LOON LLC

The technology relates to real-time state estimation and sensor management. A method for real-time state estimation and sensor management may include receiving telemetry from a fleet of aerial vehicles, storing telemetry in a telemetry buffer, generating a real-time state estimate of an aerial vehicle in the fleet using a group of estimators, the estimators being of one or more types, such as a sensor management estimator, a bias and noise management estimator, and a physical modeling estimator, and providing the real-time state estimate of the aerial vehicle to a job in a fleet management system.

The technology relates to aerial vehicle launch and land site selection. A method for determining beneficial launch and land sites may include computing a launch delay for a desired time period for each cell in a grid map with a target zone and an existing site located on the grid map, computing a flight time to target for a delay time that accounts for a launch delay, computing a launch time to target based on the launch delay and the flight time to target, receiving geographical restrictions data, and determining an efficiency benefit over the existing site based on the geographical restrictions data and a comparison of the launch time to target of each cell with the launch time to target of the existing site for the desired time period.

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.

The technology relates to a storm avoidance system for a lighter than air (LTA) vehicle. The storm avoidance system can include a mechanical actuation system, a balloon envelope comprising a ballonet, and a valve configured to allow air to escape the ballonet. When the storm avoidance system is engaged, the mechanical actuation system can open the valve, thereby allowing air to escape the ballonet and causing the LTA vehicle to ascend to an altitude above a storm altitude. In some cases, a state of the LTA vehicle can be detected, and the storm avoidance system can be engaged in response to the detected state. In some cases, a proximity of the LTA to a low population area can be determined, and the LTA vehicle can be caused to land in the low population area.

Aspects of the technology relate to altitude control and lateral propulsion systems in lighter-than-air (LTA) platforms configured to operate in the stratosphere. For instance, an LTA platform may include an envelope filled with lift gas and a payload for providing telecommunication or video services. A fault or failure condition with one or more components of these systems, or with the envelope of the LTA platform itself, can prevent a high altitude platform (HAP) from operating as intended, or otherwise reduce its useful life. Onboard systems are configured to handle adverse conditions, such as a fault or failure of the envelope, an altitude control system component, or the lateral propulsion system. This may be done according to one or more ranked lists of adverse operational conditions. Different conditions may map to different corrective actions, which may be prioritized in importance, for instance to reduce the chance of catastrophic system failure.

Aspects of the technology relate to lighter-than-air (LTA) high altitude platforms configured to operate in the stratosphere. Such platforms can generate solar power from solar panels, enabling long-term operation for weeks, months or longer. Shaped envelope LTA platforms may have solar panels arranged along an upper section of the envelope, which can be particularly helpful when the envelope is made of a fabric that is not transparent or translucent. To address possible thermal effects, aerodynamics and other issues with the solar panels, one or more external air bladders are disposed between the such components and the shaped envelope. One or more perimeter chamber of the air bladder configuration can be employed to create more aerodynamically efficient leading and trailing edges to blend the envelope surface with the surface(s) of the solar panel components. The insulative air bladder(s) may also provide structural support during fill of a shaped envelope at launch.

The technology relates to techniques for an aquatic energy discharge system for an energy storage system of an aircraft. An aquatic energy discharge system can include an energy storage system, a pair of electrodes coupled to the energy storage system, and a water detection system configured to detect a water landing. The electrodes can be configured to submerge in a body of water after the aircraft has landed in the body of water, and cause a hydrolysis reaction that drains energy from the energy storage system in response to the water detection system detecting the water landing. A method of discharging an energy storage system of an aircraft can include detecting that an aircraft (or portion thereof) has landed in a body of water, and discharging the energy storage system by powering a hydrolysis reaction using a pair of electrodes.

The technology relates to techniques for redundant power distribution and monitoring for lighter than air (LTA) vehicles. A power distribution and monitoring system for an LTA vehicle, can include two or more redundant controllers coupled to a multiplexer in a crossbar architecture. Each controller can control the multiplexer and inhibit the other controller in the case of a failure of the other controller. Each controller can control a power switch to direct power from a power source to an electronic component, and can monitor the power source. In some cases, a first controller receives a signal indicting a failure in a second controller, and the first controller inhibits the second controller and directs power from the power source to the electronic component.

The technology relates to health and lifetime estimation for a lighter-than-air vehicle. A method for vehicle health and lifetime estimation may include receiving flight data inputs associated with a vehicle, determining a gas temperature based on the flight data inputs, estimating a gas amount remaining in a balloon envelope of the vehicle, estimating a gas leak rate based on the gas amount, estimating a component lifetime representing an estimated lifetime of a component of the vehicle, and determining a remaining lifetime output based on one or both of the gas leak rate or the component lifetime, the remaining lifetime output indicating a remaining lifetime estimate for the vehicle. The method also may include simulating a terminal event and causing the vehicle to take an action based on the remaining lifetime estimate.

The technology relates to health and lifetime estimation for a lighter-than-air vehicle. A method for vehicle health and lifetime estimation may include receiving flight data inputs associated with a vehicle, determining a gas temperature based on the flight data inputs, estimating a gas amount remaining in a balloon envelope of the vehicle, estimating a gas leak rate based on the gas amount, and determining a remaining lifetime output based on the gas leak rate, the remaining lifetime output indicating a remaining lifetime estimate for the vehicle. The method also may include simulating a terminal event and causing the vehicle to take an action based on the remaining lifetime estimate.