Abstract: The present disclosure pertains to an unmanned aerial vehicle system. Some exemplary implementations may include: a mounting frame (110) onto which at least a payload (30) is affixed; a plurality of fuel cell stacks (50) operable in a predefined configuration, each of the plurality of stacks (50) being in a separate package; one or more tanks (60) configured to supply hydrogen tot the plurality of stacks; a propulsion system (70, 80) configured to receive an out put power generated from the plurality of stacks (50); and a power controller (40) configured to couple the plurality of stacks in the predefined configuration.

Abstract: A boom assembly for a rocket-launched spacecraft, the boom assembly comprising a plurality of rigid sections and a plurality of elastic sections that pivotally connect each of the rigid sections together so as to enable the boom assembly to be folded into a storage configuration and so as to enable the boom assembly to be automatically unfolded into a deployed configuration that provides the spacecraft with a large rigid extending platform. At least one of the rigid sections is mounted to the spacecraft so as to secure the boom assembly to the spacecraft. In one embodiment, a plurality of extendable components, such as solar panels and radar antennae, are mounted to the rigid sections so as to allow for storing and deploying the extendable components. In another embodiment, there may be no components mounted other than a length of wire or a length of metal tape which will allow the boom to act as an antenna.

Abstract: An erectable structure truss attachment joint includes a first truss having a casing containing a piston between a flange on the end of the casing and a wedge threadably mounted on an adjustment screw inside the casing. A tension rod passing through the wedge and the piston has a knob extending out of the casing on one end and an end bolt holding a leaf spring against the wedge on the other. A helical spring inside the casing creates pressure between the piston and the tension rod. A second truss has a notched retention wall at one end forming a chamber. The knob of the tension rod is inserted into the chamber to attach the two trusses. When the adjustment screw is tightened, the wedge acts against angled faces of the leaf spring on one side and the piston on the other side to create pressure against the piston and the leaf spring. The leaf spring exerts pressure against the end bolt to pull the tension rod into the interior of the casing.