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HOME AUTOMATION INTRO
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The automated home concept has been doing the rounds since at least the
1920s and has been a staple ingredient in sci-fi and futurist movies, TV
sitcoms and documentaries ever since, but maybe it’s closer to reality than you
think. A brief trawl on the net for ‘home automation’ brings up hundreds of web
sites, advertisements, magazines and articles, many confidently proclaiming
that it has already arrived, for a fortunate few it has but for the rest of us
the truth is a little more complicated.
Even something as apparently straightforward as defining what home
automation actually means is difficult. Everyone involved has their own ideas
but once you eliminate the hype and wishful thinking it boils down to this:
it’s the facility to control – either centrally or remotely -- a wide range of
household appliances and environmental, entertainment, communications and
security systems.
In home automation nirvana lights switch on when you enter your climate
controlled rooms, the kettle talks to the toaster to prepare your breakfast,
the fridge knows when you’ve run out of eggs and milk and orders up new
supplies and you can listen to music, watch movies, surf the net and see who’s
at the front door from every room in your house.
Whilst it is possible to do all that and more right now, it is still a
very long way from being a convenient, one-stop, off-the-shelf technology.
Moreover it is likely to remain that way until every electrical and electronic
gadget -- and that includes those kettles and toasters -- can be linked
together and communicate with other devices, but we are getting there!
The history of home automation is littered with lots of clever (and
plenty of plain stupid) attempts to establish a set of common technical
standards and protocols to connect household appliances together but almost
without exception they have failed through a lack of interest, commercial
rivalry, general flakiness and the scary big one, cost! Nevertheless tens of
thousands of homes around the world testify to the fact that it can be done,
along with countless others that are either partially or semi automated. The
good news is that with every passing year it’s getting easier, and cheaper, but
anyone considering automating their home would do well to learn from the
mistakes of the past.
Over the years numerous highly automated homes have been built but
until fairly recently it was only for the rich and famous. Back in the 70s and
80 the high-tech homes of the likes of Paul Newman and Stirling Moss became
showcases for what was possible at the time. Footage of tellies emerging from
wall panels, and automatic lighting and heating systems were regularly aired,
but these were outrageously expensive, custom built, high-maintenance
installations and not the sort of thing the average Joe could aspire to. More
recently we’ve been treated to occasional glimpses of Bill Gates’ futuristic
new home and this is even further removed from the reality of the average
three-bed semi.
Home automation technology for the masses was first touted in the mid
1980s when several companies drew up plans for a so-called home ‘bus’ system. A
bus in this context is simply a cable network, running throughout the home,
carrying telemetry and control signals to and from connection points and a
mysterious central black box that looks after the whole shebang. Just about
everyone who’s anyone in the electronics industry had a stab at it. Philips,
Thomson and Sony devised a system called D2B (Domestic Digital Bus), several
Japanese companies, including Matsushita (the parent company of Panasonic and
Technics) created HBS (the Home Bus System) a consortium of Europe and
electronic companies tried their luck with something called Esprit and not
wanting to miss out on the fun the Americans came up with CEBus (Consumer
Electronics Bus).
By the early 90s it was apparent that no one system was going to
prevail and the cost of adapting everyday consumer products to this kind of
application was prohibitive. There were several half-hearted attempts to make
the rival technologies compatible with one another but one by one they fell by
the wayside. Only one has survived, albeit in a highly modified form, CEBus,
and the communication system it uses, CAL (common application language) has
been adopted as an international standard for controlling ‘Home Network
Products’, but so far it has attracted little attention in the wider world.
The big turn off with any bus-based system is all the cabling involved
and the difficulty in ‘retro-wiring’ older properties. This undoubtedly
explains why so many of the most successful home automation projects are in
newly built houses, where the cabling and control systems can be incorporated
into the design at a very early stage, preferably long before the first brick
has been laid.
So where does that leave those living in older homes that may not be
amenable to being laced with several kilometres of cables? The truth is
cabling, and lots of it is still a prerequisite of any current home automation
system, but maybe not for much longer. The wired bus network is on the way out
and there’s no longer any need to have a dedicated cable running from room to
room, carrying control signals, (though many purists maintain cable
installations are simpler, cheaper and more reliable).
The most successful alternative method so far is ‘X10’, which uses
household mains wiring to distribute control signals to remote switching and
sensing modules. In a little over three years X10 has grown from a relatively
simple gadget for remotely switching mains appliances on and off to a highly
sophisticated system, with dozens of compatible devices available for
controlling lights, central heating systems, home theatre or indeed any mains
powered device. X10 setups are comparatively cheap and can be easily expanded
to include computer control, telephone and Internet access plus integration
with a wide range of security and video surveillance devices.
The next generation of products, now just starting to come on to the
market does away with wires altogether, for the distribution of control and
telemetry signals at any rate. Wireless networking is the new flavour of the
month after the initial flurry of formats two standards have emerged, known
their friends as 802.11b (or ‘Wi-Fi’) and Bluetooth.
Wi-Fi began life as Apple’s Airport wireless networking system for
laptops and PCs; it’s capable of handling moderately large volumes of data (up
to 100 megabits per second) over distances of between 50 and 100 metres. The
band of frequencies used for Wi-Fi (2.4GHz) is also used by a range of audio
and video distribution gadgets, enabling picture and sound signals from a
single source (TV tuner, DVD player, home surveillance system, etc.) to be sent
around the home to TVs and monitors, and all without wires. Incidentally
although these devices share the same frequency band they are supposed not to
interfere with one another, though problems can arise if several systems are in
close proximity; if you are thinking of going down the wireless route check
what the neighbours are up to…
A Wi-Fi local area network or ‘LAN’ allows PCs to exchange files and
share printer and Internet connections. From there, it is a very short step to
use a PC to operate or respond to wirelessly controlled remote switches and
sensors within a home automation network. By the way, the original 802.11b
standard is due to be phased out within the next couple of years and replaced
by 802.11a (don’t ask…), which allows even higher data transmission speeds –
suitable for streaming high quality video -- plus improved security and better
immunity to interference.
Bluetooth is also a wireless system but it differs from Wi-Fi in that
it’s short-range (typically 10cm to a metre) and a good deal slower (up to
1mb/sec). It is designed to allow small portable devices to communicate with
one another; so far it has mostly been used by things like cordless earpieces
for mobile phones and enabling laptops and PDAs to exchange data. However, it’s
relatively easy to add Bluetooth connectivity to almost any product at the
design stage and this would overcome one of home automation’s most fundamental
problems, namely a simple and standardised, plug and socket free communications
link.
There’s absolutely no doubt that wireless control and networking is the
way forward but right now most home automation installations are still heavily
dependent on cables, and will remain so for some time. But whatever the
technology planning is vitally important, to minimise disruption, now and in
the future. A system should be able to cope not just with your current need,
and all of the other gizmos that you’re planning to buy, but also with
technologies still to come. Experts in the field use a trick called ‘cable flooding’, which basically means
providing capacity and mains sockets – don’t forget them -- for everything you
are likely to have in the next ten years, then doubling it!
---end---
Ó R. Maybury 2002,
1810
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