NEWTON - Novel Sensing Network for

Intelligent Monitoring 09/07/2013

Dr. Dave Graham

Mr. Jeff Neasham

Dr. Zhiguo Ding

Prof. Gui Yun Tian

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NEWTON Objectives1. 4 year project - Bridging the gap between NDE

and SHM, using a novel combination of passive wireless technology with PEC and acoustic wave sensing (Newcastle University).

2. Applying non-linear system identification and model-based signal processing to assess the location, size, and microstructure of defects in structures (University of Sheffield).

3. Building cloud-based diagnostic software architectures, and data management for the software implementation of developed technologies (University of York).

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System Overview

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Sensor Features

SHM Sensor

Permanent Install

Passive

Low Power

Wireless Power Delivery

Multiple Sensing Modalities

Bulk Acoustic Wave

Surface Acoustic Wave

Pulsed Eddy Current etc.

Large Read Range

Robust Backscatter Communications

Error Checking

Optimal Antenna

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Reader

Application Example

S1S2

Dat

a

Pow

er

Data Management

(York)

Feature Extraction(Sheffield)

10m+range

• Valuable infrastructure.• Sensors at critical locations.• Completely passive sensors.• Very large read range!• Efficient, cost effective

measurements.

Wifi, GPRS, SD card

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Proposed Design

Packet StructureReader (Front End)

High frequency (868MHz) Power and Communications

Tag

Sensing

Low Power Microcontroller Comms /

Power Antenna

Power Harvesting

Reader Antenna

Power Supply

RF Signal Source

Processing / Demodulation

Error Checking

Waveform Generation

ADC

Modulation

MUT

Digital Interface (SPI)ID (4Bytes) Data (<20Bytes)

Drive Circuit

Temperature Sensor

MUT

Tag

Reader

Data Management

10m+

?

Data Management

(York)

Feature Extraction (Sheffield)

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Sensing Modes

SHM Sensor

Acoustic

Bulk Wave

Guided Wave

Surface Acoustic Wave

Electromagnetic / Magnetic

Pulsed Eddy Current

Giant Magneto-Resistance

Flux Leakage

Hybrid

EMAT

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• Scope / Sensitivity Trade-off• Resolution• Ultra-low Power Operation• Minimise Complexity / Cost• Size / Profile• ADC Specification• Installation

Sensing Challenges

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Design Flow

Range >10m Power BudgetImplement

Sensing Payload Prototype

Evaluate Performance

Feature Analysis (University of

Sheffield)

Is Technique Viable?

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• Power Budget < 20uJ per measurement• Read range <25m• Temperature sensing for drift compensation • 32-bit ID for position information• 16 bit CRC for error checking• Transmission @ 38.4k baud• 2MHz sampling with today’s hardware• Both EM and acoustic techniques are viable

within these constraints

What is Achievable?

0 1 2 3 4 5 6 7 8 90

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Time (s)

AD

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0mm defect2mm defect4mm defect6mm defect8mm defect10mm defect12mm defect14mm defect16mm defect

0 1 2 3 4 5 6 7 8 9-5

0

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Time (s)

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2mm defect4mm defect6mm defect8mm defect10mm defect12mm defect14mm defect16mm defect

-5 0 5 10 15 20-20

-10

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AD

C R

ead

ing

Time (s)

-5 0 5 10 15 20-2

-1

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rb)

Time (s)

-5 0 5 10 15 200

0.5

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plitu

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Time (s)

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ConclusionNEWTON Project• Proposed sensors have a lot to offer SHM in

industry. • Potential for long range, wireless measurement• Completely passive, very long lifetime• Combine acoustic measurements and EM

measurements for better structure coverage• Challenge is achieving high sensitivity, high

resolution within the power, size and cost constraints