Distributed laser obstacle awareness system

• US 20030043058A1
• Filed: 03/28/2002
• Published: 03/06/2003
• Est. Priority Date: 09/04/2001
• Status: Active Grant

• Current Assignee: Rosemount Aerospace, Inc. (Rtx Corporation)
• Original Assignee: Rosemount Aerospace, Inc. (Rtx Corporation)
• Inventors: Ray, Mark D., Jamieson, James R.
• Granted Patent: US 6,665,063 B2
• Time in Patent Office: Days
• US Class Current: 340/961
• CPC Class Codes: B64D 45/08 optical
• CPC Class Codes: G01C 23/005 Flight directors indicating arrangements specially adapted for rotary gyroscopes G01C19/32
• CPC Class Codes: G01P 5/26 by measuring the direct influence of the streaming fluid on the properties of a detecting optical wave
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems
• CPC Class Codes: G01S 17/87 Combinations of systems using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/933 of aircraft or spacecraft
• CPC Class Codes: G01S 7/4812 transmitted and received beams following a coaxial path
• CPC Class Codes: G01S 7/4813 Housing arrangements
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: G01S 7/4818 using optical fibres
• CPC Class Codes: G01S 7/483 Details of pulse systems
• CPC Class Codes: G01S 7/486 Receivers
• CPC Class Codes: G01S 7/51 Display arrangements

Abstract

A distributed laser based obstacle awareness system for use on-board an aircraft comprises: a plurality of obstacle detecting sensors disposable at a corresponding plurality of locations of the aircraft for emitting laser energy from the aircraft into a predetermined region of space and for receiving return laser energy from an obstacle in the predetermined region of space; a laser source for emitting a laser beam along an optical path; and a plurality of bistatic optical channels. Each channel comprises a plurality of transmission fiber optic cables and at least one receiver fiber optic cable and extends from the laser source to a corresponding obstacle detecting sensor of the plurality to direct the laser beam from the optical path to its corresponding obstacle detecting sensor of the plurality for emission into the corresponding predetermined region of space; and a light detector. Return laser energy from an obstacle received by any one of the obstacle detecting sensors is propagated through the receiver fiber optic cable of the corresponding optical channel to the light detector for use in detection of the obstacle in the corresponding predetermined region of space. In one embodiment, an optical switch is disposed in the optical path to redirect the laser beam in a time sequence manner from the optical path to selected optical channels of the plurality.

Claims

1. A distributed laser based obstacle awareness system for use on-board an aircraft, said system comprising:

a plurality of obstacle detecting sensors disposable at a corresponding plurality of locations of said aircraft for emitting laser energy from the aircraft into a predetermined region of space and for receiving return laser energy from an obstacle in said predetermined region of space;

a laser source for emitting a laser beam along an optical path;

a plurality of bistatic optical channels, each channel comprising a plurality of transmission fiber optic cables and at least one receiver fiber optic cable, each optical channel extending from said laser source to a corresponding obstacle detecting sensor of said plurality, said transmission fiber optic cables of each optical channel operative to direct the laser beam from the optical path to its corresponding obstacle detecting sensor of the plurality for emission into the corresponding predetermined region of space; and

a light detector, return laser energy from an obstacle received by any one of the obstacle detecting sensors being propagated through the receiver fiber optic cable of the corresponding optical channel to the light detector for use in detection of the obstacle in the corresponding predetermined region of space.

2. The system of claim 1 wherein each obstacle detecting sensor of said plurality is flush mounted to the fuselage of the aircraft.

3. The system of claim 2 wherein each obstacle detecting sensor of said plurality includes a window which is flush mounted to the fuselage of the aircraft and through which laser energy is emitted and received.

4. The system of claim 1 wherein the transmission and receiver fiber optic cables of each optical channel are bundled together.

5. The system of claim 4 wherein the plurality of transmission fiber optic cables are bundled about the at least one receiver fiber optic cable in each optical channel at the corresponding obstacle detecting sensor.

6. The system of claim 5 wherein the receiver fiber optic cables of the channel are separated from their bundled channels away from the obstacle detecting sensors and bundled together to direct return laser energy to the light detector.

7. The system of claim 6 including an optical return signal combiner for focusing the return laser energy from the bundled receiver fiber optic cables to the light detector.

8. The system of claim 1 wherein each obstacle detecting sensor includes an optical scanner for scanning laser energy from the aircraft into a predetermined region of space in accordance with a predetermined pattern.

9. The system of claim 8 wherein the optical scanner comprises a resonant scanner.

10. The system of claim 1 wherein each obstacle detecting sensor includes an optical element for collimating the laser beam received over the corresponding transmission fiber optic cable.

11. The system of claim 1 wherein each obstacle detecting sensor includes an optical element for expanding the beam diameter of the laser beam received over the corresponding transmission fiber optic cable.

12. The system of claim 1 wherein each obstacle detecting sensor includes an optical element for focusing the received return laser energy to the corresponding receiver fiber optic cable.

13. The system of claim 1 including an optical switch disposed in the optical path between the laser source and plurality of optical channels, said optical switch operative to direct the laser beam in a time sequence manner from said optical path to selected optical channels of the plurality.

14. The system of claim 13 wherein the optical switch comprises a switch selected from the group consisting of a mechanical scanner, a resonant scanner, a MEMS scanner and a fiber optic switch.

15. A distributed laser based obstacle awareness system for use on-board an aircraft, said system comprising:

a plurality of obstacle detecting sensors disposable at a corresponding plurality of locations of said aircraft for emitting laser energy from the aircraft into a predetermined region of space and for receiving return laser energy from an obstacle in said predetermined region of space;

a laser source for emitting a laser beam along an optical path;

an optical switch disposed in said optical path;

a plurality of bistatic optical channels, each channel comprising a plurality of transmission fiber optic cables and at least one receiver fiber optic cable, each optical channel extending from said optical switch to a corresponding obstacle detecting sensor of said plurality;

said optical switch operative to redirect the laser beam in a time sequence manner from said optical path to selected optical channels of the plurality, said laser beam being propagated through the plurality of transmission fiber optic cables of the selected optical channel to the corresponding obstacle detecting sensor for emission into the corresponding predetermined region of space; and

a light detector, return laser energy from an obstacle in the corresponding predetermined region of space received by the corresponding obstacle detecting sensor and therefrom propagated through the receiver fiber optic cable of the selected optical channel to the light detector for use in detection of the obstacle in the corresponding predetermined region of space.

16. The system of claim 15 wherein the optical switch is operative to redirect the laser beam in a time sequence manner from said optical path to all of the optical channels of the plurality.

17. The system of claim 15 wherein each obstacle detecting sensor of said plurality is flush mounted to the fuselage of the aircraft.

18. The system of claim 15 wherein the transmission and receiver fiber optic cables of each optical channel are bundled together.

19. The system of claim 18 wherein the receiver fiber optic cables of the channel are separated from their bundled channels away from the obstacle detecting sensors and bundled together;

and including an optical return signal combiner for focusing the return laser energy from the bundled receiver fiber optic cables to the light detector.

20. The system of claim 15 wherein each obstacle detecting sensor includes an optical scanner for scanning laser energy from the aircraft into a predetermined region of space in accordance with a predetermined pattern.