Page 119 - Handbook of Electronic Assistive Technology

Chapter 5 • Alternative Access Technologies 107

FIGURE 5-1 Assistive technology access model�
is being used and the activity and environment in which it is being used. All these aspects
must be taken into account when considering access to assistive technologies. Cook and
Hussey regard the complete system in terms of the Human Activity Assistive Technology
model (Cook and Hussey, 1995), while Zabala, from a special education perspective, pro-
poses the Student, Environment, Task, Tools Framework, which also emphasises the need
to adopt a holistic view of assistive technology (Zabala, 2005).

Device

The device refers to the electronic assistive technology device itself: the computer, voice
output communication aid, environmental control system or powered wheelchair.
Control Site

The control site is the body part or physical action that the user employs to operate the
technology; this can be a finger and/or a hand, foot, knee, elbow, voice, mouth, head or
eyes, and more. The most common control sites are finger/thumb/hand, as used to access
touchscreen, keyboard, mouse or trackpad, although some commentators suggest that
recent advances in speech recognition may result in speech becoming the dominant con-
trol interface in the future for mainstream digital technologies.

Control Interface

The control interface refers to the input device and interface, such as the touchscreen, key-
board, mouse, joystick or eye-gaze camera (Fig. 5-2). The control interface is bidirectional