Unpressurized Orbital Hangars in Geolunar Space
Bernasconi, M.C.
MCB Consultants

We present here the results of preliminary investigations aimed at defining a range of evolutionary products in support of exploration activities, and in preparation of a utilization effort, focusing on lightweight three-dimensional structures creating large enclosures that can find use in early development steps, particularly in the orbital environment (hangars, work sheds, thermal enclosures, garages, and derivative objects).

The idea of in-situ assembly, maintenance, or repair activities naturally leads to a requirement for obtaining a measure of protection from local environment factors to persons and devices. A hangar offers protection against al least ultraviolet radiation and against extreme temperatures and lighting conditions; by enclosing the maintenance hardware, it support control of part and tools e.g. by offering stowage volumes; it may also give some shielding against micrometeoroid and debris. Already May and colleagues (1963) discussed the concept of a maintenance hangar: inflatable and rigidizable concepts emerged as the most advantageous ones.

We accordingly propose to address the hangar realization through the use of chemically--rigidized inflatable structures, whose technological evolution in functional capability (e.g., to "garages" on planetary surfaces, low-pressure greenhouses) can result from a step-wise, low-risk and low-cost development of the basic technologies, with objects of incremental capability serving as demonstrator for the successive stage. The listing of preliminary requirement for orbital maintenance hangars leads to the discussion of other early applications for this kind of items.

Typically, a hangar-like structure consists of a 3-dimensional lattice of rigidizable tubes (the skeleton), supporting the required wall elements. In its simplest form, skeleton follows the edges of a polygonal prism, with longitudinal columns and two toroidal polygons a the ends, and a set of spokes connecting one base of the prism to a rigid interface to e.g. the supporting spacecraft; of course, other forms are possible and may be of advantage. In addition to the technological solutions for the skeleton, issue considered include functions and forms of wall elements, need for and realization for a door, internal furnishing elements. The presentation concludes with the outline of technology needs and of a follow-up development plan.

References

Marco C Bernasconi (1999). Space-Habitat Uses of Expandable Flexible Structures. Paper presented at the ISST'99 - International Symposium on Space Travel, Bremen (Germany), 21-23 April.

Marco C Bernasconi & Meindert Versteeg (2004). A Review of Inflatable, Habitable Structures. Presentation at the 2nd European Workshop on Inflatable Space Structures, Tivoli (Italy), June 21-23.

Krafft A. Ehricke (1970a). Earth-Moon Transportation. Paper AAS-70-058 presented at the 16th AAS Annual Meeting, Anaheim (CA); also: Adv Astronautical Sci 28, 401-452.

CB May, PN van Schaik, & FW Forbes (1963). Space Maintenance Hangar Concepts. Paper presented at the 1st Aerospace Expandable Structures Conference , Dayton (Ohio), October 23-25; Transactions, 137-167.

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PPH-08-071