textiles with electronic functionality
TRANSCRIPT
Textiles with Electronic Functionality
Professor Tilak Dias Advanced Textiles Research Group
School of Art and Design 07th March 2013
Smart & Interactive Textiles (SMIT)
• New emerging sector of textiles
• Market growth rate is forecasted at 40% annually and to reach US$2.5 billion by 2021
• Although still in its infancy, the US market for SMIT was $70.9 million in 2006, and $391.7 million in 2012
Smart and interactive textiles (SMIT) can sense electrical, thermal, chemical, magnetic or other stimuli in the environment and adapt or respond to them, using functionalities integrated into the textile’s structure.
(Foresight Horizon Scanning Centre, www.bis.gov.uk/foresight, URN: 10/1252 – Technology
and innovation futures)
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Introduction
• Good tensile recovery properties
• Superior conformability and excellent skin contact with knitted structures
• Breathability; the structures are air permeable hence better comfort
• Freedom of constructing structures with different pattern elements
Textile structures are created by binding fibres (physical binding)
Why use textiles to create interactive systems?
General properties of textiles (fibre structures)
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• Robust and easily programmable manufacturing systems
• High production speeds
• Large area structures
Key manufacturing features
Introduction
Capability of creating comfortable wearable electronics
• Efficient sensors (vital signs, posture) and actuators (interaction) on the body
• Ability for placing sensors and actuators accurately
• Uninterrupted monitoring
• Possibility of providing therapy during day to day activities
Advantages of using textiles to develop SMITs
Smart & Interactive Textiles
Capability of creating large-area electronic systems
• Sensor systems for ‘ambient intelligence’
• Lighting and heating/cooling systems
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SMART & Interactive Textiles
Core Elements
Transducers
Intelligent Signal Processing
Actuators
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Advantages of this technology
• Precision positioning of fibers in 3D space
• Ability to create seamless 3D structures
• Multilayer structures
• Ability to process different types of yarns
Computerised flat-bed knitting technology to create e-textiles
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Electrically Active Knitted Structures
Electro Conductive Area (ECA)
Concept of creating textiles with significant electrical properties: Incorporate conductive elements into the structure
Knitted structure
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Use of electro-conductive fibres/yarns
Metal yarns (mono-filament and multi-filament)
Metal deposition yarns
Carbon fibres and yarns
Conducting polymeric yarns
PA yarn vacuum coated with Ag nano layer
Creation of ECA
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Unit Cell - Stitch Electrical Equivalent Circuit
RH
RH
RL RL
Modelling
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Equivalent resistive mesh circuit of the ECA
Dimensions of the ECA: m courses & n wales
05
1015
20
0
10
2010
12
14
16
18
20
22
Relationship between equivalent resistance and stitch density of ECA
Assumption: Lleg = 2 Lhead
Equ
ival
ent
resi
stan
ce in
KΩ
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Garment for vital sign monitoring
Study of knitted electrodes - Objectives
• Quantify signal to noise ratio dependence on knitted electrode pressure
• Compare performance of a number of conductive yarns for electrode construction
• Determine the design for the ECG garment design
Garment for vital sign monitoring
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Standard Ag-AgCl Electrodes with conductive gel
Garment for vital sign monitoring ATRG_TD
Electrodes knitted with silver yarn (dry state)
Garment for vital sign monitoring ATRG_TD
Sensor sock for monitoring of 3D foot orientation
Knitted stocking with:
• Knitted resistive stretch (KRS) sensors
• Knitted conductive pathways
• Seamless knitted garment
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Sensor sock for monitoring of 3D foot orientation
Performance of the Sensor Sock
Sensor sock with kinematic markers used for trials Sensor output and scaled kinematic signal against time
for a single walking trial
Kinematic signal
KRS sensor output
Heel lift Toe off Heel strike
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Technology is based on the encapsulated area not exceeding 110% of the thread thickness
Electronically active fibres/yarns
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Vision
The development of the technology for fabricating
electronically active intelligent fibres/yarns which
will be the basic building blocks of the next
generation ‘Smart and Interactive Textiles (SMIT)’
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Involves encapsulating micro-devices with a flexible hermetic seal for mechanical, thermal and electrical protection
Electronically Active Fibre/Yarn Technology
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Sensor Fibres
• Strain measurement • Temperature measurement • Fluid/gas measurement • Radiation sensing • Light measurement • Acoustic measurement • Motion detection • Pressure measurement
• RFID • Light emitting • Vibration • Magnetic • Transmission • Peltiers
Active Fibres
Potential of the core technology
• Micro-controllers • Micro-processors
Intelligent Fibres
SMIT
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Thank You
Contact details: Professor Tilak Dias Advanced Textiles Research Group Tel.: 0115 848 6518 Email: [email protected]
Advanced Textiles Research Group School of Art and Design Nottingham Trent University Nottingham NG1 4BU http://twitter.com/#!/advancedtextile www.facebook.com/ntuadvancedtextiles www.ntuadvancedtextiles.wordpress.com
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