System and method for controlling rotorcraft

Patent metadata

Field	Value
Publication number	US-11186357-B2
Application number	US-201916238889-A
Country	US
Kind code	B2
Filing date	Jan 3, 2019
Priority date	Jan 3, 2019
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

In an embodiment, a method includes: obtaining a first signal from a first sensor of a rotorcraft, the first signal indicating measured angular velocity around a first axis of the rotorcraft; filtering the first signal with a lag compensator to estimate angular position around the first axis of the rotorcraft; and adjusting flight control devices of the rotorcraft according to the estimated angular position and the measured angular velocity around the first axis of the rotorcraft, thereby changing flight characteristics of the rotorcraft around the first axis of the rotorcraft.

First claim

What is claimed is:

1. A method comprising:
obtaining a first signal from a rate sensor of a rotorcraft, the first signal indicating measured angular velocity around a first axis of the rotorcraft;
filtering the first signal with a lag compensator to obtain an estimated angular position around the first axis of the rotorcraft;
obtaining a second signal from an absolute sensor of the rotorcraft, the second signal indicating measured angular position around the first axis of the rotorcraft, the absolute sensor being a different type of sensor than the rate sensor; and
adjusting flight control devices of the rotorcraft according to the estimated angular position and the measured angular position around the first axis of the rotorcraft, thereby changing flight characteristics of the rotorcraft around the first axis of the rotorcraft, wherein adjusting the flight control devices of the rotorcraft comprises:
executing a first flight control procedure according to the estimated angular position around the first axis of the rotorcraft, the first flight control procedure not using the measured angular position around the first axis of the rotorcraft; and
executing a second flight control procedure according to the measured angular position around the first axis of the rotorcraft, the first flight control procedure having greater authority than the second flight control procedure.

2. The method of claim 1 , further comprising:
receiving a control signal from a pilot flight control of the rotorcraft; and
adjusting the flight control devices of the rotorcraft according to the control signal, thereby changing flight characteristics of the rotorcraft around a second axis of the rotorcraft, the second axis being different from the first axis,
wherein the flight characteristics of the rotorcraft around the first axis of the rotorcraft are changed in response to changing the flight characteristics of the rotorcraft around the second axis of the rotorcraft.

3. The method of claim 1 , wherein the rate sensor is a gyroscope, and obtaining the first signal comprises:
receiving the first signal from the gyroscope.

4. The method of claim 1 , wherein the rate sensor is an accelerometer, and obtaining the first signal comprises:
receiving a transduced sensor signal from the accelerometer, the transduced sensor signal indicating angular acceleration around the first axis of the rotorcraft; and
integrating the transduced sensor signal with respect to time to obtain the first signal.

5. The method of claim 1 , wherein the estimated angular position around the first axis of the rotorcraft is estimated using only the measured angular velocity around the first axis of the rotorcraft.

6. The method of claim 1 , wherein the lag compensator has a same set of gains at all operating points of the lag compensator, the set of gains being predetermined independent of airspeed of the rotorcraft.

7. The method of claim 1 , wherein the lag compensator has different sets of gains at different operating points of the lag compensator.

8. The method of claim 1 , wherein the absolute sensor is an attitude sensor.

9. A rotorcraft comprising:
a rate sensor;
an absolute sensor, the absolute sensor being a different type of sensor than the rate sensor;
flight control devices; and
a flight control computer coupled to the rate sensor and the flight control devices, the flight control computer configured to:
obtain a first signal from the rate sensor, the first signal indicating measured angular velocity around a first axis of the rotorcraft;
filter the first signal with a lag compensator to obtain an estimated angular position around the first axis of the rotorcraft;
obtain a second signal from the absolute sensor, the second signal indicating measured angular position around the first axis of the rotorcraft; and
adjust the flight control devices according to the estimated angular position and the measured angular velocity around the first axis of the rotorcraft, thereby changing flight characteristics of the rotorcraft around the first axis of the rotorcraft, wherein the flight control computer is configured to adjust the flight control devices of the rotorcraft by:
executing a first flight control procedure according to the estimated angular position around the first axis of the rotorcraft, the first flight control procedure not using the measured angular position around the first axis of the rotorcraft; and
executing a second flight control procedure according to the measured angular position around the first axis of the rotorcraft, the first flight control procedure having greater authority than the second flight control procedure.

10. The rotorcraft of claim 9 , further comprising:
a pilot flight control, wherein the flight control computer is further configured to:
receive a control signal from the pilot flight control; and
adjust the flight control devices according to the control signal, thereby changing flight characteristics of the rotorcraft around a second axis of the rotorcraft, the second axis being different from the first axis,
wherein the flight characteristics of the rotorcraft around the first axis of the rotorcraft are changed in response to changing the flight characteristics of the rotorcraft around the second axis of the rotorcraft.

11. The rotorcraft of claim 9 , wherein the rate sensor is a gyroscope, and the flight control computer is configured to obtain the first signal by:
receiving the first signal from the gyroscope.

12. The rotorcraft of claim 9 , wherein the rate sensor is an accelerometer, and the flight control computer is configured to obtain the first signal by:
receiving a transduced sensor signal from the accelerometer, the transduced sensor signal indicating angular acceleration around the first axis of the rotorcraft; and
integrating the transduced sensor signal with respect to time to obtain the first signal.

13. The rotorcraft of claim 9 , wherein the estimated angular position around the first axis of the rotorcraft is estimated using only the measured angular velocity around the first axis of the rotorcraft.

14. The rotorcraft of claim 9 , wherein the lag compensator has a same set of gains at all operating points of the lag compensator, the set of gains being predetermined independent of airspeed of the rotorcraft.

15. The rotorcraft of claim 9 , wherein the lag compensator has different sets of gains at different operating points of the lag compensator.

16. The rotorcraft of claim 9 , wherein the absolute sensor is an attitude sensor.

17. A flight control computer comprising:
a processor; and
a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions for:
obtaining a first signal from a rate sensor of a rotorcraft, the first signal indicating measured angular velocity around a first axis of the rotorcraft;
filtering the first signal with a lag compensator to obtain an estimated angular position around the first axis of the rotorcraft;
obtaining a second signal from an absolute sensor of the rotorcraft, the second signal indicating measured angular position around the first axis of the rotorcraft, the absolute sensor being a different type of sensor than the rate sensor; and
adjusting flight control devices of the rotorcraft according to the estimated angular position and the measured angular velocity around the first axis of the rotorcraft, thereby changing flight characteristics of the rotorcraft around the first axis of the rotorcraft, wherein the inst

Assignees

• Textron Innovations Inc

Inventors

• Alfred Jillian Samantha
• Gillett Luke Dafydd
• Worsham Ii Robert Earl
• Kim Sung Kyun

Classifications

• G01C21/183

  Compensation of inertial measurements, e.g. for temperature effects · CPC title

• B64C27/57

  automatic or condition responsive, e.g. responsive to rotor speed, torque or thrust · CPC title

• B64C11/44

  electric · CPC title

• B64C13/0421

  control sticks for primary flight controls · CPC title

• B64C13/044

  operated by feet, e.g. pedals · CPC title