FISO Colloquium
Texas Spacecraft Laboratory
SmallSat Applications and
Formation Flying Technologies
E. Glenn Lightsey
Professor
Dept. of Aerospace Engineering
and Engineering Mechanics
May 28, 2014
1
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Today’s Talk
• SmallSat Applications
– Background and Motivation
• SmallSat Formation Flying Technologies
– Sensing, Actuation, Communications, and
Control
2
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Who We Are
• A Research Lab at The
University of Texas at
Austin: the Texas
Spacecraft Laboratory
(TSL)
• 1 Faculty PI and a
Research Group of about
30 University students
(10 Graduate and 20
Undergraduate Students)
• And a startup company:
Austin Satellite Design, LLC
UT Tower is lit orange for ARMADILLO as winner
of national University Nanosatellite Program, 2013
Texas Spacecraft Laboratory
3
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
What We Do
• We propose, design, build,
test, obtain launches for,
and operate small satellite
“University Class” space
missions
• We advance, test, and
demonstrate space
technologies related to
small satellites and end-toend mission capabilities
• We conduct science
experiments and space
technology demonstrations
Bevo-2 Integration
3D Printed Thruster
LoneStar-1 Deployment
4
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Why Our Research Matters
• We are advocates for space use and
exploration, and for conducting scientific
and human operations in space.
• But, getting to space is hard.
• With our research, we hope to create a
future where space is more accessible and
routine for everyone.
5
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Why Going To Space Is Hard
Image: NASA
Mars Curiosity Rover
Image: spaceflightnow.com
Costs as much as:
(roughly)
Image: mohammaedjewelers.com
E. Glenn Lightsey
Texas Spacecraft Laboratory
6
The University of Texas at Austin
Texas Spacecraft Laboratory
Small Satellites, The Enabler
Standard 3-Unit CubeSat
Chipsat
CubeSat
Curiosity James Webb ST
Images: NASA
~30 cm
~10 cm
Small Satellites Mass-Cost-Time Relation
(from: Sandau et al., ISPRS Journal of Photogrammetry and Remote Sensing, 65, 2010)
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
The CubeSat Standard
Texas Spacecraft Laboratory
• Standardized platform for low-cost,
frequent access to space as a secondary
payload created by Twiggs (Stanford) and
Puig-Suari (Cal Poly)
• Over 100 CubeSats launched to date to
Low Earth Orbit (350-850 km range)
• Longest known lifetime: 8 yrs
Design
• 1U: 10 cm x 10 cm x 10 cm outer
dimensions, ~1.3 kg mass
• Sizes range from 0.5U to 3U in a standard
Cal Poly P-POD deployer
• 6U and larger microsatellite deployers are
being developed
Slide Credit: Matt Bennett and Andy Klesh
8
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Small Satellites, To Scale
Mars Curiosity Rover
CubeSat
30 cm,
4 kg
(10 lbs)
Image: NASA
4.5 m, 3900 kg (9000 lbs)
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Secondary Payload Launch Considerations
• Ridesharing provides space
access at fractional or no cost
• Can travel into orbits that would
otherwise be inaccessible (e.g.
GEO, Earth escape)
CubeSat Launcher (3U)
However:
• Limited flexibility to pick initial
orbit or launch date
• Must conform with deployer and
launch vehicle standards
ESPA Ring (Microsat)
PRIMARY
PAYLOAD
CubeSat
Dispensers
• Must pose minimal risk to
primary payload
• Usually require an intermediary
to work with the launch provider
ESPA-like Ring
10
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
What Types of Missions are
Possible with Small Satellites?
Texas Spacecraft Laboratory
• Hardware Demonstrations
• Capability Demonstrations
• Earth and Space Science
Missions
• Proximity Operations and On-orbit
Inspections
• Interplanetary and Deep Space
Missions
• Fractionated and Multi-point
Space Missions
(e.g. Swarms and Constellations)
• On-orbit Servicing, Repair, and
Assembly
Image: SSTL
Image: Lunarsail
Image: DARPA
Image: Lithuania World
E. Glenn Lightsey
Texas Spacecraft Laboratory
11
The University of Texas at Austin
Texas Spacecraft Laboratory
Your Cell Phone-A Satellite?
Our Satellite (ARMADILLO):
Your Cell Phone:
Image: electronics360.globalzone.com
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
NASA’s PhoneSat Missions
Launched on April 2013, November 2013
Photo of Test Flight
Image received
from PhoneSat
in orbit
Artist Rendering!
Image: vrzone.com
Cost of PhoneSat Hardware: $7,500
Images: NASA
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Commercial Ventures
Using Small Satellites
Satellite Suppliers
Texas Spacecraft Laboratory
Satellite Consumers
These Are Just Representative Examples – Many More Are Possible!
14
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Small Satellite Launch Projections
Image: SpaceWorks
Data based on announced programs only that were known in 2013.
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Today’s Talk
• SmallSat Applications
– Background and Motivation
• SmallSat Formation Flying Technologies
– Sensing, Actuation, Communications, and
Control
16
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Formation Flying Missions:
Past and Future
Texas Spacecraft Laboratory
A partial list of relevant missions
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EO-1 (NASA, 2000)
SNAP-1 (Europe, 2000)
GRACE (NASA, 2002)
DART (NASA, 2005)
XSS-11 (DOD, 2005)
Orbital Express (DOD, 2007)
ANDE (DOD, 2009)
FASTRAC (DOD, 2010)
Prisma (Europe, 2010)
TanDEM-X (Europe, 2010)
LoneStar-2 (NASA, ~2014)
Prox-1 (DOD, ~2015)
CPOD (NASA, ~2015)
QB50 (Europe, ~2015)
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Formation Flying
Technology Elements
Control
Texas Spacecraft Laboratory
Sensing
Actuation
Communication
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Sensing Considerations
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Measurement Accuracy
Active vs. Passive
Absolute vs. Relative
Dynamic Range of Operation
LEO vs. Beyond LEO
Real-time vs. Post Processed
Compatibility with Science
Measurement
• Technical Maturity and Availability
• Sensing Robustness and
Susceptibility to Measurement
Blackouts
• Size, Weight, Power and Cost
Example real-time navigation problem
Scientific result based upon
post-processed navigation (GRACE)
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Absolute Position Sensing in LEO
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Global Navigation Satellite Systems
(e.g. GPS, Galileo)
Need for low-cost navigation makes GNSS
receivers ubiquitous on LEO space craft
Absolute Nav in WGS-84 geodetic
reference frame
Performance unlikely to be matched by
any other comparable technology for
foreseeable future
Passive, LEO navigation sensor (up to
~1000+ km, higher with special systems)
Weak signal susceptible to self-induced
EMI, localized jamming
Real-time nav accuracy: meter-level
Post-processed accuracy:
decimeter/centimeter-level
Example CubeSat capable GPS
receivers (Novatel and FOTON)
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Absolute Position Sensing
Beyond LEO
Texas Spacecraft Laboratory
• Deep Space Network: traditional
comm beyond Earth orbit
– Requires scheduling dedicated
NASA resources
• Optical Navigation via planetary
imaging
NASA’s Deep Space Network
– Requires satellite be near a moon
or planet
– Accuracies are low (km-level)
50
100
150
• Future nav: X-ray pulsars?
200
250
– Timing of pulses acts like GPS
wavefronts for navigation
– Low Technology Readiness Level
– Questionable implementation on
CubeSats
300
350
400
450
500
550
100
200
300
Optical nav using star-horizon measurements;
an X-ray pulsar
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Relative Position Sensing
Differencing Methods
Texas Spacecraft Laboratory
GPS Satellite
• Differencing measurements allows
correlated errors to cancel, enabling
more accurate relative measurements
• Independent noise sources are rootsum-squared, increasing noise
• Overall accuracy depends on which
effect dominates
eloc
erem
rrem
rloc
remote
receiver
local
receiver
Dr
vrem
vloc
• Common timing is essential (GPS or
independent clock)
• GPS position fixes or raw
measurements (e.g. pseudorange and
carrier phase) may be differenced
• Problematic approach beyond Earth
orbit due to limited availability of a
common signal (e.g. GPS)
GPS relnav can achieve sub-meter accuracy
22
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Relative Position Sensing
One Way Ranging Methods
Texas Spacecraft Laboratory
• Potentially more accurate than
differencing methods
– E.g. GRACE Ku-band, micron-level
• Can work in combination with absolute
nav systems like GPS
• Can be customized to system design
• Some technology development
needed for CubeSat hardware
• Requires time synchronization (from
GPS or external clock)
• Satellite networks may use
overdetermined systems to improve
accuracy/robustness
GRACE is an example of a combined
GPS/Ku-band ranging system
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Relative Positioning Sensing
Optical/Infrared Methods
•
Texas Spacecraft Laboratory
Optical Comm can act as a one way
ranging signal
– Requires tighter pointing capability than radio
– Hardware non-existent for CubeSats
•
Visual nav may be either pose-based or
centroid-based
– Good accuracies (meter-level) are possible over
short distances (~100 m)
– Consider lighting conditions and optics
– Can detect motion (object identification), extract
velocity information
•
Infrared systems are centroid based with
longer range than visual
– As long as line of sight is maintained, can track
objects up to ~3 km
– Centroid/blob based motion detection and tracking
– Sensor technology still low TRLs for CubeSats
Optical, vision, and IR nav sensors
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Today’s Talk
• SmallSat Applications
– Background and Motivation
• SmallSat Formation Flying Technologies
– Sensing, Actuation, Communications, and
Control
25
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Actuation Considerations
• Some “formations” do not require
position-keeping; position knowledge
is all that is necessary
• If position-keeping is required
(relative or absolute), then actuation
of some type is required
• Actuation may be classified as
impulsive (instantaneous) or lowthrust (acts over time)
• Limited volume and power constrains
choice of actuators for CubeSats
• Simplicity, safety, and cost are also
design drivers
Example: CubeSat impulsive cold-gas
Thruster design occupies 0.5U of a 3U
volume
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Impulsive Actuation:
Cold Gas Thrusters
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Texas Spacecraft Laboratory
Cold-gas thrusters are only technology
available to provide impulsive actuation for
CubeSats
Rapid-prototype (SLA) design method
(demonstrated on MEPSI, 2006) seems
well-suited for CubeSat missions
Using refrigerants as low pressure saturated
liquid, propellants, ~100 m/s delta-v’s are
possible on 3U and 6U CubeSats
These are “green” propellants because they
do not involve toxic materials or chemical
reactions
Hydrazine or other chemical propellants
may be considered for higher delta-v
capacity at the expense of simplicity and
cost
Stereolithographic (SLA) cold-gas thruster
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Low Thrust Actuation:
Propulsive Thrusters
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Pulsed-plasma thrusters (PPTs) and Hall-effect
(ion) thrusters use solids (teflon) and inert gases
(xenon) to create low-thrust actuation
Such devices deliver small forces (e.g., ~1-100
microNewtons) over long periods of time to
achieve an integrated effect
For example, an orbit-raising maneuver could
occur over several years to escape Earth’s orbit
Any mission using these devices must consider
the time required and the implications for
spacecraft reliability (e.g. radiation)
Also consider high voltage effects and spacecraft
charging due to thruster operation
The lack of impulsive capability makes these
devices less useful for traditional formation flying
Texas Spacecraft Laboratory
Block diagrams for PPT and Hall
thruster; xenon gas plasma glow
28
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Low Thrust Methods in LEO:
Drag/Differential Drag
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Texas Spacecraft Laboratory
In LEO, can use the Earth’s atmosphere as an
actuator by changing vehicle’s cross section
along the velocity direction
Can be done with drag control panels (picture) or
by rotating the vehicle (attitude control)
Differential drag force can be used to maneuver
one vehicle’s position relative to another
Drag force only acts along velocity vector,
so out-of-plane perturbations must be controlled
using another method (e.g. thruster)
Potentially useful method of “free” control to
reduce mission total delta-v requirements
Time required to conduct maneuvers may be an
issue
Drag panel conceptual design; simulated
rendezvous using differential drag
29
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Low Thrust Actuation:
Solar Sails
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Low-thrust force derived from photons
bouncing off reflective material (e.g.
mylar)
To be efficient, material must cover a
large area and spacecraft is low mass
Solar sail deployment from a CubeSat
was demonstrated on Nanosail-D
(2011) and is planned on Lightsail-1
(~2015)
As a low thrust device, shares same
system advantages and
disadvantages as PPTs and Hall
thrusters
Control force is not possible in every
direction instantaneously, possibly
requiring another actuator
Could be used for maneuvering
beyond Earth orbit (e.g. at Lagrange
points)
Texas Spacecraft Laboratory
CubeSat deployed solar sail and Nanosail-D
30
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Attitude Determination and Control
• Another possible type of
formation flying
• CubeSat COTS integrated
ADC solutions exist, but most
are intended for LEO
External Sensors
Comment
Sun Sensor
0.1
available
Star Camera
0.01
in development/available
varies
used near planets/moons
Horizon Detector
Deep Space Network
Earth Sensor
1
0.1
requires NASA support
Earth orbit
Magnetometer
1
LEO
GPS
1
LEO
Actuators
Example: Integrated 1U 3-axis ADC
with thruster for 6 DOF control
Estimated
Accuracy
(degrees)
Estimated
Accuracy
(degrees)
Comment
Reaction Wheels
0.01
available
Impulsive Thruster
0.01
in development/available
Solar sails
1
in development
Torque Rods
1
LEO
31
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Today’s Talk
• SmallSat Applications
– Background and Motivation
• SmallSat Formation Flying Technologies
– Sensing, Actuation, Communications, and
Control
32
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Communications Architectures
Intersatellite
Communication Methods
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Short range wireless
Line of sight wireless
Ground station relay
Space based relay
Space based communications
network
Tradeoff Considerations
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Link distance
Link bandwidth
Frequency
Number of contacts
Data downlink
Size, weight, power
Required infrastructure
Derived requirements (e.g.,
power and pointing)
• Technical Maturity/Risk
• Cost
33
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Crosslink Communications
• Short Range Wifi
– Employs existing standards and COTS
components
– Low size, weight, power, cost
– Questionable survivability
– Limited Range (few km)
– Additional space-ground system required
• Long Range (LOS) Crosslink
Xbee Wifi transceiver
– Traditional space-ground radios
– Considerations: directionality of antennas,
transmit power requirement, cost
– Can also serve as space-ground link
• Multi-node communication methods must
be planned for formations to avoid
interference (e.g. time indexing, frequency
hopping, CDMA, FDMA)
Image: USU/SDL
L3 Cadet Radio
(flown on DICE)
34
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Relay Architectures
• Ground Station Relays
– Utilizes existing or new infrastructure
– Store and forward concept enables over the
horizon relays
– Requires simultaneous visibility to satellites
from multiple locations
– Can be improved after launch
– Cost could be a factor
Example ground station relay (OrbComm)
• Space based Relays
– Formation satellites relay messages to each
other
– Daisy chaining messages allows over the
horizon to comms to any satellite in the
network, provided each satellite can be seen
by one other
– Comm structure (frequency, format) would
have to be developed custom for each
mission
E. Glenn Lightsey
Texas Spacecraft Laboratory
Example space based relay (Artemis)
35
The University of Texas at Austin
Texas Spacecraft Laboratory
Space Based Comm Network
• Concept: Utilize existing space-based
commercial systems (e.g. Iridium, h<700
km) or future services (e.g. EDRS)
• Formation satellites use bent-pipe
services to provide messages to other
satellites
• Over the horizon capable
• Size, power, and range of the equipment
must be considered (too large or too
small)
• Amount of data transferred is a factor
• Only works in orbits where comm
networks exist (e.g. LEO)
• Availability of future services is
speculative
Astrium-proposed EDRS (ETA 2015)
DARPA’s F6 Vision of Comm Networks
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Today’s Talk
• SmallSat Applications
– Background and Motivation
• SmallSat Formation Flying Technologies
– Sensing, Actuation, Communications, and
Control
37
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Formation Flying Control Considerations
• Complexity
– Systems of systems (interconnection/coupling)
• Communication and Sensing
– Limited bandwidth, connectivity, and range
– What? When? To whom?
– Data Dropouts, Robust degradation
• Arbitration
– Team vs. Individual goals
• Resources
– Always limited, especially on a CubeSat
38
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Passively Stable Formation Flying
• Linearized orbit dynamics admit
passively stable solutions where
one or more satellites co-orbits
a circular reference orbit
• Satellites placed in these orbits
can maintain a planar
orientation relative to the
reference orbit
• Accounting for perturbations
requires the existence of a
control system
The satellite in the green orbit
co-orbits the reference red orbit
•
Using a passively stable
reference design can greatly
reduce actuation requirements
39
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Formation Architectures
• Leader/Follower Guided Systems
– Generally two satellites, stationkeeping, autonomous
rendezvous, swarms
• Centralized Control
– Centralized planning and coordination, global team
knowledge, fully connected network
• Distributed Control
– Local neighbor-to-neighbor interaction, action evolves
in parallel manner
40
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Biologically Inspired Examples
of Distributed Control
Flocking
Texas Spacecraft Laboratory
Schooling
Swarming
Herding
Local Interaction with limited information
Relay produces Collective Group behavior
Can modern controllers produce similar
dynamic behaviors?
41
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Collective Control
with a Dynamic Leader
• Dynamic Leader
Texas Spacecraft Laboratory
• Coordinated Control
– A physical agent, a location
of interest, or a desired
trajectory
– A group of agents tracks or
follows a dynamic leader in a
prescribed manner
• Swarm Control
Example robotic coordinated control with
a dynamic leader (“duck walk”)
– A group of agents moves
cohesively with a dynamic
leader while avoiding interagent collision
42
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Swarm Control
• Potential function Vij
function of each agent’s
pairwise distance with
other agents
Distance-based potential function
• Swarm control law for followers
Vij 

ui    sgn  j
 , i  1,.n;   0
i
i 

Simulated swarming motion based on algorithm
43
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Consensus Control
• Interact with local neighbors
to reach an agreement
• Applications: cooperative
timing, rendezvous,
formation control, attitude
synchronization, etc.
R
agent i
or target
location
Neighboring agents initial and
final co-orbiting positions
• UAV co-orbiting consensus
result achieved in practice
Reconstructed UAV formation
flying trajectories
44
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Consensus Example:
Attitude Synchronization
Texas Spacecraft Laboratory
Rigid Body Dynamics
1
1
1
qˆ     qˆ  q  , q     qˆ
i
i
2 i i 2 i i
2 i i
J     J   
i i
i
i i
i
 
Control Torque
 i  kG qˆ d qˆi  dGi   aij qˆ *qˆi  bij i   j 
j i
where kG, dG, aij, bij > 0;
qd is desired constant attitude and
q* is attitude error
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E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Containment Control
with Multiple Leaders
Texas Spacecraft Laboratory
• A group of followers is
driven by a group of
leaders to be in the
region formed by the
leaders with only local
interaction
• Applications: cooperative
herding, grouping,
maintaining a specified
shape or volume
Containment control of formation while
leader region is changing shape and moving
46
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Distributed Average Tracking
with Local Interaction
Texas Spacecraft Laboratory
• Behaves like centralized
control without the
communication requirements
• Each agent maintains its own
estimate of the average state
and shares that with neighbors
• Starting with separate initial
conditions, all agents approach
a common value in finite time
with only local interaction
• Example: All agents approach
a common trajectory despite
starting with different initial
conditions
47
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Formation Flying
Technology Elements
Control
Texas Spacecraft Laboratory
Sensing
Actuation
Communication
48
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
The Future:
On-Orbit Servicing and Assembly
Texas Spacecraft Laboratory
• Small satellites can be
building blocks that are
assembled on-orbit to form
functional groups
• Such satellite groups may
or may not be physically
connected
• On-orbit assembly of large
apertures and satellite
lifetime extension by
consumables servicing are
two possible applications
49
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
CubeSat Formation Flying Summary
• While challenges exist, it is possible • Enabling technologies should
continue to develop and become
to credibly propose missions
flight proven over the next
employing some type of CubeSat
decade, reducing mission cost
formation flying
and risk
• The fact that we can have a realistic
• CubeSat formation flying will
conversation about CubeSat
facilitate new missions which
formation flying shows how far
provide new functionalities at very
things have come in ~10 years
efficient price points
50
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin
Texas Spacecraft Laboratory
Conclusion
• Space is more accessible than • Contact information:
ever before with small satellites
– E. Glenn Lightsey
– [email protected]
– (512) 471-5322
• The University of Texas at
Austin’s Texas Spacecraft Lab
supports a wide range of
CubeSat, small satellite and
• Additional information:
related space missions from
– Faculty Research page:
design through operations
• Research topics are integrated
with and motivated by satellite
experiments
• http://lightsey.ae.utexas.edu
• Downloadable papers and
presentations
– Lab Facebook page:
• https://www.facebook.com/UTSatLab
• Lots of pictures and videos of
hardware and lab activities
(be sure to ‘Like’ us for updates!)
51
E. Glenn Lightsey
Texas Spacecraft Laboratory
The University of Texas at Austin