Design and Evaluation of an Orbital
Debris Remediation System
Collision
Risk
Design Evaluation
1. Object Categorization
Remediation
Designs
2. Network Analysis
Debris
Remediation
Systems
3. Utility Analysis
Strategy
Recommendations
1
Agenda
• Context Analysis
– Current Environment
– Space Debris Risk
– Remediation Efforts
•
•
•
•
•
Stakeholder Analysis
Problem Statement
Concept of Operations
Method of Analysis
Project Plan
2
Background
• A satellite is an artificial
object placed in orbit
around the earth
• Types of orbit:
– LEO: 0-2000 km, 7.6
km/s
– MEO: 2000-35,780 km,
3.8 km/s
– GEO: 35,780 km, 3 km/s
Source: ESA, 2003
3
Uses and Revenue
Operational Satellites by Function and Global Satellite Industry Revenues
Source: SIA SSIR, 2015
4
Development and Launch Costs
• Development costs: from $7,500 (Cubesat) to $2.2 billion
(Envisat)
• Launch costs:
– Satellite masses range from 1 kg to 18,000 kg (UCS)
– ~$4,500/kg (NASA Marshall Center)
5
Space Debris Risk
• 1.285 kg satellite
impacted by a 39.2 g
projectile at 1.72 km/s
• 1500 fragments
produced
Source: NASA, JSC, 2007
𝐸𝑖𝑚𝑝
𝐸𝑖𝑚𝑝 = 𝑖𝑚𝑝𝑎𝑐𝑡 𝑒𝑛𝑒𝑟𝑔𝑦
𝑀𝑝 ∗ 𝑉𝑖𝑚𝑝 2 39.2 𝑔 ∗ (1.72 𝑘𝑚/𝑠)2
=
=
= 57.98 𝐽𝑜𝑢𝑙𝑒𝑠
2
2
6
Space Debris Risk
• Kessler Syndrome: a domino effect that could
render space systems unusable due to
dangerous flight conditions
7
Space Debris Risk
• State-sponsored active anti-satellite measures
– Chinese ASAT missile, 2007
• Random collisions, explosions, and malfunctions
– Iridium 33 and Cosmos 2251, 2009
Debris Cloud 3 Hours Post Collision
Debris Cloud 27 Months Post Collision
Source: T.S. Kelso, 2013
8
History of Remediation Effort
1960’s-80’s
1980’s-2000’s
2010’s-today
Future
• First identified as a problem in the 1960’s
• United Nations Office of Outer Space
Affairs (UNOOSA) published 7 guidelines in
2007 to enforce total lifecycle planning
• Remediation still needs to take place
9
Dynamic System Model
• 𝑂 = 𝑎𝐶𝑂2 + 𝑏𝐿𝐴 + 𝑐𝐿𝐵 −
𝑑𝑃𝑀𝐷 − 𝑒𝑁𝐷 − 𝑓𝐷𝑅𝑆
•
•
•
•
•
𝐶 = 𝑔𝐶𝑂2 − ℎ𝐺𝐴 − 𝑖𝐺𝐵
𝐿𝐴 = 𝑗𝐿𝐴 𝐺𝐴 − 𝑘𝑂
𝐺𝐴 = 𝑙𝐿𝐴 𝐺𝐴 − 𝑚𝐶
𝐿𝐵 = 𝑛𝐿𝐵 𝐺𝐵 − 𝑜𝑂
𝐺𝐵 = 𝑝𝐿𝐵 𝐺𝐵 − 𝑞𝐶
10
Active Debris Removal
• ADR Concept of Operations:
1.
2.
3.
4.
Identify the target object
Maneuver and rendezvous with target
Grapple with target and de-tumble if necessary
Remove the object(s) from orbit
• There are many different implementations of
the same idea
11
ADR Alternatives
Active Debris Removal
Concept
TRL
Cost
Physically grab the debris object using a robotic arm and
perform a maneuver to change the object’s orbit.
6-7
High
6-7
Low
5-6
Medium
Three Coordinated
Electromagnetic Spacecraft
With the application of inter-spacecraft electromagnetic
force, disabled satellite with functional magnetorquer
can be removed in a non-contacting manner without
propellant expenditure and complicated docking or
capture mechanisms.
2-4
High
Harpoon
Shoot a tethered harpoon into the object. After the
harpoon penetrates the object, the bars at the point are
opened to keep itself sticking in the object. Then
perform a maneuver to change the object’s orbit.
6-7
Medium
Eddy Currents
It is based on the computation of the Magnetic Tensor
which depends on how the conductive mass is
distributed throughout the debris object, using the open
cylindrical shell and flat plates. No mechanical contact
with the target is required since an active de-tumbling
phrase is based on eddy currents. The study targets an
Ariane H10 upper stage (R/B).
3-4
High
Robotic arm (with de-orbit
kit)
Throw Net
COBRA IRIDES
Throw a net towards a debris object and pulls the object
along a tether. The net entangles the objects due to
masses or a closing mechanism.
Use plume impingement from a hydrazine
monopropellant propulsion system to impart
momentum on a target debris either to change its orbit
or its attitude.
12
Agenda
• Context Analysis
• Stakeholder Analysis
– Objectives
– Relationships
– Tensions
•
•
•
•
Problem Statement
Concept of Operations
Method of Analysis
Project Plan
13
ADR Implementation
Triggers
Increases in
debris
population
Decreases
in space
safety
Phase I : Pre-launch
Research,
collect data
and present
proposals
Approve space
policy and
provide
fundings
Phase II : Launch
Determine
launch type
Determine
launch site
Approve
space policy
politically
Design and
build
spacecraft
Phase III : In-orbit life
Monitor
progress
Cover
launching risk
Surveil space,
and detect
movement
Dispose at
end-of-life
Provide
launch
services
Increases in
satellite
demand
Evaluate
spacecraft
Insure
spacecraft
National government
Commercial industry
Civil organizations
14
Stakeholder Relationships
National Governments
Russian
Political
issue
Civil Organizations
Financial issue
United
States
NASA
Approve space policy, and provide
funding
Research, collect data and
provide overall guidance
China
ESA
IADC
Europe
RFSA
CNSA
Commercial industry
Build, design and
support rockets,
spacecrafts and
satellites. Also,
provides
spacecraft launch
services.
System
Manufacturers
Contracts
Transport
Companies
Insurance
Companies
Contracts
Lockheed
Martin
SpaceX
Boeing
ULA
XL CATLIN
Build, design and
support rockets,
spacecrafts and
satellites. Also,
provides spacecraft
launch services.
STARR
Airbus
Orbital
Sciences
Tensions
Objectives
15
Agenda
• Context Analysis
• Stakeholder Analysis
• Problem Statement
– Gap Analysis
– Problem Statement
– Need Statement
• Concept of Operations
• Method of Analysis
• Project Plan
16
Gap Analysis
We don’t know how successful individual
ADR design alternatives may be or how best
to compare them to each other.
17
Problem Statement
There is currently no consensus on the best
strategy for orbital debris remediation.
18
Need Statement
There is a need for a rigorous,
comprehensive analysis of design
alternatives.
19
Agenda
•
•
•
•
Context Analysis
Stakeholder Analysis
Problem Statement
Concept of Operations
– Mission Requirements
– Functional Requirements
– Simulation Requirements
• Method of Analysis
• Project Plan
20
Mission Requirements
• MR.1 The DRS shall de-orbit at least 5 highrisk debris objects per year.
• MR.2 The DRS shall select high-risk objects as
a function of mass and collision probability.
• MR.3 The DRS shall focus remediation efforts
in LEO (below 2000 km).
21
Mission Requirements
• MR.4 The DRS shall not be intentionally
destroyed while in orbit.
• MR.5 The DRS shall release no more objects or
vehicles than it recovers.
• MR.6 The DRS shall allow end-of-life
passivation within 2 months.
22
Functional Requirements
• FR.1 The DRS shall be able to identify debris
objects larger than 10 cm in diameter.
• FR.2 The DRS shall be able to maneuver
throughout LEO (up to 2000 km).
• FR.3 The DRS shall be able to engage with
debris up to 8900 kg (dry mass of SL-16).
• FR.4 The DRS shall be able to remove debris
objects from orbit.
23
Simulation Requirements
• SR.1 The simulation shall output optimal network
paths for given parameters.
• SR.2 The simulation shall modify the optimal
network for different designs.
• SR.3 The simulation shall account for multiple
possible launch sites.
• SR.4 The simulation shall account for
combinations of ADR designs.
• SR.5 The simulation shall target objects with the
highest scores.
24
Agenda
•
•
•
•
•
Context Analysis
Stakeholder Analysis
Problem Statement
Concept of Operations
Method of Analysis
–
–
–
–
Object Categorization
Network Analysis
Utility Analysis
Design of Experiment
• Project Plan
25
Project Objective
Determine recommendations for best
strategies for the remediation of orbital
debris in terms of cost, risk, effectiveness,
and schedule.
26
Method of Analysis
27
Method of Analysis
1. Object categorization: effectiveness
distributions of ADR designs for types of
debris
2. Network analysis: shortest-path network
analysis for access and maneuvering to
debris
3. Utility analysis: quality (political viability,
path length, etc.) vs total life-cycle costs
28
1. Object Categorization
29
1. Object Categorization
• Object Types:
– Operational satellites
– Defunct satellites
– Rocket bodies
– Fragments
• Metrics:
– Mass
– Velocity
– Rotation
• Linear Decreasing:
– V(𝑋) = 1 −
𝑀𝑎𝑥−𝑋
𝑀𝑎𝑥−𝑀𝑖𝑛
• Exponential
Decreasing:
– V(𝑋) = 𝑒 −𝜆𝑋
30
1. Object Categorization
31
1. Object Categorization
Object
Net
Mass Velocity Rotation
ID
Score
ADR Design
Net
Harpoon
PacMan
Robotic Arm
3 Coordinated
EM
COBRA IRIDES
Operational Satellites
Mass
Velocity Rotation
Min Max Mean (1/𝜆) Mean (1/𝜆)
0.1 1500
2
1
4 2000
3
2
0.5 500
1.5
1.5
1 2250
0.7
2.2
0.1 4000
1 5000
4
3
3
3.4
11111
11112
11113
11114
11115
11116
11117
11118
11119
11120
11121
11122
11123
11124
153
35
5
195
16
77
2
164
48
184
97
118
32
167
8
4
6
3
7
3
1
7
2
1
8
3
3
5
4
0
2
1
3
3
3
4
5
4
5
3
5
5
0.139
1.159
0.188
0.721
0.091
0.324
0.658
0.158
0.407
0.747
0.090
0.352
0.251
0.200
Harpoon
Score
1.199
1.560
1.425
1.413
1.325
1.218
1.086
1.189
1.004
0.950
1.147
1.206
1.070
1.094
32
2. Network Analysis
33
2. Network Analysis
• Objective Function:
– 𝑀𝑎𝑥 𝑆𝑐𝑜𝑟𝑒 =
𝑛
𝑚
(
𝑖
𝑗 𝑂𝑏𝑗𝑒𝑐𝑡𝑆𝑐𝑜𝑟𝑒𝑗 −𝐿𝑎𝑢𝑛𝑐ℎ𝐶𝑜𝑠𝑡𝑖 −∆𝑉𝐶𝑜𝑠𝑡𝑖 )
• Variables:
– 𝑥𝑖𝑗 𝑡 = 𝑎𝑟𝑐 𝑓𝑟𝑜𝑚 𝑛𝑜𝑑𝑒 𝑖 𝑡𝑜 𝑗 𝑎𝑡 𝑡𝑖𝑚𝑒 𝑡
• Constraints:
–
–
–
𝑛
𝑖 𝑂𝑏𝑗𝑒𝑐𝑡𝑠𝑅𝑒𝑎𝑐ℎ𝑒𝑑𝑖 ≥ 5 ℎ𝑖𝑔ℎ 𝑟𝑖𝑠𝑘 𝑜𝑏𝑗𝑒𝑐𝑡𝑠
𝑛
𝑖 𝑂𝑏𝑗𝑒𝑐𝑡𝑠𝑅𝑒𝑎𝑐ℎ𝑒𝑑𝑖 ≤ 𝑀𝑎𝑥 𝑃𝑎𝑦𝑙𝑜𝑎𝑑 𝑜𝑓 𝐷𝑒𝑠𝑖𝑔𝑛
𝑛
𝑖 𝑂𝑏𝑗𝑒𝑐𝑡𝑆𝑐𝑜𝑟𝑒𝑖 ≥ 0.7 ∗ 𝑚𝑎𝑥𝑂𝑏𝑗𝑒𝑐𝑡𝑆𝑐𝑜𝑟𝑒
34
2. Network Analysis
35
2. Network Analysis
0
𝑥12 (𝑡)
⋯ 𝑥1𝑛 (𝑡)
𝑥21 (𝑡)
0
• 𝑋 𝑡 =
⋮
⋱
⋮
𝑥𝑚1 (𝑡)
⋯
0
• 𝑥𝑖𝑗 𝑡 = ∆𝑉 𝑐𝑜𝑠𝑡 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 𝑜𝑏𝑗𝑒𝑐𝑡𝑠 𝑖 𝑎𝑛𝑑 𝑗
• These matrices vary over time depending on
where the objects are in space
36
3. Utility Analysis
37
3. Utility Analysis
38
3. Utility Analysis
Weights
Object
Score
Path
Length
Risk TRL
Political
Viability
0.106
0.144
0.306 0.2
0.244
Alt1
10.5
8
3.6
7
4.5
Alt2
8.4
9
5.6
6
6.5
Alt3
7.2
6
5.2
5
4.5
U(t) LCC
5.8
646
6.6
86
5.3
164
39
Design of Experiment
Network Constraints
Min Object Min
Experiment
Score Reached
E1
0.7 of max
5
0.75 of
E2
max
5
E3
0.6 of max
5
0.65 of
E4
max
5
…
Utility Function Weights
Object Path
Safety Reliability TRL Agreeability Verifiability
Score Length
0.106 0.144 0.156
0.15
0.2
0.119
0.125
0.106
0.106
0.144 0.156
0.144 0.156
0.15
0.15
0.2
0.2
0.119
0.119
0.125
0.125
0.106
0.144 0.156
0.15
0.2
0.119
0.125
40
Agenda
•
•
•
•
•
•
Context Analysis
Stakeholder Analysis
Problem Statement
Concept of Operations
Method of Analysis
Project Plan
–
–
–
–
–
WBS
Budget
Earned Value Management
Critical Path
Project Risks
41
WBS
42
Budget
• We estimate 1275 hours of work on this
project from beginning to end.
• At $30 per hour, this gives us a working
budget of $38,250.
• Using an overhead and profit multiplier of 2.0,
we come to an overall project budget for
$76,500.
43
CPI/SPI
44
EV
45
Critical Path
46
Project Risks
Risk
Quantitative requirements
elicitation
Political feasibility metrics and
calculations
Acquiring datasets
Modeling (coding)
Verification of accuracy
Description
Stakeholders are not
forthcoming with
requirements
Determining a solid,
quantifiable metric for
political feasibility is not
simple
Datasets can be unreliable,
using differing definitions, or
sometimes wholly
contradictory
Modeling complex orbital
networks may prove
technically difficult
Mitigation Strategy
Develop requirements
independently and later ask
for verification
Make contact with political
insurance underwriters to
gain further knowledge
Prepare for a large amount of
data cleaning before use
Further research into
feasibility, previous similar
work, and discussion with
experienced SEOR faculty
The time scale for our project Be honest with this weakness
is too long for any immediate in our presentation of data,
verification of results
and include generous error
bounds where appropriate
47
Future Work
• Data collection on ADR designs for effectiveness
distributions
• Collect latest information on orbital population
– Object Categorization metrics
– Object trajectories
• Data collection on X(t) matrices (time-sensitive
arc lengths)
• Explore expansion of parameters for DoE
• Implement model designs in code
48
BACKUP SLIDES
49
Debris Risk
• Risk = Probability x Severity
– Space Debris Risk = Collision Probability x Mass
– Mass has an effect on damage caused and creation of debris
• Large number of small objects vs small number of large
objects
Source: D. Bensoussan, WSRF, 2012
50
Current and Proposed Systems
51
Stakeholders
National Governments
Commercial Industry
Civil Organization
USA
Transport companies
NASA
Russia
System manufacturers
RFSA
Europe
Insurance companies
ESA
China
CNSA
IADC
52
Stakeholders objectives
Process
Pre-launch
Objective
Stakeholder
1
Research, collect data, and
overall guidance
Civil
organizations
2
Approve space policy, and
provide fundings
National
governments
3
Agreement, verification
National
governments
4
Design and build spacecraft
Commercial
industry
53
Stakeholders objectives
Process
Prelaunch
Launch
In-orbit
life
Objective
Stakeholder
5
Assessment of spacecraft
design, and covering launch
risk
Commercial
industry
6
Determine launch type
Civil
organizations
7
provide launch services
Commercial
industry
8
Monitor progress
Civil
organizations
9
Space surveillance, and
detection of movement of
objects in space
Commercial
industry
54
Stakeholders Tensions
Type
Stakeholders
Tension
Political
Russia, U.S, EU
Russia has most debris,
and doesn’t want anybody
to remove it
Political
Russia, China
Some methods have dual use,
some countries would suspect
Political/Technical
international concern
Inaccuracy of falling objects in
some methods
Insurance, commercial industry
costs of risk management and
Commercial
Commercial
commercial companies
Insurance
Competitiveness
55
Stakeholders Tensions
Type
Stakeholders
Tension
Financial
Space agencies and
governments
Fundings
Civil organizations
IADC
Regulations about re-entry
controlled plan
All
Space agencies concerned,
while others want to make
profit in present time
Nature and probability
of collisions
56
Stakeholder Tensions
Type
Stakeholders
Problem
Political
Russia, U.S, EU
Russia’s debris
Political
Russia, China
Some methods have dual
use, some countries
would suspect
Political/Technical
International concern
Inaccuracy of falling
objects in some methods
Insurance, commercial
industry
Costs of risk management
by insurance companies,
while commercial
companies manage to
reduce costs
Commercial
57
Gap Analysis
Without remediation, the number of
objects and collisions will continue to
climb, even without additional launches.
Source: J. C. Liou, 2011
Source: AAS, 2010
58
Gap Analysis
Source: J. C. Liou, 2011
• 90% Post Mission
Disposal (PMD) does not
halt growth of population
• 90% PMD along with 2
high-risk objects removed
per year slows but does
not halt growth
• 90% PMD coupled with 5
high-risk objects removed
per year leads to a stable
environment
59
ADR Techniques
Robotic Arm
Robotic Arm with Deorbit Kit
Throw Net
Size/Maneuverability
Deployed length: 3.7m
80 kg
314 kg
Total area of 3,600
2
m connected to a
tether with a length of
70 m
Number of Debris
Payload
Single
Single
Single
Mass of Debris Payload
Up to 6,000 kg
Up to 7,000 kg
Up to 10,000 kg
COBRA IRIDES
Three Coordinated
Electromagnetic
Spacecraft
Single
Single
Factors
Risk
•
•
Power Generation
cannot offer a safe
removal of debris
target via controlled
entry
the limited time
available between
final burn and entry
for activities like
debris release, arm
retrieval and closing
of aft hatch
•
An estimated peak
power demand of
360W
Star-20 engine from
Alliant Techsystem Inc.
(ATK) and total impulse
of 722 kNs
complex and heavy
ADR payload design
•
failure of shooting a
net
60
Constraints
Object
locations
X(t)
matrices
Network
Analysis
Effectiveness
Distributions
Object
Scores
Utility
Analysis
61
62
63
64
65
66