Assistive Technology Approaches for Improved PC Access
Edward S. Rosenthal
Whatever your impairment might be, it doesn't have to stop you from using the computer. Discover how assistive technology can work for you.
Assistive technology explained
The field of Assistive Technologies (AT) is quite broad. It includes everything from basic devices like a magnifying glass through high-tech devices that allow people to use retinal eye movement to control the actions of a mouse on a PC. Certainly, not all assistive technologies focused on providing improved or increased computer access. However, over the last 20 years the number of available technologies to assist people with PC access (and computer access in general) has grown exponentially. When coupled with Universal Design trends in software what we are hopefully seeing is the broadening of "inclusive" design strategies, as well as expanding employment opportunities for people with disabilities. Universal Design is described as many things, but in my opinion a good definition would be, "By focusing on access strategies and product design, one is able to provide the greatest possible use scenario and therefore the greatest amount of benefit to the general population."
While many people are familiar with the greatest PC-based AT and related categories we thought it would be helpful to provide a general overview of various technologies intended to provide improved access for individuals with certain types of disabilities. This information is not by any means intended to be exhaustive, and in any instance where a specific product is mentioned this is not intended to provide an endorsement of the product or commented on its merits rather we provide a specific example that will make it easier for someone wishing to do follow-up research to explore specific product category. It would also be important that anyone wishing to follow up on specific product areas should evaluate the "age appropriateness" of any technologies being considered. Many assistive technologies require cognitive sophistication on the part of the user; and most require patience to master a specific AT. The disability categories and associated product categories are not presented in any specific order.
Mobility challenges present some obvious and not so obvious difficulties when one is hoping to access computer technology. In general, computers have been designed to support a graphical user interface (GUI) that anticipates use of the keyboard and/or mouse. As the category of mobility challenges spans everything from mild repetitive stress injury (RSI) to profound quadriplegia, access strategies vary significantly but will primarily focus on replacing or augmenting keyboard and mouse access. RSI is also referred to as 'work-related musculoskeletal disorders' by the Occupational Safety and Health Administration (OSHA).
Four general strategies present themselves when looking at the available assistive technology keyboard strategies: ergonomic, one-handed, on screen, Dvorak. Since we've seen such a large increase in the number of computer users dealing with RSI and related issues one of the primary approaches to mitigate the symptoms of repetitive stress injury is to provide the user with an ergonomic keyboard. The general concept of using an ergonomic keyboard is to position the user's hands in a less stressful, more ergonomic position. Simple ergonomic keyboards have a traditional look but may have the keyboard position as two distinct areas, and one uses an angled approach of the wrist for typing. Microsoft makes a number of keyboards of this type including the Microsoft Wave keyboard design Microsoft Hardware.
Other companies use more extreme design work to accommodate a user with repetitive stress injury and this includes everything from keyboard design with variable split and tempting capability to splitting the keyboard and two distinct panels and affixing them onto a user's office chair or wheelchair Kinesis Keyboards. One-handed keyboard designs can vary from an alternative layout of traditional keys Frog Pad, to a 'chord' style keyboard were multiple keys are depressed singly or together BAT keyboard. An on-screen keyboard is a software utility that mimics the keys of the keyboard, and this is often run using some type of head mouse (explained later in this article). In many ways the Dvorak keyboard layout fits the elements of Universal Design since as a general premise it improves ease-of-use and speed of typing by putting the keys in a more human-friendly position Dvorak Keyboard info.
Specialty pointers (mice)
So many people use their mouse/pointer and don't question its ease-of-use for effectiveness. However, for many users the mouse presents substantial physical challenges. In addition to the traditional approach to the mouse with which we are all familiar there are several other approaches that may be less familiar: these include rollerball, head-worn, joystick, and visual. The general idea behind the rollerball mouse is that the user doesn't need to keep their wrist in a fixed position, possibly exacerbating RSI symptoms or presenting a physical position for their hands which are not viable. Rollerball mice come in a lot of flavors but basically all provide a floating ball that can be manipulated with the fingertips, palm of the hand, butt of the hand or other technique Kensington Expert. The general concept behind a head-worn mouse is that the user moves their head and/or something worn on the head to move the mouse on the screen; this is often coupled with a sip-and-puff system that allows the user to use their breath to perform the clicking; or with a dwell system where allowing the mouse to rest at a specific point on the screen for a user definable specified time performs the clicking function. Many people with mobility limitations find positioning their hand on a traditional mouse is very difficult and a number of companies have made a mouse based on the joystick controller concept which is both easier to manage and requires a lower level of dexterity.
In recent years a number of new approaches to pointer control have appeared, and these include using retinal movements, facial tracking, and brain waves. In addition, there are a broad range of mice specifically provided for individuals with severe mobility impairment including quadriplegia provide access using just the head or mouse Jouse.
Speech input technology
Speech Input Technology-a number of companies build speech input technologies capable of providing vocal command-and-control and speech to text functionality. The new Windows Vista operating system includes a speech input utility Windows Speech Recognition, and probably the most well-known speech input technology in North America is the Dragon NaturallySpeaking product line Dragon NaturallySpeaking.
The GUI is briefly mentioned above, and one obvious implication of using a visual system for interacting with the computer system is that people experiencing visual challenges may have increased difficulty or be prevented altogether from accessing information. Generally, individuals with vision challenges will be described as "low vision" or "blind." A low vision user generally will have some usable vision, and will use some degree of visual access for computer and print documentation. Many people who are described as low vision will also benefit from technologies that assume the user has no visual access.
Closed circuit television (CCTV)
A fixed or movable camera head (generally with autofocus) projects a magnified image of print documentation like a newspaper either on a dedicated display or integrated into a computer display Onyx CCTV line.
A software magnifier can provide variable levels of magnification as well as general display management, such as contrast schemes, and pointer schemes. These systems are often coupled with screen reading utilities. Adjunct keyboards can be used to control software functionality in addition to using standard keystroke assigned hot keys ZoomText Magnifier.
Software readers announce text or other information from the computer display in a synthesized computer voice ZoomText Reader.
Screen readers announce text or other information from the computer display in a synthesized computer voice; intended to provide a spoken level of support that provides information about every activity that has taken place on the screen. Some screen-reading software includes scripting functionality to expand "out-of-box access." The general assumption is that the user will drive functionality using the keyboard Jaws For Windows.
Refreshable Braille displays
Refreshable Braille displays connect to a computer system to provide ongoing Braille output regarding events on the computer display Humanware BrailleNote. Some displays also include spoken output KNFB Mobile.
Mobile readers are hand-held or similar portable devices that can announce information using synthesized human speech. These devices not only read printed documents like menus, but also signage, whiteboards, and other items at a distance.
The breadth of symptoms of individuals with learning disabilities can be very broad. Generally, products are provided with multiple capabilities in order to address this specific issue.
Most readers provide synthesized speech to read text, as well as supporting things like talking dictionaries and other support for improved literacy. Most LD readers also highlight the text as it is being spoken by the system so that the user can make a visual/cognitive association with the audible pronunciation of the word (often referred to as multimodal learning) WYNN Reader.
Changing color schemes can enhance one's ability to access information.A related approach is to use masking, which blocks much of the screen so that one is not visually distracted by other information currently being presented.
Word prediction helps the user by making suggestions as words are typed. Some Word prediction software is heuristic, which means that it learns patterns and habits as the user uses it WordQ.
Rather than trying to use a purely linguistic/textual approach to organizing thoughts and creating opportunities for communication, graphical organizers allow one to use a host of supported tools to process in a more visual way Inspiration Software.
As a final note, we have put digital recorders in their own category as these have a broad use across many disability categories. Most digital recorders can record both near sound and distance sound (conferences and meetings), and many come with software that allows the user to download whatever has been recorded to a computer; either for later or for processing/manipulation by speech input technology Olympus DS50.
It is also worth noting that many of the available assistive technologies, including some of the above referenced technologies, maybe available as shareware, or built-in to the operating system. Additional information about assistive technologies and their use can be found many places on the Internet and at the public library. An excellent starting point is the Microsoft Accessible Technologies Group (ATG).
About the author
Edward S. Rosenthal is President and CEO of Next Generation Technologies Inc., a Lynnwood, Washington-based technology consultancy that has been providing assistive technology consulting services since 1993. More information can be found at: Next Generation Technologies, and he may be contacted at: email@example.com.