Abstract: A system is disclosed to detect failure of a diode that is connected in series with a battery and a contactor or other switch configured to connect the battery to a load when the contactor or other switch is in a closed position and to isolate the battery from the load when the contactor or other switch is in an open position. In various embodiments, the system includes a high value resistor connected between the anode terminal of the diode and ground, the connection to the anode terminal being on a load side of the contactor or other switch; and a voltage meter configured to measure a voltage across the high value resistor at least during a test in which a voltage is applied to a bus associated with the load while the contactor or other switch is in the open position.

Abstract: Electrically powered vehicles with redundant power distribution circuits employ inverters and a multi-phase alternating current (AC) motor. An electrically powered vehicle includes batteries, inverters, interphase transformers, and a three-phase AC motor. Each of the inverters generates a three-phase AC input from power supplied by an associated one of the batteries. The interphase transformers generate drive phases for the AC motor from the three-phase AC inputs generated by the inverters.

Abstract: A power distribution circuit for an electrically powered aircraft includes a plurality of batteries and a plurality of electric propulsion systems. A plurality of power distribution circuits each couple a battery of the plurality of batteries to two or more electric propulsion systems. The plurality of electric propulsion systems are positioned on the aircraft to apply balanced forces to the aircraft such that in the event of a failure, the aircraft remains stable and only experiences a loss in altitude or speed.

Abstract: Embodiments provide a propeller ground stop mechanism configured to keep an unpowered propeller of an aircraft (e.g. when the aircraft is on the ground and not operating) static. The propeller is prevented from rotating due to external forces (e.g. an air flow caused by wind, manual rotation of the propeller). When the propeller is powered, and the propeller is providing thrust, the propeller ground stop mechanism automatically disengages and does not provide any drag. Among various benefits, the propeller ground stop mechanism provides added safety to the ground support personnel.

Abstract: An electrically powered vehicle includes a plurality of batteries and a plurality of DC to DC converters, each coupled to a respective battery of the plurality of batteries. Each DC to DC converter transfers power from a respective battery to a common DC bus. The common DC bus is coupled to a plurality of inverter circuits that convert the DC power to AC power. A plurality of electric motors receive power from the plurality of inverter circuits to propel the vehicle. During a regenerative event, the DC to DC converters can transfer power from the motors back to the batteries. In response to the failure of a battery, the DC to DC converters can isolate the remainder of the system from the failure.

Abstract: A power delivery system includes a controller, configured to receive a voltage indication signal indicating a measured voltage of a battery management system and to determine whether first and second diodes of the battery management system are faulty based on the voltage indication signal. The controller is also configured to respectively receive first and second current indication signals from first and second current sensors of the battery management system and to determine whether the first and second diodes of the first battery management system are faulty based on the first and second current indication signals.

Abstract: Embodiments provide a compact vertiport system. The vertiport system may be efficient and compact by combining, into one space and time period, multiple activities that typically take place in different spaces and different times. For example, when an aircraft is being moved from a landing zone to a takeoff zone, the aircraft may also be charged simultaneously. Also, passenger exchange may take place while the aircraft is being moved. As a result, compact vertiport systems may fit into smaller spaces (e.g., tops of buildings, or smaller plots of land).

Abstract: A power distribution circuit for an electrically powered aircraft includes a plurality of batteries and a plurality of electric propulsion systems. A plurality of isolated power distribution circuits each couple a battery of the plurality of batteries to two or more electric propulsion systems. The plurality of electric propulsion systems are positioned on the aircraft to apply balanced forces to the aircraft such that in the event of a failure, the aircraft remains stable and only experiences a loss in altitude or speed.

Abstract: Disclosed is an electric aircraft, which includes a fuselage and at least one wing coupled to the fuselage. The electric aircraft includes a plurality of tilting fans coupled to the at least one wing, the plurality of tilting fans being configured to move between a vertical lift position and a forward flight position. The electric aircraft includes a plurality of tilting mechanisms coupled with at least one tilting fan. The electric aircraft includes a first actuator coupled to a first subset of the plurality of tilting mechanisms. The first subset of tilting mechanisms are identified among the plurality of tilting mechanisms according to a coupling scheme. The first actuator tilts a first group of tilting fans coupled to the first subset of the plurality of tilting mechanisms simultaneously.

Abstract: Techniques described here provide a rotor and a method of making a rotor. In an embodiment, a method of making a rotor includes forming a magnet array by assembling a plurality of magnets into the magnet array, providing pre-preg adjacent to the magnet array, co-curing the magnet array with the pre-preg, and magnetizing the magnet array subsequent to the formation of the magnet array.

Abstract: At least an output shaft angle associated with an output shaft is initialized to a known value where the output shaft is coupled to a motor shaft via a set of one or more gears. A direction of rotation associated with the motor shaft is determined using a plurality of discrete Hall sensors in the motor and the output shaft angle is updated using an incremental value and the direction of rotation.

Abstract: A coupled battery and motor controller thermal management system is disclosed. In various embodiments, a motor controller and a heat sink are coupled thermally to a battery. At least a portion of waste heat generated by the motor controller is transferred to the thermal mass of the battery during at least a first mode of operation in which a relatively low amount of ambient air flows through the heat sink.

Abstract: A power delivery system includes a controller, configured to receive a voltage indication signal indicating a measured voltage of a battery management system and to determine whether first and second diodes of the battery management system are faulty based on the voltage indication signal. The controller is also configured to respectively receive first and second current indication signals from first and second current sensors of the battery management system and to determine whether the first and second diodes of the first battery management system are faulty based on the first and second current indication signals.

Abstract: Techniques described here provide a rotor and a method of making a rotor. In an embodiment, a method of making a rotor includes forming a magnet array by assembling a plurality of magnets into the magnet array, providing pre-preg adjacent to the magnet array, co-curing the magnet array with the pre-preg, and magnetizing the magnet array subsequent to the formation of the magnet array.

Abstract: Embodiments of cooling a motor controlling using a motor are disclosed. In some embodiments, a system includes an electric motor including at least one rotor with integrated features positioned and configured to pull air into and through the electric motor. The system also includes at least one motor controller each comprising a heat sink positioned in an air intake path from a source of air to the electric motor. A method of manufacturing the system includes arranging at least one motor controller and at least one electric motor, coupling the at least one motor controller and at least one electric motor via a flexible duct, and adapting the arrangement of the at least one motor controller and the at least one electric motor to passively provide cooling via airflow through the at least one motor controller and at least one electric motor in proportion to a load on the at least one electric motor.

Abstract: Embodiments provide an electric aircraft with a plurality of lift fan assemblies that are configured to provide vertical lift, and one or more pusher propellers that are configured to provide forward thrust. The lift fan assemblies may be coupled to the wings of the aircraft via one or more support structures, and the wings may be coupled to an upper region of the fuselage. The pusher propeller(s) may be coupled to a tailing end of the fuselage. The lift fan assemblies and the pusher propeller(s) may provide thrust and movement in directions that are orthogonal to one another. A control system coupled to the aircraft may control the lift fan assemblies and the one or more pusher propellers to activate, increase in power, and decrease in power. The lift fan assemblies and the one or more pusher propellers may be operated separately, and may be active at different times.

Abstract: An electrically powered vehicle comprises a DC bus and a plurality of batteries, each coupled in parallel to the DC bus. At least one switch is coupled in series between at least one battery of the plurality of batteries and the DC bus and a plurality of inverter circuits are each coupled in parallel to the DC bus. A plurality of motors are each coupled to a respective inverter circuit of the plurality of inverter circuits. In various embodiments the electrically powered vehicle further comprises a plurality of switches, each switch coupled in series between a respective battery of the plurality of batteries.

Abstract: An electrically powered vehicle includes a plurality of batteries and a plurality of DC to DC converters, each coupled to a respective battery of the plurality of batteries. Each DC to DC converter transfers power from a respective battery to a common DC bus. The common DC bus is coupled to a plurality of inverter circuits that convert the DC power to AC power. A plurality of electric motors receive power from the plurality of inverter circuits to propel the vehicle. During a regenerative event, the DC to DC converters can transfer power from the motors back to the batteries. In response to the failure of a battery, the DC to DC converters can isolate the remainder of the system from the failure.

Abstract: Method and assembly for producing a magnet. A method of manufacturing a magnet includes transferring magnetic powder into a die cavity. The die cavity has a first side and a second side opposite to the first side. First magnetic flux lines are induced to extend into the magnetic powder through the first side and orthogonal to the first side. The first magnetic flux lines extend out of the magnetic powder through a top surface of the magnetic powder. Second magnetic flux lines are induced to extend into the magnetic powder through the second side and orthogonal to the second side. The second magnetic flux lines extend out of the magnetic powder through the top surface of the magnetic powder. Pressure is applied to the magnetic powder disposed within the die cavity.

Abstract: A system is disclosed to detect failure of a diode that is connected in series with a battery and a contactor or other switch configured to connect the battery to a load when the contactor or other switch is in a closed position and to isolate the battery from the load when the contactor or other switch is in an open position. In various embodiments, the system includes a high value resistor connected between the anode terminal of the diode and ground, the connection to the anode terminal being on a load side of the contactor or other switch; and a voltage meter configured to measure a voltage across the high value resistor at least during a test in which a voltage is applied to a bus associated with the load while the contactor or other switch is in the open position.