Research On Multiple Degrees Of Freedom Binocular Stereo Vision System

Aiming at the shortcomings of the traditional binocular stereo system,based on the extensive understanding of the domestic and foreign literatures,the multiple degrees of freedom(multi-DOF)binocular stereo vision platform is built.The influence of structural parameters of multi-DOF binocular stereo vision system on the measurement accuracy is analyzed.The method of multi-field point clouds automatic registration is researched and analyzed,which provides a reference for object reconstruction of large scene.The work is composed of the following aspects:(1)The calibration principle of internal and external parameters of binocular stereo vision system is introduced,and two methods of 3D reconstruction are introduced in detail.The least squares method is used to calculate the 3D coordinates of the target point by using homography transformation;3D reconstruction is achieved by the method of disparity which uses stereo rectification,image matching,reprojection and other operations.(2)Based on the traditional binocular stereo vision,we study the multi-DOF binocular stereo vision system.The scene is divided into a number of sub-areas for reconstruction respectively and the whole registration is achieved finally.Aiming at the problem of multiple calibration of multi-DOF system,we study an calibration method based on the shaft parameters.The external parameters of the system are calculated by using the parameters of the shaft and the rotation angle.(3)The influence of structural parameters on the measurement accuracy of multiDOF binocular stereo vision system is analyzed.The influence of the parameters such as the angle of the field,the length of the baseline,the angle between the optical axis and the baseline,the focal length and the object distance on the measurement error of the system is analyzed according to the structural model and design experimental verification.Finally the flow of multi-DOF binocular stereo vision system is designed.(4)According to the parameters analysis results,the multi-DOF binocular stereo vision system is constructed.The sub-regions of the measurement target are reconstructed by least squares method or parallax method,and the multiple sub-regional target point clouds are converted to the same world coordinate system and the large field of view 3D reconstruction is achieved finally.The experimental results show that the system measurement error is less than 3%,which satisfies the requirements of the preliminary registration of the point clouds.The multi-DOF binocular stereo vision system based on rotating axis parameters can achieve large field 3D reconstruction.