A method combining photogrammetry with ballistic analysis is demonstrated toidentify flying debris in a rocket launch environment. Debris traveling nearthe STS-124 Space Shuttle was captured on cameras viewing the launch pad withinthe first few seconds after launch. One particular piece of debris caught theattention of investigators studying the release of flame trench fire bricksbecause its high trajectory could indicate a flight risk to the Space Shuttle.Digitized images from two pad perimeter high-speed 16-mm film cameras wereprocessed using photogrammetry software based on a multi-parameter optimizationtechnique. Reference points in the image were found from 3D CAD models of thelaunch pad and from surveyed points on the pad. The three-dimensional referencepoints were matched to the equivalent two-dimensional camera projections byoptimizing the camera model parameters using a gradient search optimizationtechnique. Using this method of solving the triangulation problem, the xyzposition of the object's path relative to the reference point coordinate systemwas found for every set of synchronized images. This trajectory was thencompared to a predicted trajectory while performing regression analysis on theballistic coefficient and other parameters. This identified, with a high degreeof confidence, the object's material density and thus its probable originwithin the launch pad environment. Future extensions of this methodology maymake it possible to diagnose the underlying causes of debris-releasing eventsin near-real time, thus improving flight safety.
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