INVERTIBLE AIRCRAFT

• US 20140138477A1
• Filed: 09/23/2013
• Published: 05/22/2014
• Est. Priority Date: 03/22/2011
• Status: Active Grant

• Current Assignee: Aerovironment
• Original Assignee: Aerovironment
• Inventors: Keennon, Matthew Todd, Klingebiel, Karl Robert
• Granted Patent: US 9,199,733 B2
• Time in Patent Office: Days
• US Class Current: 244/17.23
• CPC Class Codes: B64C 11/20 Constructional features
• CPC Class Codes: B64C 11/32 mechanical
• CPC Class Codes: B64C 2027/4733 Rotor blades substantially made from particular materials
• CPC Class Codes: B64C 27/04 Helicopters
• CPC Class Codes: B64C 27/06 with single rotor
• CPC Class Codes: B64C 27/08 with two or more rotors
• CPC Class Codes: B64C 27/12 Rotor drives
• CPC Class Codes: B64C 27/473 Constructional features
• CPC Class Codes: B64C 27/59 mechanical
• CPC Class Codes: B64C 29/0033 the propellers being tiltable relative to the fuselage
• CPC Class Codes: B64C 39/02 characterised by special use
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64C 39/028 Micro-sized aircraft
• CPC Class Codes: B64D 31/00 Power plant control systems; Arrangement of power plant control systems in aircraft
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: B64U 10/10 Rotorcrafts
• CPC Class Codes: B64U 10/13 Flying platforms
• CPC Class Codes: B64U 10/14 with four distinct rotor axes, e.g. quadcopters
• CPC Class Codes: B64U 2101/00 UAVs specially adapted for particular uses or applications
• CPC Class Codes: B64U 2101/30 for imaging, photography or videography
• CPC Class Codes: B64U 2101/31 : for surveillance
• CPC Class Codes: B64U 2101/70 : for use inside enclosed spaces, e.g. in buildings or in vehicles
• 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 30/299 : Rotor guards ducted or shrouded rotors B64U30/26; guards used as ground propulsion B64U60/60
• CPC Class Codes: B64U 50/19 : using electrically powered motors
• CPC Class Codes: G05D 1/0038 : by providing the operator with simple or augmented images from one or more cameras located onboard the vehicle, e.g. tele-operation images analyzed by a computer and used for automatic navigation G05D1/0246
• CPC Class Codes: G05D 1/005 : by providing the operator with signals other than visual, e.g. acoustic, haptic

Abstract

A rotorcraft including a fuselage, one or more motor-driven rotors for vertical flight, and a control system. The motors drive the one or more rotors in either of two directions of rotation to provide for flight in either an upright or an inverted orientation. An orientation sensor is used to control the primary direction of thrust, and operational instructions and gathered information are automatically adapted based on the orientation of the fuselage with respect to gravity. The rotors are configured with blades that invert to conform to the direction of rotation.

Claims

1. A rotorcraft, comprising:

a fuselage defining a vertical dimension with respect to the fuselage;

one or more rotors generally oriented for vertical thrust with respect to the fuselage;

one or more motors configured to drive the one or more rotors in rotation; and

a control system configured to control the speed with which the one or more motors drives the one or more rotors in rotation;

wherein the one or more motors are configured to drive the one or more rotors in either of two directions of rotation; and

wherein the control system is configured to control the one or more motors such that it can change a primary direction of thrust with respect to the fuselage developed by the one or more of rotors.

2. The rotorcraft of claim 1, wherein the control system is configured to control the primary direction of thrust with respect to the fuselage based on the orientation of the fuselage with respect to gravity.

3. The rotorcraft of claim 1, and further comprising an orientation sensor configured to sense the orientation of the fuselage with respect to gravity, wherein the control system is configured to control the primary direction of thrust with respect to the fuselage based on a signal from the orientation sensor.

4. The rotorcraft of claim 1, wherein the control system is configured to coordinate the operation of the rotors to accomplish controlled flight, and wherein the control system is configured to adapt its coordination of the rotors based on the primary direction of thrust with respect to the fuselage.

5. The rotorcraft of claim 1, and further comprising a directional sensor configured to sense the external environment, wherein the control system is configured to adjust a sensor signal from the directional sensor based on the primary direction of thrust with respect to the fuselage.

6. The rotorcraft of claim 5, and further comprising a ground station configured to depict a video signal from the directional sensor, wherein the ground station is adapted to display the video signal in an orientation based on the orientation of the fuselage with respect to gravity.

7. The rotorcraft of claim 1, wherein each rotor has a plurality of blades, and wherein each blade is configured to produce equal thrust in either direction of rotation for a given rotational speed.

8. The rotorcraft of claim 7, wherein each blade extends out from a rotor hub along a longitudinal blade axis, and wherein each blade has 2-fold rotational symmetry around its longitudinal axis.

9. The rotorcraft of claim 7, wherein each rotor has a plurality of blades, and wherein each blade includes a section of sailcloth.

10. The rotorcraft of claim 1, and further comprising a surface-connection device configured to allow the rotorcraft to affix itself to a surface such that it hangs from the surface without rotor activity to maintain its position.

11. A method of gathering intelligence prior to entering a room, comprising:

a) delivering the rotorcraft of claim 1 into the room;

b) adapting the rotorcraft to have a primary direction of thrust based on the orientation of the rotorcraft with respect to gravity once it has come to rest in the room;

c) instructing the rotorcraft to fly; and

d) scanning the room using a sensor on the rotorcraft to gather intelligence.

12. The method of claim 11, and further comprising restarting steps (b) through (d) if the flight of the rotorcraft is interrupted prior to the completion of steps (b) through (d).

13. The method of claim 11, and further comprising instructing the rotorcraft to fly to one or more additional rooms, and scanning the one or more additional rooms using the sensor to gather further intelligence.

14. The method of claim 11, and further comprising affixing the rotorcraft to hang from a surface in a position and orientation in which the sensor can provide continuing information, and continuing to scan using the sensor to gather further intelligence.

15. The method of claim 11, and further comprising:

instructing the rotorcraft to fly to one or more additional rooms, and scanning the one or more additional rooms using the sensor to gather further intelligence;

affixing the rotorcraft to hang from a surface in a position and orientation in which the sensor can provide continuing information, and continuing to scan using the sensor to gather further intelligence; and

restarting the steps at step (b) if the flight of the rotorcraft is interrupted prior to the completion of the method.

16. The method of claim 11, wherein steps (a) to (d) are conducted in sequential order.

17. An aerial vehicle, comprising:

a body;

one or more thrusters configured to provide thrust in a primary direction of thrust with respect to the body;

a control system configured to control the primary direction of thrust with respect to the body in which the one or more thrusters provides thrust; and

an orientation sensor configured to sense the orientation of the body with respect to gravity;

wherein the control system is configured to control the primary direction of thrust with respect to the body based on a signal from the orientation sensor that indicates the orientation of the body with respect to gravity.

18. A rotor for use with a motor with a shaft configured to drive the rotor in either of two opposite directions of rotation, comprising:

one or more blades, each blade having a longitudinal blade axis;

an inversion mechanism configured to rotate each of the one or more blades around its longitudinal blade axis between a first position oriented for efficient thrust in a first direction parallel to the two directions of motor rotation, and a second position oriented for efficient thrust in a second direction parallel to the two directions of rotation of the motor, the first and second directions of thrust being in opposite directions.

19. The rotor of claim 18, wherein the orientation of each blade around its blade axis in the first position is substantially 180 degrees different from the orientation of that blade in the second position.

20. The rotor of claim 18, wherein the inversion system includes:

a first gear attached to the blades;

a second gear attached to the motor shaft, wherein the first gear is meshed with the second gear; and

one or more stops configured to limit the relative movement of the first gear with respect to the second gear.

21. The rotor of claim 18, wherein the inversion system includes a cable affixed to and wrapped around the motor shaft in a configuration that drives the blades to the first position when the motor shaft rotates in the first direction, and that drives the blades to the second position when the motor shaft rotates in the second direction.