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Vol. 5, No. 2 March/April 1997 |
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Mouse Alternatives For Everyone
by Ed Salisbury
The X-Y Position Indicator was designed by a man named Douglas Englebart in 1964 for use with advanced office automation systems. This now commonplace device is used by almost every Windows user, Macintosh user, and Internet surfer. Its newer name, the mouse, describes more its appearance than its function. With the proliferation of the mouse, there has also been an increase in the number of people unable to use the computer effectively due to an inability to operate the standard mouse. Fortunately, for every style of mouse, there are at least two alternative devices that can take its place. Many of these mouse alternatives, or mouse emulation devices, are not specifically designed for people with disabilities. In other words, they are, by nature of their design, suitable for everyone.
There are two main disadvantages to the standard mouse, especially for people with disabilities. One disadvantage is the amount of wrist and arm movement needed to guide the mouse to the far corners of the mouse pad. The second disadvantage is the large amount of room needed on a desktop for the operation of the mouse. To help solve the first problem, most mouse drivers include an adjustment for acceleration. Setting a high value for acceleration requires only a small amount of mouse movement to move the mouse pointer a large distance. As a person’s mouse skills increase, the acceleration can also be increased. Conversely, a person with mild tremors or spastic movements would probably benefit from the mouse acceleration set to low. Many people do not realize that there is a simple form of mouse emulation included with most computers. Both the Macintosh (system 7.0 or later) and Windows 95 computers include a MouseKeys feature. When the computer is set in this mode, the numeric keypad can be used to move the mouse cursor. All mouse functions including button click and click and drag can be achieved using this set of keyboard keys. For those using DOS, a free program called Access DOS can be obtained from the Trace R&D Center in Madison, Wisconsin. Windows 3.0 or 3.1 users need only contact Microsoft by phone, or visit their site on the Internet, to receive the free Access Pack for Windows.
Two products, the track ball and the track pad, are designed to solve both the space and mobility problems of the standard mouse. The track ball sits stationary on the desktop. The computer user need only turn a ball on the top of the device to move the mouse pointer. This ball can generally be turned using a single finger, thus eliminating the need for upper arm movement. Track balls come in many shapes and sizes and, depending on size, can take up very little room on the desktop. Like the track ball, the track pad also sits stationary on the desktop. It is operated simply by passing one’s finger over a small, touch sensitive tablet. Because the trackpad has a sealed surface and no moving parts, it is generally less susceptible to problems caused by oil and dirt buildup. Both track balls and track pads are commonly built into laptop computers but may be purchased for desktop computers as well.
Many people who use power wheelchairs prefer to use a joystick rather than a mouse. Joysticks can be purchased for use with the computer that closely resemble those used with a power wheelchair. It is important to choose one that acts as a mouse, not as a standard game joystick. Joysticks that plug into the keyboard port (PS\2 and ADB) are mouse emulating. Ones that plug into the game port of a sound card are generally specialized and can only be used with certain games.
Another common mouse alternative is the touch sensitive display. This type of access is commonly found in kiosks where a natural, self-explanatory interface is required. The visitor to the kiosk need only touch desired selections on the computer screen. This technology can also be applied to a range of software on the personal computer. Children may benefit from the touch sensitive display because it utilizes pointing, a natural gesture that emerges relatively early. The cognitive ability and the fine motor control needed to use the mouse generally comes later in the child’s development. Touch screen access is especially suited for early education software. Software requiring very precise mouse movement is often difficult to access with touch sensitive displays.
This form of mouse emulation can be achieved in three ways. The first method is to purchase a touch sensitive monitor. Although somewhat expensive, they do provide a high level of accuracy and durability. For those who do not wish to purchase an additional monitor, or for those who use a laptop computer, another option is available. Several companies can embed a touch sensitive membrane into or onto the existing monitor. The third and most common option is to purchase a touch sensitive screen that attaches to the surface of the monitor. Because these screens generally stand away from the actual display a slight distance, they often need recalibration when more than one person is using the computer.
For a person with no functional hand use, several mouse alternatives are available. For those who have reliable head movement, the HeadMouse and HeadMaster may be effective means of mouse emulation. A person using the HeadMouse need only wear a small reflective dot on the forehead. HeadMouse uses infrared technology to move the mouse pointer in correspondence with the person’s head movement. A person using the HeadMaster wears a lightweight headset attached to the rear of the unit via telephone cable. Using ultrasonic technology, the HeadMaster controls the mouse pointer in a way similar to that of the HeadMouse. A mouse click with either device can be achieved using a remote infrared switch or any standard ability switch. The No Hands Mouse is another mouse alternative ideal for a people with little or no use of their hands. The No Hands Mouse utilizes two foot pedals. One pedal is used to move the mouse pointer, while the other pedal acts as the mouse button.
All mouse alternatives can be coupled with an on-screen virtual keyboard for text entry. Some virtual keyboards include a dwell feature which eliminates the need to click the mouse to select a key. This is especially beneficial when using the HeadMouse or the HeadMaster, allowing total hands free access to the mouse and keyboard.
Ideally, to make the graphical user interface of Windows and Macintosh more accessible to people with visual impairments, the mouse needs to be eliminated completely. Computers using Windows as their operating system can be accessed almost completely with keyboard hot keys instead of the mouse. Unfortunately, the Macintosh requires the addition of third party software to make this happen. Many screen eview programs that provide speech output for people who are blind include features that allow access to all windows and icons using just the keyboard.
Listed above is only a small sampling of mouse alternatives that are available. Many of these can be purchased in local computer stores. Others are available through disability related catalogs. Ideally, a form of access should be designed in a way that benefits everyone. Your local ATRC has a variety of mouse alternatives available for loan. If you would like additional information on any of the mouse alternatives, including specific brands and prices, call your local ATRC.
