Personal aircraft
A safe, quiet, easy to control, efficient, and compact aircraft configuration is enabled through the combination of multiple vertical lift rotor assemblies, tandem wings, and forward thrust propellers. The vertical lift rotor assemblies, in combination with a front and rear wing, permits a balancing of the center of lift with the center of gravity for both vertical and horizontal flight. This wing and multiple rotor system has the ability to tolerate a relatively large variation of the payload weight for hover, transition, or cruise flight while also providing vertical thrust redundancy. The propulsion system uses multiple lift rotor assemblies and forward thrust propellers of a small enough size to be shielded from potential blade strike and provide increased perceived and real safety to the passengers. Using multiple independent rotor assemblies provides redundancy and the elimination of single point failure modes that can make the vehicle non-operable in flight.
1 . An aircraft comprising:
a fuselage;
a first plurality of lift rotor assemblies coupled to a first side of the fuselage, at least two of the first plurality of lift rotor assemblies having different cant angles from each other;
a second plurality of lift rotor assemblies coupled to a second side of the fuselage, at least two of the second plurality of lift rotor assemblies having different cant angles from each other;
one or more propellers coupled to the fuselage for providing forward thrust; and
a flight computer, coupled to the fuselage, and configured to transition the aircraft between a forward flight and a vertical flight by activating and deactivating one or more of the first plurality of lift rotor assemblies, the second plurality of lift rotor assemblies or the one or more propellers.
2 . The aircraft of claim 1 , wherein the different cant angles of the at least two of the first plurality of lift rotor assemblies are opposite symmetric angles with respect to a plane passing through the first plurality of lift rotor assemblies.
3 . The aircraft of claim 1 , wherein the different cant angles of the at least two of the second plurality of lift rotor assemblies are opposite symmetric angles with respect to a plane passing through the second plurality of lift rotor assemblies.
4 . The aircraft of claim 1 , wherein the first plurality of lift rotor assemblies includes at least 3 rotors and the second plurality of lift rotor assemblies includes at least 3 rotors.
5 . The aircraft of claim 1 , wherein the flight computer is further adapted to adjust an amount of thrust provided by each of the first plurality of lift rotors and each of the second plurality of lift rotors to compensate for a rotor failure.
6 . The aircraft of claim 1 , wherein the flight computer further comprises:
a sensor interface adapted to receive sensor data that indicates one or more of a position, an altitude, an attitude and a velocity of the aircraft; and
a rotor control module, coupled to the sensor interface, adapted to determine an amount of thrust required from each of the first plurality of lift rotor assemblies and each of the second plurality of lift rotor assemblies to achieve a desired orientation and to command independently each of the first plurality of lift rotor assemblies or the each of the second plurality of lift rotor assemblies to produce the determined required thrust.
7 . The aircraft of claim 6 , wherein the flight computer further comprises:
a propeller control module coupled to the sensor interface, adapted to determine an amount of forward thrust required from the one or more propellers and to command the one or more propellers to produce the required thrust.
8 . The aircraft of claim 1 , wherein the first plurality of lift rotor assemblies is located on a starboard side of the fuselage and the second plurality of lift rotor assemblies is located on a port side of the fuselage.
9 . The aircraft of claim 1 , further comprising an aft wing coupled to the fuselage, wherein the aft wing is located aft of the center of gravity.
10 . The aircraft of claim 1 , wherein each rotor in the first plurality of lift rotor assemblies and the second plurality of lift rotor assemblies includes a rotor and a motor, wherein the rotor includes a plurality of blades coupled to a hub, the motor comprises a stationary part and a rotating part, and the rotor is attached to the rotating part of the motor.
11 . The aircraft of claim 10 , further comprising a power system powering the motors of the first plurality of lift rotor assemblies and the second plurality of lift rotor assemblies.
12 . The aircraft of claim 11 , wherein the power system is electric or hybrid-electric.
13 . The aircraft of claim 1 , wherein a first half of all lift rotors of the aircraft rotate in a first direction, and a second half of all lift rotors rotate in a second direction opposite to the first direction.
14 . The aircraft of claim 1 , wherein the aircraft is an autonomous aircraft configured for flight without a pilot onboard.
15 . The aircraft of claim 1 , wherein the first plurality of lift rotor assemblies and the second plurality of lift rotor assemblies are coupled to the fuselage via a plurality of booms.
16 . The aircraft of claim 1 , wherein the first plurality of lift rotor assemblies are coupled to the first side of the fuselage via a first boom, and the second plurality of lift rotor assemblies are coupled to the second side of the fuselage via a second boom.
17 . The aircraft of claim 1 , wherein the first plurality of lift rotor assemblies and the second plurality of lift rotor assemblies are coupled to the fuselage via a plurality of booms.
18 . A method performed by a flight computer for controlling an aircraft to transition between vertical flight and forward flight, the method comprising:
activating a plurality of lift rotor assemblies coupled to the aircraft for vertical takeoff,
wherein the plurality of lift rotor assemblies include a first set of lift rotor assemblies located at a first side of the aircraft and a second set of lift rotor assemblies located at a second side of the aircraft,
wherein at least two of the first plurality of lift rotor assemblies have different cant angles from each other,
wherein at least two of the second plurality of lift rotor assemblies have different cant angles from each other;
activating one or more forward thrust propellers generating a forward speed; and
deactivating the plurality of lift rotor assemblies when the forward speed of the aircraft is greater than a stall speed of the aircraft.
19 . The method of claim 18 , wherein the different cant angles of the at least two of the first plurality of lift rotor assemblies are opposite symmetric angles with respect to a plane passing through the first plurality of lift rotor assemblies, and the different cant angles of the at least two of the second plurality of lift rotor assemblies are opposite symmetric angles with respect to a plane passing through the second plurality of lift rotor assemblies.
20 . An aircraft comprising:
the first set of lift rotor assemblies located at a first side of the aircraft;
the second set of lift rotor assemblies located at a second side of the aircraft; and
the flight computer configured to control the aircraft according to the method of claim 18 .