Method and device for inspecting the abdominal cavity of eviscerated fish

Description

[0001] The present invention relates to a method for the optical inspection of gutted fish with an open abdominal cavity. Furthermore, the invention relates to a method for gutting fish that are conveyed longitudinally along a processing line by means of a conveyor device.

[0002] Furthermore, the invention relates to a device for optically inspecting the opened abdominal cavity of eviscerated fish and to a device for eviscerating fish which are conveyed along a processing line in the longitudinal direction by means of a conveyor device.

[0003] Such devices and methods are used in industrial fish processing. Typically, the fish are slaughtered automatically by opening the abdominal cavity and automatically removing the viscera using appropriate tools. The evisceration results are usually visually inspected. For this purpose, the abdominal cavity of the fish is inspected with a color camera following the evisceration step, and the captured image of the abdominal cavity is examined for possible remaining blood and / or visceral residues using well-known image processing algorithms. Such devices and methods are known, for example, from "Gutmaster 3000 - The perfect gutting machine for medium-sized fish" and "Visiomaster - The good result is now visible."

[0004] These known devices and methods have a number of disadvantages. Due to the use of a color camera, which splits the incoming light into its primary colors using a Bayer filter, the effective resolution is significantly reduced compared to a monochrome camera. Furthermore, correspondingly long exposure times are required. This prevents the fish from being transported at the highest possible speed, as the maximum transport speed is severely limited due to the exposure time required. Increasing the transport speed leads to blurred images of the abdominal cavity and thus to an overall low reliability of the image analysis. A further disadvantage is that color image analysis is computationally and therefore time-intensive.

[0005] The object of the present invention is therefore to propose a device and a method that ensure reliable visual inspection of the abdominal cavity while simultaneously achieving the highest possible conveying speeds for the fish. Furthermore, the object is to propose a device and a method for eviscerating fish that enable the most reliable evisceration results possible at high conveying speeds.

[0006] The object is achieved by the device mentioned at the outset, wherein the device comprises a conveyor device configured to convey the fish in the longitudinal direction along a processing line, pivotable abdominal flap holding elements configured to hold the abdominal cavity of the fish, at least one optical imager arranged along the processing line, which is designed and configured to record at least one image sequence comprising several individual images of abdominal cavity regions of one of the fish, at least one lighting device configured to illuminate the abdominal cavity regions at the recording times of the individual images with light of a predetermined spectral composition, an evaluation unit configured to evaluate the image sequence with regard to predetermined quality parameters, which is configured to control an ejection device if the evaluation reveals a deviation from the predetermined quality parameters,to remove the respective fish from the processing line by discharging them. This offers the advantage that the abdominal cavity areas are illuminated by the lighting devices with a predetermined light color or wavelength range, and the individual images are recorded by one of the optical imagers. By illuminating with colored light, the wavelength range of interest is recorded by the optical imagers. A color filter, such as a Bayer filter or the like, is no longer required in the optical imager. This benefits the overall resolution of the respective optical imagers, and the intensity of the incident light is not attenuated by any filters. This favors short exposure times, so that the fish can be transported at correspondingly high conveyor speeds. A further advantage isthat, due to the active illumination by means of the illumination devices, the fish or its abdominal cavity can be illuminated with high-intensity light. The illumination devices are preferably formed from LED arrays. The illumination devices are further preferably operated only for the duration of the required exposure time, so that the areas to be illuminated are illuminated in a flash. The present invention is therefore particularly suitable for the optical inspection of rapidly moving objects.

[0007] An advantageous development of the invention is characterized in that the at least one illumination device is configured to illuminate the abdominal cavity region with light from different spectral ranges at each recording time. This makes it possible to inspect the abdominal cavity of the fish in an optimally adapted manner according to any desired quality characteristics. Preferably, the light spectral ranges used are tailored to the respective structures to be detected. The actual evaluation of the image sequence is carried out using conventional image evaluation algorithms based either on statistical methods or on the application of neural networks.

[0008] According to a preferred embodiment, the at least one illumination device comprises a light source configured to emit light with a narrowband spectrum. This further increases the selectivity for detecting specific structures.

[0009] According to the invention, the device comprises further control means designed and configured to control the at least one optical imager such that the temporal interval between the recordings of two consecutive individual images of one of the image sequences is selected such that the two consecutive individual images depict at least substantially the same abdominal cavity region. This has a particularly advantageous effect on the complexity of image analysis. Due to the now possible short temporal interval between the recordings, the continuous movement of the respective fish does not lead to a spatial displacement of the individual images. An otherwise necessary correction - "mapping" - of the image position in order to align the individual images can therefore be eliminated. This has a positive effect on the computing time required to evaluate the image sequence.

[0010] According to the invention, several optical imagers are arranged separately along the processing line and configured to capture each of the individual images with one of the optical imagers. This ensures reliable inspection at all times, even at high conveyor speeds.

[0011] According to an advantageous embodiment of the invention, each of the optical imagers is assigned a separate illumination device configured to illuminate the abdominal cavity regions at the respective acquisition times. As already mentioned, this allows the corresponding regions and structures to be examined with high detection accuracy.

[0012] A further advantageous embodiment is characterized by the fact that the at least one optical imager is designed as a black-and-white camera. The use of black-and-white cameras enables high-resolution images and thus a correspondingly high degree of accuracy in the abdominal cavity inspection. Furthermore, they are sufficiently light-sensitive, allowing the aforementioned short exposure times and high conveying speeds to be achieved.

[0013] According to a further preferred embodiment, the at least one optical imager is arranged such that at least one of the individual images is captured with a perpendicular or at least substantially perpendicular view of the abdominal cavity. This allows the entire area of ​​the abdominal cavity to be optimally illuminated and any remaining remnants to be reliably detected.

[0014] A further embodiment of the invention provides that at least one additional optical imager is arranged such that at least one additional individual image is captured with a viewing direction inclined relative to the vertical viewing direction. This enables the detection of areas that are shadowed by vertical illumination, thus increasing the overall detection quality and thus the reliability of the abdominal cavity inspection.

[0015] Advantageously, the at least one additional optical imager is arranged at an angle such that the image is captured in the angled viewing direction, in the direction of the fish's head. In other words, an oblique image is captured with a view from the tail to the head. In addition to the aforementioned advantage of inspecting shadowed areas, this offers the additional benefit of also being able to explicitly inspect the head-side region of the abdominal cavity.

[0016] According to a preferred embodiment of the invention, the evaluation unit is configured to superimpose the individual images of the image sequence into an overall image. The overall image serves, for example, as a control image for spot-checking the inspection process. Alternatively, the overall image is used as a starting point for the optical inspection.

[0017] The object is also achieved by the device for gutting fish mentioned above, wherein the fish are conveyed along a processing line in the longitudinal direction by means of a conveyor device comprising opening tools designed to open the abdominal cavity of the fish, gutting tools designed to clean the abdominal cavity, and a device for the subsequent visual inspection of the abdominal cavity of the gutted fish as described above. The combination of the inventive method for the visual inspection of the abdominal cavity and the upstream gutting process ensures a high-quality production process, ensuring that the fish meet the quality requirements for a clean abdominal cavity after the gutting process.

[0018] Furthermore, the object is achieved by the method mentioned at the outset, comprising conveying the fish in the longitudinal direction along a processing line by means of a conveyor device, pivoting in abdominal flap holding elements designed to hold the abdominal cavity of the fish, recording at least one image sequence comprising a plurality of individual images of abdominal cavity regions of one of the fish by means of at least one optical imager arranged along the processing line, illuminating the abdominal cavity regions at the recording times of the individual images by means of at least one illumination device with light of a respective predetermined spectral composition, evaluating the image sequence with regard to predetermined quality parameters and, if the evaluation reveals a deviation from the predetermined quality parameters, removing the respective fish from the processing line by discharging it by means of a discharging device.

[0019] The advantages associated with the method according to the invention have already been explained in detail in connection with the device according to the invention. To avoid repetition, reference is made to the relevant text passages. This also applies to the preferred embodiments of the method according to the invention mentioned below.

[0020] A preferred embodiment of the invention is characterized in that the illumination at each recording time is performed with light from different spectral ranges. Preferably, the illumination is performed with light from a narrow-band spectrum.

[0021] According to the invention, the time interval between the recording of two consecutive individual images of one of the image sequences is selected such that the two consecutive individual images depict at least substantially the same abdominal cavity region.

[0022] According to the invention, each of the individual images is recorded with a separate optical imager.

[0023] Advantageously, each of the optical imagers is assigned a separate illumination device by means of which the illumination is provided at the respective recording times.

[0024] A preferred embodiment of the invention is characterized in that the individual images are recorded in black and white.

[0025] According to an advantageous embodiment of the invention, at least one of the individual images is recorded with one of the optical imagers with a vertical or at least substantially vertical viewing direction onto the abdominal cavity.

[0026] It is further preferred that at least one additional individual image be captured with another of the optical imagers with a viewing direction inclined relative to the vertical viewing direction. In particular, it is advantageous that the image be captured in the inclined viewing direction in the direction of the fish's head.

[0027] A preferred embodiment of the invention provides for individual images of the image sequence to be superimposed to form an overall image.

[0028] The object is further achieved by the method mentioned at the outset for eviscerating fish which are conveyed along a processing line in the longitudinal direction by means of a conveyor device, wherein the method comprises opening the abdominal cavity of the fish, clearing the abdominal cavity by means of eviscerating tools and subsequently optically inspecting the abdominal cavity of the eviscerated fish by means of the method described above.

[0029] Further preferred and / or expedient features and embodiments of the invention emerge from the dependent claims and the description. Particularly preferred embodiments are explained in more detail with reference to the accompanying drawings. The drawing shows: Fig. 1 is a schematic representation of the device according to the invention in side view, Fig. 2 is a schematic representation of a first method step according to the invention in detail, Fig. 3 is a schematic representation of a second method step according to the invention in detail, Fig. 4 is a schematic detailed view with an abdominal flap holding element in a waiting position of the device according to the invention in side view, Fig. 5 is a schematic detailed view with an abdominal flap holding element in a working position of the device according to the invention in side view, Fig. 6 is a perspective view of the in Fig. 4 shown detailed view and Fig. 7 a perspective view of the Fig.5detailed view shown.

[0030] The device according to the invention and the method according to the invention are described in more detail below with reference to the drawing. To avoid repetition, the method according to the invention is also explained using the device according to the invention. The statements made regarding the device therefore also apply analogously to the method according to the invention.

[0031] In the Figure 1a schematic representation of the device according to the invention is shown in side view. The device is designed and configured for the visual inspection of the opened abdominal cavity 10 of eviscerated fish 11. The device comprises a conveyor device 12 configured to convey the fish 11 in the longitudinal direction 13 along a processing line. The conveyor device 12 is designed, for example, as a circulating conveyor belt 14 with holding and centering means 15. The holding and centering means 15 are configured to hold the fish 11 in a supine position and to align them so that they are conveyed in the longitudinal direction 13 with the opened abdominal cavity 10 pointing upwards. The holding and centering means 15 are preferably V-shaped. One of the holding and centering means is designed as a tail clamp 16, which secures the respective fish 11 against slipping in the longitudinal direction 13.

[0032] The device according to the invention further comprises pivotable abdominal flap holding elements 17 designed to hold the abdominal cavity 10 of the fish open. The abdominal flap holding elements 17 preferably comprise a substantially V-shaped spreader bar 18, which is moved into and out of the abdominal cavity 10 via a pivoting lever 19. The abdominal flap holding elements 17 are designed and constructed to spread apart the abdominal flaps of the opened abdominal cavity 10 of the fish 11.

[0033] At least one optical imager is arranged on the processing line, for example - as in Figure 1shown - a first imager 21, a second imager 22, and a third imager 23. However, the present invention is not limited to the number of imagers 21, 22, 23 shown, but may alternatively comprise fewer or more of the imagers 21, 22, 23. The imagers 21, 22, 23 are designed and configured to record at least one image sequence comprising several individual images of abdominal cavity regions of one of the fish 11.

[0034] By means of a first illumination device 24 and a second illumination device 25, the abdominal cavity regions are illuminated with light of a predetermined spectral composition at the time of recording of the individual images. The number of illumination devices is not - as in Figure 1shown - limited to only two. Alternatively, it is also possible to use only one of the lighting devices 24, 25 or to use more than two of the lighting devices 24, 25.

[0035] An evaluation unit 26 is configured and designed to evaluate the image sequence with respect to predefined quality parameters. If the evaluation reveals a deviation from the predefined quality parameters, it is designed to control an ejection device (not shown in the drawing) to remove the respective fish 11 from the processing line. The predefined quality parameters refer, for example, to optical comparison values ​​that provide information about the extent to which the entrails have already been removed. This also includes comparison values ​​relating to blood residues or connective tissue residues. Furthermore, the quality parameters include variables for verifying the correct position of the abdominal incision.

[0036] The evaluation unit 26 is connected to the optical imagers 21, 22, 23, the first and second illumination devices 24, 25, an actuator 27 for moving the abdominal flap holding elements 17, and preferably to a drive 31 for driving the conveyor device 12, so that the evaluation unit 26 can control or regulate the aforementioned components. The connections are preferably designed as electrical connections.

[0037] The first illumination device 24 and the second illumination device 25 are each configured to illuminate the abdominal cavity region at the acquisition times with light from different spectral ranges. The spectral ranges each encompass a section of the visible and infrared wavelength spectrum, respectively.

[0038] Preferably, the first illumination device 24 and the second illumination device 25 each comprise a light source configured to emit light within a narrowband spectrum. Narrowband means that the light covers a spectral range with a wavelength of less than 100 nm. Particularly preferably, the light is monochromatic.

[0039] The evaluation unit 26 further comprises control means designed and configured to control the image generators 21, 22, 23 such that the temporal interval between the recordings of two consecutive individual images of one of the image sequences is selected such that the two consecutive individual images depict at least substantially the same abdominal cavity region. In other words, the control means are configured, in coordination with the set conveying speed of the conveying device 12, to record the individual images at such a temporal interval that the respective individual images depict substantially the same region of the abdominal cavity 10.

[0040] As can be seen from the Figures 2 and 3 As can be seen, several of the optical imagers 21, 22, 23 are arranged along the processing line, whereby in the detailed views of the Figures 2 and 3only the first imager 21 and the third imager 23 are shown. The optical imagers 21, 22, 23 are preferably arranged separately and configured to record each of the individual images with one of the optical imagers 21, 22, 23. For reasons of better overview, the abdominal flap holding elements 17, which keep the abdominal cavity 10 of the respective fish 11 open for optical inspection, are shown in the Figures 2 and 3 not shown.

[0041] Particularly preferably, each of the optical imagers 21, 22, 23 is assigned a separate illumination device, which is configured to illuminate the abdominal cavity regions at the respective recording times. As shown in the Figures 2 and 3 As shown, the first illumination device 24 is assigned to the first image generator 21 and the second illumination device 25 is assigned to the third image generator 23.

[0042] According to an advantageous embodiment of the invention, the imagers 21, 22, 23 are each designed as a black-and-white camera or a monochrome camera. Alternatively, one or more of the imagers 21, 22, 23 are each designed as a color camera.

[0043] Preferably, at least one of the optical imagers 21, 22, 23 is arranged such that at least one of the individual images is recorded with a perpendicular or at least substantially perpendicular viewing direction onto the abdominal cavity 10. For this purpose, for example, the first imager 21 and the first illumination device 24 - as in Figure 2 shown - arranged above the conveyor device 12.

[0044] As in Figure 3As shown, at least one further optical imager, for example the third imager 23, is arranged such that at least one further individual image is recorded with a viewing direction inclined relative to the vertical viewing direction. In particular, the third imager 23 is arranged at an inclination such that the recording is made in the inclined viewing direction in the direction of the fish's head.

[0045] The evaluation unit 26 is particularly configured to superimpose the individual images of the image sequence into an overall image. The overall image can optionally be displayed for control purposes. Furthermore, the overall image is used for quality control. The evaluation unit 26 is preferably configured to combine the image sequence into a false-color image by applying different weightings to the individual images.

[0046] In particular, the imagers 21, 22, 23 and the illumination devices 24, 25 are preferably encapsulated in a housing 28 with at least one viewing window 30.

[0047] In the Figure 5 A schematic detail view of the abdominal flap holding elements 17 in a working position of the device according to the invention is shown in a side view. The abdominal flap holding elements 17 are guided into the abdominal cavity and hold the abdominal flaps 20 open at the sides so that the abdominal cavity can be inspected. Figure 4 is shown how the abdominal flap holding elements 17 are in a waiting position outside the abdominal cavity.

[0048] The Figures 6 and 7 each show a perspective view of the detailed views of the Figures 4 and 5 . The Figures 4 to 7 each show a centering aid 29, by means of which the fish 11 are guided laterally and thus centered in the middle.

[0049] The present invention further comprises a device for eviscerating fish 11, which are conveyed along a processing line in the longitudinal direction 13 by means of the conveyor device 12. The device comprises opening tools configured to open the abdominal cavity 10 of the fish 11, eviscerating tools configured to empty the abdominal cavity 10, and a device for the subsequent visual inspection of the abdominal cavity 10 of the eviscerated fish 11, as described above. Such devices for opening the abdominal cavity and the eviscerating tools are known, for example, from documents EP 1003378 A1 and EP 1411775 and are therefore not described in further detail.

Claims

1. Method for the optical inspection of gutted fish (11) with opened abdominal cavity (10), comprising conveying the fish (11) along a processing line in the longitudinal direction (13) by means of a conveyor device (12), pivoting of ventral flaps holding elements (17) configured for holding open the abdominal cavity (10) of the fish (11), taking of at least one sequence of images of abdominal cavity regions of one of the fish (11) in each case, said image sequence comprising a plurality of single images taken using at least one optical imaging system (21, 22, 23) arranged along the processing line, illuminating the abdominal cavity regions with light of in each case a predetermined spectral composition by means of at least one illumination device (24, 25), in each case at the times the single images are taken, evaluating the image sequence according to prescribed quality parameters and removal of the relevant fish (11) from the processing line by ejecting it using an ejection device, should the evaluation reveal any deviation from the prescribed quality parameters, wherein each of the individual images is recorded with a separate optical imaging system (21, 22, 23), wherein the time interval between the two consecutive single images of one of the image sequences is chosen such that the two consecutive single images at least substantially illustrate the same abdominal cavity region.

2. Method according to claim 1, characterized in that the illumination takes place in each case with light of different spectral ranges at the times the images are taken.

3. Method according to claim 2, characterized in that the illumination takes place with light of a narrow-band spectrum.

4. Method according to claims 1 to 3, characterized in that each of the optical imaging systems (21, 22, 23) is assigned a separate illumination device (24, 25) by means of which the illumination takes place in each case at the times the images are taken.

5. Method according to one of claims 1 to 4, characterized in that the single images are taken in black and white.

6. Method according to any one of claims 1 to 5, characterized in that at least one of the single images is taken with one of the separate optical imaging systems (21, 22, 23) with a viewing direction onto the abdominal cavity (10) that is vertical or at least substantially vertical.

7. Method according to claim 6, characterized in that at least one other of the single images is taken with one other of the optical imaging system (23) with a viewing direction that is inclined in relation to the vertical viewing direction.

8. Method according to claim 7, characterized in that in the inclined viewing direction the images are taken towards the head of the fish (11).

9. Method according to any one of claims 2 to 8, characterized by overlaying the single images of the image sequence to create an overall image.

10. Method for gutting fish (11) which are conveyed along a processing line in the longitudinal direction (13) by means of a conveying device (12), opening of the abdominal cavity (10) of the fish (11), cleaning out of the abdominal cavity (10) by means of gutting tools and subsequent optical inspection of the abdominal cavity (10) of the gutted fish (11) by means of a method according to any one of claims 1 to 9.

11. Apparatus for optical inspection of the opened abdominal cavity (10) of gutted fish (11), comprising a conveying device (12) configured for conveying the fish (11) along a processing line in the longitudinal direction, pivotable ventral flaps holding elements (17) for holding open the abdominal cavity (10) of the fish, at least one optical imaging system (21, 22, 23) arranged along the processing line which is designed and configured to take at least one sequence of images of abdominal cavity regions of one of the fish (11) in each case, said image sequence comprising a plurality of single images, at least one illumination device (24, 25) configured for illuminating the abdominal cavity regions, in each case with light of a predetermined spectral composition, in each case at the times the single images are taken, an evaluation unit (26) configured to evaluate the image sequence according to prescribed quality parameters, said evaluation unit being designed to activate an ejection device to remove the relevant fish (11) from the processing line by ejecting it, should the evaluation reveal any deviation from the prescribed quality parameters, further comprising control means which are designed and configured to control the at least one optical imaging device (21, 22, 23) in such a way that the time interval between taking two consecutive single images of one of the image sequences is chosen such a way that the two consecutive single images at least substantially illustrate the same abdominal cavity region.

12. Apparatus according to claim 11, characterized in that the at least one illumination device (24, 25) is configured to illuminate the abdominal cavity region in each case with light of different spectral ranges, at the times the images are taken.

13. Apparatus according to claim 12, characterized in that the at least one illumination device (24, 25) comprises a light source which is configured to emit light of a narrow band spectrum.

14. Apparatus according to claim 11, characterized in that each of the optical imaging systems (21, 22, 23) is assigned a separate illumination means (24, 25) which is configured to illuminate the abdominal cavity regions in each case at the times the images are taken.

15. Apparatus according to any one of claims 11 to 14, characterized in that the at least one optical imaging system (21, 22, 23) is designed as a black-and-white camera.

16. Apparatus according to any one of claims 11 to 15, characterized in that the at least one optical imaging system (21, 22, 23) is arranged in such a manner that at least one of the single images is taken with a viewing direction onto the abdominal cavity (10) that is vertical or at least substantially vertical.

17. Apparatus according to claim 16, characterized in that at least one further optical imaging system (23) is arranged in such a manner that at least one other of the single images is taken with a viewing direction that is inclined in relation to the vertical viewing direction.

18. Apparatus according to claim 17, characterized in that the at least one further optical imaging system (23) is inclined in such a manner that in the inclined viewing direction the images are taken towards the head direction of the fish.

19. Apparatus according to any one of claims 11 to 18, characterized in that the evaluation unit (26) is configured to overlay the single images of the image sequence to create an overall image.

20. Apparatus for gutting fish (11) which are conveyed along a processing line in the longitudinal direction (13) by means of a conveying device (12), comprising opening tools configured for opening the abdominal cavity (10) of the fish, gutting tools designed for cleaning out the abdominal cavity (10) and an apparatus for subsequent optical inspection of the abdominal cavity (10) of the gutted fish (11) according to one of claims 11 to 19.