Constraints Driven Design of a Surface Inflatable Habitat Module 2006-01-2101

Over the past two decades, the emergence of mature associative geometry modeling tools and the related sophistication in connected design/manufacture processes has enabled the design and realization of more complex, nonlinear structures. These techniques, first applied in the aerospace industry and currently being explored by architects, have matured into tools that can be used to optimize complex structural systems with irregular geometry. Potential advantages of this approach include: reduced mass penalty; optimized ECLSS and power sizing and performance; lower risk and lower cost in manufacturing; and flexibility, or the ability to customize individual vehicles according to function.

One area of space architecture where constraint driven design can become an invaluable tool is in the optimization of space inflatable habitats. The first endoskeletal hybrid space module - TransHab – was developed in the late 1990s at NASA’s Johnson Space Center. TransHab is a complex, semi-inflatable vehicle whose two basic configurations - launch and deployed - are each optimized for their respective environments. In the spring of 2005 a team of architects and structural engineers at *synthesis international*i completed a preliminary formal study in adapting the paradigm to design a module whose operations concept is similar to that of TransHab, but operating in a different environment - that of a planetary surface. This Surface Endoskeletal Inflatable Module [SEIM] is a fundamental element of the critical path for human exploration: the surface habitat.

To demonstrate the how space architecture designers can create intelligent associative models, this paper presents an iterative method for refining the shell and interior design of SEIM. The salient features of the design method are the use of 3D parametric modeling software for geometry definition - Generative Components by Bentley Systems, and the semiautomated two-way transfer of data between the design and analysis tools. The independent variable in this study is the geometry of the inflatable shell. The dependant variable is the interior spatial configuration. Fixed parameters include the geometry of the rigid frame and the stowed volume inside the launch platform. The parametric model allows rapid evaluation of the quality of the habitable spaces for a number of shell geometries.