Research On 3d Measurement Method Of Space Vision Servo Structured Light

With the rapid development of three-dimensional measurement technology,the traditional contact measurement method has been difficult to meet the needs of industrial detection,more and more non-contact measurement methods have been widely used.Structured light 3D measurement method has become one of the research focuses of researchers in 3D measurement at home and abroad because of its advantages of non-contact,high measurement accuracy,good real-time,etc.It is also widely used in industrial inspection,reverse engineering,cultural relic restoration,visual servo and other fields.In the development of structured light measurement technology,there are also many problems to be solved,including image noise,information loss,calibration accuracy to be optimized,etc.Therefore,it is of theoretical and practical significance to carry out research on structured light 3D measurement methods.Aiming at the problems existing in the 3D measurement method of structured light,starting from the principle of spatial structured light measurement and system design,the key technologies such as calibration of the measurement system,extraction of the center of structured light fringes,etc.are emphatically studied.The main research contents are as follows:Firstly,the basic principle of the linear structured light 3D measurement system is studied,and the direct triangulation method is compared with the oblique triangulation method.On the basis of the establishment and mutual transformation of the four major coordinate systems,the linear model and nonlinear model in the camera imaging model are deduced respectively,and the visual measurement model of t he measurement system is further studied.After the structural design of the measurement system is completed,the visual measurement system studied in this paper is selected according to the experimental requirements and practical conditions.Secondly,the camera calibration,structured light plane calibration and mobile platform pose calibration are mainly studied.According to the requirements of this experiment,Zhang Zhengyou calibration method is selected to calibrate the camera,and the derivation of this calibration method is completed and the calibration experiment is carried out;Then choose the light plane calibration method based on the plane target to calibrate the light plane.After extracting the center information of multiple structured light stripes and splicing them into the camera coordinate system,the equation of the light plane is obtained by fitting;For the calibration of the moving position and pose of the mobile platform,the moving direction of the mobile platform can be obtained by analyzing and calculating the moving direction of the fixed point on the calibration target.Finally,the algorithm of extracting the stripe center of line structured light and the method of 3d measurement of line structured light are studied.Based on the traditional light strip center extraction algorithm,this paper proposes a structured light center extraction method based on K-means clustering.The experimental results and analysis verify that the comprehensive performance of this algorithm is good.For the measurement of standard workpiece,the 3D space information of its surface is obtained and its height information is calculated.The experimental results show that the linear structured light 3D measurement system built in this paper can complete the rapid and accurate measurement of standard workpiece.