Lighter-than-air platform

Abstract

Techniques are disclosed relating lighter-than-air aircraft. Such aircraft may be used for various purposes, such as providing network connectivity to areas that would otherwise lack such connectivity. For example, in some embodiments, a lighter-than-air aircraft according to this disclosure may include various types of antennas (directional or non-directional) for communicating with ground-based electronics or with other lighter-than-air aircraft.

1 . An apparatus, comprising:
 an outer membrane;   a flexible bladder within the outer membrane;   a region disposed inside the outer membrane and outside the flexible bladder; and   a pressure adjustment device configured to adjust a particular pressure within the apparatus;   wherein the apparatus is configured to float at a selected altitude based on a quantity of lighter-than-air gas in the flexible bladder; and   wherein the pressure adjustment device is configured to reduce leakage of the lighter-than-air gas from the flexible bladder by adjusting the particular pressure within the apparatus such that a pressure inside the flexible bladder is equalized with a pressure in the region.   
     
     
         2 . The apparatus of  claim 1 , wherein a volume detection device is configured to measure a volume of the flexible bladder within the outer membrane, and the pressure adjustment device is configured to reduce leakage of the lighter-than-air gas from the flexible bladder by adjusting, based on measurements from the volume detection device, the particular pressure within the apparatus such that the volume of the flexible bladder is maintained at a desired volume less than its maximum volume, thereby equalizing the pressure inside the flexible bladder with the pressure in the region. 
     
     
         3 . The apparatus of  claim 1 , wherein the particular pressure is the pressure inside the flexible bladder. 
     
     
         4 . The apparatus of  claim 1 , wherein the particular pressure is the pressure in the region. 
     
     
         5 . The apparatus of  claim 1 , wherein the region is filled with a gas other than the lighter-than-air gas. 
     
     
         6 . The apparatus of  claim 5 , wherein the gas other than the lighter-than-air gas is air. 
     
     
         7 . The apparatus of  claim 1 , further comprising at least one solar panel configured to provide electrical power to the apparatus. 
     
     
         8 . The apparatus of  claim 1 , further comprising at least one propeller configured to maintain the apparatus in a selected geodetic location. 
     
     
         9 . The apparatus of  claim 1 , wherein the selected altitude is at least 60,000 feet above sea level. 
     
     
         10 . The apparatus of  claim 1 , wherein the flexible bladder comprises a plurality of flexible bladders. 
     
     
         11 . The apparatus of  claim 1 , further comprising at least one antenna configured to provide telecommunications service to land disposed beneath the apparatus. 
     
     
         12 . A method comprising:
 providing an unmanned, lighter-than-air aircraft that includes:
 an outer membrane; 
 a flexible bladder within the outer membrane; 
 a region disposed inside the outer membrane and outside the flexible bladder; and 
 a pressure adjustment device configured to adjust a particular pressure within the aircraft; 
   causing the aircraft to float at a selected altitude based on a quantity of lighter-than-air gas in the flexible bladder; and   reducing leakage of the lighter-than-air gas from the flexible bladder by adjusting the particular pressure within the aircraft such that a pressure inside the flexible bladder is equalized with a pressure in the region.   
     
     
         13 . The method of  claim 12 , wherein a volume of the flexible bladder is measured by a volume detection device within the outer membrane, and the pressure adjustment device reduces leakage of the lighter-than-air gas from the flexible bladder by adjusting, based on measurements from the volume detection device, the particular pressure within the aircraft such that the volume of the flexible bladder is maintained at a desired volume less than its maximum volume, thereby equalizing the pressure inside the flexible bladder with the pressure in the region. 
     
     
         14 . The method of  claim 13 , wherein the volume detection device comprises:
 a lever arm;   a tension element configured to press the lever arm against a surface of the flexible bladder; and   a potentiometer configured, based on a position of the lever arm, to measure the volume of the flexible bladder.   
     
     
         15 . The method of  claim 13 , wherein the volume detection device comprises an electromagnetic measurement device configured to:
 send electromagnetic radiation to a surface of the flexible bladder; and   based on a delay time associated with a reflection of the electromagnetic radiation, determine a distance to the flexible bladder; and   based on the determined distance, determine the volume of the flexible bladder.   
     
     
         16 . The method of  claim 15 , wherein the electromagnetic radiation is an optical pulse. 
     
     
         17 . The method of  claim 15 , wherein the electromagnetic radiation is a laser pulse. 
     
     
         18 . The method of  claim 12 , wherein the lighter-than-air gas comprises hydrogen gas. 
     
     
         19 . The method of  claim 12 , wherein the particular pressure is the pressure inside the flexible bladder. 
     
     
         20 . The method of  claim 12 , wherein the particular pressure is the pressure in the region.