A grating binocular stereo vision three-dimensional measurement system and method

Abstract

The present invention discloses a grating binocular stereoscopic vision three-dimensional measurement system and method, which relates to the field of three-dimensional measurement technology, including an optical measurement device, a plane target, a control acquisition system, a processing computer and a driving device, wherein the optical measurement device and the plane target are distributed around the object to be measured, and the optical measurement device and the plane target are connected to the control acquisition system and the processing computer, wherein: the optical measurement device is a grating binocular vision sensor, a grating laser emitting device, an industrial camera and a fill light source device, the grating laser emitting device emits multiple groups of lasers toward the object to be measured, and the grating binocular vision sensor is used to collect image data. The present invention has the advantages of relatively convenient operation, and global calibration is performed in advance through the cooperation of the plane target and the optical measurement device, and has a better practical effect.

Description

Technical Field

[0001] The present invention relates to the field of three-dimensional measurement technology, and in particular to a grating type binocular stereo vision three-dimensional measurement system and method. Background Art

[0002] Grating binocular stereo vision technology can capture and collect three-dimensional information on the surface of an object with high accuracy, and is widely used in various fields of precision measurement.

[0003] The existing measurement system process is complex, the calculation is cumbersome, and a lot of time is wasted during calibration. Summary of the invention

[0004] The purpose of the present invention is to provide a grating type binocular stereoscopic vision three-dimensional measurement system and method, which has the advantages of relatively convenient operation, and pre-global calibration through the cooperation of a plane target and an optical measuring device, has better practicality, and solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides a grating type binocular stereoscopic vision three-dimensional measurement system, comprising an optical measurement device, a plane target, a control and acquisition system, a processing computer and a driving device, wherein the optical measurement device and the plane target are distributed around the object to be measured, and the optical measurement device and the plane target are connected to the control and acquisition system and the processing computer, wherein:

[0006] The optical measuring device includes a grating binocular vision sensor, a grating laser emitting device, an industrial camera and a fill light source device. The grating laser emitting device emits multiple groups of lasers toward the object to be measured, and the grating binocular vision sensor is used to collect image data.

[0007] The processing computer drives the control acquisition system to light up the feature points on the planar target, uses the optical measuring device to measure the planar target, and performs three-dimensional scanning and measurement on the object to be measured. Using the planar target as a medium, the three-dimensional detection data obtained by the optical measuring device is summarized and transmitted to the control acquisition system and the processing computer.

[0008] The control acquisition system performs center point matching on the acquired image data.

[0009] The processing computer uses the obtained light strip data as matching points to match the matching points and construct

[0010] Establish matching point pairs, generate multiple groups of measurement models based on the matching point pairs, and obtain the corresponding three-dimensional coordinates in space.

[0011] Optionally, the extraction algorithm module in the control acquisition system is based on the Harris Cocner corner point extraction method, and performs sub-pixel corner point extraction and calculation to obtain the coordinates of the center of the calibrated template image, so as to construct a set of feature points.

[0012] Optionally, when the optical measuring device is used, it adjusts and calibrates its internal parameters in advance, and identifies and locates the feature points of the planar target.

[0013] Optionally, the grating binocular vision sensor specifically collects matching results of light strip images through two measuring cameras and calculates local three-dimensional measurement data.

[0014] Optionally, the planar target includes a cursor target and a metal frame, the metal frame is used to fix the cursor target and is configured with an active power supply device, and the cursor target adopts a high-voltage resistant and high-protection package.

[0015] A grating binocular stereo vision three-dimensional measurement method, the steps are as follows:

[0016] Step S1: components and preparation, including optical measurement device, planar target, control acquisition system, processing computer and drive device;

[0017] Step S2: pre-adjustment, adjusting the distance between the optical measuring devices according to the geometric dimensions of the object to be measured;

[0018] Step S3: calibration and processing, collecting images of the target plate through the optical measuring device and the plane target to obtain an image pair; calibrating the optical measuring device through a two-step method, further obtaining the internal and external parameters of the optical measuring device and determining the specific spatial relationship of the optical measuring device;

[0019] Step S4: Image acquisition and analysis: two optical measuring devices are used to shoot the object to be measured to obtain an image pair of the object to be measured; the optical measuring device emits a light bar to the object to be measured, and performs image acquisition and processing; finally, the acquired image data is processed, automatically classified and uploaded to the storage device.

[0020] in the database of the management computer;

[0021] Step S5: Generate results and obtain three-dimensional measurement data of the object to be measured. Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. The present invention improves the acquisition speed and the matching efficiency after acquisition, and can accurately acquire data images even when blocked, so as to avoid the large amount of calculation and the large amount of redundancy that may occur in the existing system during acquisition. This method uses two optical measurement devices to fuse multiple groups of measurement models, so there is no need for multiple scans, and uses a plane target as a medium to aggregate the locally acquired data into the overall coordinates. This system has the characteristics of high measurement accuracy, little influence, and fast processing and acquisition speed.

[0023] Second, the present invention can assist the binocular vision sensor in collecting data by setting up a supplementary light source device, avoid collecting shadows due to environmental factors, avoid multiple collections, and improve work efficiency.

[0024] 3. The present invention uses two measuring cameras and a panoramic camera to accurately collect data on objects, form multiple groups of image pairs, and perform pairing and comparison, thereby improving the accuracy of measurement.

[0025] Fourth, the present invention can independently realize wide-range and blind-angle-free video recording through the setting of a panoramic camera, which has the effect of reducing errors and improving accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a grating type binocular stereo vision three-dimensional measurement system and method of the overall implementation flow chart;

[0027] Figure 2 is a flow chart of the measuring method of the present invention;

[0028] Figure 3 It is a schematic diagram of the structure of the optical measuring device of the present invention.

[0029] In the figure: 1. Optical measuring device; 2. Planar target; 3. Control and acquisition system; 4. Processing computer; 5. Driving device; 6. Grating binocular vision sensor; 7. Grating laser emitting device; 8. Industrial camera; 9. Fill light source equipment. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] See also Figures 1 to 3The present invention provides a grating binocular stereoscopic vision three-dimensional measurement system, comprising an optical measurement device 1, a plane target 2, a control and acquisition system 3, a processing computer 4 and a driving device 5. The optical measurement device 1 and the plane target 2 are distributed around the object to be measured. The optical measurement device 1 and the plane target 2 are connected to the control and acquisition system and the processing computer 4. The use of the optical measurement device and the plane target can complete the global calibration in advance, and there is no need to recalibrate on site. The control system and the processing computer perform centralized processing on data and images. The driving device is used to drive the system to operate, which is convenient for users to control.

[0032] The optical measuring device 1 includes a grating binocular vision sensor 6, a grating laser emitting device 7, an industrial camera 8 and a fill light source device 9. The grating laser emitting device 7 emits multiple groups of lasers toward the object to be measured. The grating binocular vision sensor 6 is used to collect image data. The fill light source device can assist the binocular vision sensor in collecting data, avoid collecting shadows due to environmental factors, avoid multiple collections, and improve work efficiency.

[0033] The processing computer 4 drives the control acquisition system to light up the feature points on the plane target 2, and uses the optical measuring device 1 to measure the plane target, and performs three-dimensional scanning and measurement on the object to be measured. Using the plane target 2 as a medium, the three-dimensional detection data obtained by the optical measuring device 1 is summarized and transmitted to the control acquisition system 3 and the processing computer 4.

[0034] The control acquisition system 3 performs center point matching on the acquired image data. For each center point, the processing computer 4 uses the acquired light strip data as a matching point, performs matching point matching and constructs matching point pairs, generates multiple groups of measurement models based on the matching point pairs, and obtains the corresponding three-dimensional spatial coordinates. This system has the advantages of improving the acquisition speed and matching efficiency after acquisition, and can accurately acquire data images even when blocked, so as to avoid the large amount of calculation and the occurrence of a large amount of redundancy in the existing system during acquisition.

[0035] In this case, this method uses two optical measuring devices to fuse multiple groups of measurement models, so there is no need for multiple scans, and with the plane target as the medium, the locally collected data is summarized into the overall coordinates. This system has the characteristics of high measurement accuracy, small influence and fast processing and acquisition speed.

[0036] Furthermore, the extraction algorithm module in the control acquisition system 3 is based on the Harris Cocner corner point extraction method, and performs sub-pixel corner point extraction and calculation to obtain the coordinates of the center of the calibrated template image, so as to construct a set of feature points.

[0037] Furthermore, when the optical measuring device 1 is used, its internal parameters are adjusted and calibrated in advance, and characteristic points of the planar target are identified and located, so as to improve the detection efficiency and reduce the error.

[0038] Furthermore, the grating type binocular vision sensor 6 specifically collects the matching results of the light strip images through two measuring cameras and calculates the local three-dimensional measurement data, so as to facilitate the reconstruction and fusion of the results of the measurement model of multiple sets of data acquisition devices on the grating type binocular vision sensor. Therefore, there is no need to scan multiple times, and the complete three-dimensional information of the object surface can be obtained.

[0039] Furthermore, the planar target 2 includes a cursor target and a metal frame. The metal frame is used to fix the cursor target and is equipped with an active power supply device. The cursor target adopts a high-voltage resistant and highly protected package. The active cursor target has the characteristics of easy identification, high precision and small size. It is used to establish a dynamic reference coordinate system to eliminate measurement errors caused by external factors.

[0040] Furthermore, the panoramic camera can independently realize wide-range shooting without blind spots, which has the effect of reducing errors and improving accuracy.

[0041] A grating binocular stereo vision three-dimensional measurement method, the steps are as follows:

[0042] Step S1: components and preparation, including an optical measuring device 1, a planar target 2, a control and acquisition system 3, a processing computer 4 and a driving device 5;

[0043] Step S2: pre-adjustment, adjusting the distance between the optical measuring devices according to the geometric dimensions of the object to be measured, so that the measured data is more accurate;

[0044] Step S3: calibration and processing, the target plate is imaged by the optical measuring device 1 and the plane target 2 to obtain an image pair; the optical measuring device is calibrated by a two-step method, the internal and external parameters of the optical measuring device are further obtained and the specific spatial relationship of the optical measuring device is determined, the target plate is first placed in the shooting area of ​​the two optical measuring devices, and the image of the target plate is collected to obtain an image pair; the two optical measuring devices and the plane target are calibrated by the two-step method to obtain the internal and external data of the optical measuring device, and the calibration result shows an error of 0.14%-0.55%;

[0045] Step S4: image acquisition and analysis, the object to be measured is photographed by two optical measuring devices 1 to obtain an image pair of the object to be measured; the optical measuring device 1 emits a light bar to the object to be measured, and performs image acquisition and processing; the image data obtained are finally processed, automatically classified and uploaded to the database of the processing computer 4 for storage, the object to be measured is placed within the shooting range of the two optical measuring devices, and the two optical measuring devices simultaneously photograph the surface of the object to be measured to obtain image data and image pairs, the image pairs obtained in step S3 are used to obtain the coordinates of the feature points of the object to be measured by using the phase encoding and unfolding theory method, and the numerical interpolation method is used to obtain all the sub-pixel feature points in the image of the object to be measured, and then the matching feature points are obtained in another image of the image of the object to be measured through the feature points;

[0046] Step S5: Generate results and obtain three-dimensional measurement data of the object to be measured, based on the obtained feature points to obtain the three-dimensional measurement data.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A grating binocular stereo vision three-dimensional measurement method; characterized in that: A grating type binocular stereoscopic vision three-dimensional measurement system is provided, the system comprising an optical measurement device (1), a plane target (2), a control and acquisition system (3), a processing computer (4) and a driving device (5), the optical measurement device (1) and the plane target (2) are distributed around the object to be measured, the optical measurement device (1) and the plane target (2) are connected to the control and acquisition system and the processing computer (4), wherein: The optical measuring device (1) comprises a grating binocular vision sensor (6), a grating laser emitting device (7), an industrial camera (8) and a supplementary light source device (9), wherein the grating laser emitting device (7) emits a plurality of groups of lasers toward the object to be measured, and the grating binocular vision sensor (6) is used to collect image data. Specifically, the grating binocular vision sensor (6) collects matching results of light strip images through two measuring cameras and calculates local three-dimensional measurement data. The grating binocular vision sensor (6) is a panoramic camera and a measuring camera, and accurately collects data on the object through the two measuring cameras and the panoramic camera, and forms a plurality of image pairs, which are then matched and compared. The processing computer (4) drives the control acquisition system to illuminate the feature points on the planar target (2), and uses the optical measurement device (1) to measure the planar target, and performs three-dimensional scanning and measurement on the object to be measured. The three-dimensional detection data obtained by the optical measurement device (1) is summarized using the planar target (2) as a medium, and is transmitted to the control acquisition system (3) and the processing computer (4); The control acquisition system (3) performs center point matching on the acquired image data. For each center point, the processing computer (4) uses the acquired light strip data as a matching point, performs matching point matching and constructs matching point pairs, generates multiple groups of measurement models based on the matching point pairs, and obtains the corresponding three-dimensional spatial coordinates; A grating type binocular stereo vision three-dimensional measurement method, the steps comprising: Step S1: components and preparation, including an optical measuring device (1), a planar target (2), a control acquisition system (3), a processing computer (4) and a driving device (5); Step S2: pre-adjustment, adjusting the distance between the optical measuring devices according to the geometric dimensions of the object to be measured; Step S3: calibration and processing, collecting images of the target plate through the optical measuring device (1) and the plane target (2) to obtain an image pair; calibrating the optical measuring device through a two-step method, further obtaining internal and external parameters of the optical measuring device and determining the specific spatial relationship of the optical measuring device; Step S4: image acquisition and analysis, using two optical measuring devices (1) to shoot the object to be measured to obtain an image pair of the object to be measured; the optical measuring device (1) emits a light bar to the object to be measured, and performs image acquisition and processing; finally, the acquired image data is processed, automatically classified and uploaded to a database of a processing computer (4); Step S5: Generate results and obtain three-dimensional measurement data of the object to be measured.

2. The grating type binocular stereo vision three-dimensional measurement system according to claim 1, characterized in that: The extraction algorithm module in the control acquisition system (3) is based on the Harris Cocner corner point extraction method, and performs sub-pixel corner point extraction and calculation to obtain the coordinates of the center of the calibrated template image, so as to construct a set of feature points.

3. The grating type binocular stereo vision three-dimensional measurement system according to claim 1, characterized in that: When the optical measuring device (1) is in use, its internal parameters are adjusted and calibrated in advance, and the characteristic points of the planar target are identified and located.

4. The grating type binocular stereo vision three-dimensional measurement system according to claim 1, characterized in that: The planar target (2) comprises a cursor target and a metal frame, the metal frame is used to fix the cursor target and is equipped with an active power supply device, and the cursor target adopts a high-voltage resistant and high-protection package.

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