Study Of Key Techniques On Mapping Camera Calibration Turntable Structure System

Test tables have respective characteristics according to different using demands. Calibrating mapping camera bears new requirements for turntable which include large scale, low vertical axis, great loading capacity, high positioning accuracy and stability.This dissertation researches the key techniques of mapping camera calibration turntable structure system design based on practical engineering project.Firstly, the turntable scheme about structure design, driving method, angles measuring and electronic controlling are analyzed and researched. Secondly, an intensive study of the mechanical structure is made and it includes low and high rigidity structure; light and high rigidity structure; high accuracy and high stability dense ball bearing shafting; high resolution and high stability angular micro driving device. Thirdly, the author tests errors of the table. Finally,the author studies positioning error of the turntable based on multi-body system theory, deduces the formula in error positioning and uses it to analyze the influence degree of all errors.In this dissertation, based on the method of integrating theory with engineering practice the table is intensively studied from the following aspects: specific structure design, error analysis and accuracy testing. Theoretical research of the dissertation includes roughness combined with precision driving scheme, micro displacement technique, accuracy testing method , multi-body system theory and positioning error. Engineering practice includes big structure member design, shafting structure design and angular micro driving device design.In this dissertation, centering on the turntable's characteristics of the large scale, great load, high accuracy and high stability, the author studies and analyzes turntable in an aspect of structure and precision . The author advances the idea of roughness combined with precision to solve the conflict of big angle and high precision, that is double driving scheme of torque motor coarse positioning and angular micro driving device accurate positioning ; the author puts forward a new angular displacement conversion principle which can make straight-line displacement into angular displacement ,and designs angular micro driving device by the principle. The table can acquire high positioning accuracy in a small angle range satisfying operating requirements in use of the device. The author introduces multi-body system theory, by which we can analyze the various errors'influence on the positioning error . Matlab is used to simulate and analyze the influence. By means of graphics we visually can see the influence of various errors so that reasonable distribution of errors can be achieved in overall design. Mostly error data can be gotten through pre-computation algorithm and be analyzed and corrected in the practical work of turntableThe study of this dissertation provides theoretical basis and practical experience for the research of large-scale high accuracy turntable,which is prominent in theoretical and practical significance.