球面仿生复眼的标定与定位研究

发布时间：2018-04-30 12:40

本文选题：仿生复眼 + 目标定位　；参考：《中国科学技术大学》2017年硕士论文

【摘要】：视觉定位作为三维测量技术的一种重要手段,已广泛应用在工业检测、医学诊疗、影视特效和安防监控等领域。随着应用领域的拓展,对视觉系统的大视场、小型化和高精度等方面的要求越来越高。自然界中很多节肢动物的复眼以其结构紧凑、大视场和对物体运动高度敏感性等优势日益受到视觉测量领域的关注。因此本课题组以自然复眼为基础,设计制作了一种新型仿生复眼定位装置。本论文为实现复眼的标定与定位,从研制的复眼系统特征出发,观测分析了系统成像的畸变特性,提出了一种基于虚拟双球面的标定方案,对标定和定位过程的关键问题进行了探究,完成了对空间物体对象的三维定位,并对定位精度作出了评估。具体的研究内容如下:(1)对仿生复眼装置的机械结构、光学设计和图像采集系统等方面进行了详细描述,通过实验观测了不同子眼成像通道的畸变情况,指出了系统畸变特点,明确了系统标定对该仿生复眼系统的重要性。在调研多种非线性相机标定方法基础上,针对复眼大视场、子眼较多和畸变复杂等诸多特点,探讨了复眼系统的标定方法,提出基于虚拟双球面的标定方案,该方法通过构建图像点和对应入射光线的映射关系来实现标定。建立了标定数学模型,搭建了主要由单LED、二维转台、一维导轨和自动控制软件组成的标定平台。(2)从标定原理出发,合理规划了标定步骤,首先对标定平台进行了合理调整;接着针对光斑图像特征,确定了光斑中心提取步骤与算法;为保证空间靶标的均匀性分布,针对转台转动特点,引入正二十面体细分方案,合理规划了靶点位置;对多通道同时成像于同一图像面的状况,将转台转动角度和子眼位置纳入同一极坐标系中,探索了光斑与子眼之间的匹配方法;为建立非线性映射关系,在对三种映射方法分析对比中选择了最适合本系统的方法;最后对复眼开展了标定实验,建立了图像点和入射光线的非线性映射关系。(3)从双目视觉和系统标定原理出发,探讨了复眼定位理论,并以此为基础,研究了根据光斑点反求成像通道的方法。使用复眼对空间三维点进行了测量,结果表明,标定后的复眼装置在60°视场内的目标相对定位误差优于0.5%,定位角度均方根误差约为1.96 mrad。最后对简单面形进行了测量重构,表明了复眼的实际应用价值。
[Abstract]:As an important means of three-dimensional measurement technology, visual positioning has been widely used in the fields of industrial testing, medical diagnosis, special effect and security monitoring. With the expansion of the application field, the large field of view, miniaturization and high precision of the visual system are becoming higher and higher. The advantages of compact, large field of view and sensitivity to motion of objects are increasingly concerned in the field of visual measurement. Therefore, based on natural compound eye, a new type of bionic compound eye positioning device is designed and manufactured. This paper is designed to realize the calibration and positioning of the compound eye. From the features of the compound eye system developed, the system is observed and analyzed. A calibration scheme based on virtual bipheric surface is proposed. The key problems of calibration and positioning process are explored, the three-dimensional location of space object objects is completed and the positioning accuracy is evaluated. The specific research contents are as follows: (1) the mechanical structure, optical design and image mining of the bionic compound eye device. The distortion of different subocular imaging channels is observed by experiments, the characteristics of the system distortion are pointed out, and the importance of the system calibration to the bionic compound eye system is clarified. On the basis of investigating the calibration methods of multiple nonlinear cameras, many of the eyes are large and the distortion is complex and so on. The calibration method based on the virtual double sphere is proposed. The calibration method based on the virtual double sphere is proposed. The calibration model is established by constructing the image point and the mapping relation of the incident light. A calibration platform is set up. The calibration platform, which is composed of single LED, two dimensional turntable, one dimensional guide and automatic control software, is built. (2) from the standard. According to the fixed principle, the calibration steps are reasonably planned. First, the calibration platform is adjusted reasonably. Then the spot center extraction procedure and algorithm are determined according to the feature of the spot image. In order to ensure the uniformity distribution of the space target, the positive twenty plane subdivision scheme is introduced to the rotation characteristic of the turntable, and the target location is reasonably planned. In the same image plane, the rotation angle and the subeye position of the turntable are included in the same polar coordinate system, and the matching method between the spot and the eye is explored. In order to establish the nonlinear mapping relation, the method for the analysis and contrast of the three mapping methods is selected. Finally, the calibration experiment is carried out for the compound eye, The nonlinear mapping relation between the image point and the incident ray is established. (3) based on the binocular vision and the system calibration principle, the theory of the compound eye location is discussed. On the basis of this, the method of searching the imaging channel according to the light spots is studied. The measurement of the three-dimensional point of the space is carried out with the compound eye. The results show that the calibrated compound eye is in the 60 degree field. The relative positioning error of the target is better than 0.5%, the root mean square root error is about 1.96 mrad., and the simple surface shape is measured and reconstructed at the end, which shows the practical application value of the compound eye.

【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP391.41

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