High-altitude payload retrieval (HAPR) apparatus and methods of use
The disclosure provides an HAPR apparatus comprising an inflatable frame configured to generate canopy extension based on surrounding atmospheric pressure. The inflatable frame has a first collapse load limit less than the weight of the canopy at a first pressurized state less than 75 kPa and a second collapse load limit greater than the weight of the canopy at a second pressurized state of greater than 95 kPa. The internal pressure of the inflatable frame is typically about 101 kPa. The HAPR apparatus allows ascension with the canopy hanging under its own weight to reduce ascension time, then generates canopy extension prior to release in essentially a zero velocity, zero dynamic pressure condition.
1. A High-Altitude Payload Retrieval (HAPR) apparatus for full planform deployment at high altitude comprising:
a canopy comprising a flexible material having a weight;
a line channel passing through the canopy;
an inflatable frame coupled to the canopy, where the inflatable frame is configured on the canopy to establish a projected span of the canopy when inflated at a ground level to a non-wrinkling condition, and where during ascent from the ground level, the inflatable frame is flexible and non-rigid at a first pressurized state when at elevations less than or equal to approximately 33,000 feet and the inflatable frame is rigid at a second pressurized state when at elevations greater than approximately 33,000 feet;
a plurality of fastening devices coupled to a perimeter of the canopy and configured to fasten a plurality of lines to the canopy; and
wherein the canopy comprises:
an upper skin having a leading edge, trailing edge, a first lateral edge, and a second lateral edge generally opposing the first lateral edge, where the inflatable frame is coupled to the upper skin;
a lower skin;
a plurality of rib panels each having an upper edge and a lower edge, with at least a portion of the upper edge affixed to the upper skin and at least a portion of the lower edge affixed to the lower skin, and the plurality of rib panels establishing a plurality of elongated cells, where each cell is defined by a portion of the upper skin, a portion of the lower skin, and a first rib panel and a second rib panel, where the first rib panel and the second rib panel are rib panels in the plurality of rib panels.
2. The HAPR apparatus of claim 1 the projected span of the canopy is equal to at least 30% of a maximum constructed dimension of the constructed shape of the canopy.
3. The HAPR apparatus of claim 1 where the inflatable frame comprises a plurality of inflatable members and where each inflatable member in the plurality of inflatable members surrounds an interior volume, and where each interior volume in the plurality of inflatable members is in fluid communication with every other interior volume in the plurality of inflatable members, and where each inflatable member is coupled to the canopy at one or more connection points on the canopy, and where the each inflatable member comprises an inner layer and an outer layer at least partially surrounding the inner layer, where the outer layer comprises a braided fiber reinforcement constructed to provide a first collapse load limit of the inflatable frame less than the weight of the canopy at the first pressurized state and constructed to provide a second collapse load limit of the inflatable frame greater than the weight of the canopy at the second pressurized state.
4. The HAPR apparatus of claim 3 further comprising a manually operated mechanism having an open position and a shut position and configured to allow fluid communication between at least one interior volume in the plurality of inflatable members and an atmosphere surrounding the canopy when in the open position and configured to prevent fluid communication between the at least one interior volume in the plurality of inflatable members and the atmosphere surrounding the canopy when in the shut position.
5. The HAPR apparatus of claim 4 where the line channel surrounds the centroid of a constructed shape of the canopy and where the each inflatable member in the plurality of inflatable members extends in a direction from the line channel toward a perimeter of the constructed shape of the canopy.