Current on-board orbit determination concepts are in the most cases an integral part of the satellite avionics. However, it is believed that a capability of on-board precise orbit determination would allow to develop new areas of applications. E.g. autonomous station keeping (LEO, MEO and GEO), on-board SAR processing (LEO), missions with high resolution image processing (LEO) or missions related to atmospheric sounding.For this reason, this study shall investigate the conceptual approach for an on-board precise orbit determination system which is not a part of the on-board avionics.

The definition of the On-board Software Reference Architecture (OSRA) has led to the definition of a main model (the architecture itself, defined in OSRA), supported by other models focusing on specific aspects such as real-time, transaction, bus exchange, etc. or making the link with system such as the Spacecraft Data Base. The space system primes and space software providers have been starting to use various modelling languages (UML or DSLs) and various tools to support their in-house tailored software engineering processes.

The study is supposed to provide a wide-spread analysis not only limited to POD concepts, but also investigating the impact of the SSV extension on operational concepts for space users, GNSS software design, and ground operations.

The ISS Exploration Capabilities Study (IECS) is a joint study undertaken by ESA in cooperation with the 4 other ISS partners: NASA, JAXA, Rosscosmos, and CSA. In the IECS study, the human exploration programme for the period 2021-2030 is addressed. In this study it is proposed that in the first half of the 2020(s), a joint programme could start by building a Cis-Lunar Transport Habitat (CTH) vehicle. The CTH will be placed on a NRO orbit around the Moon. Safety of underlying trajectories is critical for rendezvous to human-tended infrastructure.

In an era of high resolution gravity field modelling the dominant error sources in spacecraft orbit determination are non-conservative spacecraft surface forces, such as: Solar Radiation Pressure, antenna thrust, Earth' albedo, thermal re-radiation, etc. The conventional approach to these problems is to use an empirical blind model which absorb all the forces but this approach introduces systematic errors and limit the prediction of the orbit. In the last years several wind-box model have appeared, developed based in GPS and Glonass official information, to overcome this limitation.