Abstract:
Methods and systems for reverse-iterating a backward planner determining trajectories for vehicles of a fleet of vehicles are provided. In one example an iterator configured for recursively determining the contingency tables at successive time steps in a computational iteration order from a target time to an initial time is caused to reverse-generate the contingency tables in an order from the initial time to the target time. Reverse-generation is caused by recursively: (i) subdividing a sequence of time steps by a factor of at least two into successively smaller sub-sequences, (ii) iterating in a computational iteration order over each recursively subdivided sub-sequence, and (iii) generating a contingency table closest in time to the initial time for the recursive iteration over each recursively subdivided sub-sequence.
Abstract:
Methods and systems for determining trajectories for vehicles of a fleet of vehicles are provided. In one example, a method comprises receiving an initial location of one or more vehicles, and receiving a sequence of coverage requirements for a region and an associated period of time. The region may be divided into a plurality of landmarks and the period of time may be divided into a plurality of phases. The method also comprises determining for each of one or more phases and at least one respective landmark, a set of starting landmarks from which a vehicle could reach the respective landmark during the phase. The method further comprises determining which respective landmark that the vehicle should travel to during the one or more phases based on the sequence of coverage requirements and the set of starting landmarks for the one or more phases and the at least one respective landmark.
Abstract:
Methods and systems for determining trajectories for vehicles of a fleet of vehicles are provided. In one example, a method comprises receiving an initial location of one or more vehicles, and receiving a sequence of coverage requirements for a region and an associated period of time. The region may be divided into a plurality of landmarks and the period of time may be divided into a plurality of phases. The method also comprises determining for each of one or more phases and at least one respective landmark, a set of starting landmarks from which a vehicle could reach the respective landmark during the phase. The method further comprises determining which respective landmark that the vehicle should travel to during the one or more phases based on the sequence of coverage requirements and the set of starting landmarks for the one or more phases and the at least one respective landmark.
Abstract:
Methods and systems for determining trajectories for vehicles of a fleet of vehicles are provided. In one example, a method comprises receiving an initial location of one or more vehicles, and receiving a sequence of coverage requirements for a region and an associated period of time. The region may be divided into a plurality of landmarks and the period of time may be divided into a plurality of phases. The method also comprises determining for each of one or more phases and at least one respective landmark, a set of starting landmarks from which a vehicle could reach the respective landmark during the phase. The method further comprises determining which respective landmark that the vehicle should travel to during the one or more phases based on the sequence of coverage requirements and the set of starting landmarks for the one or more phases and the at least one respective landmark.
Abstract:
Methods and systems for determining trajectories for vehicles of a fleet of vehicles are provided. In one example, a method comprises receiving an initial location of one or more vehicles, and receiving a sequence of coverage requirements for a region and an associated period of time. The region may be divided into a plurality of landmarks and the period of time may be divided into a plurality of phases. The method also comprises determining for each of one or more phases and at least one respective landmark, a set of starting landmarks from which a vehicle could reach the respective landmark during the phase. The method further comprises determining which respective landmark that the vehicle should travel to during the one or more phases based on the sequence of coverage requirements and the set of starting landmarks for the one or more phases and the at least one respective landmark.
Abstract:
This disclosure relates to the use of an optimal altitude controller for super pressure aerostatic balloon in connection with a balloon network. The aerostatic balloon includes a bladder containing a gas that is lighter than the air present in the environment of the balloon. Additionally, the aerostatic balloon includes an envelope filled with air. A mass-changing unit configured to selectively add or remove air may control the amount of air in the envelope. Further, the balloon has a communication module configured to transmit data relating to a current balloon state, and receives data relating to a desired balloon state. Additionally, the balloon includes a processor configured to control the mass-changing unit based on the desired balloon state. The mass-changing unit of the aerostatic balloon may be powered by a renewable energy source, such as solar power. The mass-changing unit adds or removes air with an impeller.
Abstract:
Methods and systems for determining trajectories for a fleet of vehicles are provided. In one example, a method comprises receiving an initial location of one or more vehicles, and receiving a sequence of coverage requirements for a region and an associated period of time. The method also comprises determining, for each of one or more phases, single-phase landmarks that a vehicle could travel to over the duration of the phase, and determining for at least one of the one or more phases, phase-skipping landmarks that a vehicle could travel to over the duration of multiple phases. The method further comprises determining which landmarks of the single-phase landmarks and phase-skipping landmarks that a vehicle should travel to based on the initial locations of the one or more vehicles and the sequence of coverage requirements.
Abstract:
This disclosure relates to the use of an optimal altitude controller for super pressure aerostatic balloon in connection with a balloon network. The aerostatic balloon includes a bladder containing a gas that is lighter than the air present in the environment of the balloon. Additionally, the aerostatic balloon includes an envelope filled with air. A mass-changing unit configured to selectively add or remove air may control the amount of air in the envelope. Further, the balloon has a communication module configured to transmit data relating to a current balloon state, and receives data relating to a desired balloon state. Additionally, the balloon includes a processor configured to control the mass-changing unit based on the desired balloon state. The mass-changing unit of the aerostatic balloon may be powered by a renewable energy source, such as solar power. The mass-changing unit adds or removes air with an impeller.
Abstract:
This disclosure relates to the use of a method for determining communication timing of an aerial vehicle, such as a balloon. The method includes determining a trajectory of an aerial vehicle. Additionally, the method includes, based on the trajectory, determining a transmission trigger for a location-report message such that a location-report message transmission that is responsive to the transmission trigger has at least a predefined probability of occurring before the aerial vehicle contacts the ground. Further, the method also includes, responsive to the transmission trigger, transmitting the location-report message, where the location-report message comprises location data from the aerial vehicle.
Abstract:
Methods and systems for determining a cyclical pattern of trajectories for a fleet of vehicles are provided. In one example, a method comprises receiving a sequence of coverage requirements for a region and an associated period of time. For each of one or more phases of the period of time, possible routes that a vehicle located at one or more respective landmarks at a beginning of the phase could follow to reach one or more additional landmarks by an end of the phase are determined. Further, a cyclical pattern of trajectories for vehicles of a fleet of vehicles that minimizes a difference between a distribution of the fleet at a beginning of the period of time and a distribution of the fleet at an end of the period of time is determined.