Rotor position determination system with magneto-resistive sensors

Patent metadata

Field	Value
Publication number	US-9809303-B2
Application number	US-201414481074-A
Country	US
Kind code	B2
Filing date	Sep 9, 2014
Priority date	Aug 31, 2012
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

According to one embodiment, a method for determining a position of a rotor blade includes receiving a plurality of measurements from a plurality of magneto-resistive sensors and determining a position of the at least one magnet based on the received plurality of measurements. In this example, one of the plurality of magneto-resistive sensors and the at least one magnet moves with a rotor blade.

First claim

What is claimed is:

1. A rotorcraft, comprising:
a body;
a power train coupled to the body and comprising a power source and a drive shaft coupled to the power source;
a hub coupled to the drive shaft;
a rotor blade;
a grip coupling the rotor blade to the hub; and
a position determination system disposed between the blade and the body, the position determination system comprising:
at least one magnet; and
a plurality of magneto-resistive sensors proximate to the at least one magnet;
wherein the at least one magnet is movable relative to the plurality of magneto-resistive sensors as a function of movement of the grip relative to the hub.

2. The rotorcraft of claim 1 , wherein the plurality of magneto-resistive sensors comprises two or more magneto-resistive sensors, the rotorcraft further comprising:
a position determining unit in communication with the plurality of magneto-resistive sensors, the position determining unit configured to:
receive a plurality of measurements from the two or more magneto-resistive sensors;
analyze a probable accuracy of each of the received plurality of measurements;
select the measurement of the received plurality of measurements having the highest probable accuracy; and
determine a position of the at least one magnet based at least in part on the selected measurement.

3. The rotorcraft of claim 1 , wherein the position determination system is disposed between the blade and at least part of a hub, wherein a grip couples the rotor blade to the hub.

4. The rotorcraft of claim 1 , wherein the position determination system is disposed between a rotor system and a rotor mast.

5. The rotorcraft of claim 1 , further comprising a position determining unit in communication with the plurality of magneto-resistive sensors, the position determining unit configured to:
receive a plurality of measurements from the plurality of magneto-resistive sensors, the plurality of measurements representative of an orientation of a flux received at each of the plurality of magneto-resistive sensors; and
determine a position of the at least one magnet based on the received plurality of measurements.

6. The rotorcraft of claim 5 , the position determining unit further operable to determine a position of the rotor blade based on the position of the at least one magnet.

7. The rotorcraft of claim 1 , wherein the plurality of magneto-resistive sensors comprises a first plurality of magneto-resistive sensors comprising sensors substantially aligned along a first direction and a second plurality of magneto-resistive sensors comprising sensors aligned along a second direction.

8. The rotorcraft of claim 7 , wherein the second direction is different than the first direction, the rotorcraft further comprising a position determining unit in communication with the plurality of magneto-resistive sensors, the position determining unit configured to:
receive a first plurality of measurements from the first plurality of magneto-resistive sensors and a second plurality of measurements from the second plurality of magneto-resistive sensors;
determine a position of the at least one magnet in the first direction based on the received first plurality of measurements; and
determine a position of the at least one magnet in the second direction based on the received second plurality of measurements.

9. The rotorcraft of claim 7 , wherein the second direction is substantially parallel to the first direction, the rotorcraft further comprising a position determining unit in communication with the plurality of magneto-resistive sensors, the position determining unit configured to:
receive a first plurality of measurements from the first plurality of magneto-resistive sensors and a second plurality of measurements from the second plurality of magneto-resistive sensors;
analyze a probable accuracy of each of the received first and second plurality of measurements;
select the measurement of the received first and second plurality of measurements having the highest probable accuracy; and
determine a position of the at least one magnet based at least in part on the selected measurement.

10. The rotorcraft of claim 7 , wherein:
the position determination system comprises at least two magnets comprising a first magnet and a second magnet;
the first plurality of magneto-resistive sensors is proximate to the first magnet; and
the second plurality of magneto-resistive sensors is proximate to the second magnet.

11. The rotorcraft of claim 10 , the position determining unit further operable to determine a feathering position of the rotor blade based on the relative positions of the first and second magnet.

12. A method for determining a position of a rotor blade, comprising:
receiving a plurality of measurements from a plurality of magneto-resistive sensors, the plurality of magneto-resistive sensors being proximate to at least one magnet, wherein one of the plurality of magneto-resistive sensors and the at least one magnet moves with a rotor blade connected to a hub by a grip; and
determining a position of the at least one magnet based on the received plurality of measurements;
wherein the at least one magnet is movable relative to the plurality of magneto-resistive sensors as a function of movement of the grip relative to the hub.

13. The method of claim 12 , wherein the plurality of measurements are representative of an orientation of a flux received at each of the plurality of magneto-resistive sensors.

14. The method of claim 12 , further comprising determining a position of the rotor blade based on the position of the at least one magnet.

15. The method of claim 12 , wherein:
the plurality of magneto-resistive sensors comprises two or more magneto-resistive sensors; and
receiving the plurality of measurements comprises:
receive a plurality of measurements from the two or more magneto-resistive sensors;
analyze a probable accuracy of each of the received plurality of measurements;
select the measurement of the received plurality of measurements having the highest probable accuracy; and
determine a position of the at least one magnet based at least in part on the selected measurement.

16. The method of claim 12 , wherein the plurality of magneto-resistive sensors comprises a first plurality of magneto-resistive sensors substantially aligned along a first direction and a second plurality of magneto-resistive sensors aligned along a second direction.

17. The method of claim 16 , wherein:
the second direction is different than the first direction;
receiving the plurality of measurements comprises receiving a first plurality of measurements from the first plurality of magneto-resistive sensors and a second plurality of measurements from the second plurality of magneto-resistive sensors; and
determining the position of the at least one magnet comprises:
determining a position of the at least one magnet in the first direction based on the received first plurality of measurements; and
determining a position of the at least one magnet in the second direction based on the received second plurality of measurements.

18. The method of claim 16 , wherein:
the second direction is substantially parallel to the first direction;
receiving the plurality of measurements comprises receiving a first plurality of measurements from the first plurality of magneto-resistive sensors and a second plurality of measurements from the second plurality of magneto-resistive sensors; and
determining the position of the at least one magnet comprises:
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Assignees

• Bell Helicopter Textron Inc

Inventors

• Schank Troy C

Classifications

• B64C27/35

  having elastomeric joints · CPC title

• B64C27/008 Primary

  Rotors tracking or balancing devices · CPC title

• G01D5/145

  influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06) · CPC title

• G01B7/003

  for measuring position, not involving coordinate determination (coordinate measuring G01B7/004) · CPC title