Patent Description:
For example, the possibility of measuring in real time the protein trend in the harvest gathered and the geolocation of the measured values is an important input datum for evaluating the optimum prescription map in terms of fertilizers.

Today, basically two classes of instruments are known that are able to evaluate in real time the quality of the crop that is being harvested:.

Although the spectrophotometers offer good efficacy in the analysis of the harvest, they have some practical drawbacks.

First of all, as said, they are rather costly, and this has certainly limited the diffusion thereof on the market.

Further, the spectrophotometers are sensitive to the operating temperature and use thereof is limited to applications characterized by operating temperatures up to <NUM>/<NUM>. In the field of harvesting machines, some are characterized by operating temperatures that sometimes exceed <NUM>° Celsius. Such operating temperatures in fact prevent analysers from being implemented that are based on a spectrophotometer, thus excluding the possibility of a real-time and geolocated measurement of the nutritional parameters by means of a spectrophotometer analyser.

<CIT> discloses a device for analyzing the crop, which can be mounted on an agricultural machine, equipped with a case within which a light source and a plurality of detectors are arranged so as to perform an analysis of the crop. The detectors can be set up for an analysis based on a specific wavelength range.

The technical task underlying the present invention is thus to propose an apparatus that is able to measure the nutritional profile of the crop by overcoming the aforesaid drawbacks.

This technical task is attained by the apparatus made according to claim <NUM>. Further characteristics and advantages of the present invention will become more apparent from the following indicative, and hence non-limiting, description of a preferred, but not exclusive, embodiment of the apparatus according to the invention, as illustrated in the accompanying drawings, in which:.

With reference to the cited figures, with <NUM> an apparatus has been indicated for the analysis of the agricultural product during the harvesting step, made in accordance with the invention.

The proposed apparatus <NUM> is specially intended to be fitted to self-propelled agricultural machines like threshers, choppers, forage-collecting wagons, balers,. in positions that are a function of the application, but in each case are such as to permit wide sampling of the crop directly on line and on the harvesting machine.

At the practical level, the analysis apparatus <NUM> of the invention is designed to be "hit" directly by the flow of crop cut and loaded onto the machine to which it is fitted in order to measure in real time the nutritional content of the crop.

In the preferential embodiment shown in the attached figures, the apparatus <NUM> includes a protective casing <NUM>, for example of polyhedral shape, which completely contains the active components of the invention that are intended to analyse the composition of the harvest.

The casing <NUM> comprises completely opaque outer walls and a bottom, or anyway an end, which is still opaque but provided with an opening <NUM>, which is instead closed by at least one transparent element <NUM>, <NUM>, preferably made of glass, that enables the light to enter/exit the casing <NUM>.

In the embodiment shown, the invention includes two completely transparent glass elements <NUM>, <NUM> that are parallel to one another, one of which is external that is affected directly by the harvest flow and one of which is internal, protected by the former.

In this manner, if the outer transparent glass element <NUM> was to be smashed by stones or other objects that are foreign to the harvest that are projected at speed against it, the presence of the inner glass element <NUM> avoids the risk that those or further small objects enter the casing <NUM> and hit the aforesaid active elements, damaging them.

The active elements of the invention comprise above all a light source <NUM>, for example a lamp, for sending light radiation to the crop, directed to the opening <NUM> of the casing <NUM>.

Further, the proposed apparatus <NUM> includes, protected in the casing <NUM>, a plurality of sensors <NUM> for acquiring light radiation reflected by the crop and then passed through the aforesaid opening <NUM> and a plurality of filtering elements <NUM> that are adapted to permit the complete passage only of light provided with frequencies comprised in a predetermined passband (see <FIG>).

According to an important aspect of the invention, the filtering elements <NUM> have passbands that are different from one another and each filtering element is functionally coupled with a respective sensor <NUM>, such that the latter receives only light radiation that has traversed the former.

In practice, the invention provides a plurality of optical sensors <NUM>, preferably of digital type, opposite which, preferably in close proximity, a specific optical filter <NUM>, or another filtering element <NUM> having the properties illustrated above is placed which has a passband that is different from the passboard of the other filters <NUM>, so that each sensor <NUM> receives only that part of light reflected by the crop that has frequencies comprised in that passband.

Before illustrating further significant aspects of the invention, one of the important underlying concepts of the invention is explained.

The spectrophotometers are characterized by:.

These metrological characteristics of the spectrophotometer enable predictions to be obtained of the content of the analysed crop that are extremely accurate. In fact, owing to the Lambert-Beer law (which shows direct proportionality between the absorption of the reflected light and the concentration of the solution), it is possible to define models that are able to predict extremely accurately the content of the different nutrients in the sample. The invention on the other hand makes available a plurality of light sensors <NUM>, each of which can acquire light energy only from light characterized by a limited spectral range; frequencies/wavelengths comprised in a specific passband.

For example, each characteristic passband may have an amplitude comprised between <NUM> and <NUM> and the intensity value supplied by the sensor is equivalent to all the light energy affecting the specific sensor.

In practice, the different passbands are predetermined and are the significant passbands in function of one or more nutrients that have to be measured inasmuch as they are present in the crop and are important for the quality of the sample like, by way of non-limiting example, water, protein, starch, neutral cleaned fibres, acid cleaned fibres, ashes, greases, etc..

Accordingly, when the radiation emitted by the light source of the proposed apparatus <NUM> is reflected by the crop sample opposite the transparent wall <NUM>, it will reach all the filtering elements <NUM>, each of which will only let radiation pass through completely that has frequencies comprised in the characteristic passband of the filtering element <NUM>.

After this, a processing unit <NUM> of the apparatus <NUM>, to which all the sensors <NUM> and the source <NUM> are connected and which is preferably completely contained in the casing <NUM>, will collect the intensity value of the light acquired by the various sensors <NUM>, thereby determining a quantitative measurement of the specific parameters of the harvest that the sensors <NUM> are supposed to predict.

The processing unit <NUM> comprises a software or hardware analysis module configured to determine at least one quantitative parameter, whether evaluated as such or on the dry substance, relatively to the agricultural crop analysed, in accordance with the intensity of the light signals acquired by all the sensors <NUM> hit by reflected light from the samples analysed for that harvest.

In detail, this analysis module is configured to measure the light intensity of the reflected light in the different spectral ranges, measure the absorption thereof, maximize the noise signal ratio through appropriate algorithms and, lastly, obtain the best estimate for the parameter/s by applying the prediction model/s appropriately determined in accordance with the Lambert-Beer law. As shown in <FIG> and <FIG>, the apparatus <NUM> includes, completely contained in the casing <NUM>, a support body <NUM>, preferably with the shape of a bell or upturned vase, provided with one or more side walls in which the sensors <NUM> are fixed.

The walls of the support body <NUM> define an inner volume V, having a summit (or at least one end) from which the light source <NUM> emits light radiation. The support body <NUM> is fitted inside the casing <NUM>, so that the light source and the sensors <NUM> fixed thereto face the opening of the bottom of the casing <NUM> (see again <FIG>).

In practice, the support body <NUM> has a flared shape and comprises a main opening <NUM>, in a position opposite the light source <NUM>, the main opening of which faces the opening <NUM> of the casing <NUM> (see <FIG>).

In the embodiment shown, the main opening <NUM> of the body <NUM> and that of the casing <NUM> are in close proximity and, in particular, the edge of the main opening <NUM> is in contact with or near the inner surface of the bottom of the casing <NUM>, so that the opening of the body <NUM> faces the inner glass element <NUM> directly (if present, or at least faces the aforesaid transparent closing element <NUM>, <NUM>), obtaining the result that most of the light reflected by the crop and passing through the opening <NUM> of the casing <NUM> traverses the inner volume V of the body <NUM> and then reaches the filters <NUM> and the corresponding sensors <NUM>.

In the side wall of the support body <NUM> oblique through holes <NUM> are obtained, into which respective sensors <NUM> are inserted so as to face the main opening <NUM> and so oriented to maximize the area of the surface "seen" by all the sensors <NUM>; at each hole <NUM> a filtering element <NUM> is arranged, preferably in close proximity to the head of the sensor <NUM> intended to receive the light to be analysed.

The term "oblique", in the preceding paragraph, must be understood with reference to the central axis of the body <NUM> that passes through the light source <NUM> or the plane on which the edge of the main opening <NUM> lies.

The holes <NUM> of the support body <NUM> can have an inner thread provided for engaging with an outer thread with which the sensors <NUM> are provided, so as to ensure both solid fixing and precise positioning of the sensors <NUM>.

One important aspect of the invention is the fact that all the sensors <NUM> are arranged at the same distance from a central point of the main opening <NUM>. In detail, if the main opening <NUM> is circular, as preferable, the through holes <NUM> in which the sensors <NUM> are located are all that the same identical distance from the geometric centre of the circumference of the opening <NUM>. Preferably, these holes <NUM> are placed on the same circumference; even more in detail, this circumference is parallel to the circumference of the main opening <NUM> and thus both have the centre on the same axis, which is the central axis of the body <NUM>.

For this reason, the support body <NUM> is preferably provided with a circular section at which the holes <NUM> are obtained.

In this manner, it is obtained that the Euclidean distance between the centre of the filament of the light source, the circular opening <NUM> and each of the sensors <NUM> is exactly the same. The angle of inclination of the sensors with respect to the support axis <NUM> and the corresponding angle between two consecutive sensors <NUM> will be such as to maximize the intersection between the surfaces scanned by the different sensors. The light reflected by the fraction of sample inside the aforesaid intersection is such as to permit, at any instant, the different spectral information on the same physical sample to be acquired.

The aforesaid holes <NUM> are arranged at constant or variable angular distances and can be of a number between <NUM> and <NUM>, like for example <NUM>.

It should be noted that, in a possible embodiment in which no support body <NUM> made like the one disclosed above is present, in each case the sensors <NUM> would be placed at the same distance from the centre of the opening <NUM> of the casing <NUM> and be distributed in accordance with the conditions set out above.

According to a further important aspect of the invention, the apparatus <NUM> comprises a reflective calibration element <NUM>, preferably of the high reflection type (for example greater than <NUM>%) that is movable between one position of use in which it is active, being illuminated by the light source <NUM> (shown in <FIG>, <FIG> and <FIG>) and reflecting the light towards the sensors <NUM> and a rest position (shown in <FIG> and <FIG>) in which it disappears from the lighted field.

For example, the calibration element can be a white ceramic block <NUM>, characterized by great stability both over time and in temperature.

In any case, the apparatus <NUM> preferably includes a support element <NUM>, for example a plate, on which the calibration element <NUM> is fixed and which is hinged on a side wall of the support body <NUM>, so as to be able to move the calibration element <NUM> between the position of use in which it is between the inner volume V and the rest position, in which it does not reflect light to the sensors <NUM>.

In the embodiment shown, the support body <NUM> is provided with a second opening <NUM>, obtained on the side wall, at or near an edge of which the hinge of the support element <NUM> is applied, such that it can be arranged in the opening <NUM>, with the calibration element <NUM> that faces the outside of the body <NUM>, which constitutes the rest position thereof in which it is distanced from the inner volume V of the body <NUM>.

When the support element <NUM> takes the calibration element <NUM> to the position of use, it is substantially in the plane of the main opening <NUM> and located centrally thereto, so that the light produced by the source <NUM> hits the reflective surface of the calibration element <NUM> and is reflected towards the sensors <NUM>, which it reaches simultaneously.

The reason for introducing the internal calibration element is to permit self-calibration of the fast device so as to minimize the impact of the changes of the environmental conditions on the light signal acquired by the sensors <NUM>. Advantageously, the invention provides a single reference consisting of the calibration element <NUM>, the characteristics of which in a predetermined luminosity condition are known and stored in a memory module of the processing unit <NUM>, the calibration element <NUM> of which is periodically taken to the use position so that it is lighted by the source <NUM> and the reflected light is acquired by all the sensors <NUM>.

At this point, the processing unit <NUM>, having available in the memory module the intensity values of the reflected light (IR) in the different passbands in the known reference conditions (the "dark" intensity values (ID) (equivalent to the noise acquired by the sensors <NUM> in the absence of light dispensed by the source), and the intensity values measured in current operating conditions (IC), is able to calculate absorption for the acquired signal by reading the reflected light of the harvest examined in current work conditions at each sensor <NUM>: <MAT>.

In practice, the apparatus <NUM> comprises a motor that rotates the support element <NUM> of the ceramic block <NUM>, or another calibration element, the motor of which is controlled by the processing unit <NUM> so as to take the block <NUM> to the use position at predetermined intervals, in each case cyclically and in a programmed manner, so as to perform calibration at a frequency that is such as to ensure the reliability of the acquired values.

In general, it should be noted that, in the present description, the processing unit <NUM> has been presented as being subdivided into distinct functional units for the sole purpose of describing the functions thereof in a clear and complete manner.

In practice, this processing unit <NUM> can consist of a single electronic device that is suitably programmed to perform the disclosed functions; the different modules can correspond to hardware entities and/or to routine software that are part of the programmed device.

Alternatively or additionally, these functions can be performed by a plurality of electronic devices on which the aforesaid functional modules can be distributed.

In general, the processing unit <NUM> can use one or more microprocessors or microcontrollers for running the instructions contained in the memory modules.

Claim 1:
An apparatus (<NUM>) for agricultural crop analysis, said apparatus (<NUM>) comprising a light source (<NUM>) for sending light radiation towards a crop, and characterized in that it further comprises a plurality of sensors (<NUM>) for the acquisition of light radiation reflected by said crop and a plurality of filtering elements (<NUM>) adapted to enable complete passage only of light having frequencies within a predetermined passband, wherein said filtering elements (<NUM>) have passbands that differ from each other and wherein each filtering element (<NUM>) is functionally coupled to a respective sensor (<NUM>) so that the sensor (<NUM>) receives only light radiation that has passed through the filtering element (<NUM>); wherein the different passbands of the filtering elements are predetermined and are the significant passbands in function of one or more of the following nutrients present in the crop:
water, protein, starch, neutral cleaned fibres, acid cleaned fibres, ashes, and / or greases;
wherein the apparatus (<NUM>) includes a processing unit (<NUM>), to which all the sensors (<NUM>) and the source (<NUM>) are connected, able to collect an intensity value of the light acquired by the various sensors (<NUM>),
thereby determining a quantitative measurement of the specific parameters of the harvest that the sensors (<NUM>) are supposed to predict;
wherein the processing unit (<NUM>) comprises a software or hardware analysis module configured to determine at least one quantitative parameter, whether evaluated as such or on the dry substance,
relatively to the agricultural crop analysed, in accordance with the intensity of the light signals acquired by all the sensors (<NUM>) hit by reflected light from the samples analysed for that harvest;
wherein the apparatus comprises a support body (<NUM>) provided with one or more side walls in which the sensors (<NUM>) are fixed, said one or more side walls defining an internal volume (V) having a top from which the light source (<NUM>) emits light radiation;
wherein the sensors (<NUM>) are arranged on a circumference.