CN212212261U - Device for determining the spatial position of the teat of an animal and milking device - Google Patents

Abstract

An apparatus for determining the spatial position of a teat of an animal and a milking apparatus is provided with a first emitter element for emitting a first ray to a first sub-area of the space and a second emitter element, different from the first emitter element, for emitting a second ray to a second sub-area of the space. The first and second sub-areas together constitute said space. The first receiver element is arranged to receive a reflection of the first ray 27. A second receiver element, different from the first receiver element, is for receiving the reflection of the second ray. A single mirror rotatable about an axis of rotation directs radiation emanating from each transmitter element into an associated plane of an associated sub-region of the space and/or directs radiation reflected from the associated sub-region to an associated receiver element. A means directs radiation emanating from each emitter element into at least two spaced apart relative position-determining surfaces of a relative sub-region of the space.

Description

Device for determining the spatial position of the teat of an animal and milking device

Technical Field

The present invention relates to an apparatus for determining the spatial position of the teats of an animal and to a milking apparatus.

Background

Such a device is known from international patent application WO 99/09430. Although such a device functions satisfactorily and is adapted for determining the position of the teat very accurately in some situations, for example in the case of a tilting teat, it seems to be still desirable to improve the determination of the position.

SUMMERY OF THE UTILITY MODEL

It is an object of the present invention to provide an apparatus for determining the spatial position of a teat of an animal, which apparatus enables an improved determination of the position.

To this end, according to a first aspect of the invention, an apparatus for determining the spatial position of a teat of an animal is provided. Since at least two spaced apart position determining surfaces are obtained, the position can be determined more accurately since the determination of the position in terms of nipple height is also obtained so that the inclination of the nipple can be determined.

In an embodiment of the device according to the invention, the mirror is constituted by a polygon having at least two reflecting surfaces, at least one of which is angled differently with respect to the axis of rotation than one of the remaining reflecting surfaces. Due to the use of the polygon, the rotational synchronization of the reflecting surface is obtained in a simple constructional manner. Thereby, further processing of the data is also simplified.

The apparatus is preferably provided with means for directing the radiation or radiation beam emanating from each emitter element into three spaced apart relative position-determining surfaces of the associated sub-region of space. In practice, it seems that in almost all cases, the use of three position determination surfaces is sufficient to determine the position of the nipple.

In an embodiment of the device according to the invention, the mirror is constituted by a pentagon having five reflecting surfaces, one of which is parallel to the axis of rotation, two of which are at equal positive angles with respect to the axis of rotation and the remaining two are at equal negative angles with respect to the axis of rotation. Thus, three position determining surfaces are obtained, the two outer surfaces being scanned twice during one revolution of the pentagon. Thus, a very accurate determination of the position of the nipple, in particular the inclination determination, can be obtained. It is particularly advantageous when said positive and negative angles are between approximately 3 ° and approximately 13 °.

In an alternative embodiment of the device according to the invention, two of the reflecting surfaces are parallel to the axis of rotation, one of the reflecting surfaces is at a first angle with respect to the axis of rotation and the remaining two reflecting surfaces are at a second angle with respect to the axis of rotation. The first angle is preferably between approximately 1 ° and approximately 7 °, and the second angle is preferably between approximately 1 ° and approximately 20 °. A particularly accurate determination of the position of the nipple is obtained when the second angle is at least approximately twice as large as the first angle.

The invention further relates to a device for determining the position of the teat of an animal relative to the device, said device being provided with: a transmitter element for transmitting a radiation or a radiation beam; at least one receiver element arranged for receiving the radiation or radiation beam reflected by the nipple; and at least one reflective surface which is rotatable about an axis of rotation for continuously guiding a ray or ray bundle emanating from the emitter element to the teat and/or for guiding a ray or ray bundle emanating from the teat to the receiver element, characterized in that means are provided for changing the orientation of the reflective surface relative to the teat during rotation of the reflective surface. Since means are provided for changing the orientation of the reflecting surface relative to the nipple during rotation of the reflecting surface, several surfaces are obtained during rotation into which rays, respectively beams of rays, are emitted. Thus, in addition to determining the position, the position in terms of the height of the nipple can also be determined, so that the inclination of the nipple can be determined. The change and the synchronization of the data thus obtained can be realized by a computer, so that the processing of the data can be accurately performed. It is clear that on the one hand the change of orientation can be gradual, such as continuous, but on the other hand a discrete change of orientation is also possible.

The means is preferably adapted to change the orientation of the reflective surface relative to the axis of rotation. Additionally or alternatively, the means is adapted to change the orientation of the axis of rotation. Such a change can be obtained, for example, by an eccentric suspension or a curved disk or the like.

The invention further relates to a device for determining the position of the teat of an animal relative to the device, said device being provided with: a transmitter element for transmitting a radiation or a radiation beam; at least one receiver element arranged for receiving the radiation or radiation beam reflected by the nipple; and a mirror which is rotatable about an axis of rotation for successively directing the radiation or radiation beam emanating from the emitter element to the nipple and/or for directing the radiation or radiation beam emanating from the nipple to the receiver element, characterized in that the mirror is constituted by a polygon having at least two reflecting surfaces, at least one of which is at a different angle relative to the axis of rotation than one of the remaining reflecting surfaces. Due to the presence of at least two reflecting surfaces, wherein at least one of the reflecting surfaces is angled differently with respect to the axis of rotation compared to one of the remaining reflecting surfaces, at least two spaced apart surfaces are obtained into which the radiation, respectively the radiation beam, is emitted. Thus, in addition to determining the position, the position in terms of the height of the nipple can also be determined, so that the inclination of the nipple can be determined. Obviously, the orientation of the reflecting surface with respect to the axis of rotation may be fixed or variable. In addition, in this case, the orientation of the axis of rotation may also be variable.

When the reflector is constituted by a pentagon having five reflecting surfaces, it seems that the position of the nipple can be determined optimally.

A particularly accurate determination of not only the position but also the inclination is obtained when one of the reflecting surfaces is parallel to the axis of rotation, two of the reflecting surfaces are at equal positive angles with respect to the axis of rotation, and the remaining two reflecting surfaces are at equal negative angles with respect to the axis of rotation. Thus, three detection surfaces are obtained, the outer surface being created by the rays or bundles of rays emanating from the two reflection surfaces and thus providing a double measurement. The positive and negative angles are preferably between approximately 3 ° and approximately 13 °.

Alternatively, a particularly accurate determination of the position and inclination is obtained when two of the reflecting surfaces are parallel to the rotation axis, one of the reflecting surfaces is at a first angle with respect to the rotation axis and the remaining two reflecting surfaces are at a second angle with respect to the rotation axis.

The first angle is preferably between approximately 1 ° and approximately 7 °. The second angle is preferably between approximately 1 ° and approximately 20 °. Accurate data is obtained, in particular, when the second angle is at least approximately twice as large as the first angle.

In order to accurately determine the position of two teats arranged behind each other with respect to the apparatus, the apparatus further comprises means for scanning at least two sub-areas of the space substantially simultaneously. This is preferably achieved by: the device is provided with means for directing at least two separate rays or ray bundles to different areas in the space.

A processor that processes data obtained from the two transmitter elements is sufficient when the transmitter elements are alternately activated and deactivated.

In order to obtain a simplified assembly of the device, the transmitter element, the receiver element and the directional element are mounted on a base plate to form a unit. The device is then assembled by housing the base plate containing the elements in a housing having a window through which the radiation or radiation beam emitted from the emitter element and/or from the nipple is transmitted, shock absorbing means being provided between the housing and the base plate. Thus, vibrations applied to the housing are not transmitted or transmitted to a lesser extent to sensitive parts of the device.

To prevent undesired reflections, the window is designed as a flat window and is angled with respect to the normal on the base plate.

The device is preferably provided with a dust detector for detecting contamination of the window. When a contaminant is detected, the dust detector may provide a signal to an operator of the device or an automated means for cleaning the window. Such a dust detector may be constituted by a separate receiver element for detecting the radiation or radiation beam reflected by the window.

The device is preferably provided with anti-condensation means for preventing and/or eliminating and/or reducing condensation on the inside of the window, so that the radiation or radiation beam is not affected when passing through the window. The anti-condensation device preferably comprises a heating element integrated into the window. The heating element is in particular continuously active, in other words independent of the ambient conditions. Thereby, independent of rapidly changing environmental conditions, no condensation of the reflective surface occurs at all times, which enhances the determination of the position.

The invention therefore also relates to a device for determining the position of a teat of an animal relative to the device, which device is provided with an emitter element for emitting a ray or a bundle of rays; at least one receiver element arranged for receiving the radiation or radiation beam reflected by the nipple; and at least one reflective surface which is rotatable about an axis of rotation for continuously guiding the radiation or radiation beam emanating from the emitter element to the teat and/or for guiding the radiation or radiation beam emanating from the teat to the receiver element, characterized in that the device comprises a housing having a window through which the radiation or radiation beam emanating from the emitter element and/or emanating from the teat is transmitted, the device being provided with a heating element integrated into the window, which heating element functions continuously, in other words independently of the ambient conditions.

A further protection against moisture is obtained in the housing when the inside of the wall of the housing is provided with an aluminium coating in addition to the window.

The device according to the invention is particularly suitable for use in a milking arrangement for milking animals, such as cows, provided with at least one milking parlour comprising at least one milking robot having a robot arm for automatically connecting a teat cup to a teat of the animal to be milked, for determining the position of the teat relative to the teat cup.

When the housing is covered by a cover supported by the robot arm, a milking device is obtained in which the means for determining the position of the teat are arranged in a shock-proof manner. The cover is preferably made of stainless steel.

Drawings

The invention will be explained in further detail by means of non-limiting exemplary embodiments with reference to the attached drawings, in which:

fig. 1 is a schematic cross-sectional view of an embodiment of a device according to the invention;

FIG. 2 is a schematic plan view of the apparatus shown in FIG. 1; and

fig. 3 is a schematic view of a part of a milking device provided with a device according to fig. 1 and 2.

Detailed Description

The embodiment shown in fig. 1 and 2 comprises a housing 1 having a side wall and a bottom made of a material that is not permeable to the relevant rays or ray bundles, such as a material that is light-proof (e.g. laser (IR-) light), said housing having an aperture or window at the front side, which aperture or window is sealed with a plate that is permeable to the relevant rays or ray bundles, such as a glass plate 2. The plate may also be made of, for example, a suitable synthetic material. Behind the glass plate 2, a directional element in the form of a mirror with a reflecting surface is arranged, which reflects the relevant ray or bundle of rays. According to an aspect of the invention, one reflecting surface is sufficient when means are provided for changing the orientation of the reflecting surface relative to the object. This can be achieved, for example, by mounting the axis of rotation 4 in bearings that reciprocate in directions toward and away from the window. Such movement may be achieved, for example, by an eccentric or a curved disk. The invention is described below with respect to a mirror in the form of a polygon 3 having at least three reflecting surfaces, which reflect the relevant rays or ray bundles. The polygon 3 is in particular constituted by a pentagon having five reflecting surfaces.

The polygon 3 is arranged so as to be rotatable about its axis of rotation 4 and is for this purpose bearing-supported at one side by means of a shaft end 5 in a bearing 6 in a bottom plate 7. A lid 8, preferably made of stainless steel, closes the housing 1. In this embodiment, the polygon 3 is driven directly via a stepper motor 9. The polygon 3 is preferably continuously rotated in the same direction at an at least substantially constant speed, so that its drive is lightly loaded and less prone to wear.

As schematically shown in fig. 2, on both sides of the polygon 3, a first emitter element 13 and a second emitter element 14 in the form of laser diodes are arranged, respectively. Below each first and second transmitter element 13, 14, a respective first and second receiver element 18, 17, here designed as a so-called CCD, is arranged. The wavelengths of the two diodes are preferably in the range of 600-900nm, more preferably in the range of 780-830nm, the wavelengths of the first emitter element 13 and the second emitter element 14 preferably being different from each other such that no interference occurs when the radiation or radiation beams 16 emitted from the first emitter element 13 and the second emitter element 14 cross each other. In addition, the wavelength difference is such that the sensitivity of the first receiver element 18 and the second receiver element 17 can be adjusted in a reliable manner in accordance with the radiation or radiation beam 16 emitted from the first transmitter element 13 and the second transmitter element 14, in order to prevent disturbances as far as possible in this respect as well. Alternatively, instead of the wavelength, the transmission amplitude between the first transmitter element 13 and the second transmitter element 14 may also be different. There may also be differences in the modulation of the transmitted signal. Furthermore, radiation or radiation beams 16 emitted from different heights of the first emitter element 13 and the second emitter element 14 can also be guided through the housing 1 such that they impinge on the directional element 3 in a further height region, whereby interference is also prevented. Other differences in characteristics of the two rays or beams 16 may also be used to counteract adverse interference effects, for example by using a combination of two or more of the above measures.

The first receiver element 18 and the second receiver element 17 are preferably constituted by diode sensors. In this case, the receiver element may have a one-dimensional or two-dimensional series of adjacent detector elements. Each detector element is sensitive to the respective radiation and, in case of exposure to said radiation, provides a detection signal corresponding to the intensity of said radiation to the evaluation device 10. Each first receiver element 18 and second receiver element 17 is attached to the base plate 7.

When the lasers are separately activated and deactivated, the ability to evaluate the device 10 is still limited, but the position can nevertheless be accurately determined. Thus, the evaluation device 10 only processes data from one of the lasers at a time.

In this case, the directional element 3 is shared by two rays or beams.

After leaving the respective first and second emitter elements 13, 14, the substantially emitted rays or ray bundles parallel to each other strike the respective deflection elements 19, 20 to be deflected towards the directional element 3, which is arranged between said deflection elements 19, 20. In this case, each deflection element is formed by a reflector 19, 20 which is at an angle of approximately 30 ° to the incident radiation or ray bundle 16. Alternatively, it is also possible to use, for example, corresponding prisms or glass fiber cable bundles.

Between each deflection element 19, 20 and the respective first receiver element 18 and second receiver element 17, a focusing element or converging element (in this embodiment, constituted by lenses 24, 25) is arranged, the function of which will be explained below. The directional element is adapted to direct each ray or beam 16 across a respective angular sector 22, 23 into a space to determine, for example, the position of a teat 21 of an animal to be milked in said space. In the case of a pentagon with five reflecting surfaces and two lasers each covering a sector, the angle of each angular sector 22, 23 is approximately 72 °. Each angular sector 22 and 23 may coincide with each other, for example by 2 °, so that the total angular area 29 to be scanned in the space amounts to 140 °. Since each ray or beam 16 is formed of a laser, the angular sector (perpendicular to its plane) is at least substantially non-divergent, except for some scattered radiation.

Radiation reflected from the space, or scattered radiation of the ray or ray bundle 16, is received by the directional element 3 as a reflected beam 27 and directed via the respective deflection elements 19, 20 to the first and second receiver elements 18, 17. The reflected beams 26, 27 are then transmitted through respective lenses 24, 25 such that a relatively wide reflected beam 27 is focused on a localized area of the receiver element. Since in this embodiment the lenses 24, 25 have a fixed focal length and are angled with respect to the robot arm as shown in fig. 3, and also since the lenses 24, 25 are attached to the base plate 7 and are thus fixedly arranged with respect to the respective first and second receiver elements 18, 17, the place where the nipple 21 is projected on the first and second receiver elements 18, 17 is related to the position of the nipple 21 in space. The first receiver element 18 and the second receiver element 17 provide respective signals to the evaluation means 10 (also attached to the base plate 7), for example constituted by a microprocessor, depending on the nature of the signals and their further processing, possibly by the intervention of an analog-to-digital converter. The principle of scanning the nipple 21 by successively directing rays or ray bundles to different areas in space, and the processing of the signals obtained by the sensor means, is known per se.

By updating the position of the directional element 3, for example by connecting the motor 9 to a pulse generator which generates a pulse every part of a revolution (for example every 1 °, obtained for example by simple calculations in a microprocessor), it is possible to deduce the position of the directional element 3 at the moment when the radiation or beam reflected by the nipple 21 hits the second receiver element 17. When the nipple 21 is located in another angular sector 22, a ray or beam of rays will of course emanate from the second transmitter element 14 and impinge on the second receiver element 17. In order to determine the zero position of the polygon, the polygon is provided with a position indicator, for example a protrusion 11, the position of which is determined by a detector 12, which is constituted, for example, by a light detector. When the protrusion 11 passes along the detector 12, a signal is provided to the evaluation device 10. The signal from the detector 12 may also be used for security purposes. For example, when the detector 12 does not detect the passage of a protrusion during a preset period of time, it may be assumed that the polygon 3 is rotated and then automatically deactivating the laser will improve safety.

For example, to detect dust on the window 2, one or both of the rays or beams 16 may be directed such that at a predetermined position of the directional element 3, no rays or beams 16 leaving the device are returned via the directional element 3 to (possibly) additional (not shown) receiver elements, so that contamination (if any) may be measured.

As shown in fig. 1, the glass plate 2 is positioned such that the normal on the glass plate 2 and the emitted radiation 16 form an angle for counteracting the unwanted reflections as much as possible.

As schematically shown in fig. 3, three position determining surfaces 28, 29, 30 are created, because one of the reflecting surfaces of the pentagon 3 is parallel to the rotation axis 4, two of the reflecting surfaces are at equal positive angles with respect to the rotation axis 4 and the remaining two reflecting surfaces are at equal negative angles with respect to the rotation axis 4. By means of these three surfaces 28, 29, 30, the position of the nipple 21 and at the same time its inclination can be determined more accurately. It is obvious that the invention is not limited to the generation of three position determining surfaces, but that the position can already be determined accurately with two (or more than three) position determining surfaces. However, it has proven sufficient to use three position determination surfaces. Furthermore, the number of reflecting surfaces produced by the position determining surface is adjustable as required. For example, for three position determining surfaces, three reflecting surfaces are sufficient. The invention therefore provides in all aspects the possibility of generating at least two spaced apart position-determining surfaces by means of one single emitter element, the radiation or radiation beams emitted by the two emitter elements together covering the space to be scanned on the nipple. In this way, the position of the teat in the sub-area a can be measured by one transmitter element and the position of the teat in the sub-area B by another transmitter element at the same time.

The positive and negative angles are between approximately 3 ° and approximately 13 ° taking into account the conventional distance between the nipples and the size of the nipples.

In an alternative embodiment, in which three position determining surfaces 28, 29, 30 are also created, two of the reflecting surfaces are parallel to the rotation axis, one of the reflecting surfaces is at a first angle relative to the rotation axis and the remaining two reflecting surfaces are at a second angle relative to the rotation axis. In this case, the first angle is between approximately 1 ° and approximately 7 °, and the second angle is between approximately 1 ° and approximately 20 °. The second angle is preferably at least approximately twice as large as the first angle, the second angle is preferably approximately 5.2 °, and the first angle is preferably approximately 2.6 °.

Since the bottom plate 7 carries the relevant elements of the device, said bottom plate containing the elements can be easily assembled in the housing 1. Between the housing 1 and the bottom plate 7 a shock absorbing means 15, such as a rubber ring, is arranged.

The device is preferably provided (not shown) with anti-condensation means for preventing and/or eliminating and/or reducing condensation on the inside of the window, so that the radiation or radiation beam is not affected when passing through the window. The anti-condensation device preferably comprises a heating element which is integrated into the window and functions continuously, in other words independently of the ambient conditions.

A further protection against moisture is obtained in the housing when the inside of the wall of the housing is provided with an aluminium coating, except for the window.

Fig. 3 schematically shows a part of a milking device provided with a device according to fig. 1 and 2. The milking arrangement is provided with at least one milking parlour comprising at least one milking robot having a robot arm 31 for automatically connecting teat cups 32 to teats of an animal to be milked. The scanning device 26 for determining the position of the teat relative to one of the teat cups 32 comprises a device as described with reference to fig. 1 and 2. The scanning device is angled with respect to the longitudinal direction of the robot arm 31, so that the position can be determined in a simple manner based on known triangulation principles.

Since the cover 8 is supported by the robot arm 31, the scanning device 26 for determining the position of the nipple is arranged to be shock-proof. The cover is preferably made of stainless steel.

Claims (14)

1. An apparatus for determining the spatial position of a teat (21) of an animal, the apparatus being provided with: a first emitter element (13) for emitting a first ray or beam (27) of radiation into a first sub-region (A) of space; and a second emitter element (14), distinct from the first emitter element (13), for emitting a second ray or beam of rays towards a second sub-area (B) of space, the first and second sub-areas (a, B) together constituting the space; a first receiver element (18) arranged for receiving a reflection of the first ray or ray bundle (27); a second receiver element (17) different from the first receiver element and arranged for receiving a reflection of the second ray or ray bundle; a single mirror which is rotatable about a rotation axis (4) for directing rays or ray bundles emitted from the first and second emitter elements into the relevant plane of the relevant sub-area of the space and/or for directing rays or ray bundles reflected from the relevant sub-area of the space into the relevant receiver element, characterized in that the device is provided with means for directing rays or ray bundles emitted from the first and second emitter elements into at least two spaced apart relevant position determining surfaces of the relevant sub-area of the space.

2. The arrangement as claimed in claim 1, characterized in that the mirror is formed by a polygon having at least two reflecting surfaces, at least one of which is angled differently with respect to the axis of rotation (4) than one of the remaining reflecting surfaces.

3. An apparatus as claimed in claim 1, characterized in that the apparatus is provided with means for directing the radiation or radiation beams emanating from the first emitter element and the second emitter element into three spaced apart relevant position-determining surfaces of the relevant sub-area of space.

4. The apparatus of claim 3, wherein the mirror is formed by a pentagon having five reflective surfaces, one of which is parallel to the axis of rotation, two of which are at equal positive angles with respect to the axis of rotation, and the remaining two of which are at equal negative angles with respect to the axis of rotation.

5. The apparatus of claim 4, wherein the positive and negative angles are between 3 ° and 13 °.

6. The device according to claim 4, wherein two of the five reflective surfaces are parallel to the rotation axis (4), one of the five reflective surfaces is at a first angle with respect to the rotation axis (4), and the remaining two of the five reflective surfaces are at a second angle with respect to the rotation axis (4).

7. The device of claim 6, wherein the first angle is between 1 ° and 7 °.

8. The device of claim 6 or 7, wherein the second angle is between 1 ° and 20 °.

9. The apparatus of claim 6 or 7, wherein the second angle is at least twice as large as the first angle.

10. An apparatus as claimed in claim 2, wherein means are provided for changing the orientation of the at least two reflective surfaces relative to the teat during rotation of the at least two reflective surfaces.

11. An arrangement according to claim 10, characterized in that said means are adapted to change the orientation of said at least two reflecting surfaces with respect to said axis of rotation (4).

12. The device according to claim 10 or 11, characterized in that the means are adapted to change the orientation of the axis of rotation (4).

13. An apparatus as claimed in claim 10, characterized in that the apparatus comprises means for scanning at least two sub-regions of the space simultaneously.

14. A milking arrangement for milking an animal, the milking arrangement being provided with: at least one milking parlour comprising at least one milking robot having a robot arm for automatically connecting teat cups to teats of an animal to be milked; and a scanning device for determining the position of a teat relative to a teat cup, characterized in that the scanning device comprises a device for determining the spatial position of a teat (21) of an animal according to any of the preceding claims 1-13.

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