Measuring device and measuring system for determining hoof moisture

Abstract

Measuring device (1) for determining hoof moisture, characterized in that the measuring device (1) has an impedance spectroscopic measuring probe (3) which has a probe surface (30) that can be arranged directly on a hoof (2) with at least one electrode arrangement (4) connected to an alternating current supply, each having electrodes (41, 42).

Description

[0001] The present invention relates to a measuring device for determining hoof moisture. The invention further relates to a measuring system comprising the measuring device for determining hoof moisture.

[0002] Particularly in cattle, a correlation has been found between hoof moisture and specific diseases. In healthy cattle, the water content of the horn, from which the hooves are formed, ranges between 15 and 30%. Excessive water content leads to swelling and softening of the horn. Conversely, very low horn water content results in horn brittleness with shrinkage and cracking. If deviations in horn quality are detected, measures regarding breeding, husbandry, and management can be implemented to improve hoof health.

[0003] Currently, hoof horn moisture analysis involves taking hoof horn samples in the form of shavings from cattle hooves, which are then subjected to a complex gravimetric laboratory analysis. Due to the invasive nature of the sampling procedure, stress and injury to the animal cannot be ruled out. Furthermore, the results are only available after several days, and the procedure is expensive because it requires specialized laboratory equipment and trained personnel.

[0004] It is therefore the object of the present invention to provide a measuring device and a corresponding measuring system with which hoof moisture can be determined directly on the animal on site with the highest possible accuracy and speed, without harming or stressing the animal.

[0005] This task is solved, firstly, by a measuring device for determining hoof moisture, which has an impedance spectroscopic measuring probe that has a probe surface that can be arranged directly on a hoof and has at least one electrode arrangement connected to an alternating current supply, each having electrodes.

[0006] The measuring device according to the invention uses impedance spectroscopy to determine hoof moisture. For this purpose, the probe surface of the measuring probe is placed on a hoof whose moisture is to be measured. An electric field is then generated by the at least one electrode arrangement, which penetrates the horn material of the hoof. The bulk moisture content of the hoof can then be determined by measuring the impedance as a function of the measurement frequency. The measured impedance can be evaluated, for example, by comparison with calibration curves, in order to determine the actual moisture content of the hoof. The animal whose hoof is being measured is not affected by this process.

[0007] The measuring device according to the invention can be designed to be so small and light that it can be used as a handheld measuring device.

[0008] For determining hoof moisture, the measuring device according to the invention only requires impedance measurements to be performed at a few frequencies, thus keeping the measurement time very short. It is only a few seconds, preferably less than 4 seconds. Nevertheless, the measured values ​​are very precise.

[0009] In an advantageous embodiment of the measuring device according to the invention, the electrodes of the respective electrode arrangement are nested within one another. This allows the electrode arrangement, and thus also the probe surface, to be kept small. Due to the uneven claw surface, this has the advantage that a relatively flat portion of the claw can be accurately measured with the correspondingly small probe surface.

[0010] Additional advantages arise when the electrodes are each designed as a plurality of circular rings connected on one side and interrupted on the other. This results in a circular electrode arrangement that can generate a uniform electric field.

[0011] The electrodes of at least one electrode arrangement are preferably made of metal. If silver or platinum is used for the electrodes, they are particularly durable.

[0012] It has also proven advantageous if at least one electrode arrangement is mounted on an electrically insulating substrate on which the electrodes are mounted. The electrically insulating substrate is preferably made of a ceramic, preferably of Al₂O₃.

[0013] The probe surface can adapt well to the uneven claw surface being measured if at least one electrode array is mounted on a mechanically flexible carrier. During measurement, a certain amount of pressure can then be applied to the carrier, pressing the probe surface with the at least one electrode array onto the claw, resulting in optimized measurement results.

[0014] The mechanically flexible support can be made of high-strength rubber and / or at least a flexible plastic. These materials are not only flexible but also easy to clean.

[0015] It is particularly advantageous to have several electrode arrangements distributed side by side on the mechanically flexible carrier. The multiple electrode arrangements allow for a relatively large claw surface to be captured during measurement. Because the carrier is made of a flexible material, the large claw surface can be captured effectively even if it is uneven, as the electrode arrangements can then rest on the claw at an angle relative to each other.

[0016] In another, equally advantageous embodiment of the present invention, distance sensors can be arranged around the at least one electrode arrangement. These distance sensors can detect the air gap existing between the respective electrode arrangement and the claw surface and include it in the moisture calculation.

[0017] To achieve a significantly shorter measurement time compared to conventional impedance measurements, it has proven particularly advantageous if the measuring device is one that performs impedance measurements at only a few fixed frequencies. This allows the measurement time of the measuring device according to the invention to be limited to just a few seconds, during which the positioning of the measuring probe relative to the claw on which the measurement is taken remains practically constant.

[0018] To achieve an even shorter and therefore particularly practical measurement time, in a preferred embodiment of the present invention the measuring device is a device operating on the principle of multisine electrochemical impedance spectroscopy. In this principle, the excitation sine signals of the measurement frequencies are superimposed and the signal response is separated back into the signals of the individual frequencies by Fast Fourier Transform (FFT).

[0019] The problem is further solved by a measuring system for determining hoof moisture, which comprises a measuring device designed according to the invention with a data transmission device coupled to a data receiving and evaluation device. With the measuring system according to the invention, data measured at the measuring device can be transmitted via the data transmission device to the data receiving and evaluation device and evaluated there. This has the advantage that no data evaluation device or data storage device needs to be provided on the measuring device itself, which allows the measuring device to be designed to be lightweight and easy to handle. The data receiving and evaluation device can be arranged centrally. Furthermore, a single data receiving and evaluation device can be used to process data from several measuring devices designed according to the invention.

[0020] In an advantageous embodiment of the measuring system according to the invention, the measuring system includes an animal identification device that is coupled to the data reception and evaluation device. This allows the data measured by the measuring device to be directly assigned to an animal.

[0021] Preferred embodiments of the present invention are explained in more detail below with reference to figures, wherein Fig. 1 schematically shows an embodiment of a measuring system according to the invention with an embodiment of a measuring device according to the invention in a side view before a measurement on a claw of an animal; Fig. 2 schematically the measuring system Fig. 1 shows during a measurement of the claw in a side view; Fig. 3 schematically and exemplarily shows impedance values ​​determined on a claw using an embodiment of the measuring system according to the invention; Fig. Figure 4 schematically and exemplarily shows the relationship between impedance values ​​determined on a claw with an embodiment of the measuring system according to the invention and the horn moisture of the claw; Fig. 5 schematically shows an electrode arrangement used in an embodiment of the measuring device according to the invention in a top view; Fig. Figure 6 schematically shows an electrode arrangement with distance sensors used in a further embodiment of the measuring device according to the invention in a top view; and Fig. Figure 7 schematically shows a probe surface of an embodiment of the measuring device according to the invention with several electrode arrangements in a top view.

[0022] Fig. Figure 1 schematically shows an embodiment of a measuring system 10 according to the invention with a measuring device 1 according to the invention arranged opposite a claw 2 of an animal 16 shown separately in the figure above, before a measurement in a side view. Fig. 2 shows the measuring system Fig. 1 during a measurement at the claw 2.

[0023] Claw 2, for example, is a claw from a living, standing cow. In the case shown, claw 2 has an uneven, convex claw surface 20. Depending on the location of the measurement on claw 2, claw 2 may also have a differently shaped, for example, flat, claw surface 20.

[0024] The measuring device 1 has a housing 6 with a handle 7.

[0025] The measuring device 1 has a measuring probe 3 that is aligned with the claw 2 and placed on the claw surface 20 during a measurement. The measuring probe 3 is held in the housing 6, with one probe surface 30 of the measuring probe 3 being openly accessible. During measurement, the probe surface 30 is positioned opposite the claw surface 20. In the illustrated embodiment, the probe surface 30 is flat. Due to the curvature of the claw surface 20, the probe surface 30 can initially only rest directly on a portion of the claw surface 20.

[0026] In the illustrated embodiment, however, the measuring probe 3 has a carrier 5 made of a flexible material. In the illustrated embodiment, the flexible material is rubber, but it can also be a flexible plastic. Therefore, if the measuring probe 3 is pressed against the claw 2, for example by means of the handle 7, the probe surface 30 can conform better to the claw 2 and a larger part of the claw surface 20 can be measured by the measuring probe 3.

[0027] The measuring probe 3 has an electrode arrangement 4 on its probe surface 30, which at least partially rests on the claw surface 20 during measurement.

[0028] In the embodiment shown, the electrode arrangement 4 has two electrodes 41, 42, each of which is formed, for example, in the form of several concentrically arranged and electrically connected rings.

[0029] In the illustrated embodiment, the electrode arrangement 4 is mounted on an electrically insulating substrate 13. In this embodiment, the substrate 13 is made of a material with a low ε, in particular an ε < 4, such as Al₂O₃. This allows for optimal measurement of the moisture content of the claw 2.

[0030] Electrodes 41 and 42 are each electrically contacted. For this purpose, the measuring device 1 has electronics 8 which are connected to a power supply 9. In the illustrated embodiment, the power supply 9 is provided by a battery. Alternatively, the measuring device 1 can also be connected to a mains power supply via a cable, which then serves as the power supply.

[0031] In the illustrated embodiment, distance sensors 14 are arranged around the electrode arrangement 4. The distance sensors 14 each detect a distance to the claw surface 20 and transmit the measured distance data to the electronics 8.

[0032] When an electrical voltage is applied to the electrodes 41, 42, an electric field penetrates the horn material of the claw 2 when the electrode arrangement 4 rests on the claw 2, so that an electric current can flow from a first electrode 41 through the material of the claw 2 to the second electrode 42 and an impedance of the horn material can be determined.

[0033] In measuring device 1, the impedance of the horn material is determined using an alternating current at several measurement frequencies f. The method used for this is an impedimetric or impedance spectroscopic measurement method.

[0034] Here, as in Fig. 2 schematically shown, the measuring probe 3 placed on the claw 2 and then the dependence Z = f (f) recorded, as schematically shown in Fig. Figure 3 shows that the impedance measured at each claw 2 depends on the measurement frequency f and is also dependent on humidity. This allows the measuring device 1 to determine the moisture content of the horn material of claw 2 within a few seconds. The measurement on animal 16 takes no more than 4 seconds in total. This takes into account the animal's high activity level.

[0035] Multisine electrochemical impedance spectroscopy is preferably used in the measurement system 10. In this method, the excitation sine signals of the measurement frequencies are superimposed, and the signal response is separated back into the signals or individual frequencies using Fast Fourier Transform (FFT). The increased effort required for signal generation and evaluation is justified by the extremely short measurement time.

[0036] As shown schematically in Fig. As shown in 3, the impedance Z determined in each case is a complex value consisting of real part Z' and imaginary part Z'', which is in Fig. Figure 2 shows the curves at several different, fixed measurement frequencies f. The corresponding measurement curves are also known as Nyquist curves. The humidity measurement is therefore a multidimensional result.

[0037] When evaluating the measured impedance values ​​Z, they are assessed as a function of the frequency f. Depending on the deviation from a calibration curve, the actual humidity level can be determined.

[0038] For further evaluation of the measured impedance values ​​Z, their compression to a characteristic parameter is required. For example, from the Fig. The radius of the typical semicircular curve segment, i.e., the segment shown in Figure 3, represents the course of the impedance curves. Fig. The 3 left curve section can be used to determine an RC element.

[0039] Nyquist curves have various parameters, such as the position of the circle's center point, its diameter, or the position of the point at the transition from the circular to the linear section. These parameters can be used for comparison with stored calibration curves.

[0040] Previous studies have shown that the optimal measurement frequencies are found in a frequency range of 1 Hz to approximately 100 kHz. To ensure that the signals are harmless and imperceptible to animal 16, the signal amplitude should not exceed 1 V.

[0041] Fig. Figure 4 shows schematically and by way of example the relationship between impedance values ​​Z determined with an embodiment of the measuring system 10 on a claw 2 and the horn moisture H of the claw 2.

[0042] The electronics 8 are in the Fig. In the embodiment shown in Figure 1, the measuring system 10 is connected to a data transmission device 11. The data transmission device 11 can, for example, be a radio module or a Bluetooth module. In the embodiment shown, the data transmission device 11 is also supplied with energy via the power supply 9.

[0043] The electronics 8 receive the measured impedance data from the electrode arrangement 4. The electronics 8 transmit this impedance data, as well as the distance data, for example via electrical conductors provided in the measuring device 1, to the data transmission device 11, which then transmits the impedance and distance data to a data reception and evaluation device 12 located outside the measuring device 1. The data reception and evaluation device 12 can be, for example, a computer, a tablet, a smartphone, or a cloud connected to a computing unit. The data reception and evaluation device 12 can be integrated into a milking system or be a separate unit. The data transmission from the measuring device 1 to the data reception and evaluation device 12 and the data reception by the data reception and evaluation device 12 are automated.The data reception and evaluation unit 12 allows the moisture data of the hooves 2 determined on one or more animals 16 to be visualized and tracked and monitored over a longer period of time on a specific animal 16 or a defined group of animals 16.

[0044] In the illustrated embodiment, the measuring device 1 further comprises a display unit 17, on which current measurement data and trends of the measuring device 1 can be displayed to a user of the measuring device 1. The display unit 17 is electrically connected to the electronics and the power supply 9.

[0045] Measuring device 1 can be used directly on site. Measuring device 1 is a point-of-care rapid measuring device for determining the moisture or water content in hooves 2.

[0046] The measuring system 10 also includes an animal identification device 15 attached to each animal 16, which is coupled to the data receiving and evaluation device 12, for example via radio. The animal identification device 15 transmits a digital identifier of the animal 16 to the data receiving and evaluation device 12. In the data receiving and evaluation device 12, the measurement data received by the measuring device 1 are directly assigned to the animal 16 on which the measurements were taken.

[0047] Fig. Figure 5 schematically shows a top view of an electrode arrangement 4 used in one embodiment of the measuring device 1 according to the invention. The electrode arrangement 4 has two nested electrodes 41, 42, each consisting of several interconnected circular rings, which are mounted on an electrically insulating base 13.

[0048] Fig. Figure 6 schematically shows an electrode arrangement 4 of an embodiment of a measuring device 1 designed according to the invention, with distance sensors 14 arranged around the electrode arrangement 4, in a top view. The electrode arrangement 4 has, as in the embodiment of Fig. 4, two nested electrodes 41, 42, each consisting of several interconnected circular rings, which are applied to an electrically insulating substrate 13.

[0049] Fig. Figure 7 schematically shows a probe surface 30 of an embodiment of the measuring device 1 according to the invention with several electrode arrangements 4, each as shown in the Fig. 4 and Fig. The electrodes 41 and 42 of the electrode assemblies 4 are each arranged on an electrically insulating base 13. In the illustrated embodiment, the electrode assemblies 4 are distributed on a flexible support 5. This allows the electrode assemblies 4 to tilt relative to each other.

[0050] In the Fig. 5, Fig. 6 to Fig. 7 the electrode arrangements 4 consist of silver or platinum, the substrate 13 is in each case made of Al2O3, whereby in other embodiments of the present invention other materials may also be used.

[0051] In the Fig. 5 and Fig. In section 6, the electrode arrangement 4 has a diameter in the range of 10 to 25 mm. Fig. 7 all three electrode arrangements 4 are located together on an area with a diameter of 10 to 25 mm.

Claims

[1] Measuring device (1) for determining hoof moisture, characterized by , that the measuring instrument (1) has an impedance spectroscopic measuring probe (3) which has a probe surface (30) that can be arranged directly on a claw (2) with at least one electrode arrangement (4) connected to an alternating current supply, each having electrodes (41, 42). [2] Measuring device according to claim 1, characterized by , that the electrodes (41, 42) of the respective electrode arrangement (4) are nested inside each other. [3] Measuring device according to claim 2, characterized by , that the electrodes (41, 42) are each formed in the form of a plurality of circular rings connected on one side and interrupted on the other side. [4] Measuring device according to one of the preceding claims, characterized by , that the electrodes (41, 42) of the at least one electrode arrangement (4) are made of silver or platinum. [5] Measuring device according to one of the preceding claims, characterized by , that at least one electrode arrangement (4) is formed on a substrate (13) made of Al2O3, on which the electrodes (41, 42) are applied. [6] Measuring device according to one of the preceding claims, characterized by , that at least one electrode arrangement (4) is arranged on a mechanically flexible support (5). [7] Measuring device according to claim 6, characterized by , that the mechanically flexible support (5) is made of rubber and / or at least a flexible plastic. [8] Measuring device according to claim 6 or 7, characterized by , that several electrode arrangements (4) are distributed side by side on the mechanically flexible carrier (5). [9] Measuring device according to any one of the preceding claims, characterized by , that at least one electrode arrangement (4) distance sensors (14) are arranged around. [10] Measuring device according to any one of the preceding claims, characterized by , that the measuring instrument (1) is a measuring instrument that performs impedance measurements only at a few fixed frequencies. [11] Measuring device according to any one of the preceding claims, characterized by , that the measuring instrument (1) is a measuring instrument operating according to the principle of multisine electrochemical impedance spectroscopy. [12] Measuring system (10) for determining hoof moisture, characterized by , that the measuring system (10) comprises a measuring device (1) according to one of the preceding claims with a data transmission device (11) coupled to a data reception and evaluation device (12). [13] Measuring system according to claim 12, characterized by , that the measuring system (10) has an animal identification device (15) which is coupled to the data receiving and evaluation device (12).

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