SYSTEM AND METHOD FOR CONTROLLING HIGH SPIN RATE PROJECTILES

• US 20090272839A1
• Filed: 04/30/2008
• Published: 11/05/2009
• Est. Priority Date: 04/30/2008
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Clingman, Dan J.
• Granted Patent: US 7,834,301 B2
• Time in Patent Office: Days
• US Class Current: 244/3.100
• CPC Class Codes: F42B 10/60 Steering arrangements F42B19/01 takes precedence
• CPC Class Codes: G05D 1/108 animated with a rolling movement

Abstract

A method is disclosed for controlling a flight trajectory of a spinning projectile. In one aspect the method may involve supporting a nose of the projectile in a manner permitting the nose to be wobbled. At least one electrically responsive component may be coupled at a first end to the nose and at a second end to a base portion of the projectile. An angular position of the nose of the projectile may be sensed as the projectile flies through an atmosphere after being fired from a weapon. An electrical signal is controllably applied to the electrically responsive component, in relation to the sensed angular position of the nose, to control an attitude of the nose during flight of the projectile.

Claims

1. A method for controlling a flight trajectory of a spinning projectile, comprising:

supporting a nose of said projectile in a manner permitting said nose to be wobbled relative to a base portion of the projectile;

coupling at least one electrically responsive component at a first end to said nose and at a second end to said base portion of said projectile;

sensing an angular position of said nose of said projectile as said projectile flies through an atmosphere after being fired from a weapon; and

controllably applying an electrical signal to said electrically responsive component, in relation to said sensed angular position of said nose, to control an attitude of said nose during flight of said projectile.

2. The method of claim 1, wherein said electrical signal causes said electrically responsive component to maintain said nose at a generally constant attitude relative to an external reference surface as said projectile spins during flight.

3. The method of claim 2, wherein said nose is controlled to assume a generally continuously, slightly downwardly pointed orientation relative to a ground surface over which said projectile travels.

4. The method of claim 1, wherein coupling at least one electrically responsive component to said nose comprises coupling a piezoceramic beam to said nose.

5. The method of claim 1, wherein coupling at least one electrically responsive component to said nose comprises coupling a plurality of three piezoceramic beams between said nose and said base of said projectile.

6. The method of claim 5, wherein coupling a plurality of three piezoceramic beams between said nose and said base of said projectile comprises coupling said plurality of three piezoceramic beams such that any two adjacent ones of said piezoceramic beams are circumferentially offset by about 120 degrees from one another around a perimeter of said projectile.

7. The method of claim 1, further comprising using a sensor to detect when said projectile has been fired from said weapon.

8. The method of claim 1, further controlling an amplitude of said electrical signal in relation to a sensed acceleration of said projectile.

9. A method for controlling a flight trajectory of a spinning projectile, comprising:

supporting a nose of said projectile in a manner permitting said nose to be wobbled;

supporting said nose by a plurality of circumferentially spaced apart, electrically responsive components;

detecting when said projectile has been fired from a weapon;

sensing an angular position of said nose and a rate of spin of said projectile as said projectile flies through an atmosphere after being fired from said weapon; and

controllably applying electrical signals having different phases to said plurality of electrically responsive components, in relation to said sensed angular position of said nose, to control an attitude of said nose during flight of said projectile.

10. The method of claim 9, wherein supporting said nose by a plurality of circumferentially spaced apart electrically responsive components comprises supporting said nose by a plurality of piezoceramic beams.

11. The method of claim 10, further comprising supporting said piezoceramic beams such that adjacent ones of said piezoceramic beams are arranged approximately 120 degrees from one another circumferentially about a perimeter of said projectile.

12. The method of claim 9, wherein controllably applying electrical signals comprises controllably applying electrical signals having three different phases to three different ones of said electrically responsive components.

13. The method of claim 9, further comprising sensing an acceleration of said projectile and controlling an amplitude of said electrical signals in relation to said sensed acceleration.

14. The method of claim 9, wherein sensing a rate of spin of said projectile comprises:

using an antenna carried on said projectile to receive an external electromagnetic wave signal, with a changing orientation of said antenna as said projectile spins while travelling causing said antenna to generate a periodic signal representative of a rate of rotation of said projectile; and

wherein said periodic signal is used to assist in generating said electrical signals.

15. The method of claim 14, further comprising using a reference oscillator to receive said periodic signal and to generate a sinusoidal output signal for assisting in controlling the generation of said electrical signals.

16. The method of claim 9, wherein supporting a nose of said projectile in a manner enabling said nose to be wobbled comprises supporting a nose of a bullet in a manner permitting said nose of said bullet to be wobbled.

17. A system for controlling a flight trajectory of a spinning projectile, comprising:

a projectile having a nose and a body portion, with the nose portion being supported for movement relative to the body portion;

a plurality of electrically responsive components coupled between said nose and said body portion; and

a subsystem that senses an angular position of said nose after said projectile has been fired from a weapon and generates electrical signals that are applied to said electrically responsive components to counteract said wobbling motion to maintain said nose in a relatively constant, desired attitude during flight of said projectile.

18. The system of claim 17, wherein said subsystem comprises an antenna carried on said projectile for receiving an external electromagnetic signal, said antenna generating a cyclic signal as said projectile rolls during flight, and

wherein said subsystem further includes an oscillator responsive to said cyclic signal for generating a sinusoidal electrical signal representing of a frequency of rotation of said projectile during flight of said projectile.

19. The system of claim 18, wherein said subsystem comprises an accelerometer for detecting an acceleration of said projectile;

and

an amplitude control responsive to an output of said accelerometer for adjusting an amplitude of said electrical signals applied to said electrically responsive components in accordance with a sensed acceleration of said projectile.

20. The system of claim 18, wherein said electrically responsive components each comprise piezoceramic beams that flex when receiving one of said electrical signals, said flexing adapted to deflect said nose of said projectile in a desired direction.