Detection system and device for triangulation distance measurement of vehicle-mounted camera module

Abstract

The invention relates to the technical field of camera testing, in particular to a vehicle-mounted camera module triangulation range finding detection system and device. Comprising a serialization board which is connected with a vehicle-mounted camera module and converts a parallel signal output by the camera module into a serial signal; the decoding board is connected with the serialization board and used for restoring the serial signals into parallel signals; the degree box is connected with the decoding deck and is used for further processing the decoded signals and converting the decoded signals into image data formats which can be identified by a computer; the total station is used for measuring space coordinates of the left target, the right target and the vehicle-mounted camera module, and a checkerboard graph card is adopted as the test target; the distance between the left target and the product, the distance between the right target and the product and the distance between the left target and the right target are calculated through the triangulation ranging principle and coordinate values measured by the total station, and software parameters are adjusted according to the calculated distances. According to the technical scheme, the testing process of the vehicle-mounted camera module can be simplified, and the testing efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of camera testing, and in particular to a detection system and device for triangulation ranging of a vehicle-mounted camera module. Background Art

[0002] With the rapid development of intelligent automobile technology, vehicle-mounted cameras are key components of autonomous driving and assisted driving systems, and their performance stability and accuracy are crucial to ensure driving safety. Vehicle-mounted camera modules are not only required to have high-resolution image acquisition capabilities, but also need to be able to provide accurate ranging information in various complex environments to support vehicle path planning, obstacle detection and avoidance, and other functions.

[0003] Traditionally, vehicle-mounted camera modules use a triangulation system to measure distance. This method relies on the geometric relationship between two or more optical targets (usually checkerboard cards) with known positions and the camera module to determine the distance of the target object by calculating the parallax in the image. However, the traditional triangulation system faces many problems in practical applications: Traditional systems require precise adjustment of the baseline length and angle of the two targets. This process is not only cumbersome, but also requires extremely high installation accuracy, which greatly increases the time cost of system deployment.

[0004] In order to obtain more accurate ranging results, traditional methods generally require collecting checkerboard images multiple times and performing repeated tests in different environments. This is not only cumbersome, but also limits test efficiency.

[0005] The fixed-structure target system is difficult to adapt to the baseline length requirements of different vehicle models or different application scenarios, which limits the versatility and flexibility of the system.

[0006] To achieve high-precision distance measurement, traditional systems often use hardware devices such as high-precision guide rails and servo motors. These components significantly increase the overall cost of the system.

[0007] Due to the accuracy limitations of the rangefinder itself, insufficient laser intensity or environmental factors (such as lighting conditions), the actual test error of the traditional triangulation ranging system is large and it is difficult to meet the requirements of high-precision ranging.

[0008] Slight deviations in the focal length adjustment or installation angle of the camera module may cause nonlinear distortion of the ranging results, further affecting the accuracy of the ranging. Summary of the invention

[0009] The purpose of the present invention is to propose a detection system and system for triangulation ranging of a vehicle-mounted camera module. The technical solution can simplify the testing process of the vehicle-mounted camera module and improve the testing efficiency.

[0010] To achieve the above-mentioned object, in a first aspect, the present invention provides a detection device for triangulation ranging of a vehicle-mounted camera module, comprising: a serialization board connected to the vehicle-mounted camera module, converting a parallel signal output by the camera module into a serial signal; A decoding board, connected to the serialization board, is used to restore the serial signal to a parallel signal; The signal box is connected to the decoding board and is used to further process the decoded signal and convert it into an image data format that can be recognized by the computer; Total station, used to measure the spatial coordinates of the left target, right target and vehicle-mounted camera module. The test target uses a chessboard chart; Based on the principle of triangulation and using the coordinate values ​​measured by the total station, the distances from the left target to the product, the right target to the product, and between the left and right targets are calculated, and the software parameters are adjusted based on the calculated distances.

[0011] Beneficial effects of the basic solution: The parallel signal output by the camera module is converted into a serial signal through the serialization board, which reduces the number of transmission lines, reduces signal interference, achieves long-distance stable transmission, ensures reliable transmission of image signals from the camera module to subsequent devices, and improves data transmission efficiency and stability.

[0012] The decoder board restores the serial signal to a parallel signal, which is further processed and converted into an image data format that can be recognized by the computer by the signal box, so that the computer can accurately process and display the image collected by the camera module, providing a clear and accurate image data basis for subsequent analysis and testing.

[0013] The total station can accurately measure the spatial coordinates of the left target, right target and vehicle-mounted camera module, providing high-precision position data for subsequent calculations based on the principle of triangulation, which helps to accurately evaluate the performance of the vehicle-mounted camera module.

[0014] Through the principle of triangulation, the coordinate values ​​measured by the total station are used to calculate the relevant distances, and the software parameters are adjusted accordingly. This can achieve accurate calibration and testing of the vehicle camera module, improve the accuracy and reliability of the camera module's triangulation, and thus enhance the performance of the vehicle camera in actual applications.

[0015] This technical solution integrates multiple links such as signal transmission processing, spatial coordinate measurement, triangulation calculation and software parameter adjustment, forming a relatively complete vehicle camera module testing system. It can conduct comprehensive and reliable testing of vehicle camera modules, timely discover and solve potential problems, and ensure product quality.

[0016] As an implementable preferred solution, it also includes a pin fixture for fixing the vehicle-mounted camera module to ensure close fit with the interface of the camera module; the rotation angle of the camera module is controlled by the pin fixture rotation angle operation control system, and the operation control system is controlled by a motor through the three axes of the Razer shaft clamp.

[0017] As an implementable preferred solution, a tripod is also included to fix the total station to ensure that the total station remains stable during the measurement process.

[0018] As an implementable preferred solution, the method comprises the following steps: The total station measures the coordinates of the left target, right target and vehicle-mounted camera module products respectively; Input the measured coordinate values ​​into the computer and calculate the distance between each point; Adjust software parameters according to the calculated distance; Preview and fine-tune the position and angle of the camera module through software to obtain multiple sets of grab frame coordinate positions; Adjust the acquired grab frame coordinates and size, and adjust the yaw angle, pitch angle, and roll angle of each position of the camera module until the optimal state is reached; Test by shooting targets at different positions in the camera module's field of view to ensure stable illumination during shooting.

[0019] As an implementable preferred solution, the distance calculation formula includes: Left target To module :

[0020] Right target To module :

[0021] Between left and right targets: .

[0022] As an implementable preferred solution, the software parameters are adjusted, including the adjustment of 16 groups of grab frame coordinates, and the adjustment of the yaw angle, pitch angle, and roll angle of each group of positions.

[0023] As an implementable preferred solution, the camera module FOV shoots 2 targets at different positions, in the order of first shooting 9 positions horizontally and then shooting 7 positions vertically, for a total of 16 positions.

[0024] As a feasible preferred solution, ensure that the illumination in the test area is within the range of 500-1000 lux.

[0025] As an implementable preferred solution, COD Sample is used to generate images in real time, preview and fine-tune the position and angle of the camera module.

[0026] In a second aspect, the present invention further provides a vehicle-mounted camera module triangulation ranging detection system, which utilizes the above-mentioned vehicle-mounted camera module triangulation ranging detection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Build a block diagram for triangulation hardware.

[0028] Figure 2 This is the first installation diagram of the foot screw.

[0029] Figure 3 This is the second installation diagram of the foot screw.

[0030] Figure 4 This is a schematic diagram of the total station angle measurement mode interface.

[0031] Figure 5 Schematic diagram for software parameter adjustment.

[0032] Figure 6 This is a relationship diagram of the target corresponding test position.

[0033] Figure 7 This is a schematic diagram for debugging the pitch axis, yaw axis, and roll axis parameters. DETAILED DESCRIPTION

[0034] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings. It will be understood that the specific embodiments described herein are only partial embodiments of the present invention, which are only used to explain the present application, rather than to limit the present application. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered isolated, and they can be combined with each other to achieve better technical effects. The same reference numerals appearing in the drawings of the following embodiments represent the same features or components, which can be applied to different embodiments.

[0035] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of the present invention should have the common meanings understood by those skilled in the art in the art to which the present invention belongs.

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings: Reference numerals: electronic device 500 , processor 501 , communication interface 502 , memory 503 , bus 504 .

[0037] Reference Figure 1The embodiment of the present disclosure provides a detection device for triangulation ranging of a vehicle-mounted camera module, including a total station, a computer, a USB cable, a degree box, a decoding board, a serialization board, a FaKra cable, a pin fixture, a camera module, and a chessboard chart.

[0038] The size of the chessboard chart is 700mm, and the grid size is 300mm. The camera module is installed on the ejector fixture. The ejector fixture is made of precision-machined metal material to ensure close fit with the interface of the camera module and play a stable fixing role. The ejector fixture is customized according to different models of camera modules to meet the testing needs of various vehicle-mounted cameras.

[0039] The camera module is connected to the Duxin box and the serialization board through the FaKra cable to ensure the stability of signal transmission. The Duxin box is responsible for the preliminary processing of the signal output by the camera module, and the serialization board transmits the processed signal in serial form so that subsequent devices can receive it. Then use the coaxial cable to connect the serialization board to the decoder board, which decodes the serial signal into an image data format that can be recognized by the computer. Finally, the decoder board is connected to the computer through a USB cable to realize the transmission and processing of image data.

[0040] The steps for the vehicle camera module triangulation test are as follows: When the total station is used for triangulation, the coordinates of the left target, right target, and product need to be measured respectively, so as to calculate the distance between them. The calculation method is to fill the coordinate values ​​of the three points into the corresponding positions of the distance calculation page. When placing the total station, it is necessary to pay attention to the fact that there should be no obstruction on the line connecting the target to be measured. The specific test process is as follows: Step S1, open the tripod, make the three legs of the tripod approximately equidistant, and the top surface approximately horizontal, and then fix the tripod. Place the total station on the top surface of the tripod, and tighten the connection screws below the top surface of the tripod to fix the total station.

[0041] Step S2, there are three screws at the bottom of the total station for adjusting the level. Figure 2 First, rotate the total station so that the built-in level is parallel to the line connecting the foot screws AB. Then adjust AB so that the bubble of the level is in the center.

[0042] Step S3, refer to Figure 3 , rotate the total station 90° so that the level is perpendicular to the line connecting the foot screws AB. Then adjust the foot screw C so that the bubble of the level is in the center.

[0043] Step S4, remove the protective cover of the objective lens, point the lens at the white background, and observe through the eyepiece. Rotate the eyepiece tube to adjust the diopter until the crosshairs can be clearly seen.

[0044] Step S5, use the crosshairs in the rough aimer to aim at the target point. After roughly aiming, the horizontal stop handwheel and the vertical stop handwheel can be rotated to fix the angle.

[0045] Step S6, observe from the eyepiece, rotate the focus handwheel until the target point is clearly imaged. Then rotate the horizontal fine-tuning handwheel and the vertical fine-tuning handwheel for fine adjustment until the crosshairs are aligned with the target point. At this time, when the eye moves up and down, left and right at the eyepiece end, if parallax is found, it means that the diopter or focus is not adjusted properly, and fine adjustment is required.

[0046] Step S7, press and hold the total station power button to turn on the instrument, then press the CORD button to enter the angle measurement mode. Figure 4 Then press the corresponding measurement button to measure the coordinates (N, E, Z) of the target point. Fill in the corresponding values ​​in the distance calculation page of this form.

[0047] Step S8, release the horizontal stop handwheel and the vertical stop handwheel, repeat steps S5 to S7 for the next target point, and obtain the three values ​​N, E, and Z of the left target, right target, and camera module respectively. N (Northing) represents the northing coordinate, that is, the north-south distance of the measuring point relative to the origin of the coordinate system (usually in meters). In engineering measurement, the N axis points to the geographic north or coordinate north direction. E (Easting) represents the easting coordinate, that is, the east-west distance of the measuring point relative to the origin of the coordinate system. The E axis is perpendicular to the N axis and points to the east. Z (Elevation or Altitude) represents the elevation coordinate, that is, the vertical height (altitude or relative elevation) of the measuring point. The Z axis is perpendicular to the horizontal plane (NE plane), and the positive direction is upward.

[0048] Fill the left target, right target and product N, E, Z values ​​into the following formula: Left target To module :

[0049] Right target To module :

[0050] Between left and right targets:

[0051] Then calculate the distance from the left target to the right target and the distance from the product to the left and right targets, refer to Table 1.

[0052] Table 1

[0053] Adjust the software parameters according to the calculated distance, refer to Figure 5 .

[0054] Reference Figure 6 , target corresponding test position relationship diagram, adjust the 16 sets of grab frame coordinates to the most appropriate position in the FOV area, and then adjust the software parameters according to the 16 grab frame coordinates and sizes.

[0055] Use COD Sample to output the image in real time, click preview, and get the coordinate positions of the grab frame of the two bull's-eyes. By fine-tuning the position and angle of the camera module several times, 16 sets of grab frame coordinate positions are obtained in turn to ensure that the grab frame coordinates accurately cover the image area of ​​the target at different test positions.

[0056] Adjust the coordinates and sizes of the 16 grab frames. At the same time, adjust the yaw angle, pitch angle, and roll angle of each position of the 16 coordinates of the camera module. Figure 7 , adjust the module to the optimal position of the grab frame in real time, so that the grab frame can accurately frame the target and improve the accuracy of the measurement.

[0057] Turn the fixture angle and shoot 2 targets at different positions of the camera module FOV. The shooting distance is preferably 20 meters. Shoot in the order of shooting 9 positions horizontally first and then shooting 7 positions vertically, for a total of 16 positions.

[0058] The rotation angle of the camera module is controlled by the ejector fixture rotation angle control system. The control system is controlled by a motor through three axes of the Razer axis clamp. The ejector fixture fixes the camera module and can be a cavity or a clamp of matching size.

[0059] During the shooting process, the illumination was kept stable and the illumination of the test area was measured by a professional light meter to ensure that the illumination was within the range of 500 - 1000 lux to ensure that the corners of the chart could be clearly photographed.

[0060] The following is the internal calibration data EFL_X, EFL_Y, COD_X, COD_Y obtained by the vehicle camera module from eeprom; The triangulation result after K1, K2, K3, K4, K5, K6, P1, and P2 are subjected to distortion compensation (the process includes: the core of distortion compensation is to shoot the calibration plate through the camera; ② detect the corner points in the checkerboard of the calibration plate and obtain the pixel coordinates of these corner points; ③ obtain the distortion coefficients (radial distortion coefficient, tangential distortion coefficient) through calibration; ④ apply the distortion model to perform distortion correction on each pixel in the image; ⑤ perform distortion coefficient compensation on the corrected coordinates to generate a distortion-free image): EFL_x=7326.808402 EFL_y=7324.225398 COD_x=1905.422089 COD_y=1072.439959 k1=-17.182505 k2=235.987469 k3=-330.695889 k4=-16.988079 k5=233.113266 k6=-284.330420 p1=0.000316 p2=0.000659 RMS_Mean=0.000000 RMS_Max=0.000000 Triangulation GroupNum=16 Left mark point distance: 20017.000000mm, right mark point distance: 20015.000000mm, distance between left and right mark points 4188.000000mm, pupil distance compensation value 0.000000mm image1 L:(222.4,209.2)->(190.9,193.1), R:(1766.6,152.5)->(1766.1,149.3) Calculated distance: 4186.553711, calculated error = -0.035% image2 L:(2101.3,168.4)->(2101.8,165.3), R:(3648.3,138.8)->(3682.8,120.0) Calculated distance: 4187.723145, calculated error = -0.007% image3 L:(247.7,1943.9)->(217.8,1959.3), R:(1793.0,1916.1)->(1792.6,1918.3) Calculated distance: 4187.998535, calculated error = -0.000% image4 L:(2073.4,1961.8)->(2073.9,1964.4), R:(3619.7,1907.9)->(3650.2,1922.8) Calculated distance: 4187.149902, calculated error = -0.020% image5 L:(895.7,512.4)->(889.9,509.2), R:(2435.4,467.9)->(2436.6,466.4) Calculated distance: 4187.035645, calculated error = -0.023% image6 L:(1434.5,520.5)->(1433.5,519.3), R:(2975.3,479.7)->(2981.5,476.1) Calculated distance: 4187.845703, calculated error = -0.004% image7 L:(873.4,1604.8)->(867.6,1607.7), R:(2413.2,1565.9)->(2414.0,1566.8) Calculated distance: 4187.723145, calculated error = -0.007% image8 L:(1438.5,1617.5)->(1437.6,1618.5), R:(2978.9,1574.6)->(2984.6,1577.2) Calculated distance: 4187.692871, calculated error = -0.007% image9 L:(96.6,129.4)->(55.7,108.1), R:(136.1,1685.5)->(104.1,1696.4) Calculated distance: 4186.829102, calculated error = -0.028% image10 L:(3556.2,106.3)->(3586.1,88.4), R:(3602.0,1662.1)->(3627.8,1671.1) Calculated distance: 4188.380371, calculated error = 0.009% image11 L:(99.8,384.7)->(64.2,371.1), R:(148.3,1940.9)->(112.6,1958.2) Calculated distance: 4187.471191, calculated error = -0.013% image12 L:(3592.8,364.4)->(3620.0,352.7), R:(3630.4,1920.8)->(3661.8,1936.3) Calculated distance: 4188.013672, calculated error = 0.000% image13 L:(892.5,241.9)->(884.8,235.6), R:(936.8,1785.9)->(930.9,1790.1) Calculated distance: 4186.875000, calculated error = -0.027% image14 L:(2808.4,187.9)->(2814.1,182.0), R:(2852.0,1731.8)->(2856.8,1735.1) Calculated distance: 4187.494141, calculated error = -0.012% image15 L:(1864.5,238.7)->(1864.3,236.4), R:(1908.4,1775.5)->(1908.4,1776.8) Calculated distance: 4187.050781, calculated error = -0.023% image16 L:(1155.6,1110.1)->(1153.9,1110.1), R:(2693.4,1127.5)->(2695.1,1127.5) Calculated distance: 4188.082520, calculated error = 0.002% Coverage = 98.694% image1,Error=-0.035%,Spec=0.150%,PASS image2,Error=-0.007%,Spec=0.150%,PASS image3,Error=-0.000%,Spec=0.150%,PASS image4,Error=-0.020%,Spec=0.150%,PASS image5,Error=-0.023%,Spec=0.150%,PASS image6,Error=-0.004%,Spec=0.150%,PASS image7,Error=-0.007%,Spec=0.150%,PASS image8,Error=-0.007%,Spec=0.150%,PASS image9,Error=-0.028%,Spec=0.150%,PASS image10,Error=0.009%,Spec=0.150%,PASS image11,Error=-0.013%,Spec=0.150%,PASS image12,Error=0.000%,Spec=0.150%,PASS image13,Error=-0.027%,Spec=0.150%,PASS image14,Error=-0.012%,Spec=0.150%,PASS image15,Error=-0.023%,Spec=0.150%,PASS image16,Error=0.002%,Spec=0.150%,PASS Judging from the triangulation results of the above 16 points, they all meet the requirement of triangulation error ≤ 0.15%.

[0061] Those of ordinary skill in the art can understand that all or part of the process in a detection device for triangulation of a vehicle-mounted camera module can be completed by instructing related hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the process of each embodiment of a detection device for triangulation of a vehicle-mounted camera module. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0062] The disclosed embodiment also provides a vehicle-mounted camera module triangulation ranging detection system, which utilizes the above-mentioned vehicle-mounted camera module triangulation ranging detection device.

[0063] The above contents are only embodiments of the present invention. The common sense such as the known specific structures and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or the priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. A detection device for triangulation of a vehicle-mounted camera module, characterized in that: include: The serialization board is connected to the vehicle camera module to convert the parallel signal output by the camera module into a serial signal; A decoding board, connected to the serialization board, is used to restore the serial signal to a parallel signal; The signal box is connected to the decoding board and is used to further process the decoded signal and convert it into an image data format that can be recognized by the computer; Total station, used to measure the spatial coordinates of the left target, right target and vehicle-mounted camera module. The test target uses a chessboard chart; Based on the principle of triangulation and using the coordinate values ​​measured by the total station, the distances from the left target to the product, the right target to the product, and between the left and right targets are calculated, and the software parameters are adjusted based on the calculated distances.

2. The detection device for triangulation ranging of a vehicle-mounted camera module according to claim 1, characterized in that: It also includes a pin fixture for fixing the vehicle-mounted camera module to ensure close fit with the interface of the camera module; the rotation angle of the camera module is controlled by the pin fixture rotation angle operation control system, and the operation control system is controlled by a motor through the three axes of the Razer axis card.

3. The detection device for triangulation of a vehicle-mounted camera module according to claim 1, characterized in that: A tripod is also included to hold the total station in place, ensuring it remains stable during measurement.

4. A detection device for triangulation ranging of a vehicle-mounted camera module according to any one of claims 1 to 3, characterized in that: The usage steps include the following: The total station measures the coordinates of the left target, right target and vehicle-mounted camera module products respectively; Input the measured coordinate values ​​into the computer and calculate the distance between each point; Adjust software parameters based on the calculated distance; Preview and fine-tune the position and angle of the camera module through software to obtain multiple sets of grab frame coordinate positions; Adjust the acquired grab frame coordinates and size, and adjust the yaw angle, pitch angle, and roll angle of each position of the camera module until the optimal state is reached; Test by shooting targets at different positions in the camera module's field of view to ensure stable illumination during shooting.

5. The detection device for triangulation ranging of a vehicle-mounted camera module according to claim 4, characterized in that: The distance calculation formula includes: Left target To module : Right target To module : Between left and right targets: 。 6. The detection device for triangulation of a vehicle-mounted camera module according to claim 4, characterized in that: Adjust software parameters, including the adjustment of 16 groups of grab frame coordinates, and the adjustment of yaw angle, pitch angle, and roll angle of each group of positions.

7. The detection device for triangulation ranging of a vehicle-mounted camera module according to claim 4, characterized in that: The camera module shoots 2 targets at different positions of FOV, in the order of first shooting 9 positions horizontally and then shooting 7 positions vertically, for a total of 16 positions.

8. The detection device for triangulation ranging of a vehicle-mounted camera module according to claim 4, characterized in that: Ensure that the lighting in the test area is within the range of 500-1000 lux.

9. The detection device for triangulation ranging of a vehicle-mounted camera module according to claim 4, characterized in that: Use COD Sample to generate images in real time, preview and fine-tune the position and angle of the camera module.

10. A vehicle-mounted camera module triangulation detection system, characterized in that: A detection device for triangulation ranging of a vehicle-mounted camera module as described in any one of claims 1 to 9 is used.

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