Device for warning a rotorcraft pilot by means of tactile signals and making use of a trim actuator connected to a flight control member

Patent metadata

Field	Value
Publication number	US-9868513-B2
Application number	US-201514723537-A
Country	US
Kind code	B2
Filing date	May 28, 2015
Priority date	May 28, 2014
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A method of using a tactile signal warning device forming part of a human-operated flight control member of a rotorcraft. The warning device makes use of an anchorable motorized trim actuator for generating a resisting force against movement of the flight control member. The warning device comprises a warning unit that, as a function of a power margin (MP 1 ) calculated by a predictor unit in compliance with a current regulation rating of the power plant and on condition that state data indicates that an autopilot is activated in a higher operating mode, acts to generate an order to activate the trim actuator depending on the conditions under which the flight control member is being moved as identified by a force management unit.

First claim

What is claimed is:

1. A method of implementing a tactile signal warning device fitted to a human-operated flight control member of a rotorcraft, the flight control member forming part of a main control linkage for varying the pitch of blades of at least one main rotor of the rotorcraft having a drive axis that is substantially vertical and providing the rotorcraft essentially with its lift, the rotorcraft being provided with:
a power plant providing mechanical power used at least for driving rotation of the main rotor, at least one auxiliary control linkage including an autopilot for generating flight control orders controlling the use of at least one anchorable motorized trim actuator arranged in parallel with the main control linkage; and
a predictor unit that operates iteratively at a given frequency to calculate at least one power margin (MP 1 , MP 2 ) relating to the power available from the power plant by taking the difference between a predicted power (PP) and a power limit (LP 1 , LP 2 ) relating to power to be supplied by the power plant as predefined in application of a current regulation rating of the power plant,
wherein the warning device comprises a first calculation member, referred to as a “warning unit”, a second calculation member formed by the predictor unit, a third calculation member, referred to as a “force management” unit, and at least one warning member for generating a tactile sensation perceptible by the human pilot by means of the flight control member, the at least one warning member comprising at least the trim actuator opposing a resisting force against the flight control member being moved by a human, such that:
the force management unit generates command data relating to a human-originating request for lift to be supplied by the main rotor, the command data being a function of at least one item of data selected from the group comprising:
position data supplied to the force management unit by a position sensor measuring a current position of the flight control member; and
force data supplied to the force management unit by a force measurement device engaged with the main control linkage, the force data being representative of forces for moving the main control linkage under the effect of a human acting on the flight control member;
the predictor unit calculating the predicted power (PP) by summing a current power (PC) of the power plant and a variation in the power to be supplied by the power plant as requested by a human acting on the flight control member and as deduced by the predictor unit from command data that is a function of at least one of the position data and the force data; and
the warning unit collects at least one of the following items of data selected from the group comprising:
the command data as a function of at least one of the position data supplied by the position sensor and the force data supplied by the force measurement device;
at least a first said power margin (MP 1 ) supplied by the predictor unit by taking the difference between the predicted power (PP) and a first said power limit (LP 1 ); and
state data relating to activation of at least any higher operating mode of the autopilot causing the main control linkage to be used to guide the rotorcraft along at least one travel axis including at least the gravity axis;
wherein the warning unit generates an anchoring command for anchoring the trim actuator on the main control linkage, the anchoring command being generated on condition both of said first power margin (MP 1 ) and of said command data that is a function of position data and/or of force data relating to a request to increase the lift to be supplied by the main rotor;
wherein, as a result of the warning unit generating the command for anchoring the trim actuator, the predictor unit regulates activation of the motor of the trim actuator and consequently activates an anchoring command of the trim actuator on the main control linkage so as to vary the resisting force opposed by the trim actuator against human action on the flight control member; and
wherein the warning unit ceases to generate the command for anchoring the trim actuator when the force management unit generates command data representative of a human request to reduce the lift to be supplied by the main rotor, the human exerting a drive force on the flight control member that opposes a resisting force of the trim actuator.

2. A method according to claim 1 , wherein:
the method further comprises an operation of the warning unit comparing the value of the first margin (MP 1 ) and a first power threshold (SP 1 ) defined in compliance with the current regulation rating; and
the warning unit ceases to generate the command for anchoring the trim actuator when the following conditions are satisfied:
the force management unit generates command data relating to position data identifying that the flight control member is not being operated by a human; and
the warning unit identifies a value for the first power margin (MP 1 ) that is greater than or equal to the first power threshold (SP 1 ).

3. A method according to claim 1 , wherein the predictor unit regulates the activation of the motor of the trim actuator as a function of variation in the value equally well of the position data and/or of the force data.

4. A method according to claim 1 , wherein the predictor unit regulates the activation of the motor of the trim actuator as a function of variation in the first power margin (MP 1 ).

5. A method according to claim 1 , wherein as a result of the warning unit generating the anchoring command, anchoring data relating to the current anchoring position of the trim actuator on the main control linkage is supplied by the warning unit at least to the autopilot.

6. A method according to claim 1 , wherein the at least one warning member comprises a shaker installed on the flight control member, the warning unit also collects a second said power margin (MP 2 ) supplied by the predictor unit by taking the difference between said predicted power (PP) and a second said power limit (LP 2 );
the warning unit generates a command to activate the shaker under the combined conditions of the warning unit collecting both the second power margin (MP 2 ) and equally well position data and/or force data relating to a request to increase the lift to be supplied to the main rotor, and
generation by the warning unit of the command for activating the shaker is interrupted as a result of the warning unit identifying a value for the second power margin (MP 2 ) that is greater than a second predefined power threshold (SP 2 ) in compliance with the current regulation rating.

7. A method according to claim 1 , wherein the command for anchoring the trim actuator is conditional on taking account of the intrinsic resistance of the main control linkage against being moved, by the warning unit comparing the first power margin (MP 1 ) and a third predefined power threshold (SP 3 ).

8. A method according to claim 6 , wherein the command for activating the shaker issued by the warning unit is also conditional on taking account of the intrinsic resistance of the main control linkage against being moved, by the warning unit comparing the second power margin (MP 2 ) and a fourth predefined power threshold (SP 4 ).

9. A method according to claim 1 , wherein the command data causing anchoring of the trim actuator to be interrupted is deduced from combined conditions comprising firstly force data less than or equal to a predefined force threshold (SE) and secondly position data identifying that the flight control member is being moved by a human.

10. A method according to claim 6 , wherein the shaking generated by the shaker vari

Assignees

• Airbus Helicopters

Inventors

• Sandri Florence

Classifications

• B64C13/507 Primary

  with artificial feel · CPC title

• B64C13/345

  with artificial feel · CPC title

• B64C13/0427

  for actuating trim · CPC title

• B64C13/18

  using automatic pilot · CPC title

• G08B6/00

  Tactile signalling systems, e.g. tactile personal calling systems · CPC title