Proc. SPIE. 7659, 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing
KEYWORDS: Statistical analysis, 3D acquisition, 3D image reconstruction, Data modeling, 3D modeling, Image registration, Data acquisition, 3D image processing, Range image registration, Structured light
3D data registration algorithm based on invariant was proposed, which is sparse range image from stripe coded
structured light system. The range image is uneven and its corresponding points during different views are not the same
ones, but the adjacent regions. The algorithm is improved iterative closed points algorithm; invariant is added during
search corresponding points such as the volume of tetrahedron. The impact of volume on noise, rigid translation, and
perturbation are analyzed by means of statistics experiments, and then the search criterions are proposed. Experiments
verified the validity of the data registration algorithm from the quantitative and qualitative aspects.
The principle of spatial periodicity used for coding is proposed in the paper, the maximum stripe deformation (due to
depth change on surface) and measuring resolution limit is analyzed. When spatial periodicity is used for coding, the
resolution is greatly improved, or the number of pattern is greatly reduced for real-time structured light systems. When
spatial periodicity is exploited in coding design, the number of coding is limited according to the principle of spatial
periodicity, which is the maximum of measuring resolution is determined. Or when spatial periodicity is used in coding
design, bottom limit of patterns is defined, which is maximum response speed in real-time structured light system. A
novel coded pattern based on spatial periodicity for real-time structured light system is presented. These coding patterns
allow range scanning of moving objects with high measurement resolution.
Based on an analysis of maximum stripe deformation (due to depth change on surfaces) and measuring resolution limits, a principle of spatial periodicity used for coding is proposed. When spatial periodicity is used for coding, the resolution is greatly improved, or the number of patterns is greatly reduced for real-time structured light systems. A novel coded pattern for real-time structured light systems is presented, which is based on spatial periodicity. The coding pattern allows range scanning of moving objects with easy implementation of decoding and high measurement resolution. Using alternate time-space coding in a structured light system, we achieve a measurement speed of 20 frames per second with two stripe patterns.
According to Sampling Theorem and image processing, structured light system has some limits, such as the
measurement resolution is restricted, some little gaps can not be measured and there are some errors or lost data on the
border of surface. A novel rotatable interlaced coding in real-time system of 3D information acquisition using structuredlight
imaging is proposed. It is consisting of two free directions of three-frame space-time light pattern, which can
acquire the denser 3D data from a single viewpoint. It can decrease the error from range image registration and advance
the system accuracy. The paper builds a real-time system of 3D profile measurement using structured-light. It allows a
hand-held object to rotate freely in the space-time coded light field, which is projected by the projector.
The three-dimensional shape measurement has been widely used in a lot of applications such as traffic, entertainment, architecture design, manufacturing and archeology. The paper simplifies the principle of structured-light triangulation with the constraints of light-plane and takes the radial lens distortion during CCD imaging into account, which is able to improve the system accuracy. In order to release the limit of spatial and temporal stereo in the structured light system and improve the process rate and accuracy, the system utilizes the space-time stripe boundary coded patterns. ICP (Iterative Closest Points) is widely used for geometric alignment of three-dimensional models when an initial estimate of the relative pose is given, or the relative motion is small. According to the features of data from structured light acquisition system, the paper utilizes the advanced matching algorithm, which is based on projection. This algorithm is easer and more accurate than conventional ICP.