Alternative keyboards
Onscreen keyboards
Switches
Mouse emulation devices
Speech-to-text software
Ergonomic keyboards can help people who experience pain when using conventional keyboards. Keys are typically set in two convex banks and angled to produce a more comfortable position for the wrists. They vary according to the degree of adjustment provided.
Small keyboards can be helpful for people who have good motor control but for whom larger movement is difficult or painful. The size of individual keys and the overall unit is smaller than usual.
Expanded keyboards can help people who have poor motor control. One approach is to use larger keys–say 2.5 cm square (see BigKeys under Examples). Another is to use a membranous surface and an overlay (see Intellikeys in Examples). Associated software allows a given area of the surface to represent a chosen key.
This software displays a representation of the keyboard on the screen. Characters are selected with a mouse or mouse emulation device. They can be set up to meet individual needs and can allow selection by clicking (or equivalent) or by dwelling on the character for a set time. Onscreen keyboards can be used to operate standard computer applications.
Switches come in a vast range of styles and are used by people with very limited movement. They may be activated by such methods as pressure, tilting, or air pressure (from sucking a tube, blinking or any other movement). Switches are used to operate such products as onscreen keyboards and scanned arrays.
Manufacturers include Ablenet, Inclusive Technology, Prentke Romich and Rehabilitation Engineering. See http://www.abilitycorp.com.au or http://regencyrehab.cca.org.au or http://www.spectronicsinoz.com for Australian suppliers. Also Technability at http://www.technability.com.au/
These include options such as joysticks and head-mounted pointing devices. Joysticks suit some people who lack finer motor control. A joystick can be used instead of a mouse or with specialised software such as onscreen keyboards. A head pointer is another useful device. It is connected to the computer via a cable or infra-red beam. The mouse pointer moves in accordance with the user's head movements. 'Clicking' is done by activating a switch which can be available in many types. Head-mounted pointers are generally used with onscreen keyboards.
Speech-to-text software processes speech. The user talks into a microphone connected to the computer's sound card or USB port. Desktop and headset microphones (including wireless) are available. Both text and instructions can be dictated to the computer, although many users choose to use alternative methods for mouse control. While quite high levels of accuracy can be achieved, a high-specification computer with a large amount of RAM is needed and the individual user must spend some time 'training' the software. Speech input is highly relevant to people who have difficulty using a keyboard and other manual input methods. As technology improves it will be used more widely, for example by people who want to use a computer while driving. It may also become valuable for use with very small devices where keyboard input is tedious.