Patent Publication Number: US-2022222802-A1

Title: System and method for measuring key features of a rotary milking parlor arrangement, computer program and non-volatile data carrier

Description:
TECHNICAL FIELD 
     The present invention relates generally to solutions for milking animals while being located on a rotating platform. Especially, the invention relates to a system for measuring a set of key features of a rotary milking parlor arrangement and a method implemented in such a system. The invention also relates to a corresponding computer program and a non-volatile data carrier storing such a computer program. 
     BACKGROUND 
     Today&#39;s automatic milking arrangements are highly complex installations. This is particularly true for rotary milking platforms, where a relatively large number of milking stations are served by at least one milking robot, or similar automatic equipment. Inter alia, this means that the milking robot attaches teatcups and other tools, e.g. cleaning cups, to the animals in a fully automatic manner. For successful operation, among other things, the milking robot must have adequate information about the physical characteristics of the rotary milking parlor arrangement. Typically, each arrangement is a customized installation, i.e. individually designed. Therefore, it is not possible to enter factory default data about the arrangement upfront for use by the control system for the milking robot. Instead, for each setup, the milking robot must be taught about (i.e. programmed with information describing) the specific configuration of the arrangement that the milking robot shall serve. This, in turn, is a very time-consuming process. Moreover, if the information is entered manually, there is an imminent risk that data errors are introduced. 
     SUMMARY 
     The object of the present invention is therefore to offer an improved solution for programming the control system for a milking robot with information describing the key features of a rotary milking parlor arrangement. 
     According to one aspect of the invention, the object is achieved by a system for measuring a set of key features of a rotary milking parlor arrangement. The arrangement, in turn, contains a rotating platform with a plurality of stalls, each of which is configured to house a respective animal during milking. The stalls are separated from one another by delimiting structures. The proposed system includes a camera and a control unit. The camera is configured to register three-dimensional image data of the rotating platform within a field of view, and the control unit is configured to process the registered image data. Specifically, the control unit is configured to receive the image data that has been registered while the rotating platform completes at least one full revolution around its rotation axis, process the image data to derive the set of key features, and store the set of key features in a data storage which is configured to make the set of key features available for use at a later point in time, e.g. via a cloud service. Inter alia, this enables the set of key features to be used in a so-called digital twin of the rotary milking parlor arrangement. 
     This system is advantageous because it provides reliable information about the physical characteristics of a rotary milking parlor arrangement in a fully automatic manner. 
     Preferably, the image data are registered while the rotating platform is empty of animals. Namely, this enables a higher data quality than if for example animals are located in one or more of the stalls. Moreover, if image data have been registered when the rotating platform is empty of animals, this data can then be compared with a data set registered when there are animals on the rotating platform, for instance via a subtractive operation, in order to conclude which visual objects that form part of the rotating platform, as such, and which visual objects that represent other entities, e.g. animals. This, in turn, may for example be advantageous when estimating a velocity of the rotating platform and/or controlling a robotic arm to perform actions in relation to animals located on the rotating platform. 
     According to one embodiment of this aspect of the invention, the control unit is further configured to process the image data to identify at least one recurring pattern therein, which recurring pattern represents a visual characteristic that is identical for all of said stalls on the rotating platform. Knowledge of such a recurring pattern facilitates navigation on the rotating platform and thus highly improves the chances of controlling a robotic arm successfully, for example after having found an entry window to reach an animal&#39;s teats. 
     Further preferably, the control unit is configured to make use of the information gathered in an automatic manner. For example, the control unit may be configured to retrieve the set of key features from the data storage; and based on the retrieved set of key features, run a search procedure investigating whether or not an entry window is available for controlling a robotic arm to perform an action relating to a milk-producing animal located in one of said stalls. Thereby, the efficiency of performing automatic milking as well as pre and post milking treatment of the animals&#39; teats can be increased significantly. 
     According to another embodiment of this aspect of the invention, the set of key features contains one or more of a respective width measure of each of the stalls, a respective height measure of the delimiting structures separating said stalls from one another, and a respective depth measure of each of the stalls. Thus, the set of key features provides highly relevant boundary conditions for controlling one or more robotic arms to perform actions relating to milk-producing animals on the rotating platform. 
     According to another embodiment of this aspect of the invention, the set of key features contains data describing the physical characteristics of at least one piece of fixed equipment that is arranged in at least one of said stalls. Hence, the at least one piece of fixed equipment may serve as a reference object for controlling a robotic arm. Preferably, at least one of the at least one piece of fixed equipment is arranged at a particular position in each stall on the rotating platform, and the particular position is the same for all stalls. Namely, thereby, key features describing the piece of fixed equipment in one stall can be reused to control the robotic arm in another stall. 
     According to other embodiments of this aspect of the invention, the control unit is configured to determine a current rotation angle of the rotating platform and/or a rotation speed of the rotating platform. The current rotation angle of the rotating platform is determined based on currently registered image data, and stored data retrieved from the data storage, e.g. by comparing key features derived from historic image data with current image data. The rotation speed of the rotating platform is determined based on image data registered at at least two points in time, and stored data retrieved from the data storage. Consequently, the stored data may be used also for controlling the rotating platform. 
     According to yet another embodiment of this aspect of the invention, the set of key features contains a position of a structure, which is arranged on a stationary part of the rotary milking parlor arrangement, which structure is configured to prevent the hind legs of an animal in one of said stalls from reaching outside of a safety zone for said one of said stalls. In other words, the set of key features may include data describing a location of a so-called kick rail. Since this structure is stationary, it will constitute a reliable reference for the other features in the set of key features. 
     According to another aspect of the invention, the object is achieved by a method of measuring a set of key features of a rotary milking parlor arrangement. The rotary milking parlor arrangement contains a rotating platform with a plurality of stalls, each of which is configured to house a respective animal during milking. The stalls are separated from one another by delimiting structures. The method includes the following steps. Via a camera, three-dimensional image data of the rotating platform are registered within a field of view. More precisely, the image data are registered while the rotating platform completes at least one full revolution around its rotation axis. The image data are processed to derive the set of key features. The set of key features are stored in a data storage, which is configured to make the set of key features available for use at a later point in time. The advantages of this method, as well as the preferred embodiments thereof, are apparent from the discussion above with reference to the system. 
     According to a further aspect of the invention, the object is achieved by a computer program loadable into a non-volatile data carrier communicatively connected to a processing unit. The computer program includes software for executing the above method when the program is run on the processing unit. 
     According to another aspect of the invention, the object is achieved by a non-volatile data carrier containing the above computer program. 
     Further advantages, beneficial features and applications of the present invention will be apparent from the following description and the dependent claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is now to be explained more closely by means of preferred embodiments, which are disclosed as examples, and with reference to the attached drawings. 
         FIG. 1  shows a system for measuring a set of key features of a rotary milking parlor arrangement according to one embodiment the invention; 
         FIG. 2  illustrates a camera&#39;s field of view of the rotary milking parlor arrangement in  FIG. 1 ; and 
         FIG. 3  illustrates, by means of a flow diagram, the general method according to the invention. 
     
    
    
     DETAILED DESCRIPTION 
     In  FIG. 1 , we see a rotating platform  130 , which forms part of a rotary milking parlor arrangement. In this example, the rotating platform  130  has 18 milking stalls S. Of course, however, any higher or lower number of stalls S is conceivable according to the invention. 
     According to the invention, a system for measuring a set of key features of the rotary milking parlor arrangement includes a camera  110  and a control unit  120 . The camera  110  is configured to register three-dimensional image data D img3D  of the rotating platform  130  within a field of view FV as illustrated in  FIG. 2 . 
     Preferably, the camera  110  is arranged in relation to the rotating platform  130  such that the field of view FV covers at least 1.5 of the milking stalls S. Namely, this provides a substantial overlap of the image data D img3D  registered in respect of each milking stall S, and thus enables high reliability in this data. 
     The control unit  120  is configured to process the registered image data D img3D . This may involve comparing, e.g. via a subtractive operation, first and second amounts of image data D img3D  with one another, where the first amount of image data D img3D  has been registered while the rotating platform  130  is empty of animals, and the second amount of image data D img3D  has been registered while at least one animal is present on the rotating platform  130 . Based on this comparison, the control unit  120  is preferably configured to determine at least one visual object in the first and second amounts of image data D img3D  that represents an object forming part of the rotating platform  130 . 
     Preferably, the camera  110  is a time-of-flight (ToF) camera, i.e. a range imaging camera system that resolves distance based on the known speed of light. According to the invention, however, the camera  110  may be any alternative imaging system capable of determining the respective distances to the objects being imaged, for example a 2D camera emitting structured light or a combined light detection and ranging (LIDAR) camera system. Moreover, the three-dimensional image data D img3D  may be dynamic. This means that the three-dimensional image data D img3D  can be represented by a video sequence and/or be built up from multiple still images. 
     The rotating platform  130  has a plurality of stalls S, where each stall S is configured to house a respective animal during milking. The stalls S are separated from one another by delimiting structures, for example in the form of rails DS 1  and DS 2  respectively. 
     Specifically, the control unit  120  is configured to receive the image data D img3D  having been registered while the rotating platform  130  completes at least one full revolution around its rotation axis, for instance in a forward rotation direction RF. The control unit  120  is further configured to process the image data D img3D  to derive the set of key features, and store the set of key features in a data storage  140 . The data storage  140 , in turn, is configured to make the set of key features available for use at a later point in time, e.g. by the control unit  120 . Thus, the data storage  140  may contain a digital storage medium, such as a hard drive, a Solid State Drive (SSD)/Flash memory and/or a Random Access Memory (RAM). 
     The set of key features may contain a first parameter reflecting a respective width measure W S  of each of the stalls S. Since the stalls S are shaped as truncated triangles, the width measure W S  may either express a width at an outer edge of the rotating platform  130 , a width at an inner edge thereof, or both. 
     Alternatively, or additionally, the set of key features may contain a second parameter reflecting a respective height measure H S  of the delimiting structures, e.g. DS 1  and DS 2 , that separate the stalls S from one another. 
     Alternatively, or additionally, the set of key features may contain a third parameter reflecting a respective depth measure D S  of each of the stalls S. For example, the depth measure D S  may be represented by a distance between the above-mentioned outer and inner edges of the rotating platform  130 . 
     During operation of the rotary milking parlor arrangement, the control unit  120  is preferably configured to retrieve the set of key features W S , H S  and/or D S  from the data storage  140 . Based on the retrieved set of key features W S , H S  and/or D S , the control unit  120  is further preferably configured to run a search procedure, which investigates whether or not an entry window is available for controlling a robotic arm to perform an action relating to a milk-producing animal that is located in one of the stalls S. Naturally, according to the invention, the set of key features W S , H S  and/or D S  may equally well be retrieved by any unit or device other than the control unit  120 , which unit or device is configured to control one or more robotic arms during operation of the rotary milking parlor arrangement. 
     According to one embodiment of the invention, the set of key features contains data describing the physical characteristics of at least one piece of fixed equipment that is arranged in at least one of the stalls S. For example, the at least one piece of fixed equipment may be represented by a cabinet or a rack for holding a milking cluster.  FIG. 2  symbolically illustrates such pieces of fixed equipment by EQ 1  and EQ 2  respectively. 
     Of course, the at least one piece of fixed equipment EQ 1  and/or EQ 2  may also constitute a portion of the delimiting structures DS 1  and/or DS 2 . 
     Ideally, at least one of the at least one piece of fixed equipment EQ 1  and/or EQ 2  is arranged at a particular position in each of the stalls S, which particular position is the same for all the stalls S on the rotating platform  130 . Consequently, a subset of key features describing this piece of fixed equipment in one of the stalls S can be reused in all the other stalls S on the rotating platform  130 . Such use of a repeating pattern highly improves the reliability of the registered information. 
     The control unit  120  may For example, be configured to associate at least one identified recurring pattern with a respective one of the at least one piece of fixed equipment EQ 1  and/or EQ 2  being arranged at a particular position in each of said stalls S, which particular position is the same for all of said stalls S on the rotating platform  130 . This, in turn, facilitates determining which visual objects in the image data D img3D  that form part of the rotating platform  130 , as such, and which visual objects that represent other entities, e.g. animals. Consequently, it is rendered comparatively straightforward for the control unit  120  to estimate a velocity of the rotating platform  130  and/or to control a robotic arm to perform actions in relation to animals located on the rotating platform  130 . 
     According to one embodiment of the invention, the control unit  120  is further configured to determine a current rotation angle of the rotating platform  130 . This rotation angle is determined based on currently registered image data D img3D , e.g. a fresh video image frame representing the rotating platform  130  within the field of view FV, and stored data that have been retrieved from the data storage  140 , for instance in the form of a set of key features derived from a historic video image frame representing the rotating platform  130 . 
     Further, according to another embodiment of the invention, the control unit  120  is configured to determine a rotation speed of the rotating platform  130 . The rotation speed is derived based on image data D img3D  registered at at least two points in time, and stored data retrieved from the data storage  140 , e.g. key features describing the width measure W S  of the stalls S, the height measure H S  of the delimiting structures DS 1  separating the stalls from one another and/or the depth D S  measure of the stalls S. 
     Thereby, the data in the data storage  140  may not only be used to control a robotic arm, however also to control the rotary platform  130  as such. 
     To enhance the data quality of the set of key features it is preferable to include a position P KR  of a structure  135  therein, which structure  135  is arranged on a stationary part of the rotary milking parlor arrangement. The structure  135  may thus be a so-called kick rail, i.e. a structure configured to prevent the hind legs of an animal in one of said stalls S from reaching outside of a safety zone for said one of said stalls S. The position P KR  may be a measure reflecting an elevation of the structure  135  relative to a part of the rotary milking parlor arrangement that has a known location, such as the rotating platform  130 , 
     It is generally advantageous if the control unit  120  and the camera  130  are configured to effect the above-described procedure in an automatic manner by executing a computer program  127 . Therefore, the control unit  120  may include a memory unit  125 , i.e. non-volatile data carrier, storing the computer program  127 , which, in turn, contains software for making processing circuitry in the form of at least one processor  125  in the central control unit  120  execute the above-described actions when the computer program  127  is run on the at least one processor  125 . 
     In order to sum up, and with reference to the flow diagram in  FIG. 3 , we will now describe the general method according to the invention of measuring a set of key features of a rotary milking parlor arrangement, which is presumed to contain a rotating platform with a plurality of stalls, each of which is configured to house a respective animal during milking, and where the stalls are separated from one another by delimiting structures. 
     In a first step  310 , three-dimensional image data of the rotating platform are registered via a camera. The three-dimensional image data are registered within a field of view of the camera. 
     Then, in a step  320 , the image data are stored; and in a subsequent step,  330 , it is checked if a rotary platform of said arrangement has completed a full revolution. If so, a step  340  follows; and otherwise, the procedure loops back to step  310 . 
     In step  340 , the image data are processed to derive the set of key features. 
     Thereafter, in a step  350 , the set of key features are stored in a data storage, which is configured to make the set of key features available for use at a later point in time. Subsequently, the procedure ends. 
     All of the process steps, as well as any sub-sequence of steps, described with reference to  FIG. 3  may be controlled by means of a programmed processor. Moreover, although the embodiments of the invention described above with reference to the drawings comprise processor and processes performed in at least one processor, the invention thus also extends to computer programs, particularly computer programs on or in a carrier, adapted for putting the invention into practice. The program may be in the form of source code, object code, a code intermediate source and object code such as in partially compiled form, or in any other form suitable for use in the implementation of the process according to the invention. The program may either be a part of an operating system, or be a separate application. The carrier may be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a Flash memory, a ROM (Read Only Memory), for example a DVD (Digital Video/Versatile Disk), a CD (Compact Disc) or a semiconductor ROM, an EPROM (Erasable Programmable Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), or a magnetic recording medium, for example a floppy disc or hard disc. Further, the carrier may be a transmissible carrier such as an electrical or optical signal which may be conveyed via electrical or optical cable or by radio or by other means. When the program is embodied in a signal, which may be conveyed, directly by a cable or other device or means, the carrier may be constituted by such cable or device or means. Alternatively, the carrier may be an integrated circuit in which the program is embedded, the integrated circuit being adapted for performing, or for use in the performance of, the relevant processes. 
     The term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components. However, the term does not preclude the presence or addition of one or more additional features, integers, steps or components or groups thereof. 
     The invention is not restricted to the described embodiments in the figures, but may be varied freely within the scope of the claims.