Virtual Macro Site Analysis using Wireless Sensor Networks

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Università degli Studi di FirenzeDipartimento di Elettronica e Telecomunicazioni

Virtual Macro Site Analysis using

Wireless Sensor Networks

Davide Di Palma, Francesco Chiti, Gianfranco Manes, Luca Bencini, Giovanni Collodi, Romano Fantacci, Antonio Manes

MIDRA Consortium

WISES08 Sixth Workshop on Intelligent Solutions in Embedded Systems University of Applied Sciences Regensburg, Germany, July 10/11th, 2008

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Outline

• The old approach to WSN design: let’s start from protocols

• The new approach: application oriented WSN.

• The GoodFood project and the agro-food monitoring

• The “ad-hoc” designed WSN system

• Pre-industrial pilot sites

• New commercial pilot sites

• The macro site analysis approach

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The old approach to WSN design: let’s start from protocols

Year: 2004

The prevalent and common opinion was finding an infrastructureprotocol, as the best trade off satisfying the widest set of

different application requirements

A wide literature of MAC protocol solutions

Many routing algorithms

Too few “long life” and “reliable” experimental test beds

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The new approach: application oriented WSN.

Year: 2008

If we want to bring WSN out of the labsinto open fields, WSN must be studied, designed and developed

following the “application oriented approach”.

Dividing different applications into “requirement-homogeneous groups

Designing protocols (and hardware if necessary!) to fulfil only one group’s

requirements

Create an end-to-end system, from the sensor to the end-user

As a result: a real long life, high reliable pilot site can be deployed

How ?

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The GoodFood project and the agro-food monitoring

Application: Vineyard Monitoring

Slow physical parameters variations.

Wide areas to cover

Unmanned and stand-alone operations

At least one farming season without battery change

Hostile environment

10 countries

FP6-IST-1-508774 GoodFood • Objective: to demonstrate to the agro-food sector actors the advantages driven to the complete food chain control by the use of Micro and Nano - technology inspired systems

• SubTask: to introduce Ambient Intelligence (AmI) paradigms in Agriculture using WSN technology and to implement a demonstrator for the wine chain

Application Specifications

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The “ad-hoc” designed WSN system

Courtesy of HTA

“ad-hoc” MAC Protocol: STAR MAC “ad-hoc” Dynamic Multihop Protocol

Target Next hop

Hop counter

Phase Link quality

Battery level

Congestion level

X NX ϕ X η X BX CX Sink

Y NY ϕ Y η Y BY CY

“ad-hoc” Hardware Platform: MIDRA Mote

0 25 50 75 [m]

0 25 50 75 100 125 150 175 200 [m]

0 25 50 75 100 125 150 175 [m]

0 25 50 75 [m]

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• Stand-alone communication platform,

providing transparent bi-directional

wireless TCP/IP connectivity for remote

monitoring.

• Powered by solar panels.

• Improved robustness.

• Reconnection with dynamic IP address

assignment.

The “ad-hoc” designed WSN system

“ad-hoc” Gateway Unit “ad-hoc” End-User Interface

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The “End-To-End System”

GPRS Link

Server

World Wide Web

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System Details:

• 1 GPRS Gateway Station• 12 Wireless Sensor Network Nodes• 30 Distributed Sensors• 4 Fully Monitored Plants

The First Pilot site was installed on 2005 in one hectare of Vineyard on a mild Chianti hill at San Casciano.

Pre-industrial pilot sites

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Pre-industrial pilot sites

Pech RougeSelvapiana

Castello di Ama

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2,5 years of running at Montepaldi 198 Sensors deployed 8 Hectares of vineyard monitored 4 GPRS Gateway (operating in different countries) Multihop and power saving strategies adopted 11 months of guaranteed battery life

Some Figures

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New commercial pilot sites

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Downey Mildew Risk:Apply Treatments

Water Deficit:Irrigate.Powdery Mildew Risk:

Apply Treatments

The macro site analysis approach

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Conclusions

An End-To-End System

2,5 millions of data gathered

Application Driven Approach to WSN: Results

Site-specific Management

Enhanced environment knowledge

Real time collaboration of different experts on macro-areas

Macro-Site knowledge using detailed analysis of micro areas

…

It’s just the beginning!

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Acknowledgments

The authors gratefully acknowledge many contributions by their colleagues in the GoodFood project, in particular the Groups of :

-Scuola Superiore Sant’Anna Italy-Synapsis Italy -HTA Switzerland-Tyndall Ireland -EADS Germany

The support from the European Commission is gratefully acknowledged.

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…thanks for your attention!

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ID PhaseHop

counterSequence Number

MAC PDU header

STAR MACSynchronous Transmission Asynchronous Reception

1. Completely novel approach effectively joining:

• WISE MAC (phase based transmission scheduling)

• S-MAC (duty cycle)

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• Applied algorithms:

• Static 1 reference next hop to the gateway is a priori defined for each node

• Partial Dynamic additional back up neighbors facing faults (turning off) or congestion are a priori defined for each node

• Full Dynamic number and reliability of the next hop is dynamically updated depending on the network status changing

• Routing table for an ordinary node

Static routing algorithm

Partial dynamic routing algorithm

Target Next hop

Hop counter

Phase Link quality

Battery level

Congestion level

X NX ϕX ηX BX CX Sink

Y NY ϕY ηY BY CY

Multihop Routing

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Current Consumption in RX (Listen)

~ 12 mA

Current Consumption in Power Saving (Sleep)

~ 0.01 mA

Current Consumption in TX ~ 30 mA

Number of cycles per hour 4

Battery Capacity 7 Ah

Battery life 11 mesi

Max Radio Coverage 200 m

0 25 50 75 [m]

0 25 50 75 100 125 150 175 200 [m]

0 25 50 75 100 125 150 175 [m]

0 25 50 75 [m] Courtesy of HTA

STAR MAC Implementation