This paper reports recently completed structural dynamics experimental activities with new ultra-lightweight and inflatable space structures (a.k.a., "Gossamer" spacecraft) at NASA Langley Research Center, NASA Marshall Space Flight Center, and NASA Goddard Space Flight Center. Nine aspects of this work are covered: 1) inflated, rigidized tubes, 2) active control experiments, 3) photogrammetry, 4) laser vibrometry, 5) modal tests of inflatable structures, 6) in-vacuum modal tests, 7) tensioned membranes, 8) deployment tests, and 9) flight experiment support. Structural dynamics will play a major role in the design and eventually in-space deployment and performance of Grossamer spacecraft. Experimental research and development such as this is required to validate new analysis methods.
This textbook is intended as a core text for courses on aeroelasticity or aero-elasto-mechanics for senior undergraduate/graduate programs in aerospace and mechanical engineering. The book focuses on the basic understanding of the concepts required in learning about aeroelasticity, from observation, reasoning, and understanding fundamental physical principles. Fundamental and simple mathematics will be introduced to describe the features of aeroelastic problems, and to devise simple concurrent physical and mathematical modeling. It will be accompanied by the introduction and understandings of the mechanisms that create the interactions that generate the aeroelastic phenomena considered. The students will also be led to the relation between observed phenomena, assumptions that may have to be adopted to arrive at physical and mathematical modelling, interpreting and verifying the results, and the accompanied limitations, uncertainties and inaccuracies. The students will also be introduced to combine engineering problem solving attitude and determination with simple mechanics problem-solving skills that coexist harmoniously with a useful mechanical intuition.
Design and Fabrication of Large Polymer Constructions in Space is a ground-breaking study of the polymeric materials, advanced chemical processes, and cutting-edge technology required in the construction of large polymer-based structures for space, when all steps in the process are carried out in the space environment, whether in orbit, in deep space, or on the surface of a moon, asteroid, or planet.The book begins by introducing the fundamentals and requirements of large constructions and inflatable structures for space. The next section of the book focuses on the utilization of polymeric materials within the space environment, examining the effects on materials (vacuum, plasma, temperature), the possible approaches to polymerization both in space and in orbit, the preparation and structure of polymer composites, and the methods for testing materials and structures in terms of strength, defects, and aging. Three chapters then cover how these materials and techniques might be applied to specific categories of construction, including larger space habitats, supporting space structures, and ground infrastructure. Finally, the financial aspects, the consequences for human space exploitation, and the possible future developments are discussed.Using materials science to push the boundaries of construction for space exploration and exploitation, this book is a unique resource for academic researchers and advanced students across polymer science, advanced materials, chemical engineering, construction, and space engineering, as well as for researchers, scientists and engineers at space agencies, companies and laboratories, involved in developing materials or technology for use in space. This is also of great interest to anyone interested in the role of materials science in the building of large space stations, spacecraft, planetary bases, large aperture antenna, radiation and thermal shields, and repairmen sets. Describes the role of polymers in the construction of large space habitats, supporting space structures, and ground infrastructure Explains polymerization in the Earth’s orbit and in space, covering material specifications, control of curing, and the effects of interaction with the external environment Presents the possible testing methods, including strength evaluation, defect detection, and aging tests of materials and constructions
