Patent No. 7038659 Symbol encoding apparatus and method

 

Patent No. 7038659

Symbol encoding apparatus and method (Rajkowski, May 2, 2006) 

 Abstract

An apparatus and method of encoding and communicating symbols is provided. A user encodes a symbol using a sliding motion of a fingertip in relation to a proximity and touch-detecting glance pad. The user imagines a polygon on the surface of the pad. The user makes an encoding touch generally coextensive with one of the sides of the polygon in either a clockwise or counterclockwise direction. The glance pad detects the motion and infers the intent of the user, assigning a symbol to the encoding touch.

Notes:

RELATED APPLICATIONS

This application is related to and claims priority from provisional patent application No. 60/370,278 filed by Janusz Wiktor Rajkowski on Apr. 6, 2002.

 

BACKGROUND

1. Field of the Invention

The present Invention relates to a method and apparatus for inputting or communication of symbols, such as alpha-numeric characters, using a motion and touch detecting surface.

2. Description of the Related Art

The human mind communicates with the world through the muscular contractions that result in speech and gestures. The human hand is capable of precise, complex motion and has great potential as a means of communication.

Previous attempts to exploit hand motion as a mode of communication have resulted in methods that are relatively slow and cumbersome. The typewriter was the first successful mechanical device using hand movements to communicate complex thoughts. The design of the familiar typewriter keyboard was constrained by mechanical considerations. With the advent of computers, the mechanical considerations disappeared, but the typewriter keyboard remained. A modified typewriter keyboard was combined with a computer mouse and adopted as the human-to-machine interface of choice. No subsequent challenges compromised the dominant role of the keyboard/mouse combination.

There are two reasons for the lasting appeal of the familiar typewriter keyboard. First, the keyboard may be used by an untrained operator and typing skills may be acquired gradually. Second, a skilled typist may produce text very rapidly. To achieve a high rate of typing speed, the skilled typist utilizes the propensity of the brain for parallel processing in which separate neural networks control the motion of each finger. As the typist learns to type, combinations of movements become preprogrammed sequences of neural commands. As the skilled typist works, the preprogrammed movements are stacked in the brain circuits ready for subsequent subconscious execution. By distributing the work load between the two hands and among the ten fingers, the skilled typist may produce text at a speed matching the pace of casual speech.

The typewriter keyboard has several disadvantages. First, a full-size keyboard suitable for high-speed operation is bulky and not easily transported. Second, the keyboard must be operated with both hands to achieve speed and accuracy. Third, the typist must conform his or her posture to the requirements of the keyboard; namely, sitting or standing facing the keyboard with the keyboard at the proper height and angle.

Several improvements to the typewriter keyboard have been proposed. Among the most notable is the chorded keyboard. The user of a chorded keyboard strikes multiple keys using multiple fingers at one time to enter a single character. The advantage of the chorded keyboard is that far fewer keys are needed, allowing the chorded keyboard to be used with one hand. A chorded keyboard may be hand-mounted or hand-held and may be operated away from the desk. Chorded keyboards require complex encoding schemes and complex, multidimensional, multi-joint finger motions and require a return to a resting position following each encoding motion. As a result, chorded keyboards can be operated only at a low speed, even by a skilled operator.

Virtual keyboards are available and are smaller and less obtrusive than the bulky physical keyboard. Virtual keyboards emulate typewriter keyboard operation, including the typewriter keyboard layout. Virtual keyboards employ remote sensing technologies to track finger motions with finger motion tracking devices placed in front of the keyboard or mounted on the hand. The user performs the hand movements of typing on a tabletop and the motion tracking devices translate the finger motions into the keystrokes of a typewriter.

Virtual keyboards share many of the disadvantages of the physical keyboard; namely, a tabletop area is required for operation, the operator must adopt a posture in front of the virtual keyboard, and the operator must type using two hands to achieve rapid operation. An additional disadvantage of the virtual keyboard is the lack of tactile feedback to the user.

Patents related to virtual keyboard technology include U.S. Pat. No. 6,304,840 to Vance issued Oct. 1, 2001 entitled "Fingerless glove for interacting with data processing system" and U.S. Pat. No. 5,767,842 to Koch, issued Jun. 16, 1998, entitled "Method and device for optical input of commands or data." Virtual keyboard devices are marketed by Samsung Scurry and may be seen on the company website at www.samsung.com. Another virtual keyboard device is marketed by Senseboard Technologies and can be viewed on the company website at www.senseboard.com. The company `Virtual Devices` also markets a virtual keyboard.

Prior art devices for sign language gesture recognition are based on similar principles and provide for free space hand motion tracking.

Touch sensitive tablets or display overlays also have been developed. Touch sensitive tablets may use a typewriter keyboard layout or a chorded keyboard layout and may add enhancements unavailable in a physical keyboard, mostly through integrating the functions of a keyboard and of a cursor positioning device.

Several touch-sensing and proximity detection technologies are well known in the art; among those technologies are membrane or mechanical switches, resistive membranes, acoustic, capacitive, inductive and optical sensors. Many of these devices use a row and column grid of intersecting conductors or similarly arranged matrix of individual sensing elements. Capacitive sensing technology is among the most popular because it is capable of sensing the presence of a finger up to several millimeters away from a sensing device ("proximity sensing"). Capacitive sensing technology allows for zero-force, virtually touchless data entry or manipulation of an object on a screen.

Several multi-finger contact detectors have been proposed. Most are based on capacitive sensing technology. Multi-finger contact detectors are capable of detecting multi-finger-coordinated gestures and are designed for manipulative interactions with complex applications. Examples of such multi-finger contact detectors are as follows:

S. Lee, "A Fast Multiple-Touch-Sensitive Input Device", University of Toronto Master's Thesis (1984);

U.S. Pat. No. 5,194,862 to Edwards issued Mar. 16, 1993 entitled "Touch sensor array systems and display systems incorporating such";

U.S. Pat. No. 5,463,388 to Boie issued Oct. 31, 1995, "Computer mouse or keyboard input device utilizing capacitive sensors";

U.S. Pat. No. 5,844,506 to Binstead issued Dec. 1, 1998 and entitled "Multiple input proximity detector and touchpad system"; and

U.S. Pat. No. 5,825,352 to Bisset issued on Oct. 20, 1998, entitled "Multiple finger contact sensing method for emulating mouse buttons and mouse operations on a touch sensor pad".

Additional developments have been directed to integrate different types of manual input. Typing, manipulation and handwriting capacities are taught by U.S. Pat. No. 6,323,846 to Westerman issued on Nov. 27, 2001, entitled "Method and apparatus for integrating manual input."

Each of the prior art approaches reviewed above has one or more of the following disadvantages:

(a) the approach requires conformation to the posture required by the keyboard (typewriter keyboard, virtual keyboard);

(b) the approach does not provide good tactile feedback (virtual keyboard).

(c) the approach involves complex multi-joint, unnatural motions, resulting in slow output (chorded keyboards);

(d) the approach requires forceful, large-amplitude hand 12 motions followed by wasted motion to the neutral resting position (chorded keyboard);

The apparatus and method of the present Invention overcome the foregoing disadvantages of the prior art.

SUMMARY OF THE INVENTION

The present Invention is a method and apparatus for communication, particularly for inputting symbols into a computer or communication device. The method of the invention comprises moving a finger or other object to encode an information item. Such motion by a finger or other object is referred to herein as a "glance." The apparatus of the invention is a "glance pad" (as hereinafter defined) that detects the finger motion coupled with associated processing apparatus that interprets the finger motion.

From the perspective of the user, each `glance` is a sliding touch by a fingertip or by the pad of the terminal joint of a finger against a glance pad, the touch being along one of the sides of a rectangle assigned to that finger. The sliding touch has location and direction. In making a glance, the user selects a finger to make the glance, selects one of the four sides of the rectangle assigned to that finger, and selects one of the two possible directions of motion (clockwise and counterclockwise with respect to the rectangle) along the selected side. Each finger therefore can produce eight different "glance motions" and can encode at least eight different symbols. Four fingers of one hand can encode more than the twenty-six letters of the alphabet.

The rectangle of the foregoing description is not a physical object. The rectangle is imaginary and exists only as a conceptual aid for the user. From the perspective of the user, each rectangle moves with the finger to which the rectangle is assigned so that the user may reach for the imaginary side of the imaginary rectangle from any position of the user's fingers on the glance pad.

From the perspective of the glance pad and invention apparatus, each glance has two components: a "proximity component," also called an "approach trajectory," and an "encoding touch." The encoding touch is the sliding touch by a finger of the user to the glance pad. The direction of motion of the finger immediately prior to and immediately after the start of the encoding touch defines a `touch vector.` The motion of the finger beginning at a predetermined time prior to the start of the encoding touch and ending at a predetermined time with respect to the start of the encoding touch defines an `approach vector.` Together, the approach vector and the touch vector reveal which of the eight different possible glance motions the user intended. The apparatus consults a library of symbols and selects the symbol encoded by the particular glance motion intended by the user.

The apparatus employs various strategies to screen data received to eliminate spurious data and to interpret ambiguous or incomplete information generated by a finger motion. Those strategies include evaluating the simultaneous motion of more than one finger to infer the motion of the finger making an encoding touch.

The glance pad of the invention is a proximity and touch-sensing device using any of the suitable conventional technologies known in the art, including technologies based on light, capacitance, inductance, acoustic energy, mechanical switches or any other suitable technology or combination of technologies capable of detecting the presence and spatial arrangement of a plurality of objects, especially fingers of a user, on or near the sensing surface. The sensing device comprises an array of proximity and touch sensing nodes coupled to a microprocessor and further includes appropriate software controlling the microprocessor. The microprocessor and software interpret data generated by the proximity sensing nodes and select an encoded symbol from a library of symbols contained in memory. The apparatus generates an output signal, encoding and communicating the selected symbol.

The information item encoded by a glance can be an alphanumeric character, word, number, executable computer program, or group of characters, words or numbers, or any other item of information. As used in this application, the term "symbol" means any item of information of any nature capable of being assigned to a particular glance, but does not include information to determine the location of a cursor on a computer screen.

As used in this application, the term "glances" means the glancing motion of a finger acting in concert with and cooperating with the glancing motions of other fingers. The activity of encoding a symbol is referred to herein as "glancing."