Deployment analyses of membrane structure systems with inflatable tubes for future space applications

Deployment behaviour of inflatable tubes folded different patterns are compared in this paper through deployment experiments and deployment analyses with the aim of applying the future large membrane space structures. As for deployment experiments, three folding patterns, which are rolled-up, zigzag and modified zigzag, are compared. The inflatable tube in modified zigzag folding pattern deploys stably and sequential because of the stable flow of supplied air around the fold lines. As for deployment analyses, the folding process making zigzag folding line and rolled-up folding line are re-created in the analyses, and the behaviour of the supplied airflow around the fold lines are compared taking over the shape and the stress of fold lines computed the folding processes. The rolled-up model deploy sequential based on its fold line like the experimental result, but the model in zigzag folding pattern deploy non-sequential because the airflow over at the zigzag fold line. This airflow over the fold line may be one of the causes of the resistance to airflow which cause the unstable deployment of zigzag folding pattern.