BBC Knowledge Asia Edition

SMART MATERIALS AND

SELF-REPAIRING PAINT

The ability to design materials
with particular physical properties
is one of the things we’ve built
our world around. For thousands
of years we’ve made our homes
from brick, concrete, steel and
glass, inventing new materials
where we couldn’t find natural
ones that fitted the bill. These
days, we know enough physics
and chemistry to design materials
with more specific properties,
and the growth of nanomaterials
like graphene, composite
polymers and new ceramics
seems unstoppable. And now
we’re seeing the development of
‘smart materials’ that adapt to their
environment.
Smart products such as
self-dimming, self-cleaning
glass and self-healing paint are
already available. Some of these
materials are quite complex
internally. In electrothermic glass,
several stacked porous layers are
printed on top of each other and
sandwiched between two glass
panels. Low-voltage electrical
charges activate an electrochromic
layer which changes colour from
clear to dark. Once you have this
glass in place, you can control it

THE NEXT BIG THING

BILL THOMPSON

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FROM THE LAB X-Ray... meet XBox

WHAT’S GOING ON?

Scientists at the Washington

University School of Medicine in

St Louis, Missouri have equipped

an X-ray machine with sensors

and software that were originally

developed for the Microsoft Xbox’s

motion-sensing Kinect system.

WHY DID THEY DO THAT?

Because small children are basically

rubbish at sitting still, which means

that when kids need an X-ray they

often end up having three or four,

because they kept moving around

when it was being taken. That, of

course, exposes them to more

radiation than is generally considered

a good thing. But the Kinect’s motion

sensors enable a radiographer outside

the room to make sure the child is

sitting still before snapping an X-ray.

WHY USE KINECT?

Because it’s affordable, and because

its sensors can also detect the

thickness of body parts. As kids vary

greatly in size, radiographers need

to calibrate their X-ray machines

accordingly. Until now, this has meant

brandishing a pair of steel callipers

and scaring little Timmy half to death

• but with Kinect’s sensors, all the
  information needed is already to hand.

The Lumenus jacket works with Google Maps to keep cyclists safe

Blurred X-ray images could be a thing

of the past with the new Kinect system

The future’s so bright, Bill’s gotta wear

electrothermic shades

in a variety of ways via a building

management system. But smart

materials will soon be used

beyond buildings and vehicles.

Researchers like Rain Ashford at

Goldsmiths University of London

have been exploring ways to

link sensors and fabrics to build

genuinely wearable computers

that respond to the user’s

environment or emotions.

As we build smarter materials,

they’ll be used to develop more

advanced fabrics. A good example

is an LED-equipped jacket from

a startup called Lumenus. This

quite literally points the way

forward: the jacket interfaces with

Google Maps on a cyclist’s phone

to provide visual cues to both

the rider and surrounding traffic,

with turn signals and brake lights

built-in. Here, the waterproof

electronics are added to the jacket,

but the same technology that

delivers electrochromic glass could

also create fabrics that glow on

demand. Build in a solar panel

and wireless connections, and you

have a self-contained node, part of

the Internet of (Wearable) Things.

Clothing that acts as a portable

display is one thing, but we’ll

eventually reach the point

where the physical properties

of a nanomaterial merge with

computational capability, where it

becomes more useful to describe

the fabric your clothes are made

out of as a computer in its own

right rather than a piece of

clever mechanical engineering.

A branch of cosmology called

‘digital physics’ takes this to its

logical conclusion and argues

that the Universe as a whole is

itself a computer, and that all

behaviour can be described in

this way. But you don’t need to

go that far to accept that your if

your raincoat reconfigures itself

when it’s about to start pouring,

it could reasonably be called a

computer. ß

PHOTO: GETTY