阅读说明：本技术 一种耐辐照的水下变形视觉测量单元及测量方法 (Irradiation-resistant underwater deformation vision measurement unit and measurement method ) 是由 陈晓波 王玉坤 张洪辉 习俊通 洪子橙 胡国栋 于 2021-08-12 设计创作，主要内容包括：本发明提供一种耐辐照的水下变形视觉测量单元及测量方法,包括：图像采集模块和激光模块,外侧通过钨合金屏蔽层进行核辐射屏蔽；图像采集模块和激光模块的数据线集成后通过水密接插件与外部控制器相连；用于保证测量单元有效工作距离的反射部件；用于安装图像采集模块和激光模块的底座；与底座配合连接形成密封空间的外壳,图像采集模块、激光模块以及反射部件位于该密封空间中,其中两个反射部件位于该密封空间的两端部附近,图像采集模块和激光模块位于两个反射部件之间。本发明不仅具备抗辐照性能,还具备深水防水效果,通过卡箍连接块安装到不锈钢连接管,集成多组视觉测量单元,可进行燃料组件深水、辐照环境下的瞬态非接触式变形测量。(The invention provides an irradiation-resistant underwater deformation vision measurement unit and a measurement method, wherein the irradiation-resistant underwater deformation vision measurement unit comprises: the outer sides of the image acquisition module and the laser module are shielded from nuclear radiation through a tungsten alloy shielding layer; the data lines of the image acquisition module and the laser module are integrated and then are connected with an external controller through a watertight connector; a reflection member for securing an effective working distance of the measurement unit; a base for mounting the image acquisition module and the laser module; and the image acquisition module, the laser module and the reflection parts are positioned in the sealed space, wherein the two reflection parts are positioned near two end parts of the sealed space, and the image acquisition module and the laser module are positioned between the two reflection parts. The invention not only has the anti-irradiation performance, but also has the deepwater waterproof effect, is arranged on the stainless steel connecting pipe through the hoop connecting block, integrates a plurality of groups of vision measuring units, and can carry out transient non-contact deformation measurement on the fuel assembly in deepwater and irradiation environments.)

1. An irradiation resistant underwater distortion vision measurement unit comprising:

the laser module emits two laser stripes, and nuclear radiation shielding is carried out on the outer side of the laser module through a tungsten alloy shielding layer;

the image acquisition module is used for acquiring a calibration plate image and a laser stripe image of the laser module, carrying out camera calibration and light plane calibration, and carrying out nuclear radiation shielding on the outer side of the image acquisition module through a tungsten alloy shielding layer; the data lines of the image acquisition module and the laser module are integrated and then connected with an external controller through a watertight connector;

a reflection part for reflecting the laser stripe of the laser module and the camera view field of the image acquisition module, thereby ensuring an effective working distance of the measurement unit;

the base is used for installing and fixing the image acquisition module, the laser module and the reflecting component;

the shell, with the base cooperation is connected and is formed sealed space, image acquisition module, laser module and reflection part are located this sealed space, and wherein two reflection part is located near this sealed space's both ends, image acquisition module with the laser module is located two between the reflection part.

2. The radiation-resistant underwater vision measurement unit of claim 1, wherein the angle between the reflection component near the image acquisition module and the base is 75 °, and the angle between the reflection component near the laser module and the base is 45 °.

3. The irradiation resistant underwater deformation vision measuring unit of claim 1, wherein the image acquisition module employs an industrial camera, the industrial camera is mounted with a lens and a filter, the industrial camera is mounted on a camera support frame; the industrial camera, the lens and the optical filter form a whole after being installed, a tungsten alloy shielding layer is arranged on the periphery of the whole, and the whole is wrapped in the tungsten alloy shielding layer and used for shielding nuclear radiation.

4. The irradiation-resistant underwater deformation vision measuring unit of claim 3, wherein the laser module comprises two lasers, the lasers are mounted on a laser fixing block, the laser fixing block is fixed on a laser supporting frame, the lasers and the laser fixing block are mounted to form a whole, a tungsten alloy shielding layer is arranged on the periphery of the whole to wrap the whole inside for shielding nuclear radiation; one said industrial camera and two said lasers form a double knife line laser triangulation.

5. The irradiation-resistant underwater deformation vision measuring unit according to claim 4, wherein the reflecting component is a silver-plated reflecting mirror, the two silver-plated reflecting mirrors are respectively fixed on the camera support frame and the laser support frame, an included angle between the camera support frame and the base is 75 degrees, and an included angle between the laser support frame and the base is 45 degrees, so as to ensure effective working distances of the industrial camera and the laser.

6. The irradiation tolerant underwater vision measurement unit of any one of claims 1-5, further comprising: and the sealing component is positioned between the base and the shell and used for ensuring the sealing connection of the base and the shell.

7. The irradiation tolerant underwater vision measurement unit of any one of claims 1-5, further comprising: and the lead glass is embedded in the shell of the vision measuring unit and is compressed through a lead glass fixing frame.

8. A method for measuring a grid or a base of a fuel assembly, which is implemented by using the radiation-resistant underwater deformation visual measuring unit of any one of claims 1 to 7, and comprises the following steps:

laser modules of the multiple groups of visual measurement units emit laser stripes at the same time, and the laser stripes are reflected by the reflecting part and then projected to a fuel assembly framework or a base;

the image acquisition modules of the multiple groups of vision measurement units are simultaneously reflected by the reflecting component to capture and obtain laser stripe images;

carrying out image segmentation and optical center extraction on the captured laser stripe image to obtain an upper laser stripe center and a lower laser stripe center;

and performing three-dimensional reconstruction based on the underwater multi-medium refraction model and the upper and lower light plane equations to obtain three-dimensional point cloud data of the fuel assembly grillwork or the base, and calculating subsequent bending deformation to realize measurement of the fuel assembly grillwork or the base.

9. The radiation-resistant underwater deformation vision measuring method of claim 8, wherein the vision measuring units are mounted to the stainless steel connecting pipe through a hoop connecting block, and a plurality of sets of vision measuring units are integrated to measure the fuel assembly grids or bases within an underwater working distance range.

10. The irradiation resistant underwater deformation vision measuring method of claim 8, wherein the laser modules of the multiple groups of vision measuring units emit laser stripes simultaneously, and after being reflected by the reflecting component, the laser stripes penetrate through the lead glass and are projected to the fuel assembly grids or bases.

The image acquisition modules of the multiple groups of vision measurement units are simultaneously reflected by the reflecting component and penetrate through the lead glass to capture and obtain laser stripe images.

Technical Field

The invention relates to the field of nuclear power station fuel assembly deformation measurement, in particular to a non-contact vision measurement unit and a measurement method based on a double-knife-line laser triangulation principle.

Background

The fuel assembly consists of a control rod, an upper tube seat, an upper grid, a guide tube, a fuel rod, a middle grid, a lower tube seat and other assemblies, is a core component for generating energy by a nuclear energy system, works in high-temperature, high-pressure and high-radiation circulating water for a long time, is easily subjected to bending deformation, torsional deformation and the like under the influence of a plurality of factors such as assembly stress, thermal stress and the like, and can influence the normal insertion of the fuel rod when the deformation is serious so as to endanger the safe operation of a reactor.

In order to ensure the safety in the nuclear energy development process, the nuclear power plant needs to periodically perform maintenance operation on fuel assemblies and other components in a reactor core, and whether the deformation is within a safety range is evaluated through a detection result, so that a worker is reminded to replace the fuel assemblies in time. Since the fuel assembly works in a radiation environment for a long time, the adoption of a contact measurement mode for the fuel assembly is greatly limited, and a non-contact detection technology for the fuel assembly is urgently needed.

In foreign countries, the visual measurement unit developed and designed by Mabema corporation in sweden based on the principle of single-knife-line laser triangulation mainly comprises an industrial camera, a lens, a laser, a shell and the like. The measuring system adopts the modularized design concept, 8 groups of vision measuring units are installed on the pipeline to be aligned, after the fuel assembly and the measuring system are hung, the system measures the fuel assembly within 3 seconds approximately, then the system rotates for three times by 90 degrees, the total time for completing the measurement of four sides of the fuel assembly is about 40 seconds, the overall precision is better than 0.5mm, but the measuring unit has lower measuring precision, and the measuring efficiency is to be improved.

In China, a binocular radiation-resistant camera module designed by institute of optoelectronic technology of Chinese academy of sciences mainly comprises four parts, namely a radiation-resistant lens, a sensor, a control transmission unit and a mechanical main body, all parts are sealed through an aluminum alloy shell, and the deformation state of a fuel assembly is calculated based on image domain algorithm processing.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide an irradiation-resistant underwater deformation vision measurement unit and a measurement method, which have certain irradiation resistance and deep water-proof effect, can perform transient non-contact deformation measurement under a deep water and irradiation environment of a fuel assembly, help a nuclear power station to regularly perform maintenance operation on the fuel assembly and other components in a reactor core, and assist in screening and judging the safety risk degree of the fuel assembly.

In a first aspect of the invention, there is provided an irradiation-resistant underwater deformation vision measuring unit comprising:

the laser module emits two laser stripes, and nuclear radiation shielding is carried out on the outer side of the laser module through a tungsten alloy shielding layer;

the image acquisition module is used for acquiring a calibration plate image and a laser stripe image of the laser module, carrying out camera calibration and light plane calibration, and carrying out nuclear radiation shielding on the outer side of the image acquisition module through a tungsten alloy shielding layer; the data lines of the image acquisition module and the laser module are integrated and then connected with an external controller through a watertight connector;

a reflection part for reflecting the laser stripe of the laser module and the camera view field of the image acquisition module, thereby ensuring an effective working distance of the measurement unit;

the base is used for installing and fixing the image acquisition module, the laser module and the reflecting component;

the shell, with the base cooperation is connected and is formed sealed space, image acquisition module, laser module and reflection part are located this sealed space, and wherein two reflection part is located near this sealed space's both ends, image acquisition module with the laser module is located two between the reflection part.

Preferably, an included angle between the reflection component near the image acquisition module and the base is 75 degrees, and an included angle between the reflection component near the laser module and the base is 45 degrees.

Preferably, the image acquisition module adopts an industrial camera, a lens and an optical filter are mounted on the industrial camera, and the industrial camera is mounted on a camera support frame; and nuclear radiation shielding is carried out on the outer sides of the industrial camera, the lens and the optical filter through a tungsten alloy shielding layer.

Preferably, the laser module comprises two lasers, the lasers are mounted on a laser fixing block, the laser fixing block is fixed on a laser supporting frame, and the outsides of the lasers and the laser fixing block are shielded from nuclear radiation through a tungsten alloy shielding layer; one said industrial camera and two said lasers form a double knife line laser triangulation.

Preferably, the reflecting component adopts silver-plated reflecting mirrors, the two silver-plated reflecting mirrors are respectively fixed on the camera support frame and the laser support frame, an included angle between the camera support frame and the base is 75 degrees, and an included angle between the laser support frame and the base is 45 degrees, so that the effective working distance of the industrial camera and the laser can be ensured.

Preferably, the irradiation-resistant underwater deformation vision measuring unit further comprises: and the sealing component is positioned between the base and the shell and used for ensuring the sealing connection of the base and the shell.

Preferably, the irradiation-resistant underwater deformation vision measuring unit further comprises: and the lead glass is embedded in the shell of the vision measuring unit and is compressed through a lead glass fixing frame.

In a second aspect of the present invention, there is provided a method for measuring a grid or a base of a fuel assembly, which is implemented by using the above irradiation-resistant underwater deformation vision measuring unit, and includes:

laser modules of the multiple groups of visual measurement units emit laser stripes at the same time, and the laser stripes are reflected by the reflecting part and then projected to a fuel assembly framework or a base;

the image acquisition modules of the multiple groups of vision measurement units are simultaneously reflected by the reflecting component to capture and obtain laser stripe images;

carrying out image segmentation and optical center extraction on the captured laser stripe image to obtain an upper laser stripe center and a lower laser stripe center;

and performing three-dimensional reconstruction based on the underwater multi-medium refraction model and the upper and lower light plane equations to obtain three-dimensional point cloud data of the fuel assembly grillwork or the base, and calculating subsequent bending deformation to realize measurement of the fuel assembly grillwork or the base.

Compared with the prior art, the embodiment of the invention has at least one of the following beneficial effects:

according to the measuring unit and the measuring method provided by the invention, the reflection component, the two lasers and the industrial camera are matched, and the long measuring distance, the high measuring precision and the high measuring speed can be realized by benefiting from the reflection type structural design and installation and the double-knife-line laser triangulation principle.

The measuring unit and the measuring method provided by the invention have certain radiation resistance and deep water-proof effect, and can be used for transient non-contact deformation measurement of the fuel assembly in deep water and radiation environments.

The measuring unit and the measuring method provided by the invention can help the nuclear power station to regularly overhaul the fuel assemblies and other components in the reactor core, and assist in screening and judging the safety risk degree of the fuel assemblies.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic diagram of an underwater deformation vision measuring unit in a preferred embodiment of the present invention;

FIG. 2 is a schematic illustration of a tungsten alloy shield layer of an underwater deformation vision measurement unit in a preferred embodiment of the present invention;

FIG. 3 is a front view of the underwater deformation vision measuring unit in a preferred embodiment of the present invention;

FIG. 4 is a top view of the underwater deformation vision measuring unit in a preferred embodiment of the present invention;

in the figure: 11 is an industrial camera, 12 is a lens, 13 is a light filter, 14 is a camera support frame, 21 is a laser, 22 is a laser fixing block, 23 is a laser support frame, 31 is a base, 32 is a mechanical sealing ring, 4 is a watertight connector, 5 is a reflector, 61 is a shell, 62 is lead glass, 63 is a lead glass fixing frame, and 7 is a tungsten alloy shielding layer.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

As shown in fig. 1 to 4, an irradiation-resistant underwater deformation vision measuring unit according to an embodiment of the present invention specifically includes: image acquisition module, laser module, reflection part, base and shell, wherein: the laser module emits two laser stripes, and nuclear radiation shielding is carried out on the outer side of the laser module through a tungsten alloy shielding layer 7; the image acquisition module acquires a calibration plate image and a laser stripe image emitted by the laser module, the calibration plate image and the laser stripe image are transmitted to a computer through a data line to perform camera calibration and light plane calibration, and nuclear radiation shielding is performed on the outer side of the image acquisition module through a tungsten alloy shielding layer 7; the data lines of the image acquisition module and the laser module are integrated and then are connected with an external controller through a watertight connector 4; the reflecting component reflects the laser stripes of the laser module and the camera view field of the image acquisition module, so that the effective working distance of the measuring unit is ensured; preferably, the included angle between the reflection component near the image acquisition module and the base 31 is 75 degrees, and the included angle between the reflection component near the laser module and the base 31 is 45 degrees; the base 31 is used for installing and fixing the image acquisition module, the laser module and the reflection component; the housing 61 is coupled to the base 31 to form a sealed space in which the image capture module, the laser module, and the reflective member are located, wherein the two reflective members are located near both ends of the sealed space, and the image capture module and the laser module are located between the two reflective members.

According to the vision measuring unit of the embodiment of the invention, the measuring unit adopts a double-knife-line laser triangulation principle, 1 industrial camera 11 and 2 lasers 21 are integrated inside, and the vision measuring unit has certain radiation resistance and deep water-proof effect and can be used for transient non-contact deformation measurement in deep water and radiation environments of fuel assemblies.

In the embodiment, the image acquisition module adopts an industrial camera 11, a lens 12 and an optical filter 13 are mounted on the industrial camera 11, and the industrial camera 11 is mounted on a camera support frame 14; the industrial camera 11, the lens 12, and the optical filter 13 are mounted to form a unit, and the tungsten alloy shielding layer 7 is provided around the unit to cover the unit therein for nuclear radiation shielding.

Referring to fig. 1 and 2, in the present embodiment, the laser module includes two lasers 21, the two lasers 21 are mounted on a laser fixing block 22, the laser fixing block 22 is fixed on a laser supporting frame 23, the lasers 21 and the laser fixing block 22 are mounted to form a whole, a tungsten alloy shielding layer 7 is disposed on the periphery of the whole, and the whole is wrapped therein for nuclear radiation shielding; one industrial camera 11 and two lasers 21 constitute a double knife-line laser triangulation. In a specific embodiment, after the lens 12 and the optical filter 13 are installed on the industrial camera 11, the industrial camera is fixed on the camera support frame 14 through screw connection, and nuclear radiation shielding is performed on the outer side of the industrial camera through the customized tungsten alloy shielding layer 7; the 2 lasers 21 are installed on a laser fixing block 22 through screw connection, the laser fixing block 22 is fixed on a laser supporting frame 23 through screw connection, and nuclear radiation shielding is carried out on the outer side of the laser fixing block through a tungsten alloy shielding layer 7; the data lines of the industrial camera 11 and the laser 21 are integrated and then connected with an external controller through a watertight connector 4. Further, the camera support frame 14 and the laser support frame 23 are fixed on the base 31, and the reflection component adopts two silver-plated reflectors 5, 2 silver-plated reflectors 5 respectively fixed on the camera support frame 14 and the laser support frame 23.

Referring to fig. 3 and 4, in a preferred embodiment, the vision measuring unit further includes: lead glass 62 and lead glass mount 63, 2 lead glass 62 inlay in vision measuring unit shell 61 to compress tightly through lead glass mount 63, when guaranteeing that industrial camera, laser instrument are sealed light-permeable, possess the radiation resistance performance of certain degree.

In order to better achieve the sealing effect, in an embodiment, the base 31 is chamfered, the mechanical seal ring 32 is placed in the groove, physical sealing is performed through the mechanical seal ring 32, and the base 31 and the shell 61 are fastened through screw connection, so that the sealing effect is ensured. Specifically, the housing 61 and the base 31 are made of corrosion-resistant stainless steel processed by an electrolytic polishing process, so that the retention of pollutants can be effectively reduced.

In some embodiments, the industrial camera 11 is a Basler acA1920-48gm area-array camera model, with a resolution of 230 ten thousand pixels, a pixel size of 4.8 μ M and a frame rate of 50fps, and the lens 12 is a Ricoh FL-CC1614-2M zoom lens model, with a focal length of 16 mm. The laser 21 used a 650nm red laser with a wavelength of 150mW power. Of course, in other embodiments, other types of industrial cameras, lasers, etc. may be used.

In some embodiments, 2 pieces of lead glass 62 having a thickness of 5mm are embedded in the housing 61 of the vision measuring unit and pressed by a lead glass holder 63. Of course, in other embodiments, lead glass of other thicknesses may be used.

In some embodiments, 2 silver-plated mirrors 5 with a thickness of 2mm are respectively fixed on the camera support frame 14 and the laser support frame 23 to emit laser stripes emitted by the laser 21, so as to ensure the working view field of the industrial camera 11. Of course, in other embodiments, other thicknesses of the silvered mirrors may be used.

The underwater working distance of the vision measuring unit in the embodiment of the invention can be 900 +/-100 mm, the measuring distance is long, the measuring precision is high, and the measuring speed is high.

In the embodiment of the invention, the industrial camera 11 and the laser 21 are isolated by the tungsten alloy shielding layer 7, the industrial camera 11 and the laser 21 are installed by a reflection type structural design, the laser 21 emits laser stripes, the laser stripes are reflected by the reflector 5 and then projected to the calibration plate through the lead glass 62, and the post industrial camera 11 is reflected by the reflector 5 and then captured and obtained laser stripe images through the lead glass 62 for subsequent computer processing. The visual measurement unit can ensure the working view field of the electronic component and reduce the loss of nuclear radiation to the electronic component.

In the embodiment of the invention, the mechanical seal ring 32 is used for physical sealing, the deep waterproof watertight connector 4 is used for connecting an external controller, and the vision measuring unit can meet the deepwater waterproof effect for a certain time.

In another embodiment, the present invention uses the visual measuring unit of the above embodiments to measure the fuel assembly grid or the base. When the device is used before measurement, the vision measuring units are installed on the stainless steel connecting pipe through the hoop connecting blocks, a plurality of groups of vision measuring units are integrated, and the fuel assembly grillwork or the base is measured within the underwater working distance range. The specific number of visual measurement cell groups is determined based on the specific size, number and measurement requirements of the actual measured fuel assembly grids or bases.

During measurement, the lasers 21 of the multiple groups of vision measuring units simultaneously emit laser stripes, and the laser stripes are reflected by the reflecting mirror 5, penetrate through the lead glass 62 and are projected to the grids or the bases of the fuel assemblies. Then, the industrial cameras 11 of the multiple groups of vision measuring units are reflected by the reflecting mirror 5 at the same time, and the laser stripe images are captured and obtained through the lead glass 62. And then, carrying out image segmentation and optical center extraction on the captured laser stripe image to obtain the upper and lower laser stripe centers. And finally, performing three-dimensional reconstruction based on the underwater multi-medium refraction model and the upper and lower light plane equations to obtain three-dimensional point cloud data of the fuel assembly grillwork or the base for subsequent bending deformation calculation to realize final measurement.

The embodiment of the invention not only has certain radiation resistance, but also has certain deepwater waterproof effect, and the transient non-contact deformation measurement of the fuel assembly in deepwater and irradiation environments can be carried out by installing the hoop connecting block on the stainless steel connecting pipe and integrating a plurality of groups of visual measurement units.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The above-described preferred features may be used in any combination without conflict with each other.