Integration Test Procedures for a Collision Avoidance Decision Support System Using STPA

Abstract

The transition from conventionally manned to autonomous ships is accompanied by the development of enhanced Decision Support Systems (DSS) for navigators. Such systems need to consider interactions among hardware, software, and humans and their potential effects on system performance, which require rigorous testing to verify the system's safe decision-making ability and operational limits. Testing requirements for verification are aimed at 1) assessing the system's reliability and failure handling performance, and 2) integration testing. This work uses the System-Theoretic Process Analysis (STPA) to develop integration tests for a novel DSS. STPA is a structured methodology to identify hazards from multiple sources, including hardware or software failures, system interactions, and human errors. The objectives of the study are to develop and assess the feasibility of integration test procedures based on STPA. The stability monitoring subsystem from the DSS is analyzed as a case study. The results are used to suggest functional and performance integration test procedures.