Aircraft control system

• US 20100308161A1
• Filed: 08/02/2010
• Published: 12/09/2010
• Est. Priority Date: 02/14/2000
• Status: Active Grant

• Current Assignee: Aerovironment
• Original Assignee: Aerovironment
• Inventors: Lisoski, Derek L., Kendall, Greg T., Griecci, John A., Morgan, Walter R.
• Granted Patent: US 9,120,555 B2
• Time in Patent Office: Days
• US Class Current: 244/47
• CPC Class Codes: B64C 15/02 the jets being propulsion jets
• CPC Class Codes: B64C 17/00 Aircraft stabilisation not otherwise provided for
• CPC Class Codes: B64C 3/38 Adjustment of complete wings or parts thereof
• CPC Class Codes: B64C 3/42 Adjusting about chordwise axes
• CPC Class Codes: B64C 3/52 Warping
• CPC Class Codes: B64C 39/024 of the remote controlled vehicle type, i.e. RPV
• CPC Class Codes: B64C 39/10 All-wing aircraft
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: B64D 27/353 using solar cells
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: B64U 10/25 Fixed-wing aircraft VTOL aircraft B64U10/20
• CPC Class Codes: B64U 2101/00 UAVs specially adapted for particular uses or applications
• CPC Class Codes: B64U 2101/20 for use as communications relays, e.g. high-altitude platforms
• CPC Class Codes: B64U 2101/30 for imaging, photography or videography
• CPC Class Codes: B64U 2201/20 Remote controls
• CPC Class Codes: B64U 30/12 Variable or detachable wings, e.g. wings with adjustable sweep
• 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 50/31 generated by photovoltaics
• CPC Class Codes: B64U 60/50 with landing legs
• CPC Class Codes: H04B 7/18504 : Aircraft used as relay or high altitude atmospheric platform
• CPC Class Codes: Y02T 50/10 : Drag reduction
• CPC Class Codes: Y02T 50/40 : Weight reduction
• CPC Class Codes: Y02T 50/50 : On board measures aiming to increase energy efficiency

Abstract

A span-loaded, highly flexible flying wing, having horizontal control surfaces mounted aft of the wing on extended beams to form local pitch-control devices. Each of five spanwise wing segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other wing segments, to minimize inter-segment loads. Wing dihedral is controlled by separately controlling the local pitch-control devices consisting of a control surface on a boom, such that inboard and outboard wing segment pitch changes relative to each other, and thus relative inboard and outboard lift is varied.

Claims

1. An aircraft characterized by a flight envelope, comprising:

a laterally extending wing;

a plurality of pitch-control devices, each pitch-control device being mounted at a separate lateral location along the wing, and each pitch-control device being configured to apply pitch-control torque at its lateral location, wherein the wing is characterized by a torsional flexibility high enough for each pitch-control device to substantially control localized pitch at its lateral wing location; and

a control system configured to control the plurality of pitch-control devices.

2. The aircraft of claim 1, wherein each pitch-control device includes a boom connecting the wing to a control surface aft of the trailing edge of the wing at a distance adequate to cause the control surface pitch effect to dominate the control surface flap effect.

3. The aircraft of claim 1, wherein the control system is configured to operate the pitch-control devices under a protocol that will control wing dihedral under a predetermined program.

4. The aircraft of claim 3, wherein the protocol actively provides for dihedral control to maintain the wing bending stresses within safety limits.

5. The aircraft of claim 1, and further comprising a plurality of motors, wherein the control system is configured to separably control the thrust from the plurality of motors to reduce fore-and-aft wing loads between the motors.

6. The aircraft of claim 1, wherein the pitch-control devices include both fixed and controllable horizontal surfaces.

7. The aircraft of claim 1, wherein the control system implements a protocol configured to direct the pitch-control devices to control wing dihedral.

8. The aircraft of claim 1, wherein the aircraft is controlled without the use of elevators.

9. An aircraft characterized by a flight envelope, comprising:

a laterally extending wing;

a means for separately actuating the pitch of the wing at a plurality of lateral locations along the wing, wherein the wing is characterized by a torsional flexibility high enough for the means for separately actuating to substantially actuate localized pitch at the plurality of lateral locations; and

a means for controlling the means for separately actuating.

10. A method of controlling an aircraft characterized by a flight envelope, comprising:

separately actuating the pitch of a laterally extending wing at a plurality of lateral locations along the wing, wherein the wing is characterized by a torsional flexibility high enough for the means for separately actuating to substantially actuate localized pitch at the plurality of lateral locations; and

controlling the means for separately actuating.

11. The method of claim 10, wherein the step of controlling includes directing the pitch-control devices under a protocol configured to control wing dihedral.

12. An aircraft characterized by a flight envelope, comprising:

a laterally extending wing;

a plurality of pitch-control devices configured to separately change the lift of the wing at a respective plurality of lateral locations along the wing; and

a control system configured to control the plurality of pitch-control devices, wherein the control system is configured to control the plurality of pitch-control devices using a protocol that actively controls the dihedral of the wing.