Magnetostrictive Optical Sensor Array for Position Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing proximity sensors face interference from metallic objects and electromagnetic interference, and misalignment issues lead to erroneous distance measurements between objects, requiring recalibration and access to the target or sensor.

Innovation Solution

A system comprising a two- or three-dimensional array of magnetostrictive optical sensors arranged to produce signals indicative of proximity to magnetic elements, allowing for accurate determination of object position using bilateration and trilateration methods, resistant to offsets in the x-y plane and eliminating the need for recalibration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single proximity sensor is used to measure distance between objects, then the measurement is simple, but misalignment of the sensor or target leads to erroneous distance determination

Engineering Contradiction:
Improvesensor systemVSAvoiddistance measurement
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent divides a single sensor into multiple sensors (at least two sensors in each dimension, forming a two-dimensional or three-dimensional array). This segmentation allows the system to measure proximity from multiple locations simultaneously, enabling accurate position determination through bilateration or trilateration methods, and making the measurement resistant to misalignment of individual sensors.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from a single-point measurement to multi-dimensional measurement by arranging sensors in a two-dimensional or three-dimensional array. This dimensional expansion enables the system to determine position in multiple dimensions and eliminates the need for precise alignment in a single direction, as the array can accommodate misalignment through geometric calculation.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If misalignment occurs in the sensor-target system, then recalibration is required, but recalibration requires access to the target or sensor which may be inaccessible

Engineering Contradiction:
Improvemeasurement accuracyVSAvoidrecalibration process
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent performs preliminary action by using multiple sensors to establish geometric relationships and calculate position through bilateration or trilateration before misalignment issues arise. The system is designed to be inherently resistant to misalignment from the outset, eliminating the need for subsequent recalibration operations.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent enables the system to self-correct for misalignment through geometric calculation. The multiple sensors automatically compensate for positional offsets by using the relative positions and proximity measurements from each sensor in the array to determine the true position of the target, making the system self-adjusting without external intervention.

Inventive Principle:
Principle #25Self-service

3Measurement precision

If induction proximity sensors are used, then metallic targets can be detected, but interference from other metallic objects and electromagnetic interference occurs

Engineering Contradiction:
Improvetarget detectionVSAvoidelectromagnetic interference
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent introduces an intermediary element - a magnetic element attached to the target - that mediates between the sensors and the target. The magnetostrictive optical sensors detect the position of this magnetic intermediary rather than directly detecting the target, which eliminates interference from other metallic objects and electromagnetic interference while maintaining accurate target detection capability.

Inventive Principle:
Principle #24Intermediary (Mediator)

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

The system provides accurate and reliable determination of object position and distance, resistant to misalignment and interference, without the need for recalibration, ensuring precise monitoring and simplifying installation procedures.

Implementation Method 1

Another known proximity sensors is based on the principle of magnetostriction, where the shape or dimension of a magnetostrictive material varies when subjected to varying magnetic field strength

Methodology Applied
Scientific EffectMagnetostriction: Magnetostriction

Implementation Method 2

the optical element of at least one of the sensors is a Fibre Bragg Grating (FBG)

Methodology Applied
Scientific EffectFibre Bragg Grating:

Implementation Method 3

the optical element of at least one of the sensors is a Fibre Fabry-Perot (FFP) interferometer

Methodology Applied
Scientific EffectFibre Fabry-Perot interferometer: Fabry-Perot Interferometer

Data Source

PatentEP3139134B1Position sensing
Publication Date: 2020.03.18 AIRBUS OPERATIONS LTD
  • EP3139134B1 patent drawingFigure 1~2
  • EP3139134B1 patent drawingFigure 3~4
  • EP3139134B1 patent drawingFigure 5~6

AI summary

Disclosed is an apparatus (102) for determining the position of an object (108) having one or more magnetic elements (104). The apparatus (102) comprises a plurality of magnetostrictive optical sensors (11, 12, 21, 22), each arranged to produce a signal which is indicative of a proximity of the sensor (11, 12, 21, 22) to the one or more magnetic elements (104). The apparatus (102) is arranged to determine the position of the object (108) based on a plurality of such proximity signals.