A Comparison of Low Cost Transfer Orbits from GEO to LLO for a Lunar CubeSat Mission A presentation for the New Trends in Astrodynamics conference Michael Reardon 1, Jun Yu 2, and Carl Brandon 3 1 PhD Candidate, Department of Mathematics and Statistics, University of Vermont 2 Department of Mathematics and Statistics, University of Vermont 3 Department of Physics, Vermont Technical College mreardon@uvm.edu New York City, June 8, 2011
Introduction: What is a CubeSat? A CubeSat is a nanosatellite with the physical properties: dimensions: 10cm 10cm 10cm mass: < 1.33kg
Introduction: What is a CubeSat? A CubeSat is a nanosatellite with the physical properties: dimensions: 10cm 10cm 10cm mass: < 1.33kg Double 20 10 10cm and Triple 30 10 10cm CubeSats are also common.
Introduction: What is a CubeSat? A CubeSat is a nanosatellite with the physical properties: dimensions: 10cm 10cm 10cm mass: < 1.33kg Double 20 10 10cm and Triple 30 10 10cm CubeSats are also common. CubeSats are commonly constructed using basic kits and are then fitted with mission specific technology.
Introduction: What is a CubeSat? A CubeSat is a nanosatellite with the physical properties: dimensions: 10cm 10cm 10cm mass: < 1.33kg Double 20 10 10cm and Triple 30 10 10cm CubeSats are also common. CubeSats are commonly constructed using basic kits and are then fitted with mission specific technology. The Lunar Lander CubeSat project is a collaborative effort between students and faculty from four Vermont colleges and universities.
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing.
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing. The project was awarded a 2012 test launch to test communications and guidance system based on NASA s GEONS software
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing. The project was awarded a 2012 test launch to test communications and guidance system based on NASA s GEONS software With successful test, funding, and second launch opportunity, the full mission is planned for 2014
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing. The project was awarded a 2012 test launch to test communications and guidance system based on NASA s GEONS software With successful test, funding, and second launch opportunity, the full mission is planned for 2014 We are considering two possible propulsion systems:
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing. The project was awarded a 2012 test launch to test communications and guidance system based on NASA s GEONS software With successful test, funding, and second launch opportunity, the full mission is planned for 2014 We are considering two possible propulsion systems: 1. Low thrust electric-ion propulsion system (developed by JPL) 1mN of thrust I sp 3000s v budget of 3500 m/s
Mission Goals and Assumptions The goal of the project is to develop a triple CubeSat capable reaching lunar orbit and possibly conducting a lunar landing. The project was awarded a 2012 test launch to test communications and guidance system based on NASA s GEONS software With successful test, funding, and second launch opportunity, the full mission is planned for 2014 We are considering two possible propulsion systems: 1. Low thrust electric-ion propulsion system (developed by JPL) 1mN of thrust I sp 3000s v budget of 3500 m/s 2. Chemical propellant system (hydroxyl ammonium nitrate and methanol monopropellant) 4N of thrust I sp = 270s v budget of 2250 m/s
Modeling Goals and Assumptions Travel from 42,164 km GEO parking orbit to a 100 km circular LLO.
Modeling Goals and Assumptions Travel from 42,164 km GEO parking orbit to a 100 km circular LLO. Initial orbit epoch in the simulations is fixed at June 1, 2012
Modeling Goals and Assumptions Travel from 42,164 km GEO parking orbit to a 100 km circular LLO. Initial orbit epoch in the simulations is fixed at June 1, 2012 Maximum triple CubeSat wet mass of 4kg
Modeling Goals and Assumptions Travel from 42,164 km GEO parking orbit to a 100 km circular LLO. Initial orbit epoch in the simulations is fixed at June 1, 2012 Maximum triple CubeSat wet mass of 4kg Orbits are integrated with the Astrogator toolkit included in the STK software package which also allows for customized engine and physical design.
Modeling Goals and Assumptions Travel from 42,164 km GEO parking orbit to a 100 km circular LLO. Initial orbit epoch in the simulations is fixed at June 1, 2012 Maximum triple CubeSat wet mass of 4kg Orbits are integrated with the Astrogator toolkit included in the STK software package which also allows for customized engine and physical design. Orbits are locally optimized using the Design Explorer Optimizer package.
Direct Transfer to Lunar Orbit 2 Impulse Transfer based on Hoffman transfer 1. 1st impulse takes the CubeSat through the L1 gateway to a 100 km lunar periapsis. 2. 2nd impulse at lunar periapsis to circularize the lunar orbit.
Direct Transfer to Lunar Orbit 2 Impulse Transfer based on Hoffman transfer 1. 1st impulse takes the CubeSat through the L1 gateway to a 100 km lunar periapsis. 2. 2nd impulse at lunar periapsis to circularize the lunar orbit. Summary of Results Segment v (m/s) Time (days) 1 1039 4.8 2 738 - Total 1777 m/s 4.8
Direct Transfer Figure: Direct transfer to lunar orbit
Bi-Elliptical Transfer to Lunar Orbit 3 Impulse Transfer between two circular orbits of radius r i and r f.
Bi-Elliptical Transfer to Lunar Orbit 3 Impulse Transfer between two circular orbits of radius r i and r f. Can be more efficient that Hoffman transfer for certain ratios r f r i
Bi-Elliptical Transfer to Lunar Orbit 3 Impulse Transfer between two circular orbits of radius r i and r f. Can be more efficient that Hoffman transfer for certain ratios r f r i Adapted with proper timing to perform a lunar transfer: 1. 1st impulse takes the CubeSat on an elliptical orbit radius of apogee equal to 1.5 Lunar orbit radii ( 575, 000 km) 2. 2nd impulse at apogee to increase the radius of perigee to the lunar obit radius and differentially corrected to target a lunar periapsis of 100 km 3. 3rd impulse at lunar periapsis to circularize the orbit about the moon
Bi-Elliptical Transfer to Lunar Orbit 3 Impulse Transfer between two circular orbits of radius r i and r f. Can be more efficient that Hoffman transfer for certain ratios r f r i Adapted with proper timing to perform a lunar transfer: 1. 1st impulse takes the CubeSat on an elliptical orbit radius of apogee equal to 1.5 Lunar orbit radii ( 575, 000 km) 2. 2nd impulse at apogee to increase the radius of perigee to the lunar obit radius and differentially corrected to target a lunar periapsis of 100 km 3. 3rd impulse at lunar periapsis to circularize the orbit about the moon Summary of Results Segment v (m/s) Time (day) 1 1133 10.3 2 371 14.7 3 678 - Total 2182 25
Bi-elliptical Transfer Figure: Bi-elliptical transfer to lunar orbit
Quasi-Bi-elliptical Transfer to Lunar Orbit 3 Impulse Transfer 1. 1st impulse takes the CubeSat on an elliptical orbit radius of apoapsis equal to 1.5 Lunar orbit radii 2. 2nd impulse to adjust trajectory to intersect that of the moon 3. 3rd impulse at lunar periapsis to circularize the orbit about the moon
Quasi-Bi-elliptical Transfer to Lunar Orbit 3 Impulse Transfer 1. 1st impulse takes the CubeSat on an elliptical orbit radius of apoapsis equal to 1.5 Lunar orbit radii 2. 2nd impulse to adjust trajectory to intersect that of the moon 3. 3rd impulse at lunar periapsis to circularize the orbit about the moon Summary of Results Segment v (m/s) Time (day) 1 1123 9.4 2 30 5.4 3 792 - Total 1945 14.8
Quasi-Bi-elliptical Transfer Figure: Quasi-Bi-elliptical transfer to lunar orbit
Transfer via Lyopunov Manifolds 4 Impulse Transfer 1. 1st impulse takes the CubeSat to meet a point in configuration space coinciding with the stable manifold of a Lyopunov orbit 2. 2nd impulse adjusts the velocity to that of the manifold point 3. 3rd impulse upon arrival at the L1 orbit corrects velocity to ensure lunar capture and 100 km lunar periapsis upon leaving the L1 orbit. 4. 4th impulse at lunar periapsis to circularize the orbit about the moon
Transfer via Lyopunov Manifolds 4 Impulse Transfer 1. 1st impulse takes the CubeSat to meet a point in configuration space coinciding with the stable manifold of a Lyopunov orbit 2. 2nd impulse adjusts the velocity to that of the manifold point 3. 3rd impulse upon arrival at the L1 orbit corrects velocity to ensure lunar capture and 100 km lunar periapsis upon leaving the L1 orbit. 4. 4th impulse at lunar periapsis to circularize the orbit about the moon Summary of Results Segment v (m/s) Time (day) 1 677 1.6 2 851 28.3 3 3 9.4 4 635 - Total 2165 39.3
Transfer via Lyopunov Manifolds Figure: Lyopunov orbit manifolds in CRTBP
Transfer via Lyopunov Manifolds Figure: Transfer to lunar orbit via manifolds in CRTBP
Transfer via Lyopunov Manifolds Figure: Transfer to lunar orbit via manifolds
Low Thrust Transfer Low thrust transfer similar to the ESA SMART-1 mission 1. 1st series of thrust arcs near perigee to increase the radius of apogee 2. 2nd series of thrust arcs near apogee to raise the radius of perigee and ensure lunar capture 3. 3rd series of thrust arcs and spirals to stabilize the lunar orbit 4. 4th series of thrust arcs and spirals to circularize and decrease the orbit radius
Low Thrust Transfer Low thrust transfer similar to the ESA SMART-1 mission 1. 1st series of thrust arcs near perigee to increase the radius of apogee 2. 2nd series of thrust arcs near apogee to raise the radius of perigee and ensure lunar capture 3. 3rd series of thrust arcs and spirals to stabilize the lunar orbit 4. 4th series of thrust arcs and spirals to circularize and decrease the orbit radius Summary of Results Segment v (m/s) Time (day) 1 1157 183 2 150 8 3 450 19 4 910 155 Total 2667 365
Low Thrust Transfer Figure: Transfer from earth orbit to lunar orbit
Low Thrust Transfer Figure: Lunar spiral
Low Thrust Transfer Figure: Earth spiral Figure: Lunar spiral
Low Thrust vs High Thrust We have shown that both options can be used to produce viable trajectories subject to the constraints of this particular mission, each with their own advantages and disadvantages.
Low Thrust vs High Thrust We have shown that both options can be used to produce viable trajectories subject to the constraints of this particular mission, each with their own advantages and disadvantages. Low Thrust Ion Propulsion Advantages vs Chemical Propulsion: 1. Lower fuel mass requirements 2. Considered safer for launch with other satellites.
Low Thrust vs High Thrust We have shown that both options can be used to produce viable trajectories subject to the constraints of this particular mission, each with their own advantages and disadvantages. Low Thrust Ion Propulsion Advantages vs Chemical Propulsion: 1. Lower fuel mass requirements 2. Considered safer for launch with other satellites. Low Thrust Ion Propulsion Disadvantages vs Chemical Propulsion: 1. Longer transfer times. 2. Require larger battery/solar panels 3. Subject to thruster shutdown due to eclipsing 4. Not able to perform larger nearly instantaneous velocity corrections Figure: JPL Miniature Xenon Ion Thruster
Present and Future work Further optimization of both low and high thrust trajectories
Present and Future work Further optimization of both low and high thrust trajectories Transfers from initial GEO not in the lunar orbital plane
Present and Future work Further optimization of both low and high thrust trajectories Transfers from initial GEO not in the lunar orbital plane High thrust transfers 1. WSB Transfer 2. Transfer via large amplitude Lyopunov orbit families
Present and Future work Further optimization of both low and high thrust trajectories Transfers from initial GEO not in the lunar orbital plane High thrust transfers 1. WSB Transfer 2. Transfer via large amplitude Lyopunov orbit families Low thrust transfers 1. Take advantage of solar resonance 2. Incorporate deployable solar panels into the STK model to more accurately capture solar wind effects 3. Determine battery life and charging capabilities 4. Include power loss due to solar eclipsing
Acknowledgments/Questions Vermont Space Grant Consortium Analytical Graphics Inc.