Implosion-resistant lightweight membrane shell devices for high-pressure applications

A buoyancy device comprising:

• a toroidal membrane shell having an inner surface, an outer surface, and an interior space bounded by said inner surface;
• a toroidal entanglement of fibers including shape memory alloy fibers and magnetic fibers, said toroidal entanglement situated in said interior space of said toroidal membrane shell, said toroidal entanglement characterized by shape memory of said shape memory alloy fibers and by repositioning of said magnetic fibers, said shape memory of said shape memory alloy fibers exerting a return force to return said shape memory alloy fibers to a memorized shape, said shape memory of said shape memory alloy fibers resulting from subjection of said toroidal entanglement to heating, said repositioning of said magnetic fibers resulting from subjection of said toroidal entanglement to an external magnetic field;
• wherein, in accordance with said shape memory of said shape memory alloy fibers, and further in accordance with said repositioning of said magnetic fibers, said toroidal entanglement exerts an outward pressure upon said inner surface of said toroidal membrane shell.

A method for making a buoyancy device, the method comprising:

• placing a fibrous tangle inside a membrane shell, said membrane shell describing a closed three-dimensional geometric figure and having an inner surface, an outer surface, and an interior space bounded by said inner surface, said fibrous tangle being a tangle of a plurality of shape memory alloy fibers;
• applying heat to said fibrous tangle placed in said interior space, said applying of said heat being performed so as to imbue said fibrous tangle with an austenitic shape memory, wherein said fibrous tangle thus imbued exerts an outward pressure upon said inner surface of said membrane shell.