Section: Application Domains

Supporting requirements engineering for aeronautic systems design

The design of embedded systems onboard certified civil aircrafts, for instance navigation, fly-by-wire and FADEC (Full Authority Digital Engine Control) applications, has to follow a stringent discipline imposed by civil aviation authorities. Designers have to provide evidence that both the design process they used and the system under design meet several industry standards, including the well-known ED-79/ARP-4754A and the DO-178 A/B regarding hardware and software artifacts.

These standards prescribe that every feature of a design can be traced back to one or several system-level requirements. Conversely, evidence shall be provided that every requirement has been accounted for. Correctness, consistency, compatibility and completeness of requirements are four key properties described in the ED-79/ARP-4754A standard that should also be assessed every time requirements are transformed. This puts a high burden on designers, especially on the system architect: requirements capture and analysis is by large a heuristic and manual process.

Formal requirements engineering is in its infancy: mathematical models, formal analysis techniques and links to system implementation must be developed. We advocate the use of contract-based reasoning techniques (see section  3.3 ) to support requirements engineering activities, during the early stages of the design process [4] .