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218 HANDBOOK OF ELECTRONIC ASSISTIVE TECHNOLOGY

will argue that the informed, methodical approaches to specialist EAT provision, covered
elsewhere in the book, do not currently include all the elements required to achieve suc-
cessful outcomes.

The Technology

It was in the 1990s when the possibilities associated with using technology to enhance inde-
pendent living were dawning, and home automation was beginning to evolve from a market
concept to reality. The commercial potential for home automation had already been demon-
strated much earlier by the success of the simple, low-cost powerline-based X10 system (see
Powerline Technologies), but the weaknesses and limitations inherent in this system made
it unsuitable for consideration in such safety-critical situations. It was the emergence of off-
the-shelf, sophisticated, home automation technology – the bus-based home automation
systems – that offered the necessary levels of sophistication and robustness to potentially
support complex needs. Once this had been realised and demonstrated, in principle by the
BESTA project in Norway between 1993 and 1994 (Bjornby, 2000), various groups began
to explore the possibilities that smart home systems offered for independent living. These
explorations will be reported later in the chapter, but first we will summarise the technologi-
cal developments, focusing heavily on the bus-based systems that kick-started the field, and
which still represent the most developed body of knowledge on the subject today.
The American Association of House Builders coined the phrase ‘smart home’ in 1984
and the concept of the smart home as it is generally understood began to materialise
shortly after this. It was part of the continuous evolution of the field bus technologies
developed for process control, which in turn had evolved from the logic-based process
control technology originally developed in the 1970s.
The continuing miniaturisation and related increase in complexity, coupled with
decreasing cost of microelectronics, offered new possibilities in process control. It made
it possible to incorporate microprocessors within local devices rather than relying on cen-
tralised computer control, thereby making systems more responsive and resilient. This led
to a proliferation of field bus systems, first in industrial process control, then in areas such
as building management systems and home automation.
An early implementation of localised process control, using integrated circuit tech-
nology, was the TDC2000 system developed by Honeywell in 1975, although this wasn’t
truly distributed intelligence. In 1979 Modicon, renamed Schneider Electric, introduced
Modbus, which was a serial bus allowing a master to control up to 247 addressable slaves.
This was followed by a proliferation of field bus systems with true distributed intelligence.
Bitbus was developed by Intel and in 1983 they created the Bitbus controller; Bosch intro-
duced CAN in 1982, and released the protocol in 1987, followed closely by the first control-
ler chips from Intel and Philips, with the 1988 BMW 8 Series being the first production car
to feature a CAN-based system; Process-Data developed P-Net in Denmark in 1983 with
the first product launched in 1984; and in 1986 the German Department of Education and
Research initiated development of Profibus, which was formerly launched in 1989.