【作者】 王大为；

【导师】 邾继贵；

【作者基本信息】 天津大学 ， 测试计量技术及仪器， 2007， 硕士

【摘要】 三维形貌拼接技术作为三维形貌测量中的核心技术,直接影响到三维形貌测量系统的精度和使用效果。目前的三维形貌拼接方法有多种,借助于辅助精密设备的拼接方法算法简单,但系统灵活性差,系统成本较高;通过从相邻测量区域的重合部分提取信息实现拼接的自由拼接方法,使用灵活,但容易产生累计误差,若在表面粘贴人工标记点则干扰了被测形貌自身特征,影响测量真实性。针对上述方法存在的问题,研究了基于拼接靶标的三维形貌拼接技术。通过高分辨率大视场的专业数码相机对分布在测量空间的全局控制点进行拍摄来建立全局坐标系,以它为基准,并引入拼接靶标作为中介对各局部测量数据进行拼接,该方法从理论上避免了多次拼接产生的累计误差,同时拼接靶标的使用,避免了对被测物体表面特征的干扰。论文的主要研究内容:一、研究了一种无表面干扰的三维形貌拼接技术——基于拼接靶标的三维形貌拼接技术。通过全局控制点建立全局坐标系,引入拼接靶标作为中介,对各局部测量数据进行拼接。二、针对大视场下全局坐标系的建立,研究了一种基于近景摄影测量中光线交汇约束的单摄像机多摄站全局控制点定向方法。同时还研究了全局控制点和拼接靶标的设计和识别。三、针对拼接过程中拼接速度的问题,结合近景摄影测量中的解析处理方法,研究了单摄像机单次成像求解转换矩阵的方法,并结合实验进行了精度分析。四、进行了基于拼接靶标的三维形貌拼接实验,分别应用立体光线交汇定向的方法和单摄像机单次成像的方法实现拼接,并对实验结果进行了分析比较。更多还原

【Abstract】 3D surface mosaic technology as the core technology of the 3D surface measurement directly influences the precision and use effect of 3D surface measurement system. There have a lot of techniques of 3D surface measurement. The methods that ask for help of auxiliary precise equipments have simple algorithms, but the systems based on these methods have lower adaptabilities and higher cost. The mosaic methods that extract information from overlapping part of adjacent regions to realize mosaic is flexible but easily create accumulative error. And affixing artificial marking points on the measured object would interfere with the characteristic of measured surface. A 3D surface mosaic technology based on a mosaic target is studied. With the high-resolution camera and several control points, a global coordinate system with high precision is set up. Then, by introducing the mosaic target, the translation between the global coordinate and the measuring coordinate can be established. The 3D data obtained from different viewpoints thus can be translated into a unique frame of reference. So the final results can be obtained. This method avoids creating mosaic accumulative error. Using the mosaic target avoids interfering with the characteristic of measured surface.The main contents of the thesis are as follows.1. The study on the 3D mosaic technology without surface interference—the 3D mosaic technology based the mosaic target. With several control points, a global coordinate system with high precision is set up. And by introducing the mosaic target, the translation between the global coordinate and the measuring coordinate can be established.2. An orientation method for global control points based on ray intersecting from the close-range photogrammetry is studied. The design and identification of global control points and the mosaic target is also studied.3. A method using single image to gain the transition matrix is studied aiming at raising the mosaic speed. Precision analysis is given by the experiment.4. The 3D mosaic experiment based the mosaic target is given. The method that uses single image to gain the transition and the method based on ray intersecting are used to complete the mosaic.更多还原