Rapid fusion device for multi-view panoramic measurement on complex test site

Abstract

The utility model discloses a rapid fusion device for multi-view panoramic measurement on a complex test site. The rapid fusion device is a long-strip-shaped calibration block with a polyhedral cross section. A plurality of circumferential surfaces of the calibration block are reference surfaces, and coordinate system grooves with given depth and width are processed on the reference surfaces; the end face of the calibration block is a reference face, and a standard threaded hole is machined in the center of the reference face. And speckles suitable for tests are manufactured on the surfaces of the reference surface and the reference surface. According to the utility model, a multi-view fusion device is simplified into a precision machining reference device, so that measurement images of a plurality of views can be fused together simply and conveniently, and then a high-precision measurement wind tunnel test of multi-view morphology and deformation can be realized quickly.

Description

Technical Field

[0001] The utility model relates to the technical field of wind tunnel tests, in particular to a fast fusion device for multi-viewing angle panoramic measurement at a complex test site. Background Art

[0002] Model morphology and deformation measurement in modern wind tunnel tests has gradually become a common measurement technology in wind tunnel tests. As a non-contact, high-precision measurement method, visual measurement technology has been increasingly applied to model morphology and deformation measurement. The requirements for model morphology and deformation measurement in modern wind tunnel tests are getting higher and higher. The test model is no longer a single rotational body, but a model with many asymmetric and complex configurations; therefore, when measuring the morphology or deformation of the model, it is necessary to record and process the entire model rather than just one side.

[0003] At present, the method of multi-view fusion that is widely used in industry is to use conventional plane targets to calibrate dual cameras of a single view and establish their respective coordinate systems; then measure the common large-scale reference target and perform coordinate transformation to achieve the unification of the full-field coordinates. The principle of this method is simple, but the process is complicated and the operation is cumbersome. In addition, the asynchronicity of the measurement and the accuracy of the large-scale reference target will cause large errors; resulting in low measurement accuracy and almost impossible to apply to wind tunnel tests. This method generally requires that the field of view of camera pairs with different viewpoints needs to have a certain overlap area, and there must be a corresponding number of feature points or feature areas in the overlap area; otherwise, it is impossible to merge the images of the two viewpoints with high precision. This merging process generally requires manual intervention and is time-consuming and labor-intensive, with low accuracy, and cannot achieve automatic recognition and processing by the program. Utility Model Content

[0004] The utility model solves the problem by overcoming the shortcomings of the prior art and providing a rapid fusion device for multi-perspective panoramic measurement at complex test sites, which simplifies the multi-perspective fusion device into a precision-machined reference device, and can simply and conveniently fuse measurement images of multiple perspectives together, thereby quickly realizing high-precision measurement of multi-perspective morphology and deformation in wind tunnel tests.

[0005] In order to solve the above technical problems, the utility model discloses a rapid fusion device for multi-view panoramic measurement of complex test sites, the rapid fusion device is a long strip calibration block with a polyhedron cross section;

[0006] Multiple circumferential surfaces of the calibration block are reference surfaces, and coordinate system grooves with given depth and width are processed on the reference surfaces;

[0007] The end face of the calibration block is the reference surface, and a standard threaded hole is machined at the center of the reference surface;

[0008] The surfaces of the reference surface and the datum surface are made with speckles suitable for the test.

[0009] In the above-mentioned rapid fusion device for multi-view panoramic measurement of complex test sites, the reference coordinates of each reference surface are directly processed into coordinate system grooves on the surface.

[0010] In the above-mentioned rapid fusion device for multi-view panoramic measurement at a complex test site, the size ratio of the rapid fusion device to the test specimen is 1:1.

[0011] In the above-mentioned fast fusion device for multi-view panoramic measurement of complex test sites, the test requires that: the field of view of the camera at a certain view angle needs to fully cover at least one reference surface of the fast fusion device.

[0012] In the above-mentioned fast fusion device for multi-view panoramic measurement of complex test sites, the size of the speckle corresponds to 3 to 5 pixels in the image, and the shape of the speckle is obtained randomly.

[0013] In the above-mentioned fast fusion device for multi-view panoramic measurement of complex test sites, the width and depth of the coordinate system groove both correspond to 1 to 2 pixels in the image.

[0014] In the above-mentioned rapid fusion device for multi-view panoramic measurement of complex test sites, during the test, the coordinate transformation relationship corresponding to the corresponding reference surface of the rapid fusion device is used to transform the coordinates of the images of multiple viewpoints so that the images of multiple viewpoints are unified into a standard world coordinate system.

[0015] In the above-mentioned rapid fusion device for multi-viewing angle panoramic measurement at a complex test site, the rapid fusion device is made of alloy material.

[0016] The utility model has the following advantages:

[0017] (1) The utility model discloses a fast fusion device for multi-view panoramic measurement of complex test sites, which uses a precision-machined three-dimensional device for fusion processing, effectively improving the full-field measurement accuracy after fusion.

[0018] (2) The utility model discloses a fast fusion device for multi-view panoramic measurement of complex test sites. Camera groups with different viewpoints do not need to have overlapping observation areas, thereby effectively increasing the effective format of the camera and effectively reducing the error sources in the multi-view fusion process.

[0019] (3) The utility model discloses a rapid fusion device for multi-view panoramic measurement of complex test sites, which uses polyhedron configurations with different numbers of faces and devices of different sizes, and can be applied to different wind tunnel measurement scenarios and refined requirements for measurement accuracy.

[0020] (4) The utility model discloses a rapid fusion device for multi-view panoramic measurement of complex test sites, which utilizes the inherent relationship of precision-machined polyhedrons and precision-machined coordinate systems to perform coordinate system conversion, which is simple and efficient.

[0021] (5) The utility model discloses a rapid fusion device for multi-view panoramic measurement of complex test sites, which has a simple structure, is easy to operate and has high processing efficiency, and can effectively improve the reliability and accuracy of multi-view full-field measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of a fast fusion device for multi-view panoramic measurement of complex test sites in an embodiment of the utility model. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present utility model clearer, the implementation methods disclosed in the present utility model will be further described in detail below with reference to the accompanying drawings.

[0024] One of the core ideas of the utility model is that in the wind tunnel test, the multi-view fusion device is simplified into a precision-machined reference device, each face of the polyhedron is a reference surface, and the high-precision coordinate axis system can also be extracted with high precision by image processing; the high-precision coordinate axis system of each reference surface can be easily and quickly unified into the world coordinate system, so as to fuse the measurement results of multiple viewpoints together and realize fast multi-view morphology and deformation measurement. This fast fusion device for multi-view panoramic measurement of complex test sites is particularly suitable for all-round morphology and deformation measurement in wind tunnel tests.

[0025] Reference Figure 1 In this embodiment, the rapid fusion device for multi-view panoramic measurement of complex test sites is a long strip calibration block with a polyhedron cross section, which can be made of alloy material. Among them, the multiple circumferential surfaces of the calibration block are reference surfaces 1, and the reference surface 1 is processed with a coordinate system groove 2 of a given depth and width. The end face of the calibration block is a reference surface 3, and the center position of the reference surface 3 is processed with a standard threaded hole 4, through which the calibration block can be connected and fastened with other tooling. The surfaces of the reference surface 1 and the reference surface 3 are made with speckles suitable for specific tests. For example, in a high-temperature environment, a high-temperature resistant coating needs to be selected for speckle production.

[0026] In this embodiment, the rapid fusion device can realize multi-perspective panoramic measurement of complex test sites, and realize rapid fusion processing with extremely high reliability. Before the test, the rapid fusion device is installed at the test position of the object to be measured, and a camera group arranged all around is used to synchronously take pictures of the rapid fusion device with speckle, and obtain multiple pictures in all directions; then, the camera groups in various directions are calibrated separately, and after the calibration is completed, they are converted to the coordinate system of their corresponding reference planes; finally, the coordinate systems of multiple reference planes are unified into a world coordinate system, and the rapid fusion processing of multiple perspectives of complex test sites can be realized. The test requires: the field of view of the camera at a certain perspective needs to fully cover at least one reference plane 1 of the rapid fusion device.

[0027] In this embodiment, the reference coordinates of each reference surface 1 are directly processed into the coordinate system grooves 2 on the surface. Coordinate system grooves of different accuracy levels can be processed according to the specific measurement accuracy requirements of the test. The width and depth of the coordinate system grooves are determined by the measurement accuracy. Generally, the width and depth of the coordinate system grooves are set to correspond to about 1 to 2 pixels in the image.

[0028] In this embodiment, a rapid fusion device having substantially the same size as the test specimen may be selected according to the specific size requirements of the test specimen, that is, the size ratio of the rapid fusion device to the test specimen is generally 1:1.

[0029] In this embodiment, speckles of different characteristics and sizes can be produced according to the specific requirements of the test field size. The size of the speckle generally corresponds to 3 to 5 pixels in the image, and the shape of the speckle is obtained randomly.

[0030] In this embodiment, during the test, the coordinate transformation relationship corresponding to the reference surface 3 of the rapid fusion device can be used to perform coordinate transformation on the images of multiple perspectives, so that the images of multiple perspectives are unified into a standard world coordinate system.

[0031] Based on the above embodiment, a specific example is described below.

[0032] Step 1: According to the need of measuring the field of view in the wind tunnel test, a calibration block (i.e., a rapid fusion device) of corresponding size is manufactured. For example, the field of view of this test is about 200mm*200mm*300mm, and the position and range of the observation angle are limited, so the calibration block is designed as a hexagonal strip with a cross section of 150mm*150mm*200mm.

[0033] Step 2: According to the measurement accuracy requirements of the wind tunnel test, coordinate system grooves with a depth and width of 0.2mm are processed at a certain distance close to the edge of the six reference surfaces of the calibration block, and the processing accuracy is 0.01mm.

[0034] Step 3: According to the size and type of the test model, corresponding speckles are made on the six datum surfaces and reference surface of the calibration block. The speckles are composed of randomly distributed black and white spots, and the speckles are irregular spots with a diameter of 0.05mm to 0.5mm.

[0035] Step 4: Process a threaded hole at the center of the reference surface of the calibration block.

[0036] Step 5: Arrange multiple camera groups circumferentially at the wind tunnel test site.

[0037] Step 6: Install the prepared calibration block at the installation position of the test piece to be measured, and position and tighten it through the threaded holes, and ensure that the calibration block can be imaged within the effective field of view of the camera group at each viewing angle.

[0038] Step 7: Calibrate the measurement system and quickly unify the coordinate systems of each perspective into the world coordinate system based on the coordinate transformation relationship corresponding to each reference surface on the calibration block.

[0039] Step 8: Use the synchronous trigger device to issue instructions to all camera groups, and use the camera groups arranged in all directions to synchronously take pictures of the calibration block to obtain multiple pictures in all directions at the same time; calibrate the camera groups in each direction separately, and convert them to the coordinate system of their corresponding reference surface after calibration; finally, perform coordinate transformation according to the conversion relationship, and the coordinate values ​​calculated from the images collected by all camera groups are world coordinates, which can realize the rapid fusion processing of multi-view panoramic measurement of complex scenes.

[0040] The above is only the best specific implementation method of the utility model, but the protection scope of the utility model is not limited to this. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the utility model should be covered by the protection scope of the utility model.

[0041] The contents not described in detail in the utility model specification belong to the common knowledge of the professional and technical personnel in this field.

Claims

1. A fast fusion device for multi-view panoramic measurement of complex test sites, characterized in that: The rapid fusion device is a long strip calibration block with a polyhedral cross section; Multiple circumferential surfaces of the calibration block are reference surfaces (1), and a coordinate system groove (2) with a given depth and width is machined on the reference surface (1); The end face of the calibration block is a reference surface (3), and a standard threaded hole (4) is machined at the center of the reference surface (3); The surfaces of the reference surface (1) and the reference surface (3) are provided with speckles suitable for testing.

2. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The reference coordinates of each reference surface (1) are directly processed into a coordinate system groove (2) on the surface.

3. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The size ratio of the rapid fusion device to the test specimen is 1:

1.

4. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The test requires that the field of view of the camera at a certain viewing angle needs to fully cover at least one reference surface (1) of the rapid fusion device.

5. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The size of the speckle corresponds to 3 to 5 pixels in the image, and the shape of the speckle is obtained randomly.

6. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The width and depth of the coordinate system groove (2) both correspond to 1 to 2 pixels in the image.

7. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: During the test, the coordinate transformation relationship corresponding to the reference surface (3) of the rapid fusion device is used to transform the coordinates of the images of multiple viewing angles, so that the images of multiple viewing angles are unified into a standard world coordinate system.

8. The rapid fusion device for multi-view panoramic measurement of complex test sites according to claim 1 is characterized in that: The rapid fusion device is prepared from alloy materials.

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