Research On Automatic And Complete 3D Reconstrction Based On Multinode Sensing And Speckle Projection

Automatic and rapid acquisition of complete 3D data of object and on-line 3D measurement based on fringe projection has been a hot topic in recent years.The relative technologies have advantages of noncontact,high speed,and have been widely used in many fields such as industry manufacture,heritage conservation,body scanning and medical diagnosis etc.There are three key issues have to be solved in complete and rapid 3D data acquisition: high efficient system suitable structure for automatic measurement and the calibration of the system;rapid 3D reconstruction in single view and automatic,efficient 3D data registration to obtain complete 3D model.And also the low-cost,miniaturized,integrable system has becoming a critical requirement for expanding application of 3D measurement technology in many fields.In this paper,the method and system for automatic and rapid complete 3D measurement was studied and low-cost,miniaturized system was introduced.Furthermore,the reasonable metrological calibration is critical to guarantee the accuracy and right use of the 3D measurement system.So the metrological calibration methods for different systems were also researched.The main contents and contributions including:A rapid speckle projection 3D reconstruction method based on fast corresponding points searching algorithm was proposed for rapid 3D data acquisition in complete 3D measuring system.By optimize the algorithm of projection rectification and sub-pixel matching in the digital correlation,the efficiency and accuracy of point searching was greatly promoted.Experiment results demonstrated that the corresponding points searching time reduced from 8 seconds to 3.2 seconds,and the searching error in the edge area with distortion was effectively decreased.The computing time of speckle 3D reconstruction was largely decreased.Then,fast and accurate 3D data acquisition can be realized.In order to measure the complete 3D data of object automatically in real scenes,an automatic and rapid complete 3D measurement method and system using multi-node 3D sensors base on speckle and fringe projection was developed.A flexible automatic measuring system was designed,and calibration method for sensors without field of view overlap was given.The speckle projection 3D reconstruction method based on rapid corresponding point searching algorithm was used to promote the efficiency 3D data acquisition in single view.And an automatic range data registration strategy using two aided-cameras was invented.Experiment results shows that the presented method can realize automatic complete 3D data measurement with high efficiency and accuracy.Otherwise,the 3D sensor nodes of system can decrease or increase flexibly,which can be used to solve different measurement tasks in real scenes.A low cost and small size 3D measuring system based on laser speckle projection was presented.By using semiconductor laser as light source,a low cost and miniaturized speckle pattern projector was established using frosted glass and diffractive optics respectively.The experiment results show that the presented system can realize rapid 3D data acquisition with certain accuracy,while the cost and size of the system was sharply reduced.Meanwhile,a culling algorithm based on connected region has been introduced to erase the error data in the edge area.The validity of the algorithm has been verified by experiment results.The quality of 3D data obtained using speckle projection method can be promoted greatly by discard only little error data.The metrological performance and metrological calibration method for complete 3D measuring system based on fringe projection was researched.According to the precision verification requirements of the system applied in dimension measurement and position measurement,a metrological calibration method was developed and the relative standards were given out in this paper.The measurement uncertainty of the system used in different tasks were analyzed,and the evaluation procedure and results of measurement uncertainty was given,which can provide a powerful reference for precise measurement using the 3D scanning system based on fringe projection.