Wheel Accelerometer Monitoring for Landing Gear Axle Deflection

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Solution Overview

Problem

Existing aircraft landing gear monitoring systems lack real-time deflection detection capabilities, requiring additional equipment and maintenance, and plastic deformations are only detectable during heavy maintenance operations.

Innovation Solution

Utilize the signals from accelerometers integrated into tire pressure monitoring systems (TPMS) on landing gear wheels to estimate deflection angles of the axles in real-time without additional hardware, by processing accelerometer data to filter and estimate deflection angles using low-pass filters and pseudo-inverse methods.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If additional hard landing detectors are equipped on the landing gear, then the ability to detect rough landings and deformations is improved, but the device complexity and maintenance requirements increase

Engineering Contradiction:
Improvedeflection detection capabilityVSAvoidequipment complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The accelerometer originally designed for tire pressure monitoring is made multi-functional by also using it to detect landing gear deflections and hard landings. This allows a single device to serve both tire monitoring and structural health monitoring purposes, eliminating the need for separate detection systems.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The existing TPMS accelerometer serves itself by providing dual functionality. The same sensor that monitors tire pressure also detects axle deflections and landing impacts, making the system self-sufficient and reducing the need for additional dedicated sensors.

Inventive Principle:
Principle #25Self-service

2Reliability

If hard landing detectors are installed on the landing gear, then the detection of plastic deformations is improved, but the weight of the landing gear increases

Engineering Contradiction:
Improvedeformation detection reliabilityVSAvoidlanding gear weight
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The TPMS accelerometer is utilized for dual purposes: tire pressure monitoring and structural deformation detection. This multi-functional approach provides reliable deformation detection without adding the weight of dedicated hard landing detectors.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The existing accelerometer in the TPMS system serves additional functions by detecting landing gear deflections and hard landings, eliminating the need for separate detection equipment and associated weight.

Inventive Principle:
Principle #25Self-service

3Productivity

If traditional monitoring methods are used, then the landing gear can be monitored, but real-time deflection monitoring is not available and plastic deformations are only detectable during heavy maintenance

Engineering Contradiction:
Improvemaintenance efficiencyVSAvoidreal-time deflection information
Core Design Contradiction:
ProductivityVSLoss of information

Solution Approach 1:

The system performs preliminary detection of potential issues during normal operations. By continuously monitoring deflections in real-time, the system can identify problems before they become critical, allowing for proactive maintenance scheduling rather than waiting for heavy maintenance events.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system provides continuous feedback on landing gear deflection status during normal operations. This real-time information flow enables operators to monitor the health of the landing gear and schedule maintenance based on actual conditions rather than fixed intervals.

Inventive Principle:
Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enables real-time monitoring of landing gear deflections, detecting plastic deformations during normal operations, reducing the need for additional equipment and facilitating timely maintenance.

Implementation Method 1

at least one accelerometer secured to a wheel of the landing gear mounted for rotation on an axle of the landing gear

Methodology Applied
Scientific EffectAccelerometer: Accelerometer

Data Source

PatentEP4341106B1Method for monitoring an aircraft landing gear employing at least one accelerometer supported by a wheel of the landing gear, and aircraft implementing this method
Publication Date: 2025.07.02 SAFRAN LANDING SYSTEMS
  • EP4341106B1 patent drawingFigure 1
  • EP4341106B1 patent drawingFigure 2
  • EP4341106B1 patent drawingFigure 3~4

AI summary

Method for monitoring an aircraft landing gear (100) comprising the step of using information from at least one accelerometer (108) firmly secured to a landing gear wheel (103) mounted to rotate on a landing gear axle (102) to estimate an angle of deflection of the axle at least when the wheel is in contact with the ground. Aircraft implementing this method.