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单摄像机虚拟立体视觉测量技术研究 总被引:6,自引:0,他引:6
以双目立体视觉传感器三维测量模型为基础,提出了一种用于测量空间三维点坐标的低成本单摄像机模型。该模型利用光学成像,把单摄像机镜像为一对虚拟摄像机,在一个CCD像面上采集到同一物体存在视差的两幅图像,从而恢复空间点的三维信息。讨论了单摄像机传感器测量空间三维点坐标的基本原理,建立了单摄像机传感器的测量模型,克服了双摄像机系统中成本高、切换采集左右摄像机的图像使检测速度减慢等诸多缺陷,为空间三维点的精密测量提供了经济、快速、有效的测量途径。实验表明.传感器可实现约0.8%的相对测量精度.证明了本方案合理、有效。 相似文献
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多自由度双目立体视觉系统可以解决传统双目立体视觉视场区域小的问题。避免双目摄像机每转动一个角度都需要重新标定外参数,提出了一种基于转轴参数的标定方法。只需标定出初始位置时双目摄像机的内外参数,使摄像机绕转轴旋转,根据单应性原理测量摄像机与标定模板的位姿关系,确定转轴方向矢量与轴上点坐标。最终利用Rodrigues旋转矩阵确定旋转已知角度后双目摄像机的外参数,实现多自由度双目系统的标定。实验结果表明,提出的方法能准确测量转轴参数,完成多自由度双目立体视觉系统的快速标定,提高系统的工作效率。 相似文献
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为了建立物体的整体三维模型,在一般线结构光三维视觉系统结构的基础上,提出了一种三维视觉扫描方式———被动模式。这种模式是基于摄像机不动,使物体旋转,实现对物体的全方位扫描,解决了物体三维模型周视扫描的问题。给出了物体旋转轴心坐标的标定方法和物体的三维重建过程。 相似文献
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相机标定技术是结构光三维视觉测量的关键技术之一,结构光系统的相机标定的精度对三维测量的精度有很大影响。首先对三线结构光系统图的相机标定方法进行了分析,简单介绍了工业相机成像的几何模型及标定的原理;其次利用Harris角点检测方法提取特征点坐标,并选用了BP神经网络来校正工业相机的畸变模型,以提高标定算法的优化速度和标定精度;最后采用张正友的平面标定法对校正后的摄像机模型进行标定实验,由实验结果知,该方法具有一定的准确性和有效性,在一定误差范围内,基于神经网络畸变校正的张正友相机标定能够有效提高视觉检测的精度。 相似文献
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目前大气透射仪存在发射端和接收端安装调校困难的问题,并且在工作过程中,发射端和接收端一旦发生偏移,光轴不处于一条直线,将大大影响能见度测量结果。针对这些问题,提出将近景摄影测量技术应用到大气透射仪的对准系统中,采用圆形作为人工标志物,通过图像处理及椭圆最小二乘拟合算法,计算人工标志物的圆心坐标,根据标志物的圆心坐标与摄像机镜头的中心坐标的位置关系,将发射端和接收端的摄像机镜头的中心通过旋转结构拉倒图像中心;由于摄像机与光轴是同轴设计,所以摄像机镜头对准就是实现了光轴的对准。实验证明,利用近景摄影测量技术能够实现大气透射仪快速准确对准,并且能够实时监控保证光轴始终保持一条直线。 相似文献
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Ugeda MM Fernández-Torre D Brihuega I Pou P Martínez-Galera AJ Pérez R Gómez-Rodríguez JM 《Physical review letters》2011,107(11):116803
Understanding the coupling of graphene with its local environment is critical to be able to integrate it in tomorrow's electronic devices. Here we show how the presence of a metallic substrate affects the properties of an atomically tailored graphene layer. We have deliberately introduced single carbon vacancies on a graphene monolayer grown on a Pt(111) surface and investigated its impact in the electronic, structural, and magnetic properties of the graphene layer. Our low temperature scanning tunneling microscopy studies, complemented by density functional theory, show the existence of a broad electronic resonance above the Fermi energy associated with the vacancies. Vacancy sites become reactive leading to an increase of the coupling between the graphene layer and the metal substrate at these points; this gives rise to a rapid decay of the localized state and the quenching of the magnetic moment associated with carbon vacancies in freestanding graphene layers. 相似文献
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A. H. Taub 《General Relativity and Gravitation》1979,10(12):1009-1009
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In this note we use some of the results of [3] to derive a general duality theorem for the cohomologies of foliated structures on a manifold. The result is applied to the special case of a symplectic manifold M on which the foliation is given by a complex polarization F in the sense of geometric quantization. We obtain, for example, a rigorous proof of the fact that for a smooth function ƒ on M whose Hamiltonian vector field leaves F invariant, the spectrum of the corresponding prequantization operator v(ƒ) coincides with the spectrum of its transpose, under the above duality. This latter result was obtained by Simms in [12] under certain hypotheses. Proofs of the validity of those hypotheses are now available in the literature; cf. [3] and [7]. 相似文献
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Valfells A. Verboncoeur J.P. Lau Y.Y. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2000,28(3):529-536
Analyzes the effects of space charge shielding on the steady state of a multipactor discharge on a dielectric. Analytic methods are used to obtain an exact function for the potential in the discharge, assuming a Maxwellian distribution of emitted electrons. An equation for the amount of power deposited on the dielectric by the multipactoring electrons, for a given saturation level, is given. A simple method for obtaining the saturation level, for a given material, is obtained 相似文献
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We study the relation between the centro-affine geometry of star-shaped planar curves and the projective geometry of parametrized maps into RP1. We show that projectivization induces a map between differential invariants and a bi-Poisson map between Hamiltonian structures. We also show that a Hamiltonian evolution equation for closed star-shaped planar curves, discovered by Pinkall, has the Schwarzian KdV equation as its projectivization. (For both flows, the curvature evolves by the KdV equation.) Using algebro-geometric methods and the relation of group-based moving frames to AKNS-type representations, we construct examples of closed solutions of Pinkall’s flow associated with periodic finite-gap KdV potentials. 相似文献