METHOD AND DEVICE FOR DETECTING A FLUID BY A COMPUTER VISION APPLICATION

Abstract

Described herein are a device and a method for recognizing and monitoring a fluid in a system and/or in surroundings of the system via a computer vision application, the device including at least the following components: at least one luminescent dye, each luminescent dye having a dye specific reflectance and luminescence spectral pattern and being configured to be added to the fluid, a light source which is composed of at least two illuminants and which is configured to illuminate a scene which includes the system and/or the surroundings of the system, by switching between the at least two illuminants, where at least one of the two illuminants is based on at least one solid-state system, a sensor which is configured to measure radiance data of the scene when the scene is illuminated by the light source, and a data processing unit.

Claims

1. A device for recognizing and monitoring a fluid in a system and/or in surroundings of the system via a computer vision application, the device comprising at least the following components: at least one luminescent dye, each luminescent dye having a dye specific reflectance and luminescence spectral pattern and being configured to be added to the fluid, a light source which is composed of at least two illuminants and which is configured to illuminate a scene which includes the system and/or the surroundings of the system, by switching between the at least two illuminants, wherein at least one of the two illuminants is based on at least one solid-state system, a sensor which is configured to measure radiance data of the scene when the scene is illuminated by the light source, and a data processing unit which is configured to determine whether the dye specific luminescence spectral pattern is detectable out of the radiance data of the scene when the scene is illuminated by the light source, and, in the case that the dye specific luminescence spectral pattern can be detected out of the radiance data, to identify the fluid the dye has been added to.

2. The device of claim 1 for monitoring the system for leaks via a computer vision application, the system using the fluid as operating medium which is to be carried continuously through the system, wherein the data processing unit is configured to determine whether the dye specific luminescence spectral pattern is extractable out of the radiance data of the scene when the scene is illuminated by the light source, and, in the case that the dye specific luminescence spectral pattern can be extracted out of the radiance data, to identify a leak of the system.

3. The device according to claim 1, further comprising an output unit which is configured to perform and/or initiate, in the case that the dye specific luminescence spectral pattern can be extracted out of the radiance data, a predefined action.

4. The device according to claim 1, which comprises a plurality of different dyes, the different dyes having different dye specific reflectance and luminescence spectral patterns and being configured to be added to the fluid in different fluid paths within the system, thus enabling, in the case that one of the dye specific luminescence spectral patterns can be extracted out of the radiance data, a localisation of the identified fluid, particularly of the identified leak in the case that the device is used for leak detection.

5. The device according to claim 1, which comprises a data storage unit with luminescence spectral patterns together with appropriately assigned respective dyes, wherein the data processing unit is configured to identify the dye specific luminescence spectral pattern of the at least one dye by matching the extracted dye specific luminescence spectral pattern with the luminescence spectral patterns stored in the data storage unit using any number of matching algorithms between the extracted dye specific luminescence spectral pattern and the stored luminescence spectral patterns.

6. The device according to claim 1, wherein the sensor is a hyperspectral camera or a multispectral camera.

7. The device according to claim 1, wherein the light source is a switchable light source with two illuminants each comprised of one or more LEDs and with a short switchover time between the two illuminants.

8. The device according to claim 1, wherein the sensor is synchronized to the switching of the light source to only issue at one time the radiance data from the scene and/or the surroundings of the scene under one of the at least two illuminants.

9. A method for recognizing and monitoring a fluid in a system and/or in surroundings of the system via a computer vision application, the method comprising at least the following steps: admixing a luminescent dye to the fluid, the luminescent dye having a dye specific reflectance and luminescence spectral pattern, illuminating a scene including the system and/or the surroundings of the system, preferably under ambient lighting conditions, with an additional light source which is composed of at least two illuminants, by switching between the at least two illuminants, wherein at least one of the two illuminants is based on at least one solid-state system, measuring, by means of a sensor, radiance data of the scene when the scene is illuminated by the light source, determining, by a data processing unit, whether the dye specific luminescence spectral pattern is detectable out of the radiance data of the scene, and in the case that the dye specific luminescence spectral pattern can be detected out of the radiance data, identifying, by the data processing unit, the fluid.

10. The method of claim 9 for monitoring the system for leaks via a computer vision application, the system using the fluid as operating medium which is to be carried continuously through the system, the method further comprising at least the following steps: determining, by the data processing unit, whether the dye specific luminescence spectral pattern is extractable out of the radiance data of the scene, and in the case that the dye specific luminescence spectral pattern can be extracted out of the radiance data, identifying, by the data processing unit, a leak of the system.

11. The method according to claim 9, further comprising providing a data storage unit with luminescence spectral patterns together with appropriately assigned respective dyes, and identifying the dye specific luminescence spectral pattern of the at least one dye by matching the extracted dye specific luminescence spectral pattern with the luminescence spectral patterns stored in the data storage unit using any number of matching algorithms between the extracted dye specific luminescence spectral pattern and the stored luminescence spectral patterns.

12. The method according to claim 9, further comprising initiating and/or performing, in the case that the dye specific luminescence spectral pattern can be extracted out of the radiance data, a predefined action.

13. The method according to claim 9, wherein a plurality of different dyes is provided, the different dyes having different dye specific reflectance and luminescence spectral patterns, and different dyes are admixed to the fluid in different fluid paths within the system, thus enabling, in the case that one of the dye specific luminescence spectral patterns can be extracted out of the radiance data, a localisation of the identified fluid.

14. The method according to claim 9, wherein the light source is chosen as a switchable light source with two illuminants each comprised of one or more LEDs and with a short switchover time between the two illuminants.

15. A computer program product having instructions for monitoring a fluid in a system and/or in surroundings of the system via a computer vision application, wherein the instructions are stored on a non-transitory computer-readable medium functionally coupled to one or more processors and cause, when executed on the one or more processors, a machine to: admix a luminescent dye to the fluid, the luminescent dye having a dye specific reflectance and luminescence spectral pattern, illuminate a scene which includes the system and/or the surroundings of the system, preferably under ambient lighting conditions, with an additional light source which is composed of at least two illuminants, by switching between the at least two illuminants, wherein at least one of the two illuminants is based on at least one solid-state system, measure, by means of a sensor, radiance data of the scene when the scene is illuminated by the light source, determine, by a data processing unit, whether the dye specific luminescence spectral pattern is detectable out of the radiance data of the scene, and in the case that the dye specific luminescence spectral pattern can be detected out of the radiance data, identifying, by the data processing unit, the fluid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0104] FIG. 1 shows schematically an embodiment of the proposed device executing an embodiment of the proposed method.

DETAILED DESCRIPTION OF THE DRAWINGS

[0105] FIG. 1 shows an embodiment of a device 100 for monitoring a system for leaks via a computer vision application. The system is represented here by a stove 110 which uses a fluid, namely a gas 105 as operating medium which is to be carried continuously through pipes of the stove 110. The device 100 for monitoring the stove 110 for leaks comprises a light source 101, a sensor 102, a data storage unit 104 and a data processing unit 103. The device 100 for monitoring the stove 110 for leaks further provides at least one luminescent dye 106, each luminescent dye having dye-specific reflectance and luminescence spectral patterns and being configured to be added to the gas 105. Further, a controller, not shown here, is provided in order to run the stove 110 to circulate the dye when being added to the gas throughout the stove 110, i.e. the pipes of the stove 110. The light source 101 is composed of at least two illuminants and is configured to illuminate a scene including the stove 110 and/or the surroundings of the stove 110 under ambient lighting conditions, by switching between the at least two illuminants wherein at least one of the two illuminants is based on at least one solid-state system. The at least one solid-state system may be chosen from the group of solid-state systems comprising semiconductor light emitting diodes (LEDs), organic light emitting diodes (OLEDs), or polymer light emitting diodes (PLEDs).

[0106] The data storage unit 104 stores and provides luminescence spectral patterns together with appropriately assigned respective dyes. The sensor 102 is configured to measure radiance data of the scene when the scene is illuminated by the light source 101. The scene includes here the surroundings of the stove 110, as indicated by the cone 111 (viewing field of the sensor 102) originating from the sensor 102. The sensor 102 is generally an optical sensor with photon counting capabilities. More specifically, it may be a monochrome camera or an RGB camera or a multispectral camera or a hyperspectral camera. The sensor 102 may also be a combination of any of the above, or a combination of any of the above with a tunable or selectable filter set, such as, for example, a monochrome sensor with specific filters. The sensor may measure a single pixel of the scene or measure many pixels at once. The optical sensor 102 may be configured to count photons in a specific range of spectrum, particularly in more than three bands. It may be a camera with multiple pixels for a large field of view, particularly simultaneously reading all bands or different bands at different times. In FIG. 1 the scene is defined by the cone 111 incorporating surroundings of the stove 110.

[0107] Up to now, fluorescent leak detection is commonly performed on hydraulic and refrigerant systems to more easily find the source of costly, performance degrading, and environmentally damaging leaks. Typically, a technician adds a fluorescent dye to the respective system, runs the system to circulate the dye throughout the entire system, and then checks the system for leaks by shining an appropriate light source (most often UV or blue light) on components of the system. If the ambient lighting is dark enough, leaks can be easily seen as the fluorescent dye in the system fluid will emit visible light where the leak is occurring. While this method known in the art is effective at finding leaks, it requires the presence of a technician and is not a continuously monitored process. Substantial benefits could be realized if the system is continuously monitored and the leak is automatically detected so appropriate measures, call for maintenance, partial or complete shutdown of the system, etc., could be initiated.

[0108] The proposed device according to the present disclosure pairs the technique to separate reflectance and fluorescence emission components under ambient light to automatic fluorescent leak detection. In many cases, systems such as the stove 110 that should be monitored for leaks are in an environment where bright lighting is required for other purposes. While it may be acceptable to temporarily dim these lights for a technician to inspect the system for leaks, continuous dimming of the lights as is currently required for computer vision detection of the fluorescent leak would be unacceptable. Therefore, the proposed device 100 provides the possibility to distinguish fluorescence emission from reflectance under ambient lighting conditions. By means of the proposed device 100 it is possible to match the detected fluorescence emission to a corresponding dye in the data storage unit 104 to facilitate dye identification for computer vision. It is possible that the device further comprises an output unit which is configured to output, in the case that the dye-specific luminescence spectral pattern can be detected out of the radiance data, a notification of the identified leak of the system 110. Such an output can be realized by a display and/or by an acoustic output, such as a loud speaker. It is possible that the device simply sends and/or outputs the signal when a certain level of fluorescence was detected and could be matched to a dye whose fluorescence pattern is stored in the data storage unit 104.

[0109] It is further possible that the device provides a plurality of different dyes, the different dyes having different dye-specific reflectance and luminescence spectral patterns and being configured to be added to the fluid in different fluid paths within the system 110, here the stove, thus enabling, in the case that one of the dye-specific luminescence spectral patterns can be detected out of the radiance data, the localization of the identified leak in the stove 110. The data processing unit 103 which matches the detected luminescent/luminescence spectral pattern with luminescence spectral patterns stored together with appropriately assigned respective dyes in the database 103, is configured to identify the dye-specific luminescence spectral pattern of the at least one dye by matching the detected dye-specific luminescence spectral pattern with the luminescence spectral patterns stored in the data storage unit 103 using any number of matching algorithms between the detected dye-specific luminescence spectral pattern and the stored luminescence spectral patterns. The matching algorithms may be chosen from the group comprising at least one of: lowest root means squared error, lowest mean absolute error, highest coefficient of determination, matching of a maximum wavelength value.

[0110] Fluorescence leak detection materials for hydraulic and refrigerant systems are already commercially available. It is also possible to monitor gaseous systems with natural gas, propane, ammonia, etc. as operating medium. In this case, suitable fluorophores for the respective gases have to be added.

LIST OF REFERENCE SIGNS

[0111] 100 device [0112] 101 light source [0113] 102 sensor [0114] 103 data processing unit, database [0115] 104 data storage unit [0116] 105 fluid [0117] 106 dye [0118] 110 system (stove) [0119] 111 scene (cone)