Assistive technology

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Assistive Technology (AT) is a generic term that includes assistive, adaptive, and rehabilitative devices and the process used in selecting, locating, and using them. AT promotes greater independence for people with disabilities by enabling them to perform tasks that they were formerly unable to accomplish, or had great difficulty accomplishing, by providing enhancements to or changed methods of interacting with the technology needed to accomplish such tasks. According to disability advocates, technology, all too often, is created without regard to people with disabilities, and unnecessary barriers make new technology inaccessible to hundreds of millions.

Universal (or broadened) accessibility, or universal design means excellent usability, particularly for people with disabilities. But, argue advocates of assistive technology, universally accessible technology yields great rewards to the typical user; good accessible design is universal design, they say. The classic example of an assistive technology that has improved everyone's life is the "curb cuts" in the sidewalk at street crossings. While these curb cuts surely enable pedestrians with mobility impairments to cross the street, they have also aided parents with carriages and strollers, shoppers with carts, and travellers and workers with pull-type bags, not to mention skateboarders and inline skaters.

Consider an example of an assistive technology. The modern telephone is not accessible to people who are deaf or hard of hearing. Combined with a text telephone (also known as a TDD [Telephone Device for the Deaf] and in the USA generally called a TTY[TeleTYpewriter]), which converts typed characters into tones that may be sent over the telephone line, the deaf person is able to communicate immediately at a distance. Together with "relay" services (where an operator reads what the deaf person types and types what a hearing person says) the deaf person is then given access to everyone's telephone, not just those of people who possess text telephones. Many telephones now have volume controls, which are primarily intended for the benefit of people who are hard of hearing, but can be useful for all users at times and places where there is significant background noise.

Another example: calculators are cheap, but a person with a mobility impairment can have difficulty using them. Speech recognition software could recognize short commands and make use of calculators a little easier. People with cognitive disabilities would appreciate the simplicity; others would as well.

Toys which have been adapted to be used by children with disabilities, may have advantages for "typical" children as well. The Lekotek movement assists parents by lending assistive technology toys and expertise to families.

Telecare is a particular sort of assistive technology that uses electronic sensors connected to an alarm system to help caregivers manage risk and help vulnerable people stay independent at home longer. A good example would be the systems being put in place for senior people such as fall detectors, thermometers (for hypothermia risk), flooding and unlit gas sensors (for people with mild dementia). The principle being that these alerts can be customised to the particular person's risks. When the alert is triggered, a message is sent to a carer or contact centre who can respond appropriately. The range of sensors is wide and expanding rapidly.

Technology similar to Telecare can also be used to act within a person's home rather than just to respond to a detected crisis. Using one of the examples above, unlit gas sensors for people with dementia can be used to trigger a device that turns off the gas and tells someone what has happened. This is safer than just telling an external person that there is a problem.

Designing for people with dementia is a good example of where the design of the interface of a piece of assistive technology (AT) is critical to its usefulness. It is important to make sure that people with dementia or any other identified user group are involved in the design process to make sure that the design is accessible and usable. In the example above, a voice message could be used to remind the person with dementia to turn off the gas himself, but whose voice should be used, and what should the message say? Questions like these must be answered through user consultation, involvement and evaluation.

1 Assistive technology products
2 See also
3 Further reading
4 External links

[edit] Assistive technology products

[edit] Accessing the keyboard

Hardware

Height-adjustable trolley. Allows precise adjustment, via a handle, of a computer to the correct height - even when fully loaded with equipment.
Adjustable keyboard and monitor arms. Attaches to a table and swings out to the correct height.
Footrests. If the user’s feet are dangling down from a seat that is too high they can help to maintain sitting balance and achieve good hand control.
Wristrests. Stabilises the arm.
Arm supports. Take the weight of the arm and let the user move across the keyboard to access the keys.
Keyguards. It fits over the keyboard to help prevent unintentional keypresses.
Ergonomic keyboards. Reduce the discomfort from injuries related to excessive keyboard use (wristrests are often built in as well).
Chording keyboards. Have a handful of keys (one per digit per hand) to type by ‘chords’ which produce different letters and keys.
Expanded keyboards. Keys are larger and more widely spaced.
Compact and miniature keyboards. A smaller version of the standard keyboard.
Dvorak alternative keyboard layout. An ergonomic keyboard layout, where the most common keys are located at either the left or right side of the keyboard.
Height-adjustable computer table

Software

Sticky keys is a feature of Microsoft Windows 95 onwards and Mac OS X operating systems. Allows characters or commands to be typed without having to hold down a modifier key (Shift, Ctrl, Alt) while pressing a second key.
FilterKeys is a feature of Microsoft Windows 95 onwards. Instructs the keyboard to ignore brief or repeated keystrokes.
FilterKeys (Ignore repeated keystrokes) is a feature of Microsoft Windows 95 onwards. Adjusts the amount of time that elapses before a character repeats when you hold down a key.
FilterKeys (Ignore quick keystrokes and slow down the repeat rate) is a feature of Microsoft Windows 95 onwards. Adjusts the speed at which a character repeats when you hold down a key.
ToggleKeys is a feature of Microsoft Windows 95 onwards. A high sound is heard when the CAPS LOCK, SCROLL LOCK, or NUM LOCK key is switched on and a low sound is heard when any of those keys are switched off.

[edit] Accessing the mouse

Hardware

Wristrests and supports. Wristrests support the hand so that there is less strain on the wrist; arm supports support the arm yet still permit free movement.
Keyboard shortcuts. A combination of keys is used for operations commonly done using the mouse.
Rollerballs. An upside-down mouse where the ball is moved directly with the fingers (or foot, nose, elbow etc) to control the mouse pointer.
Joysticks. The stick is moved directly with the fingers (or foot, nose, elbow etc) to control the mouse pointer.
Graphics tablets. The stylus pen, linked to the tablet, is moved with the hand to control the mouse pointer.
Touch pads. Flat touch sensitive surface operated with the finger to control the mouse pointer.
Touch screens. The user can touch objects directly on the screen to move them around.
Head control. Use head movement to control the mouse pointer.

Software

Double-click speed is a feature of Mac OS X and Microsoft Windows.
ClickLock is a feature of Microsoft Windows. Locks a mouse button down so that items can be dragged around the screen.
Mouse speed is a feature of both Mac OS X and Microsoft Windows. Sets how far and fast the pointer moves on the screen.
Pointer size is a feature of Microsoft Windows and Mac OS X. Changes can be made to the size, colour or shape.
MouseKeys is a feature of Mac OS X and Microsoft Windows 95 onwards. Configures the numeric keypad at the right-hand side of the keyboard to control the mouse pointer.
Macros is a feature of Microsoft Word. A particular sequence of keyboard operations are ‘recorded’ and then ‘played back’ by pressing a combination of keys.

[edit] Switch access and switches

Switches allow access to computers for people with severe physical or cognitive difficulties. Mimics a keyboard keystroke or mouse click.
Switch interface. Used as an interface to connect a switch to the computer.
Switch mounting. Used to mount a switch (sometimes in conjunction with a mounting plate).
Switch accessible software. Software which is accessible via a switch.

[edit] Learning difficulties

Hardware

Keyboards with lowercase keys
Keyboards with big keys
Symbols based software
Touchscreen
Word processor with speech software

Software

Age appropriate software
Cause and effect software
Hand-eye co-ordination skills software

[edit] Visual impairment

Hardware - choice of appropriate hardware will depend on the user's level of functional vision.

Full keyboard stickers. High-contrast, enlarged print adhesive keyboard stickers - white on black, black on white and black on yellow sets available.
Large print keyboard. High-contrast, enlarged QWERTY keyboards - white on black, black on white and black on ivory versions available.
Locator dots. Help locate ‘home’ keys, i.e. F and J, on the keyboard.
Wheel mouse. Moves mouse pointer, plus middle wheel button is used to scroll up and down.
Large screen monitor. Produces a larger-than-normal image.
Adjustable task lamp. Lamp, using fluorescent bulb, shines directly onto the paper and can be adjusted to suit.
Copyholder. Holds printed material in near vertical position for easier reading and can adjusted to suit.
Closed Circuit Television system (CCTV)/Video Magnifier. Printed materials and objects are placed under a camera and the magnified image is displayed onto a screen.
Modified cassette recorder. To record a lecture, own thoughts, ideas, notes etc.
Desktop compact cassette dictation system. To allow audio cassette playback with the aid of a foot pedal.
Fuser. To produce tactile materials, e.g. diagrams, by using heat and special swell paper.
Standalone Reading Aid. A unit which integrates a scanner, Optical Character Recognition (OCR) software and speech software. The printed document is scanned and read by the same machine.
Scanner. A device used in conjunction with Optical Character Recognition (OCR) software. The printed document is scanned and converted into electronic text, which can then be displayed on screen as recognisable text.
Refreshable Braille display. An electronic tactile device which is placed under the computer keyboard. A line of cells, that move up and down to represent a line of text on the computer screen, enables the user to read the contents of the computer screen in Braille.
Electronic Notetaker. A portable computer with a Braille or QWERTY keyboard and synthetic speech. Some models have an integrated Braille display.
Braille embosser. Embosses Braille output from a computer by punching dots onto paper. It connects to a computer in the same way as a text printer.
Perkins Brailler. To manually emboss Grade 1 or 2 Braille.

Software - choice of appropriate software will depend on the users level of functional vision.

Customised Microsoft Windows. Changes the desktop, short-cut icons, menu bars and scroll bars.
Customised mouse pointers and toolbars. Changes the size, colour and/or shape of mouse pointers and the size of toolbars.
Screen magnifier. Enlarges the image on the computer screen. The level and type of magnification can be customised. Some programs also have supportive synthetic speech.
Screen reader. Converts what is happening on the computer screen into synthesised speech or braille via a refreshable braille device.
Optical Character Recognition. Converts the printed word into synthesised speech, via a scanner.
Braille translation. Converts the printed word into Braille, which can then be embossed via a Braille embosser.
Touch typing.
Keyboard shortcuts, such as Ctrl+S, Alt+F4, F7. A combination of keys are used for operations commonly done using the mouse.

[edit] Alternative & Augmentative Communication (AAC)

Low-tech systems. Simple paper or object based systems, i.e. do not require a battery.
Light-tech systems. Simple voice output devices, which require a battery; although no sophisticated charging mechanism is required.
High-tech systems. Sophisticated voice output devices, which require a battery, as well as training and ongoing support.

[edit] D/deafness, Hearing loss

Audiometer
Fire alarm paging system
Loop system (portable and fixed)
Radio aids
Textphone
Televisions with Teletext
VCRs that can read and record subtitles
Vibrating fire alarm (for use when asleep - place under pillow)
Door bell lighting system

[edit] Specific learning difficulties

Diagnostic assessment software
Spellcheckers
Study skills software
Touch typing software
Visual mapping software
Word prediction software

[edit] Voice Recognition

There are many voice recognition programs. Dragon Naturally Speaking is one of the famous ones' MS Office also has this capability.

This section is a stub. You can help by expanding it.

[edit] Others

Wakamaru provides companionship, reminds users to take medicine and calls for help if something is wrong.
Cosmobot is part of a play therapy system designed to motivate children to participate in therapy.

[edit] See also

[edit] Further reading

Behrmann, M. & Schaff, J.(2001). Assisting educators with assistive technology: Enabling children to achieve independence in living and learning. Children and Families 42(3), 24-28.

Bishop, J. (2003). The Internet for educating individuals with social impairments. Journal of Computer Assisted Learning 19(4), 546-556. Available as a free download

Cain, S. (2001). Accessing Technology - Using technology to support the learning and employment opportunities for visually impaired users. Royal National Institute for the Blind. ISBN 1-85878-517-0.

Cook, A., & Hussey, S. (2002). Assistive Technologies - Principles and Practice, 2nd Edition. Mosby. ISBN 0-323-00643-4

Franklin, K.S. (1991). Supported employment and assistive technology-A powerful partnership. In S.L. Griffin & W.G. Revell (Eds.), Rehabilitation counselor desktop guide to supported employment. Richmond, VA : Virginia Commonwealth University Rehabilitation Research and Training Center on Supported Employment.

Lahm, E., & Morrissette, S. (1994, April). Zap 'em with assistive technology. Paper presented at the annual meeting of The Council for Exceptional Children, Denver, CO.

Lee, C. (1999). Learning disabilities and assistive technologies; an emerging way to touch the future. Amherst, MA: McGowan Publications.

McKeown, S. (2000). Unlocking Potential - How ICT can support children with special needs. The Questions Publishing Company Ltd. ISBN 1-84190-041-9

Nisbet, P. & Poon, P. (1998). Special Access Technology. The CALL Centre, University of Edinburgh. Available as a free download The CALL Centre. ISBN 1-898042-11-X

Nisbet, P., Spooner, R., Arthur, E. & Whittaker P. (1999). Supportive Writing Technology. The CALL Centre, University of Edinburgh. Available as a free download The CALL Centre. ISBN 1-898042-13-6

Rose, D. & Meyer, A. (2000). Universal design for individual differences. Educational Leadership, 58(3), 39-43.

Orpwood, R. Design methodology for aids for the disabled. J Med Eng Technol. 1990 Jan-Feb;14(1):2-10. | PubMed ID: 2342081

Adlam, T. et al. The installation and support of internationally distributed equipment for people with dementia." IEEE transactions on information technology in biomedicine (1089-7771) yr:2004 vol:8 iss:3 pg:253-257 | download from IEEE (694k PDF)