Method and apparatus for remotely controlling and stabilizing unmanned aircraft

• US 8,000,849 B2
• Filed: 10/27/2006
• Issued: 08/16/2011
• Est. Priority Date: 10/27/2005
• Status: Expired due to Fees

• Current Assignee: Iron Bird LLC (Jeffrey M. Gross)
• Original Assignee: Stefan Reich
• Inventors: Reich, Stefan
• Primary Examiner(s): Camby; Richard M.
• Application Number:
  US12/084,019
• Publication Number:
  US 20090171516A1
• Time in Patent Office: 1,754 Days
• Field of Search: 701/3, 701/4, 701/10, 701/11, 701/14, 701/5, 244/75.1, 244/175, 244/181, 244/189, 244/194
• US Class Current: 701/14
• CPC Class Codes: B64C 13/20 using radiated signals
• CPC Class Codes: B64C 27/04 Helicopters
• CPC Class Codes: G05D 1/0858 specially adapted for vertical take-off of aircraft

Abstract

An aid for remotely controlling unmanned aircraft and particular helicopters, which allow the pilot at least approximately to directly stir the angle of inclination, thus for instance a pitch(elevator) and/or roll angle, so that on neutralizing of the steering stick, the respective angle of attitude returns autonomously, and to a large extent goes back to the horizontal position. To this end, a closed-loop control of the inclination is carried out, in that an angular rate signal is being integrated to an actual value, and a nominal value is admixed behind the forming of the integral, wherein the time of integration is shortened in order to avoid null drifts, in particular by feeding a portion of the actual value and/or the nominal value back into the input of the integrator. Furthermore, a vectorial rotation of the integrated actual values by a yaw signal.

Claims

1. A method for controlling an unmanned remote controlled airborne object capable of hovering comprising the steps of:

generating a steering signal formed by a pilot using a pickup unit and wherein for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object when the pickup unit is neutralized;

generating at least one rotation signal of an angular rate of at least one of an inclination pitch (elevator) and roll is formed, the at least one rotation signal is integrated with respect to time using an integrator, and the integral is being drawn upon, within the scope of a closed-loop-control, as an actual value of an angle of inclination, and a steering signal is being drawn upon as a nominal value of an inclination angle, and the difference between the actual value and the nominal value is transferred to an actuator unit controlling the flight attitude, and

wherein the duration of the integration time is narrowed down accordant to a defined time constant or accordant to a defined time window.

2. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

the measured signal of an angular rate sensor for at least one of the inclination axes roll and pitch (elevator) is used as a rotation signal.

3. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 2, wherein:

at least in one mode of operation, no further attitude measuring instruments are used.

4. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

the narrowed-down time of integration is implemented by mixing a defined small portion of at least one of the values actual value and nominal value in opposite sense into the input of the integrator, so that the integral can discharge over a longer time duration.

5. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

the integration with narrowed-down integration time is implemented by consecutively storing measured values in buffer memory cells and by consecutively forming a mean value from a defined number of stored and in particular weighed values.

6. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

the narrowed-down integration time is longer than the duration of common attitude deflections.

7. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

an adjustment of the defined time constant is adapted so that with the airborne object held fix, after a nonrecurring giving and terminating of a steering deflection of common duration, an integral value, starting from a zero value, has a value of little influence on a control point in comparison with a portion of the steering signal in the control point.

8. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

by means of a yaw rotation signal signalizing at least approximately the yaw rotations of the airborne object, the signals are, as arithmetic values, subject to a vectorial rotation, wherein the angle of rotation is controlled by the rotation signal.

9. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

the integration of the angular rate signal of the inclination is carried out in that a vectorial coordinate system is continually rotated arithmetically in an incremental way with an angular rate of an inclination.

10. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, wherein:

a difference between the steering signal and the integrated signal is subject to the integration, thus the steering signal given by the pilot is subject to a high-pass-filtering, and

wherein the high pass filtering contains no measured-signal originating from measuring instruments, the high-pass-filtered signal is forwarded or at least in part admixed to the control signal provided for driving actuators.

11. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 1, further comprising the step of:

performing the steps with a computer software product containing a program code loaded on a micro processor.

12. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 11 wherein:

an essential part of the program code allows being embedded into an existing flight stabilizing device.

13. A method for controlling an unmanned remote controlled airborne object capable of hovering according to claim 11 wherein:

an essential part of the program code allows being embedded into a programmable radio transmitter.

14. A device for flight stabilising of an unmanned and remote controllable airborne object and for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object, comprising:

an angular rate sensor for at least one of the inclination axes roll and pitch (elevator),

an integrator for a measured signal from said angular rate sensor, and

an electronic circuit suitable adapted to mix a steering signal given by the pilot as a nominal-value, next to an integral of the measured signal as an actual value of an inclination angle, or to form a difference between the nominal value and actual value,

wherein the duration of the integration time is narrowed down according to a defined time constant or a defined time window.

15. A device for flight stabilising of an unmanned and remote controllable airborne object and for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object, according to claim 14 further comprising:

a signal connection with a rotation signal signalising at least approximately the yaw movements of the airborne object, and that the apparatus is adapted to subject its arithmetic values to a vectorial rotation,

wherein the angle of rotation is controlled by the rotation signal.

16. A device for flight stabilising of an unmanned and remote controllable airborne object and for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object, according to claim 14 wherein:

the time constant or time window is adapted so that with the aircraft held fix, after the nonrecurring giving and terminating of a steering deflection of common duration, the integral value, starting from a zero value, has a value of little influence on the control point in comparison with the portion of the steering signal in the control point.

17. A device for flight stabilising of an unmanned and remote controllable airborne object and for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object, according to claim 14 wherein:

at least in one mode of operation, no further attitude measuring instruments are used.

18. A device for flight stabilising of an unmanned and remote controllable airborne object and for achieving at least in part an automatic restoring of the horizontal attitude of the airborne object, according to claim 14 wherein:

the device is structurally unified with an unmanned aircraft.

19. Method for flight stabilization of an unmanned remote controlled airborne object capable of hovering, in particular rotary wing aircraft, using an angular rate sensor for at least one of the inclination axes roll and pitch (elevator) whose measured signal is integrated with respect to time, characterized in that:

a steering signal given by the pilot, hereinafter referred to as nominal value, is admixed next to the integral of the measured signal or subject to a difference formed with the integral of the measured signal, said measured signal hereinafter referred to as actual value;

furthermore characterized in that the duration of the integration time is narrowed down accordant to a defined time constant or accordant to a defined time window,

wherein the time constant or time window is longer than the time of common steering deflections.