Formation flying method and system

• US 10,437,261 B2
• Filed: 06/29/2011
• Issued: 10/08/2019
• Est. Priority Date: 07/01/2010
• Status: Active Grant

• Current Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Original Assignee: Sikorsky Aircraft Corporation (Martin Marietta Corporation)
• Inventors: Sahasrabudhe, Vineet, Jang, Stella, White, Matthew A.
• Primary Examiner(s): Kong, Sze-Hon
• Application Number:
  US13/172,342
• Publication Number:
  US 20120004844A1
• Time in Patent Office: 3,023 Days
• Field of Search: 701300, 701302, 701494, 701495, 701517, 701519, 701 4, 701 11
• CPC Class Codes: G05D 1/00 Control of position, course, altitude or attitude of land, water, air or space vehicles, e.g. using automatic pilots drive control systems specially adapted for autonomous road vehicles B60W60/00
• CPC Class Codes: G05D 1/0011 associated with a remote control arrangement
• CPC Class Codes: G05D 1/0022 characterised by the communication link data switching networks in general H04L12/00
• CPC Class Codes: G05D 1/0033 by having the operator tracking the vehicle either by direct line of sight or via one or more cameras located remotely from the vehicle
• CPC Class Codes: G05D 1/0038 by providing the operator with simple or augmented images from one or more cameras located onboard the vehicle, e.g. tele-operation images analyzed by a computer and used for automatic navigation G05D1/0246
• CPC Class Codes: G05D 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• CPC Class Codes: G05D 1/10 Simultaneous control of position or course in three dimensions G05D1/12 takes precedence
• CPC Class Codes: G05D 1/101 specially adapted for aircraft
• CPC Class Codes: G05D 1/104 involving a plurality of aircrafts, e.g. formation flying traffic control systems for aircraft G08G5/00
• CPC Class Codes: G08G 5/0047 Navigation or guidance aids for a single aircraft details of equipment G08G5/0017
• CPC Class Codes: G08G 5/0069 specially adapted for an unmanned aircraft
• CPC Class Codes: G08G 5/04 Anti-collision systems

Abstract

A method for directing formation flying of an aircraft includes sensing a relative position of a leader to a follower aircraft by one or more sensors disposed at the follower aircraft. The relative position is compared to a selected relative position, and a follower velocity of the follower aircraft necessary to move the follower aircraft to the selective relative position is determined via a flight control computer of the follower aircraft. The follower velocity is transformed into flight control inputs and the follower aircraft is moved to the selected relative position via the flight control inputs.

Claims

1. A method for directing formation flying of an aircraft comprising:

determining a position of a leader vehicle by one or more sensors disposed at a follower aircraft, the one or more sensors including at least one of a video sensor, a radar sensor, an infrared sensor, a sonar sensor, and a LIDAR sensor;

converting images captured by at least one of the one or more sensors into a real time estimate of position including azimuth, distance, and elevation in a sensor fusion computer in the follower aircraft;

determining a relative position, between the leader vehicle and the follower aircraft at the follower aircraft based on the one or more sensors at the follower aircraft including the estimate of position from the sensor fusion computer;

comparing the relative position to a selected relative position;

determining a follower velocity of the follower aircraft necessary to move the follower aircraft to the selected relative position between the leader vehicle and the follower aircraft via a flight control computer of the follower aircraft;

transforming the follower velocity into flight control inputs in the follower aircraft;

determining a magnitude of an error between the relative position and the selected relative position;

determining whether high gain corrective flight control inputs or low gain corrective flight control inputs needed to move the aircraft into the selected relative position;

moving the follower aircraft to maintain the selected relative position via one of the high gain corrective flight control inputs and the low gain corrective flight control inputs;

transmitting data collected from the one or more sensors at the follower aircraft to the sensor fusion computer to determine the relative position of the follower aircraft to the leader vehicle;

determining that a path of the leader vehicle is unsafe for the follower aircraft to follow; and

disengaging formation flying via the flight control computer when it is unsafe for the follower aircraft to follow the leader vehicle.

2. The method of claim 1, further comprising:

sensing a global position of the leader via a global position sensor disposed at the leader vehicle; and

transmitting the global position of the leader vehicle to the follower aircraft.

3. The method of claim 2, wherein determining the relative position between the leader vehicle and the follower aircraft includes determining the relative position based on the global position of the leader vehicle transmitted to the follower aircraft and at least one other sensor disposed at the follower aircraft.

4. The method of claim 1, wherein at least one sensor of the one or more sensors is a video sensor.

5. The method of claim 4, wherein at least two sensors are video sensors.

6. The method of claim 5, wherein the relative position is determined via triangulation.

7. The method of claim 1, wherein converting the images from the video sensor into the relative position includes utilizing a visual tracking algorithm.

8. The method of claim 1, further comprising limiting movement of the follower aircraft relative to the leader vehicle to preserve safety of the follower aircraft.

9. The method of claim 1, further comprising disengaging formation flying.

10. The method of claim 9, wherein the disengagement is via one of a pilot input to a flight control, a pilot activation of a control button or switch, or independent action of the flight control computer.

11. The method of claim 1 wherein the leader vehicle is a lead aircraft.

12. A system for directing formation flying of aircraft comprising:

one or more sensors disposed at a follower aircraft, the one or more sensors configured to determine a position of a leader vehicle, the one or more sensors including at least one of a video sensor, a radar sensor, an infrared sensor, a sonar sensor, and a LIDAR sensor;

a flight control computer disposed at the follower aircraft and in operable communication with the one or more sensors, the flight control computer configured to;

convert images captured by at least one of the one or more sensors into a real time estimate of position including azimuth, distance, and elevation in a sensor fusion computer in the follower aircraft;

determine a relative position between the follower aircraft and the leader vehicle based on the one or more sensors at the follower aircraft including the real time estimate of position from the sensor fusion computer;

compare the relative position to a selected relative position;

determine a follower velocity of the follower aircraft necessary to move the follower aircraft to the selected relative position;

transform the follower velocity into flight control inputs in the follower aircraft;

determine a magnitude of an error between the relative position and the selected relative position;

determine whether high gain corrective flight control inputs or low gain corrective flight control inputs are needed to move the aircraft into the selected relative position;

direct movement of the follower aircraft to maintain the selected relative position via one of the high gain corrective flight control inputs and the low gain corrective flight control inputs;

transmit data collected from the one or more sensors at the follower aircraft to the sensor fusion computer to determine the relative position of the follower aircraft to the leader vehicle;

determine that a path of the leader vehicle is unsafe for the follower aircraft to follow; and

disengage formation flying via the flight control computer when it is unsafe for the follower aircraft to follow the leader vehicle.

13. The system of claim 12, further comprising a datalink disposed at the follower aircraft to receive global position data of the leader vehicle.

14. The system of claim 12, wherein at least one sensor of the one or more sensors is a video sensor.

15. The system of claim 14, wherein the flight control computer is configured to convert images from the video sensor into the relative position.

16. The system of claim 14, wherein at least two sensors are video sensors.

17. A system for directing formation flying of aircraft comprising:

two or more cameras disposed at a follower aircraft, a first camera of the two or more cameras disposed at a nose of the follower aircraft and a second camera of the two or more cameras disposed at a tail of the aircraft, the two or more cameras configured to detect a position of a leader vehicle;

a flight control computer disposed at the follower aircraft and in operable communication with the two or more cameras, the flight control computer configured to;

convert images from the one or more cameras into a real time estimate of relative position including azimuth, distance, and elevation, between the follower aircraft and the leader vehicle in a sensor fusion computer in the follower aircraft;

compare the real time estimate of relative position to a selected relative position within a selected position envelope;

determine a follower velocity of the follower aircraft necessary to move the follower aircraft to maintain the selected relative position;

transform the follower velocity into flight control inputs in the follower aircraft;

determine a magnitude of an error between the relative position and the selected relative position;

determine whether high gain corrective flight control inputs or low gain corrective flight control inputs are needed to move the aircraft into the selected relative position;

direct movement of the follower aircraft to maintain the selected relative position via one of the high gain corrective flight control inputs and the low gain corrective flight control inputs;

determine that a path of the leader vehicle is unsafe for the follower aircraft to follow; and

disengage formation flying via the flight control computer when it is unsafe for the follower aircraft to follow the leader vehicle.

18. A method for directing formation flying of an aircraft comprising:

determining a position of a leader vehicle with a plurality of sensors disposed at a follower aircraft, the plurality of sensors including a video sensor, a radar sensor, an infrared sensor, a sonar sensor, and a LIDAR sensor;

converting images captured by at least two of the plurality of sensors into a real time estimate of position including azimuth, distance, and elevation in a sensor fusion computer in the follower aircraft;

determining a relative position, between the leader vehicle and the follower aircraft at the follower aircraft without receiving data from a ground station based on the real time estimate of position from the sensor fusion computer;

comparing the relative position to a selected relative position;

determining a follower velocity of the follower aircraft necessary to move the follower aircraft to the selected relative position between the leader vehicle and the follower aircraft via a flight control computer of the follower aircraft;

transforming the follower velocity into flight control inputs;

determining a magnitude of an error between the relative position and the selected relative position;

determining whether high gain corrective flight control inputs or low gain corrective flight control inputs needed to move the aircraft into the selected relative position;

changing a direction of the follower aircraft through one of the high gain corrective flight control inputs and the low gain corrective flight control inputs by converting body axis velocity vx, vy, and vz of the follower aircraft into pilot path inputs;

guiding the follower aircraft into the selected relative position by changing the direction of the follower aircraft;

determining that a path of the leader vehicle is unsafe for the follower aircraft to follow; and

disengaging formation flying via the flight control computer when it is unsafe for the follower aircraft to follow the leader vehicle.