Interactive textiles today

Prof. Lieva Van Langenhove

Department of Textiles

Smart and electronic textiles?

Smart textile measures/reactsReaction is intrinsicReaction is controlled by electronicsActive data processing

Functions of smart textiles

• Sensor• Actuator • Data processing• Communication• Energy

Why textiles?

• All around• Versatile• Light weight• Large contact area with body• Comfortable• Easy to use

Effects from nano to macro

Objective

The textile can absorb, reflect, shield, measure or generate …

TemperatureHeat fluxElectromagnetic fieldsHumidityChemicalsGasesRadiation

Electric propertiesMovementForcesMechanical strengthOdourAcousticBiological

Electromagnetic fields: conductivetextiles

Stainlesssteel

Kevlarcoatedwith

Knitted Woven non woven

polypyrrol copper gold

Conductive textiles as sensor

Textrodes Respibelt

EMG monitoring

Myography for stress measurementContactless

Professional use

EMG sensorsembroidered

laminated

(www.context-project.org)

Electrotherapy

• Homogeneous currentdensity

• Electrode design• Current supply

• Contact with skin• Conditions of current

• Tactile stimulus• Skin stimulation

• Tissue reinforcement• Sensory effects

• Muscle stimulation• Warming up• Exercising

•Drug delivery• Skin permeability• Iontophoresis

Current density must be homogeneous

Peak current density: 33 mA/mm2

Uniform profile

Stripeprofile

Concentricsquare

21 mA/mm² 15.6 mA/mm2

Electrotherapy prototypes

Heating

Polar Sefar

Cooling

• Grado Zero F1 pilots• Prospie project:

• Salts that cool when wetted• Ventilation in clothing• Phase change materials

www.prospie.eu

Self adapting insulation/ventilation

Biomimetics: based on pine coneCoating reacting onhumidity

G. JenonimidisUniversity of reading UK

Phase change materials

•Developed by NASA in 90’s•Cope with large temperature variations•More than 500 substances•Uses melting heat: about 200 times higher thancaloric value•Paraffin waxes in micro capsules

Thermoregulation challenges

• Sensors • Determining thermal comfort• Adequate control strategies• Actuators:

• Cooling• Insulation• Ventilation

Mechanical actuators

Mechanisms

Thermal/hygral expansionShape memory materialsGel based systemsElectro active polymersElectrostrictive systems

Status

Limited flexibilityOne way, expensive, controlBased on diffusion: slowSlow, low voltageFast, high voltage

Shape memory alloys: Nitinol

Goes to a predifinedshape above transitiontemperature

Grado ZeroSelf ironing shirt

Smart interface: active dyes

skin pH

days

Skin pH-variation after burn wound

L. Van der Schueren, K. De Clerck

Textile display

France Telecom

Built in LED

Lumalive

OLED

Textile structureOrganic materialsImage qualityYieldOxidation

TITV

Biochemical actuators

Micro capsules Active gels Cyclodextrins

Communication

Within componentsBetween components in a suit‣ Conductive fibres‣ Optical fibres

With the wearer: • keyboard, • display

Wide environment: • inductive, • antenna

Energy

Optimise consumption and distributionBalance between storage and “generation”Storage:

• Flexible chemical batteries• Capacity based fibre batteries

Generation from:• Heat• Motion• Light

Energy from heat: Seebeck

Uses:•P semiconductor•N semiconductor•Conductive materials

Infineon demonstrator

Areas of cooling

Areas of heating

Energy from motion: piezo electrics

Deformation leads to E fieldNeeds large surface, nothicknessPVDFChallenges:•Materials•Concepts•Production (poling)Electrode

Piezo electric layerElectrode

Photovoltaics

Organic photovoltaicsNanostructuresDyestuffsChallenges:•Materials•Production•Stability•Concept

Transparent layer/ Electrode

N semiconductor

P semiconductor

Electrode

+ -+ -

+ -

STELLA: Stretchable Electronicswww.stella-project.eu

Creating the paths: Sefar

Inner garment

Outer garment

Accelerometers

GPSAntenna

TextileAntenna

Flexible Battery

ExternalTemperature

Alarm

DataRecording

Processing Transmission

Victim patch

Parameter

•Heart beat rate

•Respiratory rate

•Body Temperature

Cfr. inner garment

Monitoring Centre

GPS

Position ProeTEX PDA Google Earth

145.202740 45.202624 45.202755

09.133803 09.133932 09.133844

245.203345 45.203210 45.203322

09.134353 09.134457 09.137197

345.201181 45.201847 45.201555

09.139856 09.139828 09.139477

445.200705 45.198690 45.198816

09.143692 09.143832 09.143833

A smart textile can …

Monitor man, the environment and itselfDetect unusual conditionsDetect when things risk to get out of handPrevent things from happeningProtect against accidentsMonitor the impact of eventsProvide early assistanceSupport and follow up rehabilitation

www. .eu

Coordination action for enhancing the breakthrough of intelligent textile systems (e-textiles and wearable Microsystems)

www. .org

COLAE: Commercialisation Clusters of OLAE