim 1. The object is further achieved by the method according to claim 7. Embodiments are seen from the dependent claims.

[0008] The agricultural harvester has a harvesting attachment with a harvesting and feeding device for cutting and picking up the crop. A measuring device for determining at least one property of the harvested crop is provided, wherein the measuring device has at least one optical detection unit which is arranged on the harvester behind the harvesting attachment and wherein the optical detection unit detects radiation reflected from plant residues left in the ground.

[0009] The detection of the reflected radiation of the plant residues left in the ground has the advantage that properties of the crop at the lower part of the plants can be determined and the growth situation can also be taken into account in the determination. The determination of properties of the crop at the lower part of the plants, i.e. at the level at which the crop is cut, has the advantage that, inter alia, the straw moisture can be determined as a property of the crop. The straw moisture is a key plant physiological property which is particularly important for the cut crop. Thus, the determination of the straw brittleness provides a particularly advantageous possibility for controlling the harvesting device depending on the straw brittleness determined immediately after the cut crop. This type of control is particularly advantageous in the case of uneven crop maturity. The straw brittleness is also an important parameter for the feeding device and for the threshing mechanism and the straw chopper of the harvester, so that these components can also be advantageously controlled depending on the determined straw brittleness.

[0010] A further advantage of the solution is that the non-cereal components are examined at the cutting height. The plants can be very dry in the upper region and very moist and thus tough in the lower third. The growth is only a few centimeters above the cutting height. The properties of the plant parts in the lower third of the growth height are often ignored when determining the properties of the entire crop flow. However, these properties of the plants often have a considerable influence on the threshing properties and the grain quality. In practice, it is often said that "an increase in the cutting height by ten centimeters reduces the grain moisture by a maximum of 1%", which is not scientifically proven and certainly not accurate in dry, easily threshable crops. In addition, tough straw impairs the threshing properties and ultimately also the machine performance. Therefore, especially in difficult harvesting conditions, it can be advantageous to carefully observe the crop at the cutting height and to adjust the threshing mechanism and the cutterbar depending on these parameters, for example to raise the harvesting attachment in the presence of weeds or volunteer plants.

[0011] In particular, the agricultural harvester has a harvesting attachment whose harvesting and feeding device cuts the crop and collects the crop immediately thereafter. In particular, it is not a so-called swath mower which spreads the cut crop for later collection. The term radiation is to be understood as meaning electromagnetic radiation, in particular light, at least including the wavelength spectrum of sunlight, including visible light, ultraviolet radiation and infrared radiation.

[0012] According to one embodiment, the detection unit is arranged on the ground-facing underside of the harvester. In particular, the detection unit can be arranged in the region of the front axle of the harvester, i.e. between the drive wheels of the harvester.

[0013] According to a further embodiment, the detection unit is aligned obliquely with respect to the ground, in particular at an angle of between 35 degrees and 55 degrees, preferably at an angle of approximately 45 degrees. In particular, the detection unit is aligned in such a way that as much light as possible reflected from the plant residues and as little light as possible reflected from the ground reaches the detection unit. The ground spectrum interferes with the measurement. An oblique arrangement with respect to the ground, for example at an angle of 45 degrees to the ground, is particularly advantageous. The reflected light falls into the detection unit along the detection axis in a straight line and then, for example, forms an angle of 45 degrees to the ground. At steeper angles of more than 55 degrees, for example, more light reflected from the ground reaches the detection unit. At shallower angles of less than 35 degrees, for example, only light reflected from the upper part of the plant residues and from more distant plant residues reaches the detection unit. Preferably, however, the plant residues are detected over as much of their length as possible and in the immediate vicinity of the detection unit.

[0014] The detection unit has a light source to illuminate the plant residues left in the ground. This makes the detection of the reflected radiation advantageously independent of natural lighting conditions. The detection unit has a spectrometer which detects the intensity of the radiation of the reflected radiation from the plant residues left in the ground in a wavelength-resolved manner. This means that the intensity of the radiation is recorded via the detected spectrum. The spectrometer can be, for example, an optical spectrometer in which the wavelengths of the reflected light to be analysed are distinguished, for example, by means of a directional deflection by refraction in a prism or by diffraction at a grating. Alternatively, it is also possible to determine the frequency components by using an interferometer of a Fourier analysis (FTIR spectrometer). In a further embodiment, a spectrometer based on a photodiode array can be used. The latter has several semiconductor diodes which respond to individual wavelengths. The resolution is sufficient for this purpose and this design is significantly cheaper than the previously mentioned spectrometer.

[0015] According to another embodiment, an evaluation unit may be provided to evaluate the spectrum of detected light, from which at least one characteristic of the crop stream can be derived. The evaluation unit may have a computer and may be connected to a detection unit via a signal line for transmitting measurement signals. The spectrum may be in the visible wavelength range and / or in the near-infrared range, specifically having wavelengths between 400 nm and 2200 nm. Up to 900 nm, color characteristics and chlorophyll content can be advantageously determined. Between 1000 nm and 2200 nm, interactions leading to plant state occur through substances such as cellulose, lignin, and water. In particular, the characteristic of the crop stream to be determined is straw brittleness, which depends on the maturity of the crop in the stream. This can be advantageously determined using methods comparable to vegetation indices (i.e., characteristic values ​​representing vegetation analysis). Certain radiation characteristics of plants are used to distinguish them from non-vegetation areas because plant chlorophyll primarily absorbs visible light in the blue and red frequency ranges. In the near-infrared range, there exists a region with wavelengths between 700 nm and 900 nm, where light is particularly strongly reflected by the intact cellular structure of the plant. This principle can be applied to harvested crops, even when the differences in radiation characteristics between different crop maturity levels are small. Maturity can be derived from the plant's cell structure and remaining chlorophyll content.

[0016] Vegetation indices are determined, for example, by at least one ratio of reflectance values ​​across different spectral ranges, particularly the sum ratio and / or difference ratio of reflectance values ​​across different spectral ranges. For example, vegetation indices are designed as NDVI (Normalized Differential Vegetation Index). Specifically, using a computer in an evaluation unit, the vegetation index, forming NDVI, is calculated as the quotient of the difference between reflectance values ​​in the near-infrared range of the electromagnetic spectrum (RNIR) and the reflectance values ​​in the red visible range of the electromagnetic spectrum, and the sum of the reflectance values ​​in the near-infrared range of the electromagnetic spectrum (RNIR) and the reflectance values ​​in the red visible range of the electromagnetic spectrum. When crops are mature and ready for harvest, using the frequency band in the blue visible range of the electromagnetic spectrum (RBlue) has proven advantageous. Furthermore, the received signal is processed and edited before calculating the index to obtain better results. However, in the red visible range of the electromagnetic spectrum, a high proportion of green growth can be better assessed if the chlorophyll content remains correspondingly high. Specifically, there are formulas for calculating vegetation indices in the form of modified NDVI:

[0017] NDVI=(RNIR - RBlue) / (RNIR + RBlue).

[0018] This results in values ​​between -1 and +1, with negative values, for example, when radiating water surfaces, being irrelevant in this application. The closer the positive exponent value is to zero, the greater the degree of crop maturity. The reflectance value R is a value between 0 and 1 and represents how much light is reflected from a surface at a specific wavelength. In the modified NDVI formula, the reflectance value RNIR in NIR and Rblue in the blue range are used to assess the degree of crop maturity.

[0019] The spectrometer is configured to detect the intensity of at least one calibration wavelength range, wherein the calibration wavelength range is outside the wavelength spectrum emitted by the light source, and wherein the calibration wavelength range is within the wavelength spectrum of sunlight. The evaluation unit can be configured to determine crop characteristics based on the development of this radiation intensity within the calibration wavelength range. This is an advantageous way to determine the intensity of sunlight affecting the detection. The calibration wavelength range is advantageously selected such that the reflectance characteristics of stubble and ground are as independent as possible from crop maturity, humidity, and green growth within its spectral range. Bands from the UV range are examples of available calibration wavelength ranges. If the spectrometer is exposed to more or less strong solar radiation, this can be recorded by measuring the intensity of the calibration wavelength range. In the evaluation unit, it can then be distinguished whether the variation in light intensity within the spectral range to be evaluated is caused by a change in crop characteristics or by other lighting conditions.

[0020] According to another embodiment, the detection unit may have a housing with a transparent cover. The spectrometer, and (if applicable) the illumination, is advantageously protected from external influences within the housing. The transparent cover may be, for example, a safety glass plate, wherein the safety glass has an impact resistance of at least 80 MPa, particularly between 120 MPa and 200 MPa, in a pendulum impact test according to DIN EN 12600. This safety glass is advantageously scratch-resistant and may be, for example, borosilicate glass, aluminosilicate glass, heat-toughened soda-lime glass, or chemically toughened glass. The reflected radiation advantageously passes through the transparent cover to reach the spectrometer. A cleaning device may be provided to remove contaminants from the outer surface of the transparent cover.

[0021] According to another embodiment, the detection unit may have a calibration light source, wherein a beam of light from the calibration light source is directed onto the transparent cover in such a way that a portion of the beam reflected by the cover strikes a light receiver. The calibration light source is arranged inside the housing such that the beam strikes the interior of the transparent cover. The light receiver may be integrated into the spectrometer or arranged separately from the spectrometer within the housing. In particular, the light receiver is designed such that reflections of the beam from outside the housing do not enter the light receiver. As the transparent cover becomes dirty, the amount of reflection through the transparent cover increases, and the light receiver measures the increased intensity. Advantageously, this information can be used to correct for determined characteristics of the crop and / or trigger cleaning of the transparent cover.

[0022] According to another embodiment, controls for at least one component of the harvester can be configured to control the component based on at least one characteristic of the crop being harvested, wherein the component includes a harvesting attachment, a conveyor, a threshing mechanism, a traction drive, and a straw shredder. The travel speed can be controlled via the traction drive to adapt the throughput to the crop being harvested.

[0023] Another aspect for achieving the aforementioned objective relates to a method for determining at least one characteristic of a harvested crop, wherein the harvested crop is harvested using an agricultural harvester with a harvesting attachment having a harvesting and feeding device, by which the harvested crop is cut and picked up. After the crop is cut, radiation reflected from plant residue left on the ground is detected by at least one optical detection unit.

[0024] According to one embodiment, the spectrum of the detected light is evaluated, wherein at least one characteristic of the material is derived from the spectrum. Plant residue left on the ground can be illuminated with a light source.

[0025] The intensity of at least one calibration wavelength range is detected, wherein the calibration wavelength range is outside the wavelength spectrum emitted by the light source, and wherein the calibration wavelength range is within the wavelength spectrum of sunlight. Crop characteristics can be determined based on the development of radiation intensity within the calibration wavelength range. The calibration wavelength range is advantageously selected such that the reflectance characteristics of stubble and ground are as independent as possible from crop maturity, humidity, and green growth within its spectral range. Bands from the UV range are examples of available calibration wavelength ranges. If the spectrometer is exposed to more or less strong solar radiation, this can be recorded by measuring the intensity of the calibration wavelength range. In the evaluation unit, it can then be distinguished whether the variation in light intensity in the spectral range to be evaluated is caused by changes in crop characteristics or by other lighting conditions.

[0026] According to another embodiment, a beam of light from a calibration light source of the detection unit is guided onto the transparent cover of the detection unit in such a way that a portion of the beam reflected by the cover strikes a light receiver. The intensity of the reflected portion of the beam can be used to draw conclusions about the degree of contamination of the transparent cover. Specifically, the light receiver is designed so that reflections of the beam from outside the housing do not enter the light receiver. In particular, the beam can be pulsed to create a difference between reflected radiation from outside the detection device and the portion of the beam reflected by the transparent cover plus reflected radiation from outside the sensor. The measure of contamination of the transparent cover can be derived from this difference. The spectral range of the beam of the calibration light source can be within the range of the spectrometer or in a spectral range independent of it. If the light receiver and the spectrometer use the same wavelength and / or the same mounting space, the spectral values ​​of the residue can be measured, especially during pulse pauses.

[0027] Another aspect of this application relates to a method for controlling at least one component of a harvester, wherein at least one characteristic of the crop is determined according to the method described above, and wherein the component is controlled based on the at least one characteristic of the crop material. Each component includes at least a harvesting attachment, a conveyor, a threshing mechanism, a traction drive, and a straw shredder.

[0028] The invention will now be described in more detail with reference to the accompanying drawings. These explanations also apply to the described agricultural harvester and method. In the drawings:

[0029] Figure 1 A schematic diagram showing an example of an agricultural harvester;

[0030] Figure 2 Detailed illustration Figure 1 A schematic diagram of the measuring device.

[0031] Figure 1 An example of a combine harvester as an agricultural harvester is shown, having a harvesting attachment 14 articulated to the front of the combine harvester frame in the direction of travel, and an inclined conveyor 9 through which the harvested crop material reaches the threshing mechanism 10. The frame has front drive wheels 1 and a rear axle with steering wheels 2. The cab 3 is located on the frame in the area in front of the drive wheels 1. Directly behind it is a grain storage tank 4, followed by a drive motor 5. At the rear of the combine harvester are a straw shredder 16 and an outlet 7 for the crop portion separated from the grain as an indigestible part. A vibrating screen 11 is designed to slope from the center area of ​​the combine harvester toward the rear.

[0032] The harvesting attachment 14 has a harvesting and feeding device for cutting and picking up crops. A measuring device is provided for determining at least one characteristic of the harvested crop, wherein the measuring device has at least one optical detection unit 12 arranged on the harvester, behind the harvesting attachment 14, and wherein the optical detection unit 12 detects radiation 8 reflected from plant stubble 6 left on the ground after the crop has been cut. As in this exemplary embodiment, the detection unit 12 can be arranged on the ground-facing lower side 15 of the harvester, in the area between the drive wheels 1 of the front axle of the harvester.

[0033] An evaluation unit 20 is provided to evaluate the spectrum of the detected light, wherein straw brittleness can be derived from the spectrum as at least one characteristic of the harvested crop. The evaluation unit can be arranged at the mounting location of the detection unit 12. In the exemplary embodiment shown, the evaluation unit 20 is arranged in the cab 3 and receives measurement signals from the detection unit 12 via a signal connection (not shown), which can be wired, wireless, or via fiber optic. A control 19 for at least one component of the harvester is configured to control the component according to the straw viscosity of the harvested crop, wherein the control 19 receives information from the evaluation unit 20 via another signal connection (not depicted). The component controlled by the control 19 according to straw brittleness can be the harvesting attachment 14, the conveyor 21, the threshing mechanism 10, and the straw shredder 16.

[0034] As a detail of the detection unit (12), Figure 2 Showing from Figure 1 A schematic view of the measuring apparatus. To illuminate the plant residue 6 left on the ground, the detection unit 12 has two light sources 22. Radiation 8 reflected by the plant residue 6 reaches a spectrometer 18 via a lens 23, which detects the intensity of the broadband radiation 8 reflected by the plant residue 6 in a wavelength-resolution manner. The spectrometer 18 is further arranged to detect the intensity of at least one calibration wavelength range, which is outside the wavelength spectrum emitted by the light sources 22 and is within the wavelength spectrum of sunlight. The evaluation unit 20 determines crop characteristics based on the development of radiation intensity within the calibration wavelength range to compensate for the influence of sunlight on the measurement.

[0035] The detection unit 12 has a housing 28 with a transparent cover 17. The transparent cover 17 may be a glass plate made of scratch-resistant safety glass. An additional calibration light source 24 is provided in the housing 28, wherein the beam 25 of the calibration light source 24 is guided onto the transparent cover 17 in such a way that a portion 26 of the beam 25 reflected by the transparent cover 17 strikes a light receiver (27). The degree of contamination of the transparent cover 17 is derived from the intensity of the reflected portion 26 of the beam 25.

[0036] The detection unit 12 is tilted relative to the ground, specifically aligned in such a way that as much light as possible is reflected from the plant debris 6 and as little light as possible is reflected from the ground reaches the detection unit 12. Ground spectral interference measurement. The tilted arrangement relative to the ground (e.g., at an angle α of 45 degrees to the ground) is particularly advantageous. The detection axis E through which the light (8) directly enters the detection unit 12 is at an angle α of, for example, 45 degrees to the ground.

[0037] List of reference numerals

[0038]

Claims

1. An agricultural harvester with harvesting attachments, characterized in that, The harvesting attachment includes a harvesting and feeding device for cutting and picking up the harvested crop. The measuring device is provided to determine at least one characteristic of the harvested crop. The measuring device has at least one optical detection unit (12) arranged on the harvester, behind the harvesting attachment, and wherein the optical detection unit detects radiation (8) reflected from plant stubble left on the ground. The detection unit (12) has at least one light source (22) for illuminating the plant debris (6) left on the ground, and the detection unit (12) has a spectrometer (18) for detecting the intensity of radiation reflected from the plant debris left on the ground in a wavelength resolution manner. The spectrometer (18) is adapted to detect the intensity of at least one calibration wavelength range, wherein the calibration wavelength range is outside the wavelength spectrum emitted by the light source (22) and wherein the calibration wavelength range is within the wavelength spectrum of sunlight.

2. The agricultural harvester as described in claim 1, characterized in that, The detection unit is arranged on the ground-facing underside of the harvester, particularly in a portion of the harvester's front axle.

3. The agricultural harvester as described in claim 1 or 2, characterized in that, The detection unit (12) is oriented at an angle relative to the ground, particularly at an angle (α) between 35 and 55 degrees.

4. The agricultural harvester as described in claim 1 or 2, characterized in that, An evaluation unit (20) is provided to evaluate the spectrum of the detected radiation (8), wherein at least one characteristic of the harvested crop can be derived from the spectrum, wherein controls (19) of at least one component of the harvester are configured to control the component according to the at least one characteristic of the harvested crop, wherein the component includes the harvesting attachment (14), conveyor (21), threshing mechanism (10), straw shredder (16) and traction drive.

5. The agricultural harvester as described in claim 4, characterized in that, The evaluation unit (20) is adapted to determine the characteristics of the crop based on the development of the intensity of the radiation within the calibrated wavelength range.

6. The agricultural harvester as described in claim 1 or 2, characterized in that, The detection unit has a housing (28) with a transparent cover (17) and a calibration light source (24), wherein the light beam (25) of the calibration light source is guided onto the cover (17) in such a way that a portion (26) of the light beam reflected by the cover strikes a light receiver (27).

7. A method for determining at least one characteristic of a harvested crop, characterized in that, The harvested crop is harvested using an agricultural harvester equipped with a harvesting attachment (14), wherein the harvesting attachment has a harvesting and feeding device, and the harvested crop is cut and collected using the harvesting and feeding device. After the harvested crop is cut, at least one optical detection unit (12) is used to detect the radiation (8) reflected from the plant residue (6) left on the ground. The plant debris (6) left on the ground is illuminated by a light source (22), wherein the intensity of at least one calibration wavelength range is detected, wherein the calibration wavelength range is outside the wavelength spectrum emitted by the light source and wherein the calibration wavelength range is within the wavelength spectrum of sunlight.

8. The method as described in claim 7, characterized in that, The spectrum of the detected radiation (8) is evaluated, wherein the at least one characteristic of the crop is derived from the spectrum.

9. The method as described in any one of claims 7 or 8, characterized in that, The characteristics of the crop are determined based on the development of the intensity of the radiation within the calibrated wavelength range.

10. The method as claimed in claim 7 or 8, characterized in that, The beam (25) of the calibration light source (24) of the detection unit (12) is guided onto the transparent cover (17) of the detection unit (12) in such a way that a portion (26) of the beam reflected by the cover strikes the light receiver (27).

11. The method as described in claim 10, characterized in that, The intensity of the reflective portion (26) of the beam (25) is used to determine the degree of contamination of the transparent cover (17).

12. A method for controlling at least one component of a harvester, characterized in that, The method according to any one of claims 7 or 8 determines at least one characteristic of the crop, and wherein the component is controlled depending on the at least one characteristic of the crop material.

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