Abstract: A takeoff location and a landing location are received for an autonomous vertical takeoff and landing (VTOL) vehicle that includes a plurality of rotors. An autonomous and noise-reduced flight trajectory for the autonomous VTOL vehicle is determined based at least in part on the takeoff location, the landing location, a jerk function, and a noise function, including by minimizing the jerk function and minimizing the noise function. A set of one or more desired forces or moments is determined for the autonomous VTOL vehicle based at least in part on autonomous and noise-reduced flight trajectory. A plurality of motor control signals is determined for the plurality of rotors based at least in part on the set of one or more desired forces or moments.

Abstract: Boundary information associated with a three-dimensional (3D) flying space is obtained, including a boundary of the 3D flying space. Location information associated with an aircraft is obtained, including a location of the aircraft. Information is presented based at least in part on the boundary information associated with the 3D flying space and the location information associated with the aircraft, including by presenting, in a display, the boundary of the 3D flying space and an avatar representing the aircraft at the location of the aircraft.

Abstract: Sensor data that includes or more of the following: (1) aircraft state information associated with an aircraft or (2) parachute canopy state information associated with a parachute canopy is received. The parachute canopy is coupled to the aircraft at a point aft of a center of mass of the aircraft. It is determined, based at least in part on the sensor data, whether to generate a control signal associated with maneuvering the aircraft into a nose-up position. A recovery action is performed, including by deploying the parachute canopy; wherein a load on the parachute canopy is reduced in the event the aircraft is in the nose-up position compared to the aircraft being in a nose-down position.

Abstract: A plurality of propellers generate vertical thrust at least some of the time. An attachment sub-system detachably couples to a vertical connector, where a plurality of vertically-stacked multicopters are configured to detachably couple to the vertical connector in order to transport a load at a bottom end of the vertical connector. There is an opening in a vehicle frame that is configured to: (1) receive the vertical connector prior to the attachment sub-system detachably coupling to the vertical connector and (2) hold the vertical connector while the attachment sub-system is detachably coupled to the vertical connector.

Abstract: A multi-modal aircraft recovery system is disclosed. In various embodiments, the system includes a first aircraft recovery parachute having a first set of physical attributes optimized for a first set of conditions and a second aircraft recovery parachute having a second set of physical attributes optimized for a second set of conditions different from the first.

Abstract: An inner middle rotor is rotated while an inner front rotor, an inner back rotor, and an outer rotor are not rotated. The inner middle rotor is surrounded by the inner front rotor, the inner back rotor, the outer rotor, and a fuselage. After rotating the inner middle rotor while not rotating the inner front rotor, the inner back rotor, and the outer rotor, the inner middle rotor, the inner front rotor, the inner back rotor, and the outer rotor are simultaneously rotated.

Abstract: Boundary information for a three-dimensional (3D) flying space is obtained. An input associated with steering a vehicle is received from an input device and location information associated with the vehicle is received from a location sensor. A control signal for the vehicle is generated based at least in part on the boundary information, the input, and the location information. In the event the input would cause the vehicle to cross the boundary of the 3D flying space if obeyed, the control signal for the vehicle is generated so that the vehicle is prevented from crossing the boundary of the 3D flying space. In response to receiving an indication associated with the vehicle landing, the boundary information is modified so that the 3D flying space includes a landing pathway.

Abstract: An inner middle rotor is rotated while an inner front rotor, an inner back rotor, and an outer rotor are not rotated. The inner middle rotor is surrounded by the inner front rotor, the inner back rotor, the outer rotor, and a fuselage. After rotating the inner middle rotor while not rotating the inner front rotor, the inner back rotor, and the outer rotor, the inner middle rotor, the inner front rotor, the inner back rotor, and the outer rotor are simultaneously rotated.

Abstract: Boundary information associated with a three-dimensional (3D) flying space is obtained, including a boundary of the 3D flying space. Location information associated with an aircraft is obtained, including a location of the aircraft. Information is presented based at least in part on the boundary information associated with the 3D flying space and the location information associated with the aircraft, including by presenting, in a display, the boundary of the 3D flying space and an avatar representing the aircraft at the location of the aircraft.

Abstract: Boundary information for a three-dimensional (3D) flying space is obtained. An input associated with steering a vehicle is received from an input device and location information associated with the vehicle is received from a location sensor. A control signal for the vehicle is generated based at least in part on the boundary information, the input, and the location information. In the event the input would cause the vehicle to cross the boundary of the 3D flying space if obeyed, the control signal for the vehicle is generated so that the vehicle is prevented from crossing the boundary of the 3D flying space. In response to receiving an indication associated with the vehicle landing, the boundary information is modified so that the 3D flying space includes a landing pathway.

Abstract: A takeoff location and a landing location are received for an autonomous vertical takeoff and landing (VTOL) vehicle that includes a plurality of rotors. An autonomous and noise-reduced flight trajectory for the autonomous VTOL vehicle is determined based at least in part on the takeoff location, the landing location, a jerk function, and a noise function, including by minimizing the jerk function and minimizing the noise function. A set of one or more desired forces or moments is determined for the autonomous VTOL vehicle based at least in part on autonomous and noise-reduced flight trajectory. A plurality of motor control signals is determined for the plurality of rotors based at least in part on the set of one or more desired forces or moments.

Abstract: Boundary information associated with a three-dimensional (3D) flying space is obtained, including a boundary of the 3D flying space. Location information associated with an aircraft is obtained, including a location of the aircraft. Information is presented based at least in part on the boundary information associated with the 3D flying space and the location information associated with the aircraft, including by presenting, in a display, the boundary of the 3D flying space and an avatar representing the aircraft at the location of the aircraft.

Abstract: In an embodiment, a system includes a frame configured to support a load, a first set of wheels provided on the frame, a second set of wheels provided on the frame, and a controller. The first set of wheels is configured to descend or ascend in response to the controller, and is oriented to move in a first direction. The second set of wheels is configured to descent or ascend in response to the controller, and is oriented to move in a different direction from the first direction. The controller configured to control the descent and ascent of the second set of wheels and the first set of wheels.

Abstract: A system is disclosed that includes an interface which receives sensor information associated with a vehicle, a severing tool, a parachute load limiting device state controller, and a reefing device. The controller determines, based at least in part on the sensor information, whether to instruct the severing tool to release a reefing device prior to parachute deployment. If it is determined to instruct the severing tool to release the reefing device prior to the parachute deployment, the severing tool is so instructed. If it is determined to not instruct the severing tool to release the reefing device prior to the parachute deployment, the reefing device is configured to be situated around a parachute canopy to constrain the parachute canopy during an initial state and slide down the parachute canopy to a position below the parachute canopy to constrain one or more parachute tethers.

Abstract: Various embodiments include a thermal storage system for storing energy in a graphite thermal storage structure and a thermal shutter assembly configured to control the transmission of heat from the graphite thermal storage structure to a thermal energy receiver, such as a heat exchanger or material processing crucible. A thermal storage block, which may be made of graphite, may be isolated by insulation except for the thermal shutter assembly. Energy may be stored in the graphite thermal storage block by applying energy to the block to raise its temperature to maximum operation temperature. Stored energy may then be harvested in a controlled manner by a control system actuating the thermal shutter to expose the thermal energy receiver to thermal radiation.

Abstract: An inner middle rotor is rotated while an inner front rotor, an inner back rotor, and an outer rotor are not rotated. The inner middle rotor is surrounded by the inner front rotor, the inner back rotor, the outer rotor, and a fuselage. After rotating the inner middle rotor while not rotating the inner front rotor, the inner back rotor, and the outer rotor, the inner middle rotor, the inner front rotor, the inner back rotor, and the outer rotor are simultaneously rotated.

Abstract: A multi-modal aircraft recovery system is disclosed. In various embodiments, the system includes a first aircraft recovery parachute having a first set of physical attributes optimized for a first set of conditions and a second aircraft recovery parachute having a second set of physical attributes optimized for a second set of conditions different from the first.

Abstract: An inner middle rotor is rotated while an inner front rotor, an inner back rotor, and an outer rotor are not rotated. The inner middle rotor is surrounded by the inner front rotor, the inner back rotor, the outer rotor, and a fuselage. After rotating the inner middle rotor while not rotating the inner front rotor, the inner back rotor, and the outer rotor, the inner middle rotor, the inner front rotor, the inner back rotor, and the outer rotor are simultaneously rotated.

Abstract: A multi-modal aircraft recovery system is disclosed. In various embodiments, the system includes a first aircraft recovery parachute having a first set of physical attributes optimized for a first set of conditions and a second aircraft recovery parachute having a second set of physical attributes optimized for a second set of conditions different from the first.

Abstract: A system is disclosed that includes an interface which receives sensor information associated with a vehicle, a severing tool, a parachute load limiting device state controller, and a reefing device. The controller determines, based at least in part on the sensor information, whether to instruct the severing tool to release a reefing device prior to parachute deployment. If it is determined to instruct the severing tool to release the reefing device prior to the parachute deployment, the severing tool is so instructed. If it is determined to not instruct the severing tool to release the reefing device prior to the parachute deployment, the reefing device is configured to be situated around a parachute canopy to constrain the parachute canopy during an initial state and slide down the parachute canopy to a position below the parachute canopy to constrain one or more parachute tethers.