Spectral stereo vision device for inspection inside high-temperature narrow cavities

Abstract

A spectroscopic stereo vision device for detecting objects within a high-temperature, narrow cavity comprises: a color spectroscopic imaging module, disposed outside the high-temperature, narrow cavity, for imaging the object; and a high-temperature optical lens barrel, disposed within the high-temperature, narrow cavity. The high-temperature optical lens barrel is provided with a semi-transparent mirror, a reflector, a red spectrum filter, and a blue spectrum filter. Light from the object's real image is reflected by the reflector, filtered by the red spectrum filter, and then passes through the semi-transparent mirror before entering the color spectroscopic imaging module for imaging. Light reflected from the object is filtered by the blue spectrum filter and then reflected by the reflector before entering the color spectroscopic imaging module for imaging. By providing a dual reflector and a color spectroscopic device within the high-temperature optical lens barrel, a compact optical path with a strong ability to withstand high temperatures is formed, meeting the requirements for detecting objects within a high-temperature, narrow cavity. Light paths with different viewing angles can be output and provided to cameras outside the high-temperature cavity.

Description

Technical Field

[0001] The present invention relates to the fields of computer vision and monitoring, and in particular to a spectroscopic stereoscopic vision device for detecting the interior of a high-temperature narrow cavity. Background Art

[0002] Online measurement of displacement and strain of mechanical components in high-temperature environments is a widespread but challenging task. This is particularly true in confined environments like aircraft turbine engines, where space for testing equipment is limited and ambient temperatures can range from 500 to 1200 degrees Celsius, creating harsh operating conditions. Measuring the strain field of blades rotating at high speeds has long been a key challenge for the industry.

[0003] Conventional stereo digital image correlation (DIC) or other computer-based binocular stereo vision applications require two similar cameras to observe the object at a fixed stereoscopic perspective. This requires a hardware synchronizer to coordinate the simultaneous exposures of the two cameras and a dedicated support bracket to secure the cameras. However, these are bulky and unsuitable for inspection inside the ultra-high-temperature, narrow cavities described above.

[0004] Conventional single-camera binocular detection methods often use a split-screen binocular observation device to image part of the camera's target surface. Its viewing angle is relatively limited and it is difficult to meet the limitations of measurement environment parameters. Summary of the Invention

[0005] In view of this, the main purpose of the present invention is to provide a spectroscopic stereoscopic vision device for detecting the interior of a high-temperature narrow cavity, in order to partially solve at least one of the above-mentioned technical problems.

[0006] In order to achieve the above object, the present invention provides a spectroscopic stereoscopic vision device, comprising:

[0007] A color spectroscopic imaging module is provided outside the high-temperature narrow cavity and is used for imaging an object;

[0008] A high-temperature optical lens barrel is arranged inside a high-temperature narrow cavity. A semi-transparent reflector, a reflector, a red spectrum filter, and a blue spectrum filter are arranged inside the high-temperature optical lens barrel. Light of the real image of the object is reflected by the reflector, filtered by the red spectrum filter, passes through the semi-transparent reflector, and enters the color spectroscopic imaging module for imaging; light reflected by the object is filtered by the blue spectrum filter, and then reflected by the reflector and enters the color spectroscopic imaging module for imaging.

[0009] The color spectroscopic imaging module is a CFA Byer array color camera, a 3CCD / CMOS color camera or a discrete color spectroscopic camera.

[0010] The CFA Byer array color camera is a camera in which a single pixel is sensitive only to a specific spectrum of light. Color filters corresponding to the pixels are installed on the CCD / CMOS array, so that specific pixels can only be sensitive to specific colors of light.

[0011] The 3CCD / CMOS color camera is a camera mechanism that integrates three sensors with color filters and a spectrometer group; it can reconstruct blue, green or red photosensitive images by reading the sensor data under the three color filters respectively.

[0012] Wherein, the outer diameter of the high-temperature optical lens barrel is 1 cm to 2 cm.

[0013] Based on the above technical solution, it can be seen that the spectroscopic stereoscopic vision device of the present invention has at least one of the following beneficial effects compared with the prior art:

[0014] 1. The present invention proposes a spectroscopic stereo vision device for detecting the interior of a high-temperature narrow cavity. By arranging a double reflector and a color spectroscopic device within a high-temperature optical tube lens, a light path with a small size and strong ability to withstand high temperatures is formed, which meets the requirements of detecting the interior of a high-temperature narrow cavity and can output light paths with different perspectives to provide to a camera outside the high-temperature cavity.

[0015] 2. The single camera in the device of the present invention is a color camera, which can obtain binocular images and has a wide viewing angle of the entire target surface, realizing the measurement of three-dimensional digital image-related morphology, displacement and deformation of high-temperature interiors with a small device. The color camera can be a single-target color camera or a 3CCD based on a color spectroscopic optical path or a dual high-speed camera, meeting the requirements of high-precision measurement and high-speed measurement at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 2 is a schematic structural diagram of a spectroscopic stereo vision device for performing single-camera testing according to an embodiment of the present invention;

[0017] Figure 2 Schematic diagram of the imaging principle of the CFA Byer array color camera of the present invention;

[0018] Figure 3 This is a diagram of the imaging principle of the 3CCD / CMOS color camera of the present invention;

[0019] Figure 4 2. It is a schematic diagram of the two-dimensional structure of a spectroscopic stereo vision device for dual-camera testing according to an embodiment of the present invention;

[0020] Figure 5 It is a three-dimensional side view schematic diagram of an embodiment of the present invention applied to the interior of an aircraft engine.

[0021] In the above drawings, the meanings of the reference numerals are as follows:

[0022] 1. Color spectroscopic imaging module; 2. High-temperature optical lens barrel; 3. Semi-transparent reflector;

[0023] 4. Reflector; 5. Red spectrum filter; 6. Blue spectrum filter;

[0024] 7. High-temperature container interface; 8. Virtual camera No. 1; 9. Virtual camera No. 2;

[0025] D, object to be measured; L1, optical center line of virtual image No. 1; L2, optical center line of virtual image No. 2. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0027] Figure 1 Schematic diagram of the structure of the spectroscopic stereo vision device for single-camera testing of the present invention; Figure 1 As shown, the spectroscopic stereoscopic vision device includes:

[0028] The color spectroscopic imaging module 1 is arranged outside the high-temperature narrow cavity and is used for imaging objects. The color spectroscopic imaging module can be a conventional CFA Byer array color camera, a 3CCD / CMOS camera and a discrete color spectroscopic camera.

[0029] Dual-view imaging principle of CFA Byer array color camera and color spectroscopic camera:

[0030] A CFA Byer array color camera is a camera in which a single pixel is sensitive only to a specific spectrum of light. Figure 2 As shown in the figure, the CCD / CMOS sensor is equipped with color filters corresponding to the pixels, so that specific pixels can only be sensitive to specific colors of light. By reading the patterns under different color filters, it can reconstruct the blue, green or red light-sensitive images.

[0031] 3CCD / CMOS color camera is a camera structure that integrates three sensors with color filters and a spectrometer group. Figure 3 As shown, by reading the sensor data under the three color filters respectively, the blue, green or red photosensitive images can be reconstructed.

[0032] A high-temperature optical lens barrel 2 is provided inside a high-temperature narrow cavity. A semi-transparent reflector 3, a reflector 4, a red spectrum filter 5, and a blue spectrum filter 6 are provided inside the high-temperature optical lens barrel. The light of the real image of the object is reflected by the reflector 4, filtered by the red spectrum filter 5, passes through the semi-transparent reflector 3, and enters the color spectroscopic imaging module 1 for imaging; the light reflected by the object is filtered by the blue spectrum filter 6, and then reflected by the reflector 4 and enters the color spectroscopic imaging module for imaging.

[0033] Based on the dimensions of the semi-transparent reflector 3, reflector 4, red spectrum filter 5, and blue spectrum filter 6, the outer diameter of the high-temperature optical lens barrel 2 can be set to 1 cm to 2 cm, and the optical path volume is small. In other words, the visual device can meet the requirement of a workpiece opening of 1 cm to 2 cm.

[0034] The principle of the spectroscopic stereo vision device to detect objects inside a high-temperature narrow cavity is as follows:

[0035] A diffusely reflected light from the object D to be tested inside a high-temperature narrow cavity enters the cavity, is reflected by the reflector 4, filtered into red light by the red spectrum filter 5, and then transmitted through the semi-transparent reflector 3 to enter the color spectroscopic imaging module 1. Another diffusely reflected light from the object D to be tested is filtered into blue light by the blue spectrum filter 6, and then reflected by the semi-transparent reflector 3 to enter the color spectroscopic imaging module 1. Since the spectra of the red spectrum filter 5 and the blue spectrum filter 6 do not overlap, the two diffusely reflected lights are captured and imaged by the red and blue pixels in the color spectroscopic imaging module 1 that are sensitive to red and blue respectively. The red and blue pixels are extracted later to obtain the first and second images with different perspectives. Virtual images of the color spectroscopic imaging module 1 are made along the semi-transparent reflector 3 and the reflector 4, respectively, to obtain the following: Figure 1 , virtual camera No. 1 8 and virtual camera No. 2 9 are shown. The first and second images are equivalent to the surface of the object D observed by virtual camera No. 1 8 and virtual camera No. 2 9 along the optical center line L1 and the optical center line L2 of the virtual image, respectively. The first and second images obtained from different perspectives by the cameras can be used to obtain the topography, displacement, and deformation information of the surface of the object D using a digital image correlation algorithm.

[0036] Example 1

[0037] The high-temperature optical lens barrel in the system is embedded in the high-temperature container interface 7. Inside the high-temperature container is an object D to be measured. The color spectroscopic imaging part 1 is arranged outside the high-temperature narrow cavity; the high-temperature optical lens barrel 2 is arranged inside the high-temperature narrow cavity. The high-temperature optical lens barrel 2 is provided with a semi-transparent reflector 3, a reflector 4, a red spectrum filter 5, and a blue spectrum filter 6. The light of the real image of the object is reflected by the reflector 4, filtered by the red spectrum filter 5, and then passes through the semi-transparent reflector 3 to enter the color camera 1 for imaging; the light reflected by the object is filtered by the blue spectrum filter 6, and then reflected by the reflector 3 to enter the color camera 1 for imaging. The first and second images of different perspectives obtained by the camera can obtain the morphology, displacement, and deformation information of the surface of the object to be measured through the digital image correlation algorithm.

[0038] This embodiment is a single-camera test, and its structure is as follows Figure 1 shown.

[0039] Example 2

[0040] The difference between this embodiment and embodiment 1 is that a set of color cameras, semi-transparent reflectors, red spectrum filters and blue spectrum filters are added above the high temperature container interface to form a dual-camera spectroscopic stereo device. The structural diagram is shown in FIG. Figure 4 shown.

[0041] The above-mentioned spectroscopic stereo vision device can be used to detect objects such as the interior of an aircraft engine, and its application to the three-dimensional side view schematic diagram of the interior of an aircraft engine is as follows: Figure 5 shown.

[0042] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A spectroscopic stereoscopic vision device, characterized in that: Used for object detection inside high-temperature narrow cavities, including: A color spectroscopic imaging module, which is a CFA Byer array color camera, a 3CCD / CMOS color camera, or a discrete color spectroscopic camera, is disposed outside the high-temperature narrow cavity and is used for imaging objects; The high-temperature optical lens barrel has an outer diameter of 1 cm to 2 cm and is arranged inside a high-temperature narrow cavity. The high-temperature optical lens barrel is provided with a semi-transparent reflector, a reflector, a red spectrum filter and a blue spectrum filter. The red spectrum filter and the blue spectrum filter are arranged perpendicular to each other, and the semi-transparent reflector is arranged at an angle of 45 degrees to the blue spectrum filter. The interior of the high-temperature narrow cavity is separated from the exterior of the high-temperature narrow cavity by a high-temperature container interface. An object to be measured is arranged inside the high-temperature narrow cavity. A diffusely reflected light of the object to be measured is reflected by the reflector and then filtered by the red spectrum filter. The red light is then transmitted through a semi-transparent mirror and enters the color spectroscopic imaging module, while the other diffusely reflected light from the object to be measured is filtered into blue light by a blue spectrum filter, then reflected by a semi-transparent mirror and enters the color spectroscopic imaging module. The spectra of the red spectrum filter and the blue spectrum filter do not overlap, so the two diffusely reflected light rays are captured and imaged by the red and blue pixels in the color spectroscopic imaging module that are sensitive to red and blue respectively. Among them, a group of color cameras, semi-transparent mirrors, red spectrum filters and blue spectrum filters are added above the interface of the high-temperature container to form a dual-camera spectroscopic stereo device.

2. The spectroscopic stereoscopic device according to claim 1, wherein: A CFA Byer array color camera is a camera in which individual pixels are sensitive only to a specific spectrum of light. Color filters corresponding to the pixels are installed on the CCD / CMOS array, allowing specific pixels to be sensitive only to specific colors of light.

3. The spectroscopic stereoscopic device according to claim 1, wherein: The 3CCD / CMOS color camera is a camera mechanism that integrates three sensors with color filters and a spectrometer group; it can reconstruct blue, green or red photosensitive images by reading the sensor data under the three color filters respectively.

4. The spectroscopic stereoscopic device according to claim 1, wherein: Virtual images of the color spectroscopic imaging module are taken along the semi-transparent reflector and the reflector, respectively, to obtain virtual cameras No. 1 and No.

2. The first image and the second image are respectively equal to the surface of the object to be measured observed by the virtual cameras No. 1 and No. 2 along the optical center line of the virtual image No. 1 and the optical center line of the virtual image No.

2. Through the first image and the second image obtained from different perspectives by the camera, the morphology, displacement and deformation information of the surface of the object to be measured can be obtained by using a digital image correlation algorithm.

Images