Rotorcraft

Patent metadata

Field	Value
Publication number	US-2016280369-A1
Application number	US-201415033788-A
Country	US
Kind code	A1
Filing date	Oct 31, 2014
Priority date	Nov 1, 2013
Publication date	Sep 29, 2016
Grant date	—

Abstract

A rotorcraft having a body and a propulsion system wherein the propulsion system includes a main thrust rotor and multiple control rotors, wherein the main thrust rotor is coupled to the body, whereby the main thrust rotor is driven by a main thrust drive shaft having an axis of rotation maintained in a fixed orientation to the body of the rotorcraft and wherein the multiple control rotors are arranged to control roll, pitch and yaw of the rotorcraft and are driven by respective control drive shafts offset to the axis of rotation of the main thrust drive shaft.

First claim

1 . A rotorcraft having a body and a propulsion system wherein the propulsion system includes a main thrust rotor and multiple control rotors, wherein the main thrust rotor is coupled to the body, whereby the main thrust rotor is driven by a main thrust drive shaft having an axis of rotation maintained in a fixed orientation to the body of the rotorcraft and wherein the multiple control rotors are arranged to control roll, pitch and yaw of the rotorcraft and are driven by respective control drive shafts offset to the axis of rotation of the main thrust drive shaft.

2 . The rotorcraft of claim 1 wherein the roll, pitch and yaw of the rotorcraft are controlled by varying one or more of blade pitch, speed or orientation of the control rotors.

3 . The rotorcraft of claim 1 , wherein the main thrust rotor has collective blade pitch control.

4 . The rotorcraft of claim 1 , further including a flapping hinge associated with the main thrust rotor to assist with gyroscopic precession correction.

5 . The rotorcraft of claim 1 wherein the control rotors are in an array disposed about the axis of rotation of the main thrust drive shaft.

6 . The rotorcraft of claim 5 wherein the rotorcraft includes three control rotors.

7 . The rotorcraft of claim 6 wherein the control rotors are arranged about the axis of rotation of the main thrust drive shaft at intervals of 120°.

8 . The rotorcraft of claim 5 wherein the control rotors are arranged asymmetrically about the axis of rotation of the main thrust drive shaft.

9 . The rotorcraft of claim 1 wherein the control rotors are radially disposed from the axis of rotation of the main thrust drive shaft and are positioned above or below and within the swept area of the main thrust rotor.

10 . The rotorcraft of claim 1 wherein the control rotors are positioned in the downwash of the main thrust rotor.

11 . The rotorcraft of claim 1 wherein the control drive shafts are canted relative to the axis of rotation of the main thrust drive shaft.

12 . The rotorcraft of claim 1 wherein the orientations of the control drive shafts are fixed.

13 . The rotorcraft of claim 1 wherein the control rotors have fixed pitch blades.

14 . The rotorcraft of claim 1 wherein the thrust of the main thrust rotor is parallel to the axis of rotation of the main thrust drive shaft.

15 . The rotorcraft of claim 4 , wherein the flapping hinge is a mechanical or flexural flapping hinge included in the main thrust rotor.

16 . The rotorcraft of claim 1 having a centre of mass and wherein the main thrust rotor is positioned below the centre of mass of the rotorcraft.

17 . The rotorcraft of claim 1 wherein a controller is used to correct for rotor gyroscopic precession torques using the control rotors.

18 . The rotorcraft of claim 17 wherein the controller uses modified linear PID control with gyroscopic correction to correct for rotor gyroscopic precession torques.

19 . The rotorcraft of claim 1 wherein a feedback control system is used to stabilise the rotorcraft in flight.

20 . A method of controlling the rotorcraft of claim 1 , including manoeuvring the rotorcraft by varying one or more of the pitch, speed or orientation of one or more of the control rotors and/or a collective blade pitch of the main thrust rotor.

21 . A rotorcraft with a fixed-pitch main rotor that generates lift and torque and multiple control rotors to provide counter-torque and attitude control.

22 . The rotorcraft of claim 21 , wherein the control rotors are canted relative to the main rotor.

23 . The rotorcraft of claim 21 , wherein the control rotors are arranged to generate a component of vertical thrust to produce a manoeuvring moment for the rotorcraft.

24 . The rotorcraft of claim 23 , further including a drive system that allows independent speed control of each of the control rotors and/or the main rotor to allow for manoeuvring.

25 . The rotorcraft of claim 21 , wherein the control rotors are arranged to spin in the same direction.

26 . The rotorcraft of claim 21 , wherein the control rotors are smaller than the main rotor and have fixed pitch blades.

27 . The rotorcraft of claim 21 , wherein three control rotors are arrayed about the rotorcraft.

28 . The rotorcraft of claim 27 , wherein the control rotors are arranged about the centre of the rotorcraft at intervals of 120°.

29 . The rotorcraft of claim 27 , wherein the control rotors are arranged asymmetrically about the centre of the rotorcraft.

30 . The rotorcraft of claim 27 , wherein the control rotors are mounted on booms that project from a main body of the rotorcraft.

31 . The rotorcraft of claim 21 , wherein the main rotor defines a rotor disc area footprint that covers the control rotors.

32 . The rotorcraft of claim 21 , wherein the control rotors are positioned downstream of the main rotor.

33 . The rotorcraft of claim 21 , wherein the rotorcraft is in the form of an unmanned aerial vehicle.

34 . A rotorcraft including a main rotor that rotates on a primary plane and a plurality of control rotors, wherein each control rotor rotates on a separate control plane that is at an angle relative to the primary plane.

35 . The rotorcraft of claim 34 , wherein the angles of the control planes relative to the primary plane are fixed.

36 . The rotorcraft of claim 34 , wherein the main rotor and control rotors have fixed pitch blades.

37 . The rotorcraft of claim 34 , wherein the control rotors rotate in the same direction.

38 . The rotorcraft of claim 21 , wherein a controller is used to correct for rotor gyroscopic precession torques using the control rotors.

39 . The rotorcraft of claim 38 , wherein the controller uses modified linear PID control with gyroscopic correction to correct for rotor gyroscopic precession torques.

40 . The rotorcraft of claim 21 , wherein a mechanical or flexural flapping hinge is included in a rotor head such that the primary plane may tilt with respect to a main body of the rotorcraft.

41 . The rotorcraft of claim 21 , wherein a feedback control system is used to stabilise the rotorcraft in flight.

42 . The rotorcraft of claim 21 , wherein the main rotor is located below the main body of the rotorcraft.

43 . The rotorcraft of claim 21 , wherein a centre of mass of the rotorcraft is located between the primary plane and the control planes.

44 . A method of controlling the rotorcraft of claim 21 , including manoeuvring the rotorcraft by adjusting the relative speed of one or more of the control rotors.

45 . The method of claim 44 , wherein the adjustment of the relative speed of one or more of the control rotors causes the rotorcraft to pitch, roll or yaw.

46 . The rotorcraft of claim 1 , wherein the rotorcraft is free-flying or untethered.

Assignees

• Univ Queensland

Inventors

• Pounds Paul Edward Ian

Classifications

• A63H27/00 Primary

  Toy aircraft; Other flying toys (toys with parachutes A63H33/20) · CPC title

• B64C27/82 Primary

  characterised by the provision of an auxiliary rotor or fluid-jet device for counter-balancing lifting rotor torque or changing direction of rotorcraft · CPC title

• B64C2201/024

  Operations & Transport · mapped topic

• B64C27/43

  see-saw type, i.e. two-bladed rotor · CPC title

• B64C39/024

  of the remote controlled vehicle type, i.e. RPV · CPC title