An unmanned aerial vehicle (UAV) landing method includes detecting, via one or more visual sensors, a gesture or movement of an operator of a UAV; and controlling to decelerate, with aid of one or more processors and in response to the detected gesture or movement, one or more rotor blades of the UAV to cause the UAV to land autonomously.

A multi-rotor aerial vehicle comprises at least two rotors, a controller, a power supply having an output shaft, a shaft-driven hydraulic machine coupled to the output shaft and at least two rotor-driving hydraulic machines coupled to respective rotors. At least one of the hydraulic machines is an electronically commutated hydraulic machine in which displacement of hydraulic fluid through each working chamber is regulated by electronically controllable valves, during each cycle of working chamber volume, in phased relationship to cycles of working chamber volume. The controller controls the electronically controllable valves of the electronically commutated hydraulic machines to independently control the rotation of the rotors. The shaft-driven hydraulic machine may be an electronically commutated machine with a plurality of independent outputs, which independently drive the rotor-driving hydraulic machines. The rotor-driving hydraulic machines may be electronically commutated machines the displacement of which is independently controlled to independently drive the rotors.

The present application provides methods and systems for launching an unmanned aerial vehicle (UAV). An exemplary system for launching a UAV includes a detector configured to detect acceleration of the UAV in a launch mode. The exemplary system may also include a memory storing instructions and a processor configured to execute the instructions to cause the system to: obtain a signal configured to notify the UAV to enter the launch mode, determine whether the acceleration of the UAV satisfies a condition corresponding to threshold acceleration in the launch mode, and responsive to the determination that the acceleration of the UAV satisfies the condition, turn on a motor of the UAV.

A robot including a hybrid fan-based and fluid-based propulsion system to provide thrust, such as deceleration during fall to create a smooth landing or to provide a quick reduction in velocity, and to provide actuation/controlled motion, such as to hover after quick deceleration and to control orientation or pose. The hybrid propulsion system uses discharging of pressurized fluid and exhausted gas (or fluid in some cases) from ducted fans (or propellers, impellers, and the like) to provide controlled thrust and/or lift forces. The hybrid propulsion system uses of pressurized fluid for generating larger or primary thrust and quick changes in velocity. The hybrid propulsion system includes a fan-based propulsion assembly with ducted fans that use environmental air (or fluids) to provide lower or secondary thrust. Both types of propulsion can be integrated into a robot or robotic figure to move the robot during flight (e.g., during falling or hovering).

The technology relates to service dispatchers for fleet management and flight planning systems. A method for dispatching vehicles for service includes receiving, by a service dispatcher, a first input comprising a plurality of state data of a fleet of aerial vehicles and a second input comprising a service objective; determining, using the first input, that one or more aerial vehicles in the fleet meets a set of criteria associated with performing the service objective; submitting a bid on the one or more aerial vehicles, the bid configured to induce a vehicle allocator to allocate the one or more aerial vehicles to the service dispatcher; receiving an allocation of some or all of the one or more aerial vehicles; generating a plan to use the allocation to perform the service objective; and dispatching the allocation according to the plan.

A hydraulic propulsion system is disclosed. The system includes one or more input interfaces configured to receive mechanical power from a power source, four or more variable displacement pumps coupled to the one or more input interfaces adaptable to generate a controlled variable quantity of fluid to be pumped out of each of the variable displacement pumps in response to a control input from a corresponding control interface, and four or more positive displacement motors each fluidly coupled to a corresponding variable displacement pump and configured to receive the pumped fluid, wherein each motor is configured to be mechanically coupled to one or more aerodynamic rotors of a multi-rotor vertical take-off and landing aircraft to control thrust and attitude.

In one embodiment there is provided a flying toy that can be manually pumped with air. The pressurized air is kept in a canister and use to drive a propeller to propeller the toy for flight.

A system and method for the transfer of cryogenic fluid fuel includes a nozzle positionable with respect to fuel tank inlet, e.g., of an unmanned aerial vehicle (UAV), a seal to seal the area where the nozzle and inlet are connected, a collapsible and expandable bellows providing an isolation volume where the fluid is transferred from the nozzle into the inlet; a vacuum is provided in the volume to avoid accumulation of fuel or other species in the volume.

An unmanned aerial vehicle (UAV) landing method includes detecting, via one or more sensors on-board the UAV, a positional change of the UAV while the UAV is airborne; and generating, with aid of one or more processors on-board the UAV and in response to the detected positional change, one or more command signals to decelerate one or more rotor blades of the UAV, thereby causing the UAV to land autonomously.

A system and method for the transfer of cryogenic fluid fuel includes a nozzle positionable with respect to fuel tank inlet, e.g., of an unmanned aerial vehicle (UAV), a seal to seal the area where the nozzle and inlet are connected, a collapsible and expandable bellows providing an isolation volume where the fluid is transferred from the nozzle into the inlet; a vacuum is provided in the volume to avoid accumulation of fuel or other species in the volume.