THE HUMAN INTERFACE IN THREE DIMENSIONAL COMPUTER ART SPACE By Jennifer A. Hall B.F.A. Kansas City Art Institute 1980 Submitted to the Department of Architecture in partial fulfillment of the requirements for the degree of Master Of Science in Visual Studies at the Massachusetts Institute Of Technology October 1985 Copyright 1985. JAHall. All rights reserved. The author hereby grants MIT permission to reproduce and to distribute publicly copies of this thesis document in whole or in part. 1 / I/ .. . .. Signature of author......en.. r Hall epartment.of Architecture October 16, 1985 " Certified by. .............................................. Professor Otto Piene Director, Center For Advanced Visual Studies Thesis Supervisor .......... .................... Professor Nicholas Negroponte Chairman, Department Committee for Graduate Student Accepted by............... OCT Sc Acknowledgement I am grateful Advanced to The Center For Visual The Archit.ecture Machine Group, and the patience the involved individuals who allowed me of Studies, the many freedom to construct my own special space at MIT. My thanks, also, Aesthetic Confidant, and to Patrick friend, Purcell, and to my my editor, Roberts, who saved not only me, but countless inocent hours of tedious paper crunching. ii :) Professor, Shelly victims, Table of Contents Section I . Introduction ................. . - --- . -. -.-- -Pg 1 .Pg 3 Defining 3D Space............ .. 3 Physical Computer Space.... Logical Programming Space.. .Pg 4 Impressed Graphics Space... .Pg 5 Neurological Representations. ... . Computer as Artifact............. .... ...... ....... ..... .. Machine Vision................... ... Pg 8 ... Pg 11 .Pg 18 Qualitive Considerations of Machine Vision............. ... Pg 18 .Pg20 Gesture Analysis.............. Computer Constructed Motion... 21 Computer Controlled Tracking.. Pg 23 iii .... .Pg ..... Body Tracking................. .Pg 25 Body Tracking for Imagery.. .Pg 25 Hardware/LEDware Overview.. .Pg 26 Graphical Marionettes/Scrip ting by Enactment............... .....0 .................. Pg30 Signing as Computer Input .Pg Concept............ -Pg 37 34 Pg38 Conclusion..... ...................................--- Pg 39 Illustrations.. ............................................ Pg 46 ... .----- References..... ....................... Section II Appendix............... .. General Comparison.. . Pg - -. . .- . . . . . . . . . . . 52 Pg 52 ... Op-Eye.............. .Pg56 Watsmart............ .Pg59 Bibliography........... .Pg61 iv Section I V Introduction The interactive bridge cannot be reasoned with, cannot be communicated with in human terms, and by its very is nature It is a link, capable only of repetitive rigid responses. location between two situations. An Interface is a surface a regarded as the common boundary of two bodies or spaces. It is the study of these bonded bodies or spaces that enables us to understand what happens to each when they interact. We use our sensory impressions that reach us from the external spatial world surrounding us to construct the mental model of our universe. This includes all that we think, same that we create. Human output spawns from the sensory pool. universal It is this pool of human perception that that relationships together relatively un-associated. at appear, first all ties encounter, With this raw material we compile, associate and communicate. Our most identifiable source for locating our physical second is the beings psychic in a self-identification spatial understanding Page 1 of context. that is The context. Physical constituents which link us to another person, object or idea, are not, in and of themselves, interactive, merely the structural bond or surface interface. the passage of the creative psyche create what we have come to know Page 2 across as The this Human but It requires bridge to Interface. Defining 3D Space Physical Computer Space The spatial qualities of a computer begin with the system itself. of electrons boards inserted slots into machine. the of on rows in placed clippers, and signal boosters, resistors, of banks through flow Internal law. machine and, as such, cannot violate natural rivers embodied physically a The computer is, of course, Memory is bit of organized as a system of cells which represents each data points. There can be no space word has a number associated with it, memory in byte or every machines, In most The matter. without machine not only occupies space, but also formats even geometric patterns. discrete of data, making computer space ultimately composed circuit which is called of as a its address. thought Computer memory can also be The randomly accessible and variable information. needed information. In case, either workspace or region of storage that free of its physical or spatial can origins. processor identifies need not know which portion of data it wants, but computer the never It quite is Page 3 is a break therefore only natural to think of a computer as having a logical that has plasticity and dimension. the locate to with a simple vector style coordinate system of bank area Logical Programming Space The addressing, or numbering of as analytical geometry, and is as old centuries. three His space least at Descartes, spatial awoke system numbering from derived is state perception from a bodiless, finite, culturally defined with numbers, and numbers associated with ideas. and terms abstractions, The duality think of computer space requires that a programmer physical associated be Ideas could into the pure extension of idea. both in and pragmatically philosophically. "The computer programmer lives in two worlds simultaneously: his space is a logical entity (like the space of the topologist), and yet it is logically realized in the transistors of storage. it resembles Einstein's In this way... space which is mathematical and abstract claims to be the space of the and still world of experience." <Bolter 84> physical The space of to subject machine. is the terrestrial limitations, yet the logical properties remove it from its mechanical origins. Mathematics, physics, allowed the mechanics of Newtonian put into Euclidean correspondence and Riemannian algebraic with spaces, evaluated in relation to each other terms. numbers in with intertwined geometry numbers. could linear and to be As in then be graphic Mathematical space had become a coordinate system. Page 4 Impressed Graphic Space "Elements of data cannot be manipulated endlessly; they cannot remain forever in the central processor. At sometime, they must be deposited." <Bolter 84> As long as computers use devices such as hardcopy and the cathode-ray tube, they will continue to output all graphics onto the two dimensional world of paper and silvered surface. Here an image is virtually denotated. by the apparent convergence of space Dimension taught to is implied us by the Renaissance masters Piero Della Francesca and Michelangelo. Figure 1. @wpm Page 5 It on is designed this interpolation occurs. <Benton 84> inherent an not Monocular cueing is learned easily function of human optical perception, but is at an early age. optical that surface type The creation of this of impressed exhibition space is the melding of apparent optical depth and human understanding of those laws. the Perhaps genuine spatial vector As in graphics lies, literally, behind the tube. computer 3D of reality or raster scan, the convergence of rays upon the screen emanates from the tube's yoke. from the yoke at the same time as the viewers own ablility to receive and shot Beams of light are dimension as an optical phenomenon. perceive their project the onto to sculptural any obtain reception, when the information will prior time This will be the only surface, meeting and causing a common interface plane. One of the only display devices exploits the potential of 3D graphics is the procedure for acquiring surprisingly simple. the that hologram. The computer from' the data is A display screen can be thought of as a porthole or viewing zone into computer's graphic today available reality. the digitized First, world viewing the of zone the is algorithmically fixed, much like choosing the proper lens for a camera. When this area has been can place computer-defined objects arena. defined, into the the programmer pre-designated This is only one of an infinite number of angles that Page 6 By moving these objects can be viewed from. viewport, and recording dimensionality of new each the space can be tapped. here is instead that consecutive frame in time, all the onto the same piece of emulsion. in the holographic product is of technique is This The animation. each displaying is information This emulsion is technique instead of a real a display or true the perspective, known as "keyframing", and is used often in difference camera the recorded then used object. The that takes advantage of our ability to known as see with two eyes and works on an optical function visual disparity. This is a fine technique for reality. Basically, it is a creating a 3D of a collection reality patterns and process, the latter being capable of artificial of producing, The destroying, and modifying the former <Newell/Simon 82>. most important properties of these patterns are that they can designate objects, process, or other patterns, and they designate process, they can be microcosm unto itself. The question this when that is It interpreted. does is, that' erises a finite interpretation of reality have the same intrinsic capabilities as the world in which we exist? Has of the world within the creator's mind been captured computer process perhaps through universal law? Page 7 some nature the by underlying the and Neurological Representations The instruments that we make are, naturally, extensions of ourselves both physically and psychologically. When using instruments skillfully, we internalize aspects of them in the form of kinesthetic and perceptual habits. they not only modify them, the altering thus of extensions become In sense, perceptions, our basis this of our effective The creation and rendering of relationship to ourselves. artificial reality has not only ornamental significance, symbolic as well. an but We make in our own image and likeness, and holding looking at what we make is like mirror. but we From these representations, internal representations or models in conceptions which continue to alter our up the proverbial modified construct our brains, revise to making approach sense of the world. "The basic idea of cognitive science is that intelligent beings are semantic engines - in other words, automatic formal systems with interpretations under which they consistently make sense." <Haugeland 82> Given this premise, it is then possible to understand the physical correlation between humans and- machines, somehow, it is difficult to accept that a human as a Page 8 yet machine Simply put, we have not yet made is a reasoned principle. a machine that comes anywhere close to bioelectrical potential. The model as human of with people. the In Biology, for sophisticated methods theory compartment reactions where cases conjunction in used is works as model system only when it Machine processes. making decision the in part ourselves better only when we take a conscious act of the computer's understand us helps machine provides open of Open systems are compared with conventional closed systems. systems show contradict the usual quantum leaps in logic. These gaps are often considered to only by explainable life, be the vital characteristics of huge produce they as laws physical to seem which characteristics inherent introducing soul-like or entelechial factors into the organic happening. Artificial intelligence does not have the vital force It. principle directing growth and life. is or in people can be perceived as being irrational A because it systematically claims psychol, a Intelligence misrepresentation is not theory effort only, it Intelligence is not merely a real Software Page 9 is illusion or is creative Without information. best human interface, the computer's illogical be never can computer once Moreover, creativity removed by algorithm to the real thing. behavior to a machine. model a or also String the inherently of life. action. Searcher, which is apparently conceptually but smart, a more than a jukebox, that is, no more than finding matching appropriately. electrical and mechanism outputing no for them Dualism is the concept that mental states are states of the soul, i.e. nature. impulses physically the human's moral and emotional Feelings like anger and elation come from the And the physical manifestation of these emotions is soul interacts with the body. Once again, the laws of physics. Page 10 you how cannot soul. the relax Computer as Artifact We can think of constructed socially memory computer space an as usually that artifact, functions a in predictable ways in order to serve our technological society. Artifacts are almost always less sophisticated than the leading researches of science because they must be built upon In this ornamental and ground that is already intellectually quite simple. sense, electronic space is used for predictable symbolic significance. Figure 2. V 93~~~-- X Y2 Xt X Y1 17U7S 873841831 Y U1 71 74 739 813 V47 K8 ?9 96287i M73874344 M83 M18 V75 ft 136-3 87-1 974 42 M83 06i 9Mt IL 13 O9 474 U738 5688 C4781 Z&28478 9 0743 8404 OM3 oet in? 1825 IM7 6M- U7 482 UK3 M118 18139H 847673 8738 8476 I565MR 228 477 102S SM7 O7UR7 87+1M83 06 01-M 84674 I7M IM7 M Page 11 V71t ag71 We can also see how computer memory has properties that, collectively, can take us back to even more intuitive notions of what an artifact means. For instance, numbers in computer terms are as discrete and corporeal as even a pythagorean of aspects of ancient times would have them. Moreover, all most internal computer space is finite, like the universe in cosmologies. Yet through all the universal attributes, the process and computing is usually experienced a-s a relatively private personal affair. The act of personal intellectual and spatial seclusion. computing It is is during of one of these computer intimacies, that an emotional bonding to the machine occurs. Page 12 Figures 3-5. I Page 13 ) During this bonding period, our bodies along minds, are blended together, and move towards experience of space <Lewin 74>. Here we a with our hodological connect to our machines through sensoral techniques by creating a mental map of our destination. computer as surrounding. object, In this case, as This is a surface, cognitive offers the participant a metaphoric transmission procedures. Figure 6. Page 14 the destination and mapping state as is the philisophical technique of which multi-layered The language through which a machine is selectively opaque; it but allows representing the or exploitation addressing masks of the workspace in which memory is stored becomes virtually transparent. programmer absolute variable subject. is commands an a addresses names The region enigma, In other words, the for for or it physical shell of a computer and its peripherals are designed to be as invisible as possible. Figure 7. Page 15 This duality between opaque and transparent makes a computer workstation a wonderous locale. structure The CRT can become the visible expression of an intellectual or emotional condition while the physical presence of the hardware remains a symbol in and of itself. Figure 8. Page 16 We have physical remaining structure of as a only information. programmed carefully In apparatus display the make to transluscent, conceptual frame for frames become less our time, ourselves outgoing less and obvious, leaving us conscious of only half the icon. But in fact, each aspect of the artifact, the invisible tool and the visible manifestation of that experience of these machines. Page 17 tool, makes up the total Machine Vision Qualitative Considerations Of Machine Vision acquisition the literally, Machine vision, which is, information external to the computer through of sensors, optical is one sensory technique that bridges computer language and the of This type world outside the computer's reality. interface modeling of human behavior, and, instead, uses the acquisition of real, or outside, information, own their helps remove computers from internal producing ultimately machine terms, physical In account of spatial perspective. accurate more a vision helps create a more dynamic or sensitive system. work In only a gross technical analogy does machine vision to focus image, the three-dimensional world, disparity and, perhaps lenses Both use the same as the vertebrate's organs of sight. interpolate to crucial, most the are peripheral to a more important central processing area. But at closer comparison, the We find that there is no machine end similarities technique abruptly. available which accurately simulates the spectacular craftsmanship of the human eye. as The computer has no external associated the eyelids, and eyelashes, to structures screen qualities of light falling on the retina, which in the overall function of "seeing." Page 18 Within such quantities and together, aid the internal function in the overall internal the Within "seeing." of structure of the eye, light converges upon the thin wall of the retina through the fluid vitreous body. device detects multi-layered photosensitive sorting radiation, electro-magnetic neuro-electronic pulsed information. to wavelengths converting and delicate, This Today's machine vision is as process the equipped with no such subtle features, nor is elaborate. The use of photosensitive relatively crudely ground lenses and devices eventually will equipment of finer properties. inadequate with replaced be High quality translators could, to speed in theory, produce machines with sufficient examine dictionaries and that the quantitative factors of refined hardware, sufficient speed and detailed syntactic rules by installing large look-up tables. Many machine vision feel experts sufficient detailed syntactic rules make true machine vision an unrealistic endeavor. Even if a technically equivalent machine vision interpretation could eventually be produced, the machine's the outside reality would, compared to information from external bio-mechanical Though fundamentally remain inadequate. sources, data processed or understood from the context of natural language. peripheral it would its optics, draw still would own of its be internal The computer will never truly understand the difference between synthetic and externally derived data. Page 19 When understands the visual scene in purely syntactic structure, and relates to the exercises its a computer receives optical information, The process in the same linear logic. it machine intelligence in problem-solving by modifying symbol until it produces a structure. solution structures will Solutions therefore remain as represented symbolic constructs. The conclusion is therefore the First, three-fold. creation of realistic simulated worlds is within the reach of a machine's ability. Secondly, the accuracy of artificially an intelligent machine to adequately mirror the world in which Thirdly, optical exist remains that of a heuristic hypothesis. hardware for data acquisition is used when we the simulation or facsimile of real world space is not acceptable. Gesture Analysis People/Machine relationships are empirical kinships the naturally, we expect the computer to become where, extension In turn, we additional compiler for our own bodies and psyche. are, however, also extending the physical space of computer well. raw If the computer could externally obtain the Page 20 from physical graphics. Optical peripherals help the computer literally reach own hardware boundaries making data as the the physical world, there could be a blending of world into the digital reality of computer or machine's out beyond physical its space potentially as large as its field of vision. body tracking, be the performer can In becoming part of the computer, i.e. of the as of thought case the the hardware, but the programmed living machine. actually just not machine, of In this case, the living machine is an extension of both the human's and the sense, it computer's capabilities. a In philosophical certainly is appropriate that machines look to their creators for the acquisition of their data. Computer Constructed Motion An attempt early to as such movement human record This Labanotation used a pictogram method for recording dance. computer was the predecessor to techniques used in simulation today. The Dynamic Technique starts with a simulation of force muscle and the mass which it moves 81>. <Hatze A representation reacts to a pre-designed set of rules addressable by changing programmed variables graphic are that as The product speed and theoretical physical limitations. reality of simulated constructs. such of force, is a The better the constructs the better the simulated reality. Another widely used technique is keyframing. The general packaging of this is to a line line function. Page 21 one Literally commonly simulation frame by called concept frame, interpolation between two pre-defined postures gives the model Used in conjunction with this, analytical movement descriptors such as a route to travel in a predetermined amount of time. Cutting's walking algorithm <Cutting 78> may be used. example, motion is determined by describing fifteen key on a walking figure as a vector-valued oscillation. Figure 9. Page 22 In this points by digitally three-dimensional locations In 1980 movement on film was first grabbing frame by frame to deduce the Highlights found on on key points <O'Rourke 80>. constitute a mapping from object space information <Maxwell 74>. analyzed Pattern as known technique, This positional freedom to subject Recognition, as used in the Moving Light Display technique, was a first attempt to draw raw data from a real world source. The onto the obvious flaw is that once the information is decoded surface of film, all true been stripped away. Its strength the within lies have definitions three-dimensional computers ability to interpret changes in line and two-dimensional form. Computer Controlled Tracking specification the Towards the late 70's research began in all of these techniques use stereoscopic triangulation from a pair of or tracking of articulated motion directly. Almost digitizing devices to determine spatial location. Most of these techniques were in tracking human motion. <Maxwell 82> for developed specifically Now intermediate media such as use film accurate rendering One of these, the Coda-3 System monitors up to 8 landmarks could be bypassed producing a closer, more of the subject. or locations on the body at one time. 3 fan-shaped beams of light across the field of view reflection. Another, the Selspot System Page 23 sweeps Optical scanning uses light to sense emitting diodes worn on the human body to locate each critical limb in a spatial context. The lights are connected to the computer. then picked up by cameras It is from this technique that Op-Eye system for tracking the body was developed. Page 24 The Body Tracking Body Tracking For Imagery human Generally, most three-dimensional systems have been for designed sports biomechanics, neurology and in use are of fields the mechanics. systems research in robotics, tracking digitizing scale current With considered being and displacements within the study of high resolution static attitude in wind tunnel operations. The prime purpose of these researches is to acquire data for the statistical analysis of human motion. The following project uses similar mentioned above with one fundamental difference: body tracking is an imagery-data acquisition tool those as techniques act the which of helps produce an imagery-based product. Optical Body Tracking research is an MIT's Graphical Marionettes Project Ginsburg 83/ Purcell 84/ Lewis 84>. Page 25 of Maxwell 82/ Its prime purpose is the <Bolt creation of trackdata for the animation of figures. project offshoot 81/ computer generated Hardware/LEDware Overview The Op-Eye Body Tracking alternative to the Coda 3 or System Selspot offers providing systems, similar three dimensional coordinate system The suit which has light fabric (LEDware). emitting Each band diodes of diodes position performer (LEDs) a signature pulse which differentiates and locates each free space. Page 26 wears into sewn emits a computer. the to In this case, the system tracks the corresponding the joints (nodes) in the human body. inexpensive an of a the specific limb in Figures 10-11. Page 27 Figures 12-13. Page 28 Optical hardware consists of four two-axis diodes made by United Detectors Technology. detect the position of a spot of light on the tracked LEDs and two-dimensional each detector. Using LEDs and These -sensors its surface. position then obtained via four electrode connections sensors effect lateral Both information at the edge sensitive to is of the infrared range avoids optical interference (optical noise) with existing or ambient light. a camera system that This also avoids the complexity would demand further elaborate of data processing and expense. Figure 14. The sensors do not require precise focus as the detectors sense the centroid of the light spot on its surface. The signals from each detector are fed interface module, Op-Eye, where they are first Page 29 to the central amplified then digitized for processing in a manner compatible with the IBM PC series of micro-processors. Graphical Marionettes/Scripting By Enactment The Tracking Suit is used as motion of the achieving fluid human body. motion an It without analysis and tedious programming. is the alternative the to animator's difficulty The user modeling wears way of motion LEDware create motions that are optically received and stored as within the IBM-PC. A real-time stick figure body is of to files displayed to check continuity. Figure 15. These files can later be filtered and used, in conjunction with larger databases on mainframes, animated sequences.. Page 30 to create more developed Figure 16-17. One long-term project is to create a filing system full of used at trackdata motions much like the cell animation system most animation houses. be stored, The difference is that all motions tree-structure memory for use. fashion, and If the movement of a hand delicate object is needed, the animator Page 31 easily called grasping a goes the to can into small, HAND Directory and for checks names Ideally, there would be a number of back found that can be loaded looked at in the real-time into like different files gra-sping and micro-processor the stick-figure delicate. or Grasp resolution. choice then made, the animator need only call up this With a movement by name, joint or node location, and speed-within the scripting of the animation. Each movement can be used as many times, as many locations, and actually to create speeds the as movement developing a computer animation then cut-and-paste, a more natural form sequence. Figure 18. Page 32 desired again. becomes for without The a creating the process job an of in need of data animated Another possible use for trackdata in total animation system is as an of a 85>. software gives power to certain hierarcical to addition technique called adaptive motion <Zeltzer potential configurations the development of In motion. a environment. the throughout Such examples of other words, automatic can of avoid to object of -the has -any kinematic and behavioral complexities of a person, it might If the better to have help from an example. problem a object collision, information about the physical nature of the If the that detection collision But a object an constraints are currently being implemented in software. in motion is also important. the This object or figure or figure existing within dataland. maneuver process drives certain amount of spatial knowledge can be given to be trained to feedback This that a of, be for example, the performance of joint motion under a certain set of involved conditions exceeds the knowledge base of implemented software, trackdata could help establish the the rules of behavior. Theoretically, the allocation of searching through and finding the appropriate trackdata file could be all done in the task-level of the software. By checking between the motion in software, and the similar trejectories trackdata file, the animation could try to repair an awkward or incorrect motion by altering it with a trackdata alternative. The ultimate goal would be to Page 33 have hierarchical software to guiding-level a few alternatives motion questionable all the offer task-level the having by This motions. making possible the simulation of more complex would be accomplished system the of portions other to that would allocate tasks before the data reaches the scripting or animator-level. Motion and Computer Controlled Tracking lies final product looks. opposite positions. to retain is attempting to Constructed the initial starting are motion simulate the workings of the body while attempts in how natural the Each of these techniques arrive at the same naturalness, but form of motion to begin with the natural polar to best strives of The assumption is is digitally processed. from technique the tracking qualities life Constructed Computer between difference The fundamental to the data as that it it is better a better produce product. Signing As Computer Input Personal computation by definition A goal in developing these systems process. element while enabling the system's mature. should be a private is to retain this interactive capabilities to The use of a gestural glove can help minimize physical inhibition with the hope of seeing interchange. Page 34 a more personalized This Body Tracking tool is geared toward the handicapped as both a learning and a communications been designed to help teach especially those with fine simple and intimate setup. the student motor The enhancer. of Software sign student wears language, by dysfunctions, the has using glove practice hand positions in front of a graphic monitor a to equipped with sensors. Figure 19. A Real-time stick figure representation of position simply mirrors the student's attempts. position closely resembles a letter of the When alphabet stored in the software look-up table, that letter printed on the screen. In this the fashion, or hand's a hand or word word sentences is and paragraphs can be constructed as fast as the student can sign. Page 35 Figures 20-22. Page 36 Concept Series devices are used to a make electrical elements produce These currents and voltages variables of the body and a abstracted. of set behave its Both the that such isomorphically In this human a IMAGE /'IM-IJ/ N 1: A likeness or limitation of a person or thing. 2: A visual counterpart of an object formed by a device (as a mirror or lens). 3: A mental picture or conception; impression, idea, concept. VB 1: To create a representation to bring up before the imagination. Figure 23. Page 37 case, the general "felt" analogy. 2: the and body electronically reflected image is preferred in with element conceptual the qualities. electrical motion. and electronic other model physical relation between physical element explicitly and capacitors, resistors, of of. is its and Conclusion and physical a as Generally, we can think of all we make phychic extension of ourselves. Being the territorial creatures our validate as (such symbolic utilitarian or a bowl cooking aesthetic design, respectively), their function is to we be tools our Whether existences. own more the has obvious logical advantages. The more we make can territories collective and we seem to be, extending personal its and transmit our own nature into our surrounding reality. Computers not only carry the logical formats found but mathamatics, to appear display exclusively to living organisms. We expect attributed been have these machines now, has thinking to exclusively attributed been to also which receive, assimilate, and output correct solutions, until of levels discrete interactive responses which, until now, pure in organisms. We have given them artificial vision, speech, touch, smell, taste, and motor functions. They are able to reproduce their own kind. They have even produced reasonable attempts their between correlations making intelligent internal and our own external worlds. We continue to build these tools image and characteristics that Ironically, simutaneously we have mirror they yet likeness, attribute we given and to true computers transcend existance. Page 38 the in have don't still the qualities. life which attributes logic at of our own Illustrations Figure 1. Mirror Cell Frame from a computer animation. 30 Seconds. Inside a computer three-dimensional surfaces spin in free space. these Reflected from through surfaces rotate, the images the and environment reflected in the surfaces camera. the is the landscape sceen from the viepoint of the camera travels flat environment As flat the are mirrors constantly updated. Figure 2. Data Display Data monitor displaying two separate two-dimensional locations, received by two separate optical sensors. approximately 40 The sensors hertz, are therefore, receiving the screen of sets sets data is of at being refreshed with a new set of data points about once every 30th of a second. This data will be saved into a file later drive objects and figures for animation. Page 39 that will Figure 3-5. Pulsating Orifice 3 frames from a computer animation 5 Second loop The wall of the animated orifice is driven by scripted software. Each individual 'clot' rotates in X and their own origins. The location camera receives its Y around from trackdata. The trackdata was created by the author by placing her chest against the face of a monitor located next to optical sensors. The final product is a kenetic wall of red polygons and a camera that in the heaves into the space middle, and then out. Figure 6. Computer Pulsed Island. detail, computer installation Orifice Animation on a gold-leaf monitor reflects onto the chest of a stylized women's body. Page 40 Figure 7. Computer Pulsed Island detail, computer installation Computers painted red, black and white, sit on of white sand. Graphics which pulse from the an center island of the screen outwards, change from black to red, and back again. Figure 8. Computer Pulsed Island computer installation . White monitor in foreground displays a of a women's body which echos features from stylised body towards the left, and beneath it. Page 41 the digitized. both pure picture the white black sand Figure 9. Stick Figures Two overlayed frames from a test animation. Figure 10. Model in LEDware Collecting upper body trackdata for Marching Band Animation. Figure 11. Model in LEDware Collecting upper and lower body trackdata archives. Figure 12-13. Dancer in LEDware Collecting upper and lower body trackdata for animation. Page 42 Figure 14. Model in LEDware Checking stick-figure for continuity of motion.. Figure 15. Stick figure in pieces Real-time stick figure is separated into four sections. The top two squares are what each seperate sensor is tracking from the uppper body. The lower two squares are what they are tracking of the legs. Figure 16. Frame from Marching Band Animation 20 seconds Each of the animated band members trackdata in the scripting level. Page 43 were assembled from Figure 17. Frame from Eggman Animation Eggman was assembled from trackdata in the scripting level, and then produced through the keyframing technique. Figure 18. Frame from Cloudpeople Cell animation 30 seconds Both software and trackdata driven figures share this animated space where gravity is non-existant. Figure 19. LEDware/Glove There are 15 critical joints in the human hand. Each joint has an associated strip of LEDs sewn into the glove. Page 44 Figure 20-22. From real-world to dataland The individual nodes of the hand are tracked and displayed on the screen with or without the connecting lines. From this information alone, the modeling of a more refined hand can be executed. Figure 23. Electronic window Page 45 References <Bolter 84> D.J. Bolter Turings Man: Western Culture In The Computer Age Carolina Press 1984 pg 97 <Bolter 84> D.J. Bolter IBID 1984 pg 81 <Benton 84> S. Benton Lecture, MIT 1984 <Newell/Simon 82> A. Newell and H.A. Simon Computer Science as Empirical Inquiry Mind Design MIT Press 1982 Page 46 <Havgeland 82> J. Havgeland Semantic Engines Mind Design MIT Press 1982 <Lewin 84> K. Lewin Space Newtworks: Towards a Hodological Space Design Man, Starting with a Cognitive/Perceptual notation PHD Thesis, Mit Mitropoulos, University of Edinburgh 1974 <Hatze 81> H. Hatze Musocybernetic Control Models of Skeletal Muscle University of South Africa Press 1981 Page 47 for Urban <Cutting 78> J. E. Cutting Behavior Research Methods and Instrumentations 10(1):91-94 1978 <O'Rourke 80> J. O'Rourke Image Analysis of Human Motion PHD Thesis, University Of Pennsylvania 1980 <Maxwell 82> D. Maxwell Graphical Marrionette: Master Thesis, A Modern Day Pinocchio MIT 1982 <Bolt 81> R. Bolt Proposal for the Development of a Graphical Marrionette Techinical Report, MIT Architecture Machine Group 1981 Page 48 <Ginsburg 83> C. Ginsburg Human Body Motion as Input to an Animated Graphical Display Master Thesis, MIT 1983 <Purcell 84> P. Purcell Graphical Marionettes Project Progress Report to NHK Corporation 1984 <Lewis 84> J. Lewis Computer Animation of Human Figures in Conversation and Action Master Thesis, MIT 1984 Page 49 <Zeltzer> D. Zeltzer Towards an Integrated View of 3D Paper for AMT, Computer Animation MIT 1985 Page 50 Section II Page 51 Appendix General Comparison The following is a comparative evaluation between the existing Op-Eye Tracking System (MIT), and The WATSMART Spatial Motion Analysis and Recording Technique available from Northern Digital, Waterloo, Ontario. The method of systems are quite similar as observed in operation difference lies within technique is making how clearer both non-contact devices. controlled the trackdata The data files. 3D important acquisition Is it upgrading existing Body Tracking hardware and software, it advantageous both the general f'unctional overviews below. Fundamentally, they are digitizing, state of the art tracking for worth or to buy into a pre-existing package such as is the WATSMART. Good trackdata is a function of proper triggering and synchronization within the data collection technique. What has been overlooked with the current system is the importance camera setup and proper hardware calibration. Whenever Page 52 one of or the system must have more cameras/s-ensors are physically moved, the proper facilities constructs. There is the OP-Eye system. automatically by to camera program calibration cameras tubular steel all of view in frame containing 22 pre-surveyed LED markers run. to provided with the system and takes only a few minutes The alignment procedure requires the placing of a done is registration the Watsmart by use of a with existing no such updating technique This mathematical 3D its reconstruct in use. The calibration file produced by this procedure must be used as an input to all data collected by . This calibration and is conceivable to the 3D linear transform process for that particular camera setup. technique was considered for the though, some extent. There is, Op-eye, major one drawback. There are already too many arbitrary hardware devices it virtually built into the system, which makes traditional and installation. Existing trackdata critical files and has to be low-passed filtered no any to are, These optic extremely is to such excess that the product is not accurate for analysis and barely acceptable use in animation. The final evaluation must be made Page 53 lab only therefore, accurate for gross motor functions. The raw data noisy were accuracy. standards established for relative/absolute are to there correctly calibrate. In its initial conception standards impossible by for direct 0 comparison of trackdata made from each system. The Watsmart also includes software accuracy for modeling purposes. It to is increase easy to the obtain pitch, and roll of models as well as compute valid 3D 3D yaw, data in situations where there are few or no markers within common view of at least two cameras. This is extremely important, for visual obscurity is one of the prime reasons for excess optical noise in the current system. Unfortunatly, all optical tracking devices have the similar problem of background lighting and reflections. Many surfaces that appear as black in visible wavelengths are actually quite reflective in the near infrared light red region. Care must be taken in setting up an in experiment so that position to reflect directly from markers all surfaces a into anti-reflective. Unobvious problems occur' because camera the are camera receives both the true marker optical signal and its reflection at the same time causing an apparent position measured. This is due to the shift fact in the marker that the camera averages all infrared light it sees, and therefore a reflection cannot be separated out from the objective image. The Op-Eye Package was constructed over Page 54 a period of two years. All standards technical featured The the in specifications obtained Machine Group, specifications in lab are owner's manual findings of and the actual Architecture MIT. Watsmart is a total specifications are averages between package. All standards featured preliminary technical description manual and The Center between averages for Bioelectrical Engineering, MIT. Page 55 the technical in findings a of Op-Eye Package Hardware 1) 4 bi-lateral effect diode cameras 2) LEDware 3) A camera controller and power chasis 4) - 5) A computer and controller board 6) - 7) Adequate cables to interconnect all the above Software 1) - 2) Define the number of nodes and their location 3) Datacollection and storage of raw data 4) Raw data to 3D information using 3D linear tecniques 5) Produce 2D stick figure graphics 6) - Page 56 transformation Op-Eye Package Technical Specifications A/D Resolution: 12 bit. 1 part in 4096 Spectral Range: 350-1100 nano meters Approximate Saturation Level: lOmW/cm2 Typical Position Linearity: 0.5% in central 25% of detector/ 3% in central 75% of detector Minimum Detectable Intensity at Detector Surface: (10 to the 7th ohms) 2uW =10v (full scale) Programmble Gains 1,10,100,500 Page 57 High gain Watsmart Package Hardware 1) One or more high resolution infrared cameras 2) Variety of infrared diodes (IRED) 3) Camera controller and power chasis 4) Marker strobing controllers (8 markers each) 5) A computer and controller board 6) A pre-surveyed calibration frame to facilitate quick camera setup and ensure positional accuracy 7) Adequate cables to interconnect all the above Software 1) 3D re-construction/calibration used when the sensors are moved 2) Parameter software to define an experiment in terms of the number of markers used, the frequency (frame rate) of data collection, duration of collection, etc. 3) Data collection and disk storage 4) 3D linear transformation software that changes raw data to a more useable 3D format. Page 58 Watsmart Package Software (Cont.) 5)Produces 2D stick figure graphics in real time 6) Perform general functions such as Butterworth of Spline filtering, velocity and acceleration derivation and graphical examination of both data and its derivatives. Technical Specifications Camera resolution: 1:406 or 0.00025 of field Absolute accuracy: Corrected to 0.002 of full range (optional to .00025) Field of view:35 degrees w/ supplied 22 mm custom lens (vert. and hor.) 45 degree diagonal angle. Optional 90 degree diagonal custon lens. Distance: .75 to 10 meters, dependent on emission power if LED marker .Sensitivity: Infrared light in spectrum.range 800 nanometers to 1050 Aggregate max.sampling rate: 8,000 markers/second/camera Page 59 Op-Eye Optional Position Indicator United Detector Technology 3939 Landmark Street Culver City, Ca. 90230 (213) 240-2250 Watsmart Spatial Motion Analysis and Recording Technique Northern Digital 415 Phillip Street Waterloo, Ontario N2L3X2 (519) 884-5142 Page 60 Bibliography Badler, N., "Digital Representations Of and Smoliar, S., Movement", Computing Sureys, Vol. 11, No. 1, March Human 1979, pp19-38. Baker, Kenneth(editor), Brave New World?. Pergamon Press, 1982. Elmsford, N.Y., Bet-telheim, Bruno. The Empty Fortress: Infantile Autism amd the Birth of the Self. The Free Press, New York, 1967. Bolt, Spatial Data-Management. Technical Report, MIT Richard A. Architecture Machine Group, March, 1979. Bolt, Richard For "Proposal A. The Graphical Marionette". Technical Report. MIT Architecture Machine Group Report, 1981 Bolt, Richard A. The Human Interface, Where Computers Meet. Lifetime Learning Publications, A Wadsworth, Inc., Belmont Ca., 1984. Page 61 People Division And Of Bolter, David J. Turing's Man: Western Culture In The Press, University Of North Carolina Age. Computer Hill, Chapel N.C.. 1984. the Computer State. Vintage Books, A Burham, David. The Rise Of Division Of Random House. Cutting, J.E. "A New York, 1984. Program to Generate Dynamic Point-light Displays". Behavior Synthetic Methods Research as Walkers and Instrumentation 10(1):91-94, 1978. Danzinger, James N., L. Williams H. Dutton. Rob Kling, and Kenneth Kraemer. Computers And Politics: High Technology Local Governments. New York: Dechert, Charles R. The in American Columbia University Press, 1981. Social Impact Of Cybernetics. University Of Notre Dame Press. London 1966. De Fleur, Melvin L., and Ball-Rokeach, Sandra. Theories Of Mass Communications. New York, New York: Logman Inc., Page 62 1982. Dertouzos, Michael L., and Joel Moses. The Computer Age: A Twenty-year View. Cambridge, Ma.: MIT Press. 1979. The Evans Christopher, Micro Millennium. New York: Viking Press, 1979. Federal Information Issued By The Sources And Systems Sourcebook Series. Washington, D.C., Inc. Berkley, Ca., Fink, D. G. Doubleday Co., A Directory Congressional 1980. Confessions Of An Infomaniac. Sybex 1984. Computers Inc. 1980 General. Comptroller Ferrarini, Elizabeth M., 1980, And The Human Garden City, N.J. Ginsberg, Carol. "Human Body as Anchor Books, 1966. Imput Display". Master Thesis, MIT. May, 1983. Page 63 Mind. To Animate Graphical Goethals, T. Gregor. The TV Ritual. Universalist Association. Beacon Press Books, 1981. Hatz, H., Mycrocybernetic Control Models of Skeletal Muscle. University Of South Africa Press, 1981 Haugeland, John. Mind Design. MIT Press, Cambrige, Ma. 1981. Higgins, Joseph R. C.V. Human Movement: An Intergrated Approach. The Mosby Company, St. Louis, Mo., Hutchinson, A. Labanotation: The 1977. System Of Analyzing And Recording Movement. London, 1954. Hulteen, Eric Andrew. "The Human Interface To Personal Computers". Master Thesis, MIT, June, 1980. Kidder, Tracy. The Soul Of A New Machine. 1981. Page 64 Avon Books, N.Y.C. Krippendorff, Klaus. And Communication N.Y., N.Y., Gordon And Breach Science Publishers, In Control 1979. Notation. Movement Laban, Rudolf von. Principles Of Dance And Society. Bristol, Great Britan: J.W. Arrowsmith Ltd. 1975. Lewis, "Computer John. Figures Human of Animation in Conversation and Action". Masters Thesis, MIT, June, 1984. Maxwell, Marionette: "Graphical Delle. Rae A Modern Day Pinocchio". Master Thesis, MIT, June, 1983. Mitropoulos, Space Efitmos G. Cognitive/Perceptual Notation". PhD Towards Hodologocal With A University of Starting Man, Urban For Design Networks: "Space Thesis, Edinburgh, 1974. Andrew Negroponte, Nicholas and Lippman, "Transmission Cybernetics Of Presence". Technology A proposal Division, Defense and Bolt, submitted Advanced Richard. to Research Projects Agency. The Architecture Machine Group, MIT, 1983. Page 65 the Nora; Simon, Cambridge, O'Rourke, Ma.: MIT Press, J. Of Computerization The and Alain Minc. Society. 1980. Image "Analysis Of Motion". Human PHD Thesis, University Of Pennsylvania, 1980. Pheiffer, John. The Thinking Machine. J.B. Lippincott Co. Phildelphia, 1962. Purcell, Patrick. "Graphical Report To NHK Corporation". Project: Marionettes Architecture Machine Progress Group, MIT Cambrige Ma., Febuary, 1984. Roberts, Shelly. I'm Sorry, But I Don't Speak Hexidecimal. Write Protect Publishing. New York, NY. 1985. Rose, Frank. "Wired To God: Accolytes Of High Fair, August 1984, Volume 47 Number 8, pg. 40. Page 66 Tech". Vanity Rybczynski, Witold. Taming The Tiger: A Struggle To Control Technology. Viking Penguin Inc. N.Y.C. 1983. Smith, Brian Reffin. Soft Art Computing: And Design. Addison-Wesley Publishing Company, Workingham, England, 1984. Sussman, Lenard R. "Glossary For International Communications". The Media Institute, Washingtion D.C., 1983. Turkle, Sherry. The Second Self Computers And The Human Spirit. Simon And Schuster, N.Y.C., 1984 Weiner, Norbert. The Human Use Of Human Beings: Cybernetics And Society. Garden City, N.J.: Doubleday, 1954. Winner, Langdon. "Mythinformation: Romantic Computer Revolution". A paper delivered Technology Department, U.C. Santa Cruz. Page 67 In The Politics And Politics to. the Zeltzer, David. "3D Movement Simulation", Siggraph 1982 Tutorial, July 1982. Zeltzer, David. "Towards and Integrated Animation", Paper Delivered for AMT, MIT. Page 68 View of 3D Computer September 1985.