1819. Pultrusion With Thermoplastics for the Fabrication of Structures in Space

Paper

Abstract

One of the most costly aspects of space exploration is the transportation from earth-to-orbit. If the volume of the cargo can be compressed, the requirements with regard to cargo bay size can be reduced correspondingly. This, in turn, would allow for a reduction in the size of the transporting vehicle. In order to achieve high cargo density for structures to be used in space, the pultrusion method of manufacture is proposed. In this mode of operation, the structural materials would be transported in coils or flat bundles and fabricated in space using space based pultrusion machines. Some of the potential applications for space manufacture of structures using pultrusion fabrication include large deep space antennae, staging platforms for equipment and supplies for manned planetary missions, and shelters for planet-based camps. by using the pultrusion method of fabrication, long continuous lightweight structural elements can be manufactured such as the ribs in an antenna, beams in a space platform, or the rof trusses in a planet-based shelter. The stock material proposed for pultrusion manufacture in space is powder impregnated high-strength, high modulus fiber; the powder material to consist ofa thermoplastic compound such that any structural element fabricated at Earth base can later be consolidated and reformed in a pultrusion die. The proposed method of joining the structural profiles is by fusion welding using solar energy. One type of lunar shelter might consist of a series of arches over which aluminized plastic film is stretched to shelter astronauts and equipment from solar radiation, while a deep space antenna might consist of a series of pultruded radial ribs with cross members consisting of an Archimedian spiral. The chemistry and techniques of pultrusion fabrication as well as quality testing will be discussed. The materials and procedures necessary for pultrusion fabrication in a space environment will be emphasized.