CN-122023542-A - Unfixed binocular stereoscopic vision device and calibration method

CN122023542ACN 122023542 ACN122023542 ACN 122023542ACN-122023542-A

Abstract

The invention provides a non-fixed binocular stereoscopic vision device and a calibration method, a non-fixed binocular stereoscopic vision system comprises a left-eye main camera, a right-eye main camera, an auxiliary binocular camera, a pose target and an image processing device. The left-eye main camera, the auxiliary binocular camera and the image processing device are fixed on a rigid body structure, and the optical axis direction of the left-eye main camera is perpendicular to the optical axis direction of the auxiliary binocular camera. The right eye main camera and the pose target are fixed on another rigid body structure, and the optical axis direction of the right eye main camera is perpendicular to the normal direction of the pose target plane. When the non-fixed binocular stereoscopic vision system works, the optical axes of the two main cameras face the same direction, and the binocular cameras are assisted to observe the pose targets. After the calibration by the method provided by the invention, the relative pose relation of the left and right main cameras can be calculated on line in real time by assisting the binocular cameras to observe the pose targets, so that the non-fixed binocular stereoscopic vision system can complete stereoscopic vision tasks such as three-dimensional measurement and the like.

Inventors

GU YUZHANG
WANG DAHE

Assignees

浙江大学嘉兴研究院

Dates

Publication Date: 20260512
Application Date: 20260129

Claims (8)

1. A non-stationary binocular stereoscopic vision device, comprising: The main control computer is used for collecting images shot by the non-fixed binocular stereoscopic vision device; the left eye module is used for integrating a left eye main camera, assisting a binocular camera and an image processing module; The right eye module is used for integrating a right eye main camera and a pose target; The left-eye main camera is used for shooting left-eye images in the non-fixed binocular stereoscopic vision device; the right-eye main camera is used for shooting right-eye images in the non-fixed binocular stereoscopic vision device; The auxiliary binocular camera is used for shooting a pose target on the right-eye module; The image processing module is used for acquiring an image of the pose target on the right-eye module through the auxiliary binocular camera, calculating the relative pose relation between the auxiliary binocular camera and the pose target, and further calculating the relative pose relation between the left-eye main camera and the right-eye main camera; the pose target is used for providing pose information of the right eye module; The main control computer is respectively connected with the left-eye main camera, the auxiliary binocular camera, the image processing module and the right-eye main camera through data lines, the left-eye main camera and the auxiliary binocular camera are fixed on one rigid body structure, the optical axis directions of the left-eye main camera and the auxiliary binocular camera are mutually perpendicular, the right-eye main camera and the pose target are fixed on the other rigid body structure, the optical axis direction of the right-eye main camera is perpendicular to the normal direction of the pose target, and the image processing module, the left-eye main camera and the auxiliary binocular camera are fixed on the same rigid body structure.
2. The non-stationary binocular stereoscopic vision device of claim 1, wherein there is no rigid connection between the left and right eye modules.
3. The non-stationary binocular stereoscopic vision device of claim 1, wherein both of the auxiliary binocular cameras can capture a complete image of the pose target when the optical axes of the left and right eye primary cameras are directed to the same observation object or region.
4. A method for calibrating a non-stationary binocular stereoscopic vision device, characterized in that it is realized on the basis of a non-stationary binocular stereoscopic vision device according to any one of claims 1 to 3, further comprising the following components: The turntable is used for carrying the left eye module to rotate when the pose relation between the left eye main camera and the auxiliary binocular camera is calibrated, and carrying the right eye module to rotate when the pose relation between the right eye main camera and the pose target is calibrated; The calibration plate is used for providing three-dimensional coordinates of the characteristic points when the pose relation between the left-eye main camera and the auxiliary binocular camera is calibrated, and providing three-dimensional coordinates of the characteristic points when the pose relation between the right-eye main camera and the pose target is calibrated; The binocular camera for calibrating is used for calibrating the pose relation between the right-eye main camera and the pose target; The calibration step specifically comprises the following steps: S1, calibrating a left-eye main camera, namely calibrating internal parameters and distortion coefficients of the left-eye main camera by a Zhang Zhengyou checkerboard calibration method; S2, calibrating the right-eye main camera, namely calibrating internal parameters and distortion coefficients of the right-eye main camera by a Zhang Zhengyou checkerboard calibration method; S3, calibrating the auxiliary binocular camera, namely calibrating internal parameters, external parameters and distortion coefficients of the auxiliary binocular camera by using a Zhang Zhengyou checkerboard calibration method; s4, calibrating the binocular camera for calibration, namely calibrating internal parameters, external parameters and distortion coefficients of the binocular camera for calibration by a Zhang Zhengyou checkerboard calibration method; S5, calibrating the pose relation between the left-eye main camera and the auxiliary binocular camera, namely fixing the left-eye module on the rotary table, fixing the calibration plate in front of the left-eye main camera at the moment, rotating the rotary table to stay at a plurality of positions, shooting the calibration plate by the left-eye main camera at the stay positions, calculating the pose relation between the left-eye main camera and the calibration plate by using the calibration result of the left-eye main camera obtained in the step S1, continuing rotating the rotary table until the auxiliary binocular camera can shoot the position of the calibration plate, calculating the pose relation between the auxiliary binocular camera and the calibration plate by using the calibration result of the auxiliary binocular camera obtained in the step S3, wherein the left-eye main camera cannot observe the calibration plate, calculating the pose relation between the left-eye main camera and the calibration plate at the stay positions of the previous rotary table through the pose relation between the left-eye main camera and the calibration plate, further calculating the pose relation between the left-eye main camera and the auxiliary binocular camera, and storing the pose relation in the image processing module; The right eye module is fixed on the rotary table, the calibration plate is fixed in front of the right eye main camera at the moment, the calibration purpose binocular camera is fixed behind the right eye main camera at the moment, the field of view covers the calibration plate, the rotary table stays at a plurality of positions, the right eye main camera shoots the calibration plate at the stay positions, the position relation between the right eye main camera and the calibration plate is calculated by using the calibration result of the right eye main camera obtained in the step S2, the rotary table is continuously rotated to the position where the auxiliary binocular camera can shoot the position relation, the position relation between the position relation and the calibration plate is calculated by using the calibration result of the calibration purpose binocular camera obtained in the step S4, the position relation between the right eye main camera and the calibration plate at the current rotary table position can be calculated by using the position relation between the right eye main camera and the calibration plate at the previous rotary table position, and the position relation between the right eye main camera and the position of the calibration plate can be calculated, and the position relation between the right eye main camera and the position relation between the position of the right eye main camera and the position of the calibration plate can be stored in the module; And S7, calculating the pose relation between the left-eye main camera and the right-eye main camera, namely, observing the pose target through the auxiliary binocular camera, calculating the pose relation between the auxiliary binocular camera and the pose target through the image processing module, and then calculating the pose relation between the left-eye main camera and the auxiliary binocular camera obtained in the step S5 and the pose relation between the right-eye main camera and the pose target obtained in the step S6 through the pose relation between the left-eye main camera and the right-eye main camera.
5. The method of calibrating a non-stationary binocular stereoscopic vision device according to claim 4, wherein the turntable can precisely feed back the rotation angle.
6. The method of claim 4, wherein the calibration plate is a calibration plate with a mark such as charuco calibration plate or aruco calibration plate, and the calibration plate still provides feature point coordinate information for calibration in case of partial shielding.
7. The method for calibrating the non-stationary binocular stereoscopic vision device according to claim 4, wherein in the step S5, the pose relationship between the left-eye main camera and the calibration plate at the previous turntable resting position is calculated, specifically, the calculated pose relationship between the left-eye main camera at the turntable resting position and the calibration plate can be calculated by converting the calculated pose of the left-eye main camera at the turntable resting position into the coordinate system of the calibration plate, wherein the optical center position forms a plane perpendicular to the turntable rotation axis and the optical center position forms a circular track centered on the intersection point of the plane and the turntable rotation axis, and the pose relationship between the left-eye main camera at any turntable resting position and the calibration plate can be calculated by fitting the circle.
8. The method for calibrating the non-stationary binocular stereoscopic vision device according to claim 4, wherein in the step S6, the pose relationship between the right-eye main camera and the calibration plate at the previous turntable resting positions is calculated, specifically, the pose relationship between the right-eye main camera and the calibration plate at any turntable resting position can be calculated by converting the calculated pose of the right-eye main camera at the turntable resting positions into the coordinate system of the calibration plate, wherein the optical center position forms a plane perpendicular to the turntable rotation axis and the optical center position forms a circular track centered on the intersection point of the plane and the turntable rotation axis, and the pose relationship between the right-eye main camera and the calibration plate at any turntable resting position can be calculated by fitting the circle.

Description

Unfixed binocular stereoscopic vision device and calibration method Technical Field The invention relates to the field of binocular stereo vision, in particular to a non-fixed binocular stereo vision device and a calibration method. Background The conventional binocular stereo vision apparatus generally refers to a fixed binocular stereo vision apparatus in which the relative pose relationship between two binocular cameras is fixed. After the internal parameters of the two cameras and the external parameters representing the pose relationship between the two cameras are obtained through calibration, binocular stereo measurement, three-dimensional scene reconstruction and other stereo vision tasks can be performed through binocular stereo vision image processing. Starting from the structure and principle of the fixed binocular stereoscopic vision device, it can be found that once the relative pose of the two cameras is fixed, the range of the binocular common field of view is fixed. The binocular stereo vision measurement principle shows that the three-dimensional measurement accuracy is inversely related to the base line distance. The baseline distance of the existing fixed binocular stereo vision device is usually short and is generally not more than 200 mm, and the high-precision three-dimensional measurement distance is generally not more than 15 m. To increase the high-precision three-dimensional measurement distance of binocular stereoscopic vision to the level of hundred meters, the baseline distance of the binocular stereoscopic vision needs to reach the level of meters, and the focal length of the lens of the binocular camera is longer. Such long baseline fixed binocular stereoscopic vision devices lose portability due to the size being too large. In addition, the binocular common view field of the fixed binocular stereoscopic vision device cannot be adjusted according to the requirement, and flexible adjustment of the binocular common view field is particularly important for the application that the measurement target is a dynamic target. The existing binocular stereoscopic vision device and the calibration technology thereof have the following technical problems: Fixing the relative pose relation between the two eyes, calibrating once in advance after fixing, and using the parameters calibrated in advance in the later measurement; Once the relative pose relationship between the two eyes is changed, the two eyes need to be recalibrated, and the existing calibration method generally adopts a checkerboard calibration method, namely, the two eyes shoot images of a set of checkerboard calibration plates with known physical size parameters, and then calibration is carried out based on a Zhang's checkerboard calibration method (Zhang Zhengyou published paper ' A Flexible New Technique for Camera Calibration ') in 1998), so that the whole calibration process is tedious and time-consuming, and the requirement of adjusting the binocular common view field aiming at a dynamic target in real time cannot be met. Disclosure of Invention In order to solve the problem that the relative pose relationship between the two eyes needs to be calibrated again once the relative pose relationship between the two eyes is changed in the existing binocular stereo vision technology, the invention provides the non-fixed binocular stereo vision device and the calibration method. The invention is realized by the following technical scheme: The invention discloses a non-fixed binocular stereoscopic vision device, comprising: The main control computer is used for collecting images shot by the non-fixed binocular stereoscopic vision device; the left eye module is used for integrating a left eye main camera, assisting a binocular camera and an image processing module; The right eye module is used for integrating a right eye main camera and a pose target; The left-eye main camera is used for shooting left-eye images in the non-fixed binocular stereoscopic vision device; the right-eye main camera is used for shooting right-eye images in the non-fixed binocular stereoscopic vision device; The auxiliary binocular camera is used for shooting a pose target on the right-eye module; The image processing module is used for acquiring an image of the pose target on the right-eye module through the auxiliary binocular camera, calculating the relative pose relation between the auxiliary binocular camera and the pose target, and further calculating the relative pose relation between the left-eye main camera and the right-eye main camera; the pose target is used for providing pose information of the right eye module; The main control computer is respectively connected with the left-eye main camera, the auxiliary binocular camera, the image processing module and the right-eye main camera through data lines, the left-eye main camera and the auxiliary binocular camera are fixed on one rigid body structure, the optical axis directions of the left-eye m