B4005 - Spacecraft Deep Space Navigation

Learning outcomes

The student learns in detail the techniques to perform the navigation of an artificial satellite outside the Earth orbit, from the cis-lunar to the deep space environment. The first part of the course focuses on the orbit determination process, used to estimate the past trajectory of a spacecraft from a set of measurements. In the second part, the main strategies to correct the deviations from the reference trajectory are explained. The theoretical framework is complemented by real-world examples and practical exercises using tracking data from past and ongoing deep space missions.

Course contents

Orbit determination:

- Introduction: concepts, ground and on-board systems, time and reference frames

- Dynamical model: the variational equations, the N-body problem, extended gravity, relativistic effects, non-gravitational perturbations.

- Observations: ranging, Doppler, DDOR, optical. Error sources and calibrations. Observation models, the light-time problem.

- Earth station location: frames, Earth orientation, tides.

- Estimation filters: linearized batch least squares, a priori information, constraints, consider parameters, stochastic parameters, solution evaluation.

- Radio science experiments: gravity, radio occultations, bistatic radar.

Guidance:

- Maneuver targeting methods

- The K-inverse matrix

Navigation analysis:

- Requirements definition

- Procedures and timeline definition

- Real mission examples (New Horizons, LICIACube, BepiColombo, Cassini, Juno, Europa Clipper, Rosetta, Hera)

Readings/Bibliography

Slides distributed by the teacher.

Further readings:

- James Miller, "Planetary spacecraft navigation", ISBN: 978-3-319-78915-6, Springer Cham (2018)

- Byron D. Tapley, Bob E. Schutz and George H. Born, "Statistical Orbit Determination", ISBN: 978-0-12-683630-1, Academic Press (2004)

- Theodore D. Moyer, "Formulation for Observed and Computed Values of Deep Space Network Data Types for Navigation", ISBN: 9780471445357, John Wiley & Sons (2003)

- David A. Vallado, “Fundamentals of Astrodynamics and Applications” (Fourth Edition), ISBN: 978-11881883180, Microcosm Press (2013)

- Richard H. Battin, “An introduction to the mathematics and methods of astrodynamics” ISBN 1-56347-342-9, AIAA education series (1999)

Teaching methods

During classes the subjects are presented by the lecturer, including the explicit proofs of all mathematical formulas introduced and to the presentation of the methods to solve the problems given in the practicing hours.

Some subjects are explored through practical exercises using Python.

As concerns the teaching methods of this course unit, all students must attend Module 1, 2 on Health and Safety online.

Assessment methods

The examination usually consists of three questions which allow to assess the capability of the student to resolve new problems or at least to set up the correct resolutive strategy. The assessment of such ability has a fundamental weight in the attribution of the final marks. The student must pass in at least two of the three questions placed by the lecturer in order to pass the examination.

Teaching tools

LCD projector, overhead projector and PC are used in addition to the standard blackboard.

Office hours

See the website of Marco Zannoni