Abstract: The technology relates to a telescoping support structure which can be suspended between two objects. The telescoping support structure uses projections between adjacent tubular sections in order to prevent the adjacent tubular sections from falling away from one another. Although the telescoping support structure may be utilized in various different environments and circumstances, it may be of particular usefulness in the field of high-altitude ballooning. For instance, when used in a balloon system, the telescoping support structure may be suspended between two objects such as an upper payload structure and a lower payload structure. As another example, the telescoping support structure may be suspended between a balloon envelope and a payload which, in some examples, may include an upper and a lower payload structure.

Abstract: A system for an unmanned aerial vehicle can include an altitude control system 320, which further includes a compressor assembly 400, a valve assembly 500, and an electronics control assembly 600. The compressor assembly may include a compressor housing 410 that includes a compressor inlet 402, an outlet 202, and a cavity 414 extending therethrough and joining the inlet to the outlet. A diffuser 408 may be coupled to the compressor housing. A motor housing 407 may be disposed within the central cavity at the inlet of the compressor housing, and a compressor motor 406 may be disposed within the motor housing. An impeller 412 disposed within the compressor housing may be coupled to a driveshaft 444 for rotation therewith. The valve assembly may be coupled to an opening 416 of the compressor inlet. The valve head 502 may be configured to move into and away from the inlet opening so as to change a size of the circumferential area of the inlet opening.

Abstract: Aspects of the disclosure provide a flex connection for high altitude balloon applications. During operation flex connection allows a payload of a high-altitude balloon to remain level when an envelope of the balloon is tilted, in order to change the direction of the balloon. As an example, a system may include a balloon envelope, a payload, a cable between the balloon envelope and the payload, and a flex connection on the cable. The flex connection enables the payload to remain level relative to the ground when the balloon is in flight and the balloon envelope is tilted relative to the payload. The flex connection includes a top portion, a plurality of discs, and a bottom portion.

Abstract: A stratospheric balloon may include an upper structure having a pulley, a lower structure, at least one solar panel suspended between the upper structure and the lower structure, and a first orientation control member connected, at a first end thereof, to a first transverse edge of the at least one solar panel and, at a second end thereof, to a second transverse edge of the at least one solar panel. The first orientation control member is wound about the pulley such that rotating the pulley changes the orientation of the at least one solar panel relative to the upper structure and the lower structure. In another example, the pulley may be replaced by first and second support mechanisms and the system may include a second orientation control member. The first and second orientation control members are connected to the first and second support mechanisms, respectively, and to the solar panel.

Abstract: A system for an unmanned aerial vehicle can include an altitude control system 320, which further includes a compressor assembly 400, a valve assembly 500, and an electronics control assembly 600. The compressor assembly may include a compressor housing 410 that includes a compressor inlet 402, an outlet 202, and a cavity 414 extending therethrough and joining the inlet to the outlet. A diffuser 408 may be coupled to the compressor housing. A motor housing 407 may be disposed within the central cavity at the inlet of the compressor housing, and a compressor motor 406 may be disposed within the motor housing. An impeller 412 disposed within the compressor housing may be coupled to a driveshaft 444 for rotation therewith. The valve assembly may be coupled to an opening 416 of the compressor inlet. The valve head 502 may be configured to move into and away from the inlet opening so as to change a size of the circumferential area of the inlet opening.

Abstract: Aspects of the technology relate to a propeller blade assembly that is used in lateral propulsion systems for lighter-than-air high altitude platforms designed to operate, e.g., in the stratosphere. During operation, the propeller of the assembly is pointed along a specified heading and rotates at a selected velocity (e.g., hundreds or thousands of revolutions per minute). Power is supplied to the propeller as needed during lateral propulsion to move the platform along a particular trajectory or to remain on station over a given geographic location. In certain circumstances, the propeller may become damaged. This can include one or more blades breaking or shattering, which can result in failure of the propeller and potentially the entire LTA platform. The technology provides blades that are sufficiently flexible to avoid breakage or shattering due to debris impact or envelope entanglement, or otherwise shed a load. This can avoid catastrophic failure during stratospheric operation.

Abstract: Aspects of the disclosure relate to high altitude or stratospheric balloon systems. For instance, a stratospheric balloon system may include a an upper structure, a lower structure, a platform associated with the lower structure, a stack of solar panels positioned on the platform, each solar panel coupled to an adjacent solar panel, at least one tension element connected, at a first end thereof, to the upper structure and, at a second end thereof, to the platform, and a first flexible tension member coupled, at a first end thereof, to the upper structure and to foremost solar panel of the stack of solar panels. Solar panels may be stacked in a “Z-fold” configuration with either solar cells of the adjacent solar panels facing one another or the frames of the adjacent solar panels facing one another. In this configuration, the adjacent solar panels are connected by a hinge system.

Abstract: Aspects of the technology relate to a propeller blade assembly that is used in lateral propulsion systems for lighter-than-air high altitude platforms designed to operate, e.g., in the stratosphere. During operation, the propeller of the assembly is pointed along a specified heading and rotates at a selected velocity (e.g., hundreds or thousands of revolutions per minute). Power is supplied to the propeller as needed during lateral propulsion to move the platform along a particular trajectory or to remain on station over a given geographic location. In certain circumstances, the propeller may become damaged. This can include one or more blades breaking or shattering, which can result in failure of the propeller and potentially the entire LTA platform. The technology provides blades that are sufficiently flexible to avoid breakage or shattering due to debris impact or envelope entanglement, or otherwise shed a load. This can avoid catastrophic failure during stratospheric operation.

Abstract: The technology relates to techniques for lightweight brackets for storm hardening of aircraft components. A bracket flange for protecting an electronics assembly from electrical storm activity can include a leg element coupled to and extending from a component of a vehicle and a first bar element extending from another end of the leg element on a plane substantially parallel to the component and over a part of an electronics assembly. The location of the bracket flange can be determined using a lightning attachment survey configured to indicate a part of the electronics assembly to which a lightning streamer attaches during an electrical surge. The location and size of the bracket flange may be configured to divert surge current away from the part of the electronics assembly to which the lightning streamer attaches in the lightning attachment survey.

Abstract: Aspects of the disclosure relate to a mechanical fuse having a first component having an opening in a lower wall and a ledge arranged around the opening and a second component having a top surface with a threaded opening arranged therein. The top surface of the second component may be oriented towards the first component such that the top surface is arranged entirely below the lower wall in order to enable the first component and the second component to pivot relative to one another at the bolt. The mechanical fuse may also include a bolt having a neck including a reduced cross-sectional area portion, and the bolt is configured to break and separate the first component from the second component when a predetermined amount of force is transmitted from the first component to the reduced cross-sectional area portion via the pivoting.

Abstract: Aspects of the disclosure relate to flight termination systems for aerial vehicles having envelopes. For instance, a flight termination system may include one or more heat sources mounted on the top plate and oriented towards envelope material of the envelope. The one or more heat sources may each include a gas generator configured to generate gas of sufficient temperature to melt the envelope material and vent lift gas from the envelope. The flight termination system may also include a drag device arranged at the top plate which may be being configured to provide stability to the envelope during descent.

Abstract: Aspects of the disclosure relate to high altitude or stratospheric balloon systems. For instance, a stratospheric balloon system may include a an upper structure, a lower structure, a platform associated with the lower structure, a stack of solar panels positioned on the platform, each solar panel coupled to an adjacent solar panel, at least one tension element connected, at a first end thereof, to the upper structure and, at a second end thereof, to the platform, and a first flexible tension member coupled, at a first end thereof, to the upper structure and to foremost solar panel of the stack of solar panels. Solar panels may be stacked in a “Z-fold” configuration with either solar cells of the adjacent solar panels facing one another or the frames of the adjacent solar panels facing one another. In this configuration, the adjacent solar panels are connected by a hinge system.

Abstract: Aspects of the technology relate to propulsion systems for high altitude, long duration balloons, such as balloons that operate in the stratosphere for weeks, months or longer. A propeller assembly is used to provide lateral directional adjustments, which allows the balloon to spend more time over a desired region, reduce the return time to the desired region, reduce fleet overprovisioning, and increases the safety case by additional controls and avoidance abilities. A control assembly manages operation of the propeller assembly, including setting the pointing direction, speed of rotation and determining when to turn on the propeller and for how long. The propulsion system including the control and propeller assemblies is rotatable around a connection member of the balloon. Such rotation is independently adjustable from any rotation of the balloon's payload. The propeller blades may be made of plastic, which reduces weight and cost while providing sufficient speed at stratospheric altitudes.

Abstract: A stratospheric balloon may include an upper structure having a pulley, a lower structure, at least one solar panel suspended between the upper structure and the lower structure, and a first orientation control member connected, at a first end thereof, to a first transverse edge of the at least one solar panel and, at a second end thereof, to a second transverse edge of the at least one solar panel. The first orientation control member is wound about the pulley such that rotating the pulley changes the orientation of the at least one solar panel relative to the upper structure and the lower structure. In another example, the pulley may be replaced by first and second support mechanisms and the system may include a second orientation control member. The first and second orientation control members are connected to the first and second support mechanisms, respectively, and to the solar panel.

Abstract: A stratospheric balloon may include an upper structure having a pulley, a lower structure, at least one solar panel suspended between the upper structure and the lower structure, and a first orientation control member connected, at a first end thereof, to a first transverse edge of the at least one solar panel and, at a second end thereof, to a second transverse edge of the at least one solar panel. The first orientation control member is wound about the pulley such that rotating the pulley changes the orientation of the at least one solar panel relative to the upper structure and the lower structure. In another example, the pulley may be replaced by first and second support mechanisms and the system may include a second orientation control member. The first and second orientation control members are connected to the first and second support mechanisms, respectively, and to the solar panel.

Abstract: The technology relates to a telescoping support structure which can be suspended between two objects. The telescoping support structure uses projections between adjacent tubular sections in order to prevent the adjacent tubular sections from falling away from one another. Although the telescoping support structure may be utilized in various different environments and circumstances, it may be of particular usefulness in the field of high-altitude ballooning. For instance, when used in a balloon system, the telescoping support structure may be suspended between two objects such as an upper payload structure and a lower payload structure. As another example, the telescoping support structure may be suspended between a balloon envelope and a payload which, in some examples, may include an upper and a lower payload structure.

Abstract: Aspects of the disclosure provide anti-tilt assemblies for reducing the strain of an air ballast when used to change the direction of a high altitude balloon. For instance, in one example, a balloon includes a balloon envelope having an air ballast and a plurality of support tendons and a payload assembly. The balloon also includes an anti-tilt assembly arranged between the balloon envelope and the payload assembly. The anti-tilt assembly includes a support structure having a plurality of line connections arranged at a top end of the support structure and a connection member at a bottom end of the support structure. The connection member is attached to the payload assembly. The anti-tilt assembly also includes a plurality of support lines connected at to one of the support tendons and to the connection member. In addition, each support line is arranged to pass through a corresponding one of the line connections.

Abstract: The technology relates to a telescoping support structure which can be suspended between two objects. The telescoping support structure uses projections between adjacent tubular sections in order to prevent the adjacent tubular sections from falling away from one another. Although the telescoping support structure may be utilized in various different environments and circumstances, it may be of particular usefulness in the field of high-altitude ballooning. For instance, when used in a balloon system, the telescoping support structure may be suspended between two objects such as an upper payload structure and a lower payload structure. As another example, the telescoping support structure may be suspended between a balloon envelope and a payload which, in some examples, may include an upper and a lower payload structure.

Abstract: Aspects of the disclosure provide a flex connection for high altitude balloon applications. During operation flex connection allows a payload of a high-altitude balloon to remain level when an envelope of the balloon is tilted, in order to change the direction of the balloon. As an example, a system may include a balloon envelope, a payload, a cable between the balloon envelope and the payload, and a flex connection on the cable. The flex connection enables the payload to remain level relative to the ground when the balloon is in flight and the balloon envelope is tilted relative to the payload. The flex connection includes a top portion, a plurality of discs, and a bottom portion.

Abstract: A system for an unmanned aerial vehicle can include an altitude control system 320, which further includes a compressor assembly 400, a valve assembly 500, and an electronics control assembly 600. The compressor assembly may include a compressor housing 410 that includes a compressor inlet 402, an outlet 202, and a cavity 414 extending therethrough and joining the inlet to the outlet. A diffuser 408 may be coupled to the compressor housing. A motor housing 407 may be disposed within the central cavity at the inlet of the compressor housing, and a compressor motor 406 may be disposed within the motor housing. An impeller 412 disposed within the compressor housing may be coupled to a driveshaft 444 for rotation therewith. The valve assembly may be coupled to an opening 416 of the compressor inlet. The valve head 502 may be configured to move into and away from the inlet opening so as to change a size of the circumferential area of the inlet opening.