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NASA Technical Memorandum 102177

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-- JSC Director's Discretiona_ Fund

Program

1990 Annual Report

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_NASA-TM-I.02177) -JSC OIK_CTOR'S

DISCRETIONARY FUND pROGRAM _nnual

1990 (NASA) 99 p

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Report,

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Compiled by

New Initiatives Office

Lyndon B. Johnson Space Center

N/ A

Nalm)nai Aeronauhcs and

Space Adm_n_slrat,on
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NASA Technical Memorandum 102177

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JSC Director's Discretionary

Program

1990 Annual Report

Fund

Compiled by

New Initiatives Office

Lyndon B, Johnson Space Center

Houston, Texas

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Preface

The concept of providing a center director's discretionary fund (CDDF) to support

research projects has been very effective at the Lyndon B. Johnson Space Center. The

projects described in this report include the results of research that has its roots linked

to engineering applications. The reader is provided with invaluable information from a

broad experience base. The selection of individual projects also provides an incentive to

young engineers for future project development. Funding for FY90 was $1340k which

was distributed among twenty-five projects with participation across the Center directorates. By focusing on three Space Exploration Initiative related issues: regenerative

life support, human spacecraft design, and lunar surface habitat, a viable program of

life sciences, space sciences, and engineering research has been maintained.

The guidelines for selection of proposed projects for funding include an emphasis on inhouse work, a project span of 3 years or less at a nominal funding level of $50k per year

that is not available from other sources, an early identifiable product, and the potential

for a new start with specific funding support. The following is a brief status on some of

the projects with broad potential application.

Artificial intelligence techniques were incorporated into a prototype system to

assess the production schedules for Space Shuttle flight software. It has resulted in

reducing evaluation personnel by three people.

• Testing of diluent gases in oxygen rich environments showed potential benefits by

inhibiting combustion.

• Holographic analysis techniques were successfully applied to the understanding of

rocket engine stability and for the detection of defects in metallic systems.

Testing of antenna performance began on various antenna configurations in order

to investigate the advantages of high-temperature superconductors.

Concepts for analysis of planetary soils are being developed. Thermoanalytic

methods are emphasizing a bench test version of a differential scanning calorimeter

module mated with a solid state water sensor. A research grade Mossbauer spectrometer is used in backscatter spectroscopy testing.

Reducing the effects of space flight by developing an optimum protocol for lower

body negative pressure and fluid loading solution is continuing.

The regenerative life support system test bed project outfitted the variable pressure

growth chamber with plant growth systems as part of a long-term commitment to

the research needed in this vital exploration technology.

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The lunar surface systems habitat test bed is being used to stimulate creative and

innovative approaches to human habitation in extreme environments.

• The Targeting and Reflective Alignment Concept, the most significant_invention, of

the year, is being interfaced with rhacl_in6 vision programs to automate grappling

with manipulators in space.

• Burn resistant alloys were tested at the White Sands missile range indicating an

increased resistance by adding lithium to aluminum alloys.

• Gamma-ray counting facilities devel6ped for the trace eiement analysis of cosmic

dust were used extensively for analysis of radiation effects on the Long Duration

Exposure Facility.

The team at the White Sands Test Facility has been particularly efficient in their use of

the CDDF. The facilities and individuals that initiated and conducted the follow-up

research on the projects included in this report provide a unique capability to the

agency.

For additional information on the projects listed in this report, contact the individual

investigators or Lyle Jenkins at (713) 283-5405,

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Manhger, New Initiatives Office

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CONTENTS

Project Page

Laser-Based Plasma Flow Diagnostics

Eric Yuen ....................................................................................................................... 1

Distributed Artificial Intelligence Based Schedule Assessment

or Space Shuttle Flight Software Production

John F. Muratore ........................................................................................ i................... l0

Diluent Gas Studies in HighPressure Oxygen Systems

Radel Bunker .................................................................................................................. 12

Holographic Vibration Analysis of a Small Flight-Weight Rocket Engine

John Mulholland ............................................................................................................. 18

Development of an Optical Analysis System/Technique

for Shuttle Component Analysis

John Mulholland .............................................................................................. .............. 21

Orbital Debris Radar Ground Studies

G.D. Arndt ..................................................................................................................... 25

High-Temperature Superconductor Antenna Investigation

Phong H. Ngo ................................................................................................................. 27

Thermal Analyzer for Planetary Soils (TAPS)

James L. Gooding ............................................................................................................ 30

Lymphocyte Activation in Simulated Microgravity and Hypergravity

Clarence F. Sams ............................................................................................................ 38

Plasma Volume and Orthostatic Tolerance

Suzanne M. Fortney, Ph.D ............................................................................................ 41

Neural Network Modeling of Postural Control

Millard F. Reschke, Ph.D ............................................................................................... 45

Backscatter Mossbauer Spectroscopy (BaMS) for Analysis of

Planetary Surface Materials

Richard V. Morris ........................................................................................... ,.............. 55

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Project Page

Regenerative Life Support Systems (RLSSs) Test Bed Project

:_A!bert F. Behrend ............................................................................................................. 59

Mockup of a Constructible Lunar Habitat

Michael Roberts ................................................................................................................ 62

Adaptive Control of a Robot Arm Using an Artificial Neural Net

with Stereo Vision Input

Timothy G. Cleghorn, Ph.D ............................................................................................. 64

Psychosocial Support for Long-Duration Missions

Patricia A. Santy, M.D ........................................................................................ ............ 66

Evaluation of New Body Composition Techniques in Variable Gs ....

Steven F. Siconolfi, Ph.D ................................................................................................. 67

Automated Grappling Control for the Space Shuttle Remote

Manipulator System Utilizing the Magnetic End Effector and the

Targeting and Reflective Alignment Concept (TRAC)

Timothy F. Cleghorn, Ph.D ............................................................................................ 69

Doubly Labeled Water Technique

Helen W. Lane and Everet K. Gibson 70

Development of Alloys with Improved Burn Resistance

Joel Stoltzfus ..................................................................................................................... 72

Trace Element Analysis of Individual Cosmic Dust Microparticles

Michael E. Zolensky, David ]. Lindstrom, and Marilyn M. Lindstrom ......................... 76

Human Spacecraft Design

Clarence A. Bell and Ann Bufkin 78

High Resolution Optical Rate Sensor

Joseph Thibodeau and Indulis Saulietis ........................................................................... 80

Network-Based Video Image Link

Charles R. Price ................................................................................................................ 82

Lunar Base Mockups

Nathan Moore ................................................................................................................... 84

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Table

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TABLES

Page

A SUMMARY OF THE TEST CONDITIONS ............................................................ 2

RESULTS OF FLAMMABILITY TESTS ON NICKEL-BINARY ALLOYS ............. 75

FIGURES

Page

Experimental setup of Doppler velocimetry in ARMSEF ...................................... 5

Electronics block diagram of the experiment ........................................................... 6

A typical laser-induced fluorescence spectrum of copper atom

superimposed by the computed spectrum ............................................................. 7

Comparison between measured and computed temperature

at different enthalpy (arc jet temperature) .............................................................. 8

Comparison between measured and computed velocity at different

enthalpy (arc jet velocity) ............................................................................................ 9

Promoted combustion chamber ................................................................................. 14

Diluent tests, PTFE teflon ............................................................................................ 15

Diluent tests, Vitron ..................................................................................................... 16

Diluent tests, Kel-F 81 .................................................................................................. 17

Test system in firing configuration (front view) ...................................................... 19

Test system in firing configuration (side view) ....................................................... 20

TV hologram of PRCS engine during post-test heat soak ...................................... 20

23 Optical analysis system prototype .............................................................................

Optical analysis system showing disbond condition on airframe structure ....... 24

Antenna subsection ...................................................................................................... 26

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Figure Page

16 Complete antenna test set-up ...................................................................................... 29

17 TAPS functional diagram (experiment functions) .................................................... 34

18 Experimentally determined DSC sensitivities .......................................................... 35

19 Experimentally determined response of a candidate solid-state TAPS water

sensor to cooling below dewpoint (left) and sudden exposure to a pulse of

humid air (right), as simulations of evolved-gas analysis ...................................... 36

20 Experimentally determined sample-acquisition performance of the TAPS

Mark-1 sample probe which is based on a spinning-paddle design ..................... 31

21 Activation of lymphocytes. Lymphocytes were activated with 2_tg/ml phytohemagglutinin for 24 hours in sealed tubes which were static (PHA) or placed

on a blood rocker to gently suspend cells (s-PHA). Activation was measure

by the percentage of CD69 positive cells as determined by immunofluorescent

labeling and flow cytometry. Data area presented as percent CD69 positive

cells vs. time after mitogen addition .......................................................................... 40

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23

LBNP treatment pressure profile ................................................................................ 42

2_;;;__ _ "_ _7 -" v'-'_: _- -_÷-_- ..... _ ...... _ .....

Sensory organization test conditions. The symbols on the right indicate the

visual, vestibular, and ankle proprioceptive sensory inputs used during that

test condition. Sway referenced conditions are those in which the visual surround and/or support surface are directly servo controlled to body sway

thereby providing orientationally inaccurate information. (Figure copyright

by Neurocom, Inc.; used with permission.) .............................................................. 50

24 STNN architectural features; in both cases note the mapping of input time

series to output time series.

a) STNN processing element comparable to standard BP network except for

the weight vector which replaces the BP weight scalar ..................................... 51

b) Representation of STNN emphasizing the weight vectors interconnections

between layers of processing elements ................................................................ 51

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Figure

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Topology of 11-channel STNN network (auto- and heteroassociator).

Note that (for clarity) each weight vector is represented by a single line

and that the number of hidden units is variable as described in the text ........... 52

26 A 3-D plot of STNN autoassociator hidden unit activation values for network

trained with Subject #2 SOT #1, SOT #6 (pre-PAT), and SOT #6 (post-PAT)

data only. Note the 200-point trajectories in each case.

a) Composite plot ....................................................................................................... 53

b) SOT #1 ..................................................................................................................... 53

c) SOT #6 (pre-PAT) ................................................................................................... 53

d) SOT #6 (post-PAT) ................................................................................................ 53

27 A 2-D plot of BP autoassociator hidden unit activation values for network

trained with SOT #1 and SOT #6 (pre-PAT) data for five subjects. Note distinct clustering and segregation of data points ....................................................... 54

28 Transmission Mossbauer spectra .............................................................................. 57

29 Backscatter Mossbauer spectrometer (BaMS) ......................................................... 58

30 The RLSS Test Bed Facility layout ........................................................................... 61

31 Optical rate sensor experiment .................................................................................. 8!

32 Interior view of telerobotic workstations ................................................................. 86

33 Exterior view showing airlock, radiation protection, and radiators .................... 87

34 Interior view of topology ........................................................................................... 88

35 Interior view of wardroom galley area .................................................................... 89

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TITLE OF INVESTIGATION:

PROJECT MANAGER: Eric Yuen/ES36/483-5950

TEAM MEMBER: Carl Scott, NASA;

Sivaram Arepalli, Lockheed

INITIATION YEAR: FY88

FUNDING:

In-house:

CDDF:

Total funds:

Laser-Based Plasma Flow Diagnostics

Total prior years FY90

31k

53k 25k

84k 25k

OBJECTIVE

The Laser-Based Plasma Flow Diagnostics project has been developed in order to gain

a better understanding of the hypersonic flow field. This nonintrusive laser-based

technique can measure flow parameters such as velocity, temperature, and number

densities of the flow constituents. This information is the necessary input for computational fluid dynamics calculations as well as heat transfer analyses. The objective of this

project is to demonstrate the feasibility of the laser-based technique in the Atmospheric

Reentry Materials and Structures Evaluation Facility (ARMSEF) at the Lyndon B. Johnson Space Center. The feasibility study includes (1) identification of the necessary lasers

and detection electronics; (2) procurement of equipment; (3) integration of lasers and

electronics into the existing arc-jet facility; and (4) the recording of flow field measurements (temperature, velocity, and number densities) under real test conditions.

ACCOMPLISHMENTS IN FY90

The free-stream velocity and temperature measured in the ARMSEF simulates the

atmospheric entry of spacecrafts. The technique of resonance Doppler velocimetry is

employed using the laser-induced fluorescence (LIF) of copper atoms in the free-stream

flow. Copper atoms sputtered from the anode continuously when there was current

between the electrodes of the DC constricted arc heater. These copper atoms were used

as tracer atoms to provide information of the free-stream velocity and temperature. The

test conditions for these measurements is given in table 1.
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TABLE 1.- A SUMMARY OF THE TEST CONDITIONS w

Massflowrate Current Pressure Enthalpy Velocity Temperature

k/s A N/m2 mJ/kg m/s K W

0.0454 700 4265 13.1 2853 2022

0.0454 500 3546 9.9 2673 1457 w

0.0454 300 2827 6.5 1952 1017

0.0681 700 5654 11.4 2853 1148

0.0908 700 6900 9.4 2132 1486

0.0908 500 5654 7.2 1952 1478

0.0908 300 4648 4.5 1320 498

0.1135 700 7427 8.7 2492 1076

The setup of the experiment is shown in figure 1. A Nd:YAG (neodynium doped yttrium aluminum garnet) laser, which produced a 350-mJ pulse of 532-nm second harmonic radiation, was used to pump a dye laser resulting in an 80-mJ/pulse of 655 nm

radiation. The 655-nm laser pulses were frequency doubled using a KD*P (potassium

di-deuterium phosphate) crystal to produce an 8-mJ/pulse of 327.5 nm radiation. By

using an intracavity etalon in the dye laser, the linewidth of the 327.5-nm laser pulse_ ilimited to 0.08 cm-_(2400 MHz). The laser beam was then steered into the test chamber

at either a right angle or 60 ° from the flow direction. The LIF signal was collected by a

photomultiplier tube (PMT)at 9_0°__toboth the lase_r be_am andthe flow dire cti'_on. The_

PMT operated in the photon counting mode. The output of the PMT was fed directly

into two gated channels of a photon counter. The photon counter was then used in a

background subtract mode. The photon count and the laser frequency information

were sent to an X-Y recorder to construct an LIF spectrum. The basic electronic block

diagram is shown in figure 2.

All measurements were made at the centerline of the plasma flow: 12.5 cm from the

nozzle exit. The measured Doppler profiles, like the one shown in figure 3, were used

to determine the velocity and temperature. The velocity of the plasma flow was obtained by comparing the wavelength shift of the LIF spectrum measured at 60 ° and the

LIF spectrum obtained at 90 ° using the expression:

V'-" c 0A v (1)

o COS V

where v is the velocity of the plasma flow, c is the speed of light in vacuum, v o is

unshifted frequency of the transition, 0 is the angle between the laser beam and the

plasma flow, and Av is the shift frequency. To determine the temperature of the

plasma, a nonlinear least squares curve fit code was used. A quadruplet Gaussian

profile was assumed for the four hyperfine levels. The functional form of the

quadruplet is

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'(v'T): aiexp,=i 4 E-mcu 2kT o(v-v°-vt)t

(2)

where aj is the line weight, mcu is the mass of the copper atom, v 0 is the line reference

wavenumber, vj is the offset from the reference for each component, T is the absolute

temperature, and c is the speed of light. The least squares determination of the temperature was found by minimizing, with respect to the temperature, the relation

N

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i=1

(3)

where N is the number of measured points defining the Doppler profile, Ii are the

measured intensities suitably normalized, and I(ni,T) is the calculated intensity formed

by folding Eq.(2) with the laser profile and suitably normalizing the result. The relative

intensities of the four hyperfine levels (the _) was assumed to be 1.0:1.0:0.6:0.3. These

were obtained from measurements of a c01d copper atom using a single frequency dye

laser (ref. 1). The results of the curve fits are shown in figure 4, where the Doppler

temperature is plotted against total heat balance enthalpy. The results are compared

with calculations made using the 1-dimensional, nonequilibrium flow code NATA (ref.

2) and those obtained by solving the conservation equations (refs. 3, 4, and 5).

1V2 h T=_ =+OCNh N+CpT= (4)

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mg = p .V=Aef f

(6)

where h r is the total enthalpy, hN is the enthalpy of dissociation of nitrogen, V is the

freestream velocity, T is the freestream temperature, p. is the freestream density, P is

the freestream pressure, PT2 is the stagnation pressure, a N is the nitrogen atom mass

fraction, Cp is the heat capacity of nitrogen at constant pressure, mg is the massflow

rate, and Aeff is the area of inviscid core of nozzle flow at the nozzle exit.

The comparison between the NATA code, the solution to the conservation equations,

and the measurements are shown in figures 4 and 5. The results do not agree very well,

indicating that the assumptions used in the calculations may not be adequate.

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PLANNED FUTURE WORK

All of the objectives outlined in this investigation have been met. When the test facilities come back online after the C of F project, the velocity and temperature of the arc jet

flow will be measured at various test conditions and at different positions to provide a

3-dimensional picture of the flow field.

PUBLICATION AND PRESENTATION

,, AIAA/ASME 5th Joint Thermophysics and'Heat Transfer Conference, June 18-20,

1990 / Seattle, WA.

Sivaram Arepalli, Eric H. Yuen and Carl D. Scott, "Application of Laser Induced

Fluorescence for Flow Diagnostics in Arc Jet", to be published in Journal of

Thermophysics and Heat Transfer.

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REFERENCES _ .......... _ ....

1. Chen, Hao-Lin; and Erbert, G.: Laser Studies of Electronic Energy Transfer in Atomic

Copper. Journal of Chemical Physics, vol. 78, April 1983, pp. 4985-4990.

2. Bade, W. L.; and Yos, J. M.: The NATA Code - Theory and Analysis. NASA

CR2547, 1975. _

° Scott, C. D.: Catalytic Recombination of Nitrogen and Oxygen on High Temperature

Reusable Surface Insulation. Progress in Astronautics and Aeronautics:

Aerothemodynamics and Planetary Entry, vol. 77, edited by A. L. Crosbie, AIAA,

New York, 1981, pp. 192-212.

4. Scott, C. D.: Catalytic Recombination of Nitrogen and Oxygen on Iron-CobaltChromia Spinel. AIAA Paper 83-0585, January 1983.

5. Scott, C. D.: Survey of Measurements of Flow Properties in Arc Jets. AIAA Paper

90-1795, 1990.

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Figure 1. Experimental setup of Doppler velocimetry in ARMSEF.

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Figure 2. Electronics block diagram of the experiment.

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Figure 3. A typical laser induced fluorescence spectrum of copper

atom superimposed by the computer spectrum.

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Figure 4, Comparison between measured and computed

temperature at different enthalpy (arc jet temperature).

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Enthalpy (mJ/kg)

Figure 5. Comparison between measured and computed

velocity at different enthalpy (arc jet velocity).

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PROJECT TITLE: Distributed Artificial Intelligence Based Schedule

Assessment for Space Shuttle Flight Software Production

PROJECT MANAGER: John F. Muratore, DP 483-0796

INITIATION YEAR: FY90

FUNDING: FY90 FY91 FY92 Total

Funding: 40k 40k 0 80k

Cost: 13 55(est.) 12(est.) 80

Carryover: 27 12 0 0

OBJECTIVES

The objective of the Distributed Artificial Intelligence Based Schedule Assessment for

Space Shuttle Flight Software Production is to develop a tool to assist the Mission Operations Directorate, Reconfiguration Management Division (DP) in coordinating the

many schedule details in the production of flight software. The development of multiple options for evaluation is required. The goal of this project is the effective application of new technology to the flight software reconfiguration process scheduling. This

local workstation system shall have the capability to perform "what-if" options for

evaluation using a combination of conventional and artificial-intelligence-based tools.

The final results will be communicated electronically back to the mainframe-based

scheduler. These capabilities shall enhance the flight software production process by

providing multiple options for evaluation. Quality improvements are expected in the

generation of better scheduling, planning, and resource utilization in the flight software

production including the integration of multimission planning. Using the local workstation will allow faster response to changes and earlier identification of schedule problems; thus, allowing more time to work resource problems which will become more

critical as the flight rate increases.

ACCOMPLISHMENTS IN FY90

A proof of concept prototype system was successfully developed sharing office PCs

utilizing Civil Service manpower. Two workstations and a plotter were purchased in

order to implement a full up local system and support continued system development.

This system is currently being used in a limited way to conduct schedule evaluations.

The use of this system has resulted in a manpower savings of three people being required for flight software production schedule assessments.

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PLANNED FUTURE WORK

This organization is committed to the continued development of the Distributed Artificial Intelligence Based Schedule Assessment for Space Shuttle Flight Software Production through the maturity of the project. Flight software reconfiguration production

electronic interface hardware and software will be purchased to implement a fully

integrated scheduling system. Testing and certification of this system will be completed

and final upgrades will be identified and implemented as the availability of resources

allows. This system will finally be integrated with the Space Station Freedom Program

flight software development efforts.

EXPECTED COMPLETION DATE

The current scope of the project will be completed by October 1992.

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TITLE OF INVESTIGATION: Diluent Gas Studies in High Pressure Oxygen Systems

PROJECT MANAGER: Radel Bunker/RA/FTS 572-5733

TEAM MEMBER: David Hirsch - Lockheed-ESC White Sands Test Facility

INITIATION YEAR: FY89

FUNDING: Total prior years FY90

In-house: 35k 65k

OBJECTIVE

Considerable effort is expended by NASA to assure that materials used in habitable,

oxygen-enriched environments do not present a fire hazard. Even though these efforts

have been highly successful, catastrophic system failures have occurred due to fires

initiated by polymeric materials. Some limited studies have indicated that small quantities of certain diluent gases can reduce material flammability. If this is the case, safer

life support systems and hyperbaric chambers designed for Shuttle and Space Station

Freedom which use or will use polymeric materials in high pressure oxygen systems

can be designed.

The objective of this project is to determine if there is a physiologically acceptable

diluent gas that can be added to oxygen-enriched environments that will significantly

reduce the ignition and subsequent combustion of materials.

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ACCOMPLISHMENTS IN FY90

Approximately 200 combustion experiments were performed using the White Sands

Test Facility Promoted Combustion System shown in figure 6. These experiments were

conducted with nitrogen (N2), helium (He), and argon (Ar) at pressures of 1000 psia and

3000 psia. PTFE Teflon, Kel-F81, and Vitron which are typically used in high pressure

0 2 system were selected as the test materials. Some preliminary studies were also

conducted with PTFE Teflon at 5000 psia using N 2 and He. The results from these

experiments are shown in figures 7, 8, and 9 and indicate the following conclusions:

Helium, which provides a weight benefit over the other diluent gases tested, was

the most effective diluent in inhibiting flame propagation followed by N 2 and then

Ar.

• Large quantities of diluent gases, approximately 60 percent or greater, were required

to prevent flame propagation of the materials tested; however, the resulting diluent/

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oxygen mixtures were still breathable. However, the use of He can present a voice

intelligibility problem.

The effect of pressure on the diluent concentration required to inhibit flame propagation was small at pressures greater than 1000 psia. This result indicates that

breathable oxygen mixtures can be stored and used at high pressures (greater than

5000 psi) without increasing fire hazards for the materials tested.

Based on the results for this project, the Kennedy Space Center is planning to use the

test methods developed in this project to evaluate material for use in high pressure life

support systems.

The last major accomplishment in FY90 was the acceptance for publication of the paper

entitled "Effects of Oxygen Concentration, Diluents, and Pressure on Ignition and

Flame Spread Rates of Nonmetals: A Review Paper" (ref. 1).

PLANNED FUTURE WORK

Approximately $10k has been requested for FY91 to perform combustion studies with

Ne at 1000 psia. The quantity of neon (Ne) required to prevent flame propagation is

anticipated to fall between He and N2; thus making it a better diluent than N 2 but

without the voice intelligibility effects of He. These results and the results previously

described will then be submitted in a paper to several fire science journals.

EXPECTED COMPLETION DATE

FY91

,..,,.

REFERENCE

. Hirsch, D.B.; Bunker, R.L.; and Janoff, D.: Effects of Oxygen Concentration,

Diluents, and Pressure on Ignition and Flame Spread Rates of Nonmetals. Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres: vol. 5,

ASTMSTP 1111, edited by Joel M. Stoltzfus and Kenneth McIlroy, American

Society for Testing and Materials, Philadelphia, 1991.

13
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Pressure (psia) (thousands)

N2-oxygen index -..1..--N2 --_-- Ar _ He

Figure 7. Diluent tests, PTFE teflon.

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X100461M

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100

80

60

40

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-'"'- N2-oxygen index

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Pressure (psia) (thousands)

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Xt 00462M

Figure 8. Diluent tests, Vitron.

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Pressure (psia) (thousands)

--'-- N2-oxygen index -'_-- N2 -'_--- Ar ...El-. He

Figure 9. Diluent tests, Kel-F 81.

X100463M

17
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TITLE OF INVESTIGATION: Holographic Vibration Analysis of a Small FlightWeight Rocket Engine

PROJECT MANAGER: John Mulholland/RA/Frs 572-5516

TEAM MEMBERS: John Tyrer - Loughborough University of Technology

Robert Cort - Lockheed-ESC White Sands Test

Facility

INITIATION YEAR: FY88

FUNDING:

In-house:

Total prior years FY90

120k 60k

OBJECTIVE

The objective of this project was to develop an interferometric technique capable of

providing nonintrusive, precise stability measurement of a primary reaction control

system (PRCS) engine. The relatively new holographic technique that was investigated,

electronic speckle pattern interferometry (ESPI) (or TV holography), provides real-time

global mapping of small surface displacements using electronic processing and video

recording and display. The ESPI system, which is based on!aser illumination, allows

displacement measurements with sensitivities proportional'to the wavelength of light.

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ACCOMPLISHMENTS IN FY90

The major goals in FY90 were to conduct hot-fire tests to provide proof-of-concept that

ESPI is a viable engine stability analysis method. The test stand fabrication in support

of testing was completed in early July followed by a series of PRCS hot-fire tests. Figures 10 and 11 show the test system in firing configuration. The hot-fire testing provided excellent results, and has proven the applicability of ESPI technology for rocket

engine vibration analysis. Figure 12 is an actual TV hologram of the PRCS engine

during post-test heat soak back. Complete data reduction is still in progress in coordination with Loughborough University of Technology, Leicestershire, England, which

has provided support throughout the project. A paper will be presented at the next

Society of Photo-Optical Instrumentation Engineering conference.

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PLANNED FUTURE WORK

The results of this project were presented to NASA Headquarters, along with a proposal

to develop a deliverable package for engine stability analysis. This new project would

be a 3-year effort at $300k a year and bridge the gap between the proof-of-concept

system and the necessary high-power rugged system required for field testing.

EXPECTED COMPLETION DATE

This project was completed in FY90.

Figure 10. Test system in firing configuration (front view).

ORIGINAl' PAGE

BLACK AND WHITE PHOTOGRAPH

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Figure 11. Test system in firing configuration (side view).

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Figure 12. TV hologram of PRCS engine during post-test heat soak.

2o

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

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TITLE OF INVESTIGATION: Development of an Optical Analysis System/Technique

for Shuttle Component Analysis

PROJECT MANAGER: John Mulholland/RA/FTS 572-5516

TEAM MEMBERS: Larryl Matthews - New Mexico State University

Joseph Genin - New Mexico State University

Mike McNeely - NASA White Sands Test Facility

Lawrence Brooks - Lockheed-ESC White Sands Test Facility

INITIATION YEAR: FY89

FUNDING: Total prior years FY90

In-house: 40k 50k

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OBJECTIVE

The objective of this project was to develop self-contained, portable test equipment and

procedures for rapid response testing and evaluation of space-related critical components. The specific need for this type of a system became apparent during the STS-26

dynatube leak anomaly investigation. There were no in-place techniques to nonintrusively determine stresses, strains, torque, cracks, etc., on this component while installed in the vehicle. There are many Space Shuttle and Space Station Freedom systems

where limited physical access also prohibits the use of traditional test methods such as

ultrasonics and x ray. This project is designed to provide holographic test apparatus

capable of accessing components in restrictive areas.

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ACCOMPLISHMENTS IN FY90

The development of the prototype test system was completed (fig. 13) and tests to

demonstrate the feasibility of the concept for aerospace applications were performed.

In one series of tests, an airframe structure was evaluated in a joint effort with New

Mexico State University. A disbond in the structure was detected (see TV monitor in

fig. 14) which demonstrated the applicability of the holographic methods for health

monitoring of such structures.

In another series of tests, welded thin wall tubing was evaluated for flaws. The results

proved that holographic methods are capable of detecting flaws in welds and, in some

cases, this method was more sensitive than traditional x-ray analysis. The results were

presented in a paper entitled "Holographic Analysis as an Inspection Method for

Welded Thin Wall Tubing" (ref.1). In addition, preliminary testing was completed to

evaluate the capability of this method to detect flaws in composite materials. Test data

21
m

is presently being analyzed. The overall results to date have indicated that holographic

analysis can provide a valuable tool to detect defects in metallic systems. Future test

results may prove this method will also detect flaws in composite materials.

PLANNED FUTURE WORK

Planned work for FY91 includes the final system fabricatiOn and software development.

Tests will continue to evaluate the capability of holographic methods for detecting flaws

m composite materials and metallic pressure vessels.

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EXPECTED COMPLETION DATE

This project will be completed in FY91.

REFERENCES

o Brooks, L.; Mulholland, J.; Genin, J.; and Matthews L.: Holographic Analysis as an

Inspection Method for Welded Thin Wall Tubing. Proceedings of the 1990 SEM

Spring Conference on Experimental Mechanics, Albuquerque, NM, June 4-6, 1990.

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ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

Figure 13. Optical analysis system prototype.

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ORIGINAL PAGE

BLACK AND WHITE PHOT_H

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TITLE OF INVESTIGATION: Orbital Debris Radar Ground Studies

PROJECT MANAGER:

TEAM MEMBERS: J.H. Suddath and P. Fink

INITIATION YEAR: 1989

FUNDING:

G. D. Arndt/EE3/483-1438

Total prior years FY90

In-house: 40k 45k

Contractors: 0 0

Grants (University): 50 0

Total funds: 90k 45k

OBJECTIVE

Develop and test a low-cost ground demonstration radar system capable of detecting

and tracking small, 1-cm particles traveling at high angular rates. The ground system is

a precursor to a larger spaceborne radar capable of detecting and tracking orbital debris.

r_

ACCOMPLISHMENTS IN FY90

• Built and tested a 4-element (subarrays) Ku-band antenna as shown in figure 15

• Developed high-speed control software for steering and focusing the phased array

antenna

• Initiated Ka-band antenna studies

• Initiated development of a Ku-band radar receiver for subsequent integration of the

antenna

• Performed system studies into antenna requirements for scanning spatial sectors

with maximum likelihood of incoming debris

• Co-authored paper, "Collision Warning and Avoidance Considerations for the

Shuttle and Space Station," AIAA Orbital Debris Conference, Baltimore, MD, 5/90

25
PLANNED FUTURE WORK

Complete fabrication of radar receiver, integrate with antenna breadboard, and

perform testing in anechoic chamber _ -....

• Extend four subarray design into a .5-m by 2.0-m antenna design needed for White

Sands testing

• Perform a system level integration study with the antenna and an infrared detection

system for initial acquisition

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EXPECTED COMPLETION DATE

FY91 will conclude director discretionary funding; Code M RTOP has been submitted

for long-term effort resulting in a spaceborne microwave radar tracking system.

Antenna

RF switch

RF switch

=,_4-bit phase shifter _-

l_4-bit phase shifter

l_4-bit phase shifter ._-

_4-bit phase shifter )

_ 4-Way N

power ._

combiner/

To

receiver

]

Figure 15. Antenna subsection.

X100464M

26

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TITLE OF INVESTIGATION: High-Temperature Superconductor

Antenna Investigation

PROJECT MANAGER: Phong H. Ngo/EE13/483-7990

INITIATION YEAR:

FUNDING:

FY89

In House:

Contractors:

Grants

Total prior years FY90

50k 50k

Total funds 50k 50k

OBJECTIVE

High-temperature superconductors (HTS) offer the promise of greatly improved tracking and communications system performance. The objectives of this project are to

investigate the suitability of applying HTS materials to tracking and communications

system components, specifically to develop an antenna array and other useful circuits

and methods for characterizing HTS material samples and circuit designs and to integrate these components into a flight experiment (see fig. 16).

ACCOMPLISHMENTS IN FY90

• Laboratory equipment

• Accomplishments for FY90 included a complete checkout of the 4.5 K closed-cycle

helium refrigerator. Several problems were found and all have been corrected.

Modification to the cryogenic cooler was made to allow testing of antennas. This

effort includes the extension of the cold-head to reduce the interference caused by

the walls of the chamber and replacing the top lid with several radomes to allow

radiation measurements.

• One all-metal aperture coupled microstrip patch antenna was fabricated and is being

tested.

27
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SPIE Symposium Presentation

An analytical study comparing radiation efficiency and bandwidth of HTS and normal

metal antennas was presented at the SPIE Symposium. _...............

I

PLANNED FUTURE WORK

• In the FY91 year, fabrication, test and characterization of a 30-GHz, 4 by 4 antenna

array utilizing HTS materials in the feed network will be completed.

• Pending RTOP funds, a flight experiment is planned for late 94.

EXPECTED COMPLETION DATE

The CDDF portion of the HTS research should be completed in October 1991.

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- Cu patch

Aperature

HTS

stripline

feed

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HP 6510B_, _',,,_k---- l

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analyzer

Vacuum

Vacuum gauge

Temperature controller

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X100465M

Figure 16. Complete antenna test set-up.

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29
I

TITLE OF INVESTIGATION: Thermal Analyzer for Planetary Soils (TAPS)

PROJECT MANAGER: James L. Gooding/SN21/FTS 525-5126

TEAM MEMBERS: Judith H. Allton, Lockheed Engineering

Space Corporation, (LESC)

Terry B. Byers, LESC

Keith J. Draper, LESC

Howard V. Lauer Jr., LESC

A. James Kettle (University of Newfoundland, Canada; Summer

Intern sponsored by Lunar and Planetary Institute, Houston,

Texas)

INITIATION YEAR: FY1989

FUNDING:

U

In-house (incl. LESC):

Contractors (not LESC):

Grants:

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FY89 FY90

45k 43k

0 2

0 0

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Total funds: 45k 45k i

OBJECTIVE

Exploration of the solar system requires compact instruments for in-situ analysis of

water and related substances in planetary geologic materials. Motivations for such

analyses include scientific investigation of the nature and histories of planetary surfaces

as well as evaluation of the resource potential of planetary materials. Possible applications are as follows:

*Moon: Reconnaissance for ices at the poles and ore minerals elsewhere

*Mars: Identification of ices, water-bearing minerals, carbonates, and nitrates

*Asteroids or Comets: Identification of ices and water-bearing minerals; "fingerprint"

comparison with meteorites

*Venus: Identification of sulfide, oxide, and carbonate minerals

..... LE 2:

The TAPS project is intended to define the scope, purpose, and design considerations

for miniaturized, automated instruments that would perform, through thermoanalytic

methods, in-situ identification of ices, water-bearing minerals, and related substances in

planetary surface soils. This early definition work is necessary before development of

flight experiments can be usefully sponsored by other mainline NASA programs.

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ACCOMPLISHMENTS IN FY1990

The three important functions embodied in TAPS are acquisition of a solid sample,

thermodynamic analysis of the solid sample, and analysis of gases evolved from the

sample during heating (fig. 17). For the analytical functions, several different sensor

types were identified with recognition that actual sensor selections will be influenced by

the choice of planetary target and the instrument mass, volume, and power available on

a specific mission. Our published results included detailed descriptions of the functions, design considerations, and candidate sensor methodologies (refs. 1 and 2) as well

as actual test data for prototype systems (refs. 3, 4, 5, and 6).

To focus various elements of the design process, we selected a differential scanning

calorimeter (DSC) as the thermodynamic analyzer and a single-function water sensor

as the evolved-gas analyzer. The DSC represents the most versatile and powerful

choice for the thermodynamic analyzer; whereas the water sensor represents a simple

approach to analyzing a single (but arguably the most important), volatile compound.

Choices of sample inlet-and-purge systems are varied and are more dependent on the

scope or limitations of individual missions. To facilitate the design and test process,

however, we selected a single rotary paddle design (denoted as the TAPS Mark-1

sample probe) that was created specifically to support the DSC.

Using laboratory instruments, we demonstrated that DSC is a useful material "fingerprinting" method for possible martian and cometary applications (refs. 4 and 5). In

addition, we showed that, for prospective martian applications, DSC is a sensitive

method that can detect and quantitatively measure hydrated silicate, carbonate, sulfate,

and oxides minerals at concentrations as low as 0.5 weight percent (see fig. 18) (ref. 6).

We computed the sensitivity required for a water analyzer that could be mated with a

DSC and found that, for a 10 mg sample containing I weight percent water as a single

mineral, the minimum acceptable dynamic range for the sensor would be 180 to 2100

ppm (by volume); an even wider range would be highly desirable. Based on that estimate, we evaluated published descriptions of various water-sensor technologies and

found five different sensor types that might be suitable for TAPS. Previous studies of

possible planetary water analyzers (by other workers in the 1970s) emphasized phosphorous pentoxide electrolytic cells; but we found that newer, solid-state sensors hold

significant promise for TAPS applications. Although further evaluation of prospective

water sensors will be pursued, we exercised our design and implementation concepts

by constructing a simple, bench-top system based on a piezoelectric quartz oscillator

chilled by a small Peltier-effect electric cooler. A sensor with heating and cooling capacity would be expected to enhance specificity for water in mixed-gas samples. We note

that, for applications on cold planets such as Mars, cooling by the ambient-environmental heat sink might be achieved without additional power consumption. Test data from

our experimental system (fig. 19) were encouraging and showed that simple sensors of

this general category deserve further study.

31
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Laboratory tests of the Mark-1 sample probe functional model (which was designed

and fabricated in FY89) showed that the current design is effective in acquiring DSC

samples (10 to 100 mg) from sand-sized materials but that it will require modifications

for silt-sized materials (fig. 20). This sampling mechanism may not be suitable for all

conceivable versions of TAPS but demonstrates that an analytical instrument with selfcontained sampling capability should be feasible. This approach stands in contrast to

conventional assumptions that a TAPS-style experiment would require an independent,

spacecraft- or vehicle-furnished sampling mechanism.

PLANNED FUTURE WORK

Work in FY91 will focus on assembling a bench-top TAPS analyzer based on a DSC

module mated with a solid-state water sensor. No attempt will be made, at this early

stage, to design an optimized or flight-qualified instrument. Instead, this work will

explore coordinated operation of the two different sensor systems and evaluate the

degree to which theoretical sensitivities of each analyzer can be achieved.

Accomplishments during this 3-year project constitute the pre-Phase A stage of experiment development. The progress we have demonstrated will be carried forward as a

proposal to NASA Headquarters for a Phase A definition and development of a version

of TAPS that would be suitable for specific flight opportunities. At present, the most _

reasonable pre-project candidate is the Mars Environmental Survey (MESUR) mission

although recently emerging opportunities in the Comet Rendezvous and Asteroid Flyby

mission will also be explored. _

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EXPECTED COMPLETION DATE _ _ _ ..... _

The third year (FY91) will complete the definition phase supported by the discretionary

fund. All sponsored work should be finished by the end of December 1991. .......

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REFERENCES

0 Gooding, J. L.: Differential scanning calorimetry (DSC) and evolved-gas analysis

(EGA) applied to planetary surface exploration. In I. R. Harrison (Ed.), Proc. 18th

North American Thermal Analysis Society (NATAS) Conference, vol. 1, 1989, pp.

222-228.

. Gooding, J. L.: Thermal Analyzer for Planetary Soils (TAPS) experiment: Functions

and design options. To appear in Lunar and Planetary Science XXII, Lunar and

Planetary Institute, Houston, Texas, March 1991.

, Allton, J. H.; Lauer, H. V. Jr.; Draper, K J.; and Gooding, J. L.: Thermal Analyzer for

Planetary Soils: Results of Initial Testing of Mark-1 Sample Probe Prototype. JSC

24572, NASA Johnson Space Center, Houston, Texas, 1990, pp. 1-16.

0 Gooding, J. L.; and Allton, J. H.: Water/rock interactions in carbonaceous chon

drites: Possible fingerprints for in-situ comet-nucleus analysis. To appear in

Lunar and Planetary Science XXII, Lunar and Planetary Institute, Houston,

Texas,March 1991.

5. Gooding, J. L.; Kettle, A. J.; and Lauer, H. V. Jr.: DSC signatures of water-bearing

geologic materials relevant to Mars and comets. In I. R. Harrison (Ed.), Proc. 19th

North American Thermal Analysis Society (NATAS) Conference, vol. 1, pp. 9-15.

. Gooding, J. L.; Kettle, A. J.; and Lauer, H. V. Jr.: DSC sensitivity to hydrated miner

als in planetary samples. To appear in Lunar and Planetary Science XXII, Lunar

and Planetary Institute, Houston, Texas, March 1991.

33
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Heat sample to epel gases

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analyzer

• Indentify gaseous species

• Measure concentrations

Indentify minerals or ices

(and their abundances)

by thermodynamic response

o Purgesample residue

• Water

Carbon, nitrogen,

and sulfar compound

Figure I7.

X 100466M

TAPS functional diagram (experiment functions).

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Thermal Analyzer for Planetary Soils (TAPS)

Bench-level tests of piezoelectric water sensor

(9 MHz quartz oscillator with Peltler cooler).

Temperature (K) Temperature (K)

280 290 300 280 290 300

8998.3 I I 8998.3 j _ I I

r.o .,r--"L "

i 8998.1 J Apparent

8998.0 J-- dewpoint

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8998.1 I I I I 8997.6

40 50 60 70 80 40 50 60 70 80

Temperature (F) Temperature (F)

X100467M

Figure 18. Experimentally determined DSC sensitivities.

35
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Thermal Analyzer for Planetary Soils (TAPS)

DSC detectablility of hydrated minera!s in basalt matrix.

• Analyses made in JSC Thermal Analysis and Calorimetry Laboratory (TACL)

° DSC-2C instrument operated at 10 K/min and 5 cc Ar/min; no cold sink

• Enthalpy of dehydration (relative to pure phase); 1 std. dev. from 3 analyses

• Ordinary data analysis (without benefit of deconvoluti0n anaysis)

• Conclusion: Sensitivity at least 0.5 wt. % (equiv. 0.1 wt. % water for gypsum)

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Figure 19. Experimentally determined response of a candidate solid-state TAPS water

sensor to cooling below dewpoint (left) and sudden exposure to a pulse of humid air

(right), as simulations of evolved-gas analysis.

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Thermal Analyzer for Planetary Soils (TAPS)

• Work performed at JSC (> 120 individual tests)

• Test material: Cheto (Arizona, USA) bentonite (crushed and sieved)

• Variables: particle size, sample packing density, speed (rpm) of rotary paddle

• Conclusions: Performance in sand acceptable; redesign needed for silt

SAND (125-250 pm)

1.01 g/cm3

- o_ 98 rpm

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2 4 6 8 10

Test number

6

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- I

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v v v '_ v ,_ ,!_ v

0 2 4 6 8 10 12 14

Test number

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Figure 20. Experimentally determined sample-acquistion performance of the TAPS

Mark-1 sample probe which is based on a spinning-paddle design.

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TITLE OF INVESTIGATION: Lymphocyte Activation in Simulated Microgravity and

PROJECT MANAGER: Clarence F. Sams, Ph.D./$D4/483-7160

INITIATION YEAR: 1989 "

FUNDING: Total prior years FY90

In-house: 50k 35k

Contractors: : 0 0

Grants: 0 0

Total funds: 50k 35k

OBJECTIVE

A decrease in mitogen-induced activation has been observed in vitro with peripheral

lymphocytes during space flight or in clinostats. This decreased activation may be due

to alterations in cellular signaling or to environmental changes in the hypogravity cell

culture environment. The focus of this basic research activity is to determine the molecular and cellular mechanisms responsible for the apparent gravity sensitivity of

lymphocyte activation previously reported for cells in culture. This major objective has

been reduced to the following specific tasks: (1) to characterize potential alterations in

the cell culture environment as a function of gravity, (2) to determine the response of

Iymphocytes to these environmental alterations, and (3) to examine the cellular and

molecular mechanisms involved in these responses. The influence of the cell culture

environment on lymphocyte function in vitro will be evaluated with particular emphasis on those aspects which are changed in nonunit gravity. The events associated with

the activation process, such as cell-cell communication, cell signal transduction, and

alterations in transcriptional and synthetic activity will be examined to assess their

relative contribution to gravity-induced changes in lymphocyte responses.

These studies will provide basic information concerning the impact of gravitational

changes on specific cellular functions and will provide the preliminary data supporting

development and submission of an original research proposal.

ACCOMPLISHMENTS IN FY90

The initial characterization of the cell culture environment in simulated microgravity

was performed in FY89 using a lymphocytic cell line (SP2 from the American Type

Culture Collection) and a JSC cell culture dinostat (slow turning lateral vessel). These

experiments indicated limitations in metabolic transfer as well as apparent alterations

38

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in cellular response. The environmental limitations were examined and a redesigned

vessel was produced which provided improved gas exchange. Metabolic support of

high-density cell cultures was possible with the new vessel, though the persistence of a

lag phase upon inoculation in the vessel suggested the influence of ceil-cell contact in

the growth response of this cell line. A patent application for the redesigned culture

vessel (high aspect ratio vessel) was filed in FY90. These studies represent collaborative

efforts between the Biotechnology Labs and the Cell Image Analysis Lab of the Medical

Sciences Division.

The observations with the cell lines suggested that the effective cell concentration in the

suspended state may also have an impact on mitogen-induced activation of peripheral

lymphocytes. Lymphocytes were treated with various mitogens while suspended by

gentle mixing or while static. Activation was followed by the appearance of CD69

protein. CD69 appears on the surface of activated lymphocytes within 2 hours after

treatment with mitogens and represents the earliest surface activation marker. A

significant decrease in CD69 expression was observed for suspended lymphocytes

activated with the surface active mitogen phytohemagglutinin (PHA) as compared to

cells activated in static culture (fig. 21). Activation with a phorbol ester, which bypasses the cell surface receptor mediated events and directly activates intracellular

signaling pathways, resulted in equivalent activation of suspended or static cells. These

findings indicate simple dispersion of cells may play a significant role in the response of

cells to culture in microgravity. In addition, these data demonstrate the utility of using

different mitogens to isolate specific processes or functions in the activation cascade.

PLANNED FUTURE WORK

The results to date suggest that the initial events in lymphocyte activation are influenced by alterations in cell culture environment similar to those occurring in nonunit

gravity. Further studies will examine the early responses in the activation cascade to

determine the molecular mechanisms influenced by gravity. Specific experiments will

examine the function of the intracellular signaling pathways including the inositol

phosphate second messenger system, changes in intracellular calcium concentration,

and the activation and translocation of protein kinase C. In addition, the role of cellular

adhesion receptors in the initial cell surface events will be explored. Changes in transcription of cellular oncogenes associated with activation/proliferation (such as c-myc

and c-fos) will be quantitatively determined. The role of the cell cytoskeleton in the

integration of these molecular responses will be evaluated.

EXPECTED COMPLETION DATE: 1991

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Figure 21. Activation of lymphocytes. Lymphocytes were activated with 2_t/ml phytohemagglutinin for 24 hours in sealed tubes

which were static (PHA) or placed on a blood rocker to gently

suspend cells (s-PHA). Activation was measured by the percentage of CD69 positive cells as determined by immunofluorescent

labeling and flow cytometry. Data area presented as percent

CD69 positive ceils vs. time after mitogen addition.

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TITLE OF INVESTIGATION: Plasma Volume and Orthostatic Tolerance

PROJECT MANAGER: Suzanne M. Fortney, Ph.D/SD5/37213

INITIATION YEAR: 1989

FUNDING:

In-house:

Contractors:

Grants:

FY89 FY90

60k 60k

0 0

50k 50k

m m

Total funds: 110k 110k

OBJECTIVES

Hyatt and West (ref. 1) have shown that 4 hours of continuous exposure to -30 mm Hg

lower body negative pressure (LBNP) and the simultaneous ingestion of 1 liter of an

isotonic salt solution will restore plasma volume and orthostatic responses for up to 18

hours during bed rest. The objective of this project is to develop the optimum protocol

(LBNP profile and fluid loading solution) which restores plasma volume and orthostatic

responses with a minimum time commitment, discomfort, and risk.

FLUID SOLUTIONS

An effective fluid solution must expand plasma volume for at least 24 hours during

simulated weightlessness (bed rest) and result in an improvement of orthostatic responses. The solution must be palatable. Plain water and weak salt solutions or solutions containing glucose have been found to stimulate a diuresis with only transient

expansion of plasma volume and no improvement of orthostatic responses. Riedesel et.

al. (ref. 2) have demonstrated the ability of glycerol when added to water, to cause fluid

retention without provoking a diuresis. Glycerol promotes fluid movement across cell

membranes, resulting in fluid retention. However, fluid retention occurs in all fluid

compartments of the body, not just the plasma volume. One goal of this proposal is to

determine whether glycerol ingestion during bed rest will significantly expand body

fluids and improve orthostatic responses to a greater degree than isotonic saline. (This

part of the study is being performed in Albuquerque, New Mexico by Dr. Riedesel with

extended duration orbiter funding.)

41
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LBNP EXPOSURE

Although the 4-hour LBNP protocol of Hyatt and West (ref. 1) has been demonstrated

to effectively improve orthostatic responses for up to 18 hours, this protocol is very

cumbersome to perform inflight. It was recently flown during th_ _3_2_m]ssfon_d _

was reported to cause considerable subject discomfort as well. This flight LBNP treatment protocol is shown in figure 22. One objective of this study is to modify the negative pressure profile to allow equal improvement of orthostatic responses during bed

rest in less time - a total daily exposure duration of less than 2 hours. Exposure to a

fluctuating pressure profile rather than a continuous profile at -30 mm Hg, is thought to

be more efficient in provoking fluid retention and cardiovascular responses which may

result in improved orthostatic responses.

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ACCOMPLISHMENTS IN 1990

Completion of a bed rest study in 10 male subjects with duel objectives to, first,

validate the effectiveness of a 4-hour continuous -30 mm Hg LBNP profile and

simultaneous ingestion of 1 liter of isotonic saline to restore plasma volume and

orthostatic responses during bed rest. Second, to determine whether this LBNP and

fluid ingestion protocol may be shortened to 2 hours and remain effective in restoring orthostatic responses. The 4-hour protocol was validated in this ground-based

study and found to still be effective 24 hours after treatment. The 2-hour profile

expanded plasma volume but was not effective as a countermeasure for orthostatic

intolerance 24 hours after treatment.

A second bed rest study of female subjects to determine, first, whether the 4-hour

continuous -30 mm Hg LBNP and isotonic saline treatment will be as effective in

women as it was shown to be in men. Second, a 2-hour sinusoidal LBNP profile

(LBNP pressure continuously fluctuating between 0 and -60 mm Hg once each

minute) and simultaneous ingestion of I liter of isotonic saline was tested as a countermeasure to restore orthostatic responses during bed rest. The 4-hour treatment

improved orthostatic responses in only 3 out of 8 of the first eight women studied.

Likewise, the sinusoidal LBNP profile improved orthostatic responses in only 3 of

the eight subjects tested so far.

APPLICATIONS MADE OF INVESTIGATORS RESULTS DURING FY90

The results from the study of the male subjects was used to finalize the LBNP protocol

used in STS 32 as shown above. The LBNP profile flown was the full 4-hour, 30-mm Hg

continuous LBNP and saline countermeasure.

PATENTS

N/A

REPORTS, JOURNAL ARTICLES, OTHER PUBLICATIONS

• Fortney, S.M. and Cintron, N.M. Plasma volume and orthostatic tolerance. Center

Director's Discretionary Fund, Research and Technology Report, 1990.

Fortney, S.M. Development of lower body negative pressure as a countermeasure

for orthostatic intolerance. Submitted to the Journal of Clinical Pharmacology,

1990.

Fortney, S.M.; Dussack, L.; Rehbein, T.; Wood, M.; and Steinmann, L. Effect of

prolonged LBNP and saline ingestions on plasma volume and orthostatic

responses during bed rest. Conference Report from the Joint ARC/JSC Cardiopulmonary Workshop, December 6 and 7, 1990.

43
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PAPERS FOR PRESENTATION AT PROFESSIONAL SOCIE_MEE_GS _

• Bondar, R.L.; Kassam, M.S.; Stein, F.; Dunphy, P.T.; Fortney, S.; and Charles, J. The

usefulness of transcranial doppler in predicting loss of orthostatic tolerance during lower body negative pressure. Abstr. submitted to Aerospace Medical Asso

ciation Meeting, 1991.

• Fortney, S.M.; Troell, M.; Dussack, LI; and Cintr0n, NIM. Plasma voiume, fluid

balance, and endocrine responses to prolonged lower body negative pressure

(LBNP) during bed rest. Abstr. submitted to Federation of Experimental Biology

and Medicine Meeting, 1991.

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PLANNED FUTURE WORK

• Finish female bed rest study. (Two more subjects expected to be tested January 31,

1991 until February 16, 1991.) Data analysis and manuscript preparation for rest of

the year.

• Perform short, 7-day bed rest study in men to evaluate the effectiveness of sinusoidal LBNP 2-hour protocol in men. (Begin this summer.)

EXPECTED COMPLETION DATE

Studies completed by October 1, 1991.

Data analysis and manuscript preparation done by October 1, 1992.

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REFERENCES

0 Hyatt, K.H.; and West, D.A.: Reversal of bedrest-induced orthostatic intolerance by

lower body negative pressure and saline. Aviat. Space Environ. Med. 48: 1977,

pp. 120-124.

. Lyons, T.P.; Riedesel, M.L.; Meuli, L.E.; and Chick, T.W.: Effects of glycerol-induced

hyperhydration prior to exercise in the heat on sweating and core temperature.

Med. Sci. Sports Exercise 22: 1990, pp. 477-483.

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TITLE OF INVESTIGATION:

PROJECT MANAGER: Millard F. Reschke, Ph.D./SD5/483-7210

Neural Network Modeling of Postural Control

TEAM MEMBER: James A. Villarreal

INITIATION YEAR: FY89

FY89 FY90

In-house: 15k 15k

Contractors: 15 35

Grants: 0 0

Total funds: 30k 50k

FUNDING:

OBJECTIVE

The goal of this project is to develop a neural network (NN) model of postural equilibrium control that can map sensory input signals from the visual, vestibular, and proprioceptive systems into appropriate motor control strategies for maintenance of stable,

upright stance. When the model is sufficiently developed, it will be trained using preand postflight postural equilibrium data to simulate the course of neurosensory adaptation to microgravity and readaptation to the terrestrial environment. It may then be

useful in predicting untoward responses to normal crew activities and aid in developing appropriate countermeasures to these responses.

ACCOMPLISHMENTS

The following is a brief summary of the significant work performed during FY90. For

more details consult the Center Director's Discretionary Fund Final Report "Neural

Network Modeling of Postural Control" published November 30, 1990, which is available upon request.

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Methods

The project focused on analyzing posture data obtained from 10 normative subjects who

spent 30 minutes in the Tilt Translation Device (TFD), which is one of several preflight

adaptation trainer (PAT) simulators available in the Johnson Space Center (JSC) Neurosciences Laboratory. The PAT devices were designed to produce a sensory conflict

similar to the conflict caused by microgravity. The TI_D operates by presenting a visual

scene to a subject which can be translated back and forth and by tilting the subject

forward and backward. The TTD generates a sinusoidal tilting and translation motion

45
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with an adjustable phase lag between the separate motions. Previous studies have

revealed that exposure to microgravity generates a sensory conflict which the central

nervous system attempts to resolve by reinterpreting tilt as translation. The subjects

underwent a battery of posture sensory organization tests (SOTs) using a commercially

available posture platform, before and after exposure to the TFD (fig. 23).

To perform the analysis, an NN architecture was chosen that was especially suitable for

the task. The spatiotemporal neural network (STNN) is a variant on the well known

backpropagation (BP) algorithm. The BP algorithm is used in multilayered

feedforward networks and works via supervised learning; i.e., the network is presented with input/output (I/O) pairs in which the network is trained to produce the

output. The training consists of adjusting weights between neurons in different layers

to satisfy a minimum training error criteria. The STNN architecture was conceived by

the Software Technology Branch at JSC to address the task of analyzing several channels of time series data simultaneously. The STNN architecture and learning rule are

very similar to BP; the only real difference is that in place of a single scalar weight

between two neurons, there is now a vector of weights. The components of this weight

"vector" consist of adjustable coefficients similar to those in a digital filter with "pole"

and "zero" coefficients available. In addition to the coefficients, the network contains

delays which store samples of the time series so that one has a "history" of the time

series "spread out" between the network layers (fig. 24).

Pre- Post-PAT Prediction Using Heteroassociative Mapping

The rationale for mapping pre to post PAT data was to find out if it was possible for a

neural network to be used to predict the performance of a subject for a given sensory

test after exposure to the PAT TTD. The implication being that if a network, using only

minimally processed subject data, could capture the essential changes inherent between

the pre- and post-PAT data and successfully generalize to new data, a basis for predicting postflight astronaut performance would exist.

In previous prediction tasks using BP NNs, typically a single-channel time series was

used in which a portion containing a "sufficient" number of samples was mapped on to

the input layer and the network attempted to predict the next sample which was generated by a single output unit. The criteria for knowing how many samples were "sufficient" was dependent on the characteristics of the data. The network was trained by

using a large (about 7/8) portion of the data set in this incremental fashion. The trained

network was tested on the remaining portion. While this method has worked well for

single-channel time series, extensions to the multiple channel case would be difficult

using BP. Also, for our purposes, this prediction method (which could have been

implemented on STNN) would have dubious utility since we required the network to

represent a change brought on by sensory rearrangement. Taking pre-PAT data and

using it to predict future samples of data based on a pre-PAT sensory condition would

not be valid for predicting post-PAT responses,

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We decided to construct I/O pairs by taking the 1st trial of pre-PAT data and pairing it

with the 1st trial of post-PAT data for SOT #6. While it can be argued that there was not

a functional relationship between the two trials per se, the PAT TTD produces a sensory

rearrangement that is fairly robust (based on the comparison of pre- and post-center of

gravity (CG) sway) for a short duration after T'FD exposure. Since the STNN (and BP as

well) performs a mapping from the input data to the output data, it seemed a reasonable idea that a net trained on pre- and post-PAT I/O pairs could deduce the functional

relationship between the two states (based solely on the data) and reproduce it for an

arbitrary input. Two different treatments were done; the first used all 11 channels of

filtered raw data (fig. 25) and the second used derived CG sway data only.

The result for the 11-channel case was that the network reproduced the training set

fairly accurately but did not perform as well on the test set. Average training errors

were I to 2 percent while average testing errors were in the 13 to 15 percent range. The

number of hidden units were varied from 6 to 50 without significant change in the

results. A 6-hidden unit, 5-second window version failed to produce significantly

different results. Another series was run using Subject #2 data only and produced

similar results. A network that performs this way is experiencing some degree of generalization failure. Ideally the network test error would be identical to the training error;

however this target is not easy to attain when real data is used. The network was able

to learn the training set (which usually occurs), but for one of several reasons could not

generalize at an optimum level.

The CG sway data was generated by taking the four force transducers under the support surface and, based on a formula provided by the posture platform manufacturer,

combining these channels into a single channel which measures CG sway over time.

Longer time windows were tried for this portion of the study since it was anticipated

that longer duration training samples and windows would result in better network

performance. The testing error results were comparable to the 11 channel version,

although training error was higher for CG version (8 percent). A three subject version

was tried and had better training error but worse testing error. This version was also

tried with Subject #2 alone and produced a training error of 7 percent and test error of

12 percent. Our goal was to get the error close to the same level as the autoassociator

network. Again, a degree of generalization failure existed. Compared to other NN

pattern recognition and classification tasks found in the literature where biological

experimental data was analyzed, our test data error percentages were comparable.

However, the performance of the network is not yet adequate to justify its use as a

prediction tool for postflight postural responses.

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Hidden Unit Analysis of Autoassociated CG Data

Another method _we tried which has shown promise is to perform an analysis of the

hiddenunits of a trained au_toassociatiye (identical input and output) NN. The network

is trained with a data set until its error is at an acceptable level, at which point the

weights are fixed. The network is then input with the training set again, but instead of

47
changing the weights, the activation values of the hidden units are recorded for each

member of the training set. The justification for this procedure is that the hidden units

generate an internal representation of the mapping between input and output spaces.

By examining the hidden units activation patterns as different members of the training

set are input, some insight can be gained into how the network is performing the mapping. If the activations cluster in this space for similar data, a basis for classification

and/or discrimination may exist. The activations of the hidden units are typically

displayed (for 2 and 3 hidden units) in 2- and 3-dimensional graphs where each hidden

unit's activation level is represented on one axis in the plot. Higher numbers of hidden

units (greater than three) are usually analyzed with attendant loss of visualization (and

insight).

We used an autoassociator of CG data from two sensory tests at the opposite extremes

of the posture testing battery, SOT #1 and SOT #6 (fig. 23). Discriminating between the

two extremes should be the easiest task the NN has to perform. Two different network

architectures, STNN and BP, were used for this experiment. This was done to provide

a point of comparison and, in part, because BP hidden unit analysis is better understood

than its STNN counterpart. In the case of STNN, a 200-point trajectory was generated

representing the duration of the training sample (i.e., 20 seconds). The BP will map the

200-point sample across the input and output layers. Since there is no temporal history

in a BP net, only a single point will be generated for each training sample. In both cases,

three hidden units were used (for ease of visualization) and all members of the training

and test sets were 20 second trials of SOT #1 and SOT #6.

The STNN results revealed easily distinguishable differences between SOT #1 and SOT

#6 based on gross features of the trajectories. SOT #1 had a very small trajectory relative to SOT #6. A feature common to all STNN versions of the autoassociator was an

initial trajectory appeared that was subject dependent (but similar across subjects)

which later developed into a quasielliptical trajectory pattern for the remainder of the

sample. The STNN results for a single subject in which the network discriminated

between three distinct Clrasses of data also revealed differences between the three trials

based on gross features of the trajectories (fig. 26).

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The BP version for SOT #1 and SOT #6 behaved rather closely to expectations as definite clustering occurred and the clusters and locations seemed reasonably consistent.

The plot shown is two dimensional since the activation of the third hidden unit was

very small relative to the other two, hence it was suppressed as it supplied no useful

information. All the SOT #1 trials (odd numbers on the graph) had partial activations

of both hidden units, while the SOT #6 trials (even numbers) tended to ride the axes, the

exception being data point #4 (fig. 27). Why this deviation occurred is unknown.

Based on the results that we had obtain_ from the FYg0 work, we felt some promising

lines of research were discovered and that the appropriate mechanism for continuing

the work would be under the aegis of RTOP funding (see below). A DDF Final Report

has been prepared for submission to t'neNew Initiatives Office and is a-tt/tched to this

technical summary. The report contains more detailed information regarding the work

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performed and discussion of the results obtained.

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PLANNED FUTURE WORK

After evaluating the DDF work results, we feel that the most promising line of research

is to pursue the classification task. NNs will be developed to perform explicit classification of posturai sway data into distinct states based on the standardized posture sensory tests and distinct physiological states that are known to be represented in the data.

Our expectation is that NN-based classifiers should have sufficient discriminative

ability to allow the use of a previously trained network to classify new data obtained

from either normative or astronaut populations.

A spinoff benefit of this research would be the development of a basis for automated

classification of postural sway of clinical patient populations using NNs. Since patients

with various CNS lesions display distinct alterations in postural control which appear

in posture platform testing, NN-based classifiers trained on patient data should perform

as well as NN posture classifiers trained on normative and astronaut populations.

Discrimination of distinct postural control states is more challenging in normative

(versus patient) populations since the variation in performance is smaller; hence, the

NN algorithms, which are successful with normative subjects, should be able to spot

these changes in patient populations.

We are presently in the beginning stages of writing an RTOP proposal to pursue the

development of NN-based posture maintenance classifiers. This research effort would

focus on evaluating the classification performance of several NN architectures applied

to the PAT posture data. An integral part of this effort would also involve analyzing

the network's operation as it performed this task. By understanding what features the

network used to classify the data, we hope to gain some insight into underlying physiological mechanisms that generated the data. This information should aid in achieving

the goals stated in the objective.

EXPECTED COMPLETION DATE

The DDF phase of this project was completed on November 30th, 1990.

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Sensory Organization Test conditions. The symbols on the right

indicate the visual, vestibular, and ankle proprioceptive senspory inputs used

during that test condition. Sway referenced conditions are those in which the

visual surround and/or support surface are directly servo controlled to body

sway thereby providing orientationally inaccurate information. (Figure copyright by Neurocom, Inc.; used with permission.)

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b) Representation of STNN emphasizing the weight vectors interconnections

between layers of processing elements.

Figure 24. STNN architectural features; in both cases note the mapping of input time

series to output time series.

51
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Note that (for clarity) each weight vector is represented by a single line and that

the number of hidden units is variable as described in the text.

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trained with subject #2 SOT #1, SOT #6 (pre-PAT), and SOT #6 (post-PAT) data only.

Note the 200-point trajectories in each case.

a) Composite plot. b) SOT #1. c) SOT #6 (pre-PAT). d) SOT #6 (post-PAT).

53
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values for network trained with SOT #1 and SOT #6 (pre-PAT)

data for five subjects. Note distinct clustering and segregation

of data points.

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TITLE OF INVESTIGATION:

Analysis of Planetary Surface Materials

Backscatter Mossbauer Spectroscopy (BaMS) for

PROJECT MANAGER: Richard V. Morris/SN2/FTS 525-5040

FY89

Total prior years

In-house: 18k

Contractors: 0

Grants: 12

Total funds: 30k

INITIATION YEAR:

FUNDING: FY90

30k

0

30k

OBJECTIVES

Spacecraft missions with landers to the Moon, Mars, asteroids, and other solid solarsystem objects require instrumentation for analysis of surface materials. Analysis

provides characterization of the surface materials and, for sample return missions, a

basis for selection of representative samples. Operation of a lunar base requires similar

instrumentation for in situ resource utilization. Iron Mossbauer spectroscopy is specific

for the element and sensitive to its oxidation states and chemical environment. The

technique provides quantitative information on the mineralogy of iron-bearing phases

and on the relative proportions of those phases. On the Moon, for example, it is an

ideal probe for the mineral ilmenite, which is a source of 02 for life support and He3 for

nuclear fusion. Because of this high selectivity to mineralogy, the inherent simplicity of

the instrumentation, and no requirements for sample preparation, a BaMS (fig. 28) is a

highly viable candidate for inclusion on a surface lander. This project is to (1) document that BaMS can provide the necessary mineralogical data (proof-of-concept) and (2)

build a brassboard instrument. Technology development areas for brassboard subsystems include miniaturization of the velocity transducer, incorporation of solid-state

detector, and testing of detector arrays (both solid state and proportional counter). This

project is the basis for proposals to the Planetary Instrument Definition and Development Program for full development of a flight instrument. The project is conducted by

the Solar System Exploration Division of the Johnson Space Center.

ACCOMPLISHMENTS IN FY90

For the proof-of-concept phase of the project, a research-grade Mossbauer spectrometer,

capable of operation in both the normal transmission mode and in backscatter mode,

was obtained during FY89. Analysis of samples pertinent to planetary applications of

Mossbauer spectroscopy is underway. Transmission Mossbauer spectra for a martian

meteorite, a palagonitic soil (an analogue of weathered martian material), and a lunar

55
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simulant are shown in figure 29. The sensitivity of the technique to iron mineralogy is

clearly apparent. Computer programs have been developed to parameterize the

Mossbauer spectra. For the brassboard phase of the project, a piezoelectric (PZ) velocity

transducer was tested as an alternative to the bulky and heavy velocity transducer

present in laboratory systems. A miniaturized version of a conventional velocity transducer is also being constructed. A list of publications and talks associated with this

project are listed in the bibliography.

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PLANNED FUTURE WORK

Samples appropriate to martian and lunar applications of a BaMS instrument will

continue to be analyzed. Several velocity transducer designs (PZ and conventional) will

be completed and competed against each other. Detector arrays will be built and tested.

A brassboard instrument employing optimum detector and transducer designs will be

built and tested.

EXPECTED COMPLETION DATE

September 30, 1991.

BIBLIOGRAPHY

1. Morris, R.V.; Agresti, D.G.; Shelfer, T.D.; and Wdowiak, T.J.: Mossbauer backscatter

spectroscopy: A new approach for mineralogical analysis on planetary surfaces.

In Lunar and Planetary Science vol. XX, The Lunar and Planetary Institute, Houston, 1989, pp. 723-724.

2. Agresti, D.G.; Wills, E.L.; Shelfer, T.D.; Iwanczyk, J.S.; Dorris, N.; and Morris, R.V.:

Development of a solid-state Mossbauer spectrometer for planetary missions. In

Lunar and Planetary Science, vol. XXI, The Lunar and Planetary Institute, Houston,

1990, pp. 5-6.

, Morris, R'.V.; Gooding, J.L.; Lauer, H.V.; and Singer, R.B.: Origins of Marslike spectral and magnetic properties of a Hawaiian palagonitic soil. J. Geophys. Res. 95,

1990, pp. 14427-14434.

.

Shelfer, T.D.; Pimperl, M.M.; Agresfi, D.G.; Wills, E.L.; and Morris, R.V.: Backscatter Mossbauer spectrometer (BaMS) for planetary applications: Transducer

design considerations. In Lunar and Planetary Science, vol. XXII, The Lunar arid- ....

Planetary Institute, Houston, accepted, 1991.

5. Agresti, D.G.; Shelfer, T.D.; Pimperl, M.M.; Wills, E.L.; and Morris, R.V.: Mossbauer

spectrometer for planetary surfaces, Am. Phys. Soc. An. Mtg., accepted, 1991.

56

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Figure 28. Transmission Mossbauer spectra.

57
Electronics

Piezoelectric translator

and gamma ray source

Solid state detectors

X 100509M

Figure 29. Backscatter Mossbauer spectrometer (BaMS).

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TITLE OF INVESTIGATION: Regenerative Life Support Systems (RLSSs)

Test Bed Project

PROJECT MANAGER: Albert F. Behrend/EC3/483-9241

PRINCIPAL INVESTIGATOR: Donald L. Henninger/EC3/483-5034

PROJECT ENGINEER: Terry O. Tri/EC3

INITIATION YEAR: FY90

FUNDING: Total prior years FY90

In-house: 0 283k

Contractors: 0 17

Grants: 0 0

Total funds: 0 300k

FY91 (est.) FY92 (est.)

300k 400k

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OBJECTIVE

The objective of the RLSS Test Bed Project is to use higher plants grown in a closed,

controlled environment in conjunction with physicochemically based life support systems to provide an integrated biological/physicochemical RLSS test bed. A human

metabolic simulator, or "canned man," also will be integrated into the test bed, which

will supply variable metabolic loads to the system to simulate the presence of a crew.

The integrated RLSS test bed will be fully automated to grow crops from seed to harvest

without the need for human intervention. One of the test bed's two growth chambers

(see fig. 30) will be operable at both ambient and reduced atmospheric pressures to

more closely duplicate candidate lunar and martian habitat environments ( ref. 1).

Major objectives of the test bed include quantification of life support capabilities of

higher plants (i.e., oxygen production, carbon dioxide uptake, and water conditioning

via transpiration), determination of interactions between the biological and physicochemical life support system components, and definition of the integrated control

system approach for providing variable life support capabilities on demand. Data from

the RLSS Test Bed Project will be used to define requirements for a future human-rated

RLSS test facility to be developed at JSC (ref. 2).

ACCOMPLISHMENTS IN FY90

The RLSS Test Bed Project achieved several key accomplishments during FY90, including development of an overall systems design for the test bed and outfitting the variable

pressure growth chamber with plant growth systems. The chamber outfitting activities

consisted of constructing an internally-located atmospheric conditioning system, a

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fluorescent lighting system, four independent fluid delivery systems for deionized

water irrigation and nutrient solution delivery, and various other supporting subsystems. Other key activities accomplished in FY90 included constructing the ambient

pressure growth chamber, outfitting a centralized control room for monitoring and

control of the test bed, and developing an initial supporting research laboratory in

which off-line plant growth experiments and biomass production analysis can be

peformed.

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PLANNED _RE WORK

Anticipated FY91 accomplishments include performing functional testing of the existing

plant growth systems, growing several test crops of lettuce and wheat in various solid

support substrate media, outfitting the ambient-pressure growth enclosure with hydroponically-based plant growth systems, fabricating the metabolic simulator, and preparing an existing physico-chemical air revitalization system for eventual integration into

the test bed.

EXPECTED COMPLETION DATE

The Center Director's Discretionary Fund (CDDF) portion of this project is scheduled to

be completed in October 1992 (i.e., 3 years of CDDF support). After this date, continuation of this project is anticipated to be funded by the Research and Technology Objectives and Plans program. +

REFERENCES

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Henninger, D. L., et al.: Regenerative Life Support Systems (RLSS) Test Bed Performance Character_z_ti0n of Plant Perf6rmahce inaUlodeK ontro+lled Test Cha_m -+

ber. To be presented at the 21st Intersociety Conference on Environmental Systems, Society of Automotive En_neers_ 199 ! (in work).

Tri, T. O., et al.: Regenerative Life Support Systems (RLSS) Test Bed Develop me+n+t at

NASA Johnson Space Center. To be presented at the 21st intersociety Conference on Environmental Systems, Society of Automotive Engineers, 1991 (in

work).

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Figure 30. The RLSS Test Bed Facility layout.

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TITLE OF INVESTIGATION: Mockup of a Constructible Lunar Habitat

PROJECT MANAGER: Michael Roberts/ET2/483-6632

INITIATION YEAR: FY90 .......

FUNDING: Total prior years FY90

In-House: 0 135k

Contractors: 0 0

Grants: 0 0

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OBJECTIVE _

The Center Director's Discretionary Fund (CDDF) activity will result in the construction

of a full-scale mockup of a construcfibie lunar habitat. The near-term goal of the project

is to evaluate the habitability of a 10-m spherical habitat. The long-term goal is to develop a facility for the rapid creation and modification of habitat mockups, so that

architectural trade studies in support of the Space Exploration Initiative may be performed in a timely manner.

ACCOMPLISHMENTS IN FY90

A modular structural framework has been procured. The framework is currently

configured as a four-story hexagonal cylinder, 38 ft tall and 36 ft in diameter. This

framework is designed for rapid assembly and disassembly, and may be reused to

support other habitat or vehicle mockup configurations.

A complete interior design for a 10-m diameter spherical habitat has been completed. This design was performed by a team of four university space research

associate students under the direction of NASA personnel. The design is documented in a report titled, "Design of an Inflatable Habitat for NASA's Proposed

Lunar Base" (see ref. 1).

The funding for this project was shared with another CDDF project, a mockup of

an initial lunar habitat. This second project was directed by SP personnel and is

the subject of another report item.

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PLANNED FUTURE WORK

The actual construction of the mockup interior elements and external cover are underway, with completion expected in early 1991. The resulting spherical configuration will

be evaluated by such architectural criteria as efficient utilization of space, available

stowage, and ease of movement within the habitat. The evaluation will be documented

in a report.

A vertical cylindrical habitat configuration has been proposed as a follow-on study.

Construction of the follow-on is expected to begin in the fall of 1991.

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EXPECTED COMPLETION DATE

May 1991

REFERENCES

1. Connell, R. B., et. al.: Design of an Inflatable Habitat for NASA's Proposed Lunar

Base. August 1990.

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TITLE OF INVESTIGATION:

Neural Net with Stereo Vision input

Adaptive Control of a Robot Arm Using an Artificial

PROJECT MANAGER: Timothy F. Cleghorn, Ph.D/PT4/483-8090

ASSOCIATED PROJECTS: Leo Monford/IC

Les Theard/LEMSCO, Texas A&M University

FY90

Contractors:

Total funds:

INITIATION YEAR:

FUNDING:

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Total prior years FY90

0 50k

0 50k

OBJECTIVE

Development of artificial neural net techniques for the adaptive control of robot arms.

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ACCOMPLISHMENTS IN FY90

The mode of operation currently proposed for space and planetary surface robotics is

teleo-peration. While this may prove satisfactory for tasks in the immediate vicinity of a

manned spacecraft, it is clear that there will be numerous occasions for which more

autonomous robotic behavior will be required. Examples of such tasks include satellite

servicing, for which the transmission time delays are unacceptable; routine inspections,

requiring intense human concentration for long periods, thus raising the probability of

error due to fatigue or boredom; and planetary surface rover operations for which the

round trip transmission times exceed the real time requirements.

Similar tasks have been addressed usually by what can be called "automatic" robotics;

i.e., the arm or vehicle is preprogrammed to carry out a specific operation. It has little

or no sense of its environment, and if an unanticipated event occurs, at best, it shuts

itself off and waits for a human to restart it. What will be needed in order to carry out

the more demanding tasks is the development of "autonomous" robotics in which the

computer attached to the arm or vehicle has a wealth of sensory input about the environment, and the ability to respond to that input without human intervention. The

system thus adapts to the environment, and can continue to function in the face of

unforeseen events or obstacles.

Until recently, there have been two major factors which have limited the development

of autonomous robotics. The first of these was the lack of sufficient computing power.

This is no longer seen as a limiting problem, especially with the advent of parallel

architectures. Even serial computers are now becoming fast enough, and have sufficient memory and storage capabilities to handle some of these problems. The other

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limiting factor was the lack of success of the "classical" artificial intelligence techniques.

Combinatorial explosions usually derailed the attempts to teach computers about their

environments. With the rediscovery and development of artificial neural net technology in the 1980's, this problem is also being addressed. One class of network, adaptive

resonance theory (ART), is particularly suitable for the environment sensing and response problem.

A simulation has been developed on a Silicon graphics computer, which demonstrates

the Robotics Research Corporation K-1607 robot arm learning to reach out and touch a

spherical target object. The learning process occurs with an ART-like net similar to one

developed by Neurogen, Inc. for a microbot arm. The inputs to these networks are

stereo images of the target and arm. There are two phases: a learning phase and a

production phase. During the learning phase, the arm manipulates the target sphere

within the field of view of the cameras, similarly to how a baby observes his or her

hands moving in front of its face. This allows the weights of the neural net to make an

association between the view and the position and motion of the arm. During the

production phase, the target is placed at random within the field of view of the cameras,

and depending upon the degree of learning, the arm reaches out and touches it. Initially, learning occurred quite rapidly. After about 20 000 learning manipulations, the

arm could touch the target in more than half of its attempts. The system continued to

learn less rapidly for up to 200 000 manipulations, at which point it was able to touch a

randomly placed target more than 90 percent of the time. The time needed for 200 000

learning trials was about 10 hours.

This demonstrates the potential for neural network technology for solving problems

involving unstructured or dynamic environments, as are likely to be encountered in

both space and planetary surface robotics operations.

A graphics demonstration was developed and delivered, including source code, which

illustrates a 7-degree-of-freedom robot arm using stereo machine vision as input to its

neural net controller to locate and grapple a target object. The neural network is adaptive and exhibits unsupervised learning.

PLANNED FUTURE WORK

The demonstration will be enhanced and refined to include obstacle avoidance and

additional classes of target objects. The system is written so that the output can be used

to control actual hardware robots. This will be performed for robot arm configurations

of increasing complexity during the period FY91 to FY95. The long-term goal is to be

able to include dynamic targets and obstacles in the neural net controller system.

EXPECTED COMPLETION DATE

The estimated completion date at this time is 1995.

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TITLE OF INVESTIGATION: Psychosocial Support for Long-Duration Missions

PROJECT MANA G ER: Patricia A. Santy, M: D./SD 5 / 483-7111

TEAM MEMBERS: A.W. Holland, Ph.D. and Roy Marsh, M.D.

INITIATION YEAR: 1989

FUNDING: Prior year FY90

35k 32k

OBJECTIVES:

• Review the literature and Soviet data on methods of providing psychosocial

support in various environments.

Develop several operational strategies for psychosocial support for long-duration

space missions: :

• Develop RTOP/operational proposals for future funding

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ACCOMPLISHMENTS

Santy, Patricia A.; Psychosocial Support for Long-duration Space Missions.

Presented at the IAF meetings in Tashkent, USSR, November, 1989.

Santy, Patricia A.; Psychological Health Maintenance on Space Station Freedom.

Journal of Spacecraft and Rockets 199_, vol. 27,pp. 482-85.

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PLANNED FUTURE WORK

Drs. Marsh and Holland are currently working on developing individual support plans

for extended duration orbiter missions. Funding for this ac_v'Vi_ will be comingfrom

medical operations.

EXPECTED COMPLETION DATE

This project is ongoing.

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TITLE OF INVESTIGATION: Evaluation of New Body Composition Techniques

in Variable Gs

PROJECT MANAGER: Steven F. Siconolfi, Ph.D./SD5/483-7110

INITIATION YEAR: FY89

FUNDING: Total prior years FY90

In-house: _ 35k 32k

Contractors 0 0

Grants 0 0

Total funds: 40k 30k

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OBJECTIVES:

Development of new methodologies that can measure changes in body fluids and lean

mass (muscle) is the cornerstone for evaluating microgravity-induced changes in body

composition.

This project has been divided into four main phases.

Characterize the bioelectrical responses of the body with different skin

temperature, input frequencies, and electrode configurations relative to

body positions (FY89/90).

Data for Phase I and II is currently being collected (25 percent of the subjects

are completed). These phases are examining the relationships between

bioelectrical responses to low voltage, mutifrequency electrical inputs and body

fluid compartments (total body water, extracellular fluid volume, and plasma/

blood volume).

• Phases II and llI include the engineering of a compliance volumometer and

the physiological evaluation of the volumometer.

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ACCOMPLISHMENTS IN FY90

• Completed skin temperature and input frequency analyses.

• National presentations (refs. 1 and 2) of the characterization of the input

frequency responses.

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Input frequency responses evaluated with bedrest (ref. 3).

• Skin temperature analysis abstract accepted for 1991 presentation (ref. 4).

• Started Phases I and II September, 1990.

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PLANNED FUTURE WORK

• Complete Phases I and II by March 1, 1991.

• Complete engineering checkout of compliance volumometer for both pressure

and gas dilution) March 1, 1991 (n=60 subjects. 30 males, 30 females).

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REFERENCES

1. Harris, J.; Smith, R.; Reynolds, M.; and Siconolfi, S.F.: Frequency-resistance

responses for bioelectrical an-ai_Ms inhumans. Aviation, Space and _ _: .... - __

Environmental Medicine (abstract), 1990.

2. Smith, R.; Harris, J.; Reynolds, M.; and Siconolfi, SS.F." Bioelectrical responses

of humans to input frequencies between 50 and 240 kHz. Medical Science

Sports Exercise (abstract), !990.

_ - . -_: _, 7 . ::=-_._,.:i =_ _:_ _v_ . _ _ _,.:_v..-_ = '=._ _ v

3. Wogan, C.F.; Moore, A.D.; Barrows; L.H.; Harris, B.A.; and Siconolfi, S.F.:

Assessing Fluid Shifts with Bioelectrical Resistance During Bedrest.

Aviation, Space and Environmental Medicine, 1990. ......

, Barrows, L'H.; Stricklin, M.D.; and Siconolfi, S.F.: The relationship between _.....

bioelectrical resistance and fat-free mass under conditions of different

frequency, temperature, and time. Aviation, Space and Environmental

Medicine (abstract), 1991.

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PROJECT TITLE : Automated Grappling Control for the Space Shuttle Remote

Manipulator System Utilizing the Magnetic End Effector and the

Targeting and Reflective Alignment Concept (TRAC)

LEADER:

ASSOCIATED PROJECTST:

Timothy F. Cleghorn, Ph.D./PT4/483-8090

INITIATION YEAR:

FUNDING:

FY90

Contractors:

Leo Monford/IC

Les Theard/LEMSCO, Texas A&M University

OBJECTIVE

Total funds:

Prior years FY90

0 50k

0 50k

Automation of the TRAC system using machine vision techniques and development of

similar machine vision techniques for space and terrestrial robotics operations.

ACCOMPLISHMENTS

An Aspex, Inc. PIPE Processor PSI/100 was delivered and installed. Several machine

vision programs were written or ported to this machine. Cooperation set up between

NASA and Texas A&M University for development of machine vision routines for the

magnetic end effector.

PLANNED FUTURE WORK

The long-term goal is the development of a flight demonstration using real-time machine vision techniques and the TRAC system to control grappling by the Space Shuttle

remote manipulator system with the magnetic end effector. Near-term work will include development of demonstrations in the manipulator development facility and

elsewhere of the real-time machine vision techniques. Funds will be used to procure

additional hardware and software to develop and enhance the lab's real-time machine

vision capabilities.

EXPECTED COMPLETION DATE

1997

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TITLE OF INVESTIGATION: Doubly Labeled Water Technique

PROJECT MANAGER: Helen W. Lane/SD4/483-7188

INITIATION YEAR: FY90 I

FUNDING:

In-house: 50k

Contractors: 0

Grants:

Total funds: 50k

OBJECTIVES:

- -__ _ 71 _ _: _b _

To develop a scientifically valid method, doubly labeled water, for determination of

energy requirements during space flight.

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ACCOMPLISHMENTS

• Key accomplishments including reference to:

Built purification systems for hydrogen and CO2 from biological

samples (urine and saliva)

• Reports, journal articles, other publications

Submitted to: Analytical Chemistry

Socki, R.A.; Karlsson, H.R.; and Gibson, E.K.:

A rapid and inexpensive extraction technique for the 0 - 18

determination of water using pre-evacuated glass vials.

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Papers for presentation at professional society meetings, seminars, symposia,

and other important forums ...................

Paper presented at International Congress of Geochemistry and

Geochronology, Canberra, Australia in September 1990.

PLANNED FUTURE WORK

• Validate manifold built to purify hydrogen and oxygen.

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• Use data from flight detailed supplement objective on fuel cells and Orbiter

water to refine in flight doubly labeled water methods.

• Use data to develop models.

EXPECTED COMPLETION DATE

First stage of Center Director's Discretionary Fund completed in 3 years (FY91 - FY92).

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TITLE OF INVESTIGATION: Development of Alloys with Improved Burn

Resistance .....

PROJECT MANAGER: Joel Stoltzfus/RA/FTS 572-5731 ....

TEAM MEMBER: Subhashish Sircar - Lockheed-ESC White Sands Test Facility

INITIATION YEAR: FY89

FUNDING:

In-house:

Other fund sources:

Total funds:

Total prior years FY90

40k 25k

30 150

70-k 1751_

OBJECTIVE

The selection of burn-resistant metal alloys for use in oxygen systems has long been an

important issue for designers of ground support and flight systems. Fires in oxygen

systems are usually catastrophic and may result in loss of hardware and human life.

Recent advances in the testing methodoiogyhave led to the ability to rank metals and

alloys with respect to their flammability in oxygen. However, the alloys that have the

greatest resistance to burning do not always have the best mechanical and physical

properties. This has led to the need to develop new alloys with improved burn resistance and more favorable mechanical and physical properties. The objective of this

project is to develop the technology to formulate and test alloys with these advanced

properties.

ACCOMPLISHMENTS IN FY90

Equipment for formulating new alloys and producing test specimens has been purchased and installed, and 25 elemental metals have been purchased. The alloy formulation facility is being activated. Other sources of funds to supplement this project were

obtained which contributed $150k in FY90. These funds were used to perform most of

the flammability testing discussed below.

Extensive flammability testing of pure metals and existing commercial and experimental alloys in oxygen has been accomplished and is ongoing (refs. 1 to 8). Tests with pure

metals configured as wire meshes have indicated that nickel has a superior resistance to

combustion compared to the other metals (ref. 1). This led to the investigation of 17

nickel-binary alloys in which the flammability of nickel alloyed with aluminum, cobalt,

chromium, molybdenum, titanium, and manganese was determined (see table 1) (ref.

2). These elements are added to nickel to produce more favorable mechanical and

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physical properties. Of all the alloys tested, only Ni-50 Cr was found to be flammable at

an oxygen pressure of 10 000 psig. This result indicates that further investigation of

more complex nickel-base alloys may indeed produce burn-resistant alloys which are

lighter and stronger than alloys currently available.

Tests have also been conducted on relatively flammable aluminum and titanium-base

alloys that are light and strong with the objective of making them more burn resistant.

Tests on aluminum alloys have revealed that the addition of lithium, which is highly

reactive, increased the minimum pressure required to support combustion from 30 to

200 psia (ref. 3) but slightly increased the likelihood of ignition by mechanical impact

(ref. 4). Flammability tests on commercially available and experimental titanium-base

alloys are currently underway. To date, no improvement in the burn resistance of

titanium alloys has been observed.

PLANNED FUTURE WORK

The activation of the alloy formulation facility will be completed, new alloys will be

formulated, and test samples will be produced. Flammability tests on existing metals

and alloys will continue and tests on newly formulated alloys will be performed; this

will include more complex nickel-base alloys. Work to understand why lithium had a

favorable affect on the flammability of aluminum-base alloys will be investigated and

the results will be applied to new alloy development. Further testing on titanium-base

alloys will continue. Supplementary fund sources amounting to $75k have been identified for FY91.

EXPECTED COMPLETION DATE

The Center Director's Discretionary Fund objective of implementing the formulation

facility will be completed in FY91. Flammability testing and new alloy development

will continue as supported by supplementary fund sources.

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REFERENCES

1. Stoltzfus, J. M.; Lowrie, R.; and Gunaji, M. V.: Burn Propagation Behavior of Wire

Mesh Made From Several Alloys. Flammability and Sensitivity of Materials in

Oxygen Enriched Atmospheres, vol. 5, ASTM STP Iill, edited by J. Stoltzfus and

K. McIlroy, American Society for Testing and Materials, Philadelphia, 1991.

2. Kazaroff' J.i Stoltzfus, J.; Gunaji, M.: Flammability of Nickei2Binary Alloys in Oxygen. Presentation to be made at the ASTM Committee G04 Fifth International

Symposium on the Flammability and Sensitivity of Materials in Oxygen Enriched

Atmospheres, Noordwijk, The Netherlands, 1991.

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Tack, W.T.; McNamara, D. K.; Stoltzfus, J. M.; and Sircar, S.: Aluminum-Lithium

Alloys: Mechanical Property and Composition Effects on Liquid Oxygen Compatibility. Flammability and Sensitivity of Materials in Oxygen Enriched Atmospheres, vol. 5, ASTM STP 1111, edited by J. Stoltzfus and K. MclIroy, American

Society for Testing and Materials, Philadelphia, 1991.

Simon, N.J.; McColskey, J. D.; Reed, R. P.; and Gracia Salcedo, C.M.: Reaction: _

Sensitivities of A1-Li Alloys and Alloy 2219 in Mechanical-Impact Tests. Flammability and Sensitivity of Materials in Oxygen Enriched Atmospheres, vol. 5, ASTM

STP 1111, edited by J. Stoltzfus and K. McIlroy, American Society for Testingand

Materials, Philadelphia, 1991.

Schoenman, L. and Franklin, J.E.: Flame Propagation Rate of Unalloyed Beryllium

and Silicon Nitride in Oxygen. Flammability and Sensitivity of Materials in Oxygen Enriched Atmospheres, vol. 5, ASTM STP 1111, edited by J. Stoltzfus and K.

McIlroy, American Society for Testing and Materials, Philadelphia, 1991.

Sircar, S.; Stoltzfus, J. M.; and Gunaji, M. V.: The Relative Ignitability and Flamma

bility of Lead-Tin Binary Alloys. Flammability and SeFlsitivity of Materials in _ :_

Oxygen Enriched Atmospheres, vol. 5, ASTM STP 1111, edited by J. Stoltzfus and

K. McIlroy, American Society for Testing and Materials, Philadelphia, 1991.

Steinberg, T. A., and Benz, F. J.: Iron Combustion in Microgravity. Flammability

and Sensitivity of Materials in Oxygen Enriched Atmospheres, vol. 5, ASTM

STP 1ii i, edited by J. Stoltzfus and K. McIlroy, American Society for Testing and

Materials, Philadelphia, 1991.

Steinberg, T. A.; Mulholland, G. P.; Wilson, D. B.; and Benz F.J.: The Combustion of

Iron in High Pressure Oxygen. Combustion and Flame, (to be published).

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TABLE 2. RESULTS OF FLAMMABILITY TESTS

ON NICKEL-BINARY ALLOYS

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(psig) of tests

Ni-IA1 10 000 5 NB

Ni-3A1 10 000 5 NB

Ni-5AI I0 000 5 NB

Ni-5Co 10 000 5 NB

Ni-10Co 10 000 5 NB

Ni-20Co 10 000 5 NB

Ni-25Co 10 000 5 NB

Ni-2Mo 10 000 5 NB

Ni-6Mo 10 000 5 NB

Ni-10Mo 10 000 5 NB

Ni-10Cr 10 000 5 NB

Ni-20Cr 10 000 5 NB

Ni-50Cr 10 000 1 CB

Ni-50Cr 7 500 1 CB

Ni-50Cr 5 000 1 CB

Ni-50Cr 3 000 1 CB

Ni-50Cr 2 000 1 CB

Ni-50Cr 1 500 1 CB

Ni-50Cr 1 000 1 CB

Ni-50Cr 500 1 CB

Ni-50Cr 300 1 NB

Ni-50Cr 200 2 NB

Ni-lTi 10 000 5 NB

Ni-3Ti 10 000 5 NB

Ni-5Ti 10 000 5 NB

Ni-lMn 10 000 5 NB

Ni-2.3Mn !0 000 5 NB

NB The sample was ignited but no sustained burning occurred.

CB The sample burned completely.

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TITLE OF INVESTIGATION: Trace Element Analysis of Individual Cosmic

Dust Microparticles

PROJECT MANAGERS: Michael E. Zolensky/SN2/483-5!28

David J. Lindstrom/SN2/488-5012

Marilyn M. Lindstrom/SN2/483-5135

INITIATION YEAR: FY88

FUNDING: Total prior years

In-house: 130k

Contractors: 0

Grants: 0

FY90

40k

0

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Total funds: 130k 40k

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OBJECTIVE , ,: :_. , :

New techniques are being developed to determine trace element abundances in microscopic particles. Instrumental Neutron Activation Analysis techniques are being extended to smaller sample sizes by utilizing the extremely low gamma-ray background

of JSC's unique Radiation Counting Laboratory and high-efficiency gamma ray detectors to allow detection of small amounts of radioactivity induced in the samples during

intense neutron bombardment in a high-flux nuclear reactor. Samples smaller than one

nanogram (10-9 g) have been analyzed for a variety of elements, some of which are

detected at concentrations Iess than I ppm. We are initially employing this technique to

analyze single grains of cosmic dust as well as spacecraft debris and putative martian

samples.

ACCOMPLISHMENTS IN FY90

The technique development phase is essentially complete and has been described in a

paper (ref. 1) presented to the Seventh Symposium on Radiation Measurements and

Applications that is now in press. A second paper (ref. 2) describing low-level counting

facilities is also in press. Several irradiations of cosmic dust particles have been completed, and the results have been presented orally at the Lunar and Planetary Science

Conference and the abstracts published (refs. 3 and 4)_ Some related work on meteorite

samples was the subject of another abstract (ref. 5). In addition, projects utilizing these

techniques have begun on samples of possible martian weathering products in the

shergottite meteorite EETA 79001 (ref. 6), and on volcanic glass inclusions in 500-million

year old terrestrial quartz grains. This technique may also be employed to aid in the

characterization of particle residues from impact craters on surfaces of the Long Duration Exposure Facility (LDEF). All these results are b6ing written up for publication.

This year, the gamma-ray counting facilities developed for this project have been used

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extensively for analysis of radiation effects on LDEF. Nearly one hundred samples,

mostly metals, have been counted for gamma-ray activities induced by the space radiation environment. The amounts of different isotopes produced, depending on the

target materials and location on the spacecraft, will be used to construct better models

of the radiation environment to which astronauts are exposed.

PLANNED FUTURE WORK

These techniques will be used on a variety of materials, in order to solve a variety of

scientific problems. The main focus is likely to remain cosmic dust and other finegrained extraterrestrial materials because of the scientific importance of these materials

and the powerful combination of these nondestructive trace element analysis techniques with electron microscopy and other work. We are preparing manuscripts describing scientific results from the initial analyses. A proposal to the Office of Space

Science and Applications (OSSA) was funded at a start-up level in FY89, and a new

proposal to fund this work fully is to be submitted this spring.

EXPECTED COMPLETION DATE

Technique development is essentially complete, although further optimization to solve

specific problems will continue. Further work is expected to be funded by OSSA.

REFERENCES

1. Lindstrom, D.J.: Analysis of Submicrogram Samples by INAA. Nuclear Instr.

Meth. Phys. Res., in press and oral presentation, (1991).

. Lindstrom, R.M.; Lindstrom, D.J.; Slaback, L.A.; and Langland, J.K.: A Low-Back

ground Gamma Ray Assay Laboratory for Activation Analysis. Nuclear Instr.

Meth. Phys. Res., in press, (1991).

. Lindstrom, D.J.; Zolensky, M.E.; and Martinez, R.R.: INAA of Cosmic Dust Par

ticles from the Large Area Collector (abstract and oral presentation). Lunar and

Planetary Science XXI, 700-701, (1990).

. Lindstrom, D.J.; and Martinez, R.R.: Trace Element Analysis by INAA of Possible

Martian Weathering Products in Shergottite EETA 79001 (abstract). Lunar and

Planetary Science XXII, in press, (1991).

. Lindstrom, D.J.; Zolensky, M.E.; and Martinez, R.R.: Compositional Variations in

Cosmic Dust-sized Pieces of Murchison Matrix (abstract). Lunar and Planetary

Science XXI, pp. 698-699, (1990).

. Lindstrom, D.J.; Zolensky, M.E.; and Martinez, R.R.; INAA of Large Interplanetary

Dust Particles from Collector L2005 (abstract). Lunar and Planetary Science

XXII, in press, (1991).

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TITLE OF INVESTIGATION: Human Spacecraft Design

PROJECT MANAGERS: Clarence A. Bell/ER/483-4644

Ann Bufkin/ET/483-6619 .....

TEAM MEMBERS:

INITIATION YEAR: 1990

Kathy Daues, Trish Petete, Mariann Brown, Diana Villarreal, Joe

Riccio, Don Allison, Ed Robertson, Jim Masciarelli, David

Rodriquez, Scott Simmons, Nathan Moore, Robert Trevino, Scott

Wright, Don Nelson, Jeff Hein, Elaine Stephens, Tom Moore ,

George Str0_ai, Howard Ashley, James Schornick, Don Morrison,

Jeri Brown, Palmer Chiu, Ginger Pack, Mike Eubanks, Irene

Verinder, Don Donohoe, Barbara Hernandez, Jon Kahn, Mike

Langan, Jim Lee, Angie Law, Dane Russo, Jeff Davis, Karen

Mathes, and Jim Waligora

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FUNDING •

Total prior },ears

In-house : 0

C0ntractors: i _ X

Grants:

FY90

75k

Total funds: 0 75k

To develop manned spacecraft design options for the initial lunar missions (low Earth

orbit (LEO) tO lunar surface anciback toLEO)i _ .....................

ACCOMPL]SHMi_NTg _FY90 ' ......

Formed a multidirectorate design team to support the future manned spacecraft

design for lunar and Mars exploration _ ,-

• Developed and documented lunar transporl:ation system (LTS) requirements

• Designed two alternative LTSs

• Created desktop models for both LTS designs (construction begun in December)

....... ................................. =:=

• Initiated a spacecraft design data base

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Created project brochure and computer animation (both in final stages of

completion)

PLANNED FUTURE WORK

Continue lunar work and begin Mars issues, requirements, and vehicle definition

Specific interest in: radiation protection, gravity effects, health care and biological

effects, viewing requirements definition/pilot ergonomics, systems integration,

concept development, mass properties assessment, costing, etc.

EXPECTED COMPLETION DATE

The estimated completion date at this time is December 31, 1991.

REFERENCES

Final report due out in February 1992.

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TITLE OF INVESTIGATION: High Resolution Optical Rate Sensor

PROJECT MANAGER: Joseph Thibodeau/EG1/483-8232

Induiis Saulietis/EG4

TEAM MEMBERS:

Don Downing, Lockheed Engineering

INITIATION _AR: 1988 .........

FUNDING: FY88 FY89

Tony Pham/EG4

Jo Uhde-Lacovara, Ph.D., Stevens Institute, UHCL _ .......

FY90

In-house: 50k

Contractor: 0

Grants: . -0

40k

0

0

40k

0

0

Total funds: 50k 40k 40k

OBJECTIVE

Investigate the performance of image processing algorithms for implementation in a

high-resolution, optical, attitude rate sensor.

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ACCOMPLISHMENTS IN FY90

Applied digital filtering methods to the image processing of high resolution digital

signals from a megapixel charge coupled device (CCD) video camera. An algorithm to

provide attitude rate information by directly manipulating the sensor pixel intensity

output was developed and tested (refs. I and 2).

The rate algorithm works well for simulated star images. When zero mean Gaussian

noise with a standard deviation of 5 is added to the simulated data of a star image

moving at a constant rate, the algorithm derives the rate with an error of 1.9 percent at a

rate of 1.28 pixels per frame. When camera data were collected for a moving image

from a fiber optic light source (fig. 31), unexpected systematic intensity errors corrupted

the derived rate measurements.

The Kodak CCD large-scale integrated array exhibits a sixteen pixel periodicity in

measurement intensity due to the physical layout of the array. More work is required

in the camera electronics to eliminate the systematic errors, or the errors must be adequately described and modeled as part of the system software and implemented in the

rate derivation algorithm. In addition, the studies indicate a need for more dynamic

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range than that offered by the Kodak chip and the need for a cooled camera to reduce

thermally generated noise. These considerations would be part of any future study

efforts.

PAPERS

Uhde-Lacovara, J.: High Accuracy Optical Rate Sensor. NASA/ASEE Summer Faculty

Fellowship Program, August 17, 1990.

PLANNED FUTURE WORK

None.

EXPECTED COMPLETION DATE

Algorithm development task completed.

REFERENCES

. Uhde-Lacovara, J.: Analysis of the Continuous Stellar Tracking Attitude Reference

(CSTAR) Attitude Rate Processor. NASA/ASEE Summer Faculty Fellowship

Program, vol. 2 (N87-25884) pp. 19-85, 1986.

2. Uhde-Lacovara, J.: Optical Rate Sensor Algorithms. NASA/ASEE Summer Faculty

Fellowship Program, vol. 2 (N90-24985) pp. 18-80, 1989.

Star plate

Fiber Optic filters Collimator

light source __._ _ Lens Camera _----"]

_icrometer Drive _ m I

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Figure 31. Optical rate sensor experiment.

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TITLE OF INVESTIGATION: Network-Based Video Image Link

PROJECT MANAGER: Charles R. Price/ER4/483-1523

University Space Automation and Robotics Consortium

TEAM MEMBERS: Dr. Donald Johnson, Rice University

Dr. Richard Volz, Texas A&M University

Dr. Delbert Tesar, University of Texas at Austin

Dr. George Kondraske, University of Texas at Arlington

INITIATION YEAR: 1990

FUNDING: Prior years FY90

In-house 0 0

Contractors 0 0

Grants 0 50k

Total funds 0 50k

OBJECTIVE

The purpose of this project is to provide video !nterface hardware to a new robotics

network being developed to link the robotics laboratories of the Lyndon B. Johnson

Space Center (JSC), Rice University, Texas A&M, University of Texas (UT) at Austin,

and UT at Arlington. The network is being established to provide access to a pooled set

of very expensive robotics equipment, to greatly increase the efficiency of the use of this

equipment, to promote technical communications among the institutions regarding

robotics, and to provide a realistic environment for the study of transport lag and other

aspects of ground control of multiple space robots. The video interfacehardware

(frame grabbers and video compression boards) allows for the use of commonly available communications links (e.g., Internet) to transmit slow scan video images of the

robotic workspace to the operator and to the performance monitoring n0de _--:

workstations.

ACCOMPLISHMENTS IN FY90

Video interface hardware was specified and procured to link Texas A&M and Rice

University over the Susquinet network (the State version of Internet) which was also

used to link the UT at Austin and the UT at Arlington.

A graphics workstation was procured also to host the Austin kinematic robotics

graphics package developed at JSC in order to provide commonality of robotics

modelling software.

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A highly impressive demonstration of the concurrent control of three robots and

simulations at three schools with performance monitoring at a fourth was given to

JSC representatives of the New Initiatives Office, Engineering Directorate, Missions

Operations Directorate, and the Space Station Program Office on February 1, 1991.

The video interface hardware functioned to confirm that predictive simulations of

the robotics workspace presented at the operator's workstation can be successfully

used to control remote robotics to perform orbital replacement unit changeout tasks

in spite of a variable time lag in command and feedback signals of 3 to 5 seconds

between the operator and the robots.

PLANNED FUTURE WORK

A command and control node will be established in Building 9C and added to the

newwork as well as the JSC robotics laboratories. Expansion of the robotics network to

include all NASA centers and external national and international academic and industrial institutions is currently being proposed to Code R. Applications studies of the

ground control of robots for Space Station maintenance and for lunar/Mars operations

are being proposed to the appropriate project offices.

EXPECTED COMPLETION DATE

The Network-Based Video Image Link effort funded by the Director's Discretionary

Fund will be completed by June 1991. The use of the equipment will continue in the

expansion and application of the robotics network.

REFERENCES

Formal documentation is expected by June 1991.

83
TITLE OF INVESTIGATION: Lunar BasedMockups

PROJECT MANAGER: Nathan Moore/SP/483-4308

TEAM MEMBERS: Nick Pausbeck, Chip Waiters, Lindsay Gupton

INITIATIONYEAR: FY90

FUNDING:

In-house:

Contractors:

Grants:

FY90

50k (Johnson Engineering)

Total funds: 50k

OBJECTIVES" .....

The study described by this report was commissioned to develop concepts pertaining

tothedesT_n-6Tan i-n-ff_ai lunar outpost. This habitat w0uId serve-ad-a- po_nf-deSi_ _:

for use in the verification of habitat parametrics and as the source design for fullsize

mockup documentation. The three products produced by this study were (1) the

design of an initial lunar habitat topology; (2) hypermedia documentation of the

design, intended to run on Macintosh workstations; and (3) a full-size mockup of

the habitat.

ACCOMPLISHMENTS IN FY90

This study provided one of many data points required for parametric analysis of habitats in Lunar and Mars mission initiatives. This reference design along with detailed

subsystem information serves as a habitation systems database for use by program

offices, mission planners, and line organizations in sizing habitats for mission architectures. The study also provides presentation mediums (full-size mockups and

hypermedia) that allow understanding of the habitat by all viewers.

The study also identified new levels of technology which must be attained before missions can be successfully conducted. Examples of this are partial-gravity, human habitability, and performance parameters. Knowledge gained in these new technologies will

be used in further iterations of design studies such as this one.

This design study, due to its indepth look at lunar base habitability, has been very

effective in documenting current habitat configurations and in identifying areas of

further study needed to fill knowledge gaps in habitability research. The hypermedia

presentation produced by this study has received wide attention by most agencies

currently performing lunar base habitation studies. The mockup, recently completed,

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provides the opportunity to experience the design in full scale. The initial lunar outpost

construction module (figs. 32-35) is designed around the Space Station Freedom module

pressure hull and is 4.2 by 12m in length. The interior is substantially different, both in

principal and execution, in order to better accommodate the scope of its mission and the

partial-gravity environment present on the lunar surface. The exterior contains structure both for module support/leveling, and for radiation shielding support. The radiation shielding material used is lunar soil.

The module is intended to accommodate up to six crewmembers for periods of 30 to 60

days. This single unit must provide for all aspects of living and working during this

extended period, and the module is therefore subdivided into five distinct "activity

zones": sleep station/crew quarters; wardroom/galley/exercise (living area); hygiene/

waste management; stowage; and operations/workstations. These zones are intended

to be distinct from each other both operationally and architecturally to give a sense of

purpose to each as well as provide variety.

PLANNED FUTURE WORK

Planned events for FY91 include work on the mockup to improve the fidelity after

elements of the design are revisited. A detailed report on this design is in the process of

being written for submission to NASA for publication as a technical paper. Expected

completion schedule depends on resources allocated to this project.

REFERENCES

1. Initial Lunar Habitat Design Control Specification. Prepared by Design Edge Inc.

(for Johnson Engineering Corp.), June 19,1990.

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Figure 32. Interior view of telerobotic workstations.

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Figure 33. Exterior view showing airlock, radiation protection, and radiators.

O,_IG_,NAL PAGE IS

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Figure 34. Interior view of topology.

O_GINAL PAG£ IS

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Figure 35. Interior view of wardroom galley area.

ORIGINAL PAGE iS

OF POOR qtJ,lU.iTY

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REPORT DOCUMENTATION PAGE

NationalAeronauticsand

SpaceAdministration

1. ReportNo. 2. GovernmentAccessionNo.

NASA TM 102177

4. TitleandSubtitle

JSC Director's Discretionary Fund Program

7. Author(s)

New Initiatives Office

9. PerformingOrganizationNameandA_re_

New Initiatives Office

NASA Lyndon B. Johnson Space Center

Houston, Texas 77058

12.SponsoringAgencyNameandAddress

3. Recipient'sCatalogNo.

5. ReportDate

April 1991

6.PerformingOrganizationCode

IA

8.PerformingOrganizationReportNo.

10.WorkUnitNo.

11.ContractorGrantNo.

13.Typeof ReportandPeriodCovered

Technical Memorandum

National Aeronautics and Space Administration

Washington, D.C. 20546 14.SponsoringAgencyCode

15.SupplementaryNotes

16.Abstract

The JSC Director's Discretionary Fund Program Annual Report provides a brief

status of the projects undertaken during the 1990 fiscal year. For this

year, three space exploration initiative related issues were focused on:

regenerative life support, human spacecraft design, and lunar surface

habitat. In this way, a viable program of life sciences, space sciences,

and engineering research has been maintained. For additional information

on any single project, the individual investigator should be contacted.

17.KeyWords(SuggestedbyAuthor(s))

Space Exploration Initiative, regenerative life support, human spacecraft

design, lunar surface habitat, artificial intelligence

18.DistributionStatement

Unclassified - Unlimited

Subject Category: 91

19.SecurityClassification(of thisreport) 20.SecurityClassification(ofthis page) 21. No.of Pages

Unclassi lied Unclassified 97

Forsale bytheNationalTechnicalInformationService,Springfield.VA22161-2171

JSCForm1424(RevAu¢l891(SWSFORMSDec69)

22. Price

NAS,*-JS(,
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