Accuracy analysis of 3D model of open-pit mine based on tilt photogrammetry

Abstract

Mineral resources account for a large proportion in the development of national economy in China. The topography conditions around the mine site are complex, and accurate measurement of the mine topography can ensure that the mineral resources are mined safely and reasonably. The traditional mine survey has certain danger. With the advantages of flexibility and no site constraints, the UAV is equipped with a high-resolution lens and combined with tilt photogrammetry technology to obtain high-resolution images of multiple angles of the mine area and fine texture information of the feature surface in a short period of time. A total of 918 optical images were collected as raw data using a consumer-grade UAV equipped with a common optical lens. They were pre-processed and modeled to generate a high-precision, clear-textured 3D model of the study area. The root mean square of the pixel is 0.53 after aerial triangulation and adjustment. Compared with the actual measured value, the mean square error of plane coordinates is ±0.1cm, and the maximum error is 0.2cm, the mean square error of height is ±0.1cm, and the maximum error is 0.2cm. The mean square error of model plane coordinates is ±2.9cm, and the maximum error is 10.2cm. The mean square error of height is ±6.4cm, and the maximum error is 8.6cm. The results show that the production model meets the requirements of relevant specifications and the use of tilt photogrammetry in hazardous areas can improve the safety of surveyors.