An auto-review tool for model-based testing of safety-critical systems

Verification of Test Procedures and Test Cases (TP, TC) is an important process stage for fulfilling the RTCA/DO-178B/C compliance objective while developing software for safety critical flight control systems. Correctness of these results, their requirement coverage (High/Low level) analysis and justified discrepancies (if any) are the primary objectives that must be satisfied. Manual reviews are the most common methods for achieving these objectives. This paper consolidates some of the past experiences of conducting manual reviews in the flight control software V&V for a commercial aircraft program. Through them a clear need and scope for automating portions of manual review is identified. This led to the development of an Auto Review Tool (ART) which is qualified for claiming the certification credits. All the necessary documents such as Tool’s Operational Requirement (TOR), Tool Qualification Plan (TQP) and Tool Assessment Summary (TAS) are prepared. The paper presents the tool development process beginning with defining a library of Input/Output relation based functions for different control blocks, parser development and qualification activity that were performed by an independent testing team.