Pseudo-drag-free system simulation for bepicolombo radio science using accelerometer data

The Mercury Orbiter Radio Science Experiment onboard the European Space Agency/Japan AerospaceExploration Agency (JAXA) BepiColombo mission aims at determining the gravity field and the rotational state ofthe planet to provide insight into its internal structure and at performing tests of general relativity. The experimentwill rely on accurate radiometric data provided by the onboard Ka-band transponder and on measurements of thenonconservative perturbations acting on the spacecraft, provided by the Italian Spring Accelerometer. This paperpresents a software implementation of a pseudo-drag-free system which includes the accelerometer measurements inthe orbit determination process. Numerical simulations focus on the identification of a suitable calibration strategy tofulfill the experiment goals pertaining to geodesy and geophysics. The achievement of the expected scientific resultswill depend meaningfully on the quality of the accelerometer data. Perturbative analysis aided in the identificationof a calibration strategy for the accelerometer data processing that allows obtaining an unbiased solution andcompensating for accelerometer errors.