Chorded keyboard - AbsoluteAstronomy.com

A keyset or chorded keyboard (also called a chorded keyset, chord keyboard or chording keyboard) is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord

Chord (music)

A chord in music is any harmonic set of two–three or more notes that is heard as if sounding simultaneously. These need not actually be played together: arpeggios and broken chords may for many practical and theoretical purposes be understood as chords...

" on a piano

Piano

The piano is a musical instrument played by means of a keyboard. It is one of the most popular instruments in the world. Widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment, the piano is also very popular as an aid to composing and rehearsal...

. The large number of combinations available from a small number of keys allows text or commands to be entered with one hand, leaving the other hand free. A secondary advantage is that it can be built into a device (such as a pocket-sized computer or a bicycle handlebar

Bicycle handlebar

Bicycle handlebar or often bicycle handlebars refers to the steering mechanism for bicycles; the equivalent of a steering wheel. Besides steering, handlebars also often support a portion of the rider's weight, depending on their riding position, and provide a convenient mounting place for brake...

) that is too small to contain a normal-sized keyboard.

A chorded keyboard minus the board, typically designed to be used while held in the hand, is called a keyer

Keyer

A keyer is a device for signaling by hand, by way of pressing one or more switches. Modern keyers typically have a large number of switches but not as many as a full-size keyboard; typically between four and fifty. A keyer differs from a keyboard in the sense that there is no "board"; the keys are...

. Douglas Engelbart

Douglas Engelbart

Douglas Carl Engelbart is an American inventor, and an early computer and internet pioneer. He is best known for his work on the challenges of human-computer interaction, resulting in the invention of the computer mouse, and the development of hypertext, networked computers, and precursors to GUIs...

introduced the chorded keyset as a computer interface in 1968 at what is often called "The Mother of All Demos

The Mother of All Demos

The Mother of All Demos is a name given to Douglas Engelbart's December 9, 1968, demonstration of experimental computer technologies that are now commonplace...

Principles of operation

Each key is mapped to a number and then can be mapped to a corresponding letter or command. By pressing two or more keys together the user can generate many combinations. In Engelbart's original mapping, he used five keys: 1,2,4,8,16. The keys were mapped as follows: a = 1, b = 2, c = 3, d = 4, and so on. If the user pressed keys 1 + 2 = 3 simultaneously the letter "c" appeared. Since Engelbart introduced the keyset, several different designs have been developed based on similar concepts.

As a crude example, each finger might control one key which corresponds to one bit

Bit

A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...

in a byte

Byte

The byte is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer...

, so that using seven keys and seven fingers, one could enter any character

Character (computing)

In computer and machine-based telecommunications terminology, a character is a unit of information that roughly corresponds to a grapheme, grapheme-like unit, or symbol, such as in an alphabet or syllabary in the written form of a natural language....

in the ASCII

ASCII

The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...

set—if the user could remember the binary codes. Due to the small number of keys required, chording is easily adapted from a desktop to mobile environment.

Practical devices generally use simpler chords for common characters (e.g., Baudot

Baudot code

The Baudot code, invented by Émile Baudot, is a character set predating EBCDIC and ASCII. It was the predecessor to the International Telegraph Alphabet No 2 , the teleprinter code in use until the advent of ASCII. Each character in the alphabet is represented by a series of bits, sent over a...

), or may have ways to make it easier to remember the chords (e.g., Microwriter

Microwriter

The Microwriter is a hand-held portable word-processor with a chording keyboard. It was sold in the early 1980s by Microwriter Ltd, of London, UK...

), but the same principles apply. These portable devices first became popular with the wearable computer

Wearable computer

Wearable computers are miniature electronic devices that are worn by the bearer under, with or on top of clothing. This class of wearable technology has been developed for general or special purpose information technologies and media development...

movement in the 1980s.

Douglas Engelbart

Douglas Engelbart

recently filed two new patents for mobile chorded keyset devices and TipTap.mobi has released a chorded app for the iPhone with Douglas Engelbart.

Thad Starner

Thad Starner

Thad Eugene Starner is a founder and director of the Contextual Computing Group at Georgia Tech's College of Computing, where he is an Associate Professor, and one of the pioneers of wearable computing as well as human-computer interaction, augmented environments, and pattern recognition...

from Georgia Institute of Technology and others published numerous studies showing that two handed chorded text entry was faster and yielded fewer errors than on a QWERTY keyboard. Currently stenotype machines hold the record for fastest word entry. Many stenotype users can reach 300 words per minute. However, stenographers typically train for three years before reaching professional levels of speed and accuracy.

History

The earliest known chord keyboard was part of the "five-needle" telegraph operator station, designed by Wheatstone

Charles Wheatstone

Sir Charles Wheatstone FRS , was an English scientist and inventor of many scientific breakthroughs of the Victorian era, including the English concertina, the stereoscope , and the Playfair cipher...

and Cooke

William Fothergill Cooke

Sir William Fothergill Cooke was, with Charles Wheatstone, the co-inventor of the Cooke-Wheatstone electrical telegraph, which was patented in May 1837...

in 1836, in which any two of the five needles could point left or right to indicate letters on a grid. It was designed to be used by untrained operators (who would determine which keys to press by looking at the grid), and was not used where trained telegraph operators were available.

The first widespread use of a chord keyboard was in the stenotype

Stenotype

A stenotype, stenotype machine or shorthand machine is a specialized chorded keyboard or typewriter used by stenographers for shorthand use...

machine used by court reporters, which was invented in 1868 and is still in use. But the output of the stenotype is a phonetic code that has to be transcribed later (usually by the same operator who produced the original output), rather than arbitrary text.

In 1874, the five-bit Baudot

Baudot code

telegraph code and a matching 5-key chord keyboard was designed to be used with the operator forming the codes manually. The code is optimized for speed and low wear: chords were chosen so that the most common characters used the simplest chords. But telegraph operators were already using typewriters with QWERTY keyboards to "copy" received messages, and at the time it made more sense to build a typewriter that could generate the codes automatically, rather than making them learn to use a new input device.

Braille

The Braille system is a method that is widely used by blind people to read and write, and was the first digital form of writing.Braille was devised in 1825 by Louis Braille, a blind Frenchman. Each Braille character, or cell, is made up of six dot positions, arranged in a rectangle containing two...

(a writing system for the blind) uses either 6 or 8 tactile 'points' from which all letters and numbers are formed. When Louis Braille

Louis Braille

Louis Braille was the inventor of braille, a system of reading and writing used by people who are blind or visually impaired...

invented it, it was produced with a needle holing successively all needed points in a cardboard sheet. In 1892, Frank Hall created the Hall braille writer which was like a typewriter with 6 keys, one for each dot in a braille cell. The Perkins Brailler

Perkins Brailler

The Perkins Brailler is a "braille typewriter" with a key corresponding to each of the six dots of the braille code, 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...

, first manufactured in 1951, uses a 6-key chord keyboard (plus a spacebar) to produce braille output, and has been very successful as a mass market affordable product. Braille, like Baudot, uses a number symbol and a shift symbol, which may be repeated for shift lock, to fit numbers and upper case into the 31 codes that 6 bits offer.

After World War II, with the arrival of electronics for reading chords and looking in tables of "codes", the postal sorting office

Sorting office

Sorting office or Processing and Distribution Center is any location where postal operators bring mail after collection for sorting into batches for delivery to the addressee, which may be a direct delivery or sent onwards to another regional or local sorting office, or to another postal...

s started to research chordic solutions to be able to employ people other than trained and expensive typists. In 1954, an important concept was discovered: chordic production is easier to master when the production is done at the release of the keys instead of when they are pressed.

Researchers at IBM

IBM

International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

investigated chord keyboards for both typewriters and computer data entry as early as 1959, with the idea that it might be faster than touch-typing if some chords were used to enter whole words or parts of words. One of their designs had 14 keys that were dimpled on the edges as well as the top, so one finger could press two adjacent keys for additional combinations. Their results were inconclusive, but research continued until at least 1978.

Douglas Engelbart

Douglas Engelbart

, in a famous 1968 demonstration

The Mother of All Demos

The Mother of All Demos is a name given to Douglas Engelbart's December 9, 1968, demonstration of experimental computer technologies that are now commonplace...

introduced a computer human interface that included the QWERTY keyboard, a three button mouse computer mouse

Mouse (computing)

In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons...

, and a five chord keyset. Engelbart uses the keyset with his left hand and the mouse with his right. He uses the keyset to type both text and specific commands. To type a command Engelbart presses one of the three buttons of the mouse.

Users in Engelbart's Augmentation Research Center at SRI became proficient with the mouse and keyset. In the 1970s the funding Engelbart's group received from the Advance Research Project Agency (ARPA) was cut and many key members of Engelbart's team went to work for Xerox PARC

Xerox PARC

PARC , formerly Xerox PARC, is a research and co-development company in Palo Alto, California, with a distinguished reputation for its contributions to information technology and hardware systems....

where they continued to experiment with the mouse and keyset. Keychord sets were used at Xerox PARC in the early 1980s, along with mice, GUIs, on the Xerox Star and Alto workstations. A one button version of the mouse was incorporated into the Apple Macintosh but Steve Jobs decided against incorporating the chorded keyset.

In the early 1980s, Philips

Philips

Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....

Research labs at Redhill, Surrey

Redhill, Surrey

Redhill is a town in the borough of Reigate and Banstead, Surrey, England and is part of the London commuter belt. Redhill and the adjacent town of Reigate form a single urban area.-History:...

did a brief study into small, cheap keyboards for entering text on a telephone. One solution made use of a grid of hexagonal keys with symbols inscribed into dimples in the keys that were either in the center of a key, across the boundary of two keys, or at the joining of three keys. Pressing down on one of the dimples would cause either one, two or three of the hexagonal buttons to be depressed at the same time, forming a chord that would be unique to that symbol. With this arrangement, a nine button keyboard with three rows of three hexagonal buttons could be fitted onto a telephone and could produce up to 33 different symbols. By choosing widely separated keys, one could employ one dimple as a 'shift' key to allow both letters and numbers to be produced. With eleven keys in a 3/4/4 arrangement, 43 symbols could be arranged allowing for lowercase text, numbers and a modest number of punctuation symbols to be represented along with a 'shift' function for accessing uppercase letters. Whilst this had the advantage of being usable by untrained users via 'hunt and peck' typing and requiring one less key switch than a conventional 12 button keypad, it had the disadvantage that some symbols required three times as much force to depress them as others which made it hard to achieve any speed with the device. That solution is still alive and proposed by Fastap and Unitap among others, and a commercial phone has been produced and promoted in Canada during 2006.

Standards

Historically, the baudot

Baudot code

and braille

Braille

keyboards were standardized to some extent, but they are unable to replicate the full character set of a modern keyboard. Braille comes closest, as it has been extended to eight bits.

The only proposed modern standard, GKOS (or Global Keyboard Open Standard) can support most characters and functions found on a computer keyboard but has had little commercial development. There is, however, a GKOS keyboard application available for iPhone since May 8, 2010, for Android since October 3, 2010 and for MeeGo Harmattan since October 27, 2011.

Open-source designs

Three open-source keyer/keyset designs are available: The pickey a ps/2 device based on the PIC microcontroller

PIC microcontroller

PIC is a family of Harvard architecture microcontrollers made by Microchip Technology, derived from the PIC1650 originally developed by General Instrument's Microelectronics Division...

, the spiffchorder a USB device based on the Atmel AVR

Atmel AVR

The AVR is a modified Harvard architecture 8-bit RISC single chip microcontroller which was developed by Atmel in 1996. The AVR was one of the first microcontroller families to use on-chip flash memory for program storage, as opposed to one-time programmable ROM, EPROM, or EEPROM used by other...

family of microcontrollers, and the GKOS keypad driver for Linux as well as the Gkos library for the Atmel/Arduino

Arduino

Arduino is an open-source single-board microcontroller, descendant of the open-source Wiring platform, designed to make the process of using electronics in multidisciplinary projects more accessible. The hardware consists of a simple open hardware design for the Arduino board with an Atmel AVR...

open source board.

Joy2chord is a Chorded Keyboard driver for Linux computers. With a configuration file, any joystick or gamepad can be turned into a chorded keyboard. This design philosophy was decided on to lower the cost of building devices, and in turn lower the entry barrier to becoming familiar with chorded keyboards. Macro keys, and multiple modes are also easily implemented with a user space driver.

Commercial devices

A minimal chordic keyboard is the half qwerty where, to produce the letters of the missing half, the user presses simultaneously the space bar. It has been academically proven by Mathias and Alii that people who can touch type can quickly recover 50 to 70% of their two hands operation. The loss is a solid contribution to the speed discussion above. It is implemented on two popular mobile phones, each provided with software disambiguation, which allows users to avoid using the space-bar.

"Multiambic" keyers

Keyer

for use with wearable computers were invented in Canada in the 1970s. Multiambic keyers are similar to chording keyboards but without the board, in that the keys are grouped in a cluster for being handheld, rather than for sitting on a flat surface.

Chording keyboards are also used as portable but two handed input devices for the visually impaired (either combined with a refreshable braille display

Refreshable Braille display

A refreshable Braille display or Braille terminal is an electro-mechanical device for displaying Braille characters, usually by means of raising dots through holes in a flat surface. Blind computer users, who cannot use a normal computer monitor, use it to read text output...

or vocal synthesis). Such keyboards use a minimum of seven keys, where each key corresponds to an individual braille

Braille

point, except one key which is used as a spacebar. In some applications, the spacebar is used to produce additional chords which enable the user to issue editing commands, such as moving the cursor

Cursor (computers)

In computing, a cursor is an indicator used to show the position on a computer monitor or other display device that will respond to input from a text input or pointing device. The flashing text cursor may be referred to as a caret in some cases...

, or deleting words. Note that the number of points used in braille computing is not 6, but 8, as this allows the user, among other things, to distinguish between small and capital letters, as well as identify the position of the cursor. As a result, most newer chorded keyboards for braille input include at least nine keys.

Touch screen chordic keyboards are available to smartphone

Smartphone

A smartphone is a high-end mobile phone built on a mobile computing platform, with more advanced computing ability and connectivity than a contemporary feature phone. The first smartphones were devices that mainly combined the functions of a personal digital assistant and a mobile phone or camera...

users as an optional way of entering text. As the number of keys is low the button areas can be made bigger and easier to hit on the small screen. The most common letters do not necessarily require chording as is the case with the GKOS keyboard optimised layouts (Android app) where twelve most frequent characters only require single keys.

Historical

The WriteHander a 12-key chord keyboard from NewO Company, appeared in 1978 issues of ROM Magazine, an early microcomputer applications magazine.

Another early commercial models was the six-button Microwriter

Microwriter

The Microwriter is a hand-held portable word-processor with a chording keyboard. It was sold in the early 1980s by Microwriter Ltd, of London, UK...

, designed by Cy Endfield

Cy Endfield

Cyril Raker Endfield was an American screenwriter, film director, theatre director, author, magician and inventor, based in Britain from 1953.- Biography :...

and Chris Rainey, and first sold in 1980. Microwriting is the system of chord keying and is based on a set of mnemonics. It was designed only for right-handed use.

The BAT

BAT keyboard

A BAT keyboard is a one-handed keyboard consisting of a base, on which the hand rests, and seven keys. Through pressing combinations of keys, one can attain the same functions as a regular keyboard....

is a 7-key hand-sized device from Infogrip, and has been sold since 1985. It provides one key for each finger and three for the thumb. It is proposed for the hand which does not hold the mouse, in an exact continuation of Engelbart's vision.

Modern

Modern examples of chorded keyboards include TipTapSpeech (using Engelbart's original mapping), the GKOS keyboard, the FrogPad, the In10did method, the EkaPad, TextFaster and HotTyper. Some of them are intended for tiny tablet computer

Tablet computer

A tablet computer, or simply tablet, is a complete mobile computer, larger than a mobile phone or personal digital assistant, integrated into a flat touch screen and primarily operated by touching the screen...

s and wireless mobile terminals, many of them are additionally available as apps on Apples iOS devices.

Chris Rainey

Chris Rainey

Chris Rainey is an American football running back. He currently attends the University of Florida in his senior year.-External links:* *...

, the co-inventor of Microwriter

Microwriter

The Microwriter is a hand-held portable word-processor with a chording keyboard. It was sold in the early 1980s by Microwriter Ltd, of London, UK...

, re-introduced Microwriting for PC and Palm PDAs with a standalone miniature chording keyboard called CyKey

CyKey

Chris Rainey re-introduced Microwriting for PC and Palm PDAs with a standalone miniature chording keyboard called CyKey, after co-inventing the Microwriter in the 1980s. The CyKey caters to both left and right-handed users, being 9-keys...

which caters to both left and right-handed users, being 9-keys. CyKey

CyKey

is named after the Microwriter

Microwriter

The Microwriter is a hand-held portable word-processor with a chording keyboard. It was sold in the early 1980s by Microwriter Ltd, of London, UK...

chord system's co-inventor Cy Endfield

Cy Endfield

Cyril Raker Endfield was an American screenwriter, film director, theatre director, author, magician and inventor, based in Britain from 1953.- Biography :...

, who died in 1995 but the name also reflects its intuitive nature.

The GKOS is a 6-key keyboard with a different signs and commands allocation of the 63 different chords in order to provide all PC keyboard functions and to make entering letters and numbers lighter by having to press fewer keys simultaneously. The 6 physical keys are intended to be on the back of the device and to be operated with the six free fingers of two hands holding the device. Another option is to have virtual GKOS keys positioned towards the sides of a touch sensitive screen. This so called GKOS Thumbs has additional keys to enable all combos by only one keypress per hand. GKOS iPhone, Android phone/tablet and MeeGo Harmattan applications use this principle.

The EkaPad is a 12-key chorded keyboard operated with the four fingers of one hand. It is supported on the thumb. With the 9 main keys, (operated by the index, middle, and ring fingers), 2 prefix keys and one delete key, the EkaPad can produce all the inputs of a standard qwerty keyboard with one, two, and a few three finger chords. For some characters one or two prefix chords are required. 9 main keys (3x3 matrix) can produce a total of 511 chords. With each of the three fingers limited to its own row, 229 chords are possible with 3 fingers. EkaPad uses 66 of these accessible chords. One and two finger chords produce about 85% of American English; with an additional prefix chord about 97%. In addition, the EkaPad can store 100 text strings and 100 keyboard shortcuts. Like many other chorded keyboards, this keyboard can be used with one hand.

The FrogPad is a 20-key chorded keyboard about the size of a numeric keypad that can be used with one hand, and is optimized by character frequency. 85% of average keystrokes in English text can by typed without chording, and chords are limited to 2 fingers.

The In10did method is a ten-key limited chord system that places one key under each finger in order to utilize all of them, however only two are needed for any operations (excluding the "F" keys, which require three key presses). Each key is essentially a shift key so that with ten keys, there are ten single strokes and ninety two-finger keystrokes. The alphabet is produced with a single press or by shifting with a thumb. Changing modes, such as number lock, can make other input provided with a single keystroke. This avoids complex chords while providing enough keystrokes for efficient typing and allows for some unique implementations such as typing with gloves. One other interesting application is on a video game controller and called the X-SKIN which is expected to be commercially available by 2010 and could help make popular MMORPGs possible on console systems. The system can also be applied in a single hand configuration or as one key at a time if needed. Claimed advantages of the IN10DID method are the diversity of devices, limited motion and simple chords.

The Twiddler is a 16-key keyboard (plus mouse) keyboard designed to be held and operated in one hand. It was originally introduced in the early 1990s and is currently being produced by TekGear. It was popular among wearable computer

Wearable computer

researchers and hobbyists.

Principles of operation

History

Standards

Open-source designs

Commercial devices

Historical

Modern

See also