【作者】 宋万忠；

【导师】 苏显渝；

【作者基本信息】 四川大学 ， 光学， 2002， 博士

【摘要】 多视点距离像的配准与复杂曲面展平一直是光学三维传感应用研究中的重要课题，是复杂物体建模和计算机辅助产品设计(特别是二维与三维交互设计)的基础，对光学三维传感的应用和推广具有重要意义。 本文对光学三维传感中多视点距离像的配准与复杂曲面展平问题分三个部分进行了研究：三维坐标校准、多视点距离像配准和多边形曲面展平。研究内容和取得的成果如下： 1．基于相移技术和条纹投影的位相测量轮廓术中常用的校准方法需要一个精密的平移工作台。校准时需要将校准平面进行多次平移，每次平移都需要进行一次测量，而且校准过程中需要保持标准平面的稳定，这些特点限制了便携式测量系统的开发。本文首次提出了一种只需要一次测量即可完成高度和横向坐标校准的方法，该方法在保证精度的同时提高了校准过程的自动化程度。 2．由于物体表面常常存在自遮挡，而且测量系统结构本身也会产生阴影，这就使得对复杂物体需要进行多次不同视点位置的测量。针对两幅距离像间的配准，我们分别从重叠区域检测、控制点选取、对应点计算和对应点有效性检查四个方面提出了多种加速方案，从而实现了大数据量距离像的快速局部配准。对于多幅距离像，两两配准叠加后会出现局部配准误差的积累和放大。基于虚拟点对约束的概念，我们提出了一种积累误差扩散算法，其基本思想是在尽量保证局部配准结果的前提下，使累积误差在各距离像间均匀分布。 3．非结构化网格常被用于近似描述自由曲面，我们提出了一种针对这类曲面的分步展平算法．该算法把全局参数化技术用于生成初始展平估计，从而实现了对参数曲面和多边形曲面的统一处理。结合曲面展平在制鞋CAD中的应用，我们提出了包括测量数据预处理、楦面约束展平和展平图质量评价的完整解决方法，使用该方法可以得到和手工展平结果相近的展平图。更多还原

【Abstract】 This dissertation addresses the following three problems of optical three dimensional sensing: coordinates calibration in phase-measuring profilometry (PMP), multi-view registration of range images and flattening of doubly curved surfaces. The principal contributions of this dissertation are:1. It presents a new method for the system calibration in PMP. With a special calibration gauge, both the phase-height mapping and lateral coordinates calibration could be done simultaneously through only one measurement. By an iterative procedure, this method is able to recover the continuous phase distribution of all steps with same height.2. It introduces a fast iterative pairwise registration method. Which combines four acceleration techniques: fast detection of overlapped regions by reverse calibration, more-careful selection of control points, fast surface closet point computation with closet vertex caching and compatibility test of pairing points based on the difference of modulation. With respect to the registration of multi-view range images, a relaxation strategy is introduced to spread evenly the accumulated registration errors among all views, with the assumption that the pairwise registrations are nearly good.3. It presents a method for constructing the initial flattening guess of triangulated surface. By this method, parametric and polygonal surfaces could be flattened in a general way. Residual energy distribution pattern is proposed to evaluate the global quality of flattened pattern. Also considered is the flattening of surfaces with arbitrary darts and gussets. With the application of flattening of surfaces in shoe CAD using laser range images, it proposes a whole processing procedure starting from the preprocessing of points cloud.更多还原