In 1988 the Braille Sports Foundation (BSF), whose mission is to increase accessibility for individuals with visual impairment (VI), was looking for a way in which individuals with VI could participate in the game of darts. After approximately one year of research and development, an Audio English Mark Dart machine was created. This machine enabled individuals with VI to effectively compete in the game of darts against sighted and unsighted opponents.

Here is a link to a long story on the machine