Advanced, lightweight, inflatable structures are very attractive in space exploration applications. This type of structure design requires the use of textile, film and foam materials in order to obtain the structure packaging and its subsequent in situ deployment, reducing payload volume and mass with respect to the rigid structures and ultimately reducing launch costs. The inflatable structures are then conceived to be used as booms, trusses, modules, protection shields, or can be configured to almost any simple shape. In this paper experimental investigations in terms of the mechanical and environmental testing of two inflatable fabric materials are presented, one having structural and bladder functions and the second having only structural. For the second fabric, an internal bladder has been provided and two different seaming techniques were evaluated. Heavy duty sewing patterns were adopted on the fabrics and tested in order to register their mechanical performance and reveal which parameters should be varied for greater performances. However, the lightweight, flexible and highly damped nature of inflated structures poses difficulties in ground testing. In this study, we show the deployment behavior in vacuum conditions depending on the packaging configuration and its relation. This aspect was studied for higher deployment reliabilities and for constraint characteristics provided while stowed in the launch phase. The inflation occurred using only the residual air. Outgassing tests on selected materials were also performed in order to obtain their total mass loss in vacuum. This type of test represents a fundamental space material investigation, due to the Outgassing contamination effects on neighboring surfaces, particularly relevant in terms of optics, cameras or optics based instruments contamination. All the tests were performed in the SASLab Laboratory, using mechanical machines, the Space Environment Simulator and Outgassing Testing Facility.
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