Reserch On Simple And Fast Calibration Of The3D Imaging System Based On Phase Measurement

Phase-calculation-based fringe projection techniques are active research fields in academiaand industry because of the advantages of non-contact operation, full-field acquisition, highaccuracy and fast data processing.An important step is calibration of the phase-based3D imaging system, which converts theabsolute phase map into3D shape data. Existing calibration methods are complicated and hard tocarry out because of using a translation stage or gauge block and limited in laboratoryenvironment. In the process of the acquisition of deformed fringe patterns, delay time needs toset artificially to complete the matching of projection and acquisition.Therefore, the main content of this thesis is determined in order to solve above problems:the hardware structure of3D imaging system and the experimental platform is designed, andaccording to the calibrated intrinsic and extrinsic parameters of CCD camera, a complete andautomatic calibration method of the3D imaging system is given, including depth calibration andtransverse calibration. Furthermore, the program function module used to calibrate3D imagingsystem completely and automatically is designed and developed through Matlab developmentplatform. A key complete and automatic calibration of the whole3D imaging system is realizedto make the operation simple and flexible in the calibration process by using the acquisition ofimage information. The hardware structure of fast acquisition system and the experimentalplatform is designed, and the synchronization between acquisition and projection ofthree-dimensional code data and design of processing algorithm is completed based on theoverall frame and structure of3D imaging system software package designed and developed byresearch group, and the corresponding software system is developed by the author of this paperto make the acquisition time be saved and acquisition rate be raised.After calibrating the3D imaging system by using the proposed calibration method and the designed calibration software, the paper evaluates the calibrated system qualitatively andquantificationally. The result shows the proposed calibration method can calibrate the3Dimaging system based on phase calculation availably and reliably. The designed calibrationsoftware can make the calibration process simple and fast. Through the designed rapidacquisition function module to make the matching between the projector projection and cameraacquisition of the fast acquisition system be realized, and the3D imaging system is used tocomplete the shape measurement of3D dynamic object. The result shows the fast acquisitionsystem can obtain3D shape information of dynamic object surface.