meetings - Space Flight Mechanics Committee

satellite orbiting the first lunar libration point. Linked Autonomous Interplanetary Satellite
Orbit Navigation (LiAISON) is used to calculate the orbit solution. This paper performs
high-fidelity simulations exploring the utilization of LiAISON in providing improved
accuracy for interplanetary departure missions. Comparisons with ground-based navigation
are explored to assess autonomous navigation of interplanetary spacecraft with respect to
supplementing current techniques. Results from simulations including the Mars Exploration
Rover, Mars Science Laboratory, and Cassini are presented.
10:45 AAS GOCE Fully-Dynamic Precise Orbit Recovery
13-285 Francesco Gini, Universita' di Padova; Francesca Panzetta, Universita' di Padova;
Massimo Bardella, Universita' di Padova; Stefano Casotto, Universita' di Padova
GOCE was launched in 2009 at 250 km altitude to recover Earth's static gravity field. As
part of the GOCE-Italy project, we carried out GPS-based, fully-dynamic POD of GOCE.
Daily arcs were computed for about 500 days (November 1, 2009 - May 31, 2011). Results
show an average post-fit RMS of zero-difference phase measurements of 8 mm. Most orbits
compare to less than 6 cm 3D RMS with respect to the official kinematic/RD PSO orbits.
These results form a solid basis for the reprocessing of GOCE tracking data for ocean tide
parameters solutions.
11:05 AAS Unscented Kalman Filter Robustness Assessment for Orbit Determination
13-208 Using GPS Signals
Paula C P M Pardal, ICT-UNIFESP; Helio Kuga, INPE; Rodolpho Moraes,
UNIFESP
In this work is presented the nonlinear unscented Kalman filter (UKF) evaluation for the
satellite orbit determination problem, using GPS measurements. The assessment is based on
the robustness of the filter. The main subjects for the evaluation are convergence speed and
computational implementation complexity, which are based on comparing the UKF results
against the extended Kalman filter (EKF) results for the same problem. After solving the
real time orbit determination problem using actual GPS measurements, through the EKF
and the UKF algorithms, the results obtained are compared in computational terms such as
burden (complexity), convergence, accuracy, and relative CPU time.
11:25 AAS Real Time Orbit Determination for Lunar and Planetary Missions
13-209 Ryo Nakamura, Japan Aerospace Exploration Agency
We develop a tool based on the Unscented Kalman Filter (UKF) for real-time orbit
determination for lunar and planetary missions. The UKF has an advantage over the EKF in
that they approximate the mean and covariance of state more accurately than EKF. The
developed tool is evaluated through the orbit determination simulations during orbit
insertion maneuvers of Japanese Venus Climate Orbiter “Akatsuki” and SELenological and
ENgineering Explorer “Kaguya”. The simulation results indicate that the tool works well
and the UKF is superior to the EKF in terms of both accuracy and stability of real-time orbit
determination.
23 rd AAS / AIAA Space Flight Mechanics Meeting Page 19