Milking system with cleanable teat detection device

Abstract

A milking robot (1) has a milking station (2), a control unit and a robot arm (3) for connecting milking cups (4). The robot arm has a teat detection device (5) having a transparent front element (18), and is moveable between a rest position outside the milking station and an operating area under the dairy animal. The milking robot is provided with a cleaning device for the front element, having a compressed-air device (20) on the robot arm and a fixedly arranged spraying device (6). The control unit selectively carries out the following: with the robot arm in the operating area, blowing compressed air onto the front element, and, with the robot arm in the rest position, spraying liquid onto the front element, and simultaneously or subsequently blowing compressed air onto said front element. By only using the liquid in the rest position outside the milking station, milk contamination and disturbance of the dairy animal is prevented. By contrast, cleaning with compressed air is available both at the milking station and in the rest position. Optimal, flexible and safe cleaning is thus provided.

Description

[0001] Milking system with cleanable teat detection device

[0002] The present invention relates to a milking robot having a milking station for receiving a dairy animal to be milked, having a control unit and having a robot arm for connecting a milking cup to a teat of the dairy animal, having, on the robot arm, a teat detection device having a transparent front element, wherein the robot arm is moveable between a rest position outside the milking station and an operating area under the dairy animal at the milking station for the purpose of the aforementioned connection, wherein said moving comprises pivoting from the side of the dairy animal into the operating area, wherein the milking robot is also provided with a cleaning device for cleaning at least said front element, wherein the cleaning device is controllable by the control unit.

[0003] Milking robots of this kind are generally known in the market. Milking robots almost always have an (optical) teat detection device. It is important to keep this teat detection device sufficiently clean, which is relatively difficult in a milking parlour environment. A cleaning device is often provided which can automatically clean the teat detection device, that is to say without any intervention from an operator.

[0004] Document US2013 / 247827A1 discloses such a milking robot, having a cleaning device for the front element with a sprayer and a blow-drying device, and also an optional extra sprayer outside the operating area in the outside world.

[0005] In practice, it is still difficult to also provide, in addition to good cleaning, an environment which is favourable both for the milk quality and animal welfare. The use of cleaning fluids should also be flexible, in order to be able to save on consumption as required. The known milking robots fall short in these respects.

[0006] It is therefore an object of the present invention to provide a milking robot of the specified type, which can clean flexibly and can also otherwise overcome, at least in part, the above-mentioned disadvantages.

[0007] To this end, the invention provides a milking robot according to Claim 1 , in particular a milking robot having a milking station for receiving a dairy animal to be milked, having a control unit and having a robot arm for connecting a milking cup to a teat of the dairy animal, having, on the robot arm, a teat detection device having a transparent front element, wherein the robot arm is moveable between a rest position outside the milking station and an operating area under the dairy animal at the milking station for the purpose of the aforementioned connection, wherein said moving comprises pivoting from the side of the dairy animal into the operating area, wherein the milking robot is also provided with a cleaning device for cleaning at least said front element, wherein the cleaning device is controllable by the control unit and comprises a compressed-air device having a compressed-air line which is provided on the robot arm and has a compressed-air discharge opening directed at said front element, and a spraying device having a liquid line with a liquid discharge opening in order to, with the robot arm in the rest position, spray liquid against said front element, wherein the control unit is configured to selectively carry out at least the following cleaning programmes: with the robot arm in the operating area, discharging compressed air from the compressed-air discharge opening onto said front element, and, with the robot arm in the rest position, discharging liquid from the liquid discharge opening onto said front element, followed by discharging compressed air from the compressed-air discharge opening onto said front element, wherein the spraying device of the cleaning device is provided exclusively on the fixed world frame.

[0008] The invention is based on the idea below. It is not advisable to spray liquid under the dairy animal. Not only is it unpleasant for the animal, but there is also the risk of liquid ending up in the milking cup, and thus potentially in the milk. Nevertheless, liquid is often the most effective cleaning fluid. It was therefore decided in the present invention to provide the liquid discharge opening outside the milking stall. In order to, however, offer the possibility of being able to clean the teat detection device when it is located under the dairy animal, thus in the operating area, the compressed-air line is provided on the robot arm, and in such a way that the compressed-air discharge opening is directed at the front element, and thus is always available in order to clean the front element with compressed air. The control unit is also configured to be able to selectively carry out various cleaning programmes, namely cleaning with compressed air when the teat detection device is located in the operating area, or at any other position, and cleaning with liquid and then with compressed air when the robot arm is located in the rest position, thus outside the operating area. Of course, there is the possibility of the control unit transferring the robot arm from the operating area to the rest position before the cleaning, if that is necessary in order to be able to connect milking cups at all, or to otherwise carry out an animal- related activity which requires the teat detection device to operate correctly.

[0009] Particular embodiments are described in the dependent claims, and in the part of the description that now follows.

[0010] In embodiments, the control unit is configured to carry out an additional cleaning programme, comprising, with the robot arm in the rest position, simultaneously discharging liquid from the liquid discharge opening and compressed air from the compressed-air discharge opening onto said front element. Supplying compressed air and liquid at the same time improves the (mechanical) effect of the cleaning, just as would be the case if liquid and compressed air were to be supplied by one and the same line.

[0011] In embodiments, the liquid line is or comprises a water line. This is of course the simplest form of a liquid line, which is in principle always available without restriction, but which already has an adequate cleaning effect. It is of course also possible to use a different liquid, in particular water with one or more cleaning agents, such as a soap or the like, added thereto. For example, a mixing device is provided on the water line, said mixing device comprising a container for cleaning agent and a mixing valve, mixing pump or the like.

[0012] For example, the teat detection device comprises a 2D camera or a 3D ToF camera. When using a 2D camera (video camera), a source of structured light is often used to determine the teat position. Examples of this are laser lines and also dot patterns, the deformation of the pattern being used to detect teats and their position. A 3D ToF camera, i.e. time-of-flight camera, emits pulsed or modulated light, the round trip time or, respectively, the phase shift of the reflected light with respect to the emitted light being used to determine the distance from the reflecting object. It is thus possible to construct a 3D image of the environment, after which image processing can be used to detect teats and their position. All such teat detection devices operate using light, and are relatively sensitive to soiling, such that good cleaning is highly desirable. However, alternatives are also possible, such as a stereo camera, or a 2D camera which is moveable on the robot arm, and therefore de facto functions as a stereo camera.

[0013] As an alternative or in addition, the teat detection device comprises a laser detector. This is a detector which projects laser lines with the aid of rotating mirrors, and measures the reflection with the aid of a series of light-sensitive detectors. The photodetectors which measure such reflection can be used as a basis for determining how great the angle of the reflection on, for example, a teat is. From this, it is possible to determine the position and distance of teats and the like. Such a laser detector is per se less sensitive to soiling, specifically by droplets or the like. Thus, cleaning with the aid of compressed air is often sufficient. Nevertheless, in some cases it may still be desirable or necessary to clean the laser detector, at least the front element thereof, with liquid.

[0014] In particular, the teat detection device comprises a laser detector having a housing, and also a 2D camera which has a main viewing direction and is in particular installed in said housing, and the compressed-air discharge opening is directed obliquely from above at a point above an intersection between said main viewing direction and the front element. In this case, a 2D (video) camera is thus also provided in addition to the laser detector. Said 2D camera may be provided as a separate camera, that is to say outside the housing of the laser detector, but it is preferably installed in the housing, such that the viewing direction is the same as that of the laser detector to the greatest possible extent. This is favourable when comparing and processing the measured data.

[0015] The 2D camera can provide independent data, such as a teat image for teat health or cleanliness. The 2D camera can also serve as an aid for the laser detector, for example by determining in the 2D image, via image processing, the direction in which there are teat candidates, or otherwise determining one or more regions of interest. In this case, the laser lines projected by and in front of the laser detector can, for their part, serve as an aid. The final position of the teats is determined by the more accurate laser detector which is more robust during measuring. This particular combination therefore provides the robustness of the laser detector and also the versatility and flexibility of an (optical) 2D camera. However, as mentioned, the 2D camera is often more sensitive to soiling, specifically to droplets, such as of water. By directing the compressed-air discharge opening, and thus the compressed-air flow, at a point above the point where the viewing direction of the 2D camera intersects the front element, with the compressed- air flow preferably being directed downwards, this compressed-air flow will largely sweep over the front element, and thereby entrain any dirt particles and / or droplets and thus remove them from the front element. The discharging of compressed air over the front element will furthermore also take place over that part of the front element which is in front of the laser detector, but will generally be less powerful. In this case, use is made of the fact that a laser detector is less sensitive to soiling.

[0016] In all of the embodiments above, liquid can also be sprayed over the front element in the rest position if required. This will preferably be effected from a position above the front element, such that the liquid will be able to flow away, together with dirt to be entrained, under the influence of gravity. Residual droplets can then be removed with the aid of the compressed air. Af fixed times, or for example if stubborn dirt is present, as detected by the teat detection device because there is for example a lack of sharp boundaries in the image, the control unit may choose to carry out a separate cleaning programme in which the liquid is thus sprayed and at the same time compressed air is discharged over the front element.

[0017] The invention will be explained in more detail below on the basis of some exemplary embodiments and the drawing. In the drawing:

[0018] - Figure 1 shows a schematic side view of a milking robot according to the invention, and

[0019] - Figure 2 shows a detail of the milking robot according to Figure 1 , in a schematic view of the robot arm 3 in the rest position.

[0020] Figure 1 shows a schematic side view of a milking robot 1 according to the invention for milking a dairy animal 50 with teats 51. The milking robot 1 comprises a milking station 2 with an operating area W, and a robot arm 3 which is moveable in the directions of the double-headed arrow A and is configured to connect milking cups 4 with the aid of a teat detection device 5. 6 denotes a spraying device, having a water line 7, and having an optional mixing device 8. A control unit is denoted by 9.

[0021] The milking robot 1 also comprises a feed trough 10, transverse members 11 and uprights 12. 13 denotes a connector of the spraying device 6 to the upright 12.

[0022] The milking robot 1 is of the type in which the robot arm 3 is firmly coupled to the milking station 2 for connection of the milking cups 4, and continuously remains in the operating area W during milking of the dairy animal 50. Although only one milking cup 4 is shown here for the sake of clarity, the shown robot arm 3 in principle bears all the milking cups 4 for the dairy animal 50, for example four for a cow. As an alternative, it is also possible to select a milking robot system in which the robot arm is moveable to two or more milking stations for the purpose of connecting the milking cups, or for example to select a milking robot in which milking cups are stored in a magazine from which they are picked up one by one by a robot arm. In the case of such milking robots, the robot arm usually does not remain in the operating area after connection, during milking. This makes no difference for the invention.

[0023] In the shown embodiment, the robot arm is at least moveable over the transverse member 11 in the direction of the double-headed arrow A. In addition, at least part of the robot arm 3 is moveable in a direction perpendicular to arrow A. In this case, the robot arm 3, at least the portion which bears the milking cups 4, can be moved between an operating area W and a rest position. Here, the operating area W is defined as the area where the robot arm 3 can be operative, in this case under the dairy animal 50 between the front and rear legs. Here, the rest position is defined as the position which the robot arm 3 occupies between milking sessions, in this case functionally at or towards the spraying device 6, in such a way that the latter can clean the teat detection device 5 on the robot arm.

[0024] The shown milking robot 1 also comprises a milking stall with transverse members 11 supported by uprights 12. Furthermore, at least one entry gate and one exit gate will also be provided, which are provided on the other side of the dairy animal 50 in the drawing, and therefore are not visible here. Moreover, the gates may also be provided at the front and rear of the milking station 2 / the milking stall. The milking robot 1 is also provided with standard components such as a feed trough 10, and also components that are not shown such as a vacuum system, a milking glass, etc. These are also not relevant to the invention.

[0025] For connection of the milking cups 4, the position of the teats 51 must be determined. To this end, the milking robot 1 comprises a teat detection device 5, for example a laser scanner or 3D camera. In use in the specified non-clean milking parlour environment, this teat detection device will possibly become soiled, with dust, manure splatters, etc. This soiling can have a negative influence on the proper operation of the teat detection device, and should therefore be regularly removed. For this soiling removal, both a spraying device 6 and a compressed-air device (not shown here) are provided according to the invention.

[0026] The spraying device 6 is connected to the milking stall, and thus to the outside world, by means of a rod 13. Of course, other approaches are also possible, such as a foot or the like which is connected directly to the ground, a wall, etc. The spraying device 6 is located outside the operating area W, specifically to prevent sprayed liquid from ending up in the milk or on the dairy animal 50.

[0027] The spraying device 6 sprays liquid, in this case water, out of a (water) line 7. The latter may branch off directly from the water network, or from a separate container such as a boiler for heated water. In this case, an optional mixing device 8 is provided, which is configured to add at least one additive to the water, such as in particular a soap or another detergent. To this end, the mixing device 8 may, for example, comprise at least one additive container having a connection, which is for example closable by means of a flap, to the line 7, or a pump or another metering device. Such mixing devices are known per se in the prior art.

[0028] In this case, the control unit 9 is operatively connected to the spraying device 6 and to the compressed-air device (not shown) on the robot arm 3. In addition, said control unit may be operatively connected to other components of the milking robot 1 which may or may not be shown, such as the robot arm 3, namely the actuators thereof, the vacuum system for performing milking, the feed trough 10 with a feed dispensing system, etc. One or more separate control units may also be provided for this. The control unit 9 may then optionally be connected to those separate control units. However, it is also possible for the control unit 9 to autonomously ensure cleaning of the teat detection device 5.

[0029] The cleaning of the teat detection device 5 with the aid of the spraying device 6 and the compressed-air device (not shown) will be described in more detail on the basis of Figure 2.

[0030] Figure 2 shows a detail of the milking robot according to Figure 1 , in a schematic view of the robot arm 3 in the rest position.

[0031] The teat detection device 5 comprises a housing 15, containing a laser detector 16 and a video camera 17, and also a front element 18. 20 denotes a compressed-air device, comprising a compressed-air line 21 and a compressed-air discharge opening 22, for a compressed-air flow 23 having a first main discharge direction 24 directed at a first point 28.

[0032] The spraying device 6 has a liquid discharge opening, i.e. spray opening 25, for a spray cloud 26 having a second main discharge direction 27 directed at a second point 29, and receives liquid from a liquid line 30.

[0033] The video camera 17 has a third main viewing direction 31 , which intersects the front element 18 at the third point 32.

[0034] The shown teat detection device 5 is only an example, and alternatives are discussed below. When the teat detection device 5 is in use, it can become soiled with dust, manure droplets, etc. These can impair the operation if they end up on the front element 18. This element 18 is produced from a transparent material, often glass or a hard plastic such as polycarbonate. The element 18 can be cleaned manually, but this is obviously very labour-intensive, although it cannot always be avoided in the event of stubborn soiling. For simple dirt, it may already be sufficient to blow it away. To this end, the compressed-air device 20 is provided. This feeds compressed air from a compressed-air source (not shown) via the compressed-air line 21 , and discharges it via the compressed-air discharge opening 22 in a compressed-air flow 23. Of course, it is not a very sharply defined flow, but the main discharge direction, corresponding to the "direction" of the compressed-air discharge opening 22, is indicated by the dashed line 24.

[0035] The compressed air is relatively effective for blowing away dust and the like. It is also not a problem to use compressed air when the teat detection device 5 is located in the operating area W under the dairy animal. If the robot arm is located in the operating area W, the control unit is therefore configured to carry out a cleaning programme comprising discharging compressed air from the compressed-air discharge opening 22 onto the front element 18.

[0036] For stubborn dirt, it is possible to spray cleaning liquid onto the front element

[0037] 18. This may be the case when the robot arm 3 is located in the rest position, that is to say near the spraying device 6, as shown in Figure 2. The rest position is not under the dairy animal, in order to prevent liquid from being able to end up in the milk, or from being able to disturb the dairy animal. In the rest position, the control unit can thus also carry out a different cleaning programme comprising discharging liquid from the liquid discharge opening 25 onto the front element 18, followed by discharging compressed air from the compressed-air discharge opening 22 onto the front element 18. Here, the intention is for the water to loosen and entrain the stubborn dirt, after which residual droplets and any loosened but remaining dirt is blown away.

[0038] In the case of particularly stubborn dirt, it is possible for the control unit to also carry out another cleaning programme comprising simultaneously discharging liquid from the liquid discharge opening 25 and compressed air from the compressed-air discharge opening 22 onto the front element 18. Here, the compressed air ensures that the mechanical effect of the liquid is strengthened, since the force on the dirt will fluctuate rapidly. Of course, this can, as required, involve the compressed air being lastly or additionally blown onto the front element 18 in order to remove loosened dirt and / or droplets from the front element 18.

[0039] In this shown example, the teat detection device 5 comprises, in the housing 15, a laser scanner 16 and a video camera 17. Here, the laser scanner 16 comprises, as known in the prior art, a laser source and a series of light detectors which detect the reflection of the emitted laser beam, and from said reflection determine a distance from the reflecting body. In this case, the video camera 17 may be provided to carry out additional functions, such as determining teat health, for example redness at a wound, but also cleanliness of the teat, etc. It is also possible for the video camera 17 to have a supporting role in the teat detection, such as indicating that the laser scanner is not projecting the laser beam onto the correct teat, but for example onto an incorrect teat or onto a rear leg. Finally, it is also possible for the video camera 17, in addition to the series of light detectors for the laser scanner 16, to operate as a detector for the reflection of the laser beam in order to thereby determine the position of the teats and the like, as is also known per se in the prior art.

[0040] In practice, the laser scanner 16, thus the laser source in combination with the series of light detectors, is often still less sensitive to dirt on the front element 18, and specifically droplets, than the video camera 17. In the shown example in Figure 2, the liquid flow 26 is directed perpendicularly with respect to the front element 18, and at a point 29 slightly above the main viewing direction 31 of the video camera 17. Of course, the liquid flow 26 will spread out on the front element 18, and thus can, in principle, clean the entire front element. Here, a reasonable compromise is achieved between cleaning a first part of the front element 18 in front of the video camera 17 and another part in front of the laser detector 16. It is of course also possible for the liquid flow 26, with regard to the second main discharge direction 27 thereof, to be directed perpendicularly with respect to the video camera, such that point 29 lies in front of the video camera 17. This ensures optimal cleaning of said first part of the front element.

[0041] Compressed air from the compressed-air device 20 is used to dry the front element 18. The main discharge direction 24 of the compressed-air flow 23 is directed obliquely from above at point 28 on the front element 18. This point 28 lies above point 32 forming the intersection between the main viewing direction 31 of the video camera 17 and the front element 18. In practice, it is still favourable to supply the air obliquely and above the video camera, such that the air can entrain the droplets downwards, assisted by gravity. In addition, it is the case that the air flow will disperse over the front element 18, such that ultimately, in principle, all the droplets will be blown away. Nevertheless, the shown positioning of the air flow is advantageous for the video camera, which is more sensitive to soiling.

Claims

CLAIMS1. Milking robot having a milking station for receiving a dairy animal to be milked, having a control unit and having a robot arm for connecting a milking cup to a teat of the dairy animal, having, on the robot arm, a teat detection device having a transparent front element, wherein the robot arm is moveable between a rest position outside the milking station and an operating area under the dairy animal at the milking station for the purpose of the aforementioned connection, wherein said moving comprises pivoting from the side of the dairy animal into the operating area, wherein the milking robot is also provided with a cleaning device for cleaning at least said front element, wherein the cleaning device is controllable by the control unit and comprises- a compressed-air device having a compressed-air line which is provided on the robot arm and has a compressed-air discharge opening directed at said front element, and- a spraying device having a liquid line with a liquid discharge opening in order to, with the robot arm in the rest position, spray liquid against said front element, wherein the control unit is configured to selectively carry out at least the following cleaning programmes:- with the robot arm in the operating area, discharging compressed air from the compressed-air discharge opening onto said front element, and- with the robot arm in the rest position, discharging liquid from the liquid discharge opening onto said front element, followed by discharging compressed air from the compressed-air discharge opening onto said front element, wherein the spraying device of the cleaning device is provided exclusively on the fixed world frame.

2. Milking robot according to Claim 1 , wherein the control unit is configured to carry out an additional cleaning programme, comprising, with the robot arm in the rest position, simultaneously discharging liquid from the liquid discharge opening and compressed air from the compressed-air discharge opening onto said front element.

3. Milking robot according to one of the preceding claims, wherein the liquid line is or comprises a water line.

4. Milking robot according to one of the preceding claims, wherein the teat detection device comprises a 2D camera or a 3D ToF camera.

5. Milking robot according to one of the preceding claims, wherein the teatdetection device comprises a laser detector.

6. Milking robot according to one of Claims 1-4, wherein the teat detection device comprises a laser detector having a housing, and also a 2D camera which has a main viewing direction and is in particular installed in said housing, and wherein the compressed-air discharge opening is directed obliquely from above at a point above an intersection between said main viewing direction and the front element.

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