High altitude balloon systems and methods using continuous multi-compartment super pressure balloon
Features for a high altitude lighter-than-air (LTA) system and associated methods. A zero-pressure balloon (ZPB) is attached in tandem with one or more variable ballast air super-pressure balloons (SPB) having a continuous skin and multiple SPB compartments. The ZPB provides lift for the system while the multi-compartment SPB uses a centrifugal compressor to provide a variable amount of ballast air by pumping in or expelling out ambient air. Various performance targets relating to ascent rate, descent rate, range and maximum altitude are achievable with various scaled versions of the basic design of the LTA system. Navigation and control techniques, such as high altitude station-keeping approaches, are made possible with the LTA system.
1. A balloon system for altitude control of a lighter than air (LTA) system, comprising:
a zero pressure balloon (ZPB);
a continuous, multi-compartment super pressure balloon (SPB) attached to the ZPB, wherein:
the continuous, multi-compartment SPB includes a continuous outer skin defining an interior volume, the interior volume in fluid communication with ambient air of a surrounding atmosphere and configured to receive the ambient air into the interior volume of the SPB to increase a downward force to the balloon system and to emit the ambient air from the interior volume of the SPB to the surrounding atmosphere to decrease the downward force to the balloon system,
the continuous, multi-compartment SPB is configured into a plurality of substantially pumpkin-shaped compartments when a first pressure inside the interior volume is greater than a second pressure of a surrounding atmosphere,
the plurality of substantially pumpkin-shaped compartments comprises a first substantially pumpkin-shaped compartment in fluid communication with a second substantially pumpkin-shaped compartment; and
the continuous, multi-compartment SPB comprises a constriction between the first substantially pumpkin-shaped compartment and the second substantially pumpkin-shaped compartment;
an elongated connector coupled with and extending downward from the SPB;
a payload support coupled with the SPB via the elongated connector and configured to support a payload;
a solar array coupled with and extending at least partially along the elongated connector;
a compressor in fluid communication with the interior volume of the SPB and configured to compress the ambient air and pump compressed ambient air into the interior volume of the SPB to increase the downward force to the balloon system; and
an air hose extending at least partially along the elongated connector and fluidly coupling the compressor with the interior volume of the SPB.
2. The balloon system of claim 1 , wherein the constriction comprises a rope ring.
3. The balloon system of claim 1 , wherein the constriction comprises a metal fitting.
4. The balloon system of claim 1 , wherein each of the plurality of substantially pumpkin-shaped compartments is configured to attain a maximum radius for a hoop stress of the outer skin.
5. The balloon system of claim 1 , further comprising:
a plurality of tendons extending along an exterior of the outer skin of the continuous, multi-compartment SPB,
the plurality of tendons configured to bias each of the plurality of compartments into the substantial pumpkin shape at least when the first pressure inside the interior volume is greater than the second pressure of the surrounding atmosphere.
6. The balloon system of claim 1 , wherein the continuous outer skin of the SPB comprises plastic, polymer, or a thin film.
7. The balloon system of claim 1 , wherein the elongated connector comprises a ladder assembly.
8. The balloon system of claim 1 , wherein the plurality of substantially pumpkin-shaped compartments further comprises:
a third substantially pumpkin-shaped compartment in fluid communication with the first substantially pumpkin-shaped compartment and the second substantially pumpkin-shaped compartment,
the third substantially pumpkin-shaped compartment adjacent the second substantially pumpkin-shaped compartment,
the continuous, multi-compartment SPB comprising a second constriction between the second substantially pumpkin-shaped compartment and the third substantially pumpkin-shaped compartment.
9. The balloon system of claim 8 , wherein the plurality of substantially pumpkin-shaped compartments further comprises:
a fourth substantially pumpkin-shaped compartment in fluid communication with the first substantially pumpkin-shaped compartment, the substantially pumpkin-shaped second compartment, and the third substantially pumpkin-shaped compartment,
the fourth substantially pumpkin-shaped compartment adjacent the third substantially pumpkin-shaped compartment,
the continuous, multi-compartment SPB comprising a third constriction between the third substantially pumpkin-shaped compartment and the fourth substantially pumpkin-shaped compartment.
10. The balloon system of claim 1 , wherein the continuous outer skin of the SPB comprises a plurality of gores.
11. The balloon system of claim 10 , further comprising:
a plurality of tendons extending along an exterior of the outer skin of the continuous, multi-compartment SPB;
the outer skin forming a plurality of bulges when the first pressure inside the interior volume is greater than the second pressure of the surrounding atmosphere,
wherein each of the plurality of tendons extends along a valley between adjacent bulges.
12. The balloon system of claim 1 , further comprising:
an adjustable valve in fluid communication with the interior volume of the SPB, the valve configured to be adjusted to release the compressed ambient air from the interior volume of the SPB to the surrounding atmosphere to decrease the downward force to the balloon system.
13. The balloon system of claim 12 , further comprising:
a sensor coupled with the balloon system and configured to detect an environmental attribute; and
a control system in communication with the sensor, with the compressor, and with the adjustable valve, the control system configured to control the compressor and the adjustable valve based at least on the detected environmental attribute to control the amount of compressed air inside the SPB to control an altitude of the balloon system.
14. The balloon system of claim 12 , wherein the adjustable valve is configured to release the compressed ambient air from the interior volume of the SPB to the surrounding atmosphere via the air hose.
15. The balloon system of claim 1 , further comprising:
the ZPB configured to receive therein a lighter-than-air (LTA) gas to provide an upward lifting force to the balloon system, wherein the continuous, multi-compartment SPB is configured to be suspended below the ZPB in flight;
the compressor comprises a multi-stage centrifugal compressor configured to pump the ambient air into the interior volume of the SPB, the compressor configured to provide, at altitudes above 50,000 feet, at least 500 liters of the ambient air per second to the interior volume of the SPB such that a resulting descent rate of the balloon system is at least 10,000 feet per hour; and
an adjustable valve configured to release the ambient air from the interior volume of the SPB to the surrounding atmosphere.
16. The balloon system of claim 15 , wherein the adjustable valve is configured to release the ambient air from the interior volume of the SPB to the surrounding atmosphere via the air hose.
17. A lighter than air (LTA) system, comprising:
a zero pressure balloon (ZPB);
a super pressure balloon (SPB) configured to couple with the ZPB, the SPB comprising an outer skin defining an interior volume of the SPB, the interior volume in fluid communication with ambient air of a surrounding atmosphere and configured to receive the ambient air into the interior volume of the SPB to increase a downward force to the balloon system and to emit the ambient air from the interior volume of the SPB to the surrounding atmosphere to decrease the downward force to the balloon system;
an elongated ladder coupled with the SPB;
a solar array coupled with and extending at least partially along the elongated ladder;
a compressor; and
an air hose extending at least partially along the elongated ladder and fluidly coupling the compressor with the interior volume of the SPB.
18. The LTA system of claim 17 , further comprising a constriction extending circumferentially along an exterior of the outer skin.
19. The LTA system of claim 17 , wherein the SPB comprises a first substantially pumpkin-shaped compartment and a second substantially pumpkin-shaped compartment.
20. The LTA system of claim 19 , further comprising:
a plurality of tendons extending along an exterior of the outer skin of the SPB,
the plurality of tendons configured to bias the first compartment and the second compartment into the substantial pumpkin shape at least when the first pressure inside the interior volume is greater than the second pressure of the surrounding atmosphere.
21. The LTA system of claim 20 , the outer skin forming a plurality of bulges when the first pressure inside the interior volume is greater than the second pressure of the surrounding atmosphere, wherein each of the plurality of tendons extends along a valley between adjacent bulges.
22. The LTA system of claim 17 , further comprising an adjustable valve configured to be adjusted to release the compressed ambient air from the interior volume of the SPB to the surrounding atmosphere to decrease the downward force to the balloon system.
23. The LTA system of claim 22 , wherein the adjustable valve is configured to be adjusted release the ambient air from the interior volume of the SPB to the surrounding atmosphere via the air hose.
24. The LTA system of claim 22 , further comprising:
a sensor coupled with the LTA system and configured to detect an environmental attribute; and
a control system in communication with the sensor, with the compressor, and with the adjustable valve, the control system configured to control the compressor and the adjustable valve based at least on the detected environmental attribute to control the amount of compressed air inside the SPB to control an altitude of the LTA system.