Development of Aerial Based Dynamic Photogrammetry Capabilities for Measurement of Near- Source Surface Ground Motion from Buried Explosions
Abstract
While static photogrammetry can provide accurate three-dimensional (3D) before- and after- measurements of a target or surface, which can prove useful for a variety of applications such as change detection, new capabilities in dynamic digital photogrammetry have the potential to offer accurate temporal records of 3D surface deformation at any point in the field of view of two stereoscopic high-speed cameras. Commercial-off-the-shelf solutions for digital image correlation (DIC) were investigated in the development of aerial platforms for performing DIC. One of the objectives of this project was to be able to accurately record ground motion from a seismic source, such as a buried explosion, from high-speed cameras carried by two aerial platforms (in this case, small unmanned aerial systems). This is particularly challenging in that most DIC codes require accurate pre-test camera calibration and work best in laboratory conditions in which there is no relative camera motion. Investigations were undertaken to characterize the uncertainty in cases where the cameras experience relative motion as well as methods for mitigating or accounting for the relative motion in order to achieve more accurate temporal records of deformation using DIC techniques. The development of this capability started from simple dynamic test cases (such as an inflating inner tube buried in a pool of sand or a falling sheet of plywood with a speckled paint pattern), to the analysis of ground motion from buried explosions from near-stationary aerial platforms. Preliminary results show very promising agreement between displacements obtained using DIC analysis with ground truth instrumentation when methods are employed to account for the relative camera motion. Planned and ongoing work with explosions of differing yields at the same depth of burial, and explosions of differing yields but at the same scaled depth of burial are being investigated to determine the whether this technique has value for seismic and acoustic source definition for buried explosions.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMEP13A..08P
- Keywords:
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- 9805 Instruments useful in three or more fields;
- GENERAL OR MISCELLANEOUS;
- 5464 Remote sensing;
- PLANETARY SCIENCES: SOLID SURFACE PLANETS;
- 8040 Remote sensing;
- STRUCTURAL GEOLOGY;
- 8485 Remote sensing of volcanoes;
- VOLCANOLOGY