Method for controlling at least one aerodynamic stabilizer member of a hybrid helicopter, and a hybrid helicopter

Patent metadata

Field	Value
Publication number	US-11634209-B2
Application number	US-202117198329-A
Country	US
Kind code	B2
Filing date	Mar 11, 2021
Priority date	Mar 12, 2020
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A method for optimizing the operation of at least one first propeller and of at least one second propeller of a hybrid helicopter. The method comprises the following step during a control phase: deflection, with an autopilot system, of at least one aerodynamic stabilizer member into a setpoint position having, with respect to a reference position, a target deflection angle that is a function of a setpoint deflection angle, the setpoint deflection angle being calculated by the autopilot system in order to compensate for a torque exerted by the lift rotor at zero sideslip.

First claim

What is claimed is:

1. A method for optimizing the operation of at least one first propeller and of at least one second propeller, which are arranged transversely on either side of an airframe of a hybrid helicopter, the hybrid helicopter including a lift rotor arranged above the airframe, the hybrid helicopter including at least one aerodynamic stabilizer member exerting a transverse lift, the aerodynamic stabilizer member being able to rotate relative to a support of the hybrid helicopter, the method comprising the following step during a control phase: deflection, with an autopilot system, of the aerodynamic stabilizer member into a setpoint position having, with respect to a reference position, a target deflection angle,
wherein the target deflection angle is equal to a setpoint deflection angle at least when this setpoint deflection angle is within a range delimited by an included predetermined minimum angle and an included predetermined maximum angle, the setpoint deflection angle being calculated by the autopilot system in order to compensate for a torque exerted by the lift rotor at zero sideslip.

2. The method according to claim 1 ,
wherein the method comprises the following step: calculation of the setpoint deflection angle, with the autopilot system, as a function at least of a forward speed of the hybrid helicopter, of a torque exerted by the lift rotor on the airframe, and of a volumic mass of the air surrounding the hybrid helicopter.

3. The method according to claim 1 ,
wherein the method comprises a step of calculating the setpoint deflection angle, with the autopilot system, by means of the following relation:
delta V =( C /(0.5* ro*v 2 )− N 1)/( N 2),

where “deltaV” represents the setpoint deflection angle ANGCONS, “C” represents a torque exerted by the lift rotor on the airframe, “V 2 ” represents a forward speed of the hybrid helicopter, squared, “ro” represents a volumic mass of the air, “0.5*ro*v 2 ” represents a dynamic pressure, “N1” represents a first coefficient which is a function of an aerodynamic yaw moment of the hybrid helicopter at zero sideslip and when the aerodynamic stabilizer member is in the reference position, reduced by the dynamic pressure, “N2” represents a second coefficient equal to a constant, “/” represents the division sign, “−” represents the subtraction sign, “*” represents the multiplication sign, “=” represents the equals sign.

4. The method according to claim 3 ,
wherein the first coefficient is equal to the aerodynamic yaw moment of the hybrid helicopter, reduced by the dynamic pressure, at zero sideslip and when the aerodynamic stabilizer member is in the reference position.

5. The method according to claim 3 ,
wherein the first coefficient is equal to the aerodynamic yaw moment of the hybrid helicopter, reduced by the dynamic pressure and corrected by an integral corrector, at zero sideslip and when the aerodynamic stabilizer member is in the reference position; the corrector being a function of a gain as well as of a subtraction either of a first pitch of first blades of the first propeller minus a second pitch of second blades of the second propeller, or of a first thrust exerted by the first propeller minus a second thrust exerted by the second propeller, or of a first torque exerted by the first propeller, minus a second torque exerted by the second propeller.

6. The method according to claim 5 ,
wherein the first coefficient is determined by the following relation:
N 1=( N 0/ q )+ k *int( diff ),

where “N1” represents the first coefficient, “N0/q” represents the aerodynamic yaw moment NO of the hybrid helicopter, reduced by the dynamic pressure q, at zero sideslip and when the aerodynamic stabilizer member is in the reference position, “diff” represents the subtraction, “k” represents a predetermined gain, “−” represents the subtraction sign, “+” represents the addition sign, “*” represents the multiplication sign, “=” represents the equals sign, “k*int(diff)” represents the integral corrector equal to a product of the predetermined gain and an integral with respect to the time of the subtraction.

7. The method according to claim 5 ,
wherein the gain varies as a function of a forward speed of the hybrid helicopter.

8. The method according to claim 5 ,
wherein the corrector is frozen when the hybrid helicopter is in a dynamic piloting phase.

9. The method according to claim 8 ,
wherein the method comprises a step of detecting a dynamic piloting phase if at least one of the following conditions is satisfied:
maneuvering of a yaw control configured to modify a differential pitch component of the first pitch of the first blades of the first propeller and of the second pitch of the second blades of the second propeller;
an absolute value of a load factor in a transverse direction in a reference frame of the hybrid helicopter is greater than a load factor threshold; and
an absolute value of a roll angle of the hybrid helicopter is greater than a roll threshold.

10. The method according to claim 5 ,
wherein the corrector is frozen when an absolute value of a difference is less than a freeze threshold, the difference being equal:
to the first pitch of the first blades of the first propeller minus the second pitch of the second blades of the second propeller;
or to the first thrust exerted by the first propeller minus the second thrust exerted by the second propeller; and
or to the first torque exerted by the first propeller minus the second torque exerted by the second propeller.

11. The method according to claim 1 ,
wherein the control phase is implemented when the hybrid helicopter is carrying out a cruising flight phase.

12. The method according to claim 1 ,
wherein the deflection of the aerodynamic stabilizer member into a setpoint position, with the autopilot system, is achieved by applying an open control loop.

13. A hybrid helicopter provided with at least one first propeller and with at least one second propeller which are arranged transversely on either side of an airframe of this hybrid helicopter, the hybrid helicopter including a lift rotor arranged above the airframe, the hybrid helicopter including at least one aerodynamic stabilizer member exerting a transverse lift, the aerodynamic stabilizer member(s) being able to rotate relative to a support of the hybrid helicopter,
wherein the hybrid helicopter comprises an autopilot system configured to apply the method according to claim 1 , the autopilot system comprising a flight control computer configured to apply the method according to claim 1 , the autopilot system comprising at least one actuator connected to the aerodynamic stabilizer member and to the flight control computer.

14. The hybrid helicopter according to claim 13 ,
wherein the autopilot system comprises at least one instance of at least one of the following components, connected to the flight control computer: a speed sensor, a torque sensor configured to measure information relating to a torque exerted by the lift rotor, a first sensor for detecting the first pitch of first blades of the first propeller, a second sensor for detecting the second pitch of second blades of the second propeller, a maneuvering sensor for determining whether a pilot is maneuvering a yaw control, a sensor for measuring a load factor in a transverse direction in a reference frame of the hybrid helicopter, an angular roll sensor measuring a roll angle of the hybrid helicopter, first and second torque sensors for detecting the torque respectively of the first propeller and of the second propeller, a first thrust sensor for evaluating a first thr

Assignees

• Airbus Helicopters
• Airbus helicopter

Inventors

• Eglin Paul
• Huot Remy
• Conroy Antoine

Classifications

• G05D1/495

  to ensure stability · CPC title

• G05D2105/22

  of humans · CPC title

• G05D2109/24

  Convertible aircraft, e.g. tiltrotor aircraft · CPC title

• B64C5/10

  adjustable · CPC title

• B64C27/82

  characterised by the provision of an auxiliary rotor or fluid-jet device for counter-balancing lifting rotor torque or changing direction of rotorcraft · CPC title