A Consistency Analysis Method for Traffic Sequence Charts

TL;DR

This paper introduces a method for detecting inconsistencies in scenario-based requirements for automated vehicles using Traffic Sequence Charts, leveraging satisfiability modulo theories for precise conflict detection.

Contribution

It presents a novel formal analysis approach combining Traffic Sequence Charts with SMT solving to identify conflicts accurately in automated vehicle scenarios.

Findings

Method effectively finds inconsistencies in case studies.

Approach ensures conflicts are not due to approximation errors.

Scalability demonstrated in practical evaluations.

Abstract

The trend in the development of highly automated vehicles goes towards scenario-based methods. Traffic Sequence Charts are a visual but yet formal language for describing scenario-based requirements on highly automated vehicles. This work presents an approach for finding inconsistencies (conflicts) in a set of scenario-based requirements formalized with Traffic Sequence Charts. The proposed method utilizes satisfiability modulo theories solving on two-sided approximations of possible vehicle behavior. This ensures that found inconsistencies are not caused by approximations, but also occur when applying exact methods. Applicability and scalability of the analysis technique is evaluated in a case study.