A method based on structure-from-motion photogrammetry to generate sub-millimetre-resolution digital elevation models for investigating rock breakdown features

Abstract

Abstract. We have generated sub-millimetre-resolution DEMs of weathered rock surfaces using SfM photogrammetry techniques. We apply a close-range method based on structure-from-motion (SfM) photogrammetry in the field and use it to generate high-resolution topographic data for weathered boulders and bedrock. The method was pilot tested on extensively weathered Triassic Moenkopi sandstone outcrops near Meteor Crater in Arizona. Images were taken in the field using a consumer-grade DSLR camera and were processed in commercially available software to build dense point clouds. The point clouds were registered to a local 3-D coordinate system (x, y, z), which was developed using a specially designed triangle-coded control target and then exported as digital elevation models (DEMs). The accuracy of the DEMs was validated under controlled experimental conditions. A number of checkpoints were used to calculate errors. We also evaluated the effects of image and camera parameters on the accuracy of our DEMs. We report a horizontal error of 0.5 mm and vertical error of 0.3 mm in our experiments. Our approach provides a low-cost method for obtaining very high-resolution topographic data on weathered rock surfaces (area < 10 m2). The results from our case study confirm the efficacy of the method at this scale and show that the data acquisition equipment is sufficiently robust and portable. This is particularly important for field conditions in remote locations or steep terrain where portable and efficient methods are required.

Measuring Change Using Quantitative Differencing of Repeat Structure-From-Motion Photogrammetry: The Effect of Storms on Coastal Boulder Deposits

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Characterization of Rock Samples by A High-Resolution Multi-Technique Non-Invasive Approach

“…In fact, such models represent a valuable tool that can be exported easily, 3D printed and successively inspected by experts and scientists of various disciplines. Portable document format (PDF) dynamic 3D representations and movies of samples but also of complex shape bodies can be made and represent useful tools for operators and technicians that need to study complex shape bodies on their own office computers without any direct contacts with the bodies themselves, see for example [76] ( [37,77,78] and references therein). TLS technology, for example, measures distances between the emitter of the laser ranging system and the reflecting surface of the illuminated objects to produce point clouds over the target field of view.…”

Analysis of Differences in 3d Building Information Modeling

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