Constant vertical state maintaining cueing system

• US 7,463,956 B2
• Filed: 07/03/2003
• Issued: 12/09/2008
• Est. Priority Date: 07/03/2003
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Morse, Channing S., Einthoven, Pieter G.
• Primary Examiner(s): To; Tuan C
• Application Number:
  US10/613,253
• Publication Number:
  US 20050004721A1
• Time in Patent Office: 1,986 Days
• Field of Search: 701/4, 701/3, 701/10, 244/229, 244/17.13, 244/180, 244/178, 244/223, 244/434, 244/195, 244/182, 244/185, 244/196, 244/236, 310/975, 310/974
• US Class Current: 701/4
• CPC Class Codes: G05D 1/0858 specially adapted for vertical take-off of aircraft

Abstract

This invention relates to the concept of managing the rate of change of energy in a helicopter or other aeronautical vehicle. The invention uses energy management calculations to determine the maximum longitudinal and lateral inputs that can be made while still enabling the vehicle to maintain a desired vertical state. The results of the calculations can be cued to the pilot either tactilely, aurally, or visually, or used for internal software limiting.

Claims

1. A method for determining the maximum acceleration limits for the longitudinal or lateral axis of an aeronautical vehicle while maintaining a constant vertical state, said vehicle having a vertical control inceptor, said method comprising:

determining at least one vertical inceptor position required to maintain a vertical state via a controller, wherein said at least one vertical inceptor position is a predicted position based on vehicle performance and operator inputs;

determining maximum allowable vertical inceptor position limits for desired operation of the vehicle that allow maintaining said vertical state; and

determining the maximum acceleration limits for the longitudinal or lateral axis corresponding to the maximum allowable vertical inceptor position limits.

2. The method as stated in claim 1 wherein said maximum acceleration limits are pitch and/or roll attitude limits.

3. The method as stated in claim 1 wherein said maximum acceleration limits are predicted increases or decreases in pitch and/or roll attitude limits.

5. The method as stated in claim 1 wherein said maximum acceleration limits are provided as tactile cues.

6. The method as stated in claim 1 wherein said maximum acceleration limits are provided through an active force cueing system.

7. The method as stated in claim 1 wherein said maximum acceleration limits are cued through an aural, visual or tactile cueing system.

8. The method as stated in claim 1 wherein said maximum acceleration limits are provided to a software limiting system.

9. The method as stated in claim 1 wherein said maximum acceleration limits are based on the transfer of potential and kinetic energy.

10. The method as stated in claim 1 wherein said maximum acceleration limits are based on the potential change in vertical velocity.

11. The method as stated in claim 1 wherein said maximum acceleration limits are determined using at least two methods, and the most restrictive result from the two methods are utilized.

12. The method as stated in claim 1 wherein said vertical state is holding constant vertical altitude.

13. The method as stated in claim 1 wherein said vertical state is holding constant vertical velocity.

14. The method as stated in claim 1 wherein said vertical state is holding constant flight path angle.

15. The method as stated in claim 1 wherein said maximum acceleration limits are determined by the rotor torque required to balance the gravitational forces for non-zero pitch or roll attitude.

16. The method as stated in claim 1 wherein said at least one vertical inceptor position is further based on a feedback loop of error between the desired vertical state and the measured performance.

17. The method as stated in claim 1 wherein said maximum vertical inceptor position limits are based on feedback between known limits and measured performance.

18. The method as stated in claim 1 wherein said maximum vertical inceptor position limits are based on one or more of the following group comprising:

transmission torque, engine torque, main rotor torque, main rotor overspeed, main rotor underspeed, main rotor stall, encroachment upon vortex ring state conditions, encroachment upon power setting condition, vertical velocity limits, actuator position limits and actuator rate limits.

19. The method as stated in claim 1 wherein said maximum vertical inceptor position limits are based on predictions of vehicle performance.

4. The method as stated in claim l wherein said maximum acceleration limits are represented as control inceptor position limits.

20. The method of cueing a vehicle operator of maximum accelerations and decelerations that may be performed during a constant vertical state without disengagement therefrom comprising:

generating an airspeed signal;

generating an attitude signal;

generating a vertical velocity signal;

generating a torque signal;

determining at least one vertical inceptor position to maintain a vertical state in response to said vertical velocity signal and said torque signal; and

generating a cueing signal to maintain a constant vertical state in response to said airspeed signal, said attitude signal, a minimum inceptor position, and a maximum inceptor position.

21. The method as in claim 20 further comprising:

determining the amount of vertical velocity change in response to changes in inceptor position;

determining the amount of torque change in response to changes in inceptor position; and

generating said cueing signal to maintain the constant vertical state in response to said amount of vertical velocity change and said amount of torque change.

22. A method as in claim 20 further comprising:

generating a control inceptor position signal; and

generating said cueing signal to maintain the constant vertical state in response to said control inceptor position signal.

23. A method as in claim 20 wherein generating a cueing signal comprises determining a maximum change in pitch attitude and a maximum change in roll attitude using conservation of energy based relationships.

24. A method as in claim 20 wherein generating a cueing signal comprises determining a maximum change in pitch attitude and a maximum change in roll attitude using thrust and gravitational force based relationships.

25. A method as in claim 20 wherein generating a cueing signal comprises:

determining a first maximum change in pitch attitude and a first maximum change in roll attitude using a conservation of energy relationship;

determining a second maximum change in pitch attitude and a second maximum change in roll attitude using a thrust and gravitational force based relationship;

comparing said first maximum change in pitch attitude to said second maximum change in pitch attitude and cueing which ever maximum change in pitch attitude that is smaller in magnitude; and

comparing said first maximum change in roll attitude to said second maximum change in roll attitude and cueing which ever maximum change in roll attitude that is smaller in magnitude.

26. A method as in claim 20 wherein when generating a cueing signal a minimum nose down pitch attitude for traveling velocities less than a predetermined velocity is used.

27. A method as in claim 20 wherein when generating a cueing signal a negative maximum acceleration limit is used when a current flight path angle has caused a vertical maneuvering limit to be exceeded.