Clean fuel electric multirotor aircraft for personal air transportation and manned or unmanned operation

• US 10,370,088 B2
• Filed: 08/25/2017
• Issued: 08/06/2019
• Est. Priority Date: 05/01/2014
• Status: Active Grant

• Current Assignee: Alakai Technologies Corporation (Guardian Mobility Corp.)
• Original Assignee: Alakai Technologies Corporation (Guardian Mobility Corp.)
• Inventors: Morrison, Brian D.
• Primary Examiner(s): Bonzell, Philip J
• Application Number:
  US15/686,625
• Publication Number:
  US 20180001994A1
• Time in Patent Office: 711 Days
• CPC Class Codes: B64C 13/18 using automatic pilot
• CPC Class Codes: B64C 27/08 with two or more rotors
• CPC Class Codes: B64D 2041/005 Fuel cells
• CPC Class Codes: B64D 27/026 comprising different types of power plants, e.g. combination of a piston engine and a gas-turbine Hybrid electric aircraft B64D27/33
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: B64U 10/17 Helicopters flying platforms B64U10/13
• CPC Class Codes: B64U 2101/60 for transporting passengers; for transporting goods other than weapons
• CPC Class Codes: B64U 2201/20 Remote controls
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 50/32 generated by fuel cells
• CPC Class Codes: B64U 70/90 Launching from or landing on platforms
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration
• CPC Class Codes: G05D 1/0077 using redundant signals or controls
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y02T 90/40 Application of hydrogen technology to transportation, e.g. using fuel cells

Abstract

Methods and systems for a full-scale vertical takeoff and landing manned or unmanned aircraft, having an all-electric, low-emission or zero-emission lift and propulsion system, an integrated ‘highway in the sky’ avionics system for navigation and guidance, a tablet-based motion command, or mission planning system to provide the operator with drive-by-wire style direction control, and automatic on-board-capability to provide traffic awareness, weather display and collision avoidance. Automatic computer monitoring by a programmed triple-redundant digital autopilot computer controls each motor-controller and motor to produce pitch, bank, yaw and elevation, while simultaneously restricting the flight regime that the pilot can command, to protect the pilot from inadvertent potentially harmful acts that might lead to loss of control or loss of vehicle stability. By using the results of the state measurements to inform motor control commands, the methods and systems contribute to the operational simplicity, reliability and safety of the vehicle.

Claims

1. A full-scale, multirotor all-electric aircraft system sized, dimensioned, and configured for transporting one or more human occupants and/or payload, the system comprising:

a multirotor airframe fuselage, having a structure supporting the total vehicle weight together with the one or more human occupants and/or payload;

a plurality of motor and propeller assemblies attached to the multirotor airframe fuselage, the plurality of motor and propeller assemblies each comprising a plurality of pairs of propeller blades, the plurality of motor and propeller assemblies being controlled by a plurality of motor controllers;

an electrical power-system configured to supply electrical voltage and current;

a power distribution monitoring and control subsystem for monitoring and controlling distribution of the supplied electrical voltage and current to the plurality of motor controllers and an avionics system;

wherein the plurality of motor controllers are commanded by one or more autopilot control units, where the one or more autopilot control units control the commanded electrical voltage and torque or current for each of the plurality of motor and propeller assemblies;

where the one or more autopilot control units comprise input/output interfaces comprising at least one of an interface selected from serial RS232, Controller Area Network (CAN), Ethernet, analog voltage inputs, analog voltage outputs, pulse-width-modulated outputs for motor control, an embedded or stand-alone air data computer, an embedded or stand-alone inertial measurement device, and one or more cross-communication channels or networks;

wherein the one or more autopilot control units determine an action to command to avoid collisions with the nearby aircraft, wherein the multirotor all-electric aircraft system is controlled within safety, reliability, performance, and redundancy measures necessary to protect human life and maintain flight-worthiness using a redundant autopilot system to manage motors and/or motor controllers, monitor operation and/or position of the aircraft, and maintain vehicle stability; and

perform calculations for flight path optimization and collision avoidance, based upon a state of the multirotor all-electric aircraft, states of the nearby aircraft, and available flight path dynamics.

2. The system of claim 1, further comprising controlling the plurality of motor and propeller assemblies to operate the multirotor all-electric aircraft system within predetermined aircraft performance limitations, using a triple redundant autopilot system to manage motors and/or motor controllers, to monitor one or more of operation and position and velocity and acceleration of the vehicle, and to maintain vehicle stability, controllers for navigation and landing lights, primary and backup hardware and software systems, and automatic dependent surveillance-B to provide traffic and situational awareness, weather display and collision avoidance warnings.

3. The system of claim 1, further comprising landing skids or wheels connected to the multirotor airframe fuselage supporting the multirotor all-electric aircraft system.

4. The system of claim 1, wherein the plurality of motor controllers are high-voltage, high-current air-cooled or liquid-cooled controllers.

5. The system of claim 1, wherein the multirotor all-electric aircraft system is operable autonomously, by remote operation by a human pilot, or by a human pilot and wherein some or all of the position and control instructions are performed outside the multirotor all-electric aircraft system, by using a broadband or 802.11 Wi-Fi network or Radio Frequency (RF) bidirectional data-link between the multirotor all-electric aircraft system and ground-based equipment.

6. The system of claim 1, wherein the multirotor all-electric aircraft system is configured for autonomous operation, remote operation by a human pilot, or operation by a human pilot, and wherein some or all of the position and control instructions are performed inside the multirotor all-electric aircraft system by using mission planning software to designate a route, destination, and altitude profile for the multirotor all-electric aircraft system to fly, forming a flight plan for that flight to be performed with or without human involvement.

7. The system of claim 1, wherein a source of power for the plurality of motor and propeller assemblies further comprises one or more hydrogen-powered fuel-cells, high-voltage battery arrays, or hydrocarbon-fueled motors, where each motor is fueled by compressed natural gas (CNG), liquefied petroleum gas (LPG), aviation standard fuel (avgas), diesel, gasoline, or other suitable fuel and each fuel cell is powered by hydrogen or other suitable fuel.

8. The system of claim 7, wherein the one or more hydrogen-powered fuel-cells, high-voltage battery arrays, or hydrocarbon-fueled motors include diode or field-effect transistor (FET) isolation between each electrical source and an electrical main bus and the one or more hydrogen-powered fuel-cells, high-voltage battery arrays, or hydrocarbon-fueled motors.

9. The system of claim 1, further comprising:

an On/Off key connected to a high-current contactor that isolates the electrical power-system from the plurality of motor and propeller assemblies when power from the electrical power-system is not required;

a mission display system that displays to an operator information about a state of performance metrics of the electrical power-system;

a motor-enable safety switch providing a means of disabling and enabling the plurality of motor and propeller assemblies;

an external refueling connector compatible with infrastructure for electric powered vehicles, to enable aircraft system refueling;

a dual display system comprising software operating on a touch-tablet computer or avionics display system;

a dual mission controller tablet computer comprising the software operating on the touch-tablet computer or the avionics display system, with wired or wireless (RF) connections to the one or more autopilot control units;

a wirelessly connected or wire-connected Automatic Dependent Surveillance-Broadcast (ADSB) unit providing the software with collision avoidance, traffic, and weather information to and from the multirotor all-electric aircraft system;

one or more autopilot control units comprising a single-board computer and input/output interfaces comprising at least one of interface selected from serial RS232, Controller Area Network (CAN), Ethernet, analog voltage inputs, analog voltage outputs, pulse-width-modulated outputs for motor control, an embedded or stand-alone air data computer, an embedded or stand-alone inertial measurement device, and one or more cross-communication channels or networks;

a DC-DC converter or starter/alternator configured to down-shift at least a portion of a primary voltage of the multirotor all-electric aircraft system to either 24V or 28V standards for avionics and non-motor purposes, with a 24V or 28V battery to provide local current storage;

a tablet computer operating mission software, or a throttle or foot control pedal, providing a variable voltage or potentiometer setting indicative of commanded thrust;

a tablet computer operating mission software, or a 2-axis joystick or control yoke, providing two independent sets of variable voltage or potentiometer settings indicative of pitch command and bank command;

a means of combining pitch, roll, yaw, throttle, and other desired information onto a serial line, using servo controls, in such a way that multiple channels of command data pass from tablet to the one or more autopilot control units over the serial line, where control information is packaged in a plurality of frames that repeat at a periodic rate;

the one or more autopilot control units operating control algorithms generating commands to each of the plurality of motor controllers, managing and maintaining vehicle stability, and monitoring feedback.

10. The system of claim 9, wherein the avionics display system for the multirotor all-electric aircraft system comprises an interface to the ADSB unit, operable to:

receive broadcast data from nearby aircraft;

transmit desired state information to the one or more autopilot control units to avoid collisions with the nearby aircraft;

the one or more autopilot control units determine an action to command to avoid the collisions with the nearby aircraft;

broadcast position data of the multirotor all-electric aircraft system to the nearby aircraft to provide the nearby aircraft with the position information to avoid potential collisions;

receive weather data and display the weather data on the avionics display system;

enable operation of the multirotor all-electric aircraft system with no requirement to interact with or communicate with air traffic controllers; and

perform calculations for flight path optimization and collision avoidance, based upon a state of the multirotor all-electric aircraft, states of the nearby aircraft, and available flight path dynamics under the National Airspace System or equivalent systems in other countries.

11. The system of claim 1, wherein the plurality of motor and propeller assemblies comprise pancake, axial flux brushless synchronous three-phase AC or DC electric motors.

12. The system of claim 11, wherein the plurality of motor and propeller assemblies are an aircraft motor.

13. The system of claim 11, wherein the plurality of motor controllers and propeller assemblies provide lift or thrust forces predominantly in a vertical direction during takeoff and landing.

14. The system of claim 11, wherein pairs of propellers operate in counter-rotating fashion, so as to produce no net torque to the multirotor all-electric aircraft system, in such a way that a tail rotor is not necessary for stabilized and controlled rotary aircraft operation.

15. The system of claim 14, wherein pairs of the plurality of motor and propeller assemblies operate at different RPM or Torque settings to produce slightly differing amounts of thrust under computer control, thereby imparting a pitch moment, or a bank moment, or a yaw moment, or a change in altitude, or simultaneously combinations thereof, to the multirotor all-electric aircraft system, using position feedback from on-board inertial, atmospheric, global positioning system (GPS), and magnetic sensors to maintain flight stability.

16. The system of claim 1, wherein the electrical power-system comprises one of:

a hydrogen fuel-cell system comprising a hydrogen storage tank, one or more fuel cell subsystems, one or more air-driven turbochargers supplying air to the one or more of fuel cell subsystems, and of the one or more fuel cells supplying voltage and current to the plurality of motor controllers, wherein the hydrogen fuel-cell system combines hydrogen from the hydrogen storage tank with air to supply the electrical voltage and current;

or

a battery subsystem comprising a high-voltage battery array, battery monitoring and charging subsystem;

or

a motor-generator system comprising a fuel storage tank, one or more hydrocarbon-fueled motors, and one or more motor-driven high voltage generators to supply the current to the plurality of motor controllers.

17. The system of claim 16, wherein the electrical power-system further comprises multiple high-current battery cells mounted within modular enclosures of the multirotor airframe fuselage that require periodic charging while not in flight, comprising:

a battery management system configured to monitor battery voltage, current, charge, and status of the multiple high-current battery cells; and

a recharging system compatible with automotive electric vehicle recharging stations, according to J1772 standards;

wherein the multiple high-current battery cells are configured to recharge the multirotor aircraft'"'"'s batteries at an origin, at a destination, or at roadside EV charging stations;

wherein the multiple high-current battery cells are configured to operate the multirotor all-electric aircraft system in a manned or unmanned local surveillance mode when tethered by a power cable; and

wherein the electrical power-system uses a portion of the main supplied power of the multirotor all-electric aircraft system to power onboard avionics through a DC-to-DC converter or starter-alternator, thereby alleviating a need for separate charger and charge-ports for batteries powering the onboard avionics.

18. A full-scale, multirotor aircraft sized, dimensioned, and configured for transporting one or more human occupants and/or payload, the multirotor aircraft comprising:

a plurality of motor and propeller assemblies attached to a multirotor airframe fuselage;

a plurality of motor controllers controlling each of the plurality of motor and propeller assemblies;

an electrical power-system configured to supply electrical voltage and current to the plurality of motor and propeller assemblies;

a power distribution monitoring and control subsystem that monitors and controls distribution of the supplied electrical voltage and current from the electrical power-system to the plurality of motor controllers; and

one or more autopilot control units that command the plurality of motor controllers to control the supplied electrical voltage and torque or current to the plurality of motor and propeller assemblies from the power distribution monitoring and control subsystem and perform calculations for flight path optimization and collision avoidance, based upon a state of the full-scale, multirotor aircraft, states of the nearby aircraft, and available flight path dynamics.

19. The aircraft of claim 18, wherein the electrical power-system is powered by at least one of hydrogen-powered fuel-cells, high-voltage battery arrays, or hydrocarbon-fueled combustion motors.

20. The aircraft of claim 18, wherein the plurality of motor and propeller assemblies are commanded to operate at different RPM settings to produce slightly differing amounts of thrust under control of the one or more autopilot control units to produces lift, thrust, pitch, bank, yaw, vertical, lateral, and longitudinal motion of the aircraft.

21. The aircraft of claim 18, wherein the one or more autopilot control units measure vehicle state information of at least one of pitch, bank angle, yaw, and accelerations for maintaining stability of the aircraft.

22. The aircraft of claim 18, wherein the one or more autopilot control units comprise at least two redundant autopilot control units.

23. The aircraft of claim 22, wherein the one or more autopilot control units that command the plurality of motor controllers execute a voting process that establishes a quorum between the at least two redundant autopilot control units for motor commands to be transmitted to the plurality of motor and propeller assemblies.

24. The aircraft of claim 23, wherein the at least two redundant autopilot control units communicate the voting process over a redundant network.