FRETting About Requirements: Formalised Requirements for an Aircraft Engine Controller

Farrell, Marie; Luckcuck, Matt; Sheridan, Oisín; Monahan, Rosemary

doi:10.1007/978-3-030-98464-9_9

Cited by 19 publications

(6 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In previous work, we derived fretish requirements for an aerospace engine controller, from naturallanguage requirements and test cases supplied by our industrial partner [7,15]. We used our adapted Extract Requirement refactoring to extract duplicated definitions of concepts that were repeated in the natural-language requirements, which we call fragments, into their own requirement.…”

Section: Discussionmentioning

confidence: 99%

“…Our fretish requirements set is derived from the 14 English-language requirements and 20 abstract test cases provided by our industrial partner, see [7]. We reuse the natural-language requirements' naming convention in the fretish set.…”

Section: Refactoring Fretish: Applicationmentioning

confidence: 99%

“…Requirements in the Wild: Our requirements set was developed in collaboration with our industrial partner [7]. To the best of our knowledge, this is the first set of fretish requirements that have been constructed alongside an industrial partner for a system that is still under development [8].…”

Section: Technical View Of Extending Fretmentioning

confidence: 99%

“…Our industrial partner supplied 14 abstract requirements, which we mapped one-to-one into fretish. Elicitation discussions with our industrial partner produced 42 fretish requirements in total [7].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Why just FRET when you can Refactor? Retuning FRETISH Requirements

Luckcuck¹,

Farrell²,

Sheridan³

2022

Preprint

Self Cite

View full text Add to dashboard Cite

Formal verification of a software system relies on formalising the requirements to which it should adhere, which can be challenging. While formalising requirements from natural-language, we have dependencies that lead to duplication of information across many requirements, meaning that a change to one requirement causes updates in several places. We propose to adapt code refactorings for NASA's Formal Requirements Elicitation Tool (FRET), our tool-of-choice. Refactoring is the process of reorganising software to improve its internal structure without altering its external behaviour; it can also be applied to requirements, to make them more manageable by reducing repetition. FRET automatically translates requirements (written in its input language fretish) into Temporal Logic, which enables us to formally verify that refactoring has preserved the requirements' underlying meaning. In this paper, we present four refactorings for fretish requirements and explain their utility. We describe the application of one of these refactorings to the requirements of a civilian aircraft engine software controller, to decouple the dependencies from the duplication, and analyse how this changes the number of requirements and the number of repetitions. We evaluate our approach using Spot, a tool for checking equivalence of Temporal Logic specifications.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Refactoring Fretish: Applicationmentioning

confidence: 99%

Section: Technical View Of Extending Fretmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Why just FRET when you can Refactor? Retuning FRETISH Requirements

Luckcuck¹,

Farrell²,

Sheridan³

2022

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…requirements that can be processed by formal analysis tools [10,17,42,45]. Additionally, FRET has been used by external (to NASA) industrial and research teams, e.g., for the formalization of aircraft engine controller requirements [19]. FRET's realizability framework has two main goals: 1) to implement efficient algorithms for checking realizability, and 2) to provide user support in understanding and correcting sources of unrealizability.…”

Section: Introductionmentioning

confidence: 99%

Capture, Analyze, Diagnose: Realizability Checking Of Requirements in FRET

Katis

Mavridou

Giannakopoulou

et al. 2022

Computer Aided Verification

View full text Add to dashboard Cite

Requirements formalization has become increasingly popular in industrial settings as an effort to disambiguate designs and optimize development time and costs for critical system components. Formal requirements elicitation also enables the employment of analysis tools to prove important properties, such as consistency and realizability. In this paper, we present the realizability analysis framework that we developed as part of the Formal Requirements Elicitation Tool (FRET). Our framework prioritizes usability, and employs state-of-the-art analysis algorithms that support infinite theories. We demonstrate the workflow for realizability checking, showcase the diagnosis process that supports visualization of conflicts between requirements and simulation of counterexamples, and discuss results from industrial-level case studies.

show abstract