Localization of Sound in Micro-Gravity

Samidh Chakrabarti Ra Krikorian Sharmila Singh Boris Zbarsky January 29, 1999

This team is applying to y on the second Spring of 1999 slot because it coincides with MIT's spring break.

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Contents1 Abstract 2 Overview2.1 2.2 2.3 2.4 2.5 Sound Localization Mechanism . . . . . . . . . . . Possible E ects of Micro-gravity . . . . . . . . . . Existing Research . . . . . . . . . . . . . . . . . . . Binaural sound . . . . . . . . . . . . . . . . . . . . Bene ts of Localization Research in Micro-gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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3 Objectives and Hypothesis 4 Test Description 5 Equipment

4.1 Localization Precision Tests (Tests P-H and P-V) . . . . . . . . . 9 4.2 Localization Accuracy Tests (Tests A-H and A-V) . . . . . . . . 10 4.3 Summary of Possible Tests . . . . . . . . . . . . . . . . . . . . . 10 5.1 Laptop Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.2 Stereo Headphones . . . . . . . . . . . . . . . . . . . . . . . . . . 11

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6 Load Analysis

6.1 Structural . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6.2 Electrical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

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7 In- ight Testing Procedures 8 Data Acquisition System 9 Test Operating Limits 10 Data Analysis 11 Proposed Manifest 12 Photographic Requirements 13 Hazard Analysis 14 Student Team 15 Outreach Program 16 Journalist 17 Scheduling2

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18 Project Support 19 Budget 20 Summary 21 References A Appendix I - BiosA.1 A.2 A.3 A.4

Samidh Chakrabarti Ra Krikorian . . . Sharmila Singh . . . Boris Zbarsky . . . .

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B Appendix II - Student Advisors

B.1 Col. Peter Young . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 B.2 Professor Dava Newman . . . . . . . . . . . . . . . . . . . . . . . 19

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1 AbstractHuman beings have the ability to localize sound { if presented with a tone from a certain direction, the human head processes the information needed to nd and identify the sound source. What is not known is whether or not this ability to localize sound is gravity dependent. What happens when a human is asked to localize these sounds without the gravity cue of a "de nite down"? We propose to non-invasively test the human ability to localize sound in micro-gravity by using binaural sound techniques. This type of research is important for the design of both space habitats that can reduce disorientation through the use of strategically placed sound cues and the development of accurate micro-gravity simulations.

2 OverviewPerhaps the most common sensation that astronauts immediately experience in micro-gravity is severe disorientation. Often this sensory "confusion" leads to space sickness or space adaptation syndrome. Since sound localization is a critical skill that astronauts use to regain their bearings, careful study of sound localization in the micro-gravity environment is required. A better understanding of directional hearing may yield new insights into space sickness and aid in the design of spacecraft, space communication systems, and earth-bound space simulators.

2.1 Sound Localization Mechanism

Sound localization is a complex computational task that the brain performs with apparent ease. The brain uses a combination of interaural, monaural and dynamic clues to determine the location of a sound. When a sound wave hits the head, it is picked up by one ear. Then the head itself distorts the sound wave, and the distorted wave is picked up by the second ear. The distortion introduced by the head is uniquely determined by the incident angle of the incoming wave. Early in development, the brain learns to compute the di erences between the two waves processed by the ears and uses this information to determine sound location. In e ect, the brain creates a head-related transfer function (HRTF) which describes the relationship between sound waves received by the two ears as a function of the sound's origin. Since the topology of every head is unique, each person uses a di erent HRTF. When a person hears a sound, each ear transduces a sound wave into an electrical impulse which is sent to the brain for processing. The brain analyzes the two waves and computes the inverse function of the HRTF to precisely determine the sound's origin. Figure 1 elucidates the concepts behind the HRTF. Part (b) shows how a sound impulse from a distant speaker registers as two di erent sound waves by each ear. The transformation of one wave to the other is given by the HRTF. 4

Figure 1: Natural Hearing and Simulated Natural Hearing using the HRTF Part (a) shows that a conventional headphone system doesn't reproduce this e ect, while the playback system in Part (c) demonstrates that signal processing techniques that alter a sound wave according to the HRTF can be used to simulate natural spatial hearing. In addition to the interaural clues derived from the HRTF, each ear has tools to help determine sound location. The crevices, folds and contours of the outer ear, shown in Figure 2, re ect sound waves in di erent directions as a function of frequency and incident direction. If an identical sound is played from two di erent spatial locations, it will generate two di erent spectral histograms because frequencies are di erentially ampli ed by the folds of the outer ear depending on their original location. Another monaural clue that each ear can use is the echo time delay sounds produce as they re ect o of the physical environment. Given the echo delay time and visual knowledge of the environment, the brain can narrow down the possible locations that a sound could have originated from. Finally, head motion can drastically improve the accuracy of sound localization. By gathering multiple sets of sound data corresponding to various head positions, the brain can both interpolate and triangulate the location of a sound. Humans use this trick constantly as a means of identifying whether a sound is coming from the front or back, since most interaural and monaural clues do not help in answering this question.

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Figure 2: Structures of the outer ear

In micro-gravity, a host of physiological changes a ict the body. One of the most fundamental physiological changes is the increase of blood ow to the brain. How exactly brain function is a ected by this increase in blood is far from understood. Hearing is doubly a ected by micro-gravity: in addition to brain blood ow increases, uids in the inner ear are disturbed. It is entirely likely that these conditions could cripple the brain's ability to accurately judge sound direction through a mechanism such as interference with the computation of the HRTF. Early research by Soviet scientists showed that sound localization accuracy could drop by as much as thirty percent after prolonged muscle inactivity and increased blood ow to the head (such conditions are present in micro-gravity). The Soviets collected this data by con ning test subjects to bed for prolonged periods of time, and then taking measurements. Before more detailed research can be described, it is necessary to understand the conventions governing the auditory spatial coordinate system. Figure 3 illustrates the three orthogonal planes that de ne the coordinate system. The horizontal plane is the one that is parallel to the ground when standing (it contains the eyes and the ears). The median plane contains our body's vertical 6

2.2 Possible E ects of Micro-gravity

2.3 Existing Research

Figure 3: Spatial hearing coordinate system plane of symmetry. The frontal plane is mutually orthogonal to the other two planes and intersects them at the center of the head. is the angle from forward in the horizontal plane, while is the angle to the horizontal plane. In 1991, a joint Austrian-Soviet experiment on the Mir space station called AUDIMIR tested a cosmonaut's ability to accurately localize sounds. The AUDIMIR test suite was designed to determine how precisely a cosmonaut could auditorily determine the forward direction ( = 0, = 0). AUDIMIR results demonstrate that although spatial hearing in micro-gravity is largely una ected in the horizontal plane, sound localization in the medial plane is shifted ten degrees downwards. In other words, the cosmonaut test subject thought that sounds came from ten degrees lower ( = 10 ) than where they actually did. In addition, the AUDIMIR experimenters tried to determine if directional hearing becomes a more important sense in micro-gravity than in one-G. They hypothesized that if sound localization were more important in micro-gravity, then it would be easier to "trick" a cosmonaut into feeling a sense of motion due to hearing a moving sound source. AUDIMIR showed that a counterclockwise rotating sound source (varying ) could in fact mislead the human mind into thinking it was spinning clockwise. However, whether the illusion of motion was greater in micro-gravity than under normal gravity conditions is still unclear. The primary shortcomings of the AUDIMIR research that we aim to address are the use of only one test subject and the testing of localization ability around only the forward direction. Our tests will employ multiple test subjects and test sound localization in directions other than forward, such as = 45 or 45 while in the horizontal plane.

2.4 Binaural sound

In order to simulate spatial sound for this proposal without going to elaborate means, binaural sound is played for the test subjects. Binaural sound is a 7

Figure 4: Recording sound in binaural format technique to create spatial audio (three dimensional instead of the traditional left and right) using only a simple set of stereo headphones. Stereo sound is usually recorded with two or more microphones { each microphone is mounted to listen to a separate part that the recorder wants noted. These sounds are then mixed together and edited to be emitted from two separate channels. Because of this, stereo sound requires two loudspeakers and an in nite number of channels to produce a perfect recording. Binaural sound recordings take the recording situation and make it a little more realistic by closely mimicking how the human body listens. Binaural recordings are usually done with two omnidirectional microphones mounted at the entrance to the ear canals on an arti cial head (see Figure 4). This arti cial head has the microphones mounted 6 to 8 inches apart, and may even have an equivalent of the eshy ridges of the outer ears to modify the frequency balance of sounds depending on the direction (relative to the head) in which they originate. This head is placed wherever the recorded wishes the listener to be placed while listening. If these two channels of recording are kept completely separate, then fed back to a human head directly through headphones, the sound will exhibit the same spatial properties that the recording head experienced, thereby giving the human the illusion of spatial sound.

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Although little research has been conducted on the e ects of micro-gravity on hearing, this information could be invaluable in a variety of applications. Medically, it could help to unravel how the human body becomes so disoriented in micro-gravity as to experience space sickness. Also, more realistic simulators that incorporate the audio localization distortions due to micro-gravity could be built to better train astronauts. As a nal example, spacecraft and space station designers could carefully select the locations of sound-producing equipment to create a "sound landscape" that itself provides orientation clues. Even if it is found that sound localization is not impaired in micro-gravity, this research could still be bene cial. Since the senses of touch and sight are readily confused by weightlessness, perhaps sound localization grows to prominence as a tool for assessing orientation in micro-gravity. In this manner, sound clues could be used to help astronauts regain their orientation in micro-gravity more quickly.

2.5 Bene ts of Localization Research in Micro-gravity

3 Objectives and HypothesisThis experiment attempts to nd out exactly what e ect a micro-gravity environment has on the human body's ability to localize sound in the horizontal and vertical plane as related to the head. We expect there to be no change in the horizontal plane as that does not require an up or down cue { but we do expect the vertical tests to show that the ability to localize sound diminishes since there is no aid for an absolute up or down given by gravity.

4 Test DescriptionThe subject's ability to localize sound (with respect to both precision and accuracy) will be tested at 5 widely separated locations in the plane of the head. These will be at = 0 , 45 , 135 , 135 , and 45 with = 0 (see Figure 5 for diagram of test loci). Each experimenter will be able to run his or her own experiment, thereby allowing two simultaneous experiments to occur on the KC-135a. Four di erent kinds of tests can be performed at each test location. Two of the sets will determine the absolute accuracy of the localization ability (called Test A-H and Test A-V) and two of the tests will determine the resolution (precision) of the localization ability (called Test P-H and Test P-V). Within each set, one type of test will try to determine the localization ability in the horizontal plane (A-H and P-H) and the other type will focus on the vertical plane (A-V and P-V).

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Figure 5: Proposed testing loci

These tests will elucidate how precisely a subject can discern changes in a sound's location. The subject will continuously be presented with a reference tone for a location { a tone located precisely at that spot (see Figure 5 for test loci). For test P-V, the subject will be presented with a series of tones with the same azimuthal location (stationary ) as the reference tone but di erent polar locations (varying ). For each of these, the subject will have to judge whether the tone is above or below the plane of their head. The subject will indicate her response by pressing a designated key on a laptop keyboard. The responses the subject makes will be recorded by the computer and used to determine the next tone in the tone sequence. When the subject answers correctly, she will be presented with another tone that is closer to the reference location. If she answers incorrectly, she will be presented with a tone further from the reference location. In this fashion, the subject's ability to localize tones in the polar direction can be determined. Test P-H will be conducted in a nearly identical fashion, except the test tones will be stationary in altitude ( xed ) and vary in azimuth (varying ). In this manner, we will be able to determine the subject's overall sound localization resolution ability (in degrees). Note that all tones will be presented to the subject by using pre-recorded binaural sounds stored in MPEG les and played by the laptop. Originally, it was thought that a control on visual distractions the subject will be asked to close her eyes during all of the tests (the idea to blindfold the subject was rejected immediately due to safety concerns). Unfortunately this is extremely unsafe { to modify this, the subject will be asked to focus on the laptop computer and attempt to ignore all other visual distractions. The reporter will also be asked to \spot" the subjects and prevent them from making a dangerous fall. 10

4.1 Localization Precision Tests (Tests P-H and P-V)

These tests will attempt to discern how absolute sound localization accuracy is a ected in micro-gravity. In other words, how accurately a subject can determine where exactly a sound is coming from. Test A-H is identical to test P-H, except there will be no reference tone presented; instead, the subject will be told by the computer where the target location is. Test A-V is identical to test P-V, except there will be no reference tone; the subject will be told by the computer where the target location is. This strategy will enable us to pinpoint where the test subject perceives a sound loci to be (not necessarily where it actually is).

4.2 Localization Accuracy Tests (Tests A-H and A-V)

4.3 Summary of Possible TestsTest Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Test Location =0 , =0 =0 , =0 =0 , =0 =0 , =0 = 0 , = 45 = 0 , = 45 = 0 , = 45 = 0 , = 45 = 0 , = 135 = 0 , = 135 = 0 , = 135 = 0 , = 135 = 0 , = 45 = 0 , = 45 = 0 , = 45 = 0 , = 45

Test Type A-H A-V P-H P-V A-H A-V P-H P-V P-H P-V P-H P-V A-H A-V P-H P-V

Each test will be performed multiple times by di erent subjects in zero-G, and 1-G (all in the airplane, as a control). We chose this testing suite because it gives us a broad picture of the human ability to localize sound (both accuracy and precision) across a large portion of the auditory eld. The type A tests will not be conducted for sounds coming from "behind" the head, because spatial hearing tests have shown that the human sound localization ability for these regions is extremely poor, hence accuracy data would not be reliable. We believe our testing procedure will produce better statistical results than those from MIR since we are testing more than just the horizontal plane and the vertical plane at 0 from the front of the human head. We believe that by asking the subject to localize sound in the vertical plane at = 45 , 135 , 135 , and 45 we will get better data than AUDIMIR.

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5 Equipment

5.1 Laptop Computer

Two laptop computers are going to need to be brought on the airplane for testing purposes { one for each experimenter. Each will already have pre-recorded binaural sounds for each possible position that we may be testing. Outputting the sound from the laptop will be a custom piece of software written exclusively for this test { the testing software will perform the test on the human operator as described in the above section. To hear the sounds being presented by the testing program, two pairs of high quality stereo headphones will be brought aboard. These headphones will be the ear covering type so as to provide some immunity from ambient noise (another control) and some safety to the human using them (headphones that require one to have the ear piece inserted and held by the ear seems too dangerous to use in the chaotic environment inside the KC-135a).

5.2 Stereo Headphones

6 Load AnalysisThe laptops and headphones together weigh approximately 10 pounds. During the ight the laptops will remain velcroed and duct taped to the oor of the KC-135a with its screen closed. The reason the screen is not kept open for the duration of the ight is because there is a concern that the screen of the laptop will start to hinge violently during the micro-gravity to hyper-gravity uxations. The \sleep" mode will be disabled during the ight so we can run the laptops with their covers closed. However, we will have to secure them in a fashion so in the worst case that we need to see the computer's screen, we will be able to raise it easily. Both the laptop and the headphones will have no problem surviving the take o and landing. The Apple G3 Powerbooks that we are using have been used on airplanes in many di erent situations and will be able to survive the 2G pullup. The headphones we are using (it has not been con rmed exactly which headphones we will be using) will also survive the stresses of the cabin as they were actually designed to be used on an airplane. Both laptop computers, and both sets of headphones will be powered by their own internal battery supplies, requiring no external electrical supply.

6.1 Structural

6.2 Electrical

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7 In- ight Testing Procedures1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. Unpack equipment Place headphones on Plug headphones into the headphone jack on the laptop Turn on the laptop Start the testing program (either by double clicking on the icon, or typing the command at the command prompt) Lift oneself o the surface so there is no tactile contact with the oor If a type P test, listen to the reference tone presented by the computer. If a type A test, listen to a verbal description (a voice sound recorded on the computer) of the target location. Listen to the testing tone Indicate by pressing a speci ed button whether or not the testing tone is above or below the reference position (if a type X-V test) or right or left of the reference position (if a type X-H) test. Repeat 6-10 until the computer has determined the tester's ability to localize in that plane. The computer will randomly pick another test to work on. A single test should take no longer than 20 seconds. Terminate program Shutdown computer Unplug headphones Store equipment

The rst step is obviously to set up the experiment. This involves unpacking the equipment, turning on the laptop, donning the headphones, and then starting the testing program. When micro-gravity starts, the tester rst needs to lift him or herself o the oor so there is no tactile contact with it, and second start the testing loop going; pausing it for the hyper-gravity pull ups (we are not testing during the pull up, so putting the laptop's testing loop on pause will allow us to resume the micro-gravity testing). The tester can then perform the test as outlined in test description section, and in the outline above.

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8 Data Acquisition SystemAll data is going to be recorded by the laptops. The testing program will be dumping a data le outlining each di erent test and all the pertinent data while it is testing the tester. The data le will contain everything of interest { the reference position, the testing position presented, the human response to the testing position, and the delay in time of the presentation of the tone and the human response to it. All this data can then be printed into hardcopy form for safe keeping once the subject is on the ground.

9 Test Operating LimitsThis test will only be tested in the micro-gravity environment that the KC-135 provides, and not during the hyper-gravity pull up. As for the minimum or maximum amount of parabolas, there are no hard set numbers. The amount of parabolas is tied directly to how statistically accurate our results are { so the more parabolas, the better for us.

10 Data AnalysisThe data from this experiment will be compared to both control data (taken at Earth gravity) and the data from the MIR experiment. Only data from the = 0 position will be compared to MIR. In all cases, the Mann-Whitney U-test will be used to determine whether there is a statistically signi cant di erence between the data sets, with the most accurate localization achieved in each trial being the comparison variable. In addition, data from di erent test subjects will be similarly compared to identify statistically signi cant individual variations, if any. Data from di erent angles will also be compared to identify anisotropies in localization ability. It should also be taken into account that subjects may become too motion sick to perform a complete set of experiements. However, much of the experiement is redundant so if the 4 testers can complete portions the run, then there should be enough data for statistical analysis.

11 Proposed Manifest2 Laptops 2 sets of stereo headphones

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12 Photographic RequirementsThere are no inherent photographic requirements for this experiment. Presumably the journalist will be bringing photographic equipment aboard { but that is not directly related to this experiment.

13 Hazard AnalysisDue to the small amount of equipment necessary for this experiment, there are not many hazards to consider. The one that is of concern is the scenario of an unexpected high acceleration. Since laptops are inherently fragile, the only precaution we could take is to require the tester to not drift too far from the oor. The laptops will be velcro fastened to the oor, however, to prevent them from damage (the experimenter will be oating above the laptop while the laptop remains fastened to the oor). The only other hazard of concern is the production of an extremely high volume sound from the headphones { but to alleviate this problem, the maximum gain on the volume will be hand adjusted and locked into position so the sound will be dampened. Electrical shock is not of concern as the laptops are insulated and are designed to be brought through many di erent types of stress conditions without bringing the user any harm. This project has no structure, per se, and no sharp edges to be concerned about.

14 Student TeamThe team is comprised of 4 MIT undergraduates (a more detailed biography on them is provided in the appendices): Samidh Chakrabarti (computer science and brain and cognitive sciences major, class of 2001), Ra Krikorian (computer science major, architecture minor, class of 2000), Sharmila Singh (aeronautics and astronautics major, class of 2001), and Boris Zbarksy (physics and mathematics major, class of 2001).

15 Outreach ProgramThrough our outreach program, it is our hope to encourage elementary school students to take up an interest in the human factors involved in space endeavors. We hope to share our ndings with the students through visits to schools, interactive web pages, and printed material. The following topics will be addressed: the ear and its structures hearing 15

how the brain processes sound binaural recording sound localization reduced gravity summary of our experiment results of the experiment Visits to schools will be of primary importance. We will speak with the students about our experiment and ight experience. The classroom setting will allow us to answer questions directly and also o er us the opportunity to do sound localization demonstrations. We feel that this is the best way to give students a better feel for what it means to locate a sound in three dimensions. We have been in contact with Sue Zobel-Whitcher, a science teacher at the Lincoln School, in Brookline, MA and she is very interested to have our team come out and brief the students before and after the ight. In our brief discussions with Ms. Zobel-Whitcher, it sounds as if she is running a very progressive science program and our experiments should t in perfectly. The Cambridge Public Library and the Boston Museum of Science separately run summer programs for local elementary kids, and we also plan to speak with them and educate this group of children. The Museum of Science (MOS) in particular represents a unique opportunity. We can design and construct an exhibit for the MOS based on our micro-gravity sound localization experiment. Since the MOS hosts a large volume of visitors annually, our project will be exposed to a wide audience of all ages. Our web page will allow students to learn about sound localization over the Internet. The page will include sample sound clips, pictures of our ight, and a multitude of information on the subjects listed above. We plan to create an interactive learning environment through this e ort, so that we can reach out to students whose classroom we do not have the opportunity to visit. In addition to the information online, students will be able to e-mail their questions directly to any member of the team and get a personal response to their inquiry. We will be attaching this web page o the 16.00 course web page (http://web.mit.edu/16.00) at MIT { Introduction to Aerospace and Design. We will have printed material available for distribution in schools. This material will cover the main topics listed above and have pictures from the ight. This material will supplement our visits and provide those without web access the same resources found on the web page. Finally, to address the more scienti c community, we plan to compose a paper with our ndings for publication in a journal. We will also be covered in the MIT Tech, and will prepare a short presentation for the AIAA Northeast Regional Conference which will be held during April. The study of sound localization is of great interest to us, and we hope to convey our enthusiasm to the students. Through our visits, web page, and 16

written material, we feel we will provide young people with useful information and a desire to learn more about space related experiments and about sound localization.

16 JournalistSteve Chazin, of Apple Computer, will be covering this team. He will be joining us on the ground to document the team along with the Apple press liasons from Houston. Mr. Chazin himself will be ying with this team.

17 SchedulingThis is our proposed schedule starting in January of 1999 for preparations if we are chosen to y in March. February 1 Obtain the binaural software from Wave Arts, Inc. Begin creating binaural records February 7 Author the testing software Feburary 15 Receive the KU 100 Dummy Head from Neuman to record the binaural sounds Feburary 25 Debug software and re ne experimental procedures

18 Project SupportWe have contacted Helen Halaris of the Massachusetts Space Grant to see if they can provide any supplemental help. Also, we have asked corporations to sponsor our team by providing us with equipment to be used in preparation of the ight and during the ight. The current sponsors of this team are AKG Acoustics, Neumann Sound, Houston Internet Connect, Wave Arts Inc, Apple Computer, and Lenscrafters.

19 Budget2 Laptops 2 Stereo Headphones 20 DAT tapes 1 DAT Recorder 1 Newman Head 4 Flight Physicals Round Trip Airfare Hotel stay Total $2000/each $35/each $5/each $600 $400/each $150/each $750/each $30/night/each $10450 on loan from experimenters on loan from experimenter hopefully can get on loan -$5000 (on loan or donated)

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20 SummaryThis experiment will attempt to deduce what changes happen to the human body's ability to localize sound when in a micro-gravity environment. By using our custom software, and binaural sound recordings, we will attempt to test the limits of the human body's sound localization abilities. We expect there to be no change in the horizontal plane as that does not require an up or down queue { but we do expect the vertical tests to show that the ability to localize sound diminishes since there is no aid for an absolute up or down. This research can be used to gain better insight into space sickness as well as aid in the design of space craft, space communication systems, and earth-bound space simulators.

21 References1. Blauert, Jens. Spatial Hearing: The Psychophysics of Human Sound Localization. Cambridge, Massachusetts: MIT Press, 1997. 2. Carlile, Simon. Virtual Auditory Space: Generation and Applications. Austin, Texas: Chapman & Hall, 1996. 3. Persterer A, Opitz M, Koppensteiner C. \AUDIMIR: Directional Hearing at Microgravity." Journal of the Audio Engineering Society, Vol. 41(4), pp. 239-247. 4. Yost W, Gourevitch G. Directional Hearing. New York: Springer-Verlag, 1987.

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A Appendix I - BiosSamidh Chakrabarti was born in Corvallis, Oregon in September of 1979. At the age of six, he saw the rings of Saturn through a telescope for the rst time. That single image ignited his passion for space exploration and science. Samidh even submitted an experiment proposal to NASA when he was eight years old in the hopes of studying "A Child's Perspective of Zero-G." Although that proposal proved futile (can you guess why?), Samidh hopes that this proposal will give him the opportunity to conduct serious scienti c research while simultaneously paying homage to his rejected proposal of a decade ago. Samidh chose to attend MIT for college, where he is currently a sophomore majoring in both Computer Science (course 6) and Brain and Cognitive Science (course 9). He is especially excited about this experiment because it combines his passion for computers, brain research, and space research. As the community outreach chair for the MIT chapter of the Students for the Exploration and Development of Space (SEDS), Samidh is looking forward to sharing his experiences in this project with as many kids as possible. In those brief periods of time not spent doing homework or sleeping, Samidh enjoys photography, astronomy, and playing soccer. Ra Krikorian was born in Queens, New York in July of 1978. His life was lled with building stu out of LEGOs. Soon after that he moved to Freehold, NJ and nally to New City, NY. High school was pretty boring. so it was spent competing in lots of competitions to keep him from having to attend class. He then decided to attend MIT, and his life just became way too busy. Now he doesn't have time for anything fun. He is majoring in Computer Science, with a focus in Arti cial Intelligence and realistic simulated environments, and also minoring in Architecture (because he was tired not getting to build stu with his hands). But when he does nd free time, he loves to read, draw, rollerblade, and play classical piano.

A.1 Samidh Chakrabarti

A.2 Ra Krikorian

A.3 Sharmila Singh

Sharmila Singh was born in Jamaica in 1978. In the spring of 1979, she moved to Midland, Texas where her family currently resides. During her school years, she developed a love for science and the humanities and became involved in many of her school's academic teams. She also enjoyed playing basketball and debating. While in high school, Sharmi became interested in aerospace medicine. It was her desire to enter this eld that lead her to MIT for undergraduate study. Sharmi is currently a sophomore at MIT doing pre-medical studies and majoring in Aeronautical Engineering. When not in the classroom or slaving over problem sets, she enjoys reading science ction, playing board games, taking 19

part in religious activities, and sleeping. On longer breaks, she enjoys international travel and spending time with her family. Boris Zbarsky was born in Odessa, Ukraine in November 1979 (missing the 80's by less than 2 months), and moved to Rockville, MD in 1988 (which means he did not miss Chernobyl. Though that may not be as harmful as the 80's). After making his way through what remained of elementary and middle school, he got to high school, which was just the same except for the fact that he joined the math team and took a physics class he really liked. Which brings us to today. He is currently a sophomore majoring in physics and theoretical mathematics. When not doing homework, he can usually be found watching movies, swing dancing (especially lindy hop), rollerblading, coding in Perl, reading sci/fantasy, or, in recurring ts of delusion, discussing abstract algebra or physics with others who are similarly deluded. Prolonged exposure may result in interest in math.

A.4 Boris Zbarsky

B Appendix II - Student AdvisorsB.1 Col. Peter YoungCol Peter Young, an MIT RGSFO advisor, is a Visiting Lecturer in the Department of Aeronautics and Astronautics on loan from the USAF. In his 29 year career in the Air Force, he has spent the majority of his assignments in the space and missile sectors. He has served in several military satellite program o ces for the AF's O ce of Special Projects and was the USAF lead integrator for two STS DoD missions own in the late 1980s. In his most recent assignments he was the Program Manager for the DoD Space Test Program (1995-1996) and the Space Based InfraRed - Low Program. He holds a Bachelor of Science in Aeronautical and Astronautical Engineering from MIT and a Master of Science in Systems Management from the University of Southern California.

Dr. Newman specializes in investigating human movement and motor control performance across the spectrum of gravity. She was Principal Investigator for the Dynamic Load Sensors (DLS) experiment that measured astronaut-induced disturbances of the microgravity environment - a space ight experiment that ew on Shuttle Mission STS-62. A current manifestation, the Enhanced Dynamic Load Sensors, ew on board the Russian Mir space station from 1996 through 1998. Data are helping NASA verify and update design requirements for the International Space Station. Dr. Newman was a Co-Investigator on the Mental Workload and Performance Experiment (MWPE) that ew to space on STS-42 to measure mental workload and ne motor control in microgravity. She 20

B.2 Professor Dava Newman

also has active research e orts in human biomechanics and energetics, robotics, and designing future space suits to be used on Mars.

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