What are the primary outputs of SAVOIR?

• Reference avionics architecture for spacecraft platform hardware and software
• A set of standard avionics external and internal interface specifications
• The definition of building blocks composing the architecture
• The functional specification of selected building blocks comprising the architecture
• Process definition and assessment

One avionics reference architecture

The first result of SAVOIR is a commonly agreed view on the notion, scope, extent and elements of a single avionics architecture:

A single functional reference architecture

The global avionics view is translated into a functional view of the reference architecture. There is no constraints on the physical implementation of the functions into hardware and software components.

A set of hardware generic specification and interface

The functions are grouped and elaborated into a set of generic functional requirements. The grouping has been done according to current practices, but does not constraints the physical implementation:

• generic On-Board Computer (OBC) specification
• generic Remote Terminal unit (RTU), or Data Concentrator, specification

Some selected interface are described:

• interface between platform and payload
• interface between, on one hand the computer and its software, on the other hand the sensor and actuators of the control functional chain

The impact of an Integrated Modular Architecture approach and a Time and Space Partitioning concept on software and hardware architecture is specified.

A software reference architecture

The software architecture is streamlined in order to be less sensitive to the differences between projects. These so-called "variabilities" are localized into the architecture to minimize their effects.

The overall architecture, split between an application software and an execution platform, is based on a Space Component Model specified by a meta-model and a textual semantic. Services offered by the execution platform are described. Some of them rely on the CCSDS SOIS standards.

The importance of spacecraft operation

Spacecraft operation has a significant relationship to on-board avionics. The way the spacecraft is operated (the operability concept) impacts architecture and software.
Interface between ground and board, as well as impact on ECSS related standards, are described.