CN115561242A

Movatterモバイル変換

Info

Publication number: CN115561242A
Application number: CN202211168794.3A
Authority: CN
Inventors: 贺永华; 林读超; 陈守敏; 朱岩
Original assignee: GAC Motor Hangzhou Co Ltd
Current assignee: GAC Motor Hangzhou Co Ltd
Priority date: 2022-09-24
Filing date: 2022-09-24
Publication date: 2023-01-03

Abstract

Translated fromChinese

本发明涉及一种汽车车身表面缺陷的自动定位系统及其自动定位方法。适用于汽车车身涂装技术领域。本发明所采用的技术方案是：一种汽车车身表面缺陷的自动定位系统，其特征在于：具有：安装支架，安装在机械臂的端部；相机模块，安装在安装支架上，用于获取汽车车身及汽车车身表面缺陷的图像信息；激光测距模块，安装在安装支架上，用于获取安装支架与汽车车身表面的距离信息；控制终端，与机械臂、相机模块及激光测距模块通讯连接，控制终端接收相机模块获取的图像信息、激光测距模块获取的距离信息,控制终端控制机械臂的移动、相机模块与激光测距模块的启闭。

The invention relates to an automatic positioning system and an automatic positioning method for surface defects of an automobile body. It is suitable for the technical field of automobile body painting. The technical solution adopted in the present invention is: an automatic positioning system for surface defects of automobile body, which is characterized in that it has: a mounting bracket installed on the end of the mechanical arm; a camera module mounted on the mounting bracket for obtaining The image information of the car body and the surface defects of the car body; the laser ranging module, installed on the mounting bracket, used to obtain the distance information between the mounting bracket and the surface of the car body; the control terminal, communicating with the robotic arm, camera module and laser ranging module The control terminal receives the image information obtained by the camera module and the distance information obtained by the laser ranging module, and the control terminal controls the movement of the mechanical arm and the opening and closing of the camera module and the laser ranging module.

Description

Translated fromChinese

汽车车身表面缺陷的自动定位系统及其自动定位方法Automatic positioning system and automatic positioning method for surface defects of automobile body

技术领域technical field

本发明涉及一种汽车车身表面缺陷的自动定位系统及其自动定位方法。适用于汽车车身涂装技术领域。The invention relates to an automatic positioning system and an automatic positioning method for surface defects of an automobile body. It is suitable for the technical field of automobile body painting.

背景技术Background technique

汽车行业车辆生产制造涂装工序中，受涂料、涂装设备、方法及工艺的影响，车身漆面会形成各类缺陷(颗粒、流挂、橘皮、锁孔、坑包等)，现有检查工艺依靠人眼在特殊灯光环境中检查，存在漏检、错检及岗位人员过度疲劳等问题，工序品质保证能力不佳。车身表面较大，为满足生产节拍，需要减少拍照次数，因此单次拍照的视野范围要求较大。通过单摄像头获取汽车车身表面缺陷信息，由于系统在标定与计算坐标时假设车身是平面且平行的，但事实上车身表面为复杂曲面，且与像平面成不同夹角，即物距不是固定的，因此单相机定位存在不可避免的误差，无法精确检查。In the coating process of vehicle manufacturing in the automotive industry, affected by coatings, coating equipment, methods and processes, various defects (particles, sagging, orange peel, keyholes, pits, etc.) will form on the paint surface of the body. The inspection process relies on human eyes to inspect in a special lighting environment. There are problems such as missed inspections, wrong inspections, and excessive fatigue of post personnel, and the process quality assurance ability is not good. The surface of the car body is relatively large. In order to meet the production rhythm, the number of photographs needs to be reduced. Therefore, the field of view required for a single photograph is relatively large. The surface defect information of the car body is obtained through a single camera. Since the system assumes that the body is flat and parallel when calibrating and calculating coordinates, in fact the surface of the car body is a complex curved surface and forms different angles with the image plane, that is, the object distance is not fixed. , so there is an inevitable error in single-camera positioning, which cannot be checked precisely.

发明内容Contents of the invention

本发明要解决的技术问题是：为解决上述技术问题，本发明提供一种确保汽车车身物平面与相机获取的像平面平行的汽车车身表面缺陷的自动定位系统及其方法。The technical problem to be solved by the present invention is: in order to solve the above technical problems, the present invention provides an automatic positioning system and method for surface defects of a car body that ensure that the object plane of the car body is parallel to the image plane captured by the camera.

本发明所采用的技术方案是：一种汽车车身表面缺陷的自动定位系统，其特征在于：具有：The technical scheme adopted in the present invention is: an automatic positioning system for surface defects of automobile body, characterized in that: it has:

安装支架，安装在机械臂的端部；Mounting bracket, installed at the end of the mechanical arm;

相机模块，安装在安装支架上，用于获取汽车车身及汽车车身表面缺陷的图像信息；The camera module is installed on the mounting bracket, and is used to obtain image information of the car body and surface defects of the car body;

激光测距模块，安装在安装支架上，用于获取安装支架与汽车车身表面的距离信息；The laser ranging module is installed on the mounting bracket, and is used to obtain the distance information between the mounting bracket and the surface of the vehicle body;

控制终端，与机械臂、相机模块及激光测距模块通讯连接，控制终端接收相机模块获取的图像信息、激光测距模块获取的距离信息,控制终端控制机械臂的移动、相机模块与激光测距模块的启闭；The control terminal communicates with the robotic arm, the camera module and the laser ranging module. The control terminal receives the image information obtained by the camera module and the distance information obtained by the laser ranging module. The control terminal controls the movement of the robotic arm, the camera module and the laser ranging module. Opening and closing of the module;

所述相机模块具有用于获取汽车车身图像信息的第一相机和机械臂将相机模块移动至汽车车身表面缺陷位置处用于获取汽车车身表面缺陷精确图像信息的第二相机。如此，通过第一相机获取汽车车身表面上所有缺陷位置的图像信息，并且通过控制终端控制机械臂将第二相机移动至与各个缺陷对应的位置，使缺陷所在位置处汽车车身物平面与第二相机获取的像平面平行，第二相机的焦距比第一相机的焦距大，第二相机可以获取各个缺陷清晰的图像信息。The camera module has a first camera for obtaining image information of the automobile body and a second camera for obtaining accurate image information of the surface defect of the automobile body by moving the camera module to the position of the surface defect of the automobile body by a mechanical arm. In this way, the image information of all defect positions on the surface of the automobile body is obtained through the first camera, and the second camera is moved to the position corresponding to each defect by controlling the mechanical arm through the control terminal, so that the object plane of the automobile body at the position of the defect is in line with the second The image planes acquired by the cameras are parallel, the focal length of the second camera is larger than that of the first camera, and the second camera can acquire clear image information of each defect.

在所述安装支架上还安装有用于使车身表面显示清晰的视觉光源组件。如此，便于使汽车车身表面上的缺陷在光照的作用下清晰的显示在相机模块获取的图像信息内。A visual light source assembly for making the surface of the vehicle body clearly displayed is also installed on the mounting bracket. In this way, it is convenient to make the defects on the surface of the automobile body clearly displayed in the image information acquired by the camera module under the action of light.

所述激光测距模块具有三个激光测距传感器，所述激光测距传感器用于获取激光测距传感器与汽车车身表面之间的距离信息。如此，通过三个激光测距传感器获取与汽车车身表面的距离信息。当三个激光测距传感器获取的与汽车车身表面之间的距离信息相同时，可以保证第二相机获取的缺陷图像的像平面与该缺陷所在汽车车身表面位置处物平面平行，使第二相机获取的图像信息更精确。The laser ranging module has three laser ranging sensors, and the laser ranging sensors are used to obtain distance information between the laser ranging sensors and the surface of the vehicle body. In this way, the distance information to the surface of the car body is obtained through three laser ranging sensors. When the distance information obtained by the three laser ranging sensors and the surface of the automobile body is the same, it can be ensured that the image plane of the defect image obtained by the second camera is parallel to the object plane at the position of the surface of the automobile body where the defect is located, so that the second camera The acquired image information is more accurate.

作为优选，所述控制终端内设有用于存储相机模块获取图像信息的数据库。如此，将相机模块获取的图像信息保存在数据库内，便于后续对汽车车身表面缺陷消除工作的排查。Preferably, the control terminal is provided with a database for storing image information acquired by the camera module. In this way, the image information acquired by the camera module is stored in the database, which facilitates the subsequent investigation of the elimination of surface defects on the automobile body.

所述第一相机具有像素为200W、焦距为6mm的视场镜头，所述第二相机具有像素为500W、焦距为8mm的视场镜头。The first camera has a field of view lens with 200W pixels and a focal length of 6mm, and the second camera has a field of view lens with 500W pixels and a focal length of 8mm.

一种汽车车身表面缺陷的自动定位方法，其特征在于：An automatic positioning method for surface defects of an automobile body, characterized in that:

控制终端控制机械臂移动至第一相机拍摄位；The control terminal controls the mechanical arm to move to the shooting position of the first camera;

控制终端控制第一相机拍摄汽车车身表面图像，并将获取的汽车车身表面图像上传至处理器内；The control terminal controls the first camera to capture the surface image of the vehicle body, and uploads the acquired surface image of the vehicle body to the processor;

在控制终端内通过视觉算法得出汽车车身表面上缺陷的个数及各个缺陷所在的位置；The number of defects on the surface of the car body and the location of each defect are obtained through the visual algorithm in the control terminal;

由控制终端控制机械臂移动至与汽车车身表面上缺陷对应位置处；The control terminal controls the mechanical arm to move to the position corresponding to the defect on the surface of the car body;

由控制终端控制三个激光测距传感器并分别获取其与汽车车身表面之间的距离，并将获取的与汽车车身表面之间的距离信息上传至控制终端内；Control the three laser ranging sensors by the control terminal and obtain the distances between them and the surface of the car body respectively, and upload the acquired distance information to the surface of the car body to the control terminal;

控制终端内对三个激光测距传感器获取的距离信息进行分析，由控制终端控制机械臂移动，使三个激光测距传感器进行二次校准测距时获取的距离信息一致，此时第二相机与汽车车身表面上缺陷所在表面近似垂直；The distance information acquired by the three laser ranging sensors is analyzed in the control terminal, and the control terminal controls the movement of the mechanical arm so that the distance information acquired by the three laser ranging sensors during the second calibration and ranging is consistent. At this time, the second camera Approximately perpendicular to the surface where the defect is located on the surface of the automobile body;

控制终端控制激光测距传感器关闭，并控制第二相机拍摄汽车车身表面上缺陷位置处的图像并将获取的图像信息上传至处理器中。The control terminal controls the laser ranging sensor to be turned off, and controls the second camera to take images of defects on the surface of the automobile body and upload the acquired image information to the processor.

本发明的有益效果是：通过在安装在安装支架上与汽车车身表面对应面上的视觉光源组件，在视觉光源组件随机械臂移动过程中也能保持照射汽车车身表面，使汽车车身表面上的缺陷能够清晰显示在相机模块获取的图像上。第一相机获取了汽车车身表面图像并上传至控制终端内，由控制终端内的视觉算法找出汽车车身表面上的缺陷，随后由控制终端控制机械臂将第二相机依次移动到与缺陷对应的位置处；由三个激光测距传感器获取与该缺陷所在汽车车身表面的距离信息，并将该距离信息上传至控制终端内；由控制终端控制机械臂移动至三个激光测距传感器与该缺陷所在汽车车身表面的距离相同时。此时第二相机获取的缺陷所在汽车车身表面图像的像平面与缺陷所在汽车车身表面的物平面平行，提高相机模块获取图像信息的精度。The beneficial effects of the present invention are: through the visual light source assembly installed on the surface corresponding to the surface of the automobile body on the mounting bracket, the visual light source assembly can also keep irradiating the surface of the automobile body during the movement of the mechanical arm, so that the surface of the automobile body Defects can be clearly shown on the image acquired by the camera module. The first camera captures the image of the surface of the car body and uploads it to the control terminal. The visual algorithm in the control terminal finds the defects on the surface of the car body, and then the control terminal controls the mechanical arm to move the second camera to the position corresponding to the defect. position; the three laser ranging sensors obtain the distance information from the surface of the car body where the defect is located, and upload the distance information to the control terminal; the control terminal controls the mechanical arm to move to the three laser ranging sensors and the defect. When the distance from the surface of the car body is the same. At this time, the image plane of the surface image of the vehicle body where the defect is obtained by the second camera is parallel to the object plane of the surface of the vehicle body where the defect is located, so as to improve the accuracy of image information acquired by the camera module.

附图说明Description of drawings

图1：本实施例中安装在机械臂上安装支架上的结构示意图。Figure 1: Schematic diagram of the structure installed on the mounting bracket on the mechanical arm in this embodiment.

图2：本实施例中框架示意图。Figure 2: Schematic diagram of the framework in this embodiment.

图中：1、安装支架，2、第一相机，3、视觉光源组件，4、激光测距传感器，5、第二相机，6、机械臂，7、控制终端，8、数据库。In the figure: 1. Mounting bracket, 2. First camera, 3. Visual light source assembly, 4. Laser ranging sensor, 5. Second camera, 6. Robotic arm, 7. Control terminal, 8. Database.

具体实施方式detailed description

下面结合附图并通过实施例对本发明作进一步的详细说明，以下实施例是对本发明的解释而本发明并不局限于以下实施例。The present invention will be further described in detail below in conjunction with the accompanying drawings and examples. The following examples are explanations of the present invention and the present invention is not limited to the following examples.

本实施例为一种汽车车身表面缺陷的自动定位系统，具有安装了相机模块、激光测距模块的安装支架1，该安装支架1安装在机械臂6的端部上。相机模块、激光测距模块均与控制终端7通讯连接，相机模块获取的图像信息与激光测距模块获取的与汽车车身表面之间距离信息均被上传至控制终端7内。控制终端7还与机械臂6电路连接，并由控制终端7控制机械臂6移动。This embodiment is an automatic positioning system for surface defects of an automobile body, which has amounting bracket 1 installed with a camera module and a laser ranging module, and themounting bracket 1 is mounted on the end of a mechanical arm 6 . Both the camera module and the laser ranging module are connected to the control terminal 7 through communication, and the image information obtained by the camera module and the distance information obtained by the laser ranging module from the vehicle body surface are uploaded to the control terminal 7. The control terminal 7 is also electrically connected with the mechanical arm 6, and the control terminal 7 controls the movement of the mechanical arm 6.

本实施例中，在安装支架1上固定安装有视觉光源组件3，视觉光源组件3向汽车车身表面上照射光线，使汽车车身表面上的缺陷在汽车车身表面上清晰显像而使缺陷能被相机模块捕捉，使缺陷显示在相机模块获取的汽车车身表面图像上。In this embodiment, a visuallight source assembly 3 is fixedly installed on the mountingbracket 1, and the visuallight source assembly 3 irradiates light on the surface of the automobile body, so that the defects on the surface of the automobile body are clearly displayed on the surface of the automobile body and the defects can be detected. The camera module captures the defect so that it is displayed on the image of the surface of the car body that the camera module acquires.

本实施例中，在安装支架1上固定安装有第一相机2，所述第一相机2用于在开启该缺陷自动定位系统时获取该汽车车身表面的图像信息，该图像信息中含有缺陷的数量及各缺陷在汽车车身表面上的位置，所述第一相机2具有像素为200W、焦距为6mm的视场镜头。第一相机2将汽车车身表面的图像信息上传至控制终端7内，控制终端7内经过现有的视觉算法提取出汽车车身表面上缺陷的信息。本实施例中采用的视觉算法为一种基于Halcon平台的视觉算法。汽车车身表面并不是完整的平面，汽车车身表面上的缺陷并不完全处于同一平面内。为使该系统对每个缺陷均能精准定位，本实施例中，在安装支架1上还固定安装有第二相机5，所述第二相机具有像素为500W、焦距为8mm的视场镜头。第二相机5用于在通过机械臂6将安装有第二相机5的安装支架1移动至第二相机5与汽车车身表面上缺陷对应位置处精确获取每个缺陷的图像信息并上传至控制终端7内。In this embodiment, afirst camera 2 is fixedly installed on the mountingbracket 1, and thefirst camera 2 is used to obtain the image information of the surface of the automobile body when the defect automatic positioning system is turned on, and the image information contains defects. The number and the position of each defect on the surface of the automobile body, thefirst camera 2 has a field of view lens with a pixel of 200W and a focal length of 6mm. Thefirst camera 2 uploads the image information of the surface of the automobile body to the control terminal 7, and the control terminal 7 extracts the defect information on the surface of the automobile body through the existing visual algorithm. The vision algorithm adopted in this embodiment is a vision algorithm based on the Halcon platform. The surface of the car body is not a complete plane, and the defects on the surface of the car body are not all in the same plane. In order to enable the system to precisely locate each defect, in this embodiment, asecond camera 5 is fixedly installed on the mountingbracket 1, and the second camera has a field of view lens with a pixel of 500W and a focal length of 8mm. Thesecond camera 5 is used to move the mountingbracket 1 equipped with thesecond camera 5 to the corresponding position of thesecond camera 5 and the defect on the surface of the automobile body through the mechanical arm 6 to accurately acquire the image information of each defect and upload it to the control terminal within 7.

进一步的，为使第二相机5获取的图像信息内的像平面与该缺陷所在汽车车身表面上的物平面，本实施例中在安装支架1上还固定安装有三个激光测距传感器4，三个激光测距传感器4之间互相接触地安装在安装支架1上。三个激光测距传感器4发出的激光在截面上组成一个较小的三角形。三个激光测距传感器4获取安装支架1与汽车车身表面上缺陷外侧的距离信息。当三个激光测距传感器4获取的距离信息一致时，安装支架1与三个激光测距传感器4在汽车车身表面测量点形成的平面平行。因三个激光测距传感器4测量点之间的距离较近，并且第二相机5拍摄的物距短，获取图像的视场小，复杂曲面的汽车车身表面在该缺陷所在位置处的面与激光测距传感器4测量点之间形成的平面基本重合。此时第二相机5获取的缺陷所在位置处汽车车身表面图像的像平面与缺陷所在位置处汽车车身表面的物平面平行。提高了第二相机5获取的缺陷所在位置处汽车车身表面图像的精确性。Further, in order to make the image plane in the image information acquired by thesecond camera 5 and the object plane on the surface of the automobile body where the defect is located, three laserdistance measuring sensors 4 are also fixedly installed on the mountingbracket 1 in this embodiment. Twolaser ranging sensors 4 are installed on the mountingbracket 1 in contact with each other. The lasers emitted by the threelaser ranging sensors 4 form a smaller triangle on the cross section. Three laserdistance measuring sensors 4 acquire distance information between the mountingbracket 1 and the outside of the defect on the surface of the automobile body. When the distance information obtained by the three laserdistance measuring sensors 4 is consistent, the mountingbracket 1 is parallel to the plane formed by the three laserdistance measuring sensors 4 at the measurement points on the surface of the vehicle body. Because the distance between the measurement points of the threelaser ranging sensors 4 is relatively close, and the object distance taken by thesecond camera 5 is short, the field of view of the acquired image is small, and the surface of the vehicle body surface with a complex curved surface at the position of the defect is different from the The planes formed between the measurement points of the laserdistance measuring sensor 4 basically coincide. At this time, the image plane of the surface image of the vehicle body at the position of the defect acquired by thesecond camera 5 is parallel to the object plane of the surface of the vehicle body at the position of the defect. The accuracy of the surface image of the vehicle body at the location of the defect acquired by thesecond camera 5 is improved.

本实施例中，所述控制终端7内设有用于存储相机模块获取图像信息的数据库8。将相机模块获取的图像信息保存在数据库8内，便于后续对汽车车身表面缺陷消除工作的排查。In this embodiment, the control terminal 7 is provided with a database 8 for storing image information acquired by the camera module. The image information acquired by the camera module is stored in the database 8, which is convenient for the subsequent investigation of the surface defect elimination work of the automobile body.

本实施例中汽车车身表面缺陷的自动定位方法为：The automatic location method of automobile body surface defect in the present embodiment is:

控制终端7控制机械臂移动至第一相机2拍摄位；The control terminal 7 controls the mechanical arm to move to the shooting position of thefirst camera 2;

控制终端1控制第一相机2拍摄汽车车身表面图像，并将获取的汽车车身表面图像上传至处理器7内；Thecontrol terminal 1 controls thefirst camera 2 to take images of the surface of the automobile body, and uploads the acquired surface image of the automobile body to the processor 7;

在控制终端7内通过视觉算法得出汽车车身表面上缺陷的个数及各个缺陷所在的位置；In the control terminal 7, the number of defects on the surface of the automobile body and the position of each defect are obtained by a visual algorithm;

由控制终端7控制机械臂移动至与汽车车身表面上缺陷对应位置处；The control terminal 7 controls the mechanical arm to move to the position corresponding to the defect on the surface of the automobile body;

由控制终端7控制三个激光测距传感器4并分别获取其与汽车车身表面之间的距离，并将获取的与汽车车身表面之间的距离信息上传至控制终端7内；Control the threelaser ranging sensors 4 by the control terminal 7 and obtain the distances between them and the surface of the automobile body respectively, and upload the obtained distance information to the surface of the automobile body to the control terminal 7;

控制终端7内对三个激光测距传感器4获取的距离信息进行分析，由控制终端7控制机械臂移动，使三个激光测距传感器4进行二次校准测距时获取的距离信息一致，此时第二相机5与汽车车身表面上缺陷所在表面近似垂直；The distance information obtained by the threelaser ranging sensors 4 is analyzed in the control terminal 7, and the control terminal 7 controls the movement of the mechanical arm, so that the distance information obtained when the threelaser ranging sensors 4 perform secondary calibration and ranging is consistent. When thesecond camera 5 is approximately perpendicular to the surface where the defect is located on the surface of the automobile body;

由控制终端7控制激光测距传感器4关闭，并控制第二相机5拍摄汽车车身表面上缺陷位置处的图像并将获取的图像信息上传至控制终端7中。The control terminal 7 controls thelaser ranging sensor 4 to be turned off, and controls thesecond camera 5 to take images of defect positions on the surface of the automobile body and upload the acquired image information to the control terminal 7 .

本实施例的使用原理为：The usage principle of this embodiment is:

由安装在安装支架1上的视觉光源组件3向汽车车身表面打光，使汽车车身表面上的缺陷清晰表现出来。由控制终端7控制安装在安装支架1上的第一相机2获取汽车车身表面的图像，并将该图像信息上传至控制终端7内。在控制终端7内经过现有的视觉算法提取出缺陷的数量、位置等信息。由控制终端7控制机械臂6带动安装支架1移动至与各个缺陷对应的位置处。此时由控制终端7控制三个激光测距传感器4分别向缺陷外侧的汽车车身表面发射激光，三个激光测距传感器4在汽车车身表面上的测距点之间形成一个平面。激光测距传感器4获取的距离信息上传至控制终端7内，由控制终端7对获取的三个距离信息进行比对。当获取的三个距离信息不同一时，此时三个激光测距传感器4测量点所在的平面与该位置处汽车车身表面的切面不平行。由由控制终端7控制机械臂6移动，最终达到三个激光测距传感器4获取的距离信息一致，此时三个激光测距传感器4测量点所在的平面与该位置处汽车车身表面的切面平行。在控制终端7内接收的三个距离信息一致时，由控制终端7控制第二相机5获取缺陷图像，并将获取的缺陷图像信息上传至控制终端7内。因三个测量点之间的距离较小，三个测距点之间形成的平面与该缺陷所在汽车车身表面处的面基本重合。此时第二相机5获取的缺陷图像的像平面与该缺陷所在的汽车车身表面的物平面平行，第二相机5获取的缺陷图像信息更加精确。The visuallight source assembly 3 installed on the mountingbracket 1 illuminates the surface of the automobile body, so that the defects on the surface of the automobile body are clearly displayed. Thefirst camera 2 installed on the mountingbracket 1 is controlled by the control terminal 7 to obtain images of the surface of the vehicle body, and upload the image information to the control terminal 7 . In the control terminal 7, information such as the number and position of defects is extracted through the existing visual algorithm. The control terminal 7 controls the mechanical arm 6 to drive theinstallation bracket 1 to move to the position corresponding to each defect. At this time, the control terminal 7 controls the threelaser ranging sensors 4 to emit laser light to the vehicle body surface outside the defect respectively, and the threelaser ranging sensors 4 form a plane between the ranging points on the vehicle body surface. The distance information acquired by thelaser ranging sensor 4 is uploaded to the control terminal 7, and the control terminal 7 compares the three acquired distance information. When the three acquired distance information are not the same, the plane where the measurement points of the threelaser ranging sensors 4 are located is not parallel to the tangent plane of the vehicle body surface at this position. The movement of the mechanical arm 6 is controlled by the control terminal 7, and finally the distance information acquired by the threelaser ranging sensors 4 is consistent. At this time, the plane where the measurement points of the threelaser ranging sensors 4 are located is parallel to the tangent plane of the vehicle body surface at this position . When the three distance information received in the control terminal 7 are consistent, the control terminal 7 controls thesecond camera 5 to acquire defect images, and uploads the obtained defect image information to the control terminal 7 . Because the distances between the three measuring points are small, the plane formed between the three ranging points basically coincides with the surface of the vehicle body where the defect is located. At this time, the image plane of the defect image acquired by thesecond camera 5 is parallel to the object plane of the vehicle body surface where the defect is located, and the defect image information acquired by thesecond camera 5 is more accurate.

以上所述，仅为本发明较佳的具体实施方式，但本发明的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本发明揭露的技术范围内，根据本发明的技术方案及其发明构思加以等同替换或改变，都应涵盖在本发明的保护范围之内。The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.