DEVICE AND PROCESS FOR DETERMINING A RUNWAY STATE, AIRCRAFT INCLUDING SUCH A DEVICE AND PILOTING ASSISTANCE SYSTEM USING SAID RUNWAY STATE

• US 20140012437A1
• Filed: 07/31/2012
• Published: 01/09/2014
• Est. Priority Date: 08/01/2011
• Status: Active Grant

• Current Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV)
• Original Assignee: Airbus Operations (European Aeronautic Defence and Space Company EADS NV)
• Inventors: Jones, Logan
• Granted Patent: US 9,299,261 B2
• Time in Patent Office: Days
• US Class Current: 701/15
• CPC Class Codes: B60T 2210/12 Friction
• CPC Class Codes: B60T 2210/13 Aquaplaning, hydroplaning
• CPC Class Codes: B60T 8/1703 for aircrafts
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B64C 25/42 Arrangement or adaptation of brakes
• CPC Class Codes: G08G 5/0013 with a ground station
• CPC Class Codes: G08G 5/0021 located in the aircraft
• CPC Class Codes: G08G 5/0086 for monitoring terrain radar or analogous systems specially adapted for terrain avoidance G01S13/935
• CPC Class Codes: G08G 5/06 for control when on the ground
• CPC Class Codes: G08G 5/065 Navigation or guidance aids, e.g. for taxiing or rolling

Abstract

This invention relates to a device and process for determining an airport runway state (12), as well as for using such data. The process includes: acquisition (A1) of measurement data pertaining to at least one physical size of an aircraft (10), during the take off or landing roll phase of the aircraft on said runway; obtaining (A2), using the data acquired, a plurality of estimated adhesion values “μ” of the runway, corresponding to a respective plurality of taxiing moments of the aircraft; obtaining (A3), using the data acquired, a slip ratio value “s” of at least one of the aircraft'"'"'s wheels for each said taxiing moment, so as to obtain (A4) a plurality of coupled data points [s,μ]; and determination of a runway state by comparing (A5.2) the coupled data points [s,μ] profile with at least one predetermined profile.

Claims

1. A process for determining the state of a runway including the following steps:

acquiring measurement data relating to at least one physical size of an aircraft, during an aircraft take off or landing roll phase on said runway;

obtaining, using the acquired data, a plurality of estimated adhesion values “

μ

”

of the runway, corresponding to a plurality of respective moments of aircraft roll;

obtaining, using the acquired data, a slip ratio value “

s”

of at least one aircraft wheel for each said moment of aircraft roll, so as to obtain several coupled data points;

determining a runway state by comparing the coupled data points profile with at least one predetermined profile.

2. Process as set forth in claim 1, wherein determining a runway state by comparison includes selecting, from among a set of predetermined profiles each associated with a different runway state, the predetermined profile that most resembles the profile of the coupled data points.

3. Process as set forth in claim 1, wherein determining a runway state by comparison includes obtaining a plurality of slope values “

k”

of the coupled data points profile for a plurality of adhesion μ

values, so as to obtain a plurality of coupled data points; and

determining, from among a set of zones predetermined in space each associated with a different runway state, an appurtenance zone of a majority of said coupled data points.

4. Process as set forth in claim 3, wherein at least one mechanical stiffness pertaining related to the tire of the aircraft wheel is calculated using measurement data acquired during the aircraft roll phase, and the predetermined zones are defined using the at least one predetermined profile, which varies according to the calculated mechanical stiffness value.

5. Process as set forth in claim 1, wherein the predetermined profile is a parametric profile, and determination of a runway state by comparison includes the adjusting of the parametric profile to said coupled data points and the determination of a runway state from at least one characteristic value of the adjusted profile.

6. Process as set forth in claim 1, wherein said predetermined profile is in the form f(s, μ

_k, μ

_s, a, F_z, c_p) where, at the corresponding taxiing moments, μ

_k is a dynamic adhesion coefficient, μ

_s is a static adhesion coefficient, a represents the contact area between the tire of the aircraft'"'"'s wheel and the runway, F_z is a vertical load applied to the axis of the wheel and c_p is a mechanical stiffness value pertaining to the tire of the wheel.

7. Process as set forth in claim 1, wherein a slip ratio value “

s”

of one of the aircraft'"'"'s wheels for one moment of taxiing is obtained by calculating the following ratio;

8. Process at set forth in claim 1, wherein said determination of a runway state by comparison is repeated over several sets of coupled data points, where the sets correspond to distinct taxiing phases.

9. Process as set forth in claim 8, wherein different determined runway states are associated with different portions of the runway corresponding to the respective taxiing phases.

10. Device for determining the state of a landing runway, including:

a module for acquiring measurement data pertaining to at least one physical size of an aircraft, during a taxiing phase of the aircraft on said runway;

a calculator to obtain, using the acquired data, a slip ratio value “

s”

of at least one of the aircraft'"'"'s wheels for each said taxiing moment, so as to obtain a plurality of coupled data points;

a module for determining the state of a runway by comparing the profile of the coupled data points to at least one predetermined profile.

11. Device as set forth in claim 10, wherein the determination module is configured to select, from among a set of predetermined profiles each associated with a different runway state, the predetermined profile that most resembles the profiles of the coupled data points.

12. Device as set forth in claim 10, wherein the determination module is configured to obtain a plurality of slope values “

k”

of the coupled data points profile for a plurality of adhesion μ

values, so as to obtain a plurality of coupled data points; and

to determine, from among a set of zones predetermined in space each associated with a different runway state, a zone of appurtenance of a majority of said coupled data points.

13. Device as set forth in claim 10, wherein the predetermined profile is a parametric profile, and the determination module is configured to adjust the parametric profile to said coupled data points and to determine the runway state from at least one characteristic value of the adjusted profile.

14. Aircraft including at least one device for determining a runway state as set forth in claim 10.

15. Aircraft piloting assistance system, in particular for landing said aircraft, including at least one device as set forth in claim 10 on board at least one aircraft, and one ground station able to receive an information item about the runway state determined by said device and able to transmit said information about the runway state to at least one other aircraft in the approach phase.