Abstract: Aspects of the technology relate to rotational electromechanical systems, in which data and or power are supplied to components while one part of the system is rotating relative to another part of the system. Repeated rotation may create strain on or otherwise cause the cables to intermittently or permanently fail. A helical cable management system is provided that enables full rotation to the extent permitted. One or more cables are wound in a helical shape around the axis of rotation, which distributes the deformation of the cable along the helical length. Rotation in one direction causes the helix diameter to increase, while rotation in the other direction causes the helix diameter to decrease. A structure is used to maintain the distance between helical turns, while permitting the increase and decrease of the helix diameter. This reduces the overall strain on the cables, which can significantly extend their useful lifetime.

Abstract: Aspects of the technology relate to a braking assembly for a lateral propulsion system of a high altitude platform (HAP) configured to operate in the stratosphere. Power is supplied to a propeller assembly as needed during lateral propulsion so that the HAP can move to a desired location or remain on station. When lateral propulsion is not needed, power is no longer supplied to the propeller assembly and it may slowly cease rotating. However, in certain situations, it may be necessary to cause the propeller assembly to stop rotating as soon as possible. This can include an unplanned descent. Rapid braking can avoid the propeller blades from entangling in the envelope, parachute or other parts of the HAP. A reusable brake is employed to prevent uncontrolled rotation of the propeller on descent, or otherwise to prevent the propeller from spinning freely when not being used to propel the HAP laterally.

Abstract: Aspects of the technology relate to rotational electromechanical systems, in which data and or power are supplied to components while one part of the system is rotating relative to another part of the system. Repeated rotation may create strain on or otherwise cause the cables to intermittently or permanently fail. A helical cable management system is provided that enables full rotation to the extent permitted. One or more cables are wound in a helical shape around the axis of rotation, which distributes the deformation of the cable along the helical length. Rotation in one direction causes the helix diameter to increase, while rotation in the other direction causes the helix diameter to decrease. A structure is used to maintain the distance between helical turns, while permitting the increase and decrease of the helix diameter. This reduces the overall strain on the cables, which can significantly extend their useful lifetime.

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 technology relate to a braking assembly for a lateral propulsion system of a high altitude platform (HAP) configured to operate in the stratosphere. Power is supplied to a propeller assembly as needed during lateral propulsion so that the HAP can move to a desired location or remain on station. When lateral propulsion is not needed, power is no longer supplied to the propeller assembly and it may slowly cease rotating. However, in certain situations, it may be necessary to cause the propeller assembly to stop rotating as soon as possible. This can include an unplanned descent. Rapid braking can avoid the propeller blades from entangling in the envelope, parachute or other parts of the HAP. A reusable brake is employed to prevent uncontrolled rotation of the propeller on descent, or otherwise to prevent the propeller from spinning freely when not being used to propel the HAP laterally.

Abstract: Aspects of the technology relate to lighter-than-air (LTA) high altitude platforms configured to operate in the stratosphere. Such platforms can generate operate for weeks, months or longer. Shaped envelope LTA platforms may support a payload that provides telecommunications and/or other services to remote regions around the world. The payload may be arranged with other components on a modular bus-type chassis. One or more components may be moveable along the chassis to change the pitch of the vehicle for more effective flight operation. The modular chassis may include a truss configuration assembled from one or more subunits. The subunits may be preassembled with different equipment packages. Trusses formed using sets of struts may have two or more struts terminating at one interconnection node. Node connection elements, such as compound dovetail interconnects, facilitate a reliable, repeatable and quick mounting method for structural interconnections, which can lead to faster assembly and disassembly times.

Abstract: Aspects of the technology relate to rotational electromechanical systems, in which data and or power are supplied to components while one part of the system is rotating relative to another part of the system. Repeated rotation may create strain on or otherwise cause the cables to intermittently or permanently fail. A helical cable management system is provided that enables full rotation to the extent permitted. One or more cables are wound in a helical shape around the axis of rotation, which distributes the deformation of the cable along the helical length. Rotation in one direction causes the helix diameter to increase, while rotation in the other direction causes the helix diameter to decrease. A structure is used to maintain the distance between helical turns, while permitting the increase and decrease of the helix diameter. This reduces the overall strain on the cables, which can significantly extend their useful lifetime.

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 technology relate to a braking assembly for a lateral propulsion system of a high altitude platform (HAP) configured to operate in the stratosphere. Power is supplied to a propeller assembly as needed during lateral propulsion so that the HAP can move to a desired location or remain on station. When lateral propulsion is not needed, power is no longer supplied to the propeller assembly and it may slowly cease rotating. However, in certain situations, it may be necessary to cause the propeller assembly to stop rotating as soon as possible. This can include an unplanned descent. Rapid braking can avoid the propeller blades from entangling in the envelope, parachute or other parts of the HAP. A reusable brake is employed to prevent uncontrolled rotation of the propeller on descent, or otherwise to prevent the propeller from spinning freely when not being used to propel the HAP laterally.

Abstract: Aspects of the technology relate to a braking assembly for a lateral propulsion system of a high altitude platform (HAP) configured to operate in the stratosphere. Power is supplied to a propeller assembly as needed during lateral propulsion so that the HAP can move to a desired location or remain on station. When lateral propulsion is not needed, power is no longer supplied to the propeller assembly and it may slowly cease rotating. However, in certain situations, it may be necessary to cause the propeller assembly to stop rotating as soon as possible. This can include an unplanned descent. Rapid braking can avoid the propeller blades from entangling in the envelope, parachute or other parts of the HAP. A reusable brake is employed to prevent uncontrolled rotation of the propeller on descent, or otherwise to prevent the propeller from spinning freely when not being used to propel the HAP laterally.

Abstract: Aspects of the technology relate to rotational electromechanical systems, in which data and or power are supplied to components while one part of the system is rotating relative to another part of the system. Repeated rotation may create strain on or otherwise cause the cables to intermittently or permanently fail. A helical cable management system is provided that enables full rotation to the extent permitted. One or more cables are wound in a helical shape around the axis of rotation, which distributes the deformation of the cable along the helical length. Rotation in one direction causes the helix diameter to increase, while rotation in the other direction causes the helix diameter to decrease. A structure is used to maintain the distance between helical turns, while permitting the increase and decrease of the helix diameter. This reduces the overall strain on the cables, which can significantly extend their useful lifetime.

Abstract: Aspects of the technology relate to rotational electromechanical systems, in which data and or power are supplied to components while one part of the system is rotating relative to another part of the system. Repeated rotation may create strain on or otherwise cause the cables to intermittently or permanently fail. A helical cable management system is provided that enables full rotation to the extent permitted. One or more cables are wound in a helical shape around the axis of rotation, which distributes the deformation of the cable along the helical length. Rotation in one direction causes the helix diameter to increase, while rotation in the other direction causes the helix diameter to decrease. A structure is used to maintain the distance between helical turns, while permitting the increase and decrease of the helix diameter. This reduces the overall strain on the cables, which can significantly extend their useful lifetime.

Abstract: An antenna reflector includes a laminated structure including a first layer and a second layer, where the first layer has an electrically conductive and electrically reflective front surface and includes a nonwoven metallized fiber matte and the second layer includes an open weave fabric. The laminated structure is acoustically permeable. In some implementations, a laminated structure is formed by co-curing the first layer and the second layer.