Grating projection scanning equipments are often used to detect 3D data of industrial products,such to acquire precise surface size of products. Photographs merging has a large accumulated error in the measurement of large-size surface due to the principle of uncoded point three-point fix. Using close-range photogrammetry method to build three-dimensional measurement of uncoded point group is an effective means to improve accuracy of the three-dimensional measurement. Describes the principles and methods of close-range industrial photogrammetry systematically. A multi-camera station close-range photogrammetry method combined with the grating projection scanning method is introduced to achieve accurate measurement of large-size objects. A case study of surface measurement of motor vehicles shown that, compare with a separate raster scan method, close-range photogrammetry combined with the raster scan method not only improve the scanning efficiency but also increased the accuracy of the scanning of large-size objects substantially.%工业产品的三维数据检测常常使用光栅投影扫描设备获得被测物体精确的表面尺寸.由于其照片拼合依据非编码点三点定位原理,因而在测量大尺寸物体表面时,具有较大的累计误差.通过近景摄影测量方法构建三维测量的非编码点群,是提高三维测量精度的一种有效手段.阐述了近景摄影测量的原理及方法,提出了利用多摄站近景摄影测量结合光栅投影扫描的方法实现大尺寸物体精确测量.以汽车外表面测量为例,通过采用单独使用光栅投影扫描设备与近景摄影测量结合光栅投影扫描两种不同的方法,对大尺寸物体表面测量的结果进行对比,其结果表明,使用近景摄影测量方法不仅提高了扫描效率,而且大幅度提高了大尺寸物体的扫描精度.
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