US 5,267,181 AGrant
Cybernetic Interface for a Computer That Uses a Hand Held Chord Keyboard
Issue Date:1993-11-30
•71 Claims
•7 Drawing Sheets
Abstract
The cybernetic interface of the present invention contemplates a remote hand-held, data input unit which communicates as an input device to a computer. The data input unit has the following broad features; an ergonomically correct handle, a symmetrical design so that the handle may be operated by either the right or left hand of the user, a chord keyboard on the handle that is operated by the four fingers of a hand of a user, a shift keyboard that is operated by the thumb of the same hand of the user, an integral means for generating pointer control information, a strap or band to support the unit in the hand, and a communications means to communicate the input from the data input unit to the computer either by wired or wireless means.
Metadata
Assignee
- Handykey Corporation
Inventor
- Christopher S. George
Application Information
Application Number:US 4316118
Filing Date:1989-11-03
Priority Date:1989-11-03
Art Unit:236
Classifications
IPC:
G06F 302
Field of Search:
364709.15;709.12;708;705.03
Patent Drawings (7 sheets)
Description
Background of the Invention
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
The present invention relates generally to devices for entering data into a computer.
The most common way for a person to interact with a computer is through a keyboard. The standard computer keyboard is the QWERTY keyboard, first developed in the 19th century for use with mechanical typewriters. The QWERTY keyboard, sometimes known by its full name of QWERTYUIOP, has keys spread out in horizontal rows across the surface of the keyboard. Imprinting a character is achieved by depressing the corresponding key on the keyboard.
The QWERTY keyboard was designed to provide the maximum physical separation between the most frequently used letters of the alphabet, and thus reduce the likelihood of keys jamming during typing. The layout of keys that resulted is not particularly logical; the name of the keyboard is taken from the ordering of the first row of keys.
An alternate type of QWERTY keyboard is the Dvorak keyboard. The Dvorak keyboard has the most frequently used keys placed where they are most accessible to the typist. This arrangement is well known for allowing typists to attain greater efficiency and faster typing speeds relative to the old QWERTY keyboard.
The QWERTY keyboard, nevertheless, remains the standard keyboard despite the greater efficiencies of the Dvorak keyboard. One impediment to adopting the Dvorak keyboard is its similarity with the QWERTY keyboard; a typist who is skilled at typing on either a QWERTY or a Dvorak keyboard can type only with difficulty on the other. This problem of incompatibility appears to happen because both the Dvorak and QWERTY keyboards are mere variations of the same basic keyboard. It follows that the same motor centers of the brain needed to type on a QWERTY keyboard are also needed to type on a Dvorak keyboard. The finger motions needed to type on either keyboard are similar. This similarity causes the human mind to have trouble keeping the motor control needed to type on either one of the keyboards separate. Using both keyboards skillfully requires too much of a typist because the typing skills interfere. It is common knowledge that a typist can transfer between the QWERTY and Dvorak keyboards only with great difficulty.
The skill required to type on both the QWERTY and Dvorak keyboards is difficult to learn and easy to forget. A person must practice for hundreds of hours to become proficient in typing on either the Dvorak or QWERTY keyboard. These difficulties result from the extreme complexity of motion required to type efficiently; the typist must learn and retain the trajectory between each key and every other key on the keyboard covered by a given finger. This rote learning is quickly forgotten if not practiced regularly.
Special characters compound the complexity of typing on a QWERTY or Dvorak keyboard. A typist often must type characters other than alphanumeric characters--mathematical, cyrillic, and oriental symbols and characters are common examples. Customizing a conventional keyboard to accommodate these additional symbols is easy to do using additional shift keys such as the "control" and "alternate" keys. These additional shift keys, however, create whole new levels of complexity for typing. A typist must learn how to move efficiently between the keys having these new characters. As a result, learning these new keystrokes is as complex as learning how to type the alphanumeric characters. Moreover, there is no standard by which to add these additional characters to a computer keyboard. Each computer maker and, indeed, every software maker can assign different characters to the "alternate" and "control" shift keys. The conventional keyboard thus reduces even a skilled typist to using a "hunt and peck" method of data entry as a mattter of necessity--the number of times that special characters need to be typed do not permit anyone to learn and retain the knowledge needed to type them efficiently.
Another disadvantage associated with the conventional, QWERTY-type keyboard is the increase in the number of inexperienced typists who are using keyboards as a result of office automation. The proliferation of personal computers, hand calculators and other forms of automated office equipment have required that virtually everyone enter data into a computer through a keyboard. However, very few individuals have the time to become proficient typists. Hence, most typing involves the "hunt and peck" and "hunt and check" methods, defined herein as selecting one key at a time based on some template overlay. This form of data entry is inefficient and frustrates the ability of office automation to increase productivity.
Yet another liability of the conventional QWERTY-type keyboard is its size. The conventional keyboard requires a certain minimum surface area in which to spread out the keys since each key must have a certain minimum size to be touched.
The size of the QWERTY keyboard is now a concern. The minimum size of a computer has been decreasing for some time. One limit that was reached in the personal computer was the size required for a video display tube (VDT)--the last vacuum tube commonly used in consumer electronics. Recent advances in solid state displays, however, eliminate the necessity of using a VDT for the display screen. Microprocessor and microelectronic technology, together with solid state video display technology, allow computers that are quite small to be produced--a personal computer can fit in a package no larger than a small book, rather than the several cubic feet that is now so common. It is the keyboard--that anachronism from the 19th century--that now sets the lower limit of the practical size of a personal computer.
There is another type of keyboard for entering data into a computer--the chord keyboard. In contrast to the QWERTY and Dvorak keyboards, the chord keyboard does not require a typist to memorize a large number of finger trajectories to enter data. The chord keyboard has a small number of keys, usually between five and twenty-five. In addition to generating characters by pressing a single key, a chord keyboard also generates a character when two or more keys are simultaneously depressed--in contrast to the conventional, QWERTY-type keyboard which was specifically designed to avoid a typist depressing multiple keys at the same time.
Chord keyboards have many desirable attributes that are well known in the art. For example, a typist can learn to "touch type" on a chord keyboard with 30-60 hours of practice. One reason for this shorter learning period is that the relatively small number of keys on a chord keyboard reduces the errors caused by fingers getting out of alignment the way they easily can on a QWERTY keyboard. Writing is something done by one hand; a chord keyboard also can be operated by one hand. Typing on a chord keyboard therefore can be more natural than typing on a conventional, QWERTY-type keyboard. There is no need for the typist to memorize many complex finger trajectories in order to use a chord keyboard.
Another known advantage of a chord keyboard is its compatibility with the QWERTY and Dvorak keyboards. The type of motor control needed to type on a chord keyboard compared to that needed to type on a conventional, QWERTY-type keyboard is such that a typist apparently experiences little or no difficulty in changing back and forth between them. It should therefore be possible for the chord keyboard to coexist with the QWERTY keyboard.
The chord keyboard has another attribute that makes it particularly important now--chord keyboards are smaller in size. The layout for 5-25 keys requires substantially less surface area than that needed to layout the 30-100+ keys found on typewriters, personal computers and word processors. Moreover, customizing a chord keyboard involves the relatively simple process of assigning new characters to previously unused combinations of keys or adding additional shift keys. Learning to touch type these new key arrangements is also less time consuming than on a conventional QWERTY-type keyboard. The chord keyboard has great promise for reducing the size of the lap top computer and for increasing productivity and typing speed.
There are problems, however, in realizing the promise of the chord keyboard. The art contains many examples of chord keyboards, but none have succeeded in unlocking the enormous potential inherent in the basic concept of the chord keyboard.
One disadvantage of the chord keyboard is that a typist must be assisted to find the keys on the keyboard. A chord keyboard can leave the typist without any way to know which combination of keys will generate a particular character. In contrast, the QWERTY keyboard displays all the characters all the time; the typist is invited to find characters and to press the character keys on the keyboard. A chord keyboard is to a conventional, QWERTY keyboard as a command driven software program is to a menu driven program; a command driven program does not tell the user which commands are available, whereas a menu driven program does by displaying commands on a menu. The chord keyboard hides its characters, whereas a QWERTY keyboard always has them in full display. Hence, the QWERTY keyboard is more "user friendly" even though it is more difficult to use.
Another disadvantage of a chord keyboard is the extra work needed to generate each character. A conventional, QWERTY-type keyboard requires only one finger motion to generate a character. A chord keyboard, by definition, requires depressing several keys for at least some characters. This additional work can become tiring.
Another disadvantage of the chord keyboard is that it does not have an ergonomic design. Indeed, chord keyboard designs appear to have been made without ever considering the stress that they place on the typist. Previous chord keyboards can require the typist to engage in hand motions that are highly abnormal such as, for example, keeping the hand pressed flat against the keyboard or requiring the typist to generate a character by lifting the finger rather than by depressing it. The human hand is adapted to grabbing and pulling objects--not repeatedly moving fingers up and down across a flat keyboard surface or repeated flicking buttons to generate characters. The lack of an ergonomically correct design for a chord keyboard limits its acceptance and its utility.
A disadvantage shared by the conventional, QWERTY keyboard and previous chord keyboards is a matter of health called repetitive stress injury (RSI), a malady that has been traced directly to doing repetitive work in a way that the human body is not designed to do. RSI is a multi-faceted problem, but some of its elements related to using keyboards involve sitting at a console bound--or desk bound--keyboard with a relatively fixed position of the back, neck, arms, and fingers, for extended periods of time. The cure for RSI is to redesign the work to be more natural for the worker, i.e., to make the equipment more ergonomic so that the repeated activity does not stress the body. Chord keyboards in the prior art, had they been more utilized, would have been particularly prone to inflicting RSI on the typist due to the larger number of keystrokes required to enter the same data.
Another disadvantage shared by both the QWERTY keyboard and the chord keyboard is that neither have been integrated into the general cybernetic interface required for man-machine interaction. For example, a personal computer typically includes a separate mouse or other device to move the pointer on the display. The objective is to point at "icons" on the display which are then selected using a separate "click on" button. The "click and drag" feature used on the Apple Macintosh, Macintosh II and IBM PS2 personal computers make heavy use of the pointing device which are required by the graphical user interface. Neither machine, however, is equipped with a keyboard with an all purpose user control. As a result, a typist must inefficiently shift back and forth between the keyboard and the pointing device.
The disadvantages associated with the chord keyboard have prevented its acceptance where most needed--the commercial marketplace. Now, however, those disadvantages must be overcome so that personal computers can become fully portable. There is thus an urgent need in the art for a small, portable chord keyboard that is ergonomically designed to counter repetition stress injury as well as minimize the time needed to learn new keystrokes. It is further advantageous that the chord keyboard provide all the data input required by the computer in an ergonomically correct manner. Only then can the potential of the chord keyboard be realized in commercial practice.
The ergonomic disadvantages of prior chord keyboards may be summarized as:
1) Too few keys, resulting in too many fingers being used to generate each desired character; chord keyboard typing was therefore very tiring.
2) Too many finger press positions, requiring very fine motor control; errors were easily made.
3) No logical arrangement of characters so that chord typing was difficult to learn.
4) No visual cues indicating what keys to press to generate a given character.
5) Unnatural finger positions were required to type each character.
Summary of the Invention
The present invention generally relates to a cybernetic interface for a computer that uses a remotely held chord keyboard to input data to a computer. The objective of the present invention is to enable the chord keyboard to be used as a small, ergonomically correct, completely portable manual data input unit, and to provide a completely portable cybernetic interface that allows a user to input data into the computer. The present invention facilitates entry of all types of information that a user needs to enter to interact with a computer in one, hand-held, transportable unit. Moreover, the interface is designed to facilitate rapid, repeated data entry by even inexperienced typists.
The cybernetic interface of the present invention contemplates a hand-held, manually operated data input unit coupled by a communications link to a computer, and preferably a display. The data input unit has the following broad features; an ergonomically correct handle, a symmetrical design for use by either the right or left hand of the user, a chord keyboard or keypad on the handle that is operated by the four fingers of the hand of the typist, a shift keyboard or keypad that is operated by the thumb of the same hand, an integral pointer positioning unit, and a strap or band that fits around the back of the hand that holds the unit in the palm without effort.
Generally, the data input unit of the interface uses a microprocessor to generate input data, specifically scan codes, sensor data and control codes. The communications link transmits this input data from the data input unit to the computer and the latter uses a look-up routine to assign characters to this data based upon the scan codes and/or other data. The display, when used, displays the symbols which correspond to the assigned characters. The communications link, computer and display, if used, may be contained in the data input unit so as to provide a completely integrated system. Alternately, the communications link and computer may be contained within the data input unit and the display kept separate from that unit but connected to it by a cable or other suitable transmission means.
In the case where the computer is separate from the data input unit, i.e., the basic configuration, the communications link may be a cable connected to the data input unit at one end and the input port of the computer at the other end. The communications link may also be a wireless link consisting of a modulator, transmitter, receiver and demodulator. In this configuration, the modulator and transmitter are located in the data input unit, and the receiver and demodulator comprise part of a separate base unit connected by a cable to an input port of the computer. If the computer is contained within the data input unit, the preferable communications link is a cable.
It should be noted that the data input unit uses a microprocessor to scan the chord keyboard and generate the scan codes. The computer interprets these scan codes received from the data input unit using a software look-up routine.
In a wireless communications link embodiment, the data input unit includes a communications unit to transmit the input data from the keyboard to the base unit. The base unit of a wireless embodiment receives the data from the data input unit and directs the input data from that unit to an input port of the computer.
The ergonomic design of the chord keyboard of the present invention features a handle which can be held in one hand and uses finger motions to generate characters which are the same as the finger motions required to clench a fist. The motion is entirely natural, and therefore should cause no stress to the typist as well as reduce the effort needed to type. The thumb can press a variety of shift keys on the top of the keyboard. The other fingers can press keys on the front face of the handle. A hand strap is attached to the data input unit to keep the keyboard mounted in the palm of the hand so that the typist does not have to exert any effort to hold on to it--while typing, thinking, talking or at any other time. Furthermore, the hand can relax completely when not entering data since the typist need exert no effort to hold the keyboard in the hand. Because it is geometrically symmetrical in the preferred embodiment, the handle is ambidextrous and the typist can easily switch the handle to the other hand when the first hand becomes tired.
In the present invention, the keyboard is preferably arranged on an ergonomically designed handle in three columns of four rows each, where keys can be operated by the four fingers of the typist. The keys are preferably arranged in a logical pattern that is easy to learn and to remember. For example, the keys "ABCD" and "EFGH" can be positioned along the right and middle columns and the keys "space", "backspace", "delete", and "enter" along the left column, respectively. The remaining common keys can be chorded with one of the three keys on the upper row under the first finger. This type of keyboard arrangement creates a simple way to remember the location of the most common keys and thus reduces the need for using the "hunt-and-peck" typing method. Also, with twelve finger keys, the most frequently used characters have only one or two keys involved.
A color coded template can overlay the keys to facilitate even easier identification. The present invention also contemplates a help menu that would display the character chords on the display screen of the computer. These features provide the chord keyboard of the present invention with the advantages of easier character identification usually found only in a conventional, QWERTY-type keyboard.
The shift keys can be positioned on the top of the keyboard for actuation by the thumb. The top of the keyboard can also include indicators such as a display to show, for example, characters transmitted from the computer, when the keyboard is operating and when the battery is low. The shift keys are arranged so that the thumb can depress more than one key at a time, if desired, and only if that is desired.
One embodiment of the invention contemplates controlling the pointer with a tilt sensor embedded inside the keyboard. The tilt sensor can be an electrolytic tilt sensor such as Model SP5000 manufactured by the Spectron Corporation of Hauppauge, N.Y. This dual axis device responds to the angle of inclination of the keyboard in two axes and as interpreted by the computer, such that the pointer on the screen is moved up, down, left and right by pressing the "mouse" button with the thumb and tipping the keyboard backward, forward, counter-clockwise and clockwise, respectively. The amount of movement of the pointer on the screen is proportional to the arc through which the device is moved. The electrical resistance among electrodes in the sensor changes with the angle from vertical as an electrolytic fluid moves in the sensor. These changes are read through an analog to digital converter by a microprocessor and sent to the computer which interprets these changes as pointer movements on the screen. The typist can press finger keys simultaneously with the "mouse" button to generate "mouse click", etc. commands. Alternately, a pair of angular accelerometers, two pairs of translational motion accelerometers, or a conventional rolling ball type sensor can be used in place of the tilt sensor to provide pointing information.
The commands generated by the keyboard, the shift keys and the integral pointer positioning unit can be communicated to the CPU of the computer through the communications unit. For example, the input data can be classified as a scan code of three bytes in response to the release of a key, as a control code of one byte in response to releasing the "mouse" key and as pointer position information of six bytes to indicate the desired pointer movement on the screen. The scan code indicates which keys in the data input unit have been pressed and released. The control code can instruct the CPU when to repeat a given character, although other types of information are possible. The tilt sensor can provide data that is interpreted by the CPU as pointer movement. The pointer motion can be constant in any given direction, although the motion can be made to accelerate either in response to the rapidity of movement of the data input unit (dynamic tracking) or by pressing additional finger keys. The tilt values are averaged over a given period of time to reduce the effect of slosh. A look up routine in the computer assigns ASCII character values and special functions such as "caps lock", "number lock", etc. to the three byte scan codes.
The communications unit can transmit the information over a cable or wire directly to an input port of the CPU or remotely using an appropriate remote wireless communications link, such as a radio frequency transmitter or any other acceptable type of communications link such as infrared and ultrasonic transmitters, many examples of which are well known.
The base unit receives the communications from the communications unit and provides the input port of the CPU of the computer with the appropriate data. The base unit can merely relay the codes received from the data input unit or it can execute its own look up routine to assign different codes to those received from the data input unit. It is contemplated that the base unit could appear to the CPU to be identical to the keyboard and mouse normally found at the user input. While not described specifically herein, the computer may also communicate information to the data input unit which would then be shown on an optional integral display on the data input unit. The base unit may also receive input data from more than one unit. For example, two handed typing using two data input units is consistent with the teachings of the present invention. In the wired embodiment, a separate base unit for each data input is not needed since the wire can connect the unit directly to one of several available computer ports.
The present invention is foreseen as having particular utility for portable, "lap top" personal computers. These computers are expected to benefit the most from the smaller keyboard obtainable using the present invention because the minimum size of the computer is no longer limited by the keyboard--the present invention is designed to fit comfortably into one hand, and have the functionality of a full keyboard and mouse.
The present invention should also be advantageous for typists using other types of computers. Learning new key strokes should be easier and more rapid, especially for special symbols, different alphabets, customized keyboards and the like. With the integral pointing device of the invention, there is no longer the need to continuously switch back and forth from mouse to keyboard. Indeed, the character look up routine used by the computer facilitates easy customization of the present invention. Using a remote transmitter should allow a typist to compose a document while pacing around the room. With an effective addressing range of the chord keyboard of over 4,000 keys (through combinations), unused combinations can be assigned to many different things such as telephone control, TV and stereo remote control, word and phrase generation, music playing through a MIDI interface, and general remote control operation.
The present invention is advantageous for handicapped individuals, for example, those having the use of only one hand. The present invention also has particular advantage for the voice impaired. The present invention provides for forming over 4,000 key combinations which may correspond to entire words or phrases which could, for example, be supplied to a speech synthesizer or similar communication device. The reduced stress afforded by the ergonomically correct construction of the keyboard should greatly relieve the stress associated with communication for these individuals.
The present invention also provides an advantage for typing in languages having large character sets such as Chinese or Japanese; the relatively simple interface of the present invention, augmented as needed primarily with additional shift keys, can generate a large number of characters. Indeed, the present invention provides a way to enter character data from virtually every language using the same physical keyboard.
The present invention also mitigates RSI in several ways. The user is not required to sit in a fixed position; even using a cable as the communications link, the typist can move about freely while still being able to continue to enter data up to the limit established by the wire. The data input unit is also symmetrical and may be freely used by either hand; thus, the other hand may be used when the first hand tires. The hand can relax completely when not actually entering data. A strap around the back of the hand holds it comfortably in place so that the typist need exert no effort to grip the device.
The hand held, ergonomically correct cybernetic interface of the present invention should make a contribution to the general ability of users to control machines in ways that cannot yet be foreseen. Perhaps the most significant contribution foreseen for the present invention is to overcome the disadvantages of the chord keyboards of the prior art and finally turn the nascent promise of such keyboards into practical reality.
Brief Description of the Drawings
FIG. 1 is a front perspective view of the hand held, data input unit of the present invention, showing the chord keyboard and hand strap according to the present invention;
FIG. 2 is a rear perspective view of the data input unit, including the keyboard, shown in FIG. 1;
FIG. 3 is a bottom perspective view of the data input unit;
FIG. 4 is another perspective view of the data input unit showing how the unit is grasped during operation of the chord keyboard;
FIG. 5 is a plan view of the data input unit illustrating an exemplary key layout for the chord keyboard of the present invention;
FIG. 6 is a top view of the data input unit illustrating the layout of the shift keys actuated by the thumb;
FIG. 7 is a block diagram of the data input unit and the base unit of the present invention;
FIG. 8 is a block diagram of the data input unit of the present invention;
FIG. 9 is a flow chart of the program used to generate the three types of data generated by the data input unit of the present invention;
FIG. 10 is a block diagram of the base unit of the present invention; and
FIG. 11 is a flow chart of the program used by the computer to convert signals from the data input unit into computer commands.
Detailed Description
FIGS. 1 and 2 illustrate the ergonomic design of the hand-held data input unit according to the present invention. The keyboard 1 for the four fingers of a user's hand is positioned opposite back side 2 of the unit which faces the strap or band 3. The keyboard can be grasped by a hand 4 in the manner illustrated in FIG. 4.
The hand held chord keyboard shown in FIGS. 1 and 2 has an ergonomic design that places the keyboard on the front face of the data input unit in the area normally grasped by the fingers. This design is considered optimal for typing because it enables the user to grasp the handle and type in a manner which most nearly approximates the hand movements necessary for clenching a fist. It is to be appreciated that the motion needed to clench a fist is far more natural than that needed to type on a conventional, QWERTY-type keyboard. The stress placed on the typist should therefore be minimized, thus overcoming part of the disadvantage of having to make more key strokes to generate some characters.
The data input unit in FIGS. 1 and 2 shows the right-left symmetry of the handle of the preferred embodiment. Specifically, the handle has an elongated, generally triangular cross-sectional symmetrical shape, and a flat front face. It is also designed so that the chord keyboard and other elements are arranged symmetrically so that the data input unit may be operated by the user's right or left hand. Also, band 3 can be adjusted for use by either the right or left hand. These features enable the operator to use the same unit interchangeably between the left and right hand. Velcro or similar pads 50 and 51 serve to enable adjustment of the band 3 for left or right hand usage and to adjust the tension of the band for the user's comfort
The housing 5 of the data input unit can be made of a tough, injection molded plastic. Components such as circuit boards, a tilt sensor and a battery can be embedded inside housing 5. The keys operated by the thumb of the user's hand are located on the top surface 6 of the data input unit, in the area normally grasped by the thumb so that when typing, the thumb movements approximate those necessary for clenching a fist. The top surface is generally flat and inclined at an angle to the horizontal, as shown in FIGS. 1 and 2. FIG. 4 shows how the device is held in the hand of a user and also shows a roller ball sensor 7 that functions as an alternate way of positioning the pointer.
FIG. 5 shows one possible arrangement of the keypad for the chord keyboard of the present invention. The keys are arranged in a third quadrant projection with the keys for the beginning of the alphabet in the upper right hand corner and the last keys of the alphabet in the lower left hand corner. Other arrangements are, of course, possible. The key assignments are controlled by a software look up routine so that they can be reassigned, preferably by the user.
The keys along the leftmost column in FIG. 5, specifically keys 1L, 2L, 3L and 4L, are the space key, backspace key, delete and enter keys, respectively. These functions can be generated by merely depressing and releasing the respective keys individually. Likewise, the key pads labeled A-H generate their respective characters when depressed and released. The characters written below keys R,2-4, M,2-4 and L,2-4 are generated by depressing and releasing both those keys and the keys at 1L and 1M. For example, depressing and releasing keys IL and 2R, generates the character "i", whereas depressing and releasing keys 1M and 2R generates the character "r". When more than one key is required for a character, either all keys required are depressed and released at the same time, or all keys may be depressed and held in sequence, the desired character being registered only when at least one key is released.
The center row of keys, the keys along column M, can have tiny bumps or a ridge to aid in keeping the fingers aligned. Further, the learning process can be facilitated by printing the characters on their corresponding keys. This printing can be accomplished using a color coded scheme for the characters requiring the user to depress more than one key. For example, a blue dot can be placed above key 1M and a red dot above key 1L. The blue dot would be used to generate the character on the left side below the respective key, whereas the red dot would generate the character shown on the right side. The characters could be color coded with the color of the dots so as to facilitate easier identification.
The use of twelve keys in the manner shown in FIG. 5 means that only one or two keys must be used at any given moment to generate all the characters of the alphabet. The combination of twelve keys, thus, reduces the total number of keystrokes without creating a confusing number of keys on the chord keyboard.
FIG. 6 shows the shift keyboard of the data input unit shown in FIGS. 1 and 2. Keys 41 through 46 are controlled by the thumb as shown in FIG. 4. Key 45 corresponds to the function key that converts the keys shown in FIG. 1 into function keys of the type typically set off in a separate row on a conventional keyboard. Key 42 engages the "mouse" function to send pointer position information to the computer. Key 43 corresponds to the numerical shift key used to generate numbers in conjunction with the key pad shown in FIG. 5. Key 44 represents the control key, key 46 the alternate key, and key 41 the shift key. With the exception of the "mouse" and number shift keys, these keys correspond to keys normally found spread out on a conventional, QWERTY keyboard. The present invention, however, places the keys together in one convenient place. Also, as shown in FIG. 2, the arrangement of the keys on top face 6 of the handle is symmetrical to enable right and left hand use. Variations in the thumb key designations are envisioned for certain computers such as the Apple Macintosh.
The upper and lower rows of keys 41-46 are arranged so that the thumb can depress any one key individually or two keys simultaneously. This arrangement of keys is necessary due to the command structure of personal computers. For example, "shift" and "function" are often pressed together in specific commands. The layout of keys shown in FIG. 2 facilitates this function.
FIG. 6 further illustrates two indicating LED's 47, 48 that are located on the top of the data input unit adjacent the top keyboard. LED 47 may function to indicate when the battery of the unit is low. The LED 48 can light each time that the keyboard generates a character for transmission to the base unit of the computer. The purpose of LED 48 is to provide the user with maximum feedback about the operation of the chord keyboard and the data input unit. The optional display 49 can display either data from the remote computer or from an integral computer contained within the handle.
FIG. 7 is a block diagram illustrating the wireless embodiment of the data input unit and the base unit of the present invention. The data input unit 5 is illustrated in FIGS. 1 and 2. The base unit 10 is located at the computer and communicates with the central processing unit. A data link 11 transfers data from the data input unit 5 to the base unit 10. In a hard wired version, wires may be connected directly through either the serial port or through the keyboard ports to the computer. It is also possible to establish a wireless, radio frequency link between the data input unit and the base unit. One frequency band suitable for the RF transmission is that assigned to radio frequency transmissions for equipment such as cordless telephones. The wire connection would be preferable if a large number of data input units are used within a confined space so as to minimize interference and cross talk between the units. Alternately, an infrared or ultrasonic emitter/detector system could be used in a wireless system between the data input unit and the base unit.
FIG. 8 is a block diagram of the data input unit shown in FIG. 7. The keypad 1 shown in FIGS. 1 and 2 and the thumb keypad shown in FIGS. 2 and 6 each supply data input to a microprocessor 60. The keypads can comprise contact switches and the microprocessor can be any of several well known types, such as model 8051 made by Intel or model S87C751 made by Signetics.
Sensor 61 can be a tilt sensor such as the electrolytic tilt sensor Model SP5000 manufactured by the Spectron Corporation of Hauppauge, N.Y., and is controlled by the microprocessor 60. The tilt sensor, read by the microprocessor, produces an analog signal that is digitized by an analog to digital (A/D) converter 62 and supplied to microprocessor 60. The tilt sensor and A/D converter are elements that are well known in the art. The sensor could also be a roller ball sensor, two pairs of translational motion acclerometers or a pair of angular acclerometers, all of which are known in the art and therefore not described further.
The microprocessor converts the input signals from the keyboard into three byte scan codes and transfers them to the transmission circuit 63. The transmission circuit could be a modulator for transmitting the signal wirelessly, or a direct cable or wire connection to either the serial or keyboard ports of a computer.
FIG. 9 is a flow chart showing the program executed by microprocessor 60 in the data input unit. After initialization at step 900, microprocessor 60 repeatedly determines whether data has been entered into the hand unit by scanning all the inputs to the data input unit at step 901. If no data has been received since the last scan, then the microprocessor continues to scan until some data is received.
Once data is entered, the microprocessor 60 begins to determine the type of data involved. If the mouse key 42 is depressed at step 902, microprocessor 60 generates a six byte code at step 903 corresponding to tilt information generated by the tilt sensor. The six byte code is transferred to the base unit over the communications link. The program returns to scanning its inputs at step 901 until the data input unit receives some more data. In this way, the data input unit generates pointer control information only when the user depresses mouse key 42. This feature helps to extend the life of any batteries used to power the data input unit.
The microprocessor determines at step 904 whether to repeat a key that has previously been depressed. Microprocessor 60 generates a repeat active byte at step 904 and resumes scanning at step 901. The repeat active step is determined with respect to a flag that is set in initialization step 900 and that can only be changed in subsequent processing steps described below. The basic criterion, however, is that an alphanumeric character is repeated if the same character is requested twice in succession, holding the keys down the second time. This method of repeating a character is known in the art as exemplified by IBM Technical Disclosure Bulletin Vol. 22, No. 12, May, 1980 by F. C. Bequaert, and therefore will not be described further here.
Microprocessor 60 determines at step 906 whether any key has been released in the current scan cycle. If it has not, microprocessor 60 returns to scanning its inputs at step 901 without taking further action.
After step 907, the microprocessor knows that the data input it has received came from the release of a key on the chord keyboard--either from the keyboard 1 or the shift keys 41-46. At step 907 the microprocessor determines if the mouse key 42 was released. If yes, then the microprocessor generates a mouse clear byte to the base unit at step 908 and returns to scanning for input at step 901. The microprocessor determines at step 909 if the repeat key was previously active. If it was, then the microprocessor assumes that the key is no longer to be repeated and generates a one byte command at step 908 to clear the repeat function before resuming scanning at step 901.
By the time the microprocessor reaches step 911, it has exhausted all other possibilities; the input data received by the microprocessor corresponds to a keyboard scan code. Microprocessor 60 then generates a three byte code indicative of the scan code input and returns to scanning for additional input at step 901.
FIG. 10 is a block diagram of the base unit 10 shown in FIG. 7. The communications link 11 transfers the input data signal from the data input unit to the receiver 81. A demodulator unit 82 demodulates and formats the scan codes from the data input unit for transmission to the computer. The base unit 10 can have connections to the keyboard port 83, mouse port 84, RS232 port 85 or the bus 86 of the computer--a range of inputs normally available on a computer.
FIG. 11 is a flow chart of the steps executed by the Terminate Stay Resident (TSR) program in the computer in response to input data being received from the data input unit. Upon generation of an interrupt at step 912 caused by a data present signal, the computer systematically proceeds to determine whether the input is any of three types generated by the data input unit--six byte mouse data, three byte key codes or one byte special function data.
The computer determines whether the input data received from the data input unit is six byte mouse data at step 913. If it is, then the data is directed to mouse driver software at step 914. The computer then exits the interrupt routine.
The computer determines whether the scan code from the data input unit is a character code at step 915. If it is, then program executes a subroutine at step 916 in which the three byte code can be transformed using a look up routine into a code that the computer can understand. Once this is done, however, the computer still must determine what kind of data it is. This determination is made at step 917 by asking whether the character from the look up routine is a recognized ASCII character. If it is, then it is placed in the keyboard buffer at step 918. Any character that is not in ASCII is a special function such as a number lock or caps lock command. The computer then exits at step 925.
At this point the computer determines at step 920 whether the code from the data input unit is a repeat byte. If it is, the computer repeatedly places the last ASCII character generated in step 916 back into the keyboard buffer. The character will continue to repeat until the computer recognizes a repeat clear character at step 922 generated by the data unit upon release of the key(s) and stops the character generation at step 923. In either instance the computer ultimately exits again at step 925.
Any character that has not been recognized up to this point is presumed to be a mouse clear character corresponding to a release of the mouse key at step 924. The computer then again exits the character generation routine at step 925.
Although key assignments may be changed by the user, an exemplary set of key assignments for generating input data for the computer is as follows:
The foregoing table is one example of the key assignments which can be made; the assignments can be reprogrammed to customize the data input unit as desired.
The software for the microprocessor functions described above in connection with the data input unit may comprise the following listings, which are written in PLM and assembler language respectively, for the Signetics S87C51 microprocessor. ##SPC1##
It should be noted that this program is a terminate stay resident program which is co-resident with other programs. The listings include a key assignment table similar to that set forth above but which is a subset of that described in the table excluding the F1, F2 functions. As will be noted, the key assignment table contains ASCII characters represented by hexidecimal code.
The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. The invention which is intended to be protected herein should not, however, be construed as limited to the particular teachings of the specification because they merely illustrate the invention defined in the following claims.
Claims
What is claimed is:
1. A data input device for interfacing with a computer, comprising: an ergonomically designed handle that can be operated by a hand of a user by curling the fingers of the hand around the handle and pressing keys with the tips of the fingers; a chord keyboard integral with the handle for generating character data, the chord keyboard being mounted on the handle so that input data for the computer can be generated when the fingers of the user's hand are curled around the handle, the chord keyboard including a first keypad mounted on the handle and located adjacent the four fingers of the hand of the user when the fingers are curled around the handle to type; a second keypad mounted on the handle and located adjacent the thumb of the user when the thumb is curled around the handle to type; and a support band adapted to fit around the hand of the user, the band being attached to the handle for pressing the handle into the palm of the hand of the user so the device may be held in the hand without the hand gripping the device without other means of support and operated by depressing and releasing the keys with the tips of the fingers of the hand supporting the device, wherein the handle has a left-right symmetry and the first and second keypads are arranged on the handle with a left-right symmetry and the support band can support either the left or right hand so that the data input device can be operated by either the right hand or left hand of the user.
2. The data input device as recited in claim 1, wherein the handle further comprises a microprocessor for generating the input data.
3. A data input device as recited in claim 2, wherein the computer includes a look-up table in which is stored character information correlated to the chords, wherein the computer reads character information from said lookup table based on the input data generated by the microprocessor.
4. A data input device as recited in claim 3, wherein: the first keypad comprises an array of individual keys in rows and columns; and wherein the look-up table provides an assignment of the characters to the keys and chords on the first keypad in alphabetical order.
5. A data input device as recited in claim 1, wherein the handle further comprises a display for generating visual symbols corresponding to information received by the data input device from the computer.
6. A data input device as recited in claim 2, further comprising a sensor coupled to the microprocessor for generating pointer position information for the computer.
7. The data input device of claim 6 wherein said sensor comprises a tilt sensor.
8. The data input device as recited in claim 6 wherein said sensor comprises a plurality of angular accelerometers.
9. The data input device of claim 1, wherein said support band is adjustable in length and in angular position with respect to a circumference of the ergonomically designed handle to custom fit the grip of the device to the size of the hand of the user.
10. A data input device, having a plurality of keys, for interfacing with a computer, comprising: an ergonomically designed handle that can be operated by a hand of a user by curling the fingers of the hand around the handle and depressing and releasing the keys with the tips of the fingers; a chord keyboard integral with the handle for generating input data for the computer, the chord keyboard being integral with the handle and mounted so that the input data can be generated when the fingers of the hand are curled around the handle and the keys are depressed and released, wherein the handle has a left-right symmetry and the keys of the chord keyboard are arranged with left-right symmetry on the handle, so that the data input device can be operated by either the right or left hand of the user.
11. A data input device as recited in claim 8, wherein the chord keyboard further comprises: a first keypad including a plurality of keys mounted on the handle at a location adjacent where the four fingers of the hand of the user curl around to operate by pressing and releasing; and a second keypad including a plurality of keys mounted on the handle at a location adjacent where the thumb of the user curls around the handle to operate by pressing and releasing; and wherein the handle further comprises, a first set of labels for indicating which keys on the first keypad will generate a given character; and a second set of labels identifying keys on the second keypad.
12. A data input device as recited in claim 11 wherein the labels of said first and second sets of labels are embossed on the handle of the data input device.
13. The data input device of claim 9 wherein said first and second set of labels comprise templates.
14. A data input device as recited in claim 10 wherein the keys of the chord keyboard are of such number and arrangement that any of a plurality of keys is accessible to and can be pressed and released by each of the five digits of the hand.
15. A data input device as recited in claim 10 wherein the ergonomically designed handle comprises a plurality of keypads, all of the keys of which may be released without any contact required between keystrokes.
16. A data input device as recited in claim 10 wherein the ergonomically designed handle further comprises an adjustable support and adjustment band traversing the back of the operating hand.
17. A support and adjustment band as recited in claim 16 wherein the band is attached to the handle so as to press the handle into the palm of the operating hand without the user having to grip the handle.
18. A support and adjustment band as recited in claim 16 wherein the band is adjustable in both length and orientation to fit the hands of different users.
19. A data input device as recited in claim 10 wherein the chord keyboard further comprises keypads having keys with labels which are visible to the user between keystrokes during normal operating use.
20. A data input device as recited in claim 10, further comprising a microprocessor coupled to the keyboard for generating the input data for the computer.
21. A data input device as recited in claim 20, wherein a look-up table stores character information correlated to the chord, wherein the computer reads character information from said look-up table generated by the keyboard based on the input data generated by the microprocessor.
22. A data input device as recited in claim 21, wherein: the first keypad includes an array of individual keys in rows and columns; and wherein the look-up table provides an assignment of the characters to the keys and chords on the first keypad in alphabetical order.
23. A data input device as recited in claim 20, further comprising a sensor coupled to the microprocessor for generating pointer position information for the computer.
24. The data input device of claim 23 wherein said sensor comprises a tilt sensor.
25. The data input device as recited in claim 23 wherein said sensor comprises a plurality of angular accelerometers.
26. A data input device as recited in claim 10, further comprising a display for generating visual symbols corresponding to information received by the data input device from the computer.
27. The cybernetic interface of claim 28, wherein said support band is adjustable in length and angular position with respect to a circumference of said ergonomically designed handle to custom fit the grip of the device to the hand of the user.
28. A cybernetic interface for use with a computer, comprising: an ergonomically designed handle, adapted to be operated by a hand of a user; a chord keyboard integral with the handle for generating input data for the computer; a support and adjustment band adapted to fit around the hand of the user, the band being mounted on the handle so as to press the handle into the palm of the hand without the user having to grasp the handle so as to adjust to fit the hand of the user; and a communications link coupled to the keyboard and the computer, the communications link enabling transfer of the input data from the keyboard to the computer, wherein the handle has a left-right symmetry and the keys of the chord keyboard are arranged with left-right symmetry on the handle so that the interface can be operated by either hand of the user.
29. A cybernetic interface as recited in claim 28, wherein the chord keyboard further comprises: a first keypad mounted on the handle at a location below where the four fingers of the hand of the user curl around the handle to operate by pressing and releasing the keys; and a second keypad mounted on the handle at a location below where the thumb of the user is positioned to operate by pressing and releasing the keys.
30. A cybernetic interface as recited in claim 29 wherein said first and second keypads each include a plurality of keys and wherein the handle further comprises: a first set of labels for indicating which keys or combination of keys on the first keypad produce a given character; and a second set of labels for identifying keys on the second keypad.
31. A cybernetic interface as recited in claim 30 wherein the labels of said first and second sets of labels are embossed on the handle.
32. The cybernetic interface of claim 30 wherein said first and second set of labels comprise templates.
33. A cybernetic interface as recited in claim 28, further comprising a microprocessor for generating the input data for the computer.
34. A cybernetic interface as recited in claim 33, further comprising a look-up table in which character information correlated to the chords generated by the keyboard based on the input data is stored.
35. A cybernetic interface as recited in claim 34, wherein: chord keyboard includes a first keypad including an array of individual keys in rows and columns; and wherein the look-up table provides an assignment of the characters to the keys and chords on the first keypad in alphabetical order.
36. A cybernetic interface as recited in claim 28, wherein the communications link comprises; data transmission means for transmitting the input data generated by the chord keyboard; and data receiving means for receiving the input data from the transmission means, the receiving means being adapted for transferring the input data to the computer.
37. A cybernetic interface as recited in claim 28, further comprising means for displaying symbols corresponding to information received by the interface from the computer.
38. A cybernetic interface as recited in claim 28, wherein the handle further comprises a sensor for generating a pointer position information.
39. The cybernetic device of claim 38 wherein said sensor comprises a tilt sensor.
40. The cybernetic device as recited in claim 38 wherein said sensor comprises a plurality of angular accelerometers.
41. A data input device for a computer, comprising: a chord keyboard means for generating input data for the computer adapted to be operated by a hand of a user so that input data can be generated by movement of the fingers of the hand; and means for supporting the keyboard in the hand of the user when the user operates the keyboard means, the supporting means pressing the keyboard means into the palm of the operating hand of the user, wherein the chord keyboard means has a left-right symmetry so that the data input device can be operated by either the right or left hand of the user.
42. A data input device as recited in claim 41, wherein the chord keyboard means further comprises: character keys arranged in an array of rows and columns on the chord keyboard means; and means for assigning characters to the character keys and chords on the keyboard means in alphabetical order based on the input data generated by the keyboard means.
43. A data input device as recited in claim 42, wherein the chord keyboard means further comprises means for indicating the keys to be pressed to produce a given character.
44. A data input device as recited in claim 41, further comprising sensor means for generating pointer information.
45. The cybernetic device of claim 44 wherein said sensor comprises a tilt sensor.
46. The cybernetic device as recited in claim 44 wherein said sensor comprises a plurality of angular accelerometers.
47. A hand held computer interface device comprising: a base; a first generally planar wall extending upwardly from said base; a contoured surface cooperating with said base and first wall to form a closed three dimensional elongate member in the form of a handle with a circumference; a first keyboard disposed on said first wall; and a second keyboard on said contoured surface at a point accessible to a thumb of the user, wherein the second keyboard is disposed on said contoured surface so as to be accessible by a user's left thumb if the device is held in the left hand and is accessible by a user's right thumb if the device is held in the right hand.
48. The hand held computer interface of claim 47 wherein said circumference is selected so that a human hand can curl about said handle with a finger tip being positioned above said first keyboard.
49. The hand held computer interface device of claim 47 wherein said first keyboard comprises a plurality of keys activated by depression by a finger tip of fingers of a hand operating the device.
50. The hand held computer interface of claim 47 further comprising a support band adapted to fit around the hand of the user, the band being attached to the handle for pressing the handle into the palm of the hand of the user so the handle may be held in the hand and operated by depressing keys on the first keyboard with the tips of the fingers of the hand supporting the device with the band without other means of support.
51. The hand held computer interface device of claim 50 wherein said support band is adjustable in length and in angular position along the contoured surface to custom fit the grip of the device to the hand of the user.
52. The hand held computer interface of claim 51 comprising a microprocessor for generating input data for a computer coupled to the interface device.
53. The hand held computer interface of claim 47 comprising a microprocessor for generating input data for a computer coupled to the interface device.
54. The hand held computer interface device of claim 53 further comprising a sensor coupled to the microprocessor, for generating pointer position information for the computer.
55. The cybernetic interface as recited in claim 54 wherein said sensor comprises a plurality of angular accelerometers.
56. The cybernetic device as recited in claim 54 wherein said sensor comprises a tilt sensor.
57. A hand held computer interface unit comprising: an elongated handle having a first and a second face, and a contoured body supporting said first and second faces, the contours of the body being adapted to fit in the operating hand of a user; and a first and second keyboard, for the fingers and thumb respectively, positioned on the first and second faces, wherein the fingers and thumb of the operating hand curl around the contoured body to position the tips of the fingers and thumb of the operating hand above said first and second keyboards; and a plurality of keys disposed on said first and second keyboards, said plurality of keys adapted to be activated when depressed by the tips of said fingers and thumb, and said keys generating input and control information when depressed and released wherein said fingers and thumb are above said first and second keyboard when not operating the keys of the respective keyboards, wherein the second keyboard is disposed on said contoured surface so as to be accessible by a user's left thumb if the device is held in the left hand and is accessible by a user's right thumb if the device is held in the right hand.
58. The hand held computer interface of claim 57 further comprising a support band adapted to fit around the hand of the user, the band being attached to the handle for pressing the handle into the palm of the hand of the user so the handle may be held in the hand and operated by depressing keys on the keyboard with the tips of the fingers of the hand supporting the device with the band without other means of support.
59. The hand held computer interface device of claim 58 wherein said support band is adjustable in length and in angular position along the contoured surface to custom fit the grip of the device to the hand of the user.
60. The hand held computer interface device of claim 59 comprising a microprocessor for generating input data for a computer coupled to the interface device.
61. The hand held computer interface device of claim 57 comprising a microprocessor for generating input data for a computer coupled to the interface device.
62. The hand held computer interface device of claim 61 further comprising a sensor coupled to the microprocessor, for generating pointer position information for the computer.
63. The cybernetic device as recited in claim 62 wherein said sensor comprises a plurality of angular accelerometers.
64. A hand held computer interface unit comprising: an elongated handle having a first face, and a contoured body supporting said first face, the contours of the body being adapted to fit in the operating hand of a user; and, a first keyboard positioned on said first face, wherein the fingers of the operating hand curl around the contoured body to position the tips of the fingers of the operating hand over a plurality of keys disposed on said first keyboard, said plurality of keys generating input and control information when depressed and released and wherein the design of said handle is such that is it maintained in position in the hand while the tips of the fingers of the operating hand are positioned above but not in contact with the keys disposed on said first keyboard; and a second keyboard positioned on a second surface of said handle and having a plurality of keys which can be manipulated by the thumb of the operating hand, wherein the keys of said second keyboard are adapted to be activated when depressed and released by the thumb of the operating hand, wherein the second keyboard is disposed on said contoured surface so as to be accessible by a user's left thumb if the device is held in the left hand and is accessible by a user's right thumb if the device is held in the right hand.
65. The hand held computer interface of claim 64 further comprising a support band adapted to fit around the hand of the user, the band being attached to the handle for pressing the handle into the palm of the hand of the user so the handle may be held in the hand and operated by depressing keys on the keyboard with the tips of the fingers of the hand supporting the device with the band without other means of support.
66. The hand held computer interface device of claim 65 wherein said support band is adjustable in length and in angular position along the contoured surface to custom fit the grip of the device to the hand of the user.
67. The hand held computer interface device of claim 66 comprising a microprocessor for generating input data for a computer coupled to the interface device.
68. The hand held computer interface device of claim 64 comprising a microprocessor for generating input data for a computer coupled to the interface device.
69. The hand held computer interface device of claim 68 further comprising a sensor coupled to the microprocessor, for generating pointer position information for the computer.
70. The cybernetic device as recited in claim 69 wherein said sensor comprises a plurality of angular accelerometers.
71. The cybernetic device as recited in claim 69 wherein said sensor comprises a tilt sensor.
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