Optical fiber assembly wrapped across gimbal axes

• US 7,304,296 B2
• Filed: 10/05/2005
• Issued: 12/04/2007
• Est. Priority Date: 10/05/2005
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Brunton, Daniel W., Knapp, David J., Hicks, Jim R., Anthony, David G., Mills, James P., Garrett, David G., Harrison, Daniel C., Anderson, Emmet R., Sunne, Wayne L., Smith, Frank E. III
• Primary Examiner(s): Luu; Thanh X.
• Assistant Examiner(s): Ko; Tony
• Application Number:
  US11/243,562
• Publication Number:
  US 20070075237A1
• Time in Patent Office: 790 Days
• Field of Search: 250/239, 250/234, 356/149, 244/3.16, 372/33
• US Class Current: 250/239
• CPC Class Codes: F41G 7/224 Deceiving or protecting means jamming or anti-jamming of radio-wave systems in general G01S7/36, G01S7/38; defense installations in general F41H11/02; chaff dispensers F42B12/70
• CPC Class Codes: F41H 13/0056 for blinding or dazzling, i.e. by overstimulating the opponent's eyes or the enemy's sensor equipment
• CPC Class Codes: G01S 7/4818 using optical fibres
• CPC Class Codes: G01S 7/495 Counter-measures or counter-counter-measures using electronic or electro-optical means

Abstract

A control mechanism pins an optical fiber assembly on and off gimbal and between gimbals to route the assembly from an off-gimbal optical source across the gimbal axis/axes to an on-gimbal optical element so that the fiber assembly moves with the rotation of the gimbals. To accommodate a relatively large range of motion, the control mechanism is suitably configured to route the fiber assembly in a “U-shaped” loop with one end pinned off-gimbal in a stationary guide track and the other end pinned on-gimbal point in a rotating guide track so that the loose fiber assembly is constrained in the concentric tracks on and off gimbal. As the gimbal rotates, the loop seats onto one guiding track and peels off of the other guiding track while always maintaining its U shape. To accommodate a relatively small range of motion in other gimbal configurations, the control mechanism is suitably configured to pin one end of the fiber assembly off-gimbal and pass the fiber assembly directly over the gimbal where it is pinned on the other side of the gimbal. In a multi-gimbal pointer, the fiber assembly preferably exhibits different mechanical stresses as it crosses the different gimbals.

Claims

1. A gimbaled optical pointer, comprising:

An outer gimbal that rotates around a first gimbal axis;

An inner gimbal that rotates around a second gimbal axis orthogonal to the first to point an optical axis in a multi-dimensional space defined by said first and second gimbal axes;

An optical element on the inner gimbal that is nominally aligned with the line-of-sight of the optical axis;

A fiber assembly including a continuous optical fiber; and

A control mechanism for routing the fiber assembly to carry light from an off-gimbal source across the first and second gimbal axes to the optical element so that the fiber assembly moves with the inner and outer gimbals as the gimbals rotate about their respective axis.

2. The pointer of claim 1, wherein said control mechanism pins the fiber assembly between said inner and outer gimbals so that the fiber assembly moves independently with the rotation of the inner and outer gimbals.

3. The pointer of claim 1, wherein the control mechanism pins in order a first portion of the fiber assembly off of the outer gimbal, a second portion of the fiber assembly on the outer gimbal, a third portion of the fiber assembly off the inner gimbal and a fourth portion of the fiber assembly on the inner gimbal and routes the fiber assembly between the first and second pinned portions and third and fourth pinned portions so that the fiber assembly maintains a radius of curvature of at least a specified minimum as the fiber assembly moves with the inner and outer gimbals, said fiber assembly having different mechanical stiffness between the first and second and the third and fourth portions.

4. The pointer of claim 1, wherein the control mechanism comprises for said outer and/or said inner gimbal an off-gimbal stationary guide track and an on-gimbal rotating guide track, said mechanism routing the fiber assembly in a U-shaped service loop with a first portion at one end of the loop pinned on the stationary guide track and a second portion at the other end of the loop pinned on-the rotating guide track so that loose fiber assembly is constrained in the concentric tracks on and off gimbal so that as the gimbal rotates the loop seats onto one guide track and peels off of the other guide track while always maintaining its U shape.

5. The pointer of claim 1, wherein the control mechanism for said outer and/or said inner gimbal pins a first portion of the fiber assembly off-gimbal and passes the fiber assembly directly over the inner gimbal where it is pinned on the other side of the inner gimbal so that the fiber assembly moves with gimbal and maintains a radius of curvature of at least a specified minimum.

6. The pointer of claim 1, wherein the control mechanism comprises for one of said outer and said inner gimbal,

an off-gimbal stationary guide track and an on-gimbal rotating guide track, said mechanism routing the fiber assembly in a U-shaped service loop with a first portion at one end of the loop pinned on the stationary guide track and a second portion at the other end of the loop pinned on-the rotating guide track so that loose fiber assembly is constrained in the concentric tracks on and off gimbal so that as the gimbal rotates the loop seats onto one guide track and peels off of the other guide track while always maintaining its U shape;

and for the other of said outer and said inner gimbal,

a first clamp that pins the fiber assembly off-gimbal and passes the fiber assembly directly over the inner gimbal where a second clamp pins it on the other side of the inner gimbal so that the fiber assembly moves with gimbal and maintains a radius of curvature of at least a specified minimum.

7. The pointer of claim 6, wherein the fiber assembly has different mechanical stiffness across said first and second gimbal axes, said assembly comprising an inner flexible jacket that covers the length of the fiber and an intermediate jacket that covers the fiber in at least the U-shaped service loop to provide additional mechanical stiffness and press the fiber into the guides.

8. The pointer of claim 7, wherein the fiber assembly further comprises an outer jacket that covers the fiber between the outer gimbal and the off-gimbal source.

9. The pointer of claim 1, further comprising a receiver on the inner gimbal along the optical axis, said optical element being offset from the optical axis.

10. The pointer of claim 1, wherein a plurality of off-gimbal light sources are optically coupled to at least one said optical element on the inner gimbal through at least one said fiber assembly.

11. The pointer of claim 1, wherein the fiber assembly comprises a plurality of jackets covering differing lengths of the fiber so that the fiber assembly exhibits different mechanical stiffness across the first and second axes.