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 commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: 1. A vertical takeoff and landing vehicle which includes an allocation block that receives a set of desired forces or desired moments and a health metric associated with at least one of: (1) a motor controller or (2) a rotor that operates in a vertical takeoff and landing mode at least some of the time. A command signal is determined per a first manner that attempts to satisfy both the set of desired forces or desired moments and the health metric. If the command signal is unable to be determined in the first manner, a second manner is used that prioritizes flight control associated with one or more of a roll axis or a pitch axis over flight control associated with a yaw axis where the axes are mutually orthogonal. The command signal is output to the motor controller that controls the rotor using the command signal.

Abstract: Commands, including a first and second command associated with a first and second rotor module, are determined based at least in part on a set of desired forces or moments and a plurality of health metrics, including by determining a plurality of differences between the plurality of health metrics and a threshold and assigning a lower thrust value to the first command based at least in part on the first difference and a higher thrust value to the second command based at least in part on the second difference, where the first difference indicates a higher degree of wear on the first rotor module than the second difference indicates for the second rotor module. The commands are sent to the rotor modules and after the commands are performed, updated health metrics are determined.

Abstract: A commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: A configuration instruction associated with configuring a plurality of batteries which supply power to a plurality of motors in a vehicle is received. The batteries are configuring as specified by the configuration instruction, where the batteries are able to be configured in a plurality of configurations, including: a first configuration where at least some of the batteries are electrically connected together in parallel and a second configuration where at least some of the batteries are electrically connected together in series.

Abstract: A first propeller has a shorter blade length and a lower inertia than a second propeller. An electromagnetic field emitter is coupled to one of the first propeller or the second propeller and an electromagnetic field receptor is coupled to the other one that is not coupled to the electromagnetic field emitter. The electromagnetic field emitter emits an electromagnetic field. In response to the electromagnetic field: the electromagnetic field receptor and its coupled propeller rotate in a first rotational direction; and the electromagnetic field emitter and its coupled propeller rotate in a second and counter-rotational direction. In response to a second electromagnetic field associated with increasing torque: the first propeller increases and subsequently decreases its rotational speed; and the second propeller increases its rotational speed at a slower rate than the increase in the rotational speed of the first propeller.

Abstract: A configuration instruction associated with configuring a plurality of batteries which supply power to a plurality of motors in a vehicle is received. The batteries are configuring as specified by the configuration instruction, where the batteries are able to be configured in a plurality of configurations, including: a first configuration where at least some of the batteries are electrically connected together in parallel and a second configuration where at least some of the batteries are electrically connected together in series.

Abstract: A commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: A commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: Commands, including a first and second command associated with a first and second rotor module, are determined based at least in part on a set of desired forces or moments and a plurality of health metrics, including by determining a plurality of differences between the plurality of health metrics and a threshold and assigning a lower thrust value to the first command based at least in part on the first difference and a higher thrust value to the second command based at least in part on the second difference, where the first difference indicates a higher degree of wear on the first rotor module than the second difference indicates for the second rotor module. The commands are sent to the rotor modules and after the commands are performed, updated health metrics are determined.

Abstract: A set of one or more desired forces or desired moments associated with an aircraft having a plurality of rotor modules is received. A plurality of health metrics associated with the plurality of rotor modules is received. A plurality of commands for the plurality of rotor modules is determined based at least in part on the set of desired forces or desired moments and the plurality of health metrics. The plurality of commands is sent to the plurality of rotor modules where each rotor module in the plurality of rotor modules is configured to perform a corresponding command in the plurality of commands.

Abstract: A first propeller has a shorter blade length and a lower inertia than a second propeller. An electromagnetic field emitter is coupled to one of the first propeller or the second propeller and an electromagnetic field receptor is coupled to the other one that is not coupled to the electromagnetic field emitter. The electromagnetic field emitter emits an electromagnetic field. In response to the electromagnetic field: the electromagnetic field receptor and its coupled propeller rotate in a first rotational direction; and the electromagnetic field emitter and its coupled propeller rotate in a second and counter-rotational direction. In response to a second electromagnetic field associated with increasing torque: the first propeller increases and subsequently decreases its rotational speed; and the second propeller increases its rotational speed at a slower rate than the increase in the rotational speed of the first propeller.

Abstract: A system which includes a first propeller, a second propeller, an electromagnetic field emitter that is coupled to the first propeller, and an electromagnetic field receptor that is coupled to the second propeller. The electromagnetic field emitter emits an electromagnetic field and in response to the electromagnetic field, the electromagnetic field receptor and the second propeller rotate in a first rotational direction and the electromagnetic field emitter and the first propeller rotate in a second and counter-rotational direction.

Abstract: A system which includes a first propeller, a second propeller, an electromagnetic field emitter that is coupled to the first propeller, and an electromagnetic field receptor that is coupled to the second propeller. The electromagnetic field emitter emits an electromagnetic field and in response to the electromagnetic field, the electromagnetic field receptor and the second propeller rotate in a first rotational direction and the electromagnetic field emitter and the first propeller rotate in a second and counter-rotational direction.

Abstract: A configuration instruction associated with configuring a plurality of batteries which supply power to a plurality of motors in a vehicle is received. The batteries are configuring as specified by the configuration instruction, where the batteries are able to be configured in a plurality of configurations, including: a first configuration where at least some of the batteries are electrically connected together in parallel and a second configuration where at least some of the batteries are electrically connected together in series.

Abstract: A commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: A commanded control signal is compared against an adaptive control signal in order to detect a rotor strike by a rotor included in an aircraft, wherein the adaptive control signal is associated with controlling the rotor and the adaptive control signal varies based at least in part on the commanded control signal and state information associated with the rotor. In response to detecting the rotor strike, a control signal to the rotor is adjusted in order to reduce a striking force associated with the rotor.

Abstract: A configuration instruction associated with configuring a plurality of batteries which supply power to a plurality of motors in a vehicle is received. The batteries are configuring as specified by the configuration instruction, where the batteries are able to be configured in a plurality of configurations, including: a first configuration where at least some of the batteries are electrically connected together in parallel and a second configuration where at least some of the batteries are electrically connected together in series.

Abstract: A distance determination system is disclosed. In various embodiments, the system includes a transmitter configured to transmit a first pulse at a first frequency and a second pulse at a second frequency; a receiver configured to receive audio signals; and a processor coupled to the receiver and configured to detect whether an intermodulation product of the first pulse and the second pulse is present and above a threshold amplitude in an audio signal received by the receiver; and determine, based at least in part on whether the intermodulation product of the first pulse and the second pulse is detected to be present and above a threshold amplitude, whether a distance to a surface is greater than a distance corresponding to the first pulse and the second pulse.