Videogrammetric quantification of deployment behavior of rollable Membrane Shell Technology apertures

This paper provides an overview of a videogrammetric methods developed to capture and quantify roll deployment behavior of Thin Film Membrane Aperture Shells. This paper then describes results of using this method to capture quantifiable empirical data about the deployment of such shells. A key advantage of such shells is their ability to be compactly roll stowed (i.e. no folding) yet passively self deploy and self rigidize. While the deployment of such shells is inherently a simple process driven by the release of stowed strain energy that causes the doubly curved shells to self deploy back to their original shape, a range of subtle differences can only be observed with detailed quantitative data that this new test method provides. After reviewing Membrane Shell Technology (with a special focus on stowage and deployment) and the developed videogrammetric method, quantitative deployment trajectory results from 50+ separate deployment tests are reviewed. While overall behavior of shell deployment was found to remains similar across a wide range of shell design parameters, factors that particularly effect portions of the deployment were found to include the shell prescription, and stowage diameter. Other effects such as starting boundary condition, type and method of stowage retention were found to be important as well.