Aircraft control system and method

Patent metadata

Field	Value
Publication number	US-10983534-B2
Application number	US-201916708367-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Dec 7, 2018
Publication date	Apr 20, 2021
Grant date	Apr 20, 2021

Abstract

The unified command system and/or method includes an input mechanism, a flight processor that receives input from the input mechanism and translates the input into control output, and effectors that are actuated according to the control output. The system can optionally include: one or more sensors, a vehicle navigation system which determines a vehicle state and/or flight regime based on data from the one or more sensors, and a vehicle guidance system which determines a flightpath for the aircraft.

First claim

We claim:

1. A command method for a fly-by-wire (FBW) tiltrotor aircraft, the method comprising:
providing the FBW tiltrotor aircraft, wherein a load distribution of the FBW tiltrotor aircraft generates a first net moment about a roll axis; wherein the load distribution of the FBW tiltrotor aircraft generates a second net moment about a pitch axis, the FBW tiltrotor aircraft comprising a plurality of effectors comprising:
at least three rotors comprising a left rotor and a right rotor; and
for each of the at least three rotors, a tilt mechanism configured to transform the rotor between a forward configuration and a hover configuration;

determining a flight regime of the FBW tiltrotor aircraft, comprising one of:
a forward regime, associated with arrangement of the at least three rotors in the forward configuration; and
a hover regime, associated with arrangement of the at least three rotors in the hover configuration;

receiving a set of input commands from a user at an inceptor, the set of input commands comprising: a first, second, third, and fourth angular position on a first, second, third, and fourth axis of the inceptor, respectively;
based on the flight regime of the FBW tiltrotor aircraft, transforming the set of input commands into a set of desired aircraft responses, wherein:
the first angular position maps to a desired pitch response in the forward regime and a desired vertical translation response in the hover regime;
the second angular position maps to a desired speed response in the forward regime and a desired longitudinal translation response in the hover regime;
the third angular position maps to a desired lateral translation response in the hover regime; and

 the fourth angular position maps to a desired heading rate response in the hover regime;
based on the set of desired aircraft responses, determining a control output for the plurality of effectors of the FBW tiltrotor aircraft; and
executing the control output by actuating at least one of the plurality of effectors.

2. A command method for an aircraft, comprising:
determining a flight regime of the aircraft, the flight regime determined from a set of flight regimes comprising: a forward regime and a hover regime;
receiving a set of input commands from a user at a first input mechanism, the set of input commands comprising: a first, second, and third angular position on a first axis, second axis, and third axis of the first input mechanism, respectively;
based on the flight regime of the aircraft, mapping the set of input commands into a set of desired aircraft responses, wherein:
the first angular position maps to a desired pitch response in the forward regime and a desired vertical translation response in the hover regime;
the second angular position maps to a desired speed response in the forward regime and a desired longitudinal translation response in the hover regime; and

 the third angular position maps to a desired heading rate response in the hover regime and a desired roll response in the forward regime;
based on the set of desired aircraft responses, determining a control output; and
executing the control output by actuating a set of effectors of the aircraft, wherein the set of effectors comprises a rotor.

3. The method of claim 2 , wherein mapping the set of input commands into the set of desired aircraft responses further comprises:
trimming a desired aircraft response of the set of desired aircraft responses, wherein the desired aircraft response is dependent on an actuation state of a set of rotors and an actuation state of a set of control surfaces.

4. The method of claim 3 , wherein:
a lateral weight distribution generates a net moment about roll axis of the aircraft, wherein the desired aircraft response is a roll angle;
the set of rotors further comprises a left rotor and a right rotor, wherein executing the control output comprises different thrust outputs of the left and right rotors in the hover regime;
the set of control surfaces further comprises a left aileron and a right aileron; and
an angle of the left control surface is different from an angle of the right control surface in the forward regime.

5. The method of claim 3 , wherein the desired aircraft response comprises a deck attitude of the aircraft while the aircraft is airborne, wherein the deck attitude comprises: a lateral angle relative to the ground and a longitudinal angle relative to the ground.

6. The method of claim 3 , wherein the set of effectors further comprises a blade pitch mechanism.

7. The method of claim 2 , further comprising:
receiving a geographic-brake input from the user at the input mechanism in the forward regime; and
in response to receiving the geographic-brake input, sending a geographic-brake command to a control engine of the aircraft, the geographic-brake command associated with a desired slowing of the aircraft to zero-velocity relative to the ground.

8. The method of claim 2 , wherein:
the first axis of the input mechanism defines a first angular displacement range and a second angular displacement range, the first angular displacement range separate and distinct from the second angular displacement range; and
in the hover regime, the first angular displacement range translates to a rate of change of a degree of freedom of the aircraft and the second angular displacement range maps to a desired acceleration.

9. The method of claim 2 , further comprising:
calculating a performance protection envelope;
determining that the control output lies outside the performance protection envelope; and
shifting the control output into the performance protection envelope.

10. The method of claim 9 , further comprising: sensing the altitude of the aircraft with a time-of-flight sensor, wherein in the hover regime: the performance protection envelope comprises a maximum vertical descent rate determined based on the altitude of the aircraft.

11. The method of claim 2 , wherein in the hover regime:
a negative value for the first angular position relative to a neutral position on the first axis maps to an altitude rate toward the ground; and
a positive value for the first angular position relative to the neutral position on the first axis maps to a rate of change of the altitude rate away from the ground.

12. The method of claim 2 , wherein the third angular position further maps to a desired heading response in the forward regime.

13. The method of claim 2 , wherein:
the set of flight regimes further comprises a transition regime;
the first angular position maps to a desired pitch response and a desired vertical translation response in the transition regime; and
the second angular position maps to a desired airspeed response and a desired longitudinal translation response in the transition regime.

14. The method of claim 2 , wherein the input mechanism comprises an inceptor, wherein the first, second, and third axes are each associated with departures of the inceptor in a fly-by-wire configuration.

Assignees

• Joby Aero Inc

Inventors

• English Blake
• Bevirt Joeben

Classifications

• B64C27/80

  for differential adjustment of blade pitch between two or more lifting rotors · CPC title

• B64C27/56

  characterised by the control initiating means, e.g. manually actuated · CPC title

• B64C13/0421

  control sticks for primary flight controls · CPC title

• B64C13/04

  actuated personally · CPC title

• B64C27/54

  Mechanisms for controlling blade adjustment or movement relative to rotor head, e.g. lag-lead movement · CPC title