Dynamic vehicle roof deformation measuring method based on three-dimensional multi-point optical system
By installing a three-dimensional multi-point optical system on the vehicle and using a high-speed camera and ARAMIS system for image data analysis, the problems of high installation difficulty, high cost and difficulty in capturing dynamic subtle deformation of traditional roof deformation measurement methods are solved, and comprehensive and accurate measurement of the roof is achieved, improving the accuracy and efficiency of measurement.
Patent Information
- Application Number
- CN202510110873.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-23
- Publication Date
- 2025-05-23
AI Technical Summary
The existing vehicle roof deformation measurement methods have problems such as high installation difficulty, high cost, difficulty in capturing dynamic subtle deformation, and are difficult to achieve comprehensive coverage and accurate measurement.
The dynamic vehicle roof deformation measurement method based on three-dimensional multi-point optical system is adopted. By installing the bottom optical system and the top optical system on the vehicle, image data analysis is performed using the on-board high-speed camera and professional measurement system ARAMIS to achieve accurate measurement of the displacement and strain of the roof surface.
The comprehensive coverage and accurate measurement of the inner surface of the roof are achieved, and the subtle deformation of the roof under dynamic conditions can be captured, the accuracy and efficiency of measurement is improved, the error rate is reduced, and scientific data support is provided for vehicle structure safety assessment and design optimization.
Smart Images
Figure CN120027721A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of vehicle safety assessment, and in particular to a dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system. Background Art
[0002] In the field of vehicle engineering and structural safety assessment, the deformation measurement of vehicle roofs has always been an important research topic. Although traditional measurement methods, such as physical contact sensors and strain gauges, can provide measurement data of roof deformation to a certain extent, they have many limitations. For example, physical contact sensors need to be directly pasted on the roof surface, which not only increases the difficulty and cost of installation, but may also interfere with the measurement results due to improper pasting or the weight of the sensor itself. In addition, traditional methods often have difficulty capturing subtle deformations under dynamic conditions, which limits their application in vehicle safety assessment, accident reconstruction, and design optimization.
[0003] With the continuous development of optical measurement technology, non-contact measurement methods based on optical principles have gradually emerged. However, there are still some problems in the application of existing optical systems in the deformation measurement of vehicle roofs. For example, how to ensure full coverage and accurate measurement of the entire inner surface of the roof, how to accurately capture subtle deformations under dynamic conditions, and how to simplify the installation process, reduce costs, and improve the stability and reliability of the measurement system. Summary of the invention
[0004] The purpose of the present invention is to propose a dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system, and the technical solution can improve the accuracy and efficiency of optical measurement technology.
[0005] To achieve the above objectives, the present disclosure provides a dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system, comprising: Install the optical system, including the bottom optical system and the top optical system, including: Install an on-board high-speed camera in the bottom optical system; set a black dot pattern on the top inner surface and surrounding parts of the A-pillar to the B-pillar on the front passenger side of the vehicle in the top optical system, and make the coverage area of the black dot pattern reach 40-50%, and the background is white; check the uniformity of black dot distribution, adjust the black dot diameter and distribution to meet the image analysis requirements; Calibration of optical systems, calibration of 3D multi-point optical systems using the ARAMIS measuring system; Process the optical system, start the on-board high-speed camera to record image data, and import the captured image data into the measurement system ARAMIS for analysis to obtain the displacement and strain of the roof surface and calculate the real-time deformation of the roof.
[0006] Beneficial effects of the basic solution: The three-dimensional multi-point optical system of this application achieves comprehensive coverage and accurate measurement of the entire inner surface of the roof. Compared with traditional methods, this method can not only capture the subtle deformation of the roof under dynamic conditions, but also ensure the comprehensiveness and accuracy of the measurement, providing strong data support for vehicle structural safety assessment, accident reconstruction and vehicle design optimization.
[0007] In terms of the installation of the optical hardware system, this technical solution is simple and efficient. The bottom optical system only needs to install an on-board high-speed camera, while the top optical system can be completed by setting a black dot pattern of a specific proportion on the top inner surface and surrounding parts of the A-pillar to the B-pillar on the front passenger side of the vehicle. The setting and adjustment of the black dot pattern have a certain degree of flexibility and can be customized according to specific vehicle and measurement requirements. It not only simplifies the operating process, reduces installation time and cost, but also ensures the stability and reliability of the measurement system, facilitating rapid deployment and flexible adjustment in practical applications. Since the measurement is based on optical principles, there is no need for direct contact with the object being measured, thus avoiding errors and possible damage caused by contact.
[0008] The present invention uses the professional measurement system ARAMIS to calibrate and process the three-dimensional multi-point optical system. By starting the on-board high-speed camera to record image data and importing it into the ARAMIS system for analysis, the displacement and strain of the roof surface can be quickly and accurately calculated, and the real-time deformation of the roof can be obtained. This not only improves the measurement accuracy and efficiency, but also effectively reduces the error rate, ensures the accuracy and credibility of the data, and provides a scientific basis for the evaluation of vehicle safety performance.
[0009] As an implementable preferred solution, a vehicle-mounted high-speed camera is installed on the bottom optical system, including the following: Select two vehicle-mounted high-speed cameras, equipped with reinforced lenses and camera brackets. The lenses use wide-angle lenses, and the camera brackets are equipped with LED lights and laser sights; Fix two vehicle-mounted high-speed cameras at a preset horizontal angle and install them on the camera bracket, adjust the distance between the camera lens and the inner surface of the roof, and ensure that the camera bracket is installed firmly; Adjust the LED light and laser aimer, and use the laser aimer to focus the two vehicle-mounted high-speed cameras on the same point.
[0010] As an implementable preferred solution, the three-dimensional multi-point optical system is calibrated using the measurement system ARAMIS, including the following: Set the measurement volume to ensure that the roof and surrounding key components are included in the measurement range; verify the accuracy of the distance from the camera lens to the measured point and the black spot diameter, adjust the coordinate system in the ARAMIS system, and convert it to the vehicle body coordinate system.
[0011] As an implementable preferred solution, the processing optical system includes: Start the on-board high-speed camera and synchronously record the image data 10ms before and 1000ms after the trigger at a rate of 1000Hz; Import the captured image data into a professional measurement system for analysis to obtain the displacement and strain of the roof surface; The image data is processed using algorithms in the measurement system ARAMIS, the real-time deformation of the roof is calculated, and the processed data is exported into an analysis format.
[0012] As an implementable preferred solution, the captured image data is imported into a professional measurement system for analysis to obtain the displacement and strain of the roof surface, including the following: The ARAMIS system identifies the surface structure of the object being measured in the camera image and compiles 2D coordinates for each pixel. The different 2D coordinates of the same pixel observed by the two cameras at the bottom are combined into a common 3D coordinate for analysis. The displacement and strain of the surface of the structure are obtained by identifying and calculating the grayscale changes of a single pixel combined with its coordinates.
[0013] As an implementable preferred solution, the real-time deformation of the roof is calculated, including the following contents: The image data is processed using the algorithm in the ARAMIS system to calculate the real-time deformation of the roof; the algorithm takes into account the camera's lens distortion and image noise.
[0014] As an implementable preferred solution, the real-time deformation of the roof is calculated, including the following contents: The 2D coordinates of each facet are combined into a common 3D coordinate using a photometric method.
[0015] The basic formula for three-dimensional coordinate calculation is:
[0016] in, are the three-dimensional coordinates of the small facet, and are the 2D coordinates in the left and right camera images, respectively. and is the rotation matrix of the camera.
[0017] As an implementable preferred solution, the calculation of the real-time deformation of the roof also includes the following contents: By comparing the 3D coordinates at different time steps, the deformation of the roof is calculated.
[0018] The calculation formula of deformation is:
[0019] in, is the deformation amount, and are the three-dimensional coordinates of two adjacent time steps.
[0020] As an implementable preferred solution, a rollover collision test is also performed, during which a three-dimensional multi-point optical system is activated to record the roof deformation in real time, including the following contents: Install the vehicle on the rollover crash test bench and adjust the test bench parameters; During the test, a three-dimensional multi-point optical system is activated to record the roof deformation in real time and other key parameters; Collect the roof deformation data during the entire rolling process, including deformation amount, deformation speed, and deformation direction.
[0021] As an implementable preferred solution, data analysis and evaluation are also included, including: Process and analyze the collected roof deformation data, calculate key parameters, and perform visualization; Assess the safety and stability of the vehicle structure in a rollover accident, check the deformation of the roof and passenger compartment, and analyze the occupants' survival space and injury risks. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Schematic diagram of the dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system.
[0023] Figure 2 Schematic diagram of the structure of the bottom optical system.
[0024] Figure 3 Schematic diagram of the top optical system. DETAILED DESCRIPTION
[0025] 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.
[0026] 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.
[0027] Reference numerals: vehicle-mounted high-speed camera 1 , connecting rod 2 , LED light 3 , laser aimer 4 .
[0028] The present invention is further described in detail below in conjunction with the accompanying drawings: Reference Figure 1 , a dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system, comprising: Step S100, refer to Figure 2 , install the optical system, including: Step S101, installing the bottom optical system, including: Step S101-1, select two vehicle-mounted high-speed cameras 1, each camera is equipped with a reinforced lens. In this embodiment, the focal length of the reinforced lens is 16 mm. A shorter focal length (such as 16 mm) can provide a wider field of view, so that the camera can simultaneously capture the deformation of multiple key parts such as the roof, roof rails, A-pillars and B-pillars. Prepare a stable steel camera bracket, which is divided into a bottom and a top, and the bottom and the top are connected by a connecting rod 2; install four high-intensity LED lights 3 and two laser sights 4 on the top of the camera bracket.
[0029] Step S101-2, fix the two vehicle-mounted high-speed cameras 1 at a preset horizontal angle. In this embodiment, the two vehicle-mounted high-speed cameras 1 are fixed at a horizontal angle of 21° relative to each other and are installed on a steel camera bracket. Since the optical system relies on the principle of stereoscopic vision measurement, the three-dimensional coordinates of the object can be calculated by capturing images of the same object from different angles with two cameras. A larger baseline angle can provide better depth perception, thereby improving the accuracy of the measurement, while an angle that is too large will result in the two cameras' fields of view not having a sufficiently large overlapping area, so 21° is a balance point.
[0030] Adjust the distance from the camera lens to the inner surface of the passenger side roof, which is 915 mm in this embodiment, to ensure that the camera bracket is firmly installed and fixed to the rigid structure of the vehicle floor by bolts.
[0031] Step S101-3, adjust the LED light 3 and the laser sight 4, turn on the high-intensity LED light 3 to ensure sufficient light to illuminate the inner surface of the roof. Use the laser sight 4 to focus the two on-board high-speed cameras on the same point, which is the middle position between the A-pillar roof surface and the B-pillar roof surface on the passenger side, so that as many parts as possible such as the roof, A / B pillars, and windshield are included in the shared field of view.
[0032] Step S102, installing the top optical system, including: Step S102-1, refer to Figure 3, prepare an optical pattern, set black dots on the top inner surface and surrounding parts from the A-pillar to the B-pillar on the front passenger side. The black dots can be set by spraying or mounting. According to the specific measurement requirements, it is necessary to find a balance between measurement accuracy and the feasibility of image processing. If the measurement accuracy requirements are extremely high, smaller black dots can be used, but it is necessary to ensure that the image resolution is high enough to support image processing. If the measurement accuracy requirements are relatively low, larger black dots can be used to improve the reliability and efficiency of image processing.
[0033] In this embodiment, the diameter of the black spot is 6 to 12 mm, ensuring that the pattern covers an area of about 40-50%, which is a balance between measurement accuracy and feasibility of image processing. The background is white to meet the requirements of the optical system.
[0034] Step S102-2, pattern layout and inspection, check the uniformity of black dot distribution, ensure that the grayscale variation of the pattern is sufficient so that it can be segmented into recognizable pixel units during image analysis. Adjust the black dot diameter and distribution so that each black dot corresponds to an average diameter of 4 to 8 pixels on the image.
[0035] Step S200, calibrating the optical system, includes: Step S201 , select the professional measurement system ARAMIS (Advanced Real-time Analysis and Measurement in Space, a three-dimensional measurement system based on digital image correlation technology) to ensure that the ARAMIS system can correctly identify and process the image data of the high-speed camera.
[0036] Step S202, using the ARAMIS system to calibrate the three-dimensional multi-point optical system; setting the measurement volume to approximately , ensuring that the roof and surrounding key components are included in the measurement range. The image of the high-speed camera is captured at a resolution of 915×915 pixels, and the average focal length from the measured pattern to the camera lens is 915 mm. Each pixel in the camera image corresponds to a 1.5×1.5mm square on the inner surface of the vehicle, ensuring image accuracy and resolution.
[0037] Step S203, verify the accuracy of the distance from the camera lens to the measured point and the diameter of the black spot, adjust the coordinate system in the ARAMIS system, and convert it to the vehicle body coordinate system to ensure that the measurement result is consistent with the actual vehicle structure.
[0038] Step S300, processing the optical system, includes: Step S301, start the vehicle-mounted high-speed camera 1, and synchronously record the image data of 10 ms before triggering and 1000 ms after triggering at a rate of 1000 Hz. The captured image data contains the dynamic change information of the inner surface of the roof, especially the displacement and strain of the black spot.
[0039] Step S302, importing the captured image data into the ARAMIS system for analysis; the ARAMIS system identifies the surface structure of the object under test in the camera image, compiles 2D coordinates for each pixel, and combines the different 2D coordinates of the same pixel observed by the two cameras at the bottom into a common 3D coordinate for analysis; the displacement and strain of the surface of the structure are obtained by identifying and calculating the grayscale change of a single pixel in combination with its coordinates.
[0040] Step S303, use the algorithm in the ARAMIS system to process the image data and calculate the real-time deformation of the roof; the algorithm takes into account factors such as camera lens distortion and image noise to ensure that the data is accurate and reliable. The processed data is exported to an analysis format such as CSV, Excel, etc. for subsequent analysis and evaluation.
[0041] The process of calculating the real-time deformation of the roof is as follows. In this embodiment, a small pixel size of 20 pixels and a small pixel step size of 10 pixels are used.
[0042] Step S303 - 1 , using a photometric method to combine the 2D coordinates of each small facet (observed from the left and right camera images) into a common 3D coordinate.
[0043] The basic formula for three-dimensional coordinate calculation is:
[0044] in, are the three-dimensional coordinates of the small facet, and are the 2D coordinates in the left and right camera images, respectively. and is the camera's rotation matrix.
[0045] Step S303-2, by comparing the three-dimensional coordinates of different time steps, the deformation of the roof is calculated.
[0046] The calculation formula of deformation is:
[0047] in, is the deformation amount, and are the three-dimensional coordinates of two adjacent time steps.
[0048] Step S400, performing a rollover collision test, including: Step S401, installing the vehicle on a rollover collision test bench to ensure that the vehicle is stable and meets the test standards; adjusting the parameters of the test bench, such as rollover speed, angle, etc., to simulate a real rollover accident.
[0049] Step S402: During the test, the three-dimensional multi-point optical system is activated to record the roof deformation in real time. At the same time, other key parameters such as vehicle rollover speed, acceleration, time, etc. are recorded for subsequent analysis and evaluation.
[0050] Step S403, collecting roof deformation data during the entire rolling process, including deformation amount, deformation speed, deformation direction, etc., to ensure the integrity and accuracy of the data, so as to facilitate subsequent analysis and evaluation of the safety of the vehicle structure and the effectiveness of occupant protection measures.
[0051] Step S500, performing data analysis and evaluation, includes: Step S501, data processing is performed to process and analyze the collected roof deformation data, and key parameters such as deformation amount and deformation speed are calculated. Professional software is used to visualize the data, generate deformation curves, deformation cloud maps, etc., and intuitively display the roof deformation.
[0052] Step S502: Based on the analysis results, evaluate the safety and stability of the vehicle structure in a rollover accident. Check the deformation of the roof and passenger compartment, analyze the occupant's survival space and injury risk. Evaluate the rationality of the vehicle structure design and the direction of improvement, and put forward optimization suggestions.
[0053] Step S503: According to the evaluation results, the vehicle structure is improved and designed to improve the rollover resistance. The roof structure and materials are optimized to improve the compressive strength and deformation capacity of the roof. The occupant protection measures are strengthened, such as improving the design and use of safety devices such as seat belts, airbags and air curtains.
[0054] The disclosed embodiment also provides a dynamic vehicle roof deformation measurement system based on a three-dimensional multi-point optical system, and the system uses a dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system.
[0055] 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 dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system, characterized in that: include: Install the optical system, including the bottom optical system and the top optical system, including: Install an on-board high-speed camera in the bottom optical system; set a black dot pattern on the top inner surface and surrounding parts of the A-pillar to the B-pillar on the front passenger side of the vehicle in the top optical system, and make the coverage area of the black dot pattern reach 40-50%, and the background is white; check the uniformity of black dot distribution, adjust the black dot diameter and distribution to meet the image analysis requirements; Calibration of optical systems, calibration of 3D multi-point optical systems using the ARAMIS measuring system; Process the optical system, start the on-board high-speed camera to record image data, and import the captured image data into the measurement system ARAMIS for analysis to obtain the displacement and strain of the roof surface and calculate the real-time deformation of the roof.
2. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: The vehicle-mounted high-speed camera is installed in the bottom optical system, including the following: Select two vehicle-mounted high-speed cameras, equipped with reinforced lenses and camera brackets. The lenses use wide-angle lenses, and the camera brackets are equipped with LED lights and laser sights; Fix two vehicle-mounted high-speed cameras at a preset horizontal angle and install them on the camera bracket, adjust the distance between the camera lens and the inner surface of the roof, and ensure that the camera bracket is installed firmly; Adjust the LED light and laser aimer, and use the laser aimer to focus the two vehicle-mounted high-speed cameras on the same point.
3. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 2, characterized in that: Calibration of 3D multi-point optical systems using the ARAMIS measuring system includes the following: Set the measurement volume to ensure that the roof and surrounding key components are included in the measurement range; verify the accuracy of the distance from the camera lens to the measured point and the black spot diameter, adjust the coordinate system in the ARAMIS system, and convert it to the vehicle body coordinate system.
4. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: Processing optical systems, including: Start the on-board high-speed camera and synchronously record the image data 10ms before and 1000ms after the trigger at a rate of 1000Hz; Import the captured image data into a professional measurement system for analysis to obtain the displacement and strain of the roof surface; The image data is processed using algorithms in the measurement system ARAMIS, the real-time deformation of the roof is calculated, and the processed data is exported into an analysis format.
5. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: The captured image data is imported into a professional measurement system for analysis to obtain the displacement and strain of the roof surface, including the following: The ARAMIS system identifies the surface structure of the object being measured in the camera image and compiles 2D coordinates for each pixel, combining the different 2D coordinates of the same pixel observed by the two cameras at the bottom into a common 3D coordinate for analysis; By identifying and calculating the grayscale change of a single pixel in combination with its coordinates, the displacement and strain of the structure surface are obtained.
6. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: Calculate the real-time deformation of the roof, including the following: The image data is processed using the algorithm in the ARAMIS system to calculate the real-time deformation of the roof; the algorithm takes into account the camera's lens distortion and image noise.
7. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: Calculate the real-time deformation of the roof, including the following: The 2D coordinates of each facet are combined into a common 3D coordinate using a photometric method. The basic formula for three-dimensional coordinate calculation is: in, are the three-dimensional coordinates of the small facet, and are the 2D coordinates in the left and right camera images, respectively. and is the rotation matrix of the camera.
8. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: Calculate the real-time deformation of the roof, including the following: By comparing the 3D coordinates at different time steps, the deformation of the roof is calculated. The calculation formula of deformation is: in, is the deformation amount, and are the three-dimensional coordinates of two adjacent time steps.
9. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: It also includes a rollover collision test, during which a three-dimensional multi-point optical system is activated to record the roof deformation in real time, including the following: Install the vehicle on the rollover crash test bench and adjust the test bench parameters; During the test, a three-dimensional multi-point optical system is activated to record the roof deformation in real time and other key parameters; Collect the roof deformation data during the entire rolling process, including deformation amount, deformation speed, and deformation direction.
10. The dynamic vehicle roof deformation measurement method based on a three-dimensional multi-point optical system according to claim 1, characterized in that: It also includes data analysis and evaluation, including: Process and analyze the collected roof deformation data, calculate key parameters, and perform visualization; Assess the safety and stability of the vehicle structure in a rollover accident, check the deformation of the roof and passenger compartment, and analyze the occupants' survival space and injury risks.