Abstract: An innovative new structure, called ChamberCore, is disclosed that is damage tolerant, easy to manufacture, and has an inherent design feature that can be exploited to drastically reduce acoustic transmission through the structure. The structure is composed of previously cured tubes that are sectioned to form chambers and co-cured with facesheets to form a sandwich-type structure. Damage tolerance is derived from the fact that the structure has no weak facesheet-core interface as found in traditional sandwich-type structures. Additionally, each chamber has a hole to it through the inner facesheet effectively converting it into a Helmholtz resonator. These resonators can be tuned to attenuate broadband or specific acoustic transmission through the structure.

Abstract: The space-based solar power generating system is comprised of a flexible thin film photovoltaic sheet supported as a sail in the solar wind. The solar wind provides pointing support, deployment support, and structure stiffness without a heavy backup structure. A high Isp electric propulsion system is used to counteract the force exerted on the sail by the solar wind.

Abstract: A plurality of Helmholtz resonators with varying physical characteristics are mechanically coupled within a structure to drastically reduced acoustic transmission through the structure or along a pipe. These mechanically coupled resonator structures produce much flatter broadband acoustic attenuation than uncoupled resonators.