Fly-by-wire system with FCC-integrated servo actuators

Patent metadata

Field	Value
Publication number	US-12491990-B2
Application number	US-202418612462-A
Country	US
Kind code	B2
Filing date	Mar 21, 2024
Priority date	Aug 9, 2023
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

A fly-by-wire (FBW) system comprising a plurality of servo actuators for controlling the flight control surfaces of an aircraft in which each of the servo actuators may comprise a flight control computer (FCC) that controls the output of the servo actuator. Input from a pilot or autopilot system may be communicated directly to the servo actuator FCCs, which may perform the requisite computations to determine the servo actuator output. For each axis, a primary and a secondary servo actuator may be provided, and the secondary servo actuator may operate in the event of a failure in the primary servo actuator. Each servo actuator may have two motors, each configured to drive an end of a differential such that each motor can act as a brake, a clutch or motor on the servo actuator.

First claim

The invention claimed is:

1 . A fly-by-wire system, comprising:
an input system for receiving input from a pilot; and a control system communicatively coupled to the input system, the control system comprising:
a pitch axis control comprising a primary pitch servo actuator and a secondary pitch servo actuator, wherein the primary pitch servo actuator and secondary pitch servo actuator are each coupled to at least one control surface that, when adjusted, controls a pitch axis position; and
a roll axis control comprising a primary roll servo actuator and a secondary roll servo actuator, wherein the primary roll servo actuator and secondary roll servo actuator are each coupled to at least one control surface that, when adjusted, controls the roll axis position;
wherein each of the primary pitch servo actuator, the secondary pitch servo actuator, the primary roll servo actuator, and the secondary roll servo actuator comprises a flight control computer (FCC) configured to adjust the at least one control surface to which the respective servo actuator is coupled based on the input from the input system and feedback from the corresponding control surface;
wherein the FCC on each of the primary pitch servo actuator and the secondary pitch servo actuator controls only pitch axis positioning and the FCC on each of the primary roll servo actuator and the secondary roll servo actuator controls only roll axis positioning.

2 . The fly-by-wire system of claim 1 , wherein each FCC comprises a command-monitor computing architecture having a command processing lane and a monitor processing lane, the command processing lane and the monitor processing lane distinctly programmed based on flight control laws.

3 . The fly-by-wire system of claim 2 , wherein each servo actuator comprises a first motor coupled to a first side of a differential and a second motor coupled to a second side of the differential.

4 . The fly-by-wire system of claim 3 , wherein the command processing lane controls the first motor, and the monitor processing lane controls the second motor.

5 . The fly-by-wire system of claim 1 , wherein the secondary pitch servo actuator is configured to position the at least one control surface to which it is coupled in response to a detected failure in the primary pitch servo actuator.

6 . The fly-by-wire system of claim 5 ,
wherein the control surface to which the primary pitch servo actuator is coupled is a first elevator and the control surface to which the secondary pitch servo actuator is coupled is a second elevator.

7 . The fly-by-wire system of claim 1 , wherein the FCC on the primary pitch servo actuator comprises hardware distinct from hardware on the FCC on the secondary pitch servo actuator.

8 . A control system for aircraft, comprising:
an input system, comprising:
at least one flight control device comprising at least one sensor configured to provide a pitch axis command and a roll axis command based on a first input received from a pilot;
a rudder pedal interface comprising at least one yaw axis sensor for providing a desired yaw axis command based on a second input received from the pilot;
a pitch servo actuator coupled to a first control surface that, when adjusted, controls a pitch axis position, wherein the pitch servo actuator comprises a pitch axis flight control computer (FCC) configured to:
receive first positional data from the at least one sensor indicative of the pitch axis command; and
adjust the first control surface to obtain the desired pitch axis position;
a roll servo actuator coupled to a second control surface that, when adjusted, controls a roll axis position, wherein the roll servo actuator comprises a roll axis FCC configured to:
receive second positional data from the at least one sensor indicative of the roll axis command; and
adjust the second control surface to obtain the desired roll axis position; and
a yaw servo actuator coupled to a third control surface that, when adjusted, controls a yaw axis position, wherein the yaw servo actuator comprises a yaw axis FCC configured to:
receive third positional data from the at least one yaw axis sensor indicative of the yaw axis command; and
adjust the third control surface to obtain the desired yaw axis position;
wherein the pitch axis FCC controls only pitch axis positioning, the roll axis FCC controls only roll axis positioning, and the yaw axis FCC controls only yaw axis positioning.

9 . A fly-by-wire system, comprising:
at least one input; and a control system communicatively coupled to the at least one input, comprising:
at least one pitch servo actuator comprising a pitch axis flight control computer (FCC) for adjusting an elevator based on input from the at least one input; and
at least one roll servo actuator comprising a roll axis FCC for adjusting an aileron based on input from the at least one input; and
a yaw servo actuator comprising a yaw axis FCC for adjusting a rudder based on input from the at least one input,
wherein the pitch axis FCC controls only adjustment of the elevator, the roll axis FCC controls only adjustment of the aileron, and the yaw axis FCC controls only adjustment of the rudder.

10 . The fly-by-wire system of claim 9 ,
wherein each of the at least one pitch servo actuator, the at least one roll servo actuator, and the yaw servo actuator comprises a first motor and a second motor, wherein the first motor and the second motor are coupled to respective sides of a differential for controlling a control surface.

11 . The fly-by-wire system of claim 10 , wherein the differential is a harmonic drive differential.

12 . The fly-by-wire system of claim 9 , wherein the at least one input comprises pilot input received via at least one flight control device or input from an autopilot system.

13 . The fly-by-wire system of claim 12 ,
wherein the at least one flight control device comprises a first sidestick and a second sidestick, and wherein the first sidestick and the second sidestick are mechanically coupled.

14 . The fly-by-wire system of claim 9 , wherein at least one of: the at least one pitch servo actuator, the at least one roll servo actuator, or the yaw servo actuator comprises at least one position sensor for monitoring a position thereof.

Assignees

• Garmin Int Inc

Inventors

• Kilgore Dustin B
• Patel Benjamin N
• Dinger Perry L

Classifications

• B64C13/044

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

• G05D2109/22

  with fixed wings · CPC title

• G05D1/49

  Control of attitude, i.e. control of roll, pitch or yaw · CPC title

• G05D1/87

  using redundant control arrangements · CPC title

• B64C13/503 Primary

  Fly-by-Wire · CPC title