Autonomous Flight for Flight Platforms

• US 20070228221A1
• Filed: 09/26/2005
• Published: 10/04/2007
• Est. Priority Date: 09/28/2004
• Status: Active Grant

• Current Assignee: Steadicopter Limited
• Original Assignee: Steadicopter Limited
• Inventors: Segal, Tuvia
• Granted Patent: US 7,809,480 B2
• Time in Patent Office: Days
• US Class Current: 244/177
• CPC Class Codes: B64C 13/18 using automatic pilot
• CPC Class Codes: B64C 13/505 having duplication or stand-by provisions
• CPC Class Codes: B64U 10/17 Helicopters flying platforms B64U10/13
• CPC Class Codes: B64U 2201/104 using satellite radio beacon positioning systems, e.g. GPS
• CPC Class Codes: B64U 2201/20 Remote controls
• CPC Class Codes: G05D 1/0858 specially adapted for vertical take-off of aircraft

Abstract

A method and system for autonomous or semi-autonomous flight of a flight platform with flight actuators is disclosed. The system comprises a stabilization subsystem for controlling the flight actuators to maintain stabilization of the flight platform in flight and a flight control subsystem for controlling the flight actuators to implement flight control of the flight platform in flight. The two subsystems operate separately, wherein the flight control subsystem is overridden by the stabilization subsystem in an event where the flight platform exceeds a predetermined stabilization threshold until the flight platform regains stability.

Claims

1. A system for autonomous or semi-autonomous flight of a flight platform with flight actuators, the system comprising a stabilization subsystem for controlling the flight actuators to maintain stabilization of the flight platform in flight and a flight control subsystem for controlling the flight actuators to implement flight control of the flight platform in flight, the two subsystems operating separately, wherein the flight control subsystem is overridden by the stabilization subsystem in an event where the flight platform exceeds a predetermined stabilization threshold until the flight platform regains stability.

2. The system of claim 1, wherein the stabilization subsystem comprises stability measurement sensors, the sensors providing input to a stabilization control processing unit implementing a stabilization control algorithm, the stabilization control processing unit providing stabilization outputs to the flight actuators of the flight platform.

3. The system of claim 2 wherein a self-adjusting parameter set of the stabilization control algorithm is used.

4. The system of claim 2 wherein a preset parameter set of the stabilization control algorithm is used.

5. The system of claim 1, wherein the flight control subsystem comprises flight sensors measuring flight parameters, the flight sensors providing input to a flight control processing unit implementing a flight control algorithm, the flight control processing unit providing flight control outputs to the flight actuators of the flight platform.

6. The system of claim 5 wherein the flight control algorithm calculates required magnitudes of flight control outputs and produces, for each required magnitude, a group of outputs comprising at least one of a plurality of outputs of greater magnitudes than the required magnitude, and at least one of a plurality of outputs of lesser magnitudes than the required magnitude.

7. The system of claim 6, wherein, in at least some of the groups of outputs, said at least one of a plurality of outputs of greater magnitudes precedes said at least one of a plurality of outputs of lesser magnitudes.

8. The system of claim 6 wherein the magnitudes of the lesser outputs relate by a function to the magnitudes of the greater outputs.

9. The system of claim 6 wherein the total number of outputs per group is constant.

10. The system of claim 6 wherein the total number of outputs of greater magnitudes per group is constant.

11. The system of claim 6 wherein the total number of outputs of lesser magnitudes per group is constant.

12. The system of claim 1 wherein, upon occurrence of a predefined fault in the flight control subsystem, the stabilization subsystem maintains the flight platform balanced until the flight control subsystem recovers.

13. The system of claim 12 wherein the stabilization subsystem maintains the flight platform stabilization until the flight control subsystem performs an emergency landing.

14. The system of claim 1 further provided with a ground station in communication with the flight control subsystem, whereby an operator can override the flight control subsystem with manual flight commands.

15. A method for autonomous or semi-autonomous flight of a flight platform with flight actuators, the method comprising:

providing a stabilization subsystem for controlling the flight actuators and a flight control subsystem for controlling the flight actuators, the two subsystems operating separately,

maintaining stabilization of the flight platform in flight by controlling the flight actuators using the stabilization subsystem,

implementing flight control of the flight platform in flight by controlling the flight actuators using the flight control subsystem implement flight control, and

overriding the flight control subsystem by the stabilization subsystem in an event where the flight platform exceeds a predetermined stabilization threshold until the flight platform regains stability.

16. The method of claim 15 wherein maintaining stabilization is achieved using a stabilization control algorithm with a self-adjusting parameter set.

17. The method of claim 15 wherein maintaining stabilization is achieved using a stabilization control algorithm with a preset parameter set.

18. The method of claim 15, wherein implementing flight control is carried out using a flight control algorithm that generates flight control outputs.

19. The method of claim 18 wherein the flight control algorithm calculates required magnitudes of flight control outputs and produces, for each required magnitude, a group of outputs comprising at least one of a plurality of outputs of greater magnitudes than the required magnitude, and at least one of a plurality of outputs of lesser magnitudes than the required magnitude.

20. The method of claim 19, wherein, in at least some of the groups of outputs, said at least one of a plurality of outputs of greater magnitudes precedes said at least one of a plurality of outputs of lesser magnitudes.

21. The method of claim 19 wherein the magnitudes of the lesser outputs relate by a function to the magnitudes of the greater outputs.

22. The method of claim 19 wherein the total number of outputs per group is constant.

23. The method of claim 19 wherein the total number of outputs of greater magnitudes per group is constant.

24. The method of claim 19 wherein the total number of outputs of lesser magnitudes per group is constant.

25. The method of claim 15 wherein, upon occurrence of a predefined fault in the flight control subsystem, stabilization is maintained by the stabilization subsystem until the flight control subsystem recovers.

26. The method of claim 25, wherein stabilization is maintained by the stabilization subsystem until the flight control subsystem performs an emergency landing.

27-28. -28. (canceled)