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Design Principles for the Development of Space Technology Maturation Laboratories Aboard the International Space Station. Thesis Defense Alvar Saenz-Otero May 4, 2005. Committee Members. Prof. David W. MillerChair MIT Space Systems Laboratory Prof. Jonathan P. HowMember - PowerPoint PPT Presentation
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Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Design Principles for the Development of Space Technology Maturation Laboratories Aboard the International Space Station
Thesis Defense
Alvar Saenz-Otero
May 4, 2005
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Committee Members
• Prof. David W. Miller Chair– MIT Space Systems Laboratory
• Prof. Jonathan P. How Member– MIT Space Systems Laboratory
• Prof. Eric Feron Member– MIT Laboratory for Information & Decision Systems
• Javier de Luis, PhD Member– Payload Systems Inc.
• Prof. Brian Williams Member/Minor Advisor– MIT Space Systems Laboratory / Minor Advisor
• Prof. Jeffrey A. Hoffman Reader– MIT Man Vehicle Laboratory
• Prof. Dava Newman Reader– MIT Man Vehicle Laboratory/Technology Policy Program
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Motivation
• Extract the design methodologies behind two decades of research at the MIT SSL in the design of facilities for dynamics and control experiments– What are the common design elements?
– Which elements eased the technology maturation process?
– Can these apply to future experiments?
– Is there a facility for microgravity research equivalent to wind-tunnels for aeronautics research?
• National Research Council calls for the institutional management of science aboard the ISS in 1999– Promote the infusion of new technology for ISS research
– Provide scientific and technical support to enhance research activities
– Selected science use on the basis of their scientific and technical merit by peer review
Problem Statement
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Approach / Outline
Create a design methodology for the development of micro-gravity laboratories for the research and maturation of space technologies
– Review of g and remote research facilities
The conjunction of– The International Space Station– The MIT SSL Laboratory Design Philosophy
present a perfect low-cost environment for the development and operation of facilities for space technology research
Build and operate SPHERES using the MIT SSL Laboratory Design Philosophy for operations aboard the ISS
– Description– Iterative Research– Support Multiple Scientists
Design Principles that guide the design of a research facility for space technology maturation utilizing the ISS
The application of the principles to review SPHERES indicates the Design Principles and frameworks present a valid methodology for the development of research facilities for maturating space technologies aboard the ISS
Problem Statement
Chapter
Conclusions
&
Contributions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions/
Contributions
1
2
3
4
5
6
7
SSL Design Philosophy
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Outline
Chapter
Conclusions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions
1
2
3
4
5
6
7
SSL Design Philosophy
• Motivation / Approach -g and Remote Research Facilities• The International Space Station• MIT SSL Laboratory Design Philosophy
• SPHERES: from testbed to laboratory– Description
– Iterative Research Process
– Supporting Multiple Scientists
• Design Principles
• Application of Principles• Contributions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
• Space based– Shuttle Middeck
– Shuttle Payload
– ISS
– Free Flyer
3(5) ~ h w $$
6 s w ~ $$$
6 h w ~ $$$
6 ~ s w ~ $$$
-g Research Facilities
• In-house– Simulation
– Air table
– Robot Cars
– Helium Balloons
– 6 DOF Robot Arms
– Robot Helicopters
Literature Research
• 3rd Party Ground based– Flat Floor
– Drop Towers
– Neutral Buoyancy Tank
– RGA (KC-135)
gDur.
MisDur.DOF Dyn. Exp. Ops. Data Acc. Cost
6 s-y mo-y $
3(5) ~ m-h mo-y $
3(5) h mo-y $
4(6) h mo-y $$
6 h mo-y $$$
4(6) h mo-y ~ $$
6 ~ h-w w ~ $$$$
6 h-w w ~ $$$$
6 h-y mo-y ~ $$$$
6 mo-y mo-y $$$$$
ISS
- N
AS
AJS
FC
RG
O K
C-1
35 -
NA
SA
MIT SSL/ACL
Environment Operations
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Remote Research Facilities
• Antarctic Research– Scientific research is primary directive
[NRC], [Elzinga, ‘93], [Burton, ‘04]
– International system [SCAR]
– Development of shared facilities in a harsh environment [Ashley, ’04]
• Ocean Exploration Research– Multiple types of research vessels
[Penzias, ’73]
– Concentrate on conducting an experiment, not data analysis [Cunningham, ’70]
– Similarities with space challenges
Literature Research
• Past Space Stations Crew
Duration
– Salyut 2-6~1y (2x)
• International cooperation, EVA’s
– Skylab [Belew, ’77] 3<1y
• Science driven: solar exp., physiology
– Space Lab [Emond, ’00] 7~2w
• International coop. aboard shuttle
– Mir [NASA], [Burrough, ‘98] 3~15y
• Tech. research, Earth & space sciences, biology, life support, shuttle docking, ISS Phase I
Space stations do provide a unique environment for microgravity researchAllow the researcher to be in-location with
facilities to conduct specific experiments
WH
OI
BA
S Skylab - [Belew] MIR - NASA
How do you design and build experiments to operate remotely under a microgravity environment?
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Outline
Chapter
Conclusions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions
1
2
3
4
5
6
7
SSL Design Philosophy
• Motivation / Approach -g and Remote Research Facilities• The International Space Station• MIT SSL Laboratory Design Philosophy
• SPHERES: from testbed to laboratory– Description
– Iterative Research Process
– Supporting Multiple Scientists
• Design Principles
• Application of Principles• Contributions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES The International Space Station
• Experiment Operation Types– Observation– Exposure– Iterative Experiments
Hypothesis
The purpose of the ISS is to provide an “Earth orbiting facility that houses experiment payloads, distributes resource utilities, and supports permanent human habitation for conducting research and science experiments in a microgravity environment.” [ISSA IDR no. 1, Reference Guide, March 29, 1995]
• Major areas of study– Educational– Pure Science– Technology
• Special Resources of the ISS– Crew
• Provide oversight of experiments, reducing the risk of using new technologies
– Communications• Reduce the costs and improve the availability of data for researchers on the ground
– Long-term experimentation• Enables taking many individual steps to slowly mature a technology
– Power• Reduces the launch requirements (mass and cost) for missions to provide basic utilities
– Atmosphere / Benign environment• Reduces cost and complexity of developing test facilities (e.g., thermal, radiation protection)
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES MIT SSL LaboratoryDesign Philosophy (1)
• Lessons learned from past experiments– MODE - Middeck 0-g Dynamics Experiment
• STS-48 (‘91): fluid slush and jointed truss structures• STS-62 (‘94): truss structures, pre-DLS
– DLS - Dynamics Load Sensor• MIR: crew motion sensors
– MACE - Middeck Active Controls Experiment• STS-67 (‘95): robust, MCS algorithms for space
structures• ISS Expedition 1 (‘00): neural networks, non-linear &
adaptive control
Hypothesis
MO
DE
DLS
MA
CE
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES MIT SSL LaboratoryDesign Philosophy (1)
• Lessons learned from past experiments– MODE - Middeck 0-g Dynamics Experiment
• Modular, generic equipment,hardware reconfiguration
– DLS - Dynamics Load Sensor• Extended investigations
– MACE - Middeck Active Controls Experiment• Multiple investigators, human observability,
iterative research, risk tolerant environment, SW reconfiguration
Hypothesis
MO
DE
DLS
MA
CE
Spe
cifi
c ve
rsus
ge
neri
c
Har
dwar
e re
conf
igur
atio
n
Ext
ende
d in
vest
igat
ions
Ris
k to
lera
nt
envi
ronm
ent
Sof
twar
e re
conf
igur
atio
n
Hum
an
obse
rve/
man
ip
Iter
ativ
e re
sear
ch
proc
ess
Mul
tipl
e in
vest
igat
ors
MODE MODE-Reflight DLS MACE MACE-Reflight
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES MIT SSL LaboratoryDesign Philosophy (2)
• The identification of these features led to the development of MIT SSL Laboratory Design Philosophy
– Based on the need to demonstrate control and dynamics algorithms, these features guide the design of a laboratory such that the results provided in the laboratory validate the algorithms themselves, and not the capabilities of the facility
Hypothesis
Group FeatureFacilitating Iterative Research Process Facilitating Iterative Research ProcessExperiment Support Data Feedback Precision
Repeatability and ReliabilityHuman Observability and ManipulationSupporting Extended InvestigationsRisk Tolerant Environment
Supporting Multiple Investigators Supporting Multiple InvestigatorsReconfiguration and modularity Generic versus Specific Equipment
Physical End-to-End SimulationHardware ReconfigurationSoftware Reconfiguration
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Outline
Chapter
Conclusions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions
1
2
3
4
5
6
7
SSL Design Philosophy
• Motivation / Approach -g and Remote Research Facilities• The International Space Station• MIT SSL Laboratory Design Philosophy
• SPHERES: from testbed to laboratory– Description
– Iterative Research Process
– Supporting Multiple Scientists
• Design Principles
• Application of Principles• Contributions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES Design
• SPHERES is...– A testbed for formation flight
• Allow reconfigurable control algorithms• Perform array capture, maintenance and retargeting
maneuvers• Enable testing of autonomy tasks• Ensure traceability to flight systems• Design for operation in the KC-135, shuttle mid-deck, and ISS
– Design guided by the SSL Laboratory Design Philosophy
• Sub-systems designed to accommodate specific features
Lab FFAvionics Software Communications Interface/Operations Propulsion Structures
Experimentation
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES Overview
• SPHERES is...– A testbed for formation flight
• SPHERES free-flier units– Up to 5 independent units with propulsion, power,
communications, metrology, and data processing– Sensors and actuators provide full state vector (6DOF)
• Laptop unit– Standard PC laptop serves as a base station
• Metrology– Five external metrology transmitters create frame of reference
• Communications– Satellite-to-satellite (STS)– Satellite-to-laptop (STL)
Upload program
Download data Thrusters
UltrasoundSensors
PressureRegulator
Battery
PressureGauge
Control Panel
Experimentation
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
• Support Multiple Scientists– Guest Scientist Program
• Information Exchange• SPHERES Core Software• GSP Simulation• Standard Science Libraries
– Expansion port
– Portability
– Schedule flexibility
• Reconfiguration and Modularity– Generic satellite bus
– Science specific equipment: on-board beacon and docking face
– Generic Operating System
– Physical Simulation of Space Environment• Operation with three units• Operation in 6DOF• Two communications channels
– Software interface to sensors and actuators
– Hardware expansion capabilities
– FLASH memory and bootloader
• Facilitate Iterative Research– Multi-layered operations plan
– Continuous visual feedback
– Families of tests
– Easy repetition of tests
– Direct link to ISS data transfer system
– De-coupling of SW from NASA safety
• Support of Experiments– Data Collection and Validation Features
• Layered metrology system• Flexible communications: real-time & post-
test download• Full data storage• 32 bit floating point DSP• No precision truth measure
– Redundant communications channels
– Test management & synchronization
– Location specific GUI’s
– Re-supply of consumables
– Operations with three satellites
– Software cannot cause a critical failure
SPHERES Features to Meet theMIT SSL Laboratory Design Philosophy
Experimentation
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
"Research is the methodical procedure for satisfying human curiosity. It is more than merely reading the results of others' work; it is more than just observing one's surroundings. The element of research that imparts its descriptive power is the analysis and recombination, the "taking apart" and "putting together in a new way," of the information gained from one's observations." [Beach]
Four major steps which support the iterative process:1) Test execution (science time: allow enough time)2) Data collection and delivery to researcher (overhead time: minimize)3) Data evaluation and algorithm modification (science time: allow enough time)4) Modification to tests and new program upload (overhead time: minimize)
[Gauch]
HypothesisHi
Design Experiment True State of Nature
New DataPrevious Data
Deduction Model of Hi
Induction New Hypothesis
Hi+1
Noise
+
Problem Statement
Initial Modeling
Hardware Test
Data evaluation
Technology Maturation
Implementation & Test Setup
4
2
Initial Implementation
TheoreticalModel
Data Collection
3
The initial modeling and implementation is not part of the
iterative research process
1Initial Setup
Science Time
Overhead Time
AlgorithmModifications
SPHERES: Iterative Research Process
• Scientific Method Steps– Design
– Deduction
– Experimentation
– Induction
– New Hypothesis
New
Hyp
oth
esis
Ded
uct
ion
Induction
ExperimentDesign
Experimentation
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsSteps 1, 2, 4
Hardware Test
Data evaluation
Technology Maturation
Implementation & Test Setup
4
TheoreticalModel
Data Collection
3
1
AlgorithmModification
2
Experimentation
• Continuous visual feedback • Families of tests• Easy repetition of tests• Location specific GUI’s• Re-supply of consumables• FLASH memory and bootloader
Optionalreal-timedata display
Debugreal-timedata One-key commands
Satellite status summary
Program and testnumbers, timing
Initialization
Data recording status
Communications status
Single key test start/stop
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Hardware Test
Data evaluation
Technology Maturation
Implementation & Test Setup
4
TheoreticalModel
Data Collection
3
1
AlgorithmModification
2
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan
Experimentation
Analyze dataSPHERES provides Matlab functions
Collect data files
Update algorithms with CCSC or C++
Compile new program image
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Data evaluation
Technology Maturation
TheoreticalModel
3AlgorithmModification
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan– Simulation: science time determined by researcher
Experimentation
All these tests are performed at the researcher home facility using their own computers.
Initial Algorithm DevelopmentResearcher
Simulation TestResearcher
Data AnalysisResearcher
Deployment to Hardware Tests
Implementation & SetupHours
1Data Collection
Minutes
2 3
4debug
Hardware Test
Implementation & Test Setup
4
Data Collection
1
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Data evaluation
Technology Maturation
TheoreticalModel
3AlgorithmModification
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan– Simulation: science time determined by researcher– SSL Off-site Tests: science time determined by researcher and SSL availability
(days/weeks/months)
Experimentation
Performed at the MIT SSL facilitiesPerformed at the researcher’s home facility.
Initial Algorithm DevelopmentResearcher
Algorithm TranslationDays
Hardware Test20 minutes
Data CollectionHours
Maturation
Algorithm Modification
Hours
24
Data AnalysisResearcher
Integration to flight code
4 1
debug
Verification Deployment to ISS 4
Simulation TestResearcher
1
Data CollectionMinutes
2 3
Hardware Test
Implementation & Test Setup
4
Data Collection
1
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Data evaluation
Technology Maturation
TheoreticalModel
3AlgorithmModification
Experimentation
Performed at the MIT SSL facilitiesPerformed at the researcher’s home facility
Initial Algorithm DevelopmentResearcher
Algorithm TranslationDays
Hardware Test20 minutes
Data CollectionMinutes
Maturation/ deployment to
ISS
Algorithm Modification
Minutes
1 2
4Data AnalysisTravel Time
3debug
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan– Simulation: science time determined by researcher– SSL Off-site: science time determined by researcher and SSL
availability (days/weeks/months)– SSL On-site: science time determined by availability / residence at
SSL facilities (days/weeks/months)
Hardware Test
Implementation & Test Setup
4
Data Collection
1
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Data evaluation
Technology Maturation
TheoreticalModel
3AlgorithmModification
Experimentation
Researcher’s home facility / MIT SSL
Maximum 4 days total operations
Researcher Remote Location (e.g. hotel)KC-135Researcher’s home facility / MIT SSL
Initial Algorithm DevelopmentResearcher
Hardware Test20 seconds
Data CollectionHours Maturation or
deployment to ISS
Algorithm ModificationMinutes
1 2
4
Data Analysis24-72 Hours
3
Visual Analysis60 seconds
3
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan– Simulation: science time determined by researcher– SSL Off-site: science time determined by researcher and SSL
availability (days/weeks/months)– SSL On-site: science time determined by availability / residence at SSL
facilities (days/weeks/months)– KC-135 RGA: science time determined by parabola time (~60s),
and length of stay at remote location (1-3 days)
Hardware Test
Implementation & Test Setup
4
Data Collection
1
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsStep 3
Data evaluation
Technology Maturation
TheoreticalModel
3AlgorithmModification
Experimentation
Limited to length of travel to MSFC
Researcher Remote Location(e.g. hotel)
MSFC Flat Floor
Researcher’s home facility / MIT SSL
Initial Algorithm DevelopmentResearcher
Hardware Test10 minutes
Data CollectionHoursMaturation or
deployment to ISS
Algorithm ModificationMinutes
1
24Data Analysis
Days
3
Visual Analysisminutes
3
Data CollectionMinutes
2Data Analysis
Few Hours
3Algorithm Modification
Minutes
4
• Guest Scientist Program– Standard Science Libraries
• Multi-layered, multi-environment operations plan– Simulation: science time determined by researcher– SSL Off-site: science time determined by researcher and SSL
availability (days/weeks/months)– SSL On-site: science time determined by availability / residence at SSL
facilities (days/weeks/months)– KC-135 RGA: science time determined by parabola time (~60s), and
length of stay at remote location (1-3 days)– MSFC: science time determined by test operations (minutes), work
day (hours) and length of stay at remote location (days)
Hardware Test
Implementation & Test Setup
4
Data Collection
1
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
ISSISS Laptop
Minutes
4
Program LoadMinutes
4
Maximum total time:2 Hours
6DOF Test30 minutes
1Astronaut feedback
MinutesData in Laptop
1
2
Preview analysisMinutes
1
VideoISS ServerMinutes
2
PSI STP JSC
Total overhead:~2 days
To JSC 1 Day
4
ISS Server1 Day
4
Performed at the researcher’s home facility.
Initial Algorithm DevelopmentResearcher
Maturation
Algorithm ModificationGND: Hours
ISS: 2 weeks cycle
4
Data Analysis2 week cycle
3Data Collection
Minutes
2
Total overhead:Hours or2 weeks cycle
Simulation TestResearcher
1
SPHERES: IterationsISS Steps
MIT SSL
Hardware Test20 minutes
Data CollectionHours
2
Integration to flight codeDays
4 1
debug
Verification Days
4Total overhead:Days
JSC STP PSI
Data Download2-3 days
Video Delivery~1 week
2
Experimentation
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: IterationsISS Steps 1, 2, 4
• Direct link to ISS data transfer system
• De-coupling of SW from NASA safety
• Physical Simulation of Space Environment– Operation with three units– Operation in 6DOF– Two communications channels
ISSISS Laptop
Minutes
4
Program LoadMinutes
4
Maximum total time:2 Hours
6DOF Test30 minutes
1Astronaut feedback
MinutesData in Laptop
1
2
Preview analysisMinutes
1
VideoISS ServerMinutes
2
Crew
ISS Laptop
SPHERES (3)
Beacons (5)
Courtesy Boeing CoStart ISS GUI
Experimentation
Hardware Test
Data evaluation
Technology Maturation
Implementation & Test Setup
4
TheoreticalModel
Data Collection
3
1
AlgorithmModification
s
2
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: More Iterative Research Features
• Software (Appendix C)– Generic Operating System– Software cannot cause a critical failure– Test management & synchronization
Test Time 2 [ms]
n/a n/a n/a n/a -1000 -800 -600 -400 -200 0 200
UserInput
LaptopControl
Sat 1
Sat 2
15ms
Bad
RX
sync
7865 8065 8265 8465 8665 8865 9065 9265 9465 9665 9865Sat 2 Time
Sat 1 Time
Laptop Time[s]
sync
Test Time 1 [ms]
star
t
Data TXData RX“Start Test” PacketTX Window
n/a -1000 -800 -600 -1000 -800 -600 -400 -200 0 200
4321 4521 4721 4921 5121 5321 5521 5721 5921 6121 6321
572.1 572.3 572.5 572.7 572.9 573.1 573.3 573.5 573.7 573.9 574.1
HW DSP/BIOS SPHERES Core GSP
Comm
IMU
Global Met.
SW Interrupts
StandardScienceLibraries
Tasks
HW Interrupts
Controller
Propulsion
Housekeeping
Comm
IMU
Global Met
Propulsion
GSP BackgroundTask
Control
Met. (IMU)
BackgroundTask
TestInit
Controllers
Estimators
Maneuvers
Mixers
Met. (Global)
GSP MetrologyTask
MetrologyTask
SPHERESMet. Task
Hidden Interfaces User-accessible Interface
Terminators
Math
Utilities
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: More Iterative Research Features
• Avionics (Appendix B)– Layered metrology system– 32 bit floating point DSP
• Communications (Appendix D)– Flexible communications: real-time &
post-test download – Full data storage
DSP Memory BusesSerial LinesDigital I/O signalsAnalog signals
Micro Processor(C6701 DSP)
Metrology AvionicsFPGA
CommunicationsAvionics
(PIC MCU’s)
A2D
US/IR12x
STLRF
STSRF
Watchdog
ControlPanel
Power Propulsion
Solenoids
Amplifiers
Accelerometers
Gyroscopes
ExpansionPort
BatteryPacks
Beacon
HW
I COMM Rx
CLK (BIOS)
CL
K
Comm TDMA Mgr
SW
I
COMM Tx
PRD (BIOS)
Fast Housekeeping
TelemetryT
SK
COMM Mgr
DataComm STL DataComm STS
CP Monitor
Pri
ori
ty
receive data, put into RX pipes
enable transmission SWI
send packets to DR2000 when enabled
manage state of health packets
manage background telemetry packets
prepare TX packets; process RX packets
process large data transmissions
initialize commports
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: Supporting Multiple Scientists
• Families of tests Software, Operations
• Guest Scientist Program– Information Exchange Operations– SPHERES Core Software Software– GSP Simulation Operations
• Expansion port Avionics, Software
• Portability System
• Schedule flexibility Operations
Research Year Application Guest ScientistFF Communications 2000-03 DSS GoddardFF Control 2000+ TPF JPLDocking Control 2002+ Orbital Express (DARPA)Mass ID / FDIR 2003+ Modeling AmesTethers 2003+ SPECS GoddardMOSR 2004+ Mars Sample Return
Current Programs
dx
xf
yf
xl
yl
Follower
Leader
f
dy
l 0dx
xf
yf
xl
yl
Follower
Leader
f
dy
l 0
Mass IDARD
Future Programs
Tethers MOSRMulti-stage TPFTPF
Experimentation
NA
SA
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Group Av
ion
ics
Co
mm
.
Op
era
tio
ns
So
ftw
are
Facilitating IterativeResearch Process
Experiment Support
Supporting MultipleInvestigators
Reconfiguration andmodularity
SPHERES: A Laboratory
• SPHERES is...– A testbed for satellite formation flight
– The SPHERES implementation satisfies all four groups of the philosophy
• Laboratory: a place providing opportunity for experimentation, observation, or practice in a field of study
– Therefore, by following the SSL Laboratory Design Philosophy, SPHERES is…
• A separated spacecraft laboratory!– It is a reconfigurable and modular laboratory which supports conducting
-g iterative experiments by multiple investigators
LABORATORYLABORATORY
Experimentation
Terrestrial Planet FinderMOSR SPECS Orbital Express
NA
SA
NA
SA
DA
RP
A
NASA
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Outline
Chapter
Conclusions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions
1
2
3
4
5
6
7
SSL Design Philosophy
• Motivation / Approach -g and Remote Research Facilities• The International Space Station• MIT SSL Laboratory Design Philosophy
• SPHERES: from testbed to laboratory– Description
– Iterative Research Process
– Supporting Multiple Scientists
• Design Principles
• Application of Principles• Contributions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Results
Design Principles for -gLaboratories Aboard the ISS
• These principles were derived from the implementation of the MIT SSL Laboratory Design Philosophy in SPHERES for operations specifically aboard the ISS– The principles encompass all features of the philosophy following the four
main groups presented above
– The principles incorporate the special resources of the ISS
• The following seven principles capture the underlying and long enduring fundamentals that are always (or almost always) valid [Crawley] for space technology maturation laboratories:– Principle of Iterative Research
– Principle of Enabling a Field of Study
– Principle of Optimized Utilization
– Principle of Focused Modularity
– Principle of Remote Operation & Usability
– Principle of Incremental Technology Maturation
– Principle of Requirements Balance
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Studies the “depth” of the research
Results
Concept
Hypothesis
TechnologyMaturation
Conception
Science Time
Overhead Time
ExperimentImplement
ExperimentOperation
Data Collection
DataAnalysis
ExperimentDesign
Facility Design
Principle of Iterative Research
• A laboratory allows investigators to conduct multiple cycles of the iterative research process in a timely fashion
• Three iteration loops:3
– Modify the hypothesis about the goals and performance requirements for the technology.
New Hypothesis
Ded
uct
ion
Induction
– Modify the experiment design to allow for comparison of different designs.
2
Des
ign
1
Exp
erim
ent
– Repeat the test to obtain further data.
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Iterative Research
• Composed of three elements:– Data collection and analysis tools
• Collection bandwidth, precision, accuracy• Transfer rate, availability
– Enable reconfiguration• To allow the three feedback loops to be closed
– Flexible operations plan• Flexible time between
iterations– Too little time prevents
substantial data analysis
– Too much time createsproblems with resourcesand institutional memory
• Maximize number ofiterations possible
Results
good
bad
good bad
MACE
MACE-II
DLS
EffectiveIterativeResearch
IneffectiveIterativeResearch
ShuttleISS
MIR
RG
A
Time between iterations i
Num
ber
of
itera
tions
MODE-Reflight
0n>
>1
small large
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Results
Principle of Enabling a Field of Study
• A laboratory provides the facilities to study a substantial number of the research areas which comprise a field of study– Every facility must be part of a clearly defined field of study
• The objective of a facility must clearly indicate what field of study it will cover
– The study of multiple topics requires multiple experiments to be performed• Individual scientists perform research on one or a few areas• The work on individual topics collectively covers the field of study• Therefore multiple investigators, who perform experiments in their specific area of
expertise within the field, must be supported
– The laboratory must facilitate bringing together the knowledge from the specific areas to mature understanding of the field of study
• Enable collaborative research
Covers the “breath” of the research, how much of a field of study can be covered by the facility
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Enabling a Field of Study
• The methods to evaluate the efficiency of a laboratory can be compared to the methods used to determine the efficiency of product platforms– Product platform evaluations compare the cost of developing a new product
with respect to the original product [Meyer]
– Laboratories compare the cost of testing specific areas (ki) in its facilities (with initial cost Klab) compared to creating original facilities for each area (Ki)
– Laboratories promote covering multiple areas (m/n)
n
ii
n
iilab
K
kK
n
mJ
1
1
Results% of field of study covered
Increased costper area of study
0% 25% 50% 75% 100%Fra
ctio
nal c
ost
of
Labo
rato
ry
1
Expensive area
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Remote Operation & Usability
• A remotely operated laboratory, such as one which operates aboard the ISS, must consider the fact that remote operators perform the everyday experiments while research scientists, who do not have direct access to the hardware, are examining data and creating hypotheses and experiments for use with the facility
• Remote facilities are remote because they offer a limited resource that the researcher cannot obtain in their location
• Therefore the operations and interface of a remote facility must– Enable effective communications between operator and research scientist
– Enable prediction of results
– Ultimately: create a virtual presence of the scientist through the operator
• Research Scientists– have little or no experience on the
operational environment
– are unable to modify the experiment in real-time
– are usually an expert in the field but not in implementation
– may not have direct contact with the facility
• Operators– are usually not an expert in the specific field
– are an inherent part of the ‘feedback’ loop to provide researchers with results and information
– are a limited resource
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
FunctionalRequirements
EngineeringRequirements
ManagementRequirements
ScienceRequirements
MissionObjective
Enabling a Field of Study
Iterative Research
Optimized Utilization
Focused Modularity Req’s Balance
Remote Operation
Technology Maturation
FacilityDesign
Results
Design Framework
• How to use the principles in a laboratory design– Step 1 - Identify a Field of Study
• Select a large enough area in the field of study that the experiment can support technology maturation, but not so large that it is impossible to identify a clear set of science requirements
– Step 2 - Identify Main Functional Requirements• Identify data, reliability, and schedule requirements to enhance the iterative research process• Define representative environment and utilization of the ISS
– Step 3 - Refine Design• Identify opportunities for modularity to help both the project and the ISS program• Determine requirements for remote operations
– Step 4 - Review Requirements and Design• Balance requirements
1 2 3 4
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Outline
Chapter
Conclusions
Results
Experimentation
Hypothesis
ObjectiveMotivation
& Other Facilities
ISS & Facility Characteristic
SPHERES
Design Principles & Frameworks
Evaluations
Conclusions
1
2
3
4
5
6
7
SSL Design Philosophy
• Motivation / Approach -g and Remote Research Facilities• The International Space Station• MIT SSL Laboratory Design Philosophy
• SPHERES: from testbed to laboratory– Description
– Iterative Research Process
– Supporting Multiple Scientists
• Design Principles
• Application of Principles• Contributions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principles Applied to SPHERES
• Success– Enables iterative research (demonstrated)
• Fulfills the three parts of the Principle of Iterative Research: successful data management, flexible operations plan, and enable multiple levels of repetitions and iterations
– Supports multiple scientists (demonstrated)• The GSP has enabled at least six groups to participate in SPHERES
– Utilizes most ISS resources correctly (designed, expected)• Designed to utilize the crew, telemetry, long-term experimentation, and benign environment features
– Balances generic and specific equipment (demonstrated)• The satellite bus implemented by the SPHERES units provides generic equipment• The expansion port allows integration of science specific equipment
– Creates a remote laboratory environment (demonstrated in ground, expected in ISS)• The portability and custom interfaces create a remote laboratory outside of the main SSL facilities
– Allows incremental technology maturation up to TRL 6 (expected)• Creates the necessary representative environment to satisfy the definition of TRL 5 and TRL 6
• Recommendations– Design/Eval: Improve use of ISS power sources
• While power consumption is minimal (~50W), none comes from the ISS resource
– Design: Imbalance in resources allocated to metrology sub-system development vs. power/expansion
• Allocation of resources (esp. man power) to metrology prevented improved design of power/expansion
– Eval: Minimal modularity from ISS perspective• While modular from DSS perspective, provides no generic equipment for ISS use
Conclusions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Contributions: Principles
• Identified the fundamental characteristics of a laboratory for space technology maturation
– Formalized the need for a laboratory to support iterative research• Based on the definition of the scientific method
• Called for reduced dependency on DOE
– Identified the need to enable research on a field of study• Requires support of multiple scientists in most cases
– Advocate the use of the ISS as a wind-tunnel-like environment for g research
• Established a set of principles to guide the design of research laboratories for space technology maturation aboard the International Space Station
– Enables the use of the ISS to incrementally mature space technologies– Developed a design framework– Developed an evaluation framework to respond in part to the NRC institutionalization of
science aboard the ISS• Calls for a change in attitude towards the use of resources aboard the ISS: don’t treat as costs
to minimize; treat as added value, so maximize their correct use
Conclusions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Contributions: SPHERES
• Designed, implemented, and operated the SPHERES Laboratory for Distributed Satellite Systems
– Multiple researchers can advance metrology, control, and autonomy algorithms• Up to TRL 5 or TRL 6 maturation
– Demonstrates the implementation of miniature embedded systems to support research by multiple scientists
• Developed a real-time operating system with modular and simple interfaces
– Demonstrates the ability to create generic equipment– Enables future expansion through both hardware and software– Approaches virtual presence of the scientists in a remote location
• Present the operator with the necessary initial knowledge and feedback tools to be an integral part of the research process
Conclusions
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
Questions?
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Optimized Utilization
• A well-designed laboratory considers all the resources available and optimizes their use with respect to the research needs
• Understand the resources and limitations of the ISS– Crew
– Power sources
– Data telemetry
– Long-term experimentation
– Benign Environment / Atmosphere
• Determine the needs of the research– Allow flexibility in the needs of the laboratory; maximize the ability to use available
resources
• Realize which resources do not provide a benefit to the research
• Iterate this process to ensure all available resources are utilized as best as possible
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Optimized Utilization
• Using the resources of the ISS provides a value to the laboratory– Based on the Taguchi values
– Using a resource should not be a “cost” to minimize
• Utilize crew ~12hper month
• Minimize power req.
• Maximize % of powerfrom ISS
• 100kbps-400kbpsbandwidth is best
• Lifetime ~1-5y
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Focused Modularity
• A modular facility identifies those aspects of specific experiments that are generic in nature and allows the use of these generic components to facilitate as yet unforeseen experiments. Such a facility is not designed to support an unlimited range of research, but is designed to meet the needs of a specific research area.
• During development of a facility identify the generic components but ensure that the initial research goals are met
– The original immediate research should not be compromised– The experiment generic components can become part of a larger array of generic
elements that brought together create a laboratory environment
• Do not try to design a “do-everything” system– The generic equipment should be identified after the design of the original
experiment; the original design should not be to create generic equipment
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Focused Modularity
• Metric / Evaluation– Evaluate each major component (sub-system) of the testbed using the
following truth table:
– Determine the cost difference between making a sub-system modular or not
Inte
r-di
scip
line
Rec
onfi
gure
Obs
olet
e
Lif
e-li
mit
ed
Cos
t A
mor
tize
Ori
gina
l G
oals
Make Modular x x x x x 0 0 x x 0 x x x 0 x x x 0 x x 0 0 0 1 1 0 1 0 1 x 1 1 x 1 1 x 1 1 1 x 1 1 x x 1 1 1 1 1
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Incremental Technology Maturation
• A successful ISS laboratory for technology maturation allows technology maturation to transition smoothly between 1-g development and the microgravity operational environment in terms of cost, complexity, and risk.
• Technology maturation is essential to advancement of space technologies
• Need to provide “smooth” path– Current “Technology Readiness Levels” (TRL) results on
steep increases from ground tests (TRL 1-4) to space environment demonstrations (TRL 5-7) and flight operations (TRL 8-9)
– Jump in complexity between TRL’s creates high-risk environments; cost of potential loss is very high
– Use human presence in space to reduce risk
TRL 1-2: Basic principles & conceptTRL 3-4: Proof-of-concept & laboratory breadboardTRL 5: Component validation in relevant environmentTRL 6: System prototype demonstration in relevant environmentTRL 7: System prototype demonstration in space environment
(usually skipped due to cost)TRL 8: Flight system demonstration in relevant environmentTLR 9: Mission Operations
TRL
1 2 3 4 5 6 7 8 9
ComplexityRiskCost
Now with ISS
ISS Projects
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Incremental Technology Maturation
• Metric/Evaluation:– Use TRL definitions to determine how close the facility allows a technology to reach a representative (TRL 5/6)
and/or space environment (TRL 7)– Evaluate the cost of using the ISS as compared to testing the technology directly in a space environment
• Define a cost for the risk:
• Define a total cost for each step:
• Determine success of using ISS:
GND
ISS
Flight
$1Risk1
$2Risk2
$3Risk3
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Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES Principle of Requirements Balance
• The requirements of a laboratory are balanced such that one requirement does not drive the design in a way that it hinders the ability to succeed on other requirements; further, the hard requirements drive the majority of the design, while soft requirements enhance the design only when possible.
– All the previous principles will create different, but not necessarily independent, requirements
• A successful project balances all its requirements so that no single one overshadows all others
• Balancing the requirements ensures that all the other principles are accounted for and met as best as possible/viable
– There are hard and soft requirements• Hard requirements are usually set at the start of a project to determine the goals that must be
met; they are mostly quantitative
• Soft requirements are features desired by the scientists but which do not necessarily have a specific value or which are not essential for the success of the mission
– Maximize the ratio of hard requirements to soft requirements• Minimize the chance of bloating the facility with unused features
Results
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES SPHERES: Iterations Efficacy
• Simulation: multiple iterations, flexible turnaround• SSL Off-site: multiple iterations, with turnaround of
days• SSL On-site: multiple iterations with hours-to-days
between iterations• KC-135: several iterations with fixed one-day period• KC-135: one iteration between each campaign• MSFC: perform multiple iterations with flexibility in
hours/days• MSFC: one iteration between each campaign• ISS: expected multiple iterations with turnaround in
increments of two weeks
MSFC-2
Simulation
EffectiveIterativeResearch
IneffectiveIterativeResearch
Time between iterations i
Nu
mb
er
of
itera
tion
s
KC-135-2
KC-135-1
MSFC-1
ISSSSL-on
SSL-off
Step Location 1 2 3 4 Comments
Simulation Researcher Minutes Researcher Hours Low fidelity MIT SSL – Off Site 20 min Hours Researcher Days SPHERES team member
runs tests MIT SSL – On Site 20 min Minutes Travel Minutes Maximum level of
support KC-135 20 sec Hours 24-72
hours Minutes Challenging
environment MSFC 10 min Minutes
/Hours Hours /Days
Minutes Possibility of two iterative loops: on site and at remote location
ISS 30 min 2 days 2-4 weeks 2 days Analysis time in increments of 2 weeks
Space Systems Laboratory Massachusetts Institute of Technology
SPHERES
• Evaluation Framework– Created to allow a member of the NGO or NASA team to evaluate a design to
determine:• Correct utilization of the ISS• Technology advancement• Mission scope
– Based on six principles:• Iterative Research
• Enabling a Field of Study
• Optimized Utilization
• Requirements Balance solely part of the design framework
Evaluation Framework