Multirotor aircraft with enhanced yaw control

• US 9,764,829 B1
• Filed: 06/09/2015
• Issued: 09/19/2017
• Est. Priority Date: 06/09/2015
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Beckman, Brian C., Elzinga, Michael John, Harris, Scott Raymond, LeGrand, III, Louis LeRoi, Schaffalitzky, Frederik
• Primary Examiner(s): Collins, Timothy D
• Assistant Examiner(s): ATWELL, JAMES BARRETT
• Application Number:
  US14/734,823
• Time in Patent Office: 833 Days
• CPC Class Codes: B64C 15/14 the jets being other than main propulsion jets jet flaps B64C9/38
• CPC Class Codes: B64C 27/08 with two or more rotors
• CPC Class Codes: B64C 27/12 Rotor drives
• CPC Class Codes: B64C 27/22 Compound rotorcraft, i.e. aircraft using in flight the features of both aeroplane and rotorcraft
• CPC Class Codes: B64C 27/52 Tilting of rotor bodily relative to fuselage of see-saw type construction B64C27/43
• CPC Class Codes: B64C 29/0033 the propellers being tiltable relative to the fuselage
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64U 10/13 Flying platforms
• CPC Class Codes: B64U 20/60 UAVs characterised by the material
• CPC Class Codes: B64U 2101/60 for transporting passengers; for transporting goods other than weapons
• CPC Class Codes: B64U 2101/64 for parcel delivery or retrieval
• CPC Class Codes: B64U 2201/10 autonomous, i.e. by navigating independently from ground or air stations, e.g. by using inertial navigation systems [INS]
• CPC Class Codes: B64U 30/10 Wings
• CPC Class Codes: B64U 30/12 Variable or detachable wings, e.g. wings with adjustable sweep
• CPC Class Codes: B64U 30/20 Rotors; Rotor supports
• CPC Class Codes: B64U 30/29 Constructional aspects of rotors or rotor supports; Arrangements thereof
• CPC Class Codes: B64U 40/20 for in-flight adjustment of the base configuration
• CPC Class Codes: B64U 50/13 using external fans or propellers
• CPC Class Codes: B64U 50/19 using electrically powered motors
• CPC Class Codes: B64U 50/30 Supply or distribution of electrical power

Abstract

A configuration of a multirotor aircraft that will facilitate enhanced yaw control includes one or more adjustable members that will twist the frame of the multirotor aircraft, thereby adjusting the orientation of the motors and propellers and enhancing the yaw control of the multirotor aircraft. In some implementations, the adjustable member(s) are passive and twist in response to differential thrusts generated by the propellers. In other implementations, the adjustable members are active and twist in response to a yaw command from the multirotor aircraft control system.

Claims

1. A multirotor aircraft, comprising:

a front frame;

a first motor arm coupled to the front frame and including a first motor and a second motor, the first motor at a first end of the first motor arm and the second motor at a second end of the first motor arm;

a rear frame;

a second motor arm coupled to the rear frame and including a third motor and a fourth motor, the third motor at a first end of the second motor arm and the fourth motor at a second end of the second motor arm; and

an adjustable member coupling the front frame to the rear frame; and

wherein;

the front frame rotates by a first rotation in a first direction about an axis via the adjustable member;

the rear frame rotates by a second rotation in a second direction about the axis via the adjustable member;

the axis is transverse to axes of rotation of the first, second, third, and fourth motors;

the first rotation is generated in response to a first differential thrust generated between the first motor and the second motor; and

the second rotation is generated in response to a second differential thrust generated between the third motor and the fourth motor.

2. The multirotor aircraft of claim 1, wherein:

a first orientation of the first motor and a second orientation of the second motor are altered due to the first rotation; and

a third orientation of the third motor and a fourth orientation of the fourth motor are altered due to the second rotation.

3. The multirotor aircraft of claim 1, wherein a yaw moment of the multirotor aircraft occurs in response to the first rotation and the second rotation.

4. The multirotor aircraft of claim 1, wherein the adjustable member comprises at least one of a spring, a leadscrew, a gear, a bearing, a swivel, a joint, metal, fiberglass, carbon fiber, plastic, or an elastomeric material.

5. The multirotor aircraft of claim 1, further comprising:

a motor coupled to the adjustable member that twists the adjustable member about the axis in response to a yaw command.

6. A multirotor aircraft, comprising:

a frame comprising a first portion and a second portion connected by an adjustable member;

the first portion including a first motor; and

a second motor, wherein a first differential thrust is generated between the first motor and the second motor; and

the adjustable member alters an orientation of the first portion of the frame with respect to a second portion of the frame about an axis, thereby causing the multirotor aircraft to yaw;

wherein the axis is transverse to axes of rotation of the first and second motors.

7. The multirotor aircraft of claim 6, wherein the first differential thrust is generated by the first motor rotating at a different speed than the second motor.

8. The multirotor aircraft of claim 6, wherein the altering the orientation occurs in response to the first differential thrust relative to a second differential thrust generated between a third motor and a fourth motor of the second portion of the frame.

9. The multirotor aircraft of claim 6, wherein the adjustable member includes an actuator that alters the orientation of the first portion of the frame with respect to the second portion of the frame.

10. The multirotor aircraft of claim 9, wherein the actuator alters the orientation in response to a yaw command.

11. The multirotor aircraft of claim 8, wherein:

the first motor and the third motor are rotating in a first direction; and

the second motor and the fourth motor are rotating in a second direction.

12. The multirotor aircraft of claim 8, wherein:

the first motor, the second motor, the third motor, and the fourth motor each rotate in a first direction.

13. The multirotor aircraft of claim 8, wherein the altering the orientation:

causes the first portion of the frame to rotate in a first direction; and

causes the second portion of the frame to rotate in a second direction.

14. The multirotor aircraft of claim 6, wherein the adjustable member includes a controller that varies a stiffness of the adjustable member.

15. The multirotor aircraft of claim 6, further comprising:

a wing; and

wherein the altering the orientation causes the wing to rotate with respect to the frame.

16. A multirotor aircraft, comprising:

a frame;

a wing; and

an adjustable member that rotates at least a portion of the wing by a first rotation in a first direction about an axis and rotates at least a portion of the wing by a second rotation in a second direction about the axis, wherein the first rotation is at least partially generated in response to a first differential thrust generated between a first motor and a second motor;

wherein the axis is transverse to axes of rotation of the first and second motors.

17. The multirotor aircraft of claim 16, wherein:

the second rotation is at least partially generated in response to a second differential thrust generated between a third motor and a fourth motor.

18. The multirotor aircraft of claim 17, further comprising:

a first motor arm coupled to a first portion of the wing, the first motor and the second motor coupled to opposing ends of the first motor arm; and

a second motor arm coupled to a second portion of the wing, the third motor and the fourth motor coupled to opposing ends of the second motor arm.

19. The multirotor aircraft of claim 16, wherein the adjustable member is the wing.

20. The multirotor aircraft of claim 16, further comprising:

an actuator coupled to the adjustable member that twists the adjustable member in response to a yaw command.