W. K. Belvin, NASA Langley Research Center, Hampton, VA
NASA is in the process of developing vehicles and systems for crewed missions to low Earth orbit (replacing the Space Shuttle System), Lunar transport of crew and cargo, and long-duration Lunar surface missions. Preliminary design studies are being used to develop system concepts and requirements for each of the major exploration elements. For example, the Crew Exploration Vehicle (now known as Orion) completed several design analysis cycles in 2006. In 2007, the Lunar Lander (now known as Altair) began system level conceptual design of the ascent and descent stages. For each of these design efforts, a Structures and Mechanisms Subsystem (SMS) team was responsible for investigating and selecting preliminary structural load paths, structural concepts, and material systems, while interacting with other vehicle subsystems to insure that system level requirements and constraints were satisfied. Rapid physics-based modeling of vehicle loads and structural concepts enabled accurate prediction of the vehicle’s strength, stiffness, stability, and mass. To optimize the vehicle performance, the SMS team evaluated advanced material systems and alternative structural concepts. For example, potential Orion crew module mass savings were identified if a composite material system was used for the pressure vessel instead of Al-Li metallic. Similarly, the Altair lander was found to be severely mass constrained. Lightweight, environmentally durable materials were identified as enabling to the Lunar mission using the current architecture. This presentation will briefly review the current space exploration architecture and the major elements needed for initial Lunar missions. Experience from the SMS team is used to identify key design drivers and constraints for these vehicles. The need for advanced structural and multifunctional material systems with high specific strength and stiffness will be highlighted.
Summary: This presentation will briefly review the current space exploration architecture and the major elements needed for initial Lunar missions. Experience from the SMS team is used to identify key design drivers and constraints for these vehicles. The need for advanced structural and multifunctional material systems with high specific strength and stiffness will be highlighted.
