Perkins Brailler
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The Perkins Brailler is a simple machine used to write braille. The Perkins Brailler is a "braille typewriter" with a key corresponding to each of the six dots of the braille code. By simultaneously pressing different combinations of the six keys, users can create any of the characters in the braille code. In addition to these six keys, the Perkins Brailler has a space key, a backspace key, and a line space key. Like a manual typewriter, it has two side knobs to advance paper through the machine and a carriage return lever above the keys. The rollers that hold and advance the paper have grooves designed to avoid crushing the raised dots the brailler creates.
Although braille notation was designed for visually impaired people to read, prior to the introduction of the Perkins Brailler it was relatively difficult and cumbersome for visually impaired people to write braille. Braille writers created braille characters manually using stylus and slate (as developed by Louis Braille) or by using one of the relatively complex, expensive, and fragile braillewriting machines that had been developed prior to the Perkins Brailler.
Stylus and slate are still used today and are still practical for many purposes. Users compare a stylus and slate to handwriting, while using a Perkins Brailler is more like typewriting.
The Perkins Brailler was first produced in 1951 by David Abrahams, a woodworking teacher at the Perkins School for the Blind. The director of the Perkins School for the Blind, Gabriel Farrell, asked Abrahams to create an inexpensive and reliable machine to allow students to more easily write braille. Farrell and Abrahams worked with Edward Waterhouse, who was a math teacher at Perkins, to create the design for the Brailler.
According to information from the Perkins School, the invention of the Perkins Brailler "revolutionized communication for the blind" by making it much easier for both visually impaired users and braille transcribers to write braille.[1]
The Perkins Brailler is produced by and is currently available from Howe Press. Howe Press has manufactured over 280,000 Perkins Braillers sold to individuals in over 170 countries. The Perkins Brailler that is produced today is essentially the same as the original design created by Abrahams.
For a simple device, the Perkins Brailler is astonishingly complex, containing over 500 parts. The need to position heavy paper precisely is achieved by rolling the paper onto an internal drum, unrolling it when the user presses a line-feed key, and using a clock-like escapement to move an embossing carriage over the paper. A system of six cams consisting of rods with a square cross-section transfers keystrokes to the wire-like styli contained in the carriage. Tolerances are close, and the buildup of oily dirt with normal use necessitates periodic cleaning and adjustment. Because of its complexity, a Perkins Brailler may sell for over $700 USD; cleaning and minor repair may cost over $100 USD.
[edit] Embossers
With the advent of computers, many users create braille output using a computer and a braille embosser connected to the computer. Visually impaired users can read the computer screen by using screen reading software and/or braille displays. Users of such a system can use a computer keyboard in the standard way for typing or can use a special keyboard driver that allows the six keys sdf-jkl to be used as a braille entry device similar to the Perkins Brailler.
[edit] Braille Notetakers
Many visually impaired users use electronic portable note-taking devices that allow keyboard entry in braille using the 6-key layout of the Perkins Brailler and output in synthesized speech and/or a one or two-line refreshable braille display consisting of tiny pins made of metal and plastic. (For more information and a picture, see Braille terminal.)
Notetakers include PDA features such as an address book and calculator. Because of the many moving parts and the accessibility of the refreshable braille displays to the environment, notetakers typically cost $4,000 to $8,000 USD. They are easily damaged and must be returned to their country of origin for periodic cleaning.
