Accurate State Uncertainty Propagation for a Spacecraft in the Cislunar Regime

Open Access
- Author:
- Glenn, Andrew
- Area of Honors:
- Aerospace Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Puneet Singla, Thesis Supervisor
Robert G. Melton, Thesis Honors Advisor - Keywords:
- Aerospace
Cislunar
Circular Restricted Three Body Problem
Conjugate Unscented Transform - Abstract:
- The main objective of this thesis is to study the propagation of uncertainty in orbit states of a spacecraft in the cislunar regime. Cislunar space is the region where the forces on a spacecraft are dominated by the gravity of the Earth and the Moon. This region is approximately twelve times the size of the geosynchronous Earth orbit (GEO) region. The dynamics and dynamical structures in cislunar space vary greatly from that of the GEO-domain. Gravitational acceleration in cislunar space is typically an order of magnitude smaller than in low Earth orbit. In some perspectives, this is advantageous, since less propulsion is needed to make large state changes. This also results in increased sensitivity to state errors, however. Nominal trajectories are more easily disturbed in the presence of model, navigation, and control errors. This work studies the application of various uncertainty propagation methods with the primary error in the velocity direction. The linear propagation method is compared to an optimal quadrature scheme known as the Conjugate Unscented Transformation (CUT). The CUT algorithms provide the optimal samples to compute statistical moments of desired order. Monte Carlo simulations are used to assess the accuracy of the uncertainty propagation methods. The extensive numerical simulations are conducted for a spacecraft in a Halo orbit around the second Lagrange point.