This innovation is a weight-optimized, inflatable structure that incorporates radiation shielding materials into its construction, for use as a habitation module or rover vehicle. An inflatable fabric enclosure can provide better radiation protection than an aluminum structure (which generates harmful secondary radiation). The proposed inflatable structure represents a hybrid restraint system in which a gas-impervious cloth barrier is structurally reinforced using an external grid of cordage. This hybrid design is based upon the premise that materials providing the surface coverage and impermeability necessary for fluid containment are ill-suited to withstand global pressure and mass loads--and vice versa. Segregating material roles enables significant weight reduction while satisfying stringent requirements for strength, dimensional stability, abrasion and impact resistance, and thermal control of the interior volume.