Coordinators: Ninad Jog and Gary Withrow

Allophone: Variation on saying phonemes.

Analog: An analog voltage or signal refers to the continuous nature of valid voltage potentials in analog circuits. An analogy of the difference between digital and analog signals is like the difference between real numbers and integers; real numbers are continuous from 0.0 to 1.0 like analog voltage potentials between 0.0 Volts and 1.0 Volts, but the only integers in this range are 0 and 1 like discrete digital voltage potentials between 0.0 Volts and 5.0 Volts; see "digital."

Analog-to-digital converter: A device that transforms continuous (analog) signals, such as voice inputs, into discrete (digital) voltages.

Annular ligament: Attaches the stapes to the oval window.

Artificial Reality: Non-immersive computer-controlled responsive environments. The full-body motion of the participant effects the computer-generated environment, displayed on a screen. Term coined by Myron Krueger.

Auditory Cognition: The study of psychological effects derived by the auditory system.

Augmented Reality: The use of transparent HMDs to overlay computer generated images onto the physical environment. Precisely calibrated, rapid head tracking is required to sustain the illusion.

Axon: A portion of a neuron that connects dendrites together.

Basilar membrane: A thin membrane that separates the cochlea into two sections.

Binaural (3-D) Sound: Filtered sound that appears to come from different locations in space relative to the listener. The device that generates it is called a convolvotron.

Biosensors: Transduceres that detect muscle activity and send electrical signals.

Body Suit: A piece of apparel covering the entire body, wired with "biosensors" for reading the positions of any part of the body.

Coarticulation: The practice of running together adjacent words in a spoken phrase. In some more extreme cases, the final sounds of the first word are lost in the beginning of the second word.

Cerebral cortex: The large significant area of the brain.

Cochlea: A spiral-shaped structure in the inner ear that contains the organ of Corti.

Convolvotron: See "Binaural (3-D) Sound"

Corti: The primary organ responsible for hearing in the human ear.

Cybernaut: A person experiencing "Virtual Reality.

Cyberspace: A medium formed by computer networks that provides a sensory experience to its users. Term coined by William Gibson.

DataGlove: Trademark of VPL Research. See "Glove".

Dendrites: These surround the cell and form the synaptic gap.

Dictionary Units: Library of experienced sounds stored in memory.

Digital: A digital voltage or signal refers to the discrete nature of digital voltage potentials in digital circuits. TTL (Bipolar Transistor-Transistor Logic) defines 0.0 Volts as a logic 0 or low, and 5.0 Volts as a logic 1 or high; These are single values for clarity - there are actually ranges of voltage potentials around 0.0V and 5.0V which are recognized as low and high logic levels, respectively. See "analog" for an analog/digital analogy.

Digital Vocal Tract Modelling: Voice Synthesis by modelling the human vocal tract.

Diphthong: Sound which cannot be represented by a single symbol, usually between successive phonemes.

Effectors: Input and output sensors that communicate a user's movements or commands to the computer or provide sensory stimulation from the computer to the user.

Eustachian tube: The air passage into the middle ear that allows equalization.

Feature analysis: The method of voice recognition where words and phrases are distinguished from each other based on differences in certain characteristics of the sounds. These characteristics include pitch, timing, frequency content, and envelope contours.

Force Ball: Ball-shaped force and torque transducer used as a navigational device.

Force Feedback: See Tactile Feedback

Format Frequency Synthesis: Voice synthesis by concatenating phonetic sounds.

Fourier transform: The mathematical procedure for determining the frequency components of a particular signal. In essence, this procedure shows what high, medium, and low sounds, and what volume of each, are combined to make a complex sound like the human voice. This information is used in the feature analysis method of voice recognition.

Gesture Recognition: The use of transducers to recognize user's movements to alter the reality being presented to the user.

Glove: A glove wired with "Biosensors" to detect hand and finger motions.

Goggles: See "Head-Mounted Display (HMD)"

Haptic Perceptions: Sense of touch at the skin and force feedback information from muscles and joints.

Head-Mounted Display (HMD): A graphical display device, such as a pair of tiny LCD screens worn like goggles. Often combined in a single helmet with position tracking sensors and earphones for 3-D sound.

Head-up display (HUD): A transparent, optical-quality piece of glass that is placed directly between the pilot and the windscreen in front of the pilot. Computer-generated information is projected onto this glass, and as the pilot looks through the HUD, the pilot sees both the scene in front of the aircraft and the projected information. This arrangement allows the pilot to see important flight information (airspeed, altitude, heading) without having to look down at the instrument panel in the cockpit.

Immersion: When several of a user's senses are isolated from the real world and fed information (images and sound) coming from a computer.

Incus: The "anvil" of the ossicles that the malleus is coupled to.

Instrument flying: To fly an airplane using only its instruments for guidance. Instrument flying is usually performed at night or in bad weather when the pilot cannot see the ground or the horizon and use them as references.

Labyrinth: The general term for bony labyrinth and membranous labyrinth.

Larynx: An enlargment of the upper end of the windpipe, containing the vocal cords.

Linear predictive coding: A voice filtering method, used primarily by Texas Instruments, that mathematically filters an incoming voice sample into 20-millisecond segments. These segments are then compared to stored segments, using template matching techniques, to determine the identity of the input.

Linguistics: The science of language.

Malleus: The "handle" of the ossicles that attaches to the eardrum.

Meatus: The ear canal.

Neuron: A cell that transmits nerve impulses in the human body.

Ossicles: The name for three tiny bones in the middle ear, the incus, malleus, and stapes.

Oval window: Membrane that is between the middle and inner ear.

Perilymph: membrane between the stapes and the round window.

Phoneme: The phonetic alphabet.

Pinna: Oval shaped cartiledge portion of the external ear.

Projected Reality: A computer system which uses projection televisions to provide an individual or group with a window to a virtual environment.

Real-Time Image Processing: Manipulation of live images, typically within 50 to 100 milliseconds, so the human user percieves them as instantenous.

Reality Engine: A computer system specifically designed to generate virtual reality worlds.

Reissners membrane: Breaks the vestibular gallery into two sections.

Rendering: The process of calculating image details and drawing them on a screen.

Saccule: One of the two fluid-filled sacs in the cochlea separated by the basilar membrane.

Scala media: The "Reissners membrane".

Signal-to-noise ratio: The signal-to-noise ratio or S/N is the ratio of the desired signal power over the power of the noise that is present. A higher S/N is desirable in audio applications for more noise immunity; a circuit with a low S/N is more susceptible to noise.

Smart weapon: A weapon, usually a bomb or missile, that can be steered toward its target, even if the weapon was not launched directly toward the target. Steering commands are generated by the weapon itself if the weapon is autonomous, and by a weapon controller if the weapon is remotely controlled.

Spaceball: A 6d stationary input device.

Stapes: The narrow third bone in the ossicles, the incus attaches to the stapes.

Stapedius muscle: Attaches the stapes to the wall of the middle ear.

Stereoptic Display: A display that creates the illusion of a three-dimensional world.

Synapse: The name for the gap formed by the dendrites of two neurons connecting.

Tactile Feedback: A glove that uses air pressure or vibration to apply force to the wearer's hand, giving a realistic perception when virtual objects are held.

Telepresence: The remote operation of a robotic system with the aid of an immersive human interface.

Template matching: The method of voice recognition where words and phrases are identified by matching those words and phrases to samples of words that have been previously stored in the computer.

Temporal lobe: One of the several lobes in the cerebral cortex, responsible for auditory senses.

Texture mapping: Displaying a single digitized image on a polygon or structure that is made of polygons. Creates a heightened sense of realism in images.

Tympanic gallery: One of the sections of the cochlea.

Unencumbered Virtual Reality: A virtual reality experience without the cumbersome paraphernalia like wired HMDs, speakers, etc.

Utricle: One of the two fluid-filled sacs in the cochlea separated by the basilar membrane.

Vestibular gallery: One of the sections of the cochlea.

Virtual Prototyping: Using virtual reality to create product prototypes and test their properties.

Virtual Reality: A human-computer interface in which the computer creates a sensory-immersing environment that interactively responds to and is controlled by the behavior of the user.

Voice recognition: The technology by which sounds, words or phrases spoken by humans are converted into electrical signals, and these signals are transformed into coding patterns that can be identified by a computer. Based on this identification, the computer usually takes some action.

Voltage comparators: A voltage comparator is an electronic device with two inputs, positive and negative, whose function is to drive a high or low level onto its output, depending upon which input has a more positive voltage potential. If the positive input has a more positive voltage potential than the negative input, the output will be driven to a high level; a low level is driven on the output when the negative input has a higher voltage potential.

Wand: An input device with three degrees of freedom.

Waveform Encoding: Recording and playback of analog phrases to digital storage.

Wire-Frame Image: A 3-D drawing in which only the edges of objects are drawn.


[PIMENTEL 1993] Pimentel, Ken and Teixeira, Kevin, "Virtual Reality", Intel/ Windcrest/McGraw-Hill, 1993

[Internet] Frequently Asked Questions (FAQ) of newsgroup sci.virtual-worlds

[DeFANTI 93] DeFanti, Sandin and Cruz-Neira, "A 'room' with a 'view', IEEE Spectrum, October 1993, pp. 30-33

[Table of Contents]

Human Interface Technology Laboratory