| With the development of the times, the three-dimensional measurement has a wide ranging and important significance of the application in the fields of robot vision, bio-engineering, virtual reality, industrial testing as well as defense aerospace. The purpose of this thesis is to establish a non-contact measurement system which can measure geometrical parameters of objects.According to the characteristics of non-contact measurement, and with the use of binocular stereo vision technology, a set of non-contact measurement system is designed and implemented.The application of binocular stereo vision in non-contact three-dimensional parameters measurement methods is researched deeply from both theory and practice. The major work is as follows:(1) Binocular stereo vision system is put forward and making two cameras as a basic measurement unit, using 3-D binocular vision to restore the three-dimensional coordinates of the principle features of the points.The system structure and the specific methods of measurement are introduced.(2) The traditional algorithms of camera calibration are analyzed and compared, considering lens radial distortion and tangential distortion of the camera imaging model, with the combination of linear and nonlinear optimization method the parameters of the system cameras can be obtained.(3) Feature extraction algorithms for non-contact measurement are studied, and in order to improve the accuracy of corner target location, an algorithm is proposed.(4) A cross correlation criterion of images based on features, gray scale and gradient is proposed, and a stereo matching algorithm is designed according to several constraints.(5) Sorts of the experiments for binocular stereo vision are analyzed detailed, including the accuracy comparison of 5 kinds of 3D point reconstruction algorithms.The system is designed and implemented by VC + +6.0, and the experimental results show that the use of the feature extraction and matching algorithms proposed in this paper has a high precision of measurement and certain practical value. |
