Designing Effective Speech Interfaces

The Audience for Universal Design

Approximately 10 to 15 percent of the population has an impairment that affects their ability to use consumer products safely or efficiently. This equates to about 30 million people in the U.S. Some people have impairments, or disabilities, from birth, while others acquire them through accident or disease. Many people are temporarily disabled during their lifetime and at some point we all face certain disabilities related to aging. Categories of disabilities we may face include

• visual impairments
• hearing impairments
• physical impairments
• cognitive and language impairments
• speech impairments

In addition, some people suffer from seizure disorders and others face multiple disabilities.

Assistive technology is specialized technology that accommodates users with disabilities. It is often discussed as being synonymous with universal design. While they are separate fields, they are closely related and have many goals and principles in common.

Assistive technology affects a small user group and tends to be expensive to develop because its costs are shared among a small population. For example, consider a paraplegic computer user who uses a “sip and puff” device to control their computer. The user blows air through a tube to produce Morse code that allows them to control their computer. This is an example of assistive technology. A speech-enabled GUI word processor may benefit a user with a visual or physical disability such as a repetitive stress disorder, ...