Johnson Space Center
Future in Space Operations (FISO)
Copernicus Trajectory Design and Optimization System
Jerry Condon Johnson Space Center / EG5 gerald.l.condon@nasa.gov 281-483-8173 1 Johnson Space Center
What is ? Johnson Space Center What is Copernicus?
• The Copernicus Trajectory Design and Optimization System represents a new and comprehensive approach to performing mission design, trajectory analysis and optimization. • Copernicus brings together the state-of- the-art in trajectory optimization techniques, visualization, an easy to use “Out of many trajectory optimization GUI, a library of key algorithms, and a programs I have used throughout the distributed (batch) processing capability years within and outside of NASA, into an integrated package. Copernicus is the only program that effectively combines the state-of-the-art • Stimulates the creativity of the user to optimization algorithms with a 3-D design and solve innovative trajectories. visualization environment, enabling the user to see the trajectories graphically • It’s a “one stop shopping” tool for as the problems are being solved.” interplanetary mission and trajectory Dr. Min Qu design optimization and analysis. Senior Analyst Analytical Mechanics Associates, Inc.
3 Johnson Space Center Features
• Multiple spacecraft and multiple propulsion systems within a single mission • Extensive range of missions • From simple to complex problems
• Extremely powerful, yet highly “The Copernicus software suite is usable a well-built and user-friendly tool that can handle many tough • Evolutionary and expandable mission design problems. … We highly recommend Copernicus • Innovative modular design using to any mission designers.” trajectory “building blocks” George H. Born Director, Colorado Center for Astrodynamics Research
4 Johnson Space Center Levels of Fidelity • Low fidelity High fidelity [within the same tool] • Scans/trade studies Detailed mission design • Impulsive Δv Optimized finite burn maneuvers • Circular planet orbits Real ephemeris (SPICE) • Evolutionary (DE) Gradient-based (SNOPT,…) • Patched conic model High fidelity force model
5 Johnson Space Center
Innovative modular design using trajectory “building blocks”
Single points (states) Impulsive + Coast arc
t0 tf t0 tf
Single points + impulsive maneuvers Finite burn maneuver
t0 tf t0 tf
Coast arc Impulsive + Finite Burn maneuvers
t0 tf t0 tf
Copernicus Building Blocks: Trajectory Segments 6 Johnson Space Center Building Blocks: Segments DV Seg 1 (Coast)
Initial Condition Seg 3 (Coast) State continuity constraint
Seg 2 (Low Thrust Flyby Seg 4 (Coast) Body 1 Finite Burn) Constraint
Body 2 • Multiple spacecraft and propulsion systems. Body 3 • Can inherit information from other segments. • Optimization variables and constraints Final constraint • Forward and backward propagation. Seg 5 (High Thrust • Many classes of problems can be modeled with Finite Burn) the segment concept. • There are many ways to solve the same Controls (Optimization Variables) + problem. Constraints + Objective Function = Optimization Problem 7 Johnson Space Center Reusability • Fundamental building blocks can be combined and reused as needed • Allows solution of new problems in the future • Reduces development time for new mission designs.
+ =
8 Johnson Space Copernicus Distribution Center
ARC GSFC JSC JPL, KSC, LaRC MSFC University of Washington Space MSNW Exploration Andrews Space Engineering
CSNR RIT OAI P&W ARC UC Boulder Iowa State SAIC GRC APL Innovative Orbital Naval Design Lockheed-Martin GSFC Postgraduate Aerojet Analytical Mechanics School Zero-Point Frontiers LaRC Associates Boeing Edwards AFB JPL General Dynamics Mississippi State Ga. Tech Aerospace MSFC SpaceWorks Enterprises Corporation UA-Tucson UT-Austin JSC Ad Astra Jacobs Odyssey KSC
9 9 Johnson Space Center
Development Johnson Space Development History Center 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 UT Prototypes
Text based Segment architecture Non-interactive 2-D graphics Parameter optimization Impulsive/finite burns
11 Johnson Space Development History Center 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 NASA/UT Co-Development
GUI added Developed OpenGL API (OpenFrames) for interactive 3-D graphics SPICE integration added Optimally controlled finite burn segments Release 1.0 (March 2006)
12 Johnson Space Development History Center 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 NASA Development
Comprehensive interface Constellation/Orion Projects [2006-2010] Substantial internal “engine” improvements NASA In-Space Propulsion Technology Version Control Program [2010-2011] Regression Testing of Updates Documentation Training Videos Release 3.1 (June 2012) Accreditation Currently working on Release 3.2 13 Johnson Space Copernicus Architecture Center
Main Program Copernicus Libraries
GUI User Inputs Mission Design Design Modifications Toolkit Library Numerical Feedback Celestial Mechanics Routines SPICE Interface Math Utilities Coordinate Transformations Binary File I/O Gravity Models
Engine Trajectory Segments Optimization Visualization Integration Batch Library Aid in Problem Set-Up Control Algorithms Distributed Processing Trajectory Solution Feedback Engine Models Automated Copernicus Runs “Real” Trajectory Insights Production Data Output
14 Johnson Space Center Scalable and Cross-Platform
Copernicus can be scaled from a single desktop or laptop computer using the Graphical User Interface (GUI) and visualization tools, to computer clusters where no user interaction or graphical feedback are required.
Laptop Desktop Cluster 15 Johnson Space Accredited Center
Copernicus completed the NASA/HQ requested Verification, Validation, and Accreditation process
16 Johnson Space Center
In Action Johnson Space Start of Problem Solution Center Johnson Space User Adjustment Center
19 Johnson Space Iteration Process Center
20 Johnson Space Converged Solution Center
21 Johnson Space LCROSS Mission Center
LRO/LCROSS Design Case Study
“Copernicus is an extremely valuable tool used by the LCROSS trajectory team to optimize the LCROSS trajectory. LCROSS has a very complicated orbit that is difficult to optimize using standard off the shelf tools. … Copernicus has been an invaluable tool for the LCROSS trajectory team.” Steve Cooley LCROSS Trajectory Design Lead
22 Johnson Space Constellation Program Center • Architecture evaluation • Trade studies (TLI, LOI, TEI) • Lunar Capability Concept Review (LCCR) • Copernicus changed the way we look at mission design
Lunar Free Return Trajectory
23 Johnson Space Orion Project (Lunar Missions) Center
• Copernicus used extensively for Orion vehicle design and performance • Databases developed to characterize Orion lunar missions over the entire planned operational lifetime. • Millions of optimized TEI-2 trajectories using Copernicus on a computing cluster.
TEI-3 TEI-1
Three-Burn Trans-Earth Injection Maneuver Sequence 24
Johnson Space Abort Analysis Center
Multiple trajectories/spacecraft Mission specific targeting Orbit period Batch processing 50%: 0.29 days 25%: 2.9 days post partially failed LOI coasting Nominal trajectory
Fly-by return Nominal trajectory
Direct return Direct return
Moon-centered view Earth-centered view 9 Johnson Space In Space Propulsion Technology Project Center
ISP Reference Mission 28: Earth-Moon low thrust
“Copernicus has been an asset to NASA’s In-Space Propulsion project. Copernicus is used routinely for mission trades and to establish requirements and quantify benefits of advanced technology.” John Dankanich Lead Systems Engineer Gray Research (NASA/GRC) 26 Johnson Space VASIMR Center
“Our project has made extensive use of this excellent tool to design many of our most interesting mission scenarios. As the development of high power in-space electric propulsion matures, this sophisticated program can open and examine unique operational scenarios with both constant and variable specific impulse.” Franklin Chang Diaz Chairman and CEO Ad Astra Rocket Company 27 Johnson Space Center Ongoing Explorations Studies
Low thrust transfer to a lunar distant retrograde orbit
2009 HC Transfer in 2025
Round trip to L1 and L2 Halo Orbits 28 Johnson Space Quantum Vacuum Thruster Center
Mission to Mars Mars Arrival
Earth to 1000 AU
Mars Position at Spacecraft mass = 90 t Spacecraft mass = 90 t Start of Transit time = 2-6 years Transit time = 75 days Trajectory 1000 AU
LEO Spiral
Earth to Proxima Centauri Interstellar Note: Voyager 1, launched in September, 1977 (36 years ago) is currently around 125 AU away
Spacecraft mass = 90 t Transit time = 30-123 years
Proxima Centauri 29 Johnson Space Center Asteroid Tour Mission Design
GTOC-4: 32-Asteroid Intercept with Final Rendezvous (10 years)
GTOC-5: 15-Asteroid Rendezvous- Intercept (15 years)
30 Johnson Space Halo Orbit Transfers Center
ISP Reference Mission 31: Earth-Sun Libration Point Transfer Options to Earth-Moon L2 Halo Orbit
2 days 3 days 4 days 1 day
5 days
L2 6 days Direct
Earth Moon L2 Halo 2 days 1 day 3 days 6 days 5 days 7 days 4 days 8 days Flyby Earth Moon Flyby L2 L2 Halo
30 days 20 days 40 days 10 days
5 days 90 days 50 days Moon’sDirect and Flyby Transfers to Earth- L2 Halo OrbitMoon L1 and L2 Libration Points 1 Low Energy Moon day 31 Flyby To Sun (Manifold) 60 days
Earth
80 days 70 days Johnson Space Weak Stability Boundary Center 2 days 3 days 4 days 1 day Lunar Capture Mission
5 days
L2 6 days Direct
Earth Moon L2 Halo 2 days 1 day 3 days 6 days 5 days 7 days 4 days 8 days Flyby Earth Moon Flyby L2 L2 Halo
Sun-Earth Halo Orbit Missions 30 days 20 days 40 days 10 days
5 days 90 days 50 days Moon’s L2 Halo Orbit 1 Low Energy Moon day Flyby To Sun (Manifold) 60 days
Earth
80 days 70 days
Lunar Halo – Cargo Mission 32 Johnson Space Lunar Missions Center
Three-Burn Trans-Earth Injection Maneuver Sequence
Lunar Mission With Landing and Stage Disposal
33 Johnson Space Mars Mission Studies Center
ISP Reference Mission 12: Mars Sample Return Mission [Using low thrust engine and optimal control theory]
Mars Flyby Earth Departure
Earth Arrival
2018 Mars Free-Return Mars Flyby 34 Johnson Space Low Thrust Trajectories Center
ISP Reference Mission 16: Low Thrust Insertion into Polar Solar Orbit
Flexible Thruster Models
Halo Orbit to Near Rectilinear 35 Halo Orbit Transfer Johnson Space Center Asteroid Redirect Mission
Crewed missions to asteroid in lunar DRO
Asteroid transfer to DRO storage orbit
Final lunar flyby
Final DRO Insertion
36 Johnson Space Center Outer Planet Trajectory Design
ISP Reference Mission 8: Earth/Venus/Venus/Jupiter/Pluto flyby mission
37 Johnson Space Center Copernicus in Academia • University technical instruction and research • Makes spacecraft trajectory design accessible to a much wider audience • Inspires the interest and creativity of the next generation of engineers and scientists
38 Johnson Space Center Award History / JSC
• June 14, 2007: Space Act Award • 2009 JSC Exceptional Software Award • 2009 NASA Agency Software Of The Year – Runner Up
39 Johnson Space Center Development Future
• Copernicus is actively being developed and improved at JSC • Continued “engine” evolution • Incorporation of new guidance, targeting, and optimization algorithms • New models: integrators, ephemerides, atmosphere, etc. • New ways to solve complex trajectory design problems. • Continued GUI and visualization evolution • Drag and drop trajectories • Increased user-friendliness • Operations support
40 Johnson Space Center Obtaining Copernicus
•Copernicus is available to all NASA employees, government contractors, universities, and private businesses with NASA contracts.
•Contact: [email protected]
41 Johnson Space References Center
• For more information about Copernicus: • C. A. Ocampo, "An Architecture for a Generalized Trajectory Design and Optimization System", Proceedings of the International Conference on Libration Points and Missions, June, 2002. • C. A. Ocampo, "Finite Burn Maneuver Modeling for a Generalized Spacecraft Trajectory Design and Optimization System", Annals of the New York Academy of Science, May 2004. • J. Williams, J. S. Senent, C. A. Ocampo, R. Mathur, "Overview and Software Architecture of the Copernicus Trajectory Design and Optimization System", 4th International Conference on Astrodynamics Tools and Techniques, May 2010. • J. Williams, J. S. Senent, D. E. Lee, "Recent Improvements to the Copernicus Trajectory Design and Optimization System", Advances in the Astronautical Sciences, 2012. • Various studies that have used Copernicus • C. L. Ranieri, C. A. Ocampo, "Optimization of Roundtrip, Time-Constrained, Finite Burn Trajectories via an Indirect Method", Journal of Guidance, Control, and Dynamics, Vol. 28, No. 2, March-April 2005. • M. Carn, M. Qu, J. Chrone, P. Su, C. Karlgaard, "NASA’s Planned Return to the Moon: Global Access and Anytime Return Requirement Implications on the Lunar Orbit Insertion Burns", AIAA/AAS Astrodynamics Specialist Conference and Exhibit, August, 2008. • J. Williams, E. C. Davis, D. E. Lee, G. L. Condon, T. F. Dawn, "Global Performance Characterization of the Three Burn Trans-Earth Injection Maneuver Sequence over the Lunar Nodal Cycle", Advances in the Astronautical Sciences, Vol. 135, 2010. AAS 09-380 • A. V. Ilin, L. D. Cassady, T. W. Glover, M. D. Carter, F. R. Chang Diaz, "A Survey of Missions using VASIMR for Flexible Space Exploration", Ad Astra Rocket Company, Document Number JSC-65825, April 2010. • J. W. Dankanich, B. Vondra, A. V. Ilin, "Fast Transits to Mars Using Electric Propulsion", 46th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, July 2010. • J. S. Senent, "Fast Calculation of Abort Return Trajectories for Manned Missions to the Moon", AIAA/AAS Astrodynamics Specialist Conference, August 2010. • A. V. Ilin, L. D. Cassady, T. W. Glover, F. R. Chang Diaz, "VASIMR Human Mission to Mars", Space, Propulsion & Energy Sciences International Forum, March 15-17, 2011. • J. Brophy, F. Culick, L. Friedman, et al., “Asteroid Retrieval Feasibility Study,” Technical Report, Keck Institute for Space Studies, California Institute of Technology, Jet Propulsion Laboratory, April 2012. • P. R. Chai, A. W. Wilhite, "Station Keeping for Earth-Moon Lagrangian Point Exploration Architectural Assets", AIAA SPACE 2012 Conference & Exposition, September, 2012, AIAA 2012-5112. • J. Williams, "Trajectory Design for the Asteroid Redirect Crewed Mission", JSC Engineering, Technology and Science (JETS) Contract Technical Brief JETS-JE23-13-AFGNC-DOC-0014, July, 2013.
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Copernicus: The Movie
http://www.youtube.com/watch?v=uRKlB3G3Q-M
Johnson Space Center
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