Method and apparatus for automatically controlling aircraft flight control trim systems

• US 8,718,839 B2
• Filed: 12/03/2010
• Issued: 05/06/2014
• Est. Priority Date: 12/06/2009
• Status: Active Grant

• Current Assignee: Evolved Aircraft Systems, LLC
• Original Assignee: Evolved Aircraft Systems, LLC
• Inventors: Everett, Michael Louis, Everett, Louis Jackson, Ruiz, Mario Jr.
• Primary Examiner(s): Black, Thomas
• Assistant Examiner(s): Lewandroski, Sara
• Application Number:
  US12/959,418
• Publication Number:
  US 20110137496A1
• Time in Patent Office: 1,250 Days
• Field of Search: 244/75.1, 244/220, 244/223, 244/178, 244/76.R, 701/3, 701/4, 701/5, 701/6, 701/7, 701/8, 701/15, 701/16, 701/11
• US Class Current: 701/3
• CPC Class Codes: B64C 13/18 using automatic pilot
• CPC Class Codes: B64C 13/22 readily revertible to personal control
• CPC Class Codes: G05D 1/0061 for transition from automatic pilot to manual pilot and vice versa

Abstract

An automatic trim system and method is disclosed for automatically trimming a flight control surface of an aircraft. A force sensor measures a force applied by a pilot to a flight control system actuator. The length of time that the force is applied by the pilot is then timed by a timer. A trim system to reduce the applied force is included on the flight control surfaces. A processor determines if trim is required if a predetermined amount of time is exceeded based on the force sensor measurement. The processor can set the trim system to the trim required therein. An airspeed sensor is used to verify that the aircraft has sufficient speed for flight. A force sensor can be utilized to measure the input force being applied by the pilot. If a pilot input force is applied to the controls and the aircraft is in a steady state, a timer can be activated. If the force sensor continues to sense a force after the timer times for a predetermined time, the trim can be adjusted in the appropriate direction until the force sensor measures no significant pilot input force.

Claims

1. An apparatus, comprising:

at least one force sensor that measures an input force applied by an operator to a control device;

a timer that measures a length of time said input force is applied during a steady state motion;

a trim system to reduce said input force applied to said control device; and

a processor that determines if trim is required due to said input force if said length of time exceeds a predetermined amount of time and wherein said processor further sets said trim system to an amount of trim required therein.

2. The apparatus of claim 1 wherein said at least one force sensor comprises at least one of a pitch axis force sensor, a roll axis force sensor or a yaw axis force sensor.

3. The apparatus of claim 1, further comprising:

at least one sensor for measuring airspeed or altitude of a vehicle comprising said apparatus.

4. The apparatus of claim 3, wherein:

said vehicle comprises an aircraft; and

said timer operates as a function of a said processor.

5. The apparatus of claim 4, further comprising:

a counter that counts applications of said input force to said control device.

6. The apparatus of claim 5, wherein said counter counts said applications if said applications of said input force is applied to said control device less than a predetermined time as measured by said timer.

7. A method, comprising:

measuring an input force applied by an operator to a control device by at least one force sensor;

timing a length of time said input force is applied during a steady state motion; and

determining if trim is required to reduce said input force applied to said control device utilizing a trim system if said length of time exceeds a predetermined amount of time and further adapted to set a trim system to an amount of trim required.

8. The method of claim 7, further comprising:

configuring said at least one force sensor to comprise at least one of a pitch axis force sensor, a roll axis force sensor or a yaw axis force sensor.

9. The method of claim 7, further comprising:

measuring at least one of airspeed or altitude of a vehicle.

10. The method of claim 9, wherein said vehicle is an aircraft and said timer is performed as a function of a processor.

11. The method of claim 10, further comprising:

counting a number of applications of said input force to said control device.

12. The method of claim 11, further comprising:

counting said number of applications via a counter, if said length of time is less than a predetermined time as measured by said timer.

13. A method, comprising:

measuring a magnitude and direction of an input force applied by an operator to an aircraft control device by at least one force sensor;

timing a length of time said input force is applied during a steady state motion utilizing a processor;

determining if trim is required due to said input force if said length of time exceeds a predetermined amount of time and setting a trim system to an amount of trim required;

counting a number of applications of said input force to said control device if said length of time does not exceed a predetermined amount of time; and

activating a trim actuator for a pre-set amount of time if said number exceeds a predetermined number of applications.

14. The method of claim 13, further comprising the step of:

setting said length of time to zero if said input force direction is in an opposite direction than an immediately subsequent measured input force.

15. The method of claim 14, further comprising the step of:

setting said number of applications to zero if said input force direction is in an opposite direction than said immediately subsequent measured input force.

16. The method of claim 13, further comprising configuring said at least one force sensor to comprise at least one of a pitch axis force sensor, a roll axis force sensor or a yaw axis force sensor.

17. The method of claim 13, further comprising the step of:

measuring at least one of airspeed or altitude of said aircraft to activate said processor if it is determined that said aircraft is in-flight based on said airspeed or said altitude.

18. The method of claim 17, further comprising the step of:

activating said trim actuator to set a trim tab of said aircraft to a takeoff setting if it is determined that said aircraft is on the ground based on said airspeed or said altitude.

19. The method of claim 17, further comprising configuring said at least one force sensor to comprise at least one of a pitch axis force sensor, a roll axis force sensor or a yaw axis force sensor.

20. The method of claim 19, further comprising the step of:

setting said number of applications to zero if said input force direction is in an opposite direction than said immediately subsequent measured input force.