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Trajectory design of formation flying constellation for space-based solar power

Goel, Ashish and Lee, Nicolas and Pellegrino, Sergio (2017) Trajectory design of formation flying constellation for space-based solar power. In: 2017 IEEE Aerospace Conference. IEEE , Piscataway, NJ, pp. 1-11. ISBN 978-1-5090-1613-6.

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The concept of collecting solar power in space and transmitting it to the Earth using a microwave beam has appealed to the imagination of numerous researchers in the past. The Space Solar Power Initiative at Caltech is working towards turning this idea into reality, by developing the critical technologies necessary to make this an economically feasible solution. The proposed system comprises an array of ultralight, membrane-like deployable modules with high efficiency photovoltaics and microwave transmission antennas embedded in the structure. Each module is 60 m χ 60 m in size and in the final configuration, ∼2500 of these modules form a 3 km χ 3 km array in a geosynchronous orbit. As the constellation orbits the Earth, the orientation and position of each module has to be changed so as to optimize the angle made by the photovoltaic surface with respect to the sun and by the antenna surface with respect to the receiving station on Earth. We derive the optimum orientation profile for the modules and find that modules with dual-sided RF transmission can provide 1.5 times more orbit-averaged power than modules with single-sided RF transmission. To carry out the corresponding orbital maneuvers, an optimization framework using the Hill-Clohessy-Wiltshire (HCW) equations is developed to achieve the dual goal of maximizing the power delivered, while minimizing the propellant required to carry out the desired orbital maneuvers. Results are presented for a constellation with modules in fixed relative positions and also for a constellation where the modules execute circularized periodic relative motion in the HCW frame. We show that the use of these periodic relative orbits reduces the propellant consumption from ∼150 kg to ∼50 kg. This drastic reduction makes the propellant mass a significantly smaller fraction of the module's dry mass (370 kg), thereby solving a major technical hurdle in the realization of space-based solar power.

Item Type:Book Section
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URLURL TypeDescription
Lee, Nicolas0000-0001-5500-1324
Pellegrino, Sergio0000-0001-9373-3278
Additional Information:© 2017 IEEE. The authors thank Northrop Grumman Corporation for supporting this project. We also thank all other members of the SSPI team at Caltech for their valuable inputs. Inputs from Dr. Daniel Scharf were very useful in the design of the periodic relative orbits. Nicolas Lee was supported during this work by a postdoctoral fellowship from the W. M. Keck Institute for Space Studies.
Group:GALCIT, Keck Institute for Space Studies, Space Solar Power Project
Funding AgencyGrant Number
Northrop Grumman CorporationUNSPECIFIED
Keck Institute for Space Studies (KISS)UNSPECIFIED
Record Number:CaltechAUTHORS:20170614-164611614
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Official Citation:A. Goel, N. Lee and S. Pellegrino, "Trajectory design of formation flying constellation for space-based solar power," 2017 IEEE Aerospace Conference, Big Sky, MT, USA, 2017, pp. 1-11. doi: 10.1109/AERO.2017.7943711
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:78224
Deposited On:15 Jun 2017 21:02
Last Modified:15 Nov 2021 17:37

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