Various techniques are provided for an energy absorbing fluid bladder. In one example, the fluid bladder includes a bladder body and a perforated baffle structure. The perforated baffle structure can be disposed within the bladder body and configured to mitigate a pulse of fluid (e.g., fuel) moving within the bladder body before the pulse reaches the bladder body. Related methods are also disclosed.

Various techniques are provided for an expandable energy absorbing fluid bladder. In one example, the fluid bladder includes a primary portion and a secondary portion. The secondary portion can be configured to expand or increase in volume when the fluid bladder is subjected to a pulse greater than a threshold pulse. Expansion of the secondary portion can allow fluid or additional fluid to flow into the secondary portion and thus decrease a peak pulse and, thus, avoid rupture of the fluid bladder.

A quadrotor UAV including ruggedized, integral-battery, load-bearing body, two arms on the load-bearing body, each arm having two rotors, a control module mounted on the load-bearing body, a payload module mounted on the control module, and skids configured as landing gear. The two arms are replaceable with arms having wheels for ground vehicle use, with arms having floats and props for water-surface use, and with arms having pitch-controlled props for underwater use. The control module is configured to operate as an unmanned aerial vehicle, an unmanned ground vehicle, an unmanned (water) surface vehicle, and an unmanned underwater vehicle, depending on the type of arms that are attached.

An aircraft has a fuel cell, a battery configured to be charged by the fuel cell, a supercapacitor configured to be charged by the fuel cell, and a power management unit configured to receive electrical power from the fuel cell, the battery, and the supercapacitor.

A quadrotor UAV including ruggedized, integral-battery, load-bearing body, two arms on the load-bearing body, each arm having two rotors, a control module mounted on the load-bearing body, a payload module mounted on the control module, and skids configured as landing gear. The two arms are replaceable with arms having wheels for ground vehicle use, with arms having floats and props for water-surface use, and with arms having pitch-controlled props for underwater use. The control module is configured to operate as an unmanned aerial vehicle, an unmanned ground vehicle, an unmanned (water) surface vehicle, and an unmanned underwater vehicle, depending on the type of arms that are attached.

An air and land multimodal vehicle comprises a frame, a propeller engine attached to a first location of the frame supplying power and torque to a propeller, a ground engine attached to a second location of the frame supplying power and torque to one or more ground traction elements, and a flexible wing releasably connectable to the frame, wherein the propeller engine is vertically and horizontally spaced from the ground engine.

A fuel vent connector includes a longitudinal axis and a flow path a long the longitudinal axis. The connector further includes a first portion pivotally supporting a plurality of fingers, each finger amongst the plurality of fingers having a latching head biased radially outwardly and configured to latch within a fuel vent opening. The connector further includes a second portion biased longitudinally away from the first portion with respect to the longitudinal axis. The flow path extends through the first and second portions, and longitudinal movement of the second portion towards the first portion moves the fingers radially inward.

A vent valve includes a vent body including an outlet and at least one inlet, a main chamber, a main closable device movable from an open position to allow fluidic communication between the main chamber and the outlet, to a closed position to block fluidic communication between the main chamber and the outlet, and a first tubing having a first end and a second end, the first end connected to a first inlet, the second end spaced from the vent body, the first tubing further including a first closable device adjacent the second end. The first closable device allows fluidic communication between an exterior of the first tubing and an interior of the first tubing in a first orientation of the vent valve, and blocks fluidic communication between the exterior of the first tubing and the interior of the first tubing in a second orientation of the vent valve.

A vehicle is provided which includes a vehicle support structure having a casing of a rocket motor that is arranged to sustain an inertial load generated, at least in part, by the vehicle when the rocket motor is inactive. In some examples, the vehicle is a land-based vehicle and the vehicle support structure includes a roll cage. In other examples, the vehicle is a helicopter and the vehicle support structure is a skid structure.

An air and land multimodal vehicle comprises a frame, a propeller engine attached to a first location of the frame supplying power and torque to a propeller, a ground engine attached to a second location of the frame supplying power and torque to one or more ground traction elements, and a flexible wing releasably connectable to the frame, wherein the propeller engine is vertically and horizontally spaced from the ground engine and the ground engine extends at least six inches below a base of the frame.