Pressure airship model structural analysis and deformation measurement using photogrammetry

The deformation of an airship model is measured by a non-contact photogrammetric system. The application of the photogrammetry on the ultra-lightweight structures and space inflatable structures are introduced firstly. Then the larger deformation region, which is determined by finite element analysis, of a 3m-length airship model was measured by a photogrammetric system which consists of six 8.0 megapixel Canon350D digital cameras and PhotoModeler photogrammetric software. All the images gained by cameras were processed by PhotoModeler and the 3D coordinates of all the retro-targets on the airship were given. Since it is not practical to obtain images of the airship skin in an uninflated state to obtain the true zero stress state of the airship, the geometry parameters at 0Pa internal pressure was gained by theoretical calculated. The radical strain and longitudinal strain in that region of the airship model at different pressure was gained finally. The effectivity of deformation measurement of the airship by photogrammetry was verified through the study, which will guide the large airship design and analysis in the future.