A Drag Device for Controlled Deorbiting of LEO Spacecraft. (aka Deorbit Drag Device = D 3 )

Transcription

1 A Drag Device for Controlled Deorbiting of LEO Spacecraft (aka Deorbit Drag Device = D 3 )

2 D 3 Team Members NASA Launch Services Program (LSP), Kennedy Space Center (KSC) Larry Fineberg (Integration Engineer) Justin Treptow (Flight Design Engineer) Yusef Johnson (Flight Design Engineer) Robert Kwas (Thermal Analysis Engineer) Brad Poffenberger (Payload Mechanical Engineer) Scott Clark (Project Manager) University of Florida Dr. Riccardo Bevilacqua (Principal Investigator) Associate Professor, MAE, UF (2014-current) Assistant Professor, Mechanical, Aerospace, and Nuclear Engineering, RPI ( ) Post-Doctoral Fellow, Naval Postgraduate School ( ) Dr. David Guglielmo (Post-Doctoral Research Associate) Ph.D., MAE, UF B.S. and M.S., Rensselaer Polytechnic Institute Sanny Omar (Graduate Research Assistant) Ph.D.candidate, MAE, UF B.S. (Summa Cum Laude), Auburn University AubieSat CubeSat team (flown via CubeSat Launch Initiative) Intern, SpaceX GN&C 2

3 Key Messages System modulates spacecraft drag force, controls orientation during orbital decay and targets re-entry location Goal: develop a simple, reliable, low-cost, non-propulsive system Application Object mass up to 180kg (~400 lb) CubeSats (as large as 12U) CYGNSS spacecraft ESPA Class spacecraft Orion 38 motor (depleted), such as spent Pegasus Launch Vehicle 3 rd stage Benefits Addresses a number of issues concerning CubeSats Space traffic management, orbital debris mitigation and satellite controllability Enable LEO spacecraft (altitudes up to 700km) to meet 25-year Orbital Debris requirement Avoid potential collisions; reduce liability and risk of generating new debris Provide ability to target unpopulated earth re-entry points Hardware or hazardous materials that survive ballistic entry Alleviate or mitigate risk of human casualty Ability to stagger CubeSat (or other spacecraft) constellations via differential drag force Improve ground radar visibility of spacecraft (greater surface area profile) Status Analysis and hardware prototype development nearly completed, currently at TRL 4 Jan 2017: projected ATP for design of a flight-ready 1U CubeSat Targeting flight opportunities in late CY18 via: CubeSat Launch Initiative, Venture Class launch vehicles, ISS deployment 3

4 D 3 Physics Orbit lifetime is dependent on: ballistic coefficient, atmospheric density, solar activity, earth and moon gravitational effects The ballistic coefficient of a spacecraft (C b = Area*C d /2*Mass), only variable we can control éballistic Coefficient à Orbit Lifetime ê D 3 modulates cross sectional area at specific times via variable boom deployment changes ballistic coefficient changes the atmospheric drag the spacecraft receives allows control altitude decay profile Atmospheric density on orbit varies significantly from what models predict Challenge is for D3 system to be robust enough to accommodate these variations Large ballistic coefficient variation Onboard computation and closed loop control system 4

5 Drag Device D 3 System for 3U CubeSat D 3 Booms à 0.5U Available Volume à 2U / 2-5kg Interface with Payload for Power Scalable to Small Spacecraft < 400lbs Booms provide 3-axis passive attitude control (drag plus gravity gradient) 5

6 D 3 Use Cases 1. Early Deployment Identification - CubeSat differentiation after deployment from large compliment 2. Orbital Lifetime Compliance (<25 years) - Allows SC compliance and higher altitudes to be reachable CubeSat with D 3 87 CubeSats to be launched on Formosat-5 6

7 D 3 Use Cases 3. Altitude Decay Control - Enable coordinated planned orbital decay, avoid active constellations (CYGNSS formation strategy) 4. Controlled Reentry / Targeted Impact Point - Provide Latitude and Longitude targeting for LEO small spacecraft - Variable position booms adjusted during final orbits to meet entry point target 5. Scalability - D3 System scales from 1U CubeSat up to 400lbm (180kg) Small Spacecraft Monte Carlo Analysis of D 3 Targeting Accuracy D 3 Applicable SC Classes 1U (1kg) 12U (12kg) Small SC (50kg) ESPA Class (180 kg) 7

8 Legal Considerations Why the D 3? Furthering free and open access and use of space for all Decluttering of orbits and increasing accessibility of more space Decreasing potential for harmful interference with other s space activities Decreasing the risks associated with orbital debris and increasing ability to maintain more control of the space craft while in outer space Liability/Risk Decreasing time in orbit decreases the amount of time for which fault-based liability under Art. III of the Liability Convention applies Decreasing likelihood of in-situ space collision Maneuvering more safely through orbits of other spacecraft Reducing the risk of absolute liability associated with damage caused by the returning space craft on earth under Art. II of the Liability Convention Distinguishing one spacecraft from another more easily in clusters 8

9 Legal Considerations What if it malfunctions? No change to the liability regime No change to the liability regime whether the device is successful or not Fault-based liability in space Absolute liability for damage on Earth Could pose issues with spacecraft, in higher orbits, which have limited maneuverability to avoid a collision If it malfunctions in a distant orbit, it will not meet the 25 year rule Early planning and specific modeling/testing can aid in mitigation Planning orbits for best and worst case scenarios 9

10 Legal and Practical Considerations This solution does not rely on propellant May take this out of ITAR and into EAR Less weight Reduces complexity No propulsion system Simplifies system integration Allows developers to utilize materials that are resistant to re-entry forces (titanium, tungsten, tantalum, etc.) Usage allowed because entry is targeted for unpopulated areas. Decreases probability of human casualty. This solution could potentially be used to identify specific spacecraft deployed in constellation, assisting the operator in forming the desired pattern This solution should decrease contingency planning budget Risk exposure for a fraction of the time Making reserve dollars available for more space activities Decisions on commercialization will be made as the technology matures 10

11 Conclusion D3 modulates spacecraft drag force & control orientation during orbital decay Testing is showing positive results Analytically demonstrated the D3 works Need to verify and validate the technology The deorbit targeting algorithm can be used to reduce casualty/property liability both in space and on earth Analysis shows the system can be scaled to larger bodies and the can stagger CubeSat (or other spacecraft) constellations via differential drag force Improve ground radar visibility of spacecraft (greater surface area profile) The system addresses a number of the issues concerning CubeSats: space traffic management, orbital debris mitigation and satellite controllability The use of this system will provide for a significant increase in potential CubeSat users by expanding the operational regime of these satellites. 11

12 Acknowledgments Sanny Omar, Dr. David C. Guglielmo, and Dr. Riccardo Bevilacqua (University of Florida) for their valuable work in establishing the technical basis for this investigation Tim Bass (Office of the Chief Counsel, Kennedy Space Center) for his legal analysis, leveraging off of his extensive education and practice in Space Law. His specific legal expertise with Small Spacecraft and the Launch Services Program was invaluable. LSP Programmatic Projects/Studies organization and ai solutions for sponsoring this investigation via NASA KSC subcontract (project LSP : A Drag Device for Controlled Deorbiting of LEO Spacecraft) Janet Karika (Executive Director, Interagency Launch Programs, Jacobs NASA Launch Services Program) for her valuable advice and recommendations Dr. Paul Schallhorn (Chief, Environments and Launch Approval Branch, Launch Services Program) for his insight & creative solutions 12

13 Publications Past Omar, S.R., Bevilacqua, R., Fineberg, L., Treptow, J., Johnson, Y., and Clark, S. Re-Entry Point Targeting for LEO Spacecraft using Aerodynamic Drag, Aerospace Control and Guidance Systems Committee Meeting #118, Oct Pérez, D., and Bevilacqua, R., Differential Drag-Based Reference Trajectories for Spacecraft Relative Maneuvering Using Density Forecast, Journal of Spacecraft and Rockets, vol. 53, Jan. 2016, pp , DOI: /1.A Omar, S. R., and Wersinger, J. M., Satellite Formation Control using Differential Drag, 53rd AIAA Aerospace Sciences Meeting, American Institute of Aeronautics and Astronautics,. Pastorelli, M., Bevilacqua, R., and Pastorelli, S., Differential-drag-based roto-translational control for propellant-less spacecraft, Acta Astronautica, vol. 114, Sep. 2015, pp. 6 21, DOI: /j.actaastro Pérez, D., and Bevilacqua, R., Neural Network based calibration of atmospheric density models, Acta Astronautica, vol. 110, May 2015, pp , DOI: /j.actaastro Guglielmo, D., and Bevilacqua, R., Propellant-less Atmospheric Differential Drag LEo Spacecraft (PADDLES) Mission, SmallSat Conference, Mason, C., Tilton, G., Vazirani, N., Spinazola, J., Guglielmo, D., Robinson, S., Bevilacqua, R., and Samuel, J., Origami-based Drag Sail for CubeSat Propellant-free Maneuvering, Tokyo, Japan: Future Omar, Sanny R. Dr. Bevilacqua, Riccardo. Spacecraft Re-Entry Impact Point Targeting using Aerodynamic Drag, University of Florida, ADAMUS Laboratory. AIAA SciTech, Jan 2017 Dave Guglielmo, Sanny Omar, Riccardo Bevilacqua, The Drag Deorbit Device (D3), in preparation for AIAA Journal of Spacecraft and Rockets Planning Stages Annual CubeSat Developers Workshop (April 2017) Small Satellite Conference (Aug 2017) AIAA Space Conference (Sept 2017) 13