Optical System for Detecting and Displaying Aircraft Position and Environment During Landing and Takeoff

• US 20090140885A1
• Filed: 02/25/2008
• Published: 06/04/2009
• Est. Priority Date: 02/23/2007
• Status: Active Grant

• Current Assignee: Rd2, LLC
• Original Assignee: Optical Air Data Systems, LLC
• Inventors: Gatchell, Peter A., Rogers, Philip L., Mamidipudi, Priyavadan
• Granted Patent: US 7,898,435 B2
• Time in Patent Office: Days
• US Class Current: 340/977
• CPC Class Codes: G01C 23/00 Combined instruments indicating more than one navigational value, e.g. for aircraft; Combined measuring devices for measuring two or more variables of movement, e.g. distance, speed or acceleration
• CPC Class Codes: G01C 5/005 altimeters for aircraft G01C5/02, G01C5/06 take precedence
• CPC Class Codes: G01S 13/913 for landing purposes
• CPC Class Codes: G01S 17/58 Velocity or trajectory determination systems; Sense-of-movement determination systems
• CPC Class Codes: G01S 17/88 Lidar systems specially adapted for specific applications
• CPC Class Codes: G01S 17/95 for meteorological use
• CPC Class Codes: Y02A 90/10 Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

A system and method uses light signals to detect and display the position of an airborne vehicle, such as a helicopter, during takeoff or landing or low speed, low altitude operation. A transmitter on the vehicle emits light signals while an optical receiver retrieves reflected light signals. Using light detection and ranging techniques, various parameters, such as altitude, ground speed and relative wind, are calculated based on the Doppler shift within the reflected light signals. The signals are transmitted in three different directions to facilitate the measurements of different Doppler shifts. The parameters are also displayed on a screen or other visual device within the vehicle.

Claims

1. A method for detecting a position of an aircraft comprising:

transmitting a plurality of transmitted light signals;

receiving return light signals from said plurality of transmitted light signals;

detecting changes in wavelengths for said return light signals; and

determining at least two parameters based on said changes in wavelength, wherein the parameters include altitude, ground speed and relative wind.

2. The method of claim 1, wherein the transmitting includes transmitting the plurality of light signals at different angles.

3. The method of claim 1, wherein the transmitting includes emitting the plurality of light signals from a laser mounted on the airborne vehicle.

4. The method of claim 1, further comprising updating a display according to the parameters.

5. The method of claim 1, further comprising displaying the parameters inside the airborne vehicle.

6. The method of claim 1, wherein the detecting includes determining a Doppler shift from the changes in the wavelengths.

7. A method for detecting and displaying a position of an airborne vehicle, the method comprising:

receiving a plurality of light signals;

calculating a change in wavelength for each of the plurality of signals;

determining an altitude, a ground speed and a relative wind value according to the change in the wavelength for each of the plurality of signals; and

displaying the altitude, the ground speed and the relative wind in the airborne vehicle.

8. The method of claim 7, further comprising updating the altitude, the ground speed and the relative wind with newly received light signals.

9. A system for detecting a position of an airborne vehicle during landing or takeoff operations, the system comprising:

a transmitter for emitting light signals in three or more directions from the airborne vehicle;

a laser to generate the light signals;

an optical receiver to receive reflected light signals at the airborne vehicle, wherein the transmitter is offset a distance from the optical receiver;

a processor to determine changes in wavelengths of the reflected light signals and to calculate parameters for the position of the airborne vehicle, wherein the parameters include altitude, ground speed and relative wind; and

a display to show the parameters within the airborne vehicle.

10. The system of claim 9, further comprising a gyroscope to provide a reference for the transmitter and optical receiver, and to provide an angle of transmission for the light signals.