Offline Analysis of Independent Guarded Assertions in Automotive Integration Testing

Abstract

The size and complexity of software in automotive systems have increased steadily over the last decades. Modern vehicles typically contain numerous electrical control units (ECUs), and more and more features require real-time interaction between several dedicated ECUs (e.g., gearbox, brake and engine control units) in order to perform their tasks. Since system safety and reliability must not be adversely affected by this increase in complexity, proper quality assurance is a must. Such quality assurance is often performed by testing the system in different levels of integration throughout the development process. However, the growth of complexity of the system under test aslo affects the testing, making it laborious, difficult and costly. This paper presents a novel method for efficient offline analysis of traces, which has been especially tailored for integration testing of automotive systems. The method exploits the recently defined concept of independent guarded assertion in order to formally describe the events that are relevant for the analysis as well as the expected behavior in those events. The offline analysis is implemented using a standard commercial model checker and has shown good performance in the conducted experiments.

From Natural Language Requirements to Passive Test Cases Using Guarded Assertions

“…In automotive system testing, scenario-based testing is commonly used, where a scenario is typically a sequence of system events [19]. This typically results in hardcoded scripted test cases that are difficult to test for non-determinism [18] as well as for interactions among various configurations and signal combinations. The proposed independent guarded assertions [20] allow for parallel execution of test cases, with frequent evaluation of assertions that are not typically captured in requirements and thus allows for testing of functional interactions.…”

“…A more general in-depth review of passive testing methods can be found in [15]. In previous work on the SAGA approach, interviews with practitioners [16] have shown that passive testing using guarded assertions [14], [17], [18] seems to contribute to small tests, preferably one test per requirement, which should facilitate both alignment as well as traceability.…”