Switches
Switches as alternative to keyboard
Description
There are many types available, ranging from single switches (where the switch is either on or off) up to multi-position switches. To emulate a keyboard, a switch must be used in conjunction with hardware to interface with the computer and software which offers the user choices. There is a wide variety of available switches, activated by many different actions. Methods include various levels of direct pressure, tilting, detection of eyebrow movement and sucking and/or blowing through a tube connected to the switch. The range of options is vast. While emphasis here is on using switches to operate computers, they can also be used for other purposes. Examples include operating toys, household appliances and environmental controls.
People who have very severe limitation of movement are potential candidates for this type of device. The switch which will best suit a particular individual will depend on the nature and extent of that person’s control over body movements. Assessment by an occupational therapist or physiotherapist is important. It is necessary to determine both the most suitable switch(es) for an individual and placement of switches.
Advantages
In combination with software and additional hardware, a switch can allow a person who has very limited, or even no, physical movement to operate a computer. The person can use the equipment to do tasks usually associated with computers-word processing, using the Internet, programming, etc. As mentioned above, the technology can also be used to provide environmental control-turning lights on and off, adjusting an air conditioner, answering the doorbell and so on.
Disadvantages
Even when used in conjunction with predictive software, speed may be slow.
Computer interface hardware and software for switches
Description
The device forms an interface between one or more switches and the computer. In effect, the switch(es) and interface hardware are used instead of the keyboard.
To allow instructions to be issued to a computer via switches, it is necessary for purpose-designed software to be provided. In this situation, the use of an on-screen keyboard is very important. In its most basic form, this method of input can be very time consuming. A large variety of enhancements, however, can improve efficiency and reduce fatigue. Wide use of the mouse and other pointing devices has also done much to help.
Advantages – As for switches
Disadvantages – As for switches
