Verification and Validation of an Innovative Inflatable Structure Design

An inflatable habitat is a pressure vessel with flexible shell. Notable features such as low weight, large inflated operational volume, and small pre-deployment volume offer significant advantages over traditional rigid metallic and composite habitat structures. Conventional designs suffer from indeterminacy of load sharing between meridional and circumferential members as well as the internally rigid metal support structure. The designs must functionally index the meridional and circumferential members to one another to minimize sensitivity to manufacturing, handling and operational trauma, all the while maintaining their independent load carrying roles. This design process results in oversized members to account for load uncertainties. The unique Ultra High Performance Vessel (UHPV) technology provides the solution to the design and manufacture of robust inflatable structures with exceptional accuracy and dimensional stability. UHPV technology provides high shell load containment architecture with fully determinate load pathways that can be modeled mathematically. The lightweight, low cost inflatable fabric structure, consisting of barrier film layers, carrier cloth containment layers, and pressure restraint tendons can be designed and fabricated to provide an accurate geometry without the need for an internal skeletal frame. Eliminating the need for a rigid internal load-bearing frame allows the collapsed inflatable to be packaged in the smallest possible volume. To bring this innovative inflatable design to use for lunar habitats, airlocks and myriad other space environment and containment applications, a verification and validation plan using both testing and predictive analytical models is proposed to conclusively demonstrate that the fully load-determinate UHPV can meet all structural design requirements for habitable space structures and be accurately and repeatedly manufactured.